ARQ
Bioactive Ceramics Bio-Integrative Design Studio
Architecture and Urban Strategies 7th Semester - 2019
Academic director: PhD. David Durán
Academic coordinator: MArch. Yessica Mendez
Leading Professor: MArch. Yessica Mendez
External Advisor: PhD. Guadalupe Rojas Verde
Students: Karen Kay Garza, Grecia Cortes, Frania Logan, Jesús Villalobos, Iván Durán, Lina Mejía, Carlos Muñoz Jose Luis Patiño, Regina Zermeño.
With the support of: Jose Ines Moreno, Noe Calderon, Lucas Hernandez, Alfredo Rodriguez, Gerardo Villagomez, Karla Hernandez, Cesar Velazquez, Ramon Marquez, Julio Zárate, Armando Castro, Isela Mendoza, Daniela Apresa, Itzeel Ramirez, Daniela Treviño, Isaac Garza, Victor Rios, Dorian Garcia, Isidoro Galavis.
Sponsor CATO | Cerámica
Bioactive Ceramics
Abstract
To encounter the current environmental problems, different bioremediation techniques have been applied, among which the use of beneficial microbial agents and their products have gained popularity, as well as the combination with digital technologies and the design of specific geometries to potentiate optimal conditions. For these agents, an ideal environment is generated to obtain the purification and synthesis of air pollutants. Based on the use of natural elements such as microorganisms and ceramics as a support medium, together they provide a harmonious aesthetic in balance with contemporary architecture and nature. The biofilter was designed based on the Bernoulli wind tunnel principle, where the shape of the piece directs the polluted air to the center of the piece through the tunnel where the bacteria capable of degrading volatile organic compounds (VOCs) is placed, specifically, the BTEX produced by the burning of hydrocarbons, industry emissions, and products commonly used as sprays and solvents. The purpose of this project is the development of an open biofilter applied in an architectural system using ceramics as a support medium for bacteria capable of degrading air pollutants.
1. 1.1 1.2 1.3 1.4
Introduction Architecture, Design and Biotechnology Timeline Aim State of art
9 10-11 12-13 14-15 16-19
2. 2.1 2.2 2.3 2.4
Research Biofiltration Pollution Microorganisms in biofiltration Ceramics as bed medium material
21 22-23 24-25 26 27
3. 3.1 3.2 3.3 3.4
Materials and methods Bacterial culture Material characterization Bacteria in ceramics Open biofiltration system efficency
29 30-35 36-43 44-51 52-53
4. 4.1 4.2 4.3 4.4 4.5 4.6
Geometrical exploration Study of environmental factors Form finding Voronoi diagram Reaction-Difussion Folds Bernoulli wind tunnel
55 56-59 60 60-61 61-62 62 62-73
Index
5. 5.1 5.2 5.3 5.4
Prototyping Slip casting Prototype 1 Prototype 2 Prototype 3
75 76 76 77 77-81
6. 6.1 6.2 6.3
Design proposal Design proposal morphology Environmental simulations Final representation
83 84-86 87-90 91-93
7. 7.1 7.2 7.3 7.4 7.5
Production Fabrication Process Milling strategy Gypsum mould fabrication Mixture casting and drying process Glaze application
95 96 96 97 97-98 98-99
8. Installation 8.1 Exploded isometry 8.2 Installation area
101 102 103-105
1.
INTRODUCTION
Biodesign: Architecture & Biotechnology
Bioactive Ceramics
Image 1.1a Cottonopolis (1840), showing the mass of factory chimneys due to industrial revolution in Manchester, England.
Image 1.1b Fallingwater house (1935) designed by Frank Lloyd Wright inspired by the architect’s desire to integrate human-made structures into the natural world.
1.1 Architecture, Design and Biotechnology There is always been a discussion of architecture and its symbiosis with nature as long as the history of architecture, starting with the use of nature as protection, to its use in construction materials, going through stages of biomimicry and inspiration in gardens and facades, on building exteriors, in a goal of trying to unite architecture with nature in an aesthetic and functional way. To talk a little about the relationship of nature with architecture, we can begin to highlight the link that has been between them for years, the first cities were made with stone and rammed earth, with dry vegetation as well as earth binders, passing through the speech in which Vitruvius in Da Architectura book mentions the distribution of the buildings according to the inclination of the stars, according to the location of the meridians as well as the air currents coming from the poles and the equator and in the which emphasizes the best location for optimal building conditions. [1.1a] Over the years nature and design always were part of each other due to the primary material that was obtained from the earth to use in design, but this relationship was broken in the development of industrial revolution (Image 1.1a) in which nature was seen as primitive and dangerous and where business and mass production
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took place in industries which started to contaminate the city but also its surroundings, transforming the cities into the primitive and dangerous places they call nature before, all this situation started to influence in architects and designers which started to bring back elements from nature as we see on the Art Nouveau movement (1,800) who used nature forms and inspirations in their designs, until having a complete integration as architect Frank Lloyd Wright in his project falling water house (Image 1.1b) bring the city to nature and involved both to work together as a one using starting an organicist tendency. On the biotechnology side, microorganism were been used since the first documented beer fermentation in which ancient Chinese people obtain beer fermented through yeast and grains, been also involved in cheese production and where certain cheeses are named after its particular species of microorganisms been designed the time and humidity and temperature this particularly food need to obtain the final good result. A big event that changed the Middle East and their relation with Asia, was the silk obtained from the silkworm which in form of biomimicry made fabric out of this material having domesticated the technique and the worms farm. Other applications of design in biology involving bacteria
Introduction
Image 1.1c Biocement (1974), the first bio-cement for industrial applications was invented.
identification with morphology and staining colors through the design of the cloning of the first mammal obtaining positive results and which change biotechnology as we know it now. Being this two areas largely separated but at the same time and in a certain way very closed between each other with the development of new technologies, we have the integration of design and biology on different projects, being one of the first reported the creation of a biocement (1974) which is produced by a stone catalytic bacteria, which can decompose some stone mineral into biocement and which has huge industrial application (Image 1.1c). We can say this moment started a new path on the creation of “BioDesign” with integration of this two studies having a exponential growing in the XXI century starting with the artist steve pike in 2001-2003 which created one of the first architectural installation for air microorganisms to growth within the structure and created an art piece with them, being followed by several project until an systematic design as the Microbial Home by Phillips in 2011, The Algae Powered House with the energy produced by the photosynthesis of the algae in the windows building, going through the development of Mycelium Biobricks installed on the MOMA [1.1b] as well facades elements for air decontamination with several micro-
organisms, being applied also on differential materials and shapes geometries which influence on the environmental conditions and hosting the optimum conditions for the microorganisms, having an integrative design and system where we can find this previously lost equilibrium with nature. (Figure 1.2) The introduction of nature in architecture must be part of a project since the beginning, integrating as part of the initial construction as one, but given the complexity of natural forms, as is mention in the book The beauty of ecology architecture of Josep Montaner [1.1c] the use of patterns for the generation of forms that have greater ecological capabilities, composed of both architectural spaces and ecological materials. In this combined ecosystem we can find an approach for solutions to some the actual problems that affect today’s civilization. Therefore the objective of this project is to use architectural geometric elements influenced by environmental conditions for hosting the optimum condition for bacteria and help on the contaminated urban cities. “Working like an ecosystem and sharing lessons from nature is crucial in today’s challenging times”. - Geanne van Arkel, Head of Sustainable Development Interface.
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CHEESE, MICROBES GIVE THEIR FLAVORS
FERMENTATION WITH YEAST IN BEER MAKING
TECHNIQUE FOR STAINING BACTERIA
SILK, 1ST BIOMIMICRY AND FABRICS MADE
VITRUVIUS DE ARCHITECTURA
BACTERIA THAT PRODUCE BIOCEMENT
ART NOUVEAU MIMIC NATURAL FORMS
FRANK LLOYD INTEGRATES THE CITY INTO THE COUNTRYSIDE
MOST ANCIENT
INDUSTRIAL REVOLUTION DETACHMENT WITH NATURE
1.2 Biodesign Timeline
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1ST MYOELECTRIC ARM IS DEVELOPED
BIO-DESIGN
ARCHITECTURE & DESIGN
BIOTECHNOLOGY
Bioactive Ceramics
CONTAMINA BY STEVE P
CONTAMINANT BY STEVE PIKE
THE ALGAE HOUSE BY SPLITTERWERK
TOWER OF GROWN
INDUS BY
BIO-DESIGN
BACTERIA THAT DUCE BIOCEMENT
Introduction
MICROBIAL HOME BY PHILIPS
ALGAE CELLUNOI BY MARCOS CRUZ
BIORECEPTIVE CONCRETE FACADE BY MARCOS CRUZ
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Bioactive Ceramics
The development of an open biofilter applied in an architectural system using ceramics-
-as a bed medi of degrading po
CERAMICS
Physics characteristics
ARCHITECTURE
Bacteria able to degrade VOC
Biofiltration
Porosity
Capilarity
pH and composition
Control of environmental conditions Temperature
GEOMETRY
Rain water Windflow
Figure 1.3. Aim and flow chart of the project.
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VOC
BTEX
Introduction
filter applied in sing ceramics-
-as a bed medium for bacteria capable of degrading pollutants from the air. BACTERIA
hysics acteristics
Bacteria able to degrade VOCs
Biofiltration
larity
onmental ns
BIOTECHNOLOGY
Temperature
Rain water
dflow
VOCs
BTEX
POLLUTION
1.3 AIM Our aim in this project is to create an architectural system using ceramics as a bed medium for bacteria that degrades contaminants from the air. The project was divided into two areas of study: architecture & biotechnology. (Figure 1.3) In the area of architecture, we can find ceramics and geometry, in which ceramics plays a roll on the properties of the material as the optimal pH for hosting the bacteria, as well some physical characteristics like the size of the porosity, having a characterization of the material to use and the optimal conditions to host the bacteria. In the design geometry, we can find a way to control environmental conditions to host bacteria being the wind flow, temperature, and humidity, the most important conditions to take into account for
the most suitable conditions for the bacteria. Talking about biotechnology, in this area, we cand find the pollutants, like the VOCs (Volatile Organic Compounds) the contaminants more abundant in the air, also referring to the bacterias capable to degrade contaminants and suitable for laboratory manipulation. In the involvement of bacteria and pollutants, we can find their use in a biological treatment method called biofiltration, a very common system in the industrial sector for purification of air and water. The final purpose of this project is to use a biofiltration open method using bacteria as a degradation pathway for VOCs in the city urban air, because of its high concentration causing an increase in respiratory and heart diseases on the population. [2.1a]
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Bioactive Ceramics
1.4 State of art 1.4.1 Contaminant by Steve Pike This project is the result of a series of investigations that, together with other projects, culminated in an architectural installation. Rather than considering the ability of micro-organisms to modify their immediate environment as his previos work Nonsterile to investigate and monitor the capabilities of a designed installation and develop with the purpose of adhering and developing microorganisms that are present in the London subway environment and reveal the resulting morphological aesthetic. (Image 1.4.1) Initially, a series of portable monitor vessels were created and exposed to particular locations and their attendant microbes in order to discover the common micro-organisms present and to identify those specific to a given environment. Aspergillus, commonly present in the fabric of our built environment, and Micrococcus that populates the surface of our skin, proliferated across all the monitor cells. But other more distinct microbes, directly associated with plant, fruit, bread or dairy material present at the particular site of exposure, gave rise to unique visual transformations in turn revealing an almost epidemiological history. The investigation progressed to the proposition of an architectural intervention; a designed object embracing the
image 1.4.1 Contaminant (2003) an architectural installation designed to apprehend locally present microbes and to reveal the resultant morphological aesthetic.
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disciplines of microbiology and mycology, alongside architecture and engineering. The structure, incorporating responsive monitor vessels and the support systems required to sustain them, is hypothetically located where arbitrary micro-organic material would be incidentally introduced. The subterranean vascular network of the London Underground provides airborne highways for particulate matter across the city. London’s inhabitants act as unwitting hosts to microbial populations, introducing catalytic material describing individual daily activity. A series of monitor vessels and occupational clusters are proposed to colonise a redundant portion of Holborn Station, capturing and propagating the ambient particles. To construct this proposed condition, a 1:10 scaled installation was created; nevertheless incorporating authentic monitor vessels and their associated support systems, facilitating the chemical, humidity and temperature controls necessary. This resulted in an architecture of contamination where the fabric and spatial possibilities of the installation reconfigured with every microbial progression. A multitude of processes were utilised to create the monitor vessels, including CNC milling and laser cutting, vaccum forming, various laboratory equipment and incubators. [1.4a]
Introduction
image 1.4.2 The Algae House (2012), the world’s first building to be powered entirely by algae by engineering firm Arup, in Hamburg, Germany.
