Briefing Document by Cameron Worboys

a heterotopic view proto-typology [first,foremost,original] - [classification according to general type]

proto-typology [first,foremost,original] - [classification according to general type]

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manifesto

the overview effect - a cognitive shift Society has become disconnected from our world, we all live hyper-individualistic lives cut off from the complex network of driving forces behind our world. Living space is living space; no one is able to see how that environment is created, power comes out of the socket but in reality power doesn’t come from a socket at all. These boundaries of world are not natural they a created by our societies. We see daily examples where rational self-interest is used to justify wholesale destruction of community and environment, where shortterm profit override considerations for long-term consequences, where isolation seize our hearts despite being surrounded by more people than any time in history. People have begun to accept this thinking and rationale of the world presented to us in society. The overview effect is a bracket of philosophy developed by David Loy, it translates an ancient philosophy “videre quæ vos videtis, eos” you see things as you see things. This phrase suggests we see things we know but don’t experience them therefore we cannot truly understand them. The overview effect conveys the necessity of considering the big picture if we are to forge a sustainable future. We can easily traverse the surface of the world and remain unchanged. But stand on the top of a hill looking out, and things begin to look different. We begin to notice patterns on the landscape that were previously invisible. We find ourselves much more ready to think on grander scales and longer terms of our living recognising the fragility of our world. “A heterotropic view” suggests a new grand narrative, an understanding of our relationship with personal experience and the landscape. It recognises the interconnectivity between our world, we our not separate to the driving forces behind our environment. A shift in perspective is required and new way of looking at our world, a thinking against isolation, a new thinking for the future, seamlessly integrating nature, our resources, technology and our personal lives, a cognitive shift.

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“ Modern industrial culture doesn’t seem to have principles, except something like: “if brute force isn’t working, you are not using enough of it.” -Bruce Mau

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[04-39]

Contents The contents of this Document outline the process of brief creation. Vision & Ambition introduces the general interests of the project. The research phase outlines the processes required for the programme of the project. Approach & Instruction specifies the exact programmatic details of the project. Site analysis highlights the site strategy and context. The culmination of this document demonstrates detailed approach undertaken for the project.

vision.ambition

[40-59] research

[60-75] approach.instruction

[76-77] critical reflection / 5

vision.ambition history / water on canvey / industrial typology / heterotopia / water crisis

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re-imagining canvey island / 7

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Project Summary Canvey Island has been plagued by the influence of industry over its history. This industrial typology is associated with degrading the landscape rendering an undesirable architecture visually, culturally and socially. The resultant gap between the public-landscape-industry is the one â&#x20AC;&#x153;A Heterotropic Viewâ&#x20AC;? aims to bridge. The prototypology reinvents the industrial typology, through the creation of an industry prototype focused around solving one of the greatest problems in contemporary society, water shortage. The reinvention of the typology proposes the integration of explored Heterotropic elements and a naturally formed desalination solution. A large civic beachscape is seamlessly integrated with the industry as our connection between resources & leisure are strengthened in this imagination of future space. The new typology aims to create an architecture, which can stimulate the re-generation of Canvey Island whilst mentally transposing nostalgia of the once bustling coastline. Holding a strong connection with London proto-typology analyses the future water shortage, existing as a scalable prototype towards London. The project explores a new method of desalination using forward osmosis addressing the problem at this scaled down process. Importantly the architecture addresses key social and cultural issues associated with industry. The industrial process becomes the imagined dreamland as a by-product forms a crystallised landscape, (known as Haliteâ&#x20AC;&#x2122;s). The imagined image changes and adapts relative to the explored processes within the architecture, bridging the connection between the landscape and the architecture. This heterotropic view imagines a naturally driven industry, as an Utopian exploration of the future, simultaneously proposing a physical and mental imagination of space through the visual projection of the sustainable industry itself.

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History of Canvey Island

Canvey Island is a reclaimed island in the Thames estuary in England. It is separated from the mainland of south Essex by a network of creeks. Lying only just above sea level it is prone to flooding at exceptional tides, but has nevertheless been inhabited since the Roman invasion of Britain. The island was mainly agricultural land until the 20th century when it became the fastest growing seaside resort in Britain between 1911 and 1951. / 12

The North Sea flood of 1953 devastated the island costing the lives of 58 islanders, and led to the temporary evacuation of the 13,000 residents. Canvey is consequently protected by modern sea defenses comprising 15 miles of concrete sea walls. Canvey is also notable for its relationship to the petrochemical industry. The petrochemical Industry has investing heavily in Canvey and now is considered the dominant industry and land form on the island.

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â&#x20AC;&#x153;heterotopia of illusion creates a space of illusion that exposes every real space.â&#x20AC;?

