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IMPLEMENTATION OF LOW COST TECHNOLOGY FOR BIOGAS GENERATION FROM KITCHEN WASTES: AN ALTERNATIVE SOURCE OF RENEWABLE ENERGY INVESTIGATORSDr. Solomon Libsu (Department Chemistry, College of Science, Bahir Dar University) Prof. R B Chavan (IoTex, Bahir Dar University)Dr. Ayalew Wonde (Department of Biology, College of Science, Bahir Dar University) BAHIR DAR UNIVERSITY, BAHIR DAR, ETHIOPIA.
IMPLEMENTATION OF LOW COST TECHNOLOGY FOR BIOGAS GENERATION FROM KITCHEN WASTES: AN ALTERNATIVE SOURCE OF RENEWABLEContentsProject summaryAbstract1. Introduction 1.1 Environmental issues 1.2 Health issues 1.3 Alternatives 1.4 What is biogas? 1.5 Benefits of biogas 1.6 Substrates used for anaerobic digestion 1.7 Biogas content of different substrates 1.8 Biogas digester technologies 1.9 Biogas program in few developing countries 1.10 Biogas for better life: An African initiative2. Problem statement3 Objectives4. Method and Design5. Project time schedule6. Project budget7. References
PROJECT SUMMARYProject title Implementation of low cost technology for biogas generation from kitchen wastes : an alternative source of renewable energyNature of project Research project of national importanceInvestigators Dr. Solomon Libsu (Department Chemistry, College of Science, Bahir Dar University) Prof. R B Chavan (Institute of Technology for Textile, Garment and Fashion Design, Iotex, Bahir Dar University) Dr. Ayalew Wonde (Department of Biology, College of Science, Bahir Dar UniversityProject duration 18 monthsResearch staff OnerequirementFinancial ETB 65,000requirementContact details Prof. R. B. Chavan Dr. Solomon Libsu Dept. of Chemistry, Bahir Dar University, Bahir Dar Phone Office : Mobile: 0918231147 E mail: Dr. Ayalew Wonde
ABSTRACTAbout 85-90% of the Ethiopian population lives in the rural parts of the country. This segment ofthe population is totally dependent on the use of biomass consisting of firewood, charcoal, twigs,straw, crop residues, and cow dung to meet its energy demands for cooking and other domesticneeds. It is estimated that the domestic biomass consumption for fuel is as high as 94% withvery little use of modern sources of energy such as electricity and liquefied petroleum gas (LPG).The use of biomass as fuel has serious ill effects such as degradation of environment due todeforestation, loss of soil fertility due to diversion of animal manure which acts as fertilizer andvarious health hazards particularly associated with rural women and children. It is estimated thatin the past 50 years the land covered by forest has dropped from approximately 50% to less than3%. Some experts attribute this mostly to forest clearing for cultivation and cutting trees for fuel,activities highly exasperated by population growth which is estimated to occur at an averageannual rate of 2.6%. The current rate of deforestation is estimated to cover 200,000 hectares ofland per year. Unless the rate of deforestation is arrested, Ethiopia could lose all its naturalforests in 20 years. The use of cow dung and other animal manure as a source of fuel might beconsidered responsible, at least in part, for reduction in soil fertility and reduced crop yield.Biomass combustion in households using traditional three stone fire place that lacks anyprovision for smoke exhaust exposes particularly women and children to smoke containingharmful products. Prolonged exposure to smoke is responsible for coughing, wheezing, acuterespiratory infection, chronic obstructive lung disease, adverse pregnancy outcomes and lungcancer. Deforestation has made fire wood scarce as a result of which women and their youngones are forced to spend more time in fetching fire wood. In addition to being a heavy burden,fire wood fetching, in conjunction with other factors, is taking so much of the time of childrenthat it may be said to be adversely affecting the literacy rate due to non-availability of time foreducation.In light of the reasons stated above, it is felt imperative that Ethiopia develop an alternativeenergy source that ensures sustenance and availability of its fuel wood or derivatives thereof.Generation of biogas by anaerobic digestion of animal manure particularly cow dung, humanexcreta and kitchen waste is considered to be one such alternative. The technology of biogas hasbeen successfully used in India and China since last 50 years and until now 3.8 million and 5million domestic biogas plants have been installed in India and China, respectively.
