A Cost Effective Family Type Biogas Plant with High Efficiency. The cost of a biogas plant depends upon the type of digester used for gas production. The quantity and type of materials used for the making of the plant plant of course play a vital roles in its durability,Efforts have been made to increase the strength and efficiency by the shape of the plant. Also in this case the gas storage volume inside the plant has been increased by 50% compared to 33% storage capacity of that of the Deenbandhu model and Utkal model so far in wide use due to cost effectiveness. Here in Konark model,the cost of construction is reduced by 10 to 15% if constructed with brick masonry and by 30 to 35% if constructed involving ferro-cement technology compared to Deenbandhu model biogas plant. With the spherical shape of a biogas plant,the surface area becomes minimum which ultimately results in reduction in cost of construction of the Konark model...
From time immemorial man has starved to harness energy from nature. The improved method of harnessing of energy is the harbinger of the growth of the civilisation. Science and Technology continues to be on its ficke wings of development. Science is beginning of the creation scientists are making untiring efforts to evolve never and more advanced scientific techniques to make human life easier and more comfortable. In the process many old scientific technique rendered obsolete and were substituted by more appropriate and economic ones. To cater the basic needs of society and to provide a suitable model of biogas plant in order to recycle organic wastes like cow dung which is commonly available in rural households,is a task to the technocrats involved in renewable energy programs. Here,attempts have been made to provide an economical and efficient model of fixed dome biogas plant with increase ages storage capacity for common rural population and best suitable for developing countries.
The proposed Konark model has been tested over a period of one year. This model can be constructed either with brick masonry or involving ferro-cement technology.
With the spherical shape of a biogas plant the surface area becomes minimum which ultimately results in reduction in cost of construction of Konark model. The apprehension of the designers while designing Deenbandhu model and Utkal model biogas plants,questioning the suitability of spherical shape with reference to flushing of input slurry,has been given due consideration. The apprehended short circuiting was prevented by providing a baffle wall with holes inside the digester, in between the inlet pipe and outlet bottom tank. The baffle wall checks and reduces the kinetic energy due to flow of the input slurry from the mixing tank. Hence,the probability of short circuiting is eradicated. The holes of the baffle wall maintain the level during initial loading of the plant and create favorable conditions for the growth of methenogens. The spherical structure acts as digester cum gas storage space with sufficient empty space to accommodate unforeseen casualty. Such spherical structure loaded from the convexportion is under compression and therefore the internalload due to the self weight at the slurry as well as the gas pressure counterbalanced and no residual effect on the structure is noticed. As regards suitability of using building materials to construct Konark model biogas plant, the performance of about 300 Utkal models was tested, which were constructed using ferro-cement technology which is designed and developed by the author. The present topic was studied thoroughly and excellent positive results were confirmed. Hence by using either ferro-cement technology or any other qualitative building materials like brick masonry and concrete,the spherical Konark model can be considered as the most economical & highly efficient with higher gas storage capacity.
- Portland cement of uniform consistency.
- Clean inertsand,free from organic material,salt and clay 2mm grain size.
- Fresh drinking water free from organic matter, oil, chloride,acid and other Impurities.
- For water reduction,in order to increase strength and to reduce permeability Admixture in the does of 150cc per 50 kg of cement can be used.
- Hexagonal G.I.Wiremesh with 15 to 25 mm mesh opening and woven with 20 to 22 gauge is required.
- 4mm G.I. Wires with spacing of 200mm to 300mm are suitable.
Recommended Mix Proportion
- Sand Cement 2.5:1
- Water Cement 0.4
- Spacing between 4mm G.I.Wire is 250mm both ways.
- Players of hexagonal wire mesh.
- Konark model with brick masonry
- Ist class K.B.Bricks
- Portland Cement of uniform consistency as men for construction with ferro cement.
- Sand as stated in case of ferrocement.
- Water as stated in case of ferro cement.
- Graphite-chips(optimal) 12mm to 20mm size.
Initially the model has been designed and tested for 2 cu.m.40 days hydraulic retention time(HRT)
- kilogram of fresh cattle dung produces 0.04 CuM of gas. Gas holding capacity of the plant is 50% of daily gas production capacity of plant.
- The digested slurry discharge opening into the pressure chamber is kept at a comfortable distance from the bottom portion of the gas outlet pipe of the plant.
- Structurally soound. Strength has been increased due to its spherical shape.
- Converse least surface area resulting in economy of construction material.
- Gas storage capacity of the daily gas production has been increased considerably.
- Can be constructed with all types of building materials utilized so far for construction of fixed dome biogas plants.
- The cost effectiveness as well as the efficiency is significantly noticed when constructed using ferrocement technology.
- Low consumption of cement which constitutes the main expensive item among the building materials.
- Low astatine period.
- Cost of labor and mason to construct Konark model has been reduced.
- Easy constructional procedure.
It goes without saying that Konark model is superior to all family-type fixed-dome models so far developed for production of biogas in respect of strength. Cost-effectiveness and gas storage capacity. With decreasing amount of fossil fuel, the renewable energy source is the only resort that mankind can bank upon. The days are notfar,when Konark model will evolve into a role model for biogas production. With the encouraging field results, this model will be useful for masses as-well-as classes.