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Heterotopias - Michel Foucault

Heterotopia is a concept elaborated by philosopher Michel Foucault to describe places and spaces that function in non-hegemonic conditions. These are spaces of otherness, which are neither here nor there, that are simultaneously physical and mental, such as the space of a phone call or the moment when you see yourself in the mirror. A utopia is an idea or an image that is not real but represents a perfected version of society, such as Thomas More’s book or Le Corbusier’s drawings. Foucault uses the term heterotopia to describe spaces that have more layers of meaning or relationships to other places than immediately meet the eye. In general, a heterotopia is a physical representation or approximation of a utopia.

www.vimeo.com/54021036

“A Heterotropic View” interprets three heterotropic principles: ‘Heterotopia can be a single real place that juxtaposes several spaces. A garden is a heterotopia because it is a real space meant to be a microcosm of different environments with plants from around the world. ‘Heterotopias of time’ such as museums enclose in one place objects from all times and styles. They exist in time but also exist outside of time because they are built and preserved to be physically insusceptible to time’s ravages. ‘Heterotopias has a function in relation to all of the remaining spaces. The two functions are: heterotopia of illusion creates a space of illusion that exposes every real space, and the heterotopia of compensation is to create a real space--a space that is other.’ / 15

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Water on Canvey Canvey Island is located on the mouth of the Thames Estuary. Since the island was drained in the 14th Century by the Dutch the very existence of Canvey Island relies of a complex network of water systems. With over 136 drainage channels to date and 12 large mechanical pumping stations keeping Canvey dry is not a easy project, a variety of water inputs feed Canvey is millions of megalitres of water a day, including, tidal inlets , powerful river catchment and

most importantly rain water. The water network has to strike a balance between freshwater extraction and sea water exclusive. Surrounding by a 3m metre high sea wall around the entire island Canvey is often referred to by artists and poetics as the inland lake. The Canvey water system is approximately made up of 75% freshwater and 25% sea water. To control this network of intensive pump houses and drainage channels form the

island. These pump houses control the water in Canvey to the best of their ability balancing the different inputs highlighted to the right. Despite the complex nature of this system Canvey stills struggles to find a balanced equilibrium of water, often flooding. 57% of freshwater is land locked on the Island through failed gravity outfalls, 49% of water on the is pumped off the island mechanically and 35% of the year sea water has blocked the system.

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Fresh-Water Channel

Canvey Water Map

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Sea Water Infiltration

Pumping Station Pressures

Rainbow

Anterlers Outfall Systematic Connections. (SITE A)

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The average person in the UK consumes 165 litres of water per day.

2021 Water Demand will up by

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Water & Proto-Typology

As explored the influence of water on Canvey Island is undeniable, shaping the form of the island itself. Despite this inherent connection with water & landscape the social interpretation of water on the Island is poor. The seawater surrounding the Island is seen as an enemy, blocked out by a 3 m high sea wall. Proto-typology projects out from Canvey Island into the sea on a naturally forming spit, forming a new connection between the Island and the sea. The industrial

processes within the programme absorb the passing seawater in the estuary; this water is then filtered via forward osmosis to create usable drinking water. The by products of the process form â&#x20AC;&#x2DC;Halitesâ&#x20AC;&#x2122; which crystallise the landscape changing in form and colour relative to their chemical make up. The formation of the Halites allows the sea to slowly dissolve the crystals rationing the influx of salt back into the sea. The industry follows tidal patterns in the water absorption process. / 21

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Visions of Canvey

The collage pictured left is a projected image of what water on canvey could be. The collage is taken from a series of collages projecting vision of water on Canvey Island. Created from research on project 2 systematic elucidation, the programme studies the relationship between water landscape and people of canvey island. The collage aims to illustrate how colour can illustrate things which the eye may not see. The injection of colour into water

provides a natural graph of water content within a reservoir. The aim of the reservoir was to create an environment where the very core of canvey - water was the attraction. Something which goes unnoticed and ignored on a daily basis is brought to the front of our lifeâ&#x20AC;&#x2122;s. This concept is replicated in proto-typology our relationship between industry and recreation is challenged, questioning the overview of our world, sheltered existence. / 23

Industry on Canvey Island

Canvey Island like all places has thrived and diminished along with the timeline of UK industry. Between 1911 and 1951 Canvey Island industry was re-imagined as a hot spot tourist location in the UK. As this industry declined a much more powerful industry came to dominate the landscape of Canvey Island. The petro-chemical industry invested heavily in Canvey Island due to its positioning with oil rigs placed in the North Sea, and also itâ&#x20AC;&#x2122;s connection for London. The town of Canvey Island needed economically reviving and this industry provided the much-needed boost. This heavy industry now dominates the landscape leaving a permanent scar of the Island Scenery. These huge structures create a very intimidating environment thus segregating industry the landscape and the public. These purely functional structures approach industry in an outdated fashion. Proto-typology reforms the industrial typology aiming to create a position where the industry itself is the attraction on Canvey, bridging the gap between people-landscapeindustry. / 24

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Canvey Island Beachscape

Canvey’s connection with the beachscape is undeniable, once the most popular destination in the UK, Londoners flocked to the beaches of the essex coastline in their thousands. Canvey Island became the desirable place to spend your time. As technology developed and the tourism industry changed the once bustling beaches of Canvey Island became distant relics in the memories of the islands residents. After the great flood 1953 the island was surrounded by a 3 metre sea wall. This sea wall signified the closing off of Canvey Island from the beaches surrounding its coastline. “A Heterotropic View” re imagines the way we engage with the beaches of Canvey Island, it asks questions our how and where we spend our time. The aim is to re imagine a heterotopic beachscape of Canvey Island through seemliness integrating the industry that powers the island and the beaches which gave it its character. The new beachscape forms an extension of the landscape encouraging people to exist beyond the sea wall, where a connection between the true nature of our world can be explored integrating the overview effect.

