Presentation on theme: "ECONOMICS OF BIOGAS PLANTS AND THEIR ROLE IN SAVING THE ENVIRONMENT."— Presentation transcript:
ECONOMICS OF BIOGAS PLANTS AND THEIR ROLE IN SAVING THE ENVIRONMENT
Biogas, its composition and uses Energy equivalence and Commonly used organic matter for biogas generation Overall scheme for anaerobic digestion of organic matter Nutrient Contents of Digested Slurry from biogas plant and FYM Types of biogas plants Role of Biogas plants in saving of environment Status of biogas development in India Economics of family size biogas plants
What is Biogas A gas obtained due to anaerobic decomposition of organic matter (cattle dung) It is a mixture of methane, carbon dioxide, hydrogen sulphide, water vapor, oxygen, nitrogen and hydrogen. Biogas has been known as swamp gas, sewer gas, fuel gas, marsh gas etc. In India, it is more commonly known as ‘gobar’ gas. The digester in which the decomposition takes place is known as BIOGAS PLANT
Composition of Biogas Methane 50-70% Carbon dioxide 30-45% Hydrogen 0-1% Nitrogen 0-1% Water 0.1% Hydrogen sulphide 0-1% Oxygen 0-1%
Common Uses of biogas Cooking Lighting Power generation Engine running
Energy Equivalence of biogas Use of 1m 3 of biogas as fuel can save other sources of energy as: 0.52 litre of diesel 0.62 litre of kerosene oil 3.40 kg of wood 12.30 kg of cow dung cakes 0.43 kg of LPG 1.46 kg of coal 4.70 KW of electricity
Commonly used organic matter used for generation of biogas Cattle dung Kitchen and dining hall waste Vegetable market waste Poultry dropping Crop residue Pig and horse excreta Aquatic weeds such as water hyacinth Agro industrial waste Sewage Sludge
Comparative Biogas Production of Different Feed Stocks S NoType of feed stockGas Yield per Kg ( m 3 ) Normal Feed availability per animal per day (Kg) 1Cattle dung0.03610 to 15 2Human excreta0.070.5 3Horse dung0.04510 4Sheep dropping0.0421 5Camel droppings0.0566 6Piggery waste0.082.25 7Poultry droppings0.0620.18
Overall scheme for anaerobic digestion of organic matter 1 st Phase- hydrolysis of complex organic materials, i.e.,carbohydrates,fats,proteins, nitrogen compounds,salts etc. into soluble organic compounds, i.e., sugars,fatty acids,amino acids etc. 2 nd Phase- soluble organic compounds are reduced to simpler compounds, i.e., organic acids (acetic acid, propionic acid etc.), simpler alcohols and acetone. 3 rd Phase- Organic acids,mainly acetic acid and certain other oxidised compounds are converted to methane and carbon dioxide by methanogenic bacteria.
