SMALL SCALE WOOD COGENERATION IN THE DELTA REGION OF BUENOS AIRES ARGENTINA
Odobez Norberto S. – Torres José Luis – García Ebbens Carlos A. Technological National University – Regional Delta Faculty San Martín 1171 – Campana (2804) – Buenos Aires – Argentina TE.: 0054-3489-420400 Int. 111- E-mail: odobezn@frd.utn.edu.ar
This is the presentation of the first part of our project. Which shows the potential recourses that have the forestry sector in the region, for using as energy vector TECHNICAL SUMMARY THE COMPLETE PROJECT First par • We will carry out a detailed analysis the residues of a forest harvest in islands of Delta of Parana River. The different residues of woody characteristics will be classified. • • The woody surpluses will be quantified both the forest harvest as and pruning in plantations of willows and poplars. • The form of manipulation will be studied, loads and transport up to the place of treatment of woody residues to be use as fuel. Second part The heating power of the woody residues will be measured in different times of the year. • • Collection of the woody residues and its preparation will be transformed into gas. • An equipment to generate gas from woody residues will be designed and developed. • The generated gas will be used to stimulate an engine of internal combustion to which an electrical generator. (Small energetic decentralised generator). The engine and the generator are of national manufacture in series, which will have to be adapted for its functioning. This system will have a power of generation of approximately 3kVA to 5kVA in the research beginning, what means a capacity of nourishment with electric power that will allow to satisfy demands in isolated zones, turning the technological transference into a small energetic decentralised mobile generator. An environmental analysis of emission of carbon, product of the burning of woody material for the gas production will also be carried out. The woody material will be chosen of two or more samples extracted from a hectare of poplars and willows that turn out to be representative of the Delta surfaces forestry. 1.- General considerations 1.1.- Weather It is possible to consider the climate of the Delta region as moderate (tepid). The warmest month (January) gives an average of temperature of 22,4ºC and the freshest month (July) of 9ºC. The rainfall, approximately 960 mm per year, is distributed uniformly enough among the months, but the number of rainy days is limited since most of the rainfall takes place during intense downpours. The average of fogginess is low and the solar light is abundant. Due to the proximity to the Atlantic Ocean and the Rio de la Plata and of the great number of rivers and marshes in the same Delta, the relative dampness is raised on all the stations of the year and gives an average of approximately 75 %. The winds are generally light.
2.-Description of the place of the extraction of the material of this study in particular and of the plantations in general 2.1 Location of the place of the evaluation The activity was centred on the establishment the OASIS of the company SAVITAR, placed in Islam’s zone of Campana district, on the Route 12, Km 103 between the bridges of the rivers Parana de las Palmas and Parana Guazu. This establishment was chosen for its accessible location by firm land, for typical conditions as for the forest production, the establishments of the zone and for especially the attitude of the personnel of the company to a research of this type. The fields were flooded because of being in a closed dock, that received more than 400mm of rain during the
months of October and November of the 2001, due to this fact the establishment stopped the tasks of or normal forest harvests. Because of this reason they walked a long 7000Ha. with crop determining the average places, planted with American Willow (babilonica Salix CV sacramenta), that turns out to be the predominant clone in the zone.
of the same clone of nonflooded zones were analysed, choosing the average. The collection of all the material that was in the ground was made, being taken and transported for its later natural drying and its evaluation, and besides the material adhered to the ground, not harvested in the forest harvest. Was also measured.
2.2 Forestry system After the drainage were caused the grounds become fields with high tenor of useful humid organic matter, which confers much fertility to them and it makes them specially apt for the forest cultivation based on tolerant species to conditions of excessive humidity, as the salicaceas are. Diverse clones of willows stand are located in the lowest places and the poplars are located in albardones. As the Delta is subjected to periodic floods caused by the high tides of the Rio de la Plata and by the high tides of the rivers Uruguay and Parana, in certain circumstances and in zones affected by the crescents perimetrales docks are constructed, that according to their profile can be denominated little dock when they simply do not pass the 1.5 m of height, or docks when they are of greater spread. But the most interesting forestry fundamentation for the producer when he constructs docks, is that it allows him to increase significantly the areas destined to the cultivation of land poplars in areas of transition between low and high.