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The Fresh-Water Crisis Water is the most important resource on the planet, is it essential for human life. Despite being surrounding by infinite amounts of water one of the biggest problems facing contemporary society is water shortage. Water shortage not only threatens human life but also has a range of social, cultural and economic issues associated with it. With an ever-increasing population and increase in cities population puts areas under high pressure to provide the correct amount of water. The water shortage problem is further emphasised by increasing climate change, as summers get drier our water resources become depleted. The resultant effect is a two way downward spiral towards the crisis as our current water resources are shrinking year by year and the demand is increasing. This demand for water is expected to increase by 30% in 15 years. The UK has been at the centre of this water crisis with the focus on the Capital, London. Despite the stereotype of British weather London actually receives less rainfall than hot European cities like Rome. London has one of the fastest growing populations coupled with the diminishing resources a problem exists which need to be solved. The answer is taken from the sea, which surrounds us, through the process of desalination. Current desalination processes use reverse osmosis, which requires extremely high pressures to filter the water, these pressure are achieved through burning fossil fuels. The process therefore becomes as contradiction of itself as it solves one issue but exemplifies another. Proto-typology adopts a naturally driven process requiring much less pressure, known as forward osmosis. Proto-typology experiments with different variances within the forward osmosis aiming to exist as a scaleable prototype for solving the London water crisis.

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Desalination

With the looming water crisis one of the obvious solution is to convert the abundance of seawater into fresh drinking water. Current desalination techniques adopt reverse osmosis a technique, which uses high pressure to push fresh water through a semi-permeable membrane. This industry is a contradiction of itself as it is very energy intensive. Proto-typology adopts a forward osmosis process whereby drawn is naturally drawn by polymer hydrogel across a semi-permeable membrane. The process then requires dewatering; here Graphene is experimented with to test variances in solar watering capabilities. The forward osmosis system requires less pressure and therefore can be driven by tidal forces. Proto-typology forward osmosis process improves water influx rates so that a pure mineral based by-product is produced instead of brine (highly concentrated salt water). This byproduct is scattered across the landscape, providing researches with a interesting insight to their success and a attraction for the public. / 31

Beachscape Recreation

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dye added to water will reveal mineral makeup within the crystal, emphasising heterotopia and providing scientists with visual reference of the success of the method.

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Crystallising the Landscape

In reinvented the industrial typology, the programme requires the industry itself to become the attraction. From the influence of project one and two and the text â&#x20AC;&#x153;heterotopiasâ&#x20AC;&#x2122; by Michel Focault a principle heterotropic element is introduced. The current desalination process creates a by-product known as brine. Proto-typology adopts a new method of desalination, which results in a purer by-product being produced. This by-product is a pure form of dehydrated minerals, therefore forms crystals, known as Halites. These crystals vary in form, shape and colour depending on the mineral content. The mineral content of the crystals will change through the varying cycles of the desalination process, reflective of the techniques explored within the desalination plant. As graphene is introduced into the forward osmosis process the efficiency increases and creates a purer mineral. As the crystals are scattered across the landscape they from a key attraction of the project as people come to explore the crystallised landscape of Canvey Island. Furthermore the crystal make up provides scientists with a visual representation of the success of their work relative to the purity and colour of the crystals. The crystals slowly dissolve back into the seawater over a given cycle of the desalination process, therefore rationing the influx of high salt content back into the sea.

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Elements of Proto-typology Proto-typology re-imagines the industry on Canvey Island in a typological and environmental context. Currently as highlighted by the graph all industry is heavily economically driven, the architecture segregates itself from the public. Proto-typology changes this position moving to a public orientated industry, which begins as an exploratory prototype. As the research develops the industry becomes more economically viable. The key elements of the project are outlined above. At the centre of the project is the water crisis which is considered the trigger for the project, public interaction and desalination research dominate the programme, along with the industry becoming a attraction and finding an economically viable solution to the water crisis. / 37

millenium seedbank - stanton williams

Precedents

The explored precedents focus around typology reinvention and the creation of interesting public space. Millennium Seed-bank by Stanton Williams produced a platform by which science and a public museum could co-exist a similar concept is adopted in proto-typology. Happy isles by west 8 is a process of the creation of sand islands off the coast of Rotterdam as a wave break, the process of land accretion through the manipulation of tidal movements is adopted in prototypology. Docking station by Gro architects was a competition entry for the creation of new energy, it suggested a concept of harnessing a tidal river, the approach adopted a system of public spaces extending out into the river which conceal the processes behind. Urban incubator by Chora architects adopts environmentally friendly strategy of creating inner city incubator spaces to create sustainable cities. The rigorous site analysis process will be adopted in proto-typology. Vin by BIG created a public space on a disused area, the quality of the architecture revived the space. / 38