1.4.2 The Algae House by SPLITTERWERK The project is a collaboration between Spitterwerk Architects, Strategic Science Consult of Germany, ARUP and Colt International. IBA in Hamburg set itself a goal: to shape the future of cities in the 21st century. As a part of this ambition, it developed several projects that provided innovative and sustainable responses to today’s questions about urban development. Is a cubic, five-storey passive-energy building named “The algae house”. (Image 1.4.2) A previous project that used microorganisms was The algae house by SPLITTERWERK, Label for Fine Arts and Engineering in 2012. This building was the first using an algae bioreactor facade in the world. They placed the algae 130 translucent glass photo bioreactors to capture energy and generate electricity and heat inside the building. The algae does photosynthesis, by absorbing light from the sun and CO2, making the facade reduce the CO2 of the environment. In the panel itself of 2.5 x 0.7 meter, microalgae are cultivated in a watery culture medium that then perform photosynthesis by absorbing natural light. Subsequently, once the algae have done enough growing, it is harvested and fermented to create biogas, which is used to heat the building.
They are able to store carbon dioxide and produce biogas in the in-house fuel cell which generates 4,500 kWh per year. Additionally produces around 32 MW heat per year that can either be directly used in the house or fed into the local power network, or alternatively, temporarily stored underground. The facade fulfils all functions expected of a conventional building cladding: it not only acts as a thermal and sound insulation, but also as a sun shield. In addition to providing renewable energy, the translucent panels can act as a shading system for the house’s windows, and provide a reasonable increase in acoustic insulation. “Using bio-chemical processes in the façade of a building to create shade and energy is a really innovative concept. It might well become a sustainable solution for energy production in urban areas, so it is great to see it being tested in a real-life scenario”, said Jan Wurm, Arup Research Leader. Algae coating is the perfect example of the main problem that affects renewable energy: it is an effective, efficient and sustainable technology. [1.4b]
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Bioactive Ceramics
image 1.4.3. Indus (2019) a modular system of ceramic tiles inlaid with algae that can filter toxic chemical dyes and heavy metals out of water.
1.4.3. INDUS by Bio-ID Barlett The Bio-Integrated Design Lab at the Bartlett School has created a modular system of tiles inlaid with algae that can filter toxic chemical dyes and heavy metals out of water. Led by Dr. Brenda Parker, Prof. Marcos Cruz and Shneel Malik, created ‘Indus’, a tile-based, modular bioreactor wall system, based on the principle of bioremediation. The structure is designed to really hold algae-laden hydrogel for cleaning really heavy materials from wastewater. Inspired by the architecture of a leaf, water flows over a series of vein-like channels containing algae prepared in a seaweed-based hydrogel in a pretty big way. Pollutants basically such as cadmium are sequestered by the algae and the hydrogel can then be processed to really recover sort of heavy metals safely, which actually is quite significant. the project meets the need for a simple, scalable and a sustainable system that can treat heavy metal contaminated wastewater on a local level. (Image 1.4.3 & 1.4.4). Indus is designed to be built on site in areas with contaminated water sources, where artisans can pour water over the tiles to kind of purify it. Each tile is made simply by pressing clay or a similar low-cost, actually local material, into fan-shaped moulds with a series of vein-like channels. The shape of the tile mimics the structure of the leaves and their ability to distribute water evenly
18
to each part of a plant. The chanels are filled with microalgae that remain within the “biological scaffold” of an algae-derived hydrogel. This keeps algae alive and at the same time is completely recyclable and biodegradable. Once filled with the hydrogel, the tiles are assembled into a wall and water is poured into the system through inlets at the top. It drips through the mosaic channels and is collected at the bottom. As it flows through the channels, water is subjected to a bioremediation process in which microorganisms, in this case algae, are used to consume and decompose pollutants in the environment. “Algae produce a set of compounds called phytkelatins, which allow to capture these metals, without which they could not grow”. The compounds remove contaminants from water and deposit them inside the algae cell, where they are stored. For this reason, the hydrogel must be replaced with new algae when it becomes saturated and the bases can be reused continuously. Each modular unit is attached to the next one through half-turn joints, so it can be removed individually without disassembling the entire system. This is important, since it allows easy maintenance and adaptation to the limitations of the environment. The particular size of the tile wall can be customized to fit the available space. [1.4c]
Introduction
image 1.4.4 Each modular tile unit is attached to the next through half-lap joints, and so can be individually removed without taking apart the entire system.
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2.
Research Biofiltration system
Bioactive Ceramics
4 Water and Nutrients
Treated air
Humidified gas
2
3
Filter bed Humidifier
1
Pump
Contaminated air
Water
Figure 2.1a. Conventional biotrickling filter system.
22
Humidifier
Water purge
Research
2 Humidity (Liquid)
1
Cleaned air
2 CO2 + H2O
3 POLLUTANS
HUMIDITY
3
4
MICROORGANISM
MEDIUM MATERIAL
Microorganism (Biofilm)
1 VOCs BTEX (Gas)
O2
Medium Material
4 Figure 2.1b. Open biofilter system and its characteristics.
2. Research 2.1 Biofiltration method Biofiltration is a method of biological treatment that helps to integrate natural processes in immobilized aerobic microorganisms for decomposing volatile air pollutants. Microorganisms on biofilters can oxidize various pollutants and use them as their sole carbon and energy source. [2.1a] A biofilter is a bioreactor fed with packing media where the microorganisms grow in suspension or attached, having an open or closed system with a passive or active filtration. [2.1b] (Figure 2.1a) The efficiency of biofiltration highly depends on the cultures of microorganisms proliferating in the biofilter bed medium, a biofilter inoculated with a pure culture can be better in removing pollutants, therefore, a proper selection of the biofilter bed medium and bacteria ensures the effective operation of a biofilter from the environmental point of view, as well as providing its economic feasibility. Microbial growth and metabolism depend on suitable environmental conditions, so, the biofilter performance is also related to the nature of the inlet waste gases, the type of packing material, bed temperature, moisture content, and pH. [2.1c]
Figure 2.1b describes the removal processes of pollutants in a biofilter consisting of three phases: gas, water, and biofilm. A pollutant is transferred from the gas phase to the liquid phase and then to the biofilm phase containing the microorganisms. Once the substrates are made bioavailable to microorganisms, the target pollutants are utilized as carbon sources for microbial growth and maintaining biological activity, and the compounds are simultaneously completely or partially mineralized. [2.1d] Biofiltration is one of the most practical technologies for eliminating volatile pollutants from the air environment. It can be used in architectural applications, as well as taking place in common life activities. In recent years, new types of biofilters and new packing materials have been created for air pollution control, they offer a sustainable and eco-friendly solution for air pollution control, with low maintenance costs. For instance, implementation at industrial scale increased in recent decades. Hence, we want to design an open biofilter applied to architectural elements due to the increase of air pollutants in urban areas.
23
Figure 2.2a Anual mean concentration of VOCs around the world.
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HEART DESEASE
KIDNEY DAMAGE
LUNG CANCER AND RESPIRATORY DESEASES
HEADACHE, STROKE
SAN SALVADOR, EL SALVADOR
MONTERREY, MÉXICO
COYHAIQUE CHILE
AIR QUALITY KILLS 5.5 MILLION WORLDWIDE ANNUALLY
BAMENDA, CAMEROON
LONDON, UK
ZABOL, IRAN
GWALIOR, INDIA
XINFTAI, CHINA
Bioactive Ceramics
Research
Petroleum and natural gas extraction
Petrochemical activities
Transport sector exhausts
Solvents and sprays
BENZENE
TOLUENE
ETHYLBENZENE
O-XYLENE
CH3
CH3
CH3
CH3
When mixed with nitrogen oxide, they react to form ground level ozone or industrial mist (smog), which contributes to climate change.
Figure 2.2b Chemical composition of the BTEX and their main pollutant emitters.
2.2 Pollution Air pollution is a world-class problem, in just a decade the levels of pollution in the environment have increased so much that it is the cause of more than 3.8 million deaths around the world every year. (Figure 2.2a) At this time, different solutions have been developed to attack this problem, such as the integration of vegetation on facades, green areas in public spaces and interior gardens, but it has been proven that these techniques are not efficient enough and are usually expensive and constant maintenance. Many studies have shown that volatile organic compounds (VOCs) are among the major air pollutants, and impact human health substantially. [2.1d] A VOC is any carbon compound (except CO, CO2, carbonic acid, metal carbonates and ammonium carbonate) with sufficient capacity to participate in atmospheric photochemical reactions, that is, with sufficient photochemical reactivity to participate in the formation of ozone or secondary aerosols. [2.1c]
VOCs such as benzene, xylene, and toluene (BTEX) are among the main air pollutants emitted in large quantities from industries producing paper, wood products, as well as fuel/petroleum industries, pharmaceutical operations and common life products such as intermediate chemicals, such as solvents for greases, inks, oils, paints, plastics, fuels for internal combustion engines, etc., threaten the environment and human health. (Figure 2.2b) They cause offensive odors, are toxic and harmful to human health. Therefore, cost-effective and environmental-friendly technologies are needed to control volatile pollutants. [2.1d] Biological techniques as biofiltration, based on microbial metabolism are usually more effective than other techniques for controlling VOC emissions. Effective co-elimination of multiple VOCs in air biofiltration systems is based on the presence of active microorganisms and biofilms. [2.1c] Therefore, our crucial interest in investigating these microorganisms capable of degrading VOCs, mainly BTEX, is important.
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Bioactive Ceramics
PATHOGEN
HANDLE
HABITAT
SYNERGISM
METABOLISM
NUTRIENTS
TEMPERATURE
DEGRADES
NON PATHOGENIC
EASY
SOIL
SYMBIOSIS
AEROBIC
SAPROTROPHIC
MESOPHILIC
VOCS
100%
Bacillus subtilis
Microoganisms used in biofiltration of air
75%
Pseudomonas putida
50%
Bacillus sphaericus
25%
Pseudomonas tzutserii
0%
25%
50%
75%
100% PATHOGENIC
DIFFICULT
WATER
SOLITAIRE
ANAEROBIC
CHEMOTROPHIC
THERMOPHILIC
OTHER
Figure 2.3 Selection of the most suitable bacteria.
2.3 Microorganisms in biofiltration In general, biofiltration activity is mainly due to bacteria that exhibit a high diversity and versatility when treating VOC mixtures. Extensive fungal biomass growth may lead to packing media clogging which has been reported to be the most important drawback in fungal biofiltration, [2.3a] the application of specific single species or mixed microorganisms may alter substrate interactions and consequently enhance removal performance.
ingested has beneficial effects, likely by helping to maintain or restore healthy bacterial communities in the body.
The number of microorganisms depends on the origin of the pollutant, the pH and temperature inside the biofilter and the moisture of the porous plates. Paecilomyces variotii, Rhodotorula mucilaginosa and Bacillus subtilis were the most common organisms found during filtration of all examined volatiles[2.3b], as well acetone can be degraded by naturally occurring soil bacteria P. aeruginosa, S. aureus, B. cereus, B. subtilis.
Therefore, mixed cultures exhibit greater diversity and versatility in simultaneously treating VOC mixtures in biofilters. Nevertheless, a large number of strains in a biofilter can offer various pathways for the degradation of different substrates, consequently increasing the stability of microbial population and contributing to a better response to changes in environmental conditions.
