Power Plant Engineering

NON-CONVENTIONAL ENERGY RESOURCES AND UTILISATION 55

2.14.2 Raw Materials

All types of organic wastes which can form slurry are suitable for producing biogas by the
process of anaerobic digestion in a biogas plant. Wood and sugar biogases are difficult and time con-
suming with this process and incineration may be preferred. The choice of raw material (in feed) is
based on availability of the waste. The biogas plant is designed to suit particular type of in feed.

Dung Water

Biogas

Plant

Biogas

Methane

Sludge

to

Manure

Domestic

Cooking

Fuel for

Kilns and

Furnaces

Fuel for

IC Engine

IC Engine

Driven

Generator

Lighting

Fig. 2.2. Energy Route of Biogas (Gobar Gas).
Biogas production taken different time period depending upon raw material; temperature; proc-
ess adopted etc.

The biomass used as a raw material can be classified into the following categories.
Waste Cultivated and Harvested
Agricultural wastes Agricultural energy crops
Rural animal wastes Aquatic crops
Poultry waste
Butchary waste
Urban waste (garbage) Forest crops
Aquatic wastes
Forest wastes
coconut husk waste
Industrial wastes
Others are poultry waste, piggery waste, sheep, goat, cow, horse dung, Slaughter house waste,
coconut shell, husk ,waste garbage, fruit skins and leftovers.
The waste is generated periodically and can be converted into useful biogas. The problem of
waste disposal is solved as the sludge is used as manure.

Waste Biogas Plant Biogas

Sluge M anure

The cultivated or harvested biomass is specially grown on land or in sea/lake for obtaining raw
materials for biogas production.