happy isles -west 8

docking station - gro

urban incubator- chora

vin - big architects

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project research water crisis / typology / graphene / forward osmosis / halites / site

developing proto-typology

// 41 41

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The London Water Crisis

Water demand is predicted to rise by 35% over the next 50 years despite resources being further depleted. After two unusually dry winters freshwater supplies for the capital are at an all time low London needs to look towards investing in alternative water resources. The office for National Statistics predicts the population of the UK will rise by 10 million in the next 18 years – reaching 71.4 million by 2030 and 78.4 million by 2050. Coupled with this climate change projections for the UK also suggest by the 2050’s summer temperature will increase and rainfall will decrease significantly. Despite London’s reputation it already receives less rainfall than cities like Rome. Nicola Poole, manager for water resources access and allocation at the agency, says climate change projections, which indicate the temperature may rise by 1.3C to 4.6C across southern England by 2050, would lead to an 80% decrease in summer run-off water - gather-able rainfall – available. It would also leave half of the river basins across England and Wales deficient during the summer months. Analysts say there is no short-term concern but long term planning is required. / 43

Soft Matter

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Cite this: Soft Matter, 2011, 7, 10048

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Dan Li,a Xinyi Zhang,a Jianfeng Yao,a Yao Zeng,a George P. Simonb and Huanting Wang*a Received 5th June 2011, Accepted 30th August 2011 DOI: 10.1039/c1sm06043k We report here on new composite polymer hydrogel particles with light-absorbing carbon particles incorporated within them that can be used as draw agents in the forward osmosis process of desalination. These hydrogels are synthesized by free-radical polymerization of different monomers (e.g. sodium acrylate, N-isopropylacrylamide or their mixtures) and the crosslinker N,N0 methylenebisacrylamide with light-absorbing carbon particles. We have previously shown that hydrogel particles are able to draw pure water through forward osmosis membranes, and then the water can be removed by pressure or heating, or a mixture of both. The incorporation of light-absorbing particles leads to natural, enhanced heating and dewatering of the composites compared to neat hydrogels during such irradiation with light. However, it is also advantageously found that these composite polymer hydrogels exhibit higher swelling ratios, and thus produce higher water fluxes in the FO process. Furthermore, with the increasing loadings of carbon particles, the water recovery rates from the swollen composite hydrogels are found to be greatly enhanced.

Introduction Forward osmosis (FO) is a process in which osmotic pressure difference serves as the driving force for water transport and a semipermeable membrane acts as a separation medium. This spontaneous process has great potential to achieve energy-efficient separations in many areas, such as the desalination of seawater, brackish water or purification of contaminated water sources.1 In the FO process, the concentrated solution on the one side of the membrane is the source of driving force, which is normally called the draw solution, draw (osmotic) agent, or driving solution.1 The main criterion for selecting a suitable draw agent is that it has a higher osmotic pressure than that arising from the feed solution, in order that pure water is drawn through the barrier to the downstream side. Furthermore, in the FO

a Department of Chemical Engineering, Monash University, Clayton, Victoria, 3800, Australia. E-mail: huanting.wang@monash.edu; Tel: +61 3 9908 3449 b Department of Materials Engineering, Monash University, Clayton, Victoria, 3800, Australia † Electronic Supplementary Information (ESI) available: FT-IR spectrum of sucrose. SEM images of C–S carbon fillers, and composite hydrogels with different loadings and sizes of carbon particles. FT-IR spectra of pure and composite polymer hydrogels. TGA results of carbon particles (C–L and C–S). Optical microscopy images of composite hydrogels with different loadings and sizes of carbon particles. Water recovery rates of composite hydrogels with the addition of different sizes of carbon fillers (C–L and C–S) after the exposure to sunlight with a radiation intensity of 1.0 kW m�2. Determination of the ratio of liquid/vapor water, and the purity of water produced in the dewatering process, and recycle experiments. See DOI: 10.1039/c1sm06043k/

10048 | Soft Matter, 2011, 7, 10048–10056

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process it is necessary to consider an effective method for the recovery of water and draw agents after FO process, and preferably reuse the draw agents. So far, various chemicals have been tested as draw agents, such as sodium chloride, glucose or fructose, ammonium salt solute, etc.1–6 However, based on the use of these materials to date, there remains a need for developing new draw agents; which should meet the following requirements: low energy consumption for regeneration; complete separation from the fresh water product; low or no toxicity; and chemically nonreactive with polymeric membranes.1 Superabsorbent hydrogels, which are formed of loosely hydrophilic cross-linked polymers, have the capacity to undergo a drastic change in volume by absorbing and retaining several hundred times of their own weight of water while still remaining insoluble.7 This superior property arises from the flexibility and hydrophilicity of the polymer network, depending on the chemical composition of hydrogels.8,9 The presence and dissociation of ionic species within polymer hydrogels induce the hydrogels to swell even more and develop a higher internal ion osmotic pressure. Furthermore, these cross-linked polymer networks are capable of reversible volume change in response to external stimuli, such as pH, temperature, electric field and solvent composition. For example, as a standard temperaturesensitive polymer, poly(N-isopropylacrylamide) three-dimensional polymer hydrogel exhibits an unique characteristic; when heating close to or above 32 � C, it undergoes a reversible lower critical solution temperature (LCST) phase transition from a swollen hydrated state to a shrunken dehydrated state, expelling the majority of water.10–12 These superabsorbents have attracted unwavering attention and found extensive application This journal is ª The Royal Society of Chemistry 2011