B. subtilis bacteria effectively degrade volatile organic compounds such as toluene, benzene, and xylene. B. subtilis dominated in the plate type biofilter during the whole experiment independent of the inlet pollutant. B. subtilis can be isolated, in greater numbers than most other spore-forming bacteria, from the rhizosphere of a variety of plants, B. subtilis has been touted as a probiotic that when
26
We focus on B. subtilis but inevitably other microorganisms grow together, whereas, its found that a mixed media works well. A wide distribution of various groups of microorganisms in the biofilter allows a more effective elimination of pollutants from the air. [2.3c]
B. subtilis can be accompanied by S. putida or S. aeruginosa to have better efficiency. However, compared to the biodegradation of single substrates, the microbial composition, microbial interactions, and abundance of microorganisms may be altered by introducing other substrates into the biofilter, as well as, the acclimation process and the chosen bed medium. Therefrom, the selection of B. subtilis and a single specie is applied in this project. (Figure 2.3)
Research
Image 2.4 Ceramics uses as bed material medium.
2.4 Ceramics as bed medium material The main advantages of the use of immobilized cells in comparison with the suspended ones include retention of higher concentrations of microorganisms, protection of cells against toxic substances and prevention of suspended bacterial biomass in the effluent [2.3a]. Moreover, the immobilization of microbial cells provides, in general, high degradation efficiency and good operational stability. An appropriate biofilter media must have a large surface area for both adsorptions of contaminants and for supporting microbial growth. It should be mechanically resistant, adecuate porosity, as of retention of humidity. [2.1c] In the search for different bed mediums for biofiltration we found that ceramics is a synthetic material commonly used thanks for its porosity characteristics as well the suitable conditions for temperature and humidity for bacterial growth, also being a very versatile material for giving a selected geometry and its durability to environmental conditions. Ceramics is a good synthetic medium for a biofiltration system based on the following practical considerations: a relatively low
cost due to local availability and the ease of preparation, thermal and humidity properties, durability, and large industrial scale production. The interaction of cells with the ceramic support results in a remarkable increment of the metabolic rate of the resulting adsorbed cells, as reflected by the observed enhancement of their respiratory rate and lower lag periods. There are different forms in which ceramics bed mediums are made, they can be small balls as a well big block of ceramics, in which the microorganisms are placed for biofiltration. [2.1d] (Image 2.4) Having the posibility of designing a certain form geometry, with the optimal conditions for the bacteria in an open environment, as well, the application of different agregates like glazing, with the posibility of a mass production of the shaped molds and ceramics pieces. Giving the versatility of the ceramics and its geometrical form capacities, the mold creation and fast production, as well as, massive local fabrication, its common use in biofiltration; lead to the use of ceramics as bed medium material for this project.
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3.
Materials and Methods
Bacteria culture & Ceramics
Bioactive Ceramics
Image 3.1a Bacillus subtilis culture on Petri dish.
3.1 Bacteria culture 3.1.1 Characteristics of B. subtilis Bacillus subtilis is a very versatile bacteria, is one of the most common used as a role model on biotechnology due to its common presence in the environment as well its easy manipulation in the lab, high resistance to extreme environmental conditions, as well being a mesophilic bacteria which can live in an average temperature. B. subtilis is a gram positive, rod shaped bacterium, it is readily isolated from diverse natural environments such as soil, water and the rhizosphere of plants. Since, B. subtilis has become the primary model organism for all Gram positive bacteria. B. subtilis was traditionally regarded as an obligate aerobe but was later shown to be able to grow anaerobically by nitrate respiration and by fermentation. One of the most distinguishing properties of B. subtilis is its ability to form endospores, or simply ‘spores’. [2.3c] Spores are specialized survival capsules designed to protect the DNA of the bacterium under unfavorable conditions. In fact, spores have been described as the “hardiest known form of life on Earth”.
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In addition, B. subtilis spores can survive the gastrointestinal tract, and even appear to be able to germinate and re sporulate inside it. Following this, some have gone as far as to refer to B. subtilis as a “gut commensal”. B. subtilis is not confined to growth in liquid culture, but can also form complex multicellular communities on solid surfaces and at liquid air interfaces, called biofilms and pellicles, respectively. Which property is of great relevance, specially for the needs of our project. (Image 3.1a) Bacillus species are particularly suited for this purpose because they can easily grow under industrial production conditions, do not produce any toxic by-products, produce protein in high yields, and secrete the produced protein efficiently into the medium. The potential applications of B. subtilis discussed above, are but a few of many. It is interesting to note that many of the applications make use of one of the ways that B. subtilis deals with stresses, such as biofilm formation or sporulation, due to its high advantages in industrial processes. [3.1a]
Is not considered harmful to humans and animals.
NON-PATHOGENIC
Lives in the soil with other microorganisms and inside the body of humans and animals.
LIVES IN SYMBIOSIS
MESOPHILIC
This bacteria es aerobic but it can change to anaerobic
METABOLISM
It’s optimal growth temperature is between 15 and 35º C. But can survive in extreme conditions (55 - 70º C).
Can be found in a wide variety of terrestrial and aquatic environments, making it a widely adapted species to grow in different ecosystems.
FOUND IN SOIL
A defense mechanism when it’s in a hostile environment. These are highly resistant to the conditions of an external medium. When the environment is favorable again, the spores germinate and reproduce.
SPORE FORMING
It is very manageable. It is used for genetic manipulation and has been adopted as a model organism for laboratory studies. It has a natural fungicide activity, and is employed as a biological control agent.
VERSATILE
BTEX degradation.
VOCs DEGRADATION
Materials and Methods
Figure 3.1b Characteristics of Bacillus subtilis.
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Bioactive Ceramics
1. SAMPLE DILUTION
2. BACTERIA CULTURE
3. SPECIES DIFFERENTIATION
M1-1
4. STRAIN DIFFERENTIATION
5. PURIFICATION
TSI TEST
M1 M1-2
TSI RESULTS
SAMPLE 1 Collected from northeast side Decorative grass soil
M1-3
C2
C2m
M2-1
C3
C3m
M2-2
C4
C4m
C4r
M2-3
C1
C1m
C1r
M2
SAMPLE 2 Collected from southwest side Wild vegetation soil
Figure 3.1.2a B. subtilis Isolation process.
32
Materials and Methods
3.1.2 Isolation process of B. subtilis The bacteria was isolated from the ground soil, in order to be used on the proposed structure for air purification. In the process of bacteria isolation, two samples were collected from CEDIM’s ground soil. The M1 sample was collected from the northeast side from decorative grass and the M2 sample was collected from southwest side from wild vegetation. The sample was taken from the soil where B. subtilis is found, near the roots of the plants. Figure 3.1.2a represents the steps for bacteria isolation. The steps description are the following: 1. Sample preparation 5 grams of each sample were weighed and diluted in 25 ml of sterile water, then a thermal shock was placed for 10 minutes at 80°C for the elimination of non-desirable bacteria, to finally carry out 3 serial dilutions to each sample. 2. Plate culture The inoculation of the 3 dilutions into 3 Petri dishes were made from each sample. The Petri dishes filled with nutritive agar were then incubated for 72 hours at 30°C for bacteria to grow. 3. Differential selection of species. A colony morphology selection was made to discard other bacteria, then a second culture was made with the selected bacteria and nutritive agar. 4. Differential selection of strain. A second selection with Gram stain was performed, to discard Gram-negative bacteria and other bacillus species (Image 3.1.2b). For a differential selection of other bacilli, TSI test was made with two Petri cultures. One of the Petri dishes gave a positive result for acid production, meaning this bacteria is Bacillus subtilis. 5. Purification A fourth culture was made for selective bacteria purification. This culture was placed in refrigeration for future mass production and utilization in further projects.
Image 3.1.2b Bacillus subtilis gram stain micrograph. (Purple - Bacilli, Blue - Spore).
33
Bioactive Ceramics
3.1.2 Bacteria mass production 6. Mass production For the bacteria mass production, initially, we made 100 ml of nutrient broth (Image 3.2.1b), divided into two flasks 50 ml each, then inoculated with the last purification of B. subtilis (Image 3.2.1a), afterwards incubated 24 hrs at 30°C in agitation at 120 rpm. (Image 3.2.1c)
Image 3.1.2a B. subtilis culture.
Results were obtained (Image 3.2.1d), having a good growth on both flasks at 24 and 72 hrs. After 24 hours, UFC were counted resulting in 1x10^6 UFC/ml in each flask, which was able to be used for the sodium alginate gel. For the last inoculation, three 125 ml flasks with nutritive broth were used. The bacteria was incubated at 30 °C for 24 hours with agitation at 120 rpm (Images 3.2.1e, f, g, h).
7. Sodium alginate gel & vegetal colorant
Image 3.2.1b Two flasks of 50 ml of nutritive broth.
For the final pieces, 500 ml of medium in total was prepared, from which 50 ml were used in order to inoculate the bacteria and the rest of the 450 ml were used to prepare gel. [3.3] Firsth the sodium alginate was weight to get a 13% of proportion in a 1L of destiled water, (Image 3.2.2a) then it was diluted slowly and in agitation with the water until having no more grumes. Red and blue colorant was added 60 microliters, 30 of each one to get the wanted color. (Image 3.2.2b) Previously two diffeerent fel were made with a variation on the color source, being the vegetal colorant the chosen one due to its capacity of degradation by the bacteria and as a indicator of the bacteria process, also because the bacteria showed more growth with it. (Image 3.2.2c)
Image 3.2.1c Incubated 24 hrs at 30°C in agitation at 120 rpm.
For the project, a total of 56 pieces were made, each one inoculated with 5 ml of the preparation of gel and bacteria. The structure contains aproximately a total volume of 280 ml of media, but made a solution of 500 ml for have a reserved volume in case more is needed. (Image 3.2.2d) The inoculation was made through a tipless syringe upwards, wait for gel drying then, put the pieces back together on the column.
Image 3.2.1d Biomass growth.
34
Materials and Methods
Image 3.2.1e Weight of the nutrient broth.
Image 3.2.2a Weight of the sodium alginate.
Image 3.2.1f Preparation of the nutrient broth on flasks.
Image 3.2.2b Preparation of the gel and coloration.
Image 3.2.1g Inoculation of bacteria on nutritive broth flasks.
Image 3.2.2c Previous gel made to test their degradation.
image 3.2.1h Biofilm formation on biomass growth.
Image 3.2.2d Finished gel for inoculation of ceramic pieces,
35
Bioactive Ceramics
3.2 Material Characterization 3.2.1 Introduction Bacteria conditions Bacillus subtilis it’s a very versatile bacteria. It can reproduce itself on soil, clay or sand. It survives on humid environments surrounded by calcium, potassium, magnesium, phosphorus, sodium, alumina with an alkaline pH scale from 4 to 7, and can resist brutal changes such as temperatures from 4º to 30º C. When the environment is cold, sporulation of the bacteria occurs and when is under heat the growth process goes on. To compose a bio-receptive ceramic to shelter bacillus subtilis, the composition of the ceramic has to be modified in a specific path to make it the optimal medium. Ceramic already contains 8 of the elements that the bacteria need to be surrounded by to grow, now, the material needs more accurate conditions, so the bacteria get the opportunity to grow. As first, the pH scale needs to be adapted to a scale that can go from 4 to 7. Also, to maintain the humidity and give space to the bacteria to reproduce, the ceramic needs a range from 10% to 20% of absorption. The geometry of the ceramic modules was adapted to remain around environmental factors such as water rain, sunlight, and wind, provides also conditions for the material to be humid, to receive sunlight, generate shadows, develop wind flows and to provide space to the bacteria to realize their reproduction. The experimentation process of the ceramics that the project needs is based on exploring different variables of ceramic processes, analyzing physical and chemical properties such as plasticity, density, formation, absorption percentage, ph and also altering fabrication steps in order to achieve a ceramic that subserves also the biotechnological exploration that it is planned for the project.
Base Material Characterization Ceramic comes from the greek word keramikos, which means “burnt stuff”. It is an inorganic non-metallic solid formed with a mash of minerals and treated during a high-temperature process. It has a chemical composition made of aluminum, silica, iron, titanium, magnesium, calcium, potassium, and sodium that proceed from a mixture of different minerals and water.
