Power Plant Engineering

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.
W a ste
B io g a s P lan t
B io g a s
S lu g e M a n u re
The cultivated or harvested biomass is specially grown on land or in sea/lake for obtaining raw
materials for biogas production.

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POWER PLANT ENGINEERING