Cite this: RSC Advances, 2013, 3, 887

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Composite polymer hydrogels as draw agents in forward osmosis and solar dewatering†

Significantly enhanced water flux in forward osmosis desalination with polymer-graphene composite hydrogels as a draw agent3 Yao Zeng,a Ling Qiu,b Kun Wang,a Jianfeng Yao,*a Dan Li,b George P. Simon,b Rong Wangc and Huanting Wang*a We report here a new strategy to dramatically increase water flux in a forward osmosis (FO) process using reduced graphene oxide (rGO)-composite hydrogels as draw agents as well as increasing the rate of the subsequent regain of pure water from the hydrogel particles. The composite hydrogels were prepared by incorporating 0.3 wt%–3 wt% rGO into two different hydrogels: poly(sodium acrylate) (PSA) and poly(sodium acrylate)-poly(N-isopropylacrylamide) (PSA-NIPAM). The amount of incorporated rGO sheets had a significant effect on the swelling pressure of the composite hydrogels and the composite hydrogels with contained small amounts of rGO sheets (0.3–1.2 wt%) showed significantly enhanced swelling ratios while those with more rGO (e.g., 3 wt%) exhibited decreased swelling ratios. Consequently, significant enhancements in water flux in the FO process were achieved for composite hydrogels with small amounts of rGO. When compared with the pure hydrogels, the composite hydrogels PSA-1.2 wt% rGO and PSANIPAM-1.2 wt% rGO showed increased water fluxes of some 310% and 227%, respectively, when 2000 ppm of a NaCl aqueous solution was used as the feed. When deionized water was used, even higher water fluxes were attained, i.e., 8.2 L m22 h21 for PSA-1.2 wt% rGO and 6.8 L m22 h21 for PSA-NIPAM-1.2 wt% rGO. The swelling process of the particles was investigated using optical microscopy where it was found that the addition of small amounts of rGO greatly increased the softness of the composite hydrogels and improved the inter-particle and particle-membrane contact, leading to dramatically improved water fluxes.

Received 10th July 2012, Accepted 11th November 2012

In addition, the light-absorbing property of rGO produced much better outcomes in terms of dewatering of the composite hydrogels in the second stage of the FO process, in which the pure water from the

DOI: 10.1039/c2ra22173j

hydrogels is harvested, with dewatering stimulated by heating induced from absorbed solar energy. The water recovery rate for composites with 1.2 wt% rGO was found to be twice as fast as that for pure

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hydrogels.

Introduction Forward osmosis (FO) desalination is an emerging technology for the more energy-efficient production of fresh water from seawater and other water sources and wastewater reclamation. In the FO desalination process, water is withdrawn from saline water through a semi-permeable membrane by a draw agent (solute) that possesses a higher osmotic pressure than the feed solution. Pure water is subsequently harvested from the draw solution by a range of stimuli, such as the application of heat, a

Department of Chemical Engineering, Monash University, Clayton, Victoria 3800, Australia. E-mail: jianfeng.yao@monash.edu; huanting.wang@monash.edu; Tel: +61 3 9905 3449 Department of Materials Engineering, Monash University, Clayton, Victoria 3800, Australia c School of Civil & Environmental Engineering, Nanyang Technological University, Singapore 639798, Singapore 3 Electronic supplementary information (ESI) available. See DOI: 10.1039/ C2RA22173J b

This journal is The Royal Society of Chemistry 2013

depending on the nature of the draw agent. By taking advantage of this naturally-driven osmotic flow, FO desalination has shown great potential to reduce energy consumption in desalination processes. However, some major issues associated with membrane performance (such as internal concentration polarization) and energy-efficient recovery of the draw agent need to be addressed to promote commercial implementation of FO desalination processes. 1–3 In recent years, significant research effort has been directed to tailoring the microstructure and chemistry of FO membranes to improve water flux, reduce internal concentration polarization4–8 and explore new draw agents to improve the energy efficiency and purity of the product water.9–13 Among the many draw agents investigated so far, ammonium bicarbonate has been considered as a promising draw agent for practical FO desalination applications since it has a high osmotic pressure, can be separated from water as ammonia and CO2 by low temperature distillation and recycled by

RSC Adv., 2013, 3, 887–894 | 887

w a t e r r e s e a r c h 4 7 ( 2 0 1 3 ) 2 0 9 e2 1 5

Desalination 287 (2012) 78–81

Available online at www.sciencedirect.com

Contents lists available at ScienceDirect

Desalination j o u r n a l h o m e p a g e : w w w. e l s ev i e r. c o m / l o c a t e / d e s a l journal homepage: www.elsevier.com/locate/watres