In May 2007 a massive program “Biogas for better life: An African initiative, integratedbiogas and sanitation programs in Sub-Saharan Africa” was launched in Nairobi. Thepurpose of this initiative is to provide 2 million biogas digesters to the households in Sub-Saharan Africa over a period of 15 years. According to this program 10,000-14000 biogas plantswill be installed in Ethiopia by 2013.This ambitious program envisions the use of cow dung and human excreta as the main source forbiogas generation using fix dome bio digester. Although the digester can be used for a longperiod of time, it has several drawbacks. Most importantly, it is highly costly in light of the ruralEthiopian economy. The cost of each digester is estimated to be Birr 7500 out of which ahousehold will have to contribute Birr 4300 and the balance will be given in the form of subsidy.There is also micro credit loan provision for the households. In spite of subsidy and loanprovision it is felt that installation of biogas digester under the Africa Initiative Program will putfinancial burden on the households. In the present project, it is proposed to introduce a low costdigester of plastic tank like the one used for water storage along with kitchen waste as source forbiogas generation. Thus the present project will deviate from the Africa Initiative Program onbiogas on two counts. Firstly, it is intended to use kitchen wastes as source for biogas generationin place of cow dung and human excreta. Secondly, low cost plastic tank digester shall be used inplace of expensive underground fix dome digester. It is envisaged that the cost of plastic tankdigester will be half of that of the fix dome bio digester proposed by Africa Initiative Program.The successful outcome of the project will provide a low cost biogas technology with alternatesource. The project will also support the government’s initiative in popularizing the biogastechnology which has already been successfully utilized in India and China and will also help theUniversity to fulfill one of its goals of social transformation for better living through researchand development.
1. IntroductionIn order to understand the need for the development of low cost technology for the generation ofbiogas as a renewable source of energy to address environmental and health issues on long termbasis, it is necessary to understand the present practice of household energy consumption and itsdevastating impact on environment and health of rural and urban poor population. In Ethiopia 85-90% of the population is dependent on traditional biomass (e.g. firewood,charcoal, twigs, straw, crop residues, and cow dung), to meet their household energy needs. Theother available sources of energy are kerosene, electricity and LPG. The consumption pattern ofthese energy sources by households is given in Table 1. Table 1. Energy consumption pattern by households in Ethiopia* Variable Fuel type Households Distribution of Elec., LPG 1.4% household Kerosene by fuel type Charcoal 1.3% Firewood 81.3% Other (cow dung, 16% Crop waste, twigs Etc) % households using Elec., LPG 1.40% purchased fuel Kerosene Charcoal 1.30% Firewood 20.35% Total 23.05% % households collecting 77.1% Firewood *Source: Biogas for better life: An African initiative 2007Table 1 indicates the % households consuming different types of energy sources. Table 2indicates the energy consumption pattern in rural Ethiopia
Table 2 Energy consumption pattern in rural Ethiopia Energy source % consumption Kerosene 3.0 Electricity 1.0 Crop residue 12.0 Cow dung 7.0 Firewood and 77.0 Charcoal Source Kieflu et.al Research Journal of Forestry 2009Thus 77% of total energy consumption consisted of firewood and charcoal while another 19%consisted of agricultural residues; only roughly 4% was met by modern energy sources such askerosene and electricity.There is also a difference in the energy consumption pattern between rural and urban populationas indicated in Table 3 Table 3 Energy consumption pattern between rural and urban population Energy type Consumption % Rural Urban (Addis Ababa) Firewood 85 32 Crop residue 12.7 8.0 Charcoal 2.0 5.0 Kerosene 0.21 42 Electricity 0.05 6.5 LPG 0.07 6.5 Source Ethiopian central statistical Authority 2004Table 1-3 indicate that there is high dependency of large population on fire wood andagricultural waste which is responsible for serious environmental and health issues.1.1 Environmental issuesDeforestationThe most significant implication of high dependency on biomass for fuel is its association todeforestation. The wide spread practice of wood cutting for fuel is the primary cause of