The different observations and quantification of the logging residues, showed the following considerations and data: Fine branches Heavy Branches Stumps topped of the ground Pieces with the wrong shape (twisted stems) Pieces rotten or pasmados Hooks or pieces with branches that affect the cylindrical form of the piece Forks and Stumps adhered to the ground Therefore the remainder material never is uniform due to: a) turns or harvests, since the salicaseas sprout again and the same foot is used during 5 turns and sometimes more. b) type of clone or variety c) type of ecological zone of plantation d) type of conduction of the forestry The amounts obtained in the average parcel, can be classified according to their type and size in the following way:
3.- Harvesting Methods It is the total harvest or tree felling at ground level at the time of maturity or turn of cutting of the different forest species 4. - Present production and its classification according to their use The cellulose industry is the one that requires the most of the raw material, then they follow the wood for sawed and agglomerated industry. The marketing of forest products has as an objective supply the internal market especially. 5.- Probable use of the logging residue not used at present and its energetic relation as biomass 5.1.-Methodology of Analysis. For the evaluation of the logging residue which stay in the land, after the forest harvest, parcels of 2m x12m were marked at random since the cultivation are 2mx3m out of an original afforestation carried out in 1969 and that has been harvested 3 times since the salicaceas have the particularity of sprouting again. Other parcels
Type of Material Pasmada Fine Branches Branches diameter average 1” Branches diameter average 11/2” Branches diameter average 2 ½” Branches diameter average 3” Cut Stump (it frees) Stump adhered to ground (2 Stocks) Total
Amount (kg) 3,3 1,08 4.34 3.69 6.75 9.30 6.48 34.00 63.50 132.44
The weighing was made soon after of 20days airing since part of the material was extracted from a totally flooded field. The total of the considered material obtained as remainder is of 132,44Kg The material by hectare would be: 24m2- 132.44 Kg/10000m2 = 55138Kg = 55tn/ha
In order to make an ample classification of the products we can say that.
Size
Tons / hectare
Percentage of the total (%) 11.96 14.40
Small Medium
6.58 7.92
Big
40.50
73.64
TOTAL
55.00
100
Observations Branches and stems below 7,5cm diameter Hooks or stumps that are taken from the main (pulp wood-logs) and are free from the ground, and amazed Stumps that are adhered to the ground, not extracted by its wrong shape, in the forest harvest.
The last harvest gave an approximately quantity of 205tn/ha staying as woody residues 55tn/ha, which give as a total 27%. 5.2 Determination of humid percentage of logging residue Sample 1 2 3 4
Initial weigh (grs) 205,03 204,21 581,45 83,74
Final weigh
Difference
183,25 183,17 481 75,49
21,78 21,04 100,45 8,25
As we can observe the values of humidity found are within the suitable parameters to be able to be used in a gasification system. 5.3-Steps of the normal process of forest harvest for the production of raw material to the manufacture of paper 1 2 3 4 5 6 7 8
Tractor Light truck Previous cleaning of the plantation Survey, cutting of branches and logs of trees Piling up of pieces and the branches and other waste Loaded on trailer in Positioning of the rail field decauville and loading of light truck. Taking out from the By light truck forest by tractor and trailer Transferring to truck Unloaded and piled up on ways, for trucks Loaded to final transport when the transfer was done Freight to factory (approximate 100kilometros)
5.4-Composicion of the costs of the wood of salicaceas for manufacturing of paper. Standing plantation Processing (of point 1 to 7) Final Load Administrative and management expenses TOTAL
14$/t 13$/t 9$/t 6$/t 42$/t
5.5-Costs of the obtaining of the ligneous material to be used likes fuel
Humid percentage (%) 10,62 10,30 17,27 9,85
The ligneous by-product of the forest will be extracted after of the main material extraction, for that they will be used the same extraction mechanisms, such as decauville rail or tractors with trailers, adapted to contain non pile ligneous material, the trailer container will remove it in pile form. Tractor 1) Piled up and accommodated of branches with greater rigor and reviewed of high stumps 2) Taking out from the forest 3) Transfer to truckable way if it were necessary 4) Charge to final transport if it were necessary 5) Final transport (approx. 15Km) 6) Administrative expenses 20% of previous TOTAL