Forward osmosis desalination using polymer hydrogels as a draw agent: Influence of draw agent, feed solution and membrane on process performance Dan Li

a,c

Forward osmosis processes: Yesterday, today and tomorrow Tai-Shung Chung a,b,⁎, Sui Zhang b, Kai Yu Wang a, Jincai Su a, Ming Ming Ling a a b

Department of Chemical and Biomolecular Engineering, National University of Singapore, 119260 Singapore NUS Graduate School for Integrative Science and Engineering, National University of Singapore, 117576 Singapore

, Xinyi Zhang , George P. Simon , Huanting Wang *

a r t i c l e

i n f o

a b s t r a c t

Department of Chemical Engineering, Monash University, Wellington Rd, Clayton, VIC 3800, Australia Department of Materials Engineering, Monash University, Wellington Rd, Clayton, VIC 3800, Australia c Environmental Engineering, School of Environmental Science, Murdoch University, South St, Murdoch, WA 6150, Australia b

article info

abstract

Article history:

We have previously reported the use of hydrogel particles as the draw agent for forward

Received 14 August 2012

osmosis desalination. In the present work, the effects of draw agent, feed concentration

Received in revised form

and membrane on the process performance were systematically examined. Our results

23 September 2012

showed that the incorporation of carbon filler particles in polymer hydrogels led to

Accepted 25 September 2012 Available online 3 October 2012

The purpose of this short communication is to share our perspectives on future R & D for FO processes in order to develop effective and sustainable technologies for water, energy and pharmaceutical production. © 2010 Elsevier B.V. All rights reserved.

Keywords: Forward osmosis Osmotic power Desalination Osmotic membrane bioreactor Energy and water

enhanced swelling ratios of the draw agents and thus higher water fluxes in the FO process. The composite polymer hydrogel particles of sizes ranging from 100 mm to 200 mm as draw agents induced greater water fluxes in FO desalination as compared with those

Keywords:

with larger particle sizes (500e700 mm). Similar to other types of draw solutes, as the salt

Forward osmosis desalination

concentration in the feed increased, the water flux created by the polymer hydrogel draw

Draw solute

agent decreased; the use of a cellulose triacetate forward osmosis membrane resulted in

Polymer hydrogel

higher water flux compared with the use of a polyamide composite reverse osmosis

Stimuli response

Article history: Received 8 August 2010 Received in revised form 8 December 2010 Accepted 8 December 2010 Available online 11 January 2011

Introduction

Forward osmosis (FO) is the membrane separation process in which the osmotic pressure difference serves as the driving force for water transport, with a semi-permeable membrane acting as a separation medium (Li et al., 2011b,c). In a typical FO separation, the feed solution, i.e. saline water, passes through one side of a semipermeable membrane, and a draw agent of high osmotic pressure (compared to that of saline water) flows on the other side of the membrane. Due to the naturally driven osmotic flow, water permeates through the membrane from the feed solution to the draw agent side (Cath et al., 2006; Li et al., 2011b,c). After FO process, it is necessary to separate the water and draw agent for the recovery of pure

water product and regeneration of draw agent for reuse in the FO process. To date, FO desalination has shown a number of potential advantages, such as reduced fouling propensity, easy cleaning, low cost and so on (Zhao et al., 2012). In particular, when compared to the hydraulic pressure-driven membrane process reverse osmosis, the FO process does not require a high feed water pressure, thus demonstrating great potential to reduce energy consumption in desalination processes toward the thermodynamic minimum (Cath et al., 2006). A suitable draw agent is essential for successful operation of the FO process, and there are several criteria defined for selecting a draw agent (Cath et al., 2006; Zhao et al., 2012). Firstly, draw agents should possess a high osmotic pressure,

* Corresponding author. Tel.: þ61 3 9905 3449. E-mail address: huanting.wang@monash.edu (H. Wang). 0043-1354/$ e see front matter ª 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.watres.2012.09.049

1. Introduction Clean water, renewable energy, and affordable healthcare are three major concerns globally due to water scarcity, resource depletion, and high medical cost. Forward osmosis (FO) is one of the unique and emerging technologies that can produce both clean energy and water driven by the osmotic pressure difference across a semi-permeable membrane. FO can also be used for controlled drug release and dehydration of pharmaceuticals during syntheses. However, so far most FO membrane studies have been focused solely on either energy or water production. For example, the ﬁrst osmotic power plant developed by Statkraft (Norway) in 2009 is a typical example of geophysical ﬂuxes derived from the mixing of freshwater and seawater [1]. The mixing is spontaneously driven by the salinity gradient between seawater and fresh water across a semi-permeable membrane that retains ions but allows water to diffuse through. Therefore, this is an environmentally friendly industrial system without chemical discharging. Due to record high oil prices, FO based desalination has recently received worldwide attention [2,3] because it operates without high pressures and high temperatures. Compared to traditional pressure-driven membrane processes [4], FO offers recognized advantages including high rejections to contaminants, low membrane fouling and potentially less operation energy. Therefore, FO membranes have great potential to replace ultra-

