BIOMASS & BIOGAS

CHAPTER 5Bio-mass Energy

Yogesh, Hiren, Missam Mechanical Dept. LJ Polytechnic

BiomassTerminology Biomass Energy =

energy recovered from biomass – organic matter such as plant material and animal waste

Biomass = recently living organisms

Fossil Fuels = partially decomposed ancient organisms Yogesh,Hiren,Missam Mechanical. LJ

Polytechnic

Fossil Fuel Formation

BiomassHistory Wood was the major fuel

source until the end of 19th century Today developing

countries use wood for ~35% of total energy supply

Early diesel engines were designed and tested to run on peanut oil

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BiomassBio Energy cycle

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BiomassBio Energy cycle on local scale

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Biomass Biomass Resources

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Biomass resourcesCorn

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Biomass ResourcesSoyabean

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Biomass ResourcesSorghum

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Biomass ResourcesSugar cane

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Biomass ResourcesSwitchgrass

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Biomass ResourcesWood chips and sawdust

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Biomass ResourcesSolid waste

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Creating Energy from BiomassBio Energy Conversion

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BiogasWhat is Biogas?

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Biogas is clean environment friendly fuel that

can be obtained by anaerobic digestion of animal residues and domestic and farm wastes, abundantly available in the countryside.

Biogas is an important renewable energy resource for rural areas in India

Biogas generally comprise of 55-65 % methane, 35-45 % carbon dioxide, 0.5-1.0 % hydrogen sulfide and traces of water vapor.

Average calorific value of biogas is 20 MJ/m3 (4713 kcal/m3).

Biogas

Yogesh,Hiren,Missam Mechanical. LJ Polytechnic

Biogas like Liquefied Petroleum Gas (LPG) cannot be liquefied under normal temperature and pressure.

Critical temperature required for liquefaction of methane is -82.1oC at 4.71MPa pressure, therefore use of biogas is limited nearby the biogas plant.

An estimate indicates that India has a potential of generating 6.38 X 1010 m3 of biogas from 980 million tones of cattle dung produced annually.

The heat value of this gas amounts to 1.3 X 1012 MJ. In addition, 350 million tones of manure would also produce along with biogas.

BiogasBiogas Production Process

Yogesh,Hiren,Missam Mechanical. LJ Polytechnic

Biogas production process (Anaerobic digestion) is a multiple-stage process in which some main stages are:

Chemical reactions involved in biogas production:

C6H12O6 → 3CO2 + 3CH4

CO2 + 4H2 > CH4 + 2H2O CH3COOH > CH4 + CO2

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Out let Pipe

In let Pipe

Digester

Drum

FLOATING DRUM TYPE BIOGAS PLANT

Gas outletInlet

Outlet

BiogasBio gas Plant

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BiogasBio gas construction

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BiogasDetailed Structure of biogas plant

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BiogasContribution of Biogas plant

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Better and cheaper fuel for cooking, lighting and power generation. Produces good quality enriched manure to improve spoil fertility. Effective and convenient way for sanitary disposal of human excreata, improving the hygienic conditions. Generate social benefits - reducing burden on forest, reduction in drudgery of women and children. As a smokeless domestic fuel it reduces the incidence of eye and lung diseases.