36
The components of the ceramics come mostly from the ground, clay, kaolin, feldspat and silica (Image 3.2.1a & 3.2.1b). Each composite has its own physical and chemical properties that work together and make up the ceramic mixture. Since the raw material used on this project is provided by CATO, a white ceramic bathroom application manufacturer based in Santa Catarina, NL. the decision of taking the base ceramic mixture that the company produces every day by tons as the start point of our explorations was made. This mixture consists of 48% of clay which gives plasticity to the mix, and 8% of kaolin mixed up with water which in contact with these components generates body for the mixture. This mixture is then mixed with 44% of feldespat which adds flexibility and strength to the mix, and .2% of silica to give mechanical strength to the pieces. (Figure 3.2.1c). The water works just as a vehicle for the mixture to get done, because later at the setting the gypsum mold absorbs all the water of the mixture to get it dry. The liquid mixture needs to be in the optimal conditions for it to be correctly poured into the cast and to get the proper heating process without risks, conditions such as density, viscosity, formation, ph, and the temperature had to be measured to recognize the corresponding values of these conditions.
Properties measurements Some adjuments are made to the mixture before it is poured on the gypsum molds in order to get the correct viscosity, density, temperature, and formation for the ceramic mixture. The viscosity its measured with a viscometer by gravity which shows the time in which 500ml of the mixture is dropped into a container. The optimal times are between 28 and 30 seconds for that 500ml. The density is measured by its weight with an optimal scale of 1.80 to 182gm/cm3 tooked on a 182gm container. Temperature it’s measured with a laser that works like a thermometer. The optimal mixture needs to be around 30º and 33ºC. The formation is the weight that the mixture gets after been poured and waited 3 minutes to cut a 10cm. circumference and put under a weight check. This helps to visualize if the gypsum and the mixture will work correctly creating ceramic surfaces with an optimal thickness. All the mixtures used on this project were checked based on these conditions before any production process.
Materials and Methods
Image 3.2.1a Kaolin component.
image 3.2.1b Clay component.
37
38
Figure 3.2.1c CATO ceramic formula.
NA2O
K2O
CAO
MGO
TIO2
6.GLASSING Spray varnish 30 sec. drying
8 hrs 1160ยบ
CLAY
Plasticity
48%
7. HEATING
FE2O3
SIO2
FELDESPAT
44%
H2O
Flux & Strenght
5. SANDING
KAOLIN
8%
1. MIXTURE
20ยบ - 30ยบ 15hrs 80ยบ
4. DRY OUT
Mechanical Strenght
SILICE
.2%
1.2 MIXTURE
Clay slip catsting
3. MOULDING
Net 200 6% Resistance
2. SCREENING
Bioactive Ceramics
Materials and Methods
3.2.2 Ceramic Exploration The exploration of the mixture was started on small scales just to observe and get results of the most appropriate material for the contention of the bacillus subtillis. Small samples of 10cm diameter and 1cm of thickness of ceramic came as a result of this explorations. This small quantities let the pieces be properly analyzed and measured by its liquid properties such as density, viscosity, formation, ph, and also by it solid properties after being cooked such as absorption percentages, pH, finish, textures and color of our ceramic pieces. All mixtures where made with water and different components which will be mentioned on the next paragraphs, and mixed with a drill because of the scale of the samples. When the different mixtures are ready these ones are poured on small 11cm diameter clay molds reaching only 11mm. of thickness. From here theses pieces are now ready to get dry inside the over for about 5 hours so they can be cooked afterwards. Ceramic First Exploration (Figure 3.2.2a). To get to know the role and behavior of the components and different additives in the ceramics, it was needed to analyze them individually. This exploration was done based on the fact that the porosity of ceramics affects its flexural strength and may affect other properties such as density, hardness, corrosion resistance, and biocompatibility. The exploration consisted of mixing the base mixture with kaolin, silica, alumina and calcium carbonate in three different quantitative ranges to see how the properties of each mixture generate different characteristics over the cooked ceramic pieces, as, the absorption percentage. Twelve mixtures came from this experimentation divided into four groups of each component Test 1 The first group mixture test was with kaolin. Kaolin is used extensively in the ceramic industry, where its high fusion temperature and white burning characteristics make it particularly suitable for the manufacture of whiteware, porcelain, and refractories. Kaolin is generally used alone in the manufacture of refractories which present a porosity of 5% to 15%. When kaolin is mixed with water in the range of 20 to 35 percent, it becomes plastic (it can be molded under pressure), and the shape is retained after the pressure is removed. The test started adding 75gr. of kaolin to the1000gr. of the base mixture and it presented a .98% of absorption, then 100gr. was added to another 1000gr. of the base mixture and presented a 0% of absorption, the same percentage as the third mixture of this group which had 150gr. of kaolin on a solution of 1000gr. of base mixture. This means that the higher absorption percentage that the kaolin can give to the piece was with just 75gr. Test 2 The second group mixture test was adding silica to the 1000gr. base mixture. Silica is the name given to a group of minerals com-
posed of silicon and oxygen, the two most abundant elements in the earth’s crust. Silica is found commonly in the crystalline state and rarely in an amorphous state. Silica gives crystallinity to the ceramic as well as a mechanical strength when it is cooked. The test started adding 200gr. presenting a 1.26% of absorption. In the next mixture 300gr. was added and absorption of .53% came of it. The last mixture of this group was modified with 400gr. of silica and 1.79% of absorption was presented. In this test is visible that the porosity of the ceramic when 400gr. of silica are added to the mixture the porosity is higher than the first test with kaolin. Test 3 The third group mixture test was adding alumina to the 1000gr. base mixture. It is found naturally in corundum and emery, it is one of the main materials in the construction of clays and enamels. The major uses of specialty aluminum oxides are in refractories, ceramics, polishing and abrasive applications. It has a high thermal conductivity and a low coefficient of friction. The test started adding 200gr. to the base solution and presented a 1.12% of absorption. To the next mixture 300 gr. was added and a 2.11% of absorption came on the results. And the final mixture of this was with 400gr. of alumina in which the absorption was of 2.68%, the higher percentage yet in all the exploration. Test 4 The last group mixture test was adding calcium carbonate to the 1000gr. base mixture. Calcium carbonate is a calcium salt. It has a role as an antacid, a food coloring, a food firming agent and a fertilizer. It is the main source of calcium in glazes and also a flux in all types of glazes, it reduces crazing and increases hardness and durability and in large quantities produces a matt effect. The test started adding 100gr. to the base solution, the second test was with 200gr. and the third was with 300gr. of it. The measurement of the absorption test of this group is still not made. Conclusion The results of this exploration in terms of absorption percentages and finishes of the ceramic pieces gave us the information to conclude which elements are important for the purpose and to acknowledge details of the manufacturing process of the mixture. Now its know that kaolin gives roughness to the ceramic but it does not present a high porosity. Silica and alumina gave a higher percentage on the porosity scale and the calcium carbonate gave us the best appearance or finish on the ceramic and also a high porosity percentage. Also, the fact that the feldespat of the base mixture was vitrifying the ceramic because it is a flux material, so it was needed to reduce its percentage of the base mixture or replace it with calcium carbonate that is also a flux material but not as strong as feldespat.
39
Figure 3.2.2a Ceramic first exploration; Porosity test l.
pH Scale
Absorption %
Base
1000gr.
Test 4
Test 3
Finished Low fundant capacity
CALCIUM CARBONATE
Strenght Low Weight
ALUMINA
Crystallinity
SILICE
Plasicity Body
KAOLIN
9
1.21%
300gr.
2.68%
400gr.
1.79%
400gr.
0%
150gr.
7
1.22%
200gr.
2.11%
300gr.
.53%
300gr.
0%
100gr.
10
18%
100gr.
1.12%
200gr.
1.26%
200gr.
.98%
75gr.
Microoganisms used in biofiltration of air
40
Test 2
Test 1
Bioactive Ceramics
8
5.85%
Components % present on the mixture
7.92% 8
50%
Silice 11%
50%
Feldespat 12%
30% 40%
30%
40%
Water % present on the mixture
Silice 20%
10% 20%
10%
20%
Clay 48%
Clay 48% Kaolin 20%
Test 2
Test 1
Feldespat 30%
Kaolin 11%
Absorption %
Silice .2%
Clay 43%
Test 3
18% 8
Silicate .3%
50%
40%
30%
20%
10%
Calcium 10%
pH Scale
Feldespat 40%
Kaolin 6.5%
Materials and Methods
Figure 3.2.2b Ceramic second exploration; Porosity test ll.
41
Bioactive Ceramics
Second Exploration (Figure 3.2.2b) The results of the last exploration gave us new insights about the base mixture and permit a new experimentation came to the analysis. In this second exploration we look to increase the absorption percentage and reduce the vitrification of the ceramic by reducing or replacing the flux materials such as feldespat to get ceramic pieces not so vitrified, and also increasing components that add body and plasticity to the mixture such as kaolin so the ceramic does not losses its mechanical strength that the flux materials give to the ceramic.
Image 3.2.2c Feldespat component.
Process This exploration consists in modifying the percentages of the components base mixture, reducing or removing the percentage of feldespat and increasing the percentage of kaolin and silica. The 48% of the clay that it is on the base mixture was kept as a non-modifiable variable because it gives the body to the ceramic. Test 1 The first test was mixed with a 40% of water and made with 48% of clay, 44% of kaolin, 8% of silica and 0% of feldespat. The results of the absorption test came presented a 2.94%, now the higher porosity yet throughout the exploration. This piece did not presented a good finish looking ,it has small cracks on it and a roughness that the last explorations did not showed.
Image 3.2.2d Silica component.
Test 2 The second test was also mixed with 40% of water and made with 48% of clay, 20% of kaolin, 12% of feldespat and 20% of silica, and presented a 3.52% of absorption, higher than the last mixture. Also this piece presented a worst finish, with bigger cracks on it and a fickle density on the body of it. The third test was made with 48% of clay, 11% of kaolin, 30% of feldespat and 11% of silica, and presented an even higher absorption percentage of 4.84%. This piece also presented a bad finish with bigger cracks and an inconstant density. (Images 3.2.2c,d,e,f)
Image 3.2.2e Absortion water test.
Conclusion As a conclusion, its visible that from the start of our exploration to this point that the absorption percentage has changed from a 0.5% to 4.84% or 7% which shows how the experimentation is taking a path towards a high porosity material and that altering the percentages of the components, reducing flux materials and increasing body materials increases the absorption percentages. (Figure 3.2.2g) Also, the high roughness and cracks of the pieces in this exploration were very visible on our pieces which affects the mechanical strength and finish of the ceramic pieces. Image 3.2.2f Absortion water test.
42
40%
6.GLASSING Spray varnish 30 sec. drying
8 hrs 1160ยบ
Flux & Strenght
FELDESPAT
KAOLIN
6.5%
7. HEATING
CLAY
43%
5. SANDING
Finished
CALCIUM
10% SILICATE
.3%
H2O
1. MIXTURE
20ยบ - 30ยบ 15hrs 80ยบ
4. DRY OUT
SILICE
Mechanical Strenght
.2%
1.2 MIXTURE
Clay Slip catsting
3. MOULDING
Net 200 6% Resistance
2. SCREENING
Materials and Methods
Figure 3.2.2g Selected ceramic mixture.
43
Bioactive Ceramics
3.3 Bacteria in ceramics In order to see how bacteria react in an open biofilter system with ceramic as bed medium, we made several tests in ceramics with a certain texture with different crest and valley sizes. (Figure 3.3a) Nine matrix of foamular were made in CNC milling with different sizes of valleys and crest and texture forms (Figure 3.3b) for the creation of the gypsum molds (Figure 3.3c) and therefore the slip casting of the different textures (Figure 3.3d) and so on for the application of bacteria on it. (Figure 3.3e)
In images 3.3 g, h, i and j the process of gel preparation is shown, in which the bacteria were inoculated in a gel medium of sodium alginate at 13%, with a pure vegetable colorant to use as a bacteria growth indicator. (Images 3.3k, l, m). We observed the growth and behavior of the bacteria and color in the ceramics during two weeks at an incubation at 30ยบC, during this time, the aqueous phase started to evaporate leaving the color in the dry ceramics. Also, the color change to a sky blue color, meaning that the bacteria were able to degrade the compounds present in the medium.
We observed the behavior of the gel and the bacteria during four weeks obtaining the following result (Figure 3.3f) in which we can see the lower depth (3.3) dry faster than the deepest (7.7) but which presented growth of fungi and also a change of color, following we chose the intermediate measure (5.7) for our project.