⁎ Corresponding author. Department of Chemical and Biomolecular Engineering, National University of Singapore, 119260 Singapore. Tel.: +65 65166645; fax: +65 67791936. E-mail address: chencts@nus.edu.sg (T.-S. Chung).

filtration (UF) membranes currently used in membrane bioreactor (MBR) for water reuse [5,6]. Syntheses of pharmaceuticals are often carried out through multistep syntheses, separations and purifications to concentrate small molecular weight pharmaceuticals and intermediates [7,8]. Since pharmaceutical products are labile and heat sensitive, athermal separation processes are preferred. Current extraction technologies for pharmaceutical syntheses not only consume a large quantity of solvents and space, but also create problems of waste solvents. Using FO technologies to dehydrate and concentrate pharmaceuticals may solve some of these problems. Several reports have estimated the annual market value of FO membranes for osmotic energy, water reuse, desalination, and others will be significantly larger than the combination of the present RO and UF markets [9–11]. The purpose of this short communication is to share our perspectives on future R & D for FO processes in order to develop effective and sustainable technologies for water and energy production and pharmaceutical dehydration. They can be summarized as follows: 2. Integrated FO processes for energy and water production Reverse osmosis (RO) is currently the dominant desalination technology. However, in addition to the fouling problem, the perspective of high oil prices has hindered its future potential because RO uses extremely high hydraulic pressures (i.e., energy and cost) to run the process. Compared to RO, FO offers advantages including low operation pressure and temperature, potentially low fouling and less energy consumption. When integrating FO with osmotic MBR and osmotic power generator, the seawater desalination may become an

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A Graphene Industry Graphene is a revolutionary material discovered at the university of Manchester in 2010, it is the world first 2d material and its extraordinary properties promise rapid advances in technology and industry. Graphene was described as the future material of our world and subsequently Professor Andre Geim was awarded the Noble prize for this discover. Graphene has been proven by scientific research to rapidly change the desalination process. In the forward osmosis process graphene is able to substitute large amounts of energy required for dewatering, using heat. A forward osmosis draw agent of hydrogels absorb the fresh water molecules as they expand through a membrane, the malleable nature of graphene aids significantly compared to existing methods, whilst its molecular construction completely blocks salt minerals from entering the draw agent. Most importantly however graphene extremely powerful conductive properties allow it to absorb energy 300x time for effectively than existing draw agents. This significant advance means that the previously wasteful process of dewatering via heating can now be substituted by solar dewatering to remove the freshwater from hydrogel draw agent. Currently these processes exist successfully in a lab environment but further larger scale research is required, spawning proto-typology. / 48

molecular make up of graphene

world strongest material

bendable

harder than diamond increase desalination effiecency by 300%

transparent

world most solar conductive material

editable on a molecular level

300 x stronger than steel

world first 2d material

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forward osmosis diagram

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Desalination - Forward Osmosis Scientific advancements have led to the creation of super materials like graphene. The introduction of these super materials encourages scientists to look at new way in our industry processes. The properties of graphene have led to a series of scientific investigations into its use in the desalination process. One of the foremost of these studies is its integration into the forward osmosis process. The introduction of graphene improves the membranes filters permeability, but more notably has two other properties essential to the process. The integration of graphene into the draw agent in the osmotic process induces water at a better water flux rate and the conductive properties of graphene allow for the first time solar watering to occur to remove the freshwater from the draw agent. The process outlined to the left, highlights each stage of the forward osmosis process, driven by the tides sea water is pushed up into the desalination plant, from here the freshwater molecules are drawn through the semi-permeable membrane via osmosis. The draw agent simulates a different osmotic pressure to the seawater side of the membrane thus drawing the freshwater across. The polymer hydrogels (draw agent) expand with the influx of these freshwater molecules. The freshwater is then trapped within the draw agent, as the osmotic level is equaled. At this point solar dewatering begins where the polymer hydrogels are exposed to sunlight; the ultra conductive properties of graphene allow the release of the freshwater molecules as the hydrogels gain energy. The final result is the purest possible freshwater. Left behind is the accumulation of salt minerals not absorbed by the draw agent, these crystallize the landscape changing in form and colour relative to their mineral content.

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Halites - Crystallised Landscape

A major of element of the architecture is the re-invention of industry as an attraction. Influenced by the concept of Hetertopias an industrial by product is transformed into a visual attraction for Canvey Island. The new method of desalination explored creates a pure by product, as the freshwater is extracted from the saltwater at a molecular level. Pure salt minerals remain which then will crystallize the landscape as it is left exposed to the natural forces. The crystals will form following the timeline of the desalination plant, the form and colour of them is further dictated via the processes within the plant. The crystals will act as a direct representation of the success of the desalination process to the scientists and the public indicated by their colour, form and purity. The molecular process of extracting the fresh water causes disfigurement within the crystal structure, which will directly correspond to the amount of graphene used in the process. Therefore as the prototype desalination plants improve its methods over time the quality of the crystals improve as they become purer in mineral content. / 52

in reality the crystals are colorless; it is the disfigurement of the crystal lattice structure that bends and reflects light and particles to create the illusion of colour.

