| Details of Innovation |
Need for New Model Bio-Gas Plant
To save the Environment
Protect forest and wildlife
Failure of previous models in biogas plant
Moreover, he would be lie to support environmentally sustainable technologies like bio-gas and help it to grow in rural India in new model shall have following points.
To stop deforestation and to increase rain fall
To save environment getting polluted
To stop the people from cutting of trees for fire wood from the forest
To utilize the natural manner in large quantity and quality in the agricultural fields.
In the beginning, public also were not interested to accept the new model of bio gas plant due to following reasons.
1. Failure of previous model
2. Construction cost is very high (Rs.20,000 - 25,000)
3. Easy access for availability of L.P.G. Gas.
To make the public understand, an awareness programme was conducted by Dr. K. Ashokan at village level (Newspaper publicity) and the village people accepted the new model biogas plant.
Reasons for selection of New biogas plant
Minimum space requirement
It can be constructed without using bricks
Construction cost is very less (Rs.7000 - 8000) for cum
Government subsidy is Rs.3500 for biogas plant and Rs.500 extra if latrine attached.
Construction will be completed within 20 days and from 21st day onwards gas can be used for cooking purpose.
Other home waste and meat waste can be used for Bio-gas production.
In this model,the cow shed wastages like urine and dung can be dirctly sent to the biogas plant.
Latrine attached Model
1. Septic tank need not be constructed separately
2. Latrine outlet is directly connected to the biogas plant
3. Latrine waste and cow dung are mixed together to produce more gas. The wastages will come out after 14 days. So there will be no latrine odour. Colour is also changed to that of dung. Nobody can identify whether it is latrine mixed (or) not.
At the time of cooking no one can feel the latrine smell.
Since both toilet and cow dung are mixed we can get more quantity of manure.
Details of Construction
Materials required
1. Cement 2cu.M.- 3Cu.M
2. Sand - 10 Bags - 12 Bags
3. Sand - 1.1/2 tractor - 1.3/4 tractor
4. Stone chips - 10cu.ft. - 13 cu.ft
5. A.C Pipe 6" dia 6 ft - 1no - 1 No
6. G.I. Pipe 3/4 Dia 6" with sucket - 1 No - 1 No
7. M.S. Rod (6mm)-12 kg - 15 kg
8. M.S. Rod (4 MM) 15 Kg - 20 Kg
9. Chicken Mesh (1/2 X 1/2 X 24 guage)- 65m - 80 m
10. Winding wire - 5 kg - 5.5 kg
11. Bio gas stove - 1 No - 1 no
12. Mixe Fan - 1 No - 1 No
13. White Cements - 2 kg - 2.5 Kg
Function of Bio gas plant
1. Filling the Digester
The slurry should be added as quickly as possible. Dung can be collected for about 10 days prior to first filling. However the dung so collected should not be allowed to dry up and become hard as it can not be mixed easily with water to form slurry.
The inlet pipe should be blocked with a piece of wood. The slurry should be prepared as decribed below;
Mix dung with water in 1:1 ration and can be mixed manually (0r) with a piece of wood.
The plug should be removed from the inlet pipe and care should be taken to see that the plug doen not slip down from inlet pipe. While filling the digester with a partition wall (outlet chamber) for the 1st time care must be taken to fill both the compartments. This is done by putting the slurry in equal quantity simultaneously through an inlet pipe and out let chambers.
The slurry should be poured until it starts to over flow through the outlet chamber.
Gas Production:
Initially it takes about 7-10 days for gas holder to become fill with gas. The slurry is retained in the digester for a certain period of time (7- 10 days) for decomposition dung slurry is allowed to ferment in the digester when gas is formed it rises upwards and gets collected in te dome. The pressure of gas pushes the slurry down andcauses its diffusion into the inlet pipe and outlet chambers where slurry level goes up.
The displaced level of slurry provides necessary pressure pushing the gas upto the burner in the kitchen. When gas is consumed the slurry level in the inlet pipe and out let chambers comes down to the initial level. The volume of gas stored in teh plant at given time is equal to the total volume of slurry displaced in the outlet chambers. The plant (dome) should be constructed under the ground as per recommended specifications in order to get calculated gas production.
In a chick mesh covered dome, biogas unit gas is produced at a higher gas pressure and a longer transparent pipe if necessary. The gas holder assembly consists of a central guide frame (dome) it collects gas which comes out of the slurry and moves up when the gas out let is opened the gas so collected is pushed out into the pipe line by the inside pressure. The house pipe should be fitted to the gas holder and tight with pipe clips. The size of the pipe depends upon the distance between the plant and the kitchen . The burner and lamp are now attached to the gas cook by using pressure rubber tubes. The air adjuster of the urner is kept fully closed. A match stick should be lighted the holes of burner and the gas is then turned on slowly. It should be burned with blue flame.
Feed stock
The bio gas generated out of animals and human waste such as cow dung, Urine , House waste, pultry waste other livestock excreta , night soil are used as feed stock.
Effect of cold climate (Hills area)
Biogas production greatly depends on temperature . Theoptimum temperature range is about 30-35 c. During winter season when a temperature level is reduced the production of gas also falls down. In such a situation the following tips may be useful.
a. Warm water can be used for dilution of dung. For this a solar heating system could be used.
b. Organic matter containing a high percentage of nitrogen like Urine, Night soil etc., incrases gas production and improves the quality of manure.
c. Unwanted kitchen wastes, green leaves, grass clippings etc, can be also used for drying, chopping and mixing with cattle dung.
d. The gas holder should be kept covered with plastic sheet (or) gunny bags during night so that it remains insulated and heat loss is minimized.
This type of bio gas plants commonly have been set at attitudes of around 1500MSL and also in nilgiris District.
These plants are functioning well for more thatn 10 months in a year hills area. |
Honey Bee Network Knowledge & Innovation Database (HBNKIND)