To test if the bacteria still on the surface and porosity of the ceramic, we took a sample from the surface with a hyssop and saline solution and cultivate into Petri dishes with nutritive agar and after 24 hrs at 30ยบC, we got a positive result obtained a growth of bacteria. (Image 3.3n)
3.3
3.5
3.7
5.3
5.5
5.7
7.3
7.5
7.7
Figure 3.3a Representation of the valleys and depth
44
Materials and Methods
3.3
5.3
7.3
3.5
3.7
5.5
5.7
7.5
7.7
Figure 3.3b Matrix of the valley and depth.
45
Bioactive Ceramics
Figure 3.3c Gypsum mold used for the textures.
46
Materials and Methods
3.3
5.3
7.3
3.5
3.7
5.5
5.7
7.5
7.7
Figure 3.3d Textures in ceramics.
47
Bioactive Ceramics
3.3
5.3
7.3 Figure 3.3e Textures ceramics with bacteria gel. (Start)
48
3.5
3.7
5.5
5.7
7.5
7.7
Materials and Methods
3.3
5.3
7.3
3.5
3.7
5.5
5.7
7.5
7.7
Figure 3.3f Textures ceramics with bacteria gel. (Last)
49
Bioactive Ceramics
Image 3.3g Elements for gel preparation.
Image 3.3h Weight of the sodium alginate.
Image 3.3i Vegetal colorants for colouring the gel.
Image 3.3j Finished color gel.
Image 3.3k Inoculation of ceramic texture with gel.
Image 3.3l Inoculation of ceramic texture with gel.
image 3.3m Inoculation of ceramic texture with gel.
image 3.3n Obtaining ceramic bacteria sample
50
Materials and Methods
3.3
5.3
7.3
3.5
3.7
5.5
5.7
7.5
7.7
Figure 3.3o Bacteria culture from the ceramics textures.
51
Bioactive Ceramics
CO2
3.4 Open biofiltration system efficiency
CO2
H2O
CH3 O O H3C
OH H3C
1-PROPANOL
COOH COOH
MUCONIC ACID
OH CH3
CH3
H
OH
OH CH3
Figure 3.4 VOCs and BTEX degradation pathway and its final products.
52
OH
COOH COOH
MUCONIC ACID 4-METHYL CATECCHOL O-XYLENE DIHYDRODIOL
CH3 H
CH3
O-XYLENE
OH
CH3
CH3
CH3 O
OH
OH
CATECHOL ACETOPHENONE 1 PHENYLETHANOL
ETHYLBENZENE
COOH
CHO
CH2OH
CH3
BENZALDEHYDE BENZYLALCOHOL
OH H
OH
COOH COOH
BENXOIC ACID
O
OH
OH
PORPIONATE
CH3 H3C
O
O
PROPIONATE
SUCCINATE CATECHOL
OH O
H2O
CO2
CO2 H2O COOH COOH
O
OH OH
MUCONIC ACID
OH H3C
O
ACETIC ACID SUCCINIC ACID
O
2 OXOADIPIE ACID
O
MUCONIC ACID
OH
CATCCHOL
OH H
BENZENE DIHYGRADIOL
TOLUENE
Our biofilter helps in the VOCs’ degradation and BTEX, synthesizing them in simple by-products, having as a final result CO2 and H2O. CO2 can be synthesized in oxygen by surrounding vegetation. (Figure 3.4)
BENZENE
Other microorganisms inevitably grow within the gel, but the growth of other species enhances the performance of the biofilter.
-O
Our biofilter is open and has a passive filtration. The efficiency in a high concentration of contaminants is between 70% - 90%, according to research papers, the bacteria quantity, and its characteristics.
O
In our project, the quantity of bacteria applied is 50 ml of bacteria culture (UFC were counted resulting in 1x10^6 UFC/ml in each flask) in 450 ml of sodium alginate gel with 60 microliters of vegetal colorant (30 microliters - Red, 30 microliters - Blue) to reach a purple color, which is going to act as a colorimetric assay. If the gel turns to a sky blue color, it means the degradation process is being performed.
O
The decomposition of 1 kg of a hydrocarbon produces 1.5 kg of water. To ensure an efficient process of pollutant biodegradation, the packing material’s humidity has to reach 40% up to 70%. To achieve an efficient performance of the biofilter, the humidity of the packing material has to reach 55%, while its porosity has to be 80%. [2.1b]
-O
One population of microbes suffices to degrade the VOCs. Microorganism’s adaptation to a biological packing material may take from several days to several weeks. Typically, the number of bacteria in a biological packing material can range between 106 and 1,010 CFU g−1. [2.1c]
CO2
Biofiltration is a VOCs degradation method that uses certain microorganism cultures. A cleaning efficiency of 90% has been achieved during previously made tests. [2.1c] Experimental tests with a VOC at different pollutant concentrations (from 0.12 to 0.71 g m−3) show a maximum pollutant removal capacity of 95%.
H2O
CO2
CO2
Considering the suitability, efficiency and cost-effectiveness criteria, currently, the most attractive cleaning method is the treatment of volatile organic and inorganic compounds with biofilters. VOC treatment using a biofilter is based on the biofiltration technique.
Materials and Methods
53
4.
Geometrical exploration
Environmental factors & Form finding
Bioactive Ceramics
Top view Top view
Front view Front view
Right Right view view
Figure 4.1.1 Water study diagrams.
4.1 Study of environmental factors
The behaviors of the rain water, water capillarity, sun path and the wind flow were studied to learn its specific characteristics, their properties and forms; and thus create a suitable geometry according to the studies performances.
4.1.1 Water study Water flow is part of fluid mechanics, its natural behavior (in the rain) goes vertically from top to bottom by gravity. Our goal with the figures we created was to make the fluid fall in a vertical direction so that the water particles could be deposited and stored in small containers and indirectly provide nutrients to our bacteria from the water. We investigated how we could indirectly feed our bacteria because if we did it directly we would run the risk that the abundant flow of water will take or drown the entire colony of it. Within our options we found that it could be done in different ways. The properties of ceramics, the material that we had previously chosen, we use in our favor, on the one hand we use their permeability which means the ability of a material to allow the passage of a liquid, such as water through rocks. Permeable materials, such as gravel and sand, allow water to move quickly through them, where as unpermeable material, such as clay, don’t allow water to flow freely. Seeing that the permeability of the material was not viable,
56
we took into account its porosity, a measure of the water-bearing capacity of subsurface rock. With respect to water movement, it is not just the total magnitude of porosity that is important, but the size of the voids and the extent to which they are interconnected, as the pores in a formation may be open, or interconnected, or closed and isolated. For example, clay may have a very high porosity with respect to potential water content, but it constitutes a poor medium as an aquifer because the pores are usually so small. At the end we choose capillary, means by which liquid moves through the porous spaces in a solid, such as soil, plant roots, and the capillary blood vessels in our bodies due to the forces of adhesion, cohesion, and surface tension. These properties also influence the direction that the geometry has, forming cavities or convex geometries. The behavior of the flow depends totally on that, we have decided to generate both to be able to regulate the entrance and exit of this. The spaces that have the most textured surfaces allow us to channel the flow of water, regulating it by means of them that also fulfill the function of obstacles. While concave surfaces are responsible for storing water in small amounts, allowing the capillarity of the material to comply with its internal runoff giving way to the water until it reaches our bacteria providing nutrients necessary for it to survive. (Figure 4.1.1)
Geometrical exploration
C e r a m i c
C e r a m i c
H2O
w a l l
H2O H2O
H2O
H2O
H2O
H2O
H2O
w a l l
H2O
H2O
H2O
Adhesion
Cohesion
Figure 4.1.2 Capillarity study diagrams.
4.1.2 Water study On the research, simulations softwares as Eve Rain in Rhinoceros 5 helped us to acknowledge different topics about the water behavior when falls inside the containers of the material, the entrance angles, and how to control the distances of water flow trajectory downward the material without getting to the bottom of it and avoid direct flow, drowning and fall of the bacteria. The diagram shows how the experimentation consisted on variations of simple curved lines on different heights representing the cavities. This curves get intersected with an external, imaginary circle that determines the angle flow in order to be able to alter its diameter and adapt the curve to the most optimal parameters, looking for a better water runoff. The most optimal angles where found on results with more than 5º. We investigated how we could indirectly feed our bacteria. Within our options we found that it could be done in different ways. The properties of ceramics, the material that we had previously chosen, we use in our favor, first we use their permeability which means the ability of a material to allow the passage of a liquid, such as water through rocks. Permeable materials, such as gravel and sand, allow water to move quickly through them, where as unpermeable material, such as clay, don’t allow water to flow freely. Seeing that the permeability of the material was not viable, we took into account
its porosity, a measure of the water-bearing capacity of subsurface rock. With respect to water movement, it is not just the total magnitude of porosity that is important, but the size of the voids and the extent to which they are interconnected, as the pores in a formation may be open, or interconnected, or closed and isolated. For example, clay may have a very high porosity with respect to potential water content, but it constitutes a poor medium as an aquifer because the pores are usually so small. (Figure 4.1.2) At the end we choose capillary, by which liquid moves through the porous spaces in a solid, such as soil, plant roots, and the capillary blood vessels in our bodies due to the forces of adhesion, cohesion, and surface tension. These properties also are influenced by the direction that the geometry has, forming cavities or convex geometries. The behavior of the flow depends totally on that, we have decided to generate both to be able to regulate the entrance and exit of this. The spaces that have the most textured surfaces allow us to channel the flow of water, regulating it which means of them that also fulfill the function of obstacles. While concave surfaces are responsible for storing water in small amounts, allowing the capillarity of the material to comply with its internal runoff giving way to the water until it reaches our bacteria providing the nutrients it needs to survive.
57
Bioactive Ceramics
MONTERREY
LATITUDE: 25.2034
LENGHT: -100.1176
R HOU
SUNRISE X 7:20
NTH, DAY MO
82.51°
TEMPERATURE X 24C°
WINTER NOVEMBER-MARCH SUNSET 18:00
41.66°
COLDEST JANUARY 5TH 10°C-21°C
X
SUNRISE X 6:50 TEMPERATURE X 32C°
SUMMER APRIL-OCTOBER
HOTTEST JULY 29TH 23°C-35°C
SUNSET X 20:30
X
AVERAGE
Figure 4.1.3 Solar study diagram.
4.1.3 Solar study The solar study began by analyzing the sun’s trajectory, its phases during the year and what were the average temperatures that have been recorded in a certain place where the geometry is to be placed. This study was done to identify the fixed variables that dictate the conditions in which the geometry will be found and how it will be altered to control the fixed conditions (light and temperature) and generate a geometry that has controlled conditions suitable to house the bacteria. The study was based on the average study of temperature, solar residence and sun trajectory as factors to be analyzed for the last 36 years (1980-2016) in the location of Estanzuela, Monterrey, Nuevo León, Mexico at latitude: 25.2034 Length: -100.1176, GTM-5, locating the solar inclination towards the south; With 41.66° inclination in winter during the months of November-March with departures from 7:20 hours and set at 18:00 hours, with a temperature of 24°C and dictating as coldest day on January 5 with min.10°C and max. 21°C. And the summer period with 82.51° inclination during the months of April-October, with departures of 6:30 hours and set of 20:30 hours, with a temperature of 32°C and determining as the hottest day on 29 July with min. 23°C and max. 35°C. From the data mentioned above, the extremities were selected, that is, the
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hottest day and the coldest day with the variable determined from 12:00 to 15:00 hours which is when there is more solar residence, this with the purpose that simulations and the results were more accurate and there were no inconveniences when determining the alterations and that did not correspond with the exceptions of limbs that occur in the selected location. (Figure 4.1.3) The following studies were carried out in ladybug plugin grasshopper in rhino, where shadows were simulated during the selected days, to locate which were the areas where I would have more residence and thus create folds or concavities so that these areas had shadows most of the time, after this study the solar residence was analyzed with the irradiation levels to identify in more detail where the alterations were necessary and to dictate what their depth would be, this analysis showed as a result kwh / m² that represents the accumulation of energy by the way weather. Given the results obtained and with the previous investigation of the conditions of the place, it was determined that the folds or the growth of the shadows must be established on the south side of the geometry since it is where the high levels of residence reach and on the side North must be zero because if I had them I would
Geometrical exploration
only give way to more heat, because another of the factors involved in the temperature of the environment in which it is in contact and here there is a convection heat transmission that is proportional to the area and increases heat receptivity; The above only determine the areas to develop and the strategies that can be taken is to change the orientation of folds that create shadows but at the same time have angles between 41.66 ° -82.51 ° which are those that develop the summer and winter periods , in summer they are higher to create more shade in vertical and decrease the temperature in these areas on the surface and winter that these angles do not affect the receptivity of light and this achieves the appropriate temperature capture for the organism.