deforestation in Ethiopia. Historically, Ethiopia was one of the “forest” rich nations in theworld. In just the past 50 years the land covered by forest has dropped from approximately 50%to less than 3%. Some experts attribute this mostly to forest clearing for cultivation and cuttingwoods for fuel and other purposes. All these practices have been on the rise, presumably due topoor management and a rapid rate of population growth. The current rate of deforestation isestimated to be 200,000 hectares of land per year. In fact a recent National Geographic Magazinestated that at the current rate of deforestation, Ethiopia could lose substantial proportion of itsnatural forest in 20 years. As a result of this relentless deforestation, large areas are now exposedto heavy soil erosion. In fact at this current rate of deforestation, it is estimated that fertile topsoilis lost at a rate of 1 billion cubic meters per year resulting in a massive environmentaldegradation and serious threat to sustainable forestry. Due to this forest degradation, increasingnumbers of Ethiopians have become vulnerable to the effects of drought. The severity of thedevastating droughts and the resulting famines in 1972/1973 and 1984/1985 can be attributeddirectly to an accelerated deforestation due to wood cutting for fuel and land clearing forcultivation. The wide spread practice of using wood, cow dung and crop residues for fuel,coupled with a rapidly growing population, will undoubtedly increase and hasten thesusceptibility of open land to erosion unless alternate renewable source of energy is introducedas a substitute to biomass burning.1.2 Health issuesIn-door air pollutionAs discussed earlier, biomass fuels such as wood and its derivatives are used widely indeveloping countries like Ethiopia, especially in rural and poor urban areas. In addition, due tothe use of traditional three stone fire in open air the burning efficiency is only 5-10% compared70 - 80% when energy efficient stove is used. The biomass is composed of complex organicmatters including carbohydrates that contain carbon, nitrogen, oxygen and other elements intrace amounts. Smoke emission during burning of these domestic fuels is the major source ofindoor air pollution, especially in rural and poor urban communities. This smoke containspollutants and particulates that adversely affect the health of women. In rural areas, infants aregenerally cradled in the back of their mothers who are doing the daily gathering of fuel andcooking which exposes them to these harmful products. These pollutants are the major causes
of chronic bronchitis and lung diseases. A further concern related to indoor air pollution is thelevel of carbon monoxide production during cooking and baking. Carbon monoxide exposureresults in higher fatal carbon monoxide–hemoglobin (COHb) interaction. This has a more severeeffect on pregnant women resulting in either fetal damage or low birth weight of infant.World Health Organization (2004) estimates that, indoor air pollution due to smoke results in 1.6million deaths worldwide each year, 24% of which occur in Africa; the primary cause of thisindoor air pollution is traditional fuels burned in highly inefficient stoves. Ethiopiansundoubtedly take their toll in this count. Such indoor air pollution is responsible for coughing,wheezing, acute respiratory infection in children, chronic obstructive lung disease, adversepregnancy outcomes and lung cancer.World Health Organization (2006) estimates that 50% of worldwide deaths of children under theage of five are caused by indoor air pollution due to smoke. In Ethiopia, the proportion of deathsdue to indoor air pollution among the children under the age of five is a staggering 80%.Burden on womenAs the degree of deforestation increases, so does the amount of time spent on searching forfirewood. This burden for survival is carried almost entirely by women. In villages, women haveto spend more times in fuel collection. In a poor country like Ethiopia, studies have shown thatwomen spend between 11-14 hours for daily chores. This heavy workload in the long run willaffect their health. This is because the energy expensed is more than the intake of food toaccomplish daily task.Time spent by women According to World Bank (2006) report, not only do rural Ethiopian women travel up to 12kilometers from their home to gather fuels, but they are also forced to collect inferior fuels in theform of bushes, twigs, roots, and crop residues, all of which translate into longer preparation andcooking times. The same is true for urban poor women who also operate under extremely harshconditions and, like their rural counterparts, have to walk long distances on harsh terrain, oftenbarefoot, and with heavy loads. Traditional healers often treat women for severe abdominalpains attributed to carrying these heavy loads over long distances.