Nutrient Contents of Digested Slurry from biogas plant and FYM S.No.NutrientFYMBiogas slurry Range %Average %Range %Average % 1.Nitrogen (N 2 ) 0.5 to 1.00.81.4 to 1.81.6 2.Phosphorus (P 2 O 5 ) 0.5 to 0.80.71.1 to 2.01.55 3.Potash (K 2 0)0.5 to 0.80.70.8 to 1.21.0 Source: Biogas Technology: A training manual for extension, FAO
TYPES OF BIOGAS PLANTS FLOATING DRUM TYPE FIXED DOME TYPE –JANTA BIOGAS PLANT –DEENBANDHU BIOGAS PLANTS
Modified Deenbandhu and Janta biogas plants The inlet in the traditional biogas plant is designed and modified by providing 12 inch dia pipe inclined at about 75 degrees with horizontal. The outlet is accordingly modified as per requirement The water requirement :30 % of cattle dung as compared to 100 % of cattle dung in traditional biogas plants Digested Slurry is more thick hence easy to manage
Modified Janta biogas plant Inlet 30 cm diameter PVC pipe Angle of inclination of pipe with horizontal=75 o
DEMONSTRATION OF MODIFIED JANTA BIOGAS PLANT AT THE RESIDENCE OF SH. TARSEM SINGH, RURKI KHURD
DEMONSTRATION OF MODIFIED JANTA BIOGAS PLANT AT THE RESIDENCE OF MANJEET KAUR, BHARBHURGARH
DEMONSTRATION OF MODIFIED DEENBANDHU BIOGAS PLANT AT THE RESIDENCE OF LABH SINGH, BEEPUR
Role of Biogas plants in saving of environment Direct and immediate impact : –Save other fuels and hence less stress on other fuels –Using biogas as a kitchen fuel can prevent deforestation and hence soil erosion –Change of environment in the house as biogas is a clean fuel. Other fuels being commonly used creates pollution by generating smoke. –The use of biogas prevents chances of eye diseases and respiratory diseases. Hence healthy life of rural woman. –Clean kitchen and utensils and hence saving in the time of women –Clean House and hence less expenditure for maintenance of house
Role of Biogas plants in saving of environment (contd) Reduction in green house gases: –How?
Green house gases The gases which trap heat in the earth's atmosphere and cause rise in temperature are known as green house gases. –Greenhouse gases are the major cause of global warming. Different green house gases Naturally present green house gases in the atmosphere –carbon dioxide, –methane –nitrous oxide –water vapor and –ozone Green house gases due to human activities –hydroflurocarbons (HFCs) –perfluorocarbons and –sulphur hexafluride.
Some activities responsible for green house gases Agriculture and industrialization Fossil fuel burning like that of coal in power plant leads to high emissions of carbon dioxide gas. Methane generated during Anaerobic decomposition of organic material Emission of nitrous oxides due to nitric acid production, use of cars with catalytic converters, the use of fertilizers in agriculture and the burning of organic matter.
Kyoto Protocol for Control of green house Gas emission An international agreement signed (December 1997) by about 180 countries with the aim to reduce green house gases emissions in order to save the environment Countries have been assigned maximum carbon emission levels and can participate in carbon credit trading.
Carbon Credit system and carbon trade The carbon credit and carbon trade system was ratified in conjunction with the Kyoto Protocol. Its goal is to stop the increase of green house gas emissions. For example, –if an environmentalist group plants enough trees to reduce emissions by one ton, the group will be awarded a credit. –If a steel producer has an emissions quota of 10 tons, but is expecting to produce 11 tons, it could purchase this carbon credit from the environmental group. –The carbon credit system looks to reduce emissions by having countries honor their emission quotas and offer incentives for being below them
Potential of methane wrt carbon dioxide as green house gas Green house gas methane is more than 20 times as powerful as carbon dioxide at entrapping heat in the atmosphere. Reaction during burning of methane (biogas). Hence one molecule of methane is converted into one molecule of carbon dioxide and as such the effect of methane will be reduced to 1/20 th of its effect as compared to when it is released as such in the atmosphere.
Theoretical computation of carbon credit for 3 m 3 biogas plant 1 m 3 CO 2 = 0.483 kg of carbon at about 30 o C 1 m 3 of CH 4 = (20-1)0.483 =9.18 kg of carbon For a 3 m 3 biogas plant Estimated biogas generated per day= 3 m 3 Assuming 60 % methane in biogas As such 3 m 3 of biogas = 0.6*3 m 3 of CH 4 = 1.8 m 3 of methane 1.8 m 3 of methane =1.8*9.18=16.52 kg of carbon/day In one year = 365*16.52 =6030 kg of carbon=6 tonne of carbon 1 tonne of carbon credit = 17 Euro Equivalent credit earned in one year by 3 m 3 biogas plant= 102 Euro 1 Euro= Rs 59 102 Euro = 6018 Rs Thus a 3 m 3 biogas plant can theoretically earn carbon credit equivalent to Rs 6018 in one year.