4.1.4. Wind study Wherever water exists, it tends to take a spherical form, it envelopes the whole earth in a thin layer, we always found moving water, seeking for a lower level, following the pull of gravity. The ways fluids move depends always on gravity, a sphere is a totality, a whole, it will always attempt to form an organic form by joining what is divided and uniting it in circulation. Water is essentially the element of circulatory systems, the cycle through the solid, liquid and gaseous phases may be counted among the best known circulatory processes of water. Rising from oceans, lakes, and rivers, it circulates with the air in the great atmospheric currents around the earth, it enters cooler zones and contracts into clouds and falls back to earth as dew, rain, snow or hail.
Quadrangular surface
As we shall see, every stretch of water, every sea and every natural river has its own circulatory system, this invites us to see the earth as a vast organism. The plant world plays a special part in the great circulation of water. The plants are vascular systems through which water, the blood of the earth, streams in living interplay with the atmosphere. Together earth, plant world, and atmosphere form a single great organism, in which water streams like living blood. A brook running through a meadow makes many small often only tentative bends. Stream and surrounding terrain always belong together, and the vegetation unites both in a living totality. The meandering flow of water is woven through with a play of finer movements. These result in manifold inner currents that belong intimately to the life and rhythm of a river. As well as the movement downstream there is a revolving movement in the crosssection of the river. Contrary to a first superficial impression, the water not only flows downwards but also revolves about the axis of the river, so as well as currents flowing downstream there are also revolving currents in the bed of a stream. (Figures 4.1.4) A black box is a measurement tool used to simulate wind flow, this works by an input and output, which determines where the wind comes in and where it goes out, this gives the possibility of choosing the velocity and itineration of the wind, within the black box a solid body will be case of study for how the wind impact over it and determines what the natural flow will be. Between the input and output are the walls that work as a tube for the wind, it directions the winding course and creat the 6 faces box, within the box a serial number of physical and mathematical solutions gives us a graphic result for the simulation.
Figures 4.1.4 Studies of wind flow
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Bioactive Ceramics
4.2 Form Finding Prototypes
Different architectural elements were chosen for form finding geometry, for each one of the applications different techniques were used to generate the specified envirnomental conditions, through textures, geometries, forms, etc., with the purpose of analyzing in each one its behavior of natural conditions and thus being able to define the parameters of shape, configuration, assembly, size, orientation, depth and texture density that the final geometry should have for the optimal required conditions.
4.3 Voronoi diagram
A Voronoi diagram consists in the partition of a given plane into regions based on the distance to points in a specific delimited subset of the plane. These regions are called Voronoi cells, explained in a more simple way each seed generates the region based on the increase of a circle, as it does consecutively in each generator depending on the mapping of the seeds each circle grows until each one adjoins until the increasing made every circle curve a wall of the cell. Founding inspiration from nature is elementary to generate an optimal bio-integrative design. From the forms of dry earth cracks, the cellular composition of plant leaves, even in bubbles concentration or the anatomy of insects wings. We can find similarities between these examples and the voronoi cells. To substain the implementation of this diagram, the design geometry comes from the properties these form can give, while we explore how these patterns work with a volume in the need of water capitation, direction of the air, concentratation of humidity, all inset to generate the optimal conditions to harbor microorganisms in architectural elements. To generate the geometry we come across with limiting factors, these are determined by the environmental conditions where we’re working on, to adapt the geometry to use conditions in our advantage, so we can exploit the extreme environmental factors to be used as resources. For example, water from rain, the heat factor, light from the sun and natural wind currents can contribute to the optimal function of the result element, to be able to take advantage of the elements in extreme environmental conditions, we need to have clear how we are going to control these elements in our favor, in this case, would be the storage of water, the shadows from the sunlight and how to canalize the airflow.
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With the patterns that Voronoi diagrams generate, we can emulate a fluid path from nature, by having the ability to alter the Voronoi cell patterns by sections within a plane, we can generate a cell size gradient and so change the geometry of the polygon, to obtain different lengths and angles of the polygon edges. Having this knowledge and experimenting with these parameters, we can notice similarities between the geometry generated with the form of veins and roots, that are naturally fluid carriers. Now to obtain our experimental geometry result, its necessary to implement the computational design. The 3D models of the first geometry exploration start from a rectangle surface generated by two different distances in axis X and Y, which would be our given plane for the subsequent partition of Voronoi cells. The location of the points in the plane can be preestablished by a pattern or by selectected points population. Once you have the delimiting plane and the points in it, the cells are generated and the plane is divided into the number of points established before, which will provide a certain quantity of closed polygons. When all the closed polygons are transformed into surfaces which contains a self mesh, we have to generate a point in the center of the surface area to move it in Z-axis and a pyramid can be created by the pulling of the surface mesh. The properties of a pyramid contain hard edges and vortex generating conic or peak forms, to achieve the final form each geometry is smoothed trough the Catmull-Clark algorithm, a technique used in 3D modeling to smooth surfaces by using a type of subdivision surface modeling. The height points are controlled by attractor points. This consists of a point located in a plane with a point population that can recognize the closest or more distant points. These attractor points are subdued with rules made by a norm bound domain designed by code. As a result, the final variation control parameters are area and height of the surface, population quantity by section, and attractor points number. The diagrams presented (Figures 4.3) are explorations developed with different attractor lines and external figures such as the variation of a rectangle to a hexagonal polygon, with the intention of obtaining different results. Our initial objective was to design geometries to house bacteria, that to create a space in which the bacteria can live and grow. We take in count the environmental conditions such as the flow of water, the shadows the figures generate and how the wind pass through them.
Geometrical exploration
The first exploration was a simple voronoi diagram to understand its function, a rectangle was made in which we played with the depth of the channels that are generated between each polygon to see if it was feasible to take it as a factor so that the bacteria could develop there. Seeing that it was feasible, we continued doing explorations and added a kind of wells to concentrate them in a single space and around them the larger cells would serve as walls to prevent the wind from drying out the bacteria’s habitat. Later we generated figures with more complex designs within a hexagon that are still polished to have more options designs for modular panels.
Step-Jump controls the time of growth of such factors (The Step must be higher than Jump for obtaining better resolution). To define the parameters in which it was started to analyze, we based on mitosis (a procedure of cell reproduction that consists in the division of chromosomes and nuclear division of the cytplasm, feed: 0.0367 kill:0.0649) and the degrade-coral (feed:0.01-0.1 kill 0.045-0.07). After obtaining this data, each of the factors previously mentioned were modified and their reactions were analyzed for each factor alteration.
The channels that carry the water to the center have been explored, placed in that position to regulate the entry of the water and to be able to direct its flow; the center, where the final home for the bacteria is planned, here the concave geometries were generated so that the material can trap and absorb the water and the volumes of its surroundings. The different elevations will be responsible for generating shadows. The cells of the center and the surrounding surfaces (flatter) will have the function of a windproof wall such as regulating the entry of water and generating shadows for the small channels that are between them.
It was observed that if the alterations in which the mitosis was applied had vertexes and edges in the negative base of growth, the mitosis starts from cero and it has no cavities, which means that it only grows in branches from its vertices. Likewise, if the negative base is just one solid or linear piece, it grows in a conic way with interior branches without interactions between them. Also, if the negative contains a figure within another figure, each one can develop branches in an independent way, it doesn’t present inferior concavity from the start, similar to figures with vertex.
4.4 Reaction Difussion Reaction Diffusion concept To design a vertical object that distributes inside its structure conditions for a microorganism to live in; this object was developed with a grasshopper code that represents the growth of reaction and diffusion. We use the concept o , chemical reactions and diffusion. The chemical reactions provoke a transformation — the consumption and production of molecules. On the other hand, diffusion provokes expansion — the movement of molecules. This procedure was applied on the projection over a negative base which makes a growth in branches and continuous housing. The mentioned code consists of several factors: a negative base of 1080x1080 px with elliptical, linear and solid figures; from which the growth departs. Feed, which means the feeding-production. Kill, which is the grade of consumption-movement of cells. Da and Db represent the heterogeneous substances and how they react, these two factors control the size of the cell.
Mitosis behavior
However, if the negatives are elliptic figures or with curve vertex, there is growth of continuous housings and internal branches that join with the inferior part. Finally, if the negative contains a figure with high thickness, it only takes its outline and develops a double growth, solid branches on its exterior without union and continuous housings in its interior.
Degrade-coral behavior It was also observed that the feed must not be superior to the kill because it leads to a saturation that prevents its growth. The negatives that the figures contain and the fact that they don’t present a connection between them create a solid growth on the interior with internal setoffs similar to morphologic channeling. From the feed: 0.03 and kill: 0.06, there are growths with waves that grow from its center and degrade, while they create an impact, when close to the extremities. These behaviors are produced when Kill has a range of 0.06-0.07 and in the feed: 0.03-0.1, but this last one decreases proportionally to the increase of Kill, for example: if the growth in degradation is presented when the kill is 0.06 and the feed is 0.03, if Kill is 0.061 then it will begin to present growth when the feed is 0.05.
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Bioactive Ceramics
Prototypes Prototype 1° Objective: To design a vertical element that takes into account a layered development towards its interior and that each of the layers meet the following objectives: the exterior must act as a windbreaker, the one next to this one must create an air pocket to regulate temperature, behind this concavity is where the organism sprouts, and finally, canalizations in its interior for water retention to maintain moisture. Development: Growth tests were performed in mitosis (with the circular negative with a bigger width) and degradation (with a double-digit negative), to later select growths of mitosis that met the windbreaker function, and the degradation one that met the canalizations and concavities for sprouting, and the fusion between them will create the air pockets for temperature regulation. To create a continuous vertical element, a cut was made on the top part due to the curvatures on the extremities it presented and this provided stability when fusing with another, continuous to the cut a vertical mirror was made that later fused to create a single element that has a recollection on the top and a disembogue on the bottom and also meets the stability requirements to be able to receive another element. (Images 4.4 a,b and c) Conclusions: The exterior shell growth had differences at the moment of fusing the mirror of the figure, on every side, it presents differences in the concavities and formations that can be interpreted for the support in the redirection of the air according to the orientation of its placement. (Figures 4.4)
4.5 Folds
Column exploration
The strategy used for the development of this geometry similar to that of a cylindrical column element that is exposed in all directions. Taking as reference the folds that exist in nature that can be detected in rock deformations, as they develop concavely and convexly, creating patterns that cause shadows and channels that are the characteristics that are being sought in geometry to create a condition for the organism. (Images 4.5 a, b, c, d, e, f) The development of this geometry arises from the subdivision of a circle, these being the axial axes of the syncline and anticline ends that vary in height and opening height, then three or more of these folds are generated and placed at different heights, being these sections that will result in the height of the concavity, then intercalate and redirect syncline hinge with anticline to last join them and result in a geometry that results in a horizontal development as vertical hinge synclines as anticline. (Figures 4.5)
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4.6 Bernoulli Wind Tunnel Exploration form The geometry of the piece started with the rule of the Bernoulli wind tunnel, continued with a symmetrical geometry, then more square and then more triangular, the frontal size is 35 x 35 cm and a 35 x 15 cm plant, all of the same size based on a standard measures wall, the form was varied to test assemblies and the symmetry was removed, the same parameters were what led to the final form. For stability, it was designed with the widest part at the top and thin at the bottom to emboss, on the lateral side it doesn’t matter if it is inverted, so you have more support from one piece to another. The geometry of the center began with the diameter of inlet and outlet of the same size, then it was based on Bernoulli’s principle by varying the diameters of inlet and outlet from greater to lesser, so the wind comes out with less pressure and greater speed, also the size of the area was varied with respect to the size of the figure, the first tests being from 5 to 20 cm, from 10 to 12 cm and obtaining the best hole diameter of the final tunnel from 8 cm to 18 cm; thus also respecting the most optimal area for the placement of the bacteria. (Images 4.6 a, b, c, d, f, g, f) When the geometry crosses the tunnel, the surfaces go 1 cm from one side and the other 6 cm, leaving space for water runoff. Likewise, the distance between the first hole and the last one according to the geometry, generate the necessary shadow, tests were made and the amount of shadow with the size of the tunnel and the piece proved to be efficient. The internal textures of the tunnel vary between 3, 5 and 7 mm between valley and ridge, thus obtaining 9 tests in total and the texture with 5 of valley and 7 of crest was selected because it was the average measure in which no It dries so much and is not so wet for the cultivation of microorganisms. The porosity and the amount of water that can hold the texture were also taken into account, as well as the adjustment for cutting and production of the piece, the texture was divided into 2 sections, in the gradient of the texture the bottom center is for the water runoff, in the upper part is to house the bacteria and where textures are more present and are degraded from 100% to 75% and then while going to the bottom decreases to 10% and 20%, so the inferior texture generates a small stream and a minimum water retention so that the piece absorbs it by capillarity and the piece is wet and fed. This piece was embedded in a circular lattice in the form of a column since the lattice allows the passage of the air from which we want to degrade the contaminants so this architectural system is the most suitable for the purpose of our project. (Figure 4.6)
HOSTAGE
ROOF TILE
TEMPERATURE CONTROL
FACADE PANEL
WATER CHANNELING
LATTICE/ FACADE
WIND FLOW CONTROL
COLUMN
STRUCTURAL STABILITY
Geometrical exploration
Figure 4.2. Form finding and prototypes, based on architectural elements and environmental conditions.