Effect on literacyThe more time spent on collection and preparation of biomass for domestic fuel, the less time isavailable for pursuing more productive activities such as education. This is unfortunate in acountry where, in 2003, only 41.5% of the adult population was literate and only 57.4% of theyouth population was literate (UNDP, 2005). With heavy workloads and low-income livelihoods,women also cannot manage without their children, particularly their daughters. The effect of thisis that 46% of those eligible are enrolled in primary schools, and just 15% of those eligible areenrolled in secondary schools.1.3 AlternativesFuel efficient stove is not a permanent solutionThe environment and health issues enumerated above are points of concern to Ethiopia as well asmost of the developing countries. Several national and international programs have beeninitiated in developing countries including Ethiopia to address environment and health relatedissues emanating from burning of biomass as a source of household energy. One such programis the development of fuel efficient stove. However, the fuel-efficient designs of stoves forcooking do not address the environment and health issues on permanent basis but only prolongthe devastating environment and health problems. Therefore, the technology of fuel efficientstove, though useful, is not a permanent solution to the environment and health issues.Biogas as an alternate source of energyAs stated above, unless an appropriate intervention geared towards the development ofalternative renewable energy source is instituted in the near future, Ethiopia will find itself in adangerous situation in terms of sustaining the availability of fuel wood or its derivative. Thusdeforestation and health hazards cannot be reduced without providing alternatives to the currentway of cooking. In the absence of alternate renewable source of energy, people will continuerelentless deforestation that will endanger the eco-system and their lives beyond repair.Generation of biogas from cow manure, human excreta and kitchen waste is considered to beone such alternative. The present project will focus on exploring the feasibility of the use ofkitchen waste as an alternative source of biogas to address the household energy demand in anenvironmentally and user friendly way.
1.4 What is Biogas?Biogas is the gas produced by anaerobic digestion of waste materials of plant and animal origin.Biogas is a mixture of methane (60-70%), carbon dioxide (30-40%) and traces of other gases likehydrogen sulphide and hydrogen. Methane in biogas provides a source of fuel without smoke.Anaerobic digestion (AD) is the process by which plant and animal material is converted intouseful product by micro-organisms in the absence of air. Biomass is put inside a sealed tank andnaturally occurring micro-organisms digest it, releasing methane that can be used to provide heatand power. The material left over at the end of the process, known as bio-slurry, is very rich innutrients so it can be used as fertilizer.This means that generation of biogas is carried out by using waste materials of plant or animalorigin which can be potential source of environmental pollution if disposed off withoutconversion. Most importantly, it provides an alternate source of renewable energy and thusreduces the burden on the use of biomass as well as fossil fuel as a source of energy. The bio-slurry provides organic fertilizer which, unlike synthetic fertilizers, imparts no detrimental effecton soil as well as environment.1.5 Benefits of biogasDeveloping country context including EthiopiaThe benefits of biogas are now well recognized. It has resulted in a smoke-free and ash-freekitchen, so women and children are no longer prone to respiratory infections, and can lookforward to longer, healthier lives. Women are spared the burden of gathering firewood. Cowdung, which is burnt as fuel, can be saved as fertilizer. Both these factors will contribute toprotecting the forests and allowing the forests to regenerate. The sludge remaining after digestionis rich in valuable nutrients and can be used as top quality fertilizer that guarantees better crops.In rural areas where there is no electricity supply, the use biogas as a source of light has enabledwomen to engage in evening study, has made easier literacy classes and other home andcommunity activities.Cattle dung is no longer stored in the home, but is fed directly to the biogas digester along withtoilet waste. The anaerobic digestion process also destroys pathogens. As a result, sanitation hasgreatly improved.
Global contextDisposal of domestic and industrial waste is normally carried out in the form of landfills. Withincreasing population size and industrialization, the spaces available for landfills are decreasing.Beside, the waste materials so disposed also become a source of environmental and healthhazards due to harmful gases that are released upon decomposition of organic materials in thewaste. Such gases are popularly known as green house gases which are responsible for thephenomenon known as global warming. Thus, the conversion of organic solid waste (plant andanimal origin) and converting it into biogas, which is used as fuel for domestic use or forgeneration of electrical energy, provides an eco-friendly solution to the recycling of solid waste.The United Nations Framework Convention on Climate Change has set up a Clean DevelopmentFund, and the World Bank has put together a Carbon Finance Unit to allow rich countries, whichare pumping more carbon into the atmosphere than is allowed under the Kyoto Protocol, to buyemissions that poor countries prevent through conserving forests or promoting renewable energy.This is known as carbon credit. An article in the Nepali Times pointed out that Nepalssuccessful biogas program not only brought farmers a non-polluting fuel, conserved forests andprovided high quality fertilizer for crops. Moreover, Nepal also benefits in terms of hard cashreceived from the industrialized nations for not burning firewood to release carbon dioxide intothe atmosphere.1.6 Substrates used for anaerobic digestionAny organic matter of vegetable or animal origin can be used for conversion into biogas througha process of anaerobic digestion. Typically substrates used for biogas generation are as follows • Sewage sludge (human excreta) • Food waste • Waste from food industry • Manure from cows, pigs etc. • Residues from agriculture1.7 Methane content of different substratesFollowing table shows the biogas yield from different substrates that can be used for biogasgeneration.