Status of biogas development in India Total potential of biogas plants based on cattle dung in India: 1,23,39,300 Biogas plants installed as on 31-12 2009 : 41,85,442 % of total potential exploited :33.9 For Punjab % of total potential exploited for Punjab :24.7 % of total potential exploited for Punjab :17.8 Change for India in last 2.5 years :2.8 % Change for Punjab in last 2.5 years :5%
S No State/ Union Territories Estimated Potential (Nos. of Biogas Plants) Cumulative achievements* as on 31/12/2009 Percentage of Biogas Plants installed against total potential 1 Sikkim7300 692694.9 2 Maharashtra897000 77341086.2 3 Kerala150000 12420282.8 4 Mizoram5000 377075.4 5 Gujarat554000 40497373.1 6 Karnataka680000 41124160.5 7 Nagaland6700 374355.9 8 Goa8000 387848.5 9 West Bengal695000 30576044.0 10 Andhra Pradesh 1065000 45249942.5 11 Orissa605000 23539338.9
Economics of Family size Deenbandhu Biogas Plants
S.No.ItemCapacity of Biogas Plants (m 3) 3456 1.Estimated cost (Rs.)14000155001650018000 2.Equivalent Biogas produced per month in terms of LPG (Cylinders) 2.573.424.285.14 3.Monthly saving from Biogas in terms of LPG (Assumed cost of LPG cylinder =Rs.330/-) 771102612841542 4.Approximate pay back period of Biogas Plant (years) 1.501.251.101.00 Estimated cost and Payback period for Deenbandhu biogas plants on the basis of saving of LPG
Economics of Family size Biogas Plants The initial cost of the plant can be recovered in a very short time due to savings in the use of alternate fuels. The user will be getting the biogas from the plants for more than 25 years. User is saved from the increase in cost of alternate fuels during the life of plant All the farmers rearing animals should adopt this technology as it requires one time investment and its benefits are derived for rest of the life of plant. Government of India provides an incentive of Rs. 8000/- or 50% of cost which ever is less for the installation of biogas plants.
Economics of Family size Biogas Plants (contd) An additional incentive of Rs 1000/- is provided for connecting the toilet to the biogas digester Attachment of toilet to the biogas plant will decrease the cost of toilet significantly as no separate septic tank will be required for the toilet. Value of the good manure and carbon credit earned has not been considered in computing the payback period. Keeping all the incentive into consideration the initial cost will be recovered in a very short time. There is no major maintenance cost for the plant and the operation of the plant is very simple.
Requirement of dung and number of animals for different size of biogas plants Capacity of biogas plant (m3 ) Approximate No. of animals required Quantity of fresh dung required (kg) Cooking for number of persons 12-3252-3 24-5504-5 36-7757-8 48-1010010-11 613-1515014-16
Alternate model of promoting Biogas programme Some farmers may feel difficulty in arranging the initial capital for installation of biogas plant For such farmers a programme may be framed in which the bank provides interest free loan to the farmers. The loss in to the bank is compensated from the incentives to be provided to the farmers. The direct incentive to the farmers may be reduced in such cases
Installment for 20000/- loan at different rates of interest Rate of Interest Monthly Installment for 20000 loan(Rs) Total Interest paid (Rs) Period of Return (Months) 364860364860 8 643 497411 2491 33634260 7 633.5 488402 2170 29253700 0 571.5 425.5339 000
Hence The use of biogas plants reduces the green house effect due to anaerobic decomposition of organic matter to a large extent and helps to save our environment. Attaching the toilet to the biogas plant will improve the sanitary condition in villages and help in reducing the cost of the toilet. The biogas plants are easily affordable and economically viable and must be installed at a rapid rate to achieve 100 % potential of biogas plants. The investment is one time and the benefits are derived for rest of the life of plant.