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VOR (B) VOR (C) VOR (A)
VORONOI 64
Geometrical exploration
Figure 4.3 Voronoi diagram explorations and prototypes.
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REACTION DIFFUSION
Mitosis growth
Degrade-coral growth
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Negative input growth
Geometrical exploration
Figure 4.4 Reaction-Difussion explorations and prototypes.
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FOLD
=
2
5
4 1
6
3
DEPTH [1]
SINCLINALS (CONCAVE)[5]
AXIAL PLANE (AXLE) [2] WAVELENGTH [3]
FOLDS
FLANK [4] (DIVING-INCLINATION)
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ANTICLINES (CONVEX) [6]
Geometrical exploration
Figure 4.5 Folds explorations and prototypes.
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BERNOULLI WIND
TUNNEL V1
V2
A1 P2 P1 A2<A1
V2>V1
A2
P2<P1
RIPPLES SINE COSINE
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Geometrical exploration
Figure 4.6 Bernoulli Wind Tunnel explorations and prototypes.
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Bioactive Ceramics
image 4.5a Folds 3D printed explorations.
image 4.5b Folds 3D printed explorations.
image 4.5c Folds 3D printed explorations.
image 4.5d Folds 3D printed explorations.
image 4.5f Folds 3D printed explorations.
image 4.5d Folds 3D printed explorations.
image 4.6.a Bernoulli wind tunnel 3D printed explorations.
image 4.4a Reaction-Difussion 3D printed explorations.
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Geometrical exploration
image 4.6.b Bernoulli wind tunnel 3D printed explorations.
image 4.4b Reaction-Difussion 3D printed explorations.
image 4.6.c Bernoulli wind tunnel 3D printed explorations.
image 4.4c Reaction-Difussion 3D printed explorations.
image 4.6.d Bernoulli wind tunnel 3D printed explorations.
image 4.6.e Bernoulli wind tunnel 3D printed explorations.
image 4.6.f Bernoulli wind tunnel 3D printed explorations.
image 4.6.g Bernoulli wind tunnel 3D printed explorations.
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5.
Prototyping Molds & Ceramics
Bioactive Ceramics
5.1 Slip casting In order to understand how to elaborate our ceramic pieces, some prototypes had to be done to get conclusions and information about the fabrication process and what it is needed to change to get the appropriate geometries that the project requires. All these prototypes were produced inside CATO ceramics fabric. Slip casting is the process in which porcelain for architectural uses such as bathroom pieces and tiles is made with. It is basically the fabrication of molds with a cast to pour the ceramic mixture into it to generate a specific geometry. Our first approach to ceramic was done to explore the congruence of our geometries with the slip casting process, to analyze the techniques that are needed to apply the glaze to the ceramic pieces before the heating. Also, these initial prototypes where done to analyze the shrinkage of the ceramic pieces that happens when the pieces are cooked, so the scale can be understood and our matrix geometries are designed with these percentages.
Mold Fabrication This process was the solution for the prototyping exploration of the ceramic pieces. Cast molds where fabricated in order to be poured with the ceramic mixture and expel the water of it so it can dry to get cooked. The cast absorbs all the water and left the pieces dried because it works just as a vehicle for the mixture to get its needed plasticity and stiffness. Using matrix geometries made of foam cut by milling process with a CNC machine already sanded and covered with vaseline the cast molds were done to get the negative geometries and be able to generate the positive ceramic geometries. The casting mold was fabricated with two holes, one for pouring the ceramic into it and the other for extracting the excess of the mixture on it.
Pouring, setting and drying of the mixture With the casting mold ready is now the time to pour the liquid mixture, with its optimal conditions inside the mold by using a funnel on one of the two holes the mold has, until the ceramic mixture comes out from the other hole, proving that the mold is full. Therefore, 40 minutes had to pass until the mold drops the liquid mixture left, leaving just a 9 mm layer of a dried and less plastic ceramic clay. Then wait for another 40 minutes to open the mold and remove the top part of it. Then wait for another 40 minutes to finally take the solid ceramic piece out of the mold and put through a drying
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process divided in 2, the first part at room temperature for about 12 hours, and the second part with industrial dryers at a temperature of 80ยบC for about 12 hours.
Glaze application When the ceramic piece is already dry, its time to sand it for clearing the imperfections the piece may have. Later on, it is ready to get the suitable glassing needed. The glass is made of refractories and funded materials that add strength, shine, foundation, and an extreme conditions-resistant layer to protect and give color to the pieces. In this case, the glassing process will be explored to get different results, with glass and porosities adjusted in specific points of the panels for the implementation of bacteria and its growth on it. The importance of the glaze on the project is because this recovering is antibacterial and is used in places where we do not want the bacteria to grow.
Heating Process The last process is the heating when the ceramic piece is already glassed, it is passed through an industrial oven for 14 to 16 hours under 1,160ยบ C, to get its final resistance, vitrification, and strength. When the pieces get cooked, they have to get cooled for 1 hour to have the final finished piece.
5.2 Prototype 1 The first prototype was thought of as a wall panel application. A 15x30x2.5cm rectangle. The ceramic pieces passed through all its industrial processes mentioned previously only modifying the glazing process, in which a standard of what needs to be painted was made for the correct painting of the pieces. Four identical ceramic pieces came out of the ovens but with a different percentage of glaze, information that came as a part of the analysis for the finished ceramic pieces. In this case, the analysis of the prototypes showed some points to continue working on the geometry design. One of the important points was about the exit angles. These angles need to be more smooth without closed edges and straight angles. Also, the fact that the cavities and the streams were not so functional because of the application it was thought to be, was seen on these pieces, so we started the water flow simulation process to understand correctly how does the water goes through and also analyzing the capillarity of the material. All these insights lead to making modifications to these geometries.
Prototyping
.
FORM FINDING
CNC MILLING
CAST MOLD
MIXTURE
PURING
DRYING
GLAZING
HEATING
Figure 5.1 Prototyping process.
5.3 Prototype 2 We follow this process into another prototype though also as a wall panel application of 60x60x2.5cm hexagonal geometry, now with different measures to analyze the behavior of the ceramic. This geometry was also put under exploration about the way it has to be glazed. New insights came also on this prototype principally based on the size of the piece and again on the exit angles and the functionality of cavities and streams for the water flow. This prototype showed that big size mold was not the very best option to be fabricated, the space between the top face and the bottom face was only 1.5cm on the inside part, so space inside was not the most optimal for fabrication. This leads us to try with a third prototype.
5.4 Prototype 3 This prototype was also place under the previous fabrication process. Now the geometry was thought for lattice application. The starting concept of this geometry was based on Bernoulliâ&#x20AC;&#x2122;s wind
tunnel principle, which states that an increase in the speed of a fluid occurs simultaneously with a decrease in static pressure or a decrease in the fluids potential energy. This was study and applied into a volume with a torus structure creating a very open and rounded tunnel from the front to the back of the geometry.After cooking this prototype, new details about the process came along. This geometry was able to be fabricated and ended up with a smooth finish. Also, it was resistant and very suitable for each one of the functionalities that the piece needs. Water flow simulations showed that the water flow was very efficient creating a fluent flow and letting the piece collect some water for it to get humid. Air simulations also showed that air flows in a very fluid way which is very optimal for the biofilter to work in the air and make it flow due to the geometry. All geometries were placed under analysis and by a sort of diagrams, simulations on this geometry showed the best parameters to generate the optimal conditions.
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Bioactive Ceramics
Image 5.2a Matrix.
Image 5.2b Gypsum mold.
Image 5.2c Pouring of liquid mixture.
Image 5.2d Glazing application.
Image 5.2d First prototype with different applications of glazing: (1) Finished piece without glazing, (2) Minimum glazing application, (3) Medium glazing application, (4) Full glazing application.
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Prototyping
Image 5.3a Matrix.
Image 5.3b Gypsum mold.
Image 5.3c Pouring of liquid mixture.
Image 5.3d Drying of the piece.
Image 5.3e Finished second prototype.
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Image 5.4a Matrix.
Image 5.4b Gypsum mold.
Image 5.4c Pouring of liquid mixture.
Image 5.4d Drying of the piece.
Image 5.4e Finished third prototype.
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Prototyping
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6.
Design Proposal
Final Geometry
Bioactive Ceramics
Image 6.1 Final piece representation.
6.1 Design proposal morphology
The geometry of the piece started with the rule of the Bernoulli wind tunnel, continued with a symmetrical geometry, then more square and then more triangular, the frontal size is 35 x 35 cm and a 35 x 15 cm plant, all of the same size based on a standard measures wall, the form was varied to test assemblies and the symmetry was removed, the same parameters were what led to the final form.
made and the amount of shadow with the size of the tunnel and the piece proved to be efficient.
For stability, it was designed with the widest part at the top and thin at the bottom to emboss, on the lateral side it doesnâ&#x20AC;&#x2122;t matter if it is inverted, so you have more support from one piece to another.The geometry of the center began with the diameter of inlet and outlet of the same size, then it was based on Bernoulliâ&#x20AC;&#x2122;s principle by varying the diameters of inlet and outlet from greater to lesser, so the wind comes out with less pressure and greater speed, also the size of the area was varied with respect to the size of the figure, the first tests being from 5 to 20 cm, from 10 to 12 cm and obtaining the best hole diameter of the final tunnel from 8 cm to 18 cm; thus also respecting the most optimal area for the placement of the bacteria.
The internal textures of the tunnel vary between 3, 5 and 7 mm between valley and ridge, thus obtaining 9 tests in total and the texture with 5 of valley and 7 of crest was selected because it was the average measure in which no It dries so much and is not so wet for the cultivation of microorganisms. (Figure 6.1a) The porosity and the amount of water that can hold the texture were also taken into account, as well as the adjustment for cutting and production of the piece, the texture was divided into 2 sections, in the gradient of the texture the bottom center is for the water runoff, in the upper part is to house the bacteria and where textures are more present and are degraded from 100% to 75% and then while going to the bottom decreases to 10% and 20%, so the inferior texture generates a small stream and a minimum water retention so that the piece absorbs it by capillarity and the piece is wet and fed.
When the geometry crosses the tunnel, the surfaces go 1 cm from one side and the other 6 cm, leaving space for water runoff. Likewise, the distance between the first hole and the last one according to the geometry, generate the necessary shadow, tests were
This piece was embedded in a circular lattice in the form of a column since the lattice allows the passage of the air from which we want to degrade the contaminants so this architectural system is the most suitable for the purpose of our project. (Figure 6.1b)
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8cm 18 cm
TEMPORAL SHADOW
10cm 12 cm
PERMANENT SHADOW
58340.372 mm2
5cm 20 cm
x
+Velocity
Bernoulli
- Pressure
x
x
WINDFLOW
15%
15%
100% water free
WATER CHANNELING
100% shadow
TEMPERATURE CONTROL
75%
75%
10%
100%
(TEXTURE)
% CAPILLARITY
4.2
/s
7 mm 5 mm
7 mm 3 mm
m
5 mm 5 mm
3 mm 5 mm
5 mm 3 mm
3 mm 3 mm
Valley mm
Depth mm
2.1 m/s
velocity
7 mm 7 mm
5 mm 7 mm
3 mm 7 mm
TEXTURE
50% wet
50% dry
HOSTAGE
2.1 m/s confort velocity hostage area
WIND FLOW CONTROL
150mm
350mm
350mm
SIZE
(TOTAL PIECE)
GEOMETRY
selfsupporting
STRUCTURAL STABILITY
Design Proposal
Figure 6.1a Final piece morphology.