Table 4 Methane content of few waste substrates* S.No Substrate Biogas yield M3 kg-1 1 Pig manure 0.25-0.50 2 Cow manure 0.2-0.3 3 Chicken food waste 0.35-0.60 4 Human excreta 0.03 m3/person 4 Fruit and vegetable waste 0.25-0.50 5 Food waste 0.5-0.6 6 Garden waste 0.2-0.5 7 Leaves 0.1-0.3*Source: Basics of Energy Production through Anaerobic Digestion of Livestock Manure Purdue Univ. publication 20081.8 Biogas digester technologiesBiogas digesters can be divided into two categories A. Industrial bio digesters B. Domestic bio digestersIndustrial bio digesters are mainly used in developed countries for the anaerobic digestion ofmunicipal solid waste to release the pressure on landfill sites. The biogas thus generated ismainly used for electricity production.Domestic bio digesters are most popular among the developing countries because of thepossibility of generation of biogas on small scale at household level. The gas generated is used asa fuel to minimize the use of biomass as fuel.Following types of domestic biogas digesters are popular for small scale production of biogas 1. Fixed dome digester 2. Floating dome digester 3. Plastic bag digester 4. Inclined digester
The technical details of the digester technologies are beyond the scope of the present projectproposal. Only the salient features are mentionedAmong these, the fixed dome digester, though expensive, are most widely used because of theirlong life. There are, however, some disadvantages associated with the use of fixed dome digesterand these are indicated in the problem statement section. Fixed dome digesters are constructedunderground. Digesters of 4, 6, 8, 10 M3 size are popular for small family having 2-6 cattle.Being expensive, these digesters are mainly installed at the institution level. Installation byindividual household has been possible only through subsidies.The floating plastic dome, plastic bag and inclined digesters are economical. Among these theplastic bag digester is most economical but very delicate and need considerable precautionsduring its handling and thus have only short life. The other two types i.e. floating dome/ inclineddigesters will be explored for the production of biogas during the present project.1.9 Biogas program in few developing countriesGlobally, biogas technology seems to have outnumbered the dissemination of other decentralizedenergy technologies, with a reported 16-25 million units installed worldwide.Biogas digester technology is well established as an appropriate sustainable energy source inmany parts of the developing world. The technology has been implemented on large scale inChina, India and Nepal.Majority of developing countries including Ethiopia have national programs on biogasgeneration. All these programs are supported by national and international funding. Subsidyvarying between 30-75% is given to households in order to popularize the program. Followingtable will give an idea of domestic biogas installations in few developing countries. Though thedata includes only limited countries, it is enough to understand the importance of the biogasprogram and its relevance to Ethiopia.
Table 5 Biogas installations in few countries Country No. of domestic biogas digester Installations World wide 16-25 million China 5 million India 3.8 million Nepal 155,000 Vietnam 25000 Combodia 17500 Ethiopia 1000 Tanzania 1000 Kenya 150 Source: Assorted1.10 Biogas for better life: an African initiative, integrated biogas and sanitation programs in Sub-Saharan AfricaIn May 2007 the “Biogas for Better Life: an African Initiative” was launched in Nairobi. Thepurpose of this initiative is to provide 2 million domestic biogas plants to households in Sub-Saharan AfricaThe initiative aims to achieve the following by 2020: • 2 million biogas plants installed (90% operation rate) • 10 million Africans benefiting in daily life from the plants • 800 private biogas companies and 200 biogas appliances manufacturing workshops involved or established • 100,000 new jobs created • comprehensive quality standards and quality control systems developed and in use • 1 million toilets constructed and attached to the biogas plants • 80% of the bio-slurry utilized as organic fertilizer • agriculture production raised by up to 25% • health and living conditions of rural household improved and death of rural household reduced by 5000 each year • drudgery reduced by saving 2 to 3 hours per day per household for fetching wood,
• cooking and cleaning the pots • health costs saved by up to US$ 80 to 125 per family per year • 3 to 4 million tonnes of wood saved per year • Greenhouse gas emissions annually reduced by 10 M tonnes of CO2 equivalent.The African countries and the Organizations involved are given in the following table Table 6 Organizations involved in Biogas-Africa initiative program Organization African CountriesGerman Technical Cooperation (GTZ) Burkina Faso, Rwanda, Tanzania& Biogas Africa InitiativeNetherlands Development Organization (SNV) Burkina Faso, Cameroon, Ethiopia,& Biogas Africa Initiative RwandaETC Foundation & Biogas Africa Initiative Sudan, Kenya, UgandaWest African Economic and Monetary Benin, Guinea Bissau, Niger, Togo, SenegalUnion (UEMOA)& Biogas Africa InitiativeAll the above organizations All countries in Sub-Saharan Africa (SSA) Source Biogas for better life: An African initiative 2007The country wise plan for domestic biogas plant installations is as follow: Table 7 Country wise plan for domestic biogas plants Country No. of biogas plants to be installed Ethiopia 10000-14000 Uganda 20,000 Rwanda 15000 Tanzania 12000 SSA 2 million countries Source Biogas for better life: An African initiative 2007The program for Ethiopia, Uganda, Rwanda and Tanzania will continue for five years (2013)and for other SSA countries it will continue for 15 yearsFinance
The total financial requirements are summarized in Table 8 Table 8 Financial requirements for biogas installations Country Targeted Total subsidy Total cost No. of plants US $ US $ Uganda 20,000 4,000,000 44,627,282 Rwanda 15,000 4,500,000 34,959,357 Ethiopia 10,000 1,860,000 23,774,625 SSA 2 million 400,560,000 4,306,057,409 countries Source Biogas for better life: An African initiative 2007 The importance given to the biogas program for better life will be clear from the above tables.2. Problem statementLike other developing countries, the rural population and poor urban population in Ethiopia; isentirely dependent on the use of biomass consisting of firewood, charcoal, twigs, straw, cropresidues, and animal dung as a source of fuel. This is responsible for serious environmentaldegradation due to deforestation, poor health of households particularly women and children andheavy work burden. The heavy work burden on women and children is indirectly responsiblefor poor literacy. Therefore, there is urgent need to provide economical and sustainable alternatesource of energy to minimize deforestation, improve living standards and literacy of ruralmasses. Biogas, which consists of methane as a major component, is considered to be one suchalternative renewable source of fuel. The biogas can be produced on small scale by householdsusing cow manure, human excreta and kitchen waste using suitable digesters. The governmentinitiative launched in 2007 envisages setting up 10,000 to 14000 domestic biogas plants inEthiopia by 2013. The technology adopted is based on fix dome digester. It is estimated that thecost of each biogas plant of 6 m3will be ETB 7500, out of which each householder will have tocontribute ETB 4300 and balance money will be provided as subsidy. The Government has alsoplans to provide loan facility to the householders for his/her contribution. It is strongly felt thatwith the present economic conditions among the rural population the contribution towards thecost of biogas plant will be heavy burden on the householders.
3. Drawbacks of fixed dome digesterThough the fixed dome digester has long life, it is associated with the following drawbacks. 1. The digester is expensive for rural economy in the absence of subsidy and loan facility, the provision of which has been made in the national biogas program. 2. The dome is constructed underground where the temperature is lower compared to surface temperature, whereas the performance of anaerobic digestion is better at higher temperature. 3. For construction of 6 m3 digester, the free space required is 18x18x18 ft, which may not be available with many households. 4. The brick construction often develops cracks from which gas can leak. The digester being underground it will be difficult to locate such cracks. Hence the required quantity of gas may not be available. 5. The digester needs supervision, which may not be provided by every household.4. Substrate for biogas generationIn the Government initiated national program of biogas, the substrate used will be cow dung andhuman excreta. The philosophy behind this choice is to provide hygienic living environment inaddition to biogas generation. Though the choice of the substrate is ideal, there are psychologicalbarriers associated with the use of human excreta. Also the size of biogas digester suggested inthe national biogas program is 6 m3 which will need feeding of minimum 20 kg of cow dung perday. For this every household will need a cattle stock of 4-6 cows. This may not be possible withevery household.For the reasons stated above, it is suggested in the present project proposal to use food andvegetable waste which is always available in the household as a substrate for biogas generation.In the present project proposal it is proposed to overcome the difficulties associated with thefixed dome digester. It is proposed to use low cost plastic tank digester like the one used forwater storage. The digester will be fixed on the ground. The digester will be easy to superviseand maintain. It is envisaged that the cost of the proposed biogas plant will be almost half of thecost estimated in the Government initiated national biogas program.
