Biomass has several attractive features, which make it an ideal and automatic choice of energy fuel especially for HT Consumers, with plans for Captive Power Generation. Besides being abundantly available, biomass can be found uniformly throughout the year in all seasons. Although biomass in solid form has been used from time immemorial, largely for purposes of cooking and space heating, only in recent times Gasification Technology has been developed.
Gasification is the process of converting solid Biomass into gaseous fuel. The process involves partial pyrolysis, oxidation and reduction under sub-stoichiometric conditions. This generates producer gas, which contains H2, CO, CH4, CO2 and N2. Raw and hot producer gas contains particles of dust and condensable compounds, termed tar, both of which should be restricted to less than 50 ppm each, for the gas to be used for internal combustion engine. Producer gas has to be cleaned and cooled to ambient temperature for meeting Thermal needs and Power generation.
Plant Configuration
Biomass Gasifiers are designed to use