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COLUMN ASSEMBLY
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Figure 6.1b Column assembly.
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LEFT-RIGHT
LEFT-RIGHT
LEFT-RIGHT
TOP
TOP
TOP
BOTTOM
BOTTOM
BOTTOM
Design Proposal
Figure 6.2.1 Water study on column lattice and piece wring.
6.2 Environmental factors simulations
6.2.1 Water study
To verify the application of the design strategies for the principles of environmental factors on the defined geometry, different softwares were used to probe the design piece efficiency.
For the water simluation and the runoff of water drops, it was necessary to take into account how the pieces were going to behave together and separately.
The Ansys program was used for wind simulations on the lattice column, in which we obtained differente results according to the Bernoulli wind tunnel, as well for the lattice and column form.
As a whole, the goal was for the fluid to have a trajectory that prolongs the time in the piece, since the longer it is traveled, the absorption increases thanks to the capillarity of the area that does not contain glazig, this area was designed with a profile at a radius of 1 cm.
In the solar study, we input as reference the site location where the column is built, with the Grasshopper Ladybug plug-in we obtained the solar simulation of the whole year from the different cardinal points. For the simulation of fluids, in this case water, the rhino 6 eve plugin, was used to determined, how the rain water will flow on the column lattice and how it will drain the design finished piece.
Which is consistent with the principles already seen in the studies of fluids and the operation of the capillarity, which cause that the area to be housed does not have contact with water, but has that humidity through material that retains the water absorbed by the capillarity (Figure 6.2.1)
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PERMANENT SHADOW
TEMPORAL SHADOW
EAST
NORTH
WEST
SOUTH
Figure 6.3.2 Solar study on column lattice.
6.2.2 Solar study In order to control the sun exposure of the area where the bacteria will be, it was tested with different distances in length from the tunnel in which the bacterium was to be found, with the purpose of reaching the length that would result in a shadow permanent throughout the year and any orientation in the area to be housed, this to control the temperature generated by the area through the shade.
The test is based in the black box principle, where we have a fluid, walls tunnel, an inlet wind speed and outputs results, where our solid is in the middle of the box being impacted by a fluid who reacts to the solid as in real life, throwing us results as streamlines, speed, etc. We made the test over one of the column geometry to test the holesâ&#x20AC;&#x2122; texture functionality, we needed to know if the microorganism will not be thrown away by the air or water.
With the previous study of environmental factors it was determined that the north and east orientations are discarded for the determination of the length of the tunnel, since in these zero solar exposure is presented, leaving as orientations to analyze south and west, giving as a result of the experimentation a length of 15cm, reaching 100% of the area to be housed (Figure 6.2.2).
Image 6.2.3a We can see a front view of the model, the colored surface edges representing the boundaries of the wall tunnel, same as the airflow contours represented in the different colored surface, in image 1 simulation the air just started going through the face of the 3D model. Image 6.2.3b To understand the contours, we must know that the lighter blue colors represent the lower speed, as they get darker they start turning purple ending up on a lilac color that represents the highest airspeed. As we can notice from image one and two the wind speed starts very low and increases through the tunnel. Image 6.2.3c. In this image, we realize the speed increases noticing the color within the tunnel start becoming purple and lilac, but just by the edges, it stays light blue. Image 6.2.3d We proved that the bacteria located in those areas are safe from being carried away from wind by the lumps that decrease the wind speed.
6.2.3 Wind study
Using Computational Fluid Dynamics (CFD) simulations, we can know how fluids behave over a solid given by a 3D model, to be certain about how environmental conditions as wind and rainwater will impact our pieces, and prove the bacteria is safe to live, promoting degradation of volatile organic compounds. (Image 6.2.3e)
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V
V
V
Image 6.2.3a Front view section 1
V
Image 6.2.3b Front view section 2
V
Image 6.2.3c Front view section 3 V
Image 6.2.3d Front view section 4 V
2.1 m/s 2.1 m/s
4.2 m/s V
4.2 m/s
V Image 6.2.3e Isometrical view.
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Image 6.1c and d. 3D printed prototype of the column lattice.
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Image 6.1e Representation of the final prototype.
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Production
Fabrication Process
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7.1 Fabrication Process 7.2 Milling strategy
With the textures analyzed and final geometry of the pieces decided, a Gcode was made with rhino cam to cut the foamural pieces that will be the matrix of our ceramic pieces for the mold fabrication. After the milling of the material with a CNC router the 12 pieces that create one of the geometries had to be pasted and covered with glue with its necessary repair already done.
image 7.2a Milling on CNC of the final piece.
7.3 Gypsum mold fabrication For the mold production, it was necessary to develop on a way in which the piece won´t get messed up when the unmold is done. For this, the mold was divided into different sectors, each one with a different unmold path, one sector on the center, another on the surface, and one more sector that creates the assembly areas. Three gypsum molds were fabricated each one in 5 days for the corresponding pieces that the final exhibition was requiring. 7.4 Mixture Casting and drying process For pouring the mixture into the molds, they have to first get the correct treatment with feldespat and water for the piece not to get stuck to the mold and be assembled and closed properly. After this the mixture is poured by cones into one entrance of the mold. From this process 80 minutes had to pass to drain the mold and let the leftover mixture come out of the mold. Then the piece needs 40 minutes to be opened from one side, then in another 40 minutes place the rest mold and turn the mold into it so the piece gets out, finally the four central pieces need to be taken out . Then the mold is ready to be assembled, closed and poured again. 7.5. Glaze application The glaze application comes after the pieces get the correct sanding and drying in the industrial dryer above 80ºC. The pieces need to be free of glaze in the areas of the assembly and the textures. For this, some mdf covers were made so at the moment when the glaze it’s applied with a paint gun those areas are not painted. From here the pieces are ready to get the heating treatments on the oven above 1160ºC.
image 7.2b Final Matrix.
image 7.2c Matrix of the texture.
This process had to be made for 57 ceramic pieces for the final exhibition to be made, fabricated on 4 weeks in which were fabricated from 4 to 5 pieces each day trying to pour from 2 to 3 times each day in sessions of about 3 and a half an 4 hours each.
image 7.2d Matrix on the gypsum mold.
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image 7.3a Gypsum mold production.
image 7.3b Gypsum mold tunnel texture production.
image 7.3c Gypsum mold tunnel texture production.
image 7.3d Finished gypsum mold.
image 7.4a Closing the gypsum mold with metal strings.
image 7.4b Pouring of the mixture in the mold.
image 7.4c Draining of the excedent of the mixture.
image 7.4d Casting of the pieces.
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image 7.4f Resting of the pieces. (Back side)
image 7.4g Resting of the pieces. (Front side)
image 7.4h Resting of the pieces.
image 7.4i Pieces production.
image 7.4j Drying of the pieces in the drier.
image 7.4k Drying of the pieces off the drier.
image 7.5a Glazing of the pieces.
image 7.5b Baking of the pieces out of the oven.
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image 7.1 Finished pieces assembled.
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Installation
Exposition Area
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Exploded Isometric viewExploded Isometric view
8.1 Installation For the final exhibition of the designed pieces it was thought to create three wooden bases to show the prototypes developed during the experimental process to reach the final prototype. These were cut into 30mm mdf on the CNC machine, then nailed to a waffle structure to support the bases. They were then sanded, hung over, sealed and painted with white paint. (Figures 8.1 a, b, c and d.
Figure 8.1a Exploited isometric view diagram of the base for display. It shows all the elements that shaped its construction. From the base, the waffle structure, the basis for geometry and geometry. 102
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Base 1
Base 2
Base 3
Figure 8.1b Top view of the three bases that make up the exhibition and their respective housed prototypes.
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Top view
Entrada CEDIM
Figure 8.1c Map of the location of the three bases outside the CEDIM entrance.
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Figure 8.1d Representation of the three columns outside the CEDIM entrance.
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Bibliography 1.1a. Vitruvio, De achitectura, Chapter 1, Book 6. 1.1b. William Myers. Thames & Hudson, (2012) Bio Design: Nature, Science, Creativity. - Architecture and biology - 288 pages.
2.3c. Van der Steen, J. B. (2013). The general stress response of Bacillus subtilis.
1.1c. Montaner, J. (1997), La modernidad superada, 191 pages.
3.1a Earl, A. M., Losick, R., & Kolter, R. (2008). Ecology and genomics of Bacillus subtilis. Trends in microbiology, 16(6), 269–275. doi:10.1016/j.tim.2008.03.004
1.4a. http://syndebio.com/wp-content/uploads/2013/07/Pike_Contaminant-1.jpg
3.2 Ceramics. https://www.sciencelearn.org.nz/resources/1769-what-are-ceramics
1.4b. http://syndebio.com/biq-algae-house-splitterwerk
3.3 sergio Hernandez (2011) Inmovilizacion de microorganismos en esferas de alginaro. https://cibnor.repositorioinstitucional.mx/ jspui/bitstream/1001/223/1/hernandez_s.pdf
1.4c. https://publiekgemaakt.nl/bomenkwekers-en-kunstenaarswerken-samen-aan-de-mooiste-rijksweg-van-brabant/The Bio-Integrated Design Lab at the Bartlett School. 2.1a. Baltrėnas P, et al. (2016) A biochar-based medium in the biofiltration system: Removal efficiency, microorganism propagation, and the medium penetration modeling, Journal of the Air & Waste Management Association, 66:7, 673-686, DOI: 10.1080/10962247.2016.1162227. 2.1b. Rakesh Govind, (2009 ) BIOFILTRATION: AN INNOVATIVE TECHNOLOGY FOR THE FUTURE, University of Cincinnati. 2.1c. Thakur Prabhat Kumar, (2011) Biofiltration of Volatile Organic Compounds (VOCs) – An Overview. Research Journal of Chemical Sciences ISSN 2231-606X Vol. 1(8). 2.1d. Yang Lu, et al. (2010) Study on the removal of indoor VOCs using biotechnology, State Key Lab of Urban Water Resource and Environment. School of Municipal and Environmental Engineering; Harbin Institute of Technology; China. 2.3a. Muter, O. et al. (2012) Comparative Study on Bacteria Colonization onto Ceramic Beads Originated from Two Devonian Clay Deposits in Latvia. Materials Sciences and Applied Chemistry. Vol.26, pp.134-140. ISSN 1407-7329. e-ISSN 2255-8713. 2.3b. Jūratė Repečkienė, et al. (2015) Succession of microorganisms in a plate-type air treatment biofilter during filtration of various volatile compounds, Environmental Technology, 36:7, 881-889
4.1.2 Water capillarity - https://www.britannica.com/science/capillarity 4.3 Franz Aurenhammer, Rolf Klein & Der-Tsai Lee (2013) “Voronoi Diagrams and Delaunay Triangulations”. World Scientific, 2013, 337 pages, ISBN 978-9814447638 4.4 Reaction-Diffusion Tutorial, Karl Sims (2019), http://www.karlsims.com/rd.html 4.6 Bernoulli wind tunnel. http://vlab.amrita.edu/?sub=77&brch=297&sim=1671&cnt=3605
Image references 1.1a. http://terceravia.mx/2018/01/la-contaminacion-humana-inicio-mucho-la-revolucion-industrial/ 1.1b. http://www.good2b.es/la-arquitect ra-de-frank-lloyd-wrightpatrimonio-de-la-humanidad-segun-la-unesco/ 1.1c. https://explorebiotech.com/biocement-the-cracks-on-yourbuilding-can-actually-heal-itself/ 2.4 http://nimetng.org/product/detox-blox-bio-filter-media-formarine-and-freshwater-aquariums-6x6x2-2-pack/
Monterrey, Nuevo Leรณn 2019