Secondly the choice of the substrate will be kitchen waste in place of cow dung and humanexcreta suggested in the national biogas program.Thus on both accounts i.e the choice of low cost digester technology and the choice of substratefor biogas generation the present project is different but supplementary to the national biogasprogram. It is therefore strongly felt that the outcome of the present project will support thegovernment initiative in popularizing the biogas technology for better living and to minimize thedanger of deforestation.3. ObjectivesGeneral ObjectiveThe principal aim of the project is to implement low cost biogas generation technology inaddressing environmental and health issuesSpecific objectives 1. To use plastic tank digester like the one used for water storage. The tanks will be placed on the ground rather than underground. 2. To use kitchen waste (left over food and uncooked vegetable waste) as a source for biogas generation instead of cow dung and human excreta. 3. To study the biogas yield and its sufficiency for meeting the fuel requirements of a family. 4. Testing the technology in three households to get the feedback for any improvements if required. 5. To workout the cost and economics of the technology 6. Showcasing the technology in the form of workshop to government and private agencies and households for further dissemination.4. Method and DesignThe following methodology will be adopted for the implementation of the low cost digestertechnology of biogas generation using kitchen waste. 1. Appointment of researcher or 2 Graduate students to work on the project under the supervision of project investigators 2. Market survey and purchase of suitable plastic tanks and other accessories needed for the construction of digester.
3. Digester construction 4. Collection of kitchen food waste from student cafeteria in the form of cooked food waste and uncooked vegetable and other wastes of organic origin. 5. Standardization of parameters for anaerobic digestion of collected waste and estimation of biogas yield. Most important parameters will be pH, temperature and initial time required for biogas generation and subsequent feeding of waste for continuous availability of gas for daily use. 6. Analysis of difficulties faced and their solution. 7. Installation of biogas digester in three households to get the feedback of their experiences and further improvement if any. 8. Report writing. 9. Conducting workshop inviting the government and private agencies and households for further dissemination of technology.5. Project time schedule S.N Activity Time required o Months1 Visit to existing biogas generating sites in/near Bahir Dar Two weeks2 Appointment of Researcher 1 month3 Market survey for purchase of items required and assembly of 1 month digester4 Collection of food waste and initiation of anaerobic digestion (Initially 2 months minimum 1.5-2 months are required for generation of biogas).5 Standardization of process parameters for getting optimum biogas 6 months yield on continuous basis6 Field testing of technology by setting 3 biogas digesters in three 6 months households for feedback and further improvement if needed7 Report writing 1 month8 Workshop preparation for inviting stakeholders for further 1 month dissemination of technology Total period 18.5 months
6. Project budget S.No Component Amount ETB 1 Salary of researcher (2 Graduate students) 27,000 @1500 ETB per month for 18 months 2 4 Plastic tanks and accessories 20,000 For installation of bio digester (1 for research and 3 for Field testing of technology) Estimated ETB 5000 per digester Including labor charges for assembly of digester 3 Workshop for technology 10,000 Dissemination (Travel cost, tea, lunch/snacks to invited stake holders, households, 4 Report writing (Stationary, computer 2.000 Peripherals, secretarial assistance) 5 Travel during the project period 5,000 6 Contingency 6,400 Total 70,400