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Halite formation experiments Conceptual ideas of form are explored with the creation of halites crystals patterns. For this process water was desalinated using a traditional heating solution leaving behind a crystalline resin similar to what would be left on the Forward Osmosis membranes. The resin was then shattered on black mount-board. The evolution of the crystals is documented as the resin crystallites forming distinct linear patterns. The patterns shown at the bottom are zoom in of the overall structure, the resin itself flowed around the mount-board like lava following the small intricacies in the levels of the mount-board. The dencity of the crystal resin at each stage determined how it looks when crystallised. For example thicker resin molded into larger linear patterns overlaid on top of eachother. In contrast small thinner section of the crystals form distinct moments and almost 3d like forms. The experiments were then traced and ideas of form are placed into the building. The relationship between density and thickness or the visual is explored a illustrated by the photographs shown left.

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HIGH TIDE

LOW TIDE

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Tidal Patterns

Tidal patterns hold a very significant influence in the project, they influence both the desalination process and key recreational spaces. Salt water is absorbed into the prototype at periods of high receding tide, a process occurring daily. The membranes in the process go through this cycle of submergence and emergence creating atmosphere and variations in form. This cyclic principle is further reflected in the recreational beachscape created by the membrane filters. Here the atmosphere is shaped by the tides along with the spatial configuration, as the tide moves in and out creating and dissolving space. The tidal data explored here is taken from South-End Marina predicted tide table for 2013 less than a mile away from my site at Canvey Point. The graph marks out the diurnal cycles of the tides. The diurnal cycle is based on a lunar cycle between new-half-full moon, this cycle on average takes around 14 days. The peaks marked on the high tide line by the red dots are known as spring tide whilst those marked on the low tide line are neap tides. The data illustrates the high tidal variance of the site. My site is located at a shallower section than that of Southend therefore the sea level height starts at +1m above sea level which is calculated from the LAT (lowest astronomical tide). This tidal range means that throughout the year at periods of low tide land will be exposed. Key tidal information which heavily influences the design is outlined below. Highest Spring Tide- 21/08/2013 = 5.9m Highest Neap Tide- 19/03/13 = 1.5 m Average High Tide - 245m / 45 = 5.4 m Average Low Tide - 39.4/45 = 0.8m

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Site Introduction

Sited at Canvey Point proto-typology sits at the mouth of the Thames estuary. This tidal estuary goes through a number of patterns everyday. These tidal movements and flow of water determine where the project site has been placed. A marks Canvey Point spit, here the analysis of rock deposition has been used to gauge where a slow clear flow of water can pass through the project. The dotted line mark the angle between the current sediment deposition where a clear flow of water will exist. The aspect is then rotated to optimiseâ&#x20AC;&#x2122;s a south facing aspect for the solar de-watering process. The tidal flow into the space is then utilised for water absorption within the forward osmosis membranes. The remaining spaces outside this zone aims to integrate the existing spit landforms into recreational spaces creating a new beachscape for Canvey Island. The site of A bolts directly into existing water and electricity infrastructure on the island, as a pump house and sub station is located at the plus anchor point. The beachscape concept is extended from existing Canvey promenade, the aim is to draw people from behind to seawall to engage with a future landscape which is designed to provide the overview effect signifying a cognitive change in the way we look at industry and leisure the driving forces behind our world.

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approach.instruction programme timeline / relationship collage / site programming / design elements / room book

proto-typology programming

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Site Overview The aerial image below highlights the key features of the site along with photographs of interesting elements. Lookout at Canvey Point

Canvey Island Yacht Club

East Industrial Area

Canvey High Street Recreational Space Behind Sea-wall

Site Infrastructure Pump Station Series of Abandoned beaches The Coastal Promenade Road General Water Pumping Station Tidal Sand Deposits

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Site Programming The below panoramic highlights the key programming elements of the project. Further detail is followed at on the next page.

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Tidal Flow - Receding Tide

Site Programming The complex system of the desalination prototype requires very detailed site programming approach. The initial positioning of the site sits between a large gap in the naturally forming spit. Coastal analysis of this gap illustrates a smooth flow of water with minimal sediment deposition. Marked as [A], the prototype / 66

will be able to absorb the tidal waters and form the new beaches of Canvey Island. Timing is essential in the desalination process. Water is absorbed into the system during receding tide periods where the salt content will be lower than in an oncoming tide. The form of the site therefore is positioned in a direction

which can channel receding tides into the filters and disperse oncoming tides around the system. The concept is illustrated in the tidal maps to the right with the main form axis marked by the dashed line. [A] the panoramic photo below highlights more levels of site programming. Most notable of

these issues is the extension of the promenade axis cutting the boundary between the sea wall and the enclosed Canvey Landscape. This aims to link the public, industry and the beachcape in a newly imagined site.

Tidal Flow - Oncoming tide

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Solar Exposure The solar de-watering process is based on existing solar panel technology, estimating a 85% efficiency rate of de-watering throughout the UK based on the panel being on a south facing aspect and current solar exposure data.

Sunrise Time

Azimuth Angle

Sunset Time

Azimuth Angle

Spring Equinox March - 20th