5$/t 3$/t
Light truck 5$/t 3$/t 1.5$/t 1.5$/t
2$/t 1.7$/t
2$/t 2.2$/t
11.7$/t 15.2$/t
6.-Comparison of the situation of the consumption of fuels for the domestic generators and of microenterprises (PYME) According to previous studies a classification of the necessities of the electrical consumption that are required in the insular sector can be done, according to the following scheme: 1) From 3kVA to 5kVA for simple house or health centre 2) From 5kVA to 10kVA for familiar using with some activity of microenterprises. pg. (fish storing) 3) From 10kVA to 30kVA for groups of families with some activity PYME using / rural School 4) From 30kVA to 150kVA for enterprises PYME using. pg. (sawed)
Taking as example the case from the establishment, this account at the moment with two very next houses in the administration zone of and a space where they make other productive processes. The provision of Electrical Energy is made for the house with an equipment of 5kVA fed with GLP, the other equipment of 30kVA fed with diesel oil that works 10hs per day of Monday to Saturday and another movable equipment of reserve with a 90kVA power. Given the structure of previous consumption, we could classify the establishment within 1) and 4). The costs of the fuel for both equipment are such of seat in zone of the continent. They are considered in: 0,23$/litre for GLP and of 0,6$/litre for the Diesel oil. Ref: February 2002; 1U$=2,2$
data of the operator of 4lts/h and working (not to total load aprox. 55%) 10hs/day, this implies an annual fuel cost of: 7200$/year, if the equipment worked to total load during the same time, the annual fuel cost will be of : 12440$/year. For the case of a gasification system that consumes 2kg/kW.h of firewood to a fuel cost of 15$/tn, for the same maxim power, this it would give an annual cost us: 2592$/year. It is due to clarify that it has not included in any case the amortisation costs, the maintenance of the producing and generating equipment. In this case it is single to have an initial comparative value of the potentiality of the use of this resource in replace of the fossil fuel.
Doing a comparison of costs with the present generator of 30kVA we can say that: Consumption according to Case
Installed Power
Quantity of Size of Annual Consumpti Firewood Working to Daily the Consump Consump firewood on of the material tion firewood maximum tion Ref.:55tn/ha from power gasification Kg/kWe Kg/h hs/day kg/day Tn/year ha/year
Nº
KW
1
3a5
2
10
6
60
2
5 a 10
2
20
10
3
10 a 30
2
60
15
4
30 a 150
2
300
15
We can come following considerations a)
b) c)
d)
It makes reference to a consumption of the gasification system of 2kg/kwe, superior to the average of the equipment which are at the moment used in others countries. Is considered that the equipment works to maxim power For caseNº1 will be for the one of a family type of the Delta, its annual resource would be satisfied with an annual harvesting of 3.2ha. of small material. For the CaseNº4, in which are considered all types of material, is due to add to the final costs the referring ones to chipping of the wood.
7.- Reference 1.-Garcia C.- Odobez N. ;1999. Estrategias de Desarrollo Sustentable para un Microemprendimiento
small
Adjusted according to the obtained percentage ha/year
21
0,4
3,2
200
70
1,3
small
10,6
900
315
5,7
21,7
4500
1575
28,7
small/ medium small/ medium/ big
28,7
en Zona Aisladas del Delta Bonaerense; FONCAP-OEI; Buenos Aires. 2.-Garcia C.- Torres J.L.- Odobez N.; 2000. Estrategias de Desarrollo Sustentable en Humedales del Delta Argentino; 1ra. Conferencia Mundial Sobre Biomasa para Energía e Industria; Sevilla, España; Vol II,188 p 3.-FAO, 1997. Reunión Regional sobre Biomasa para Producción de Energía y Alimentos; Cuba. 4.-FAO,1994.Universidad Nacional de Honduras; Seminario Regional sobre los Sistemas Dendroenergeticos Optimizados, para el Desarrollo Rural y la Protección Ambiental; Memorias 5.-Encuentro sobre Gasificación de Biomasa, 1999 IDAE, Madrid, Libro de Ponencias 6.-Reunión Regional sobre Generación de Electricidad a partir de Biomasa. FAO Serie ForestalNº7, 1995, Memoria 7.-Producer-Gas technology for Rural Aplications, 1985,FAO,Nº61