References1. Urban Fuel Demand in Ethiopia, Zenebe Gebreegziabher, Arie J. Oskam and Demeke Bayou, Environment for Development, (August 2010)2. Wood fuel demand and sustainability of supply in south western Ethiopia (2009), Kiflu haile, Mats Sandewall, Kaba Urgessa, Research Journal of Forestry, 3(2), 29, 20093. Human waste based biogas plant design for Universities in Ethiopia; a case study in Bahir-Dar University, faculty of engineering, Moges Ashagrie MSc thesis 20094. Biogas Generation from Human Excreta A multi-dimensional Sanitation Approach- Experience of Lem Ethiopia, Mogues Worku, Presented at the 3rd International Dry Toilet Conference, Tampere, Finland August 12-15/ 20095. Biogas in Ethiopia: From Skepticism to Enthusiasm, Willem Boers & Getachew Eshete, SNV Ethiopia Document 20096. National Biogas Program-Ethiopia, Program Implementation Document January 20087. Biogas for better life: An African initiative, A cost-benefit analysis of national and regional integrated biogas and sanitation programs in Sub-Saharan Africa , April 20078. Commercialisation and business development in the framework of the Asia Biogas Program, Wim J. van Nes, Seminar on “Policy options for expansion of community-driven energy service provision” Beijing, China, 11-12 March 20079. Household determinants of fuel wood choice in urban Ethiopia: a case study of Jimma town, Abebaw, Degnet, Journal of Developing Areas, 200710. Biogas Bonanza for Third World Development http://www.i- sis.org.uk/BiogasBonanza.php, 200511. Use of biomass-Ethiopia, GTZ, Germany, 200412. The economics of a biogas digestorhttp://www.ilri.org/InfoServ/Webpub/fulldocs/Bulletin30/economi.htm13. Kitchen Waste Based Biogas Plant, http://www.dae.gov.in/ni/ninov02/biogas.htm14. Wood fires that fit, http://journeytoforever.org/at_woodfire.html15. Occupational, Health Hazards of Improper Garbage Disposal, www.addisfortune.com/agenda.htm16. Household Energy Use in Ethiopia http:// http://www.hedon.info/Ethiopia17. The making of Injera/Enjera: http://www.zelaleminjera.com/products.html18. Cook stove for Ethiopia, http://newscenter.lbl.gov/feature-stories/2010/06/29/berkeley-lab- makes-cookstoves-for-ethiopia/
9. Curriculum Vitae of investigators1 Dr. Solomon LibsuProf. R B ChavanEducational background No Field of study Degree Class Year university completion 1 Chemistry B.Sc.(Hons) First 1964 Marathwada Univ. India 2 Textile B.Sc.(Tech) First 1966 University of Bombay, India Chemistry 3 Textile M.Sc. First 1968 University of Bombay, India Chemistry (Tech) 4 Textile Ph D (Tech) 1974 University of Manchester, Chemsitry Inst. of Science and Technology EnglandAcademic achievements S.No. Academic achievements Number 1. Total teaching experience at 30 years Indian Inst. of Technology, Delhi, India 2. Experience as Professor 20 years 3. Head of Department 3 years 4. Industrial experience 04 years 5, No. of Ph.D students guided 11 6. No. of M.Tech students guided More than 50 7. Publications International 30 National 53 Paper presentations 43 Total 126 8. Sponsored projects International Agency 01 Govt. Agency 03 Industry 03 Major consultancy INR120 million 01 Books edited 04 Books published 02 Special Journal issue edited 01
Chapter contribution in International 01 Book on dyeing Book accepted for publication (Book 01 on Ethiopian textile Ind. written after joining Bahir Dar University in 2009Present employmentProfessor, Inst. of technology for Textile, Garment and Fashion design (IoTex), Bahir DarUniverisy, Bahir Dar, EthiopiaPeriodOctober 2009 till date.Research profile1. Technical interventions for the development of hand spinning and hand weaving sectorin rural IndiaManual spinning and handloom weaving is prevalent in rural India. Fabric thus produced isknown as khadi. Khadi and Village Industries Commission under the Ministry of Micro, Small,and Medium Enterprises (MSME) is responsible for the development of the Khadi sector. Thesector provides employment opportunities to large number of rural population. Themanufacturing activities being carried out on small scale using traditional technologies, thesector is deprived of modern technical interventions.Following technological inputs have been provided and implemented in the field 1. Preparation of Quality assurance manual for yarns and fabrics 2. Product design development 3. Transfer of the technology of fabric and garment finishing 4. Standardization and transfer of the technology of dyeing with natural colors 5. Development of solar energy operated mini-spinning unit for removal of drudgery of manual spinning operation and improvement in productivity and quality of yarn produced. The technology has been accepted by the Ministry of MSME and implemented in the khadi sector on all India basis2 Environmentally friendly chemical processingThe research activities were supervised at the master and Ph D level in the following areas
1. Replacement of hazardous sodium sulphide with eco friendly glucose during dyeing of cotton with sulphur dyes.2. Development of eco-friendly reducing system based on sodium gluconate for dyeing of cotton with vat dyes.3. Transfer printing of cotton and polyester cotton blends4. Development of solubility parameter concepts for better understanding of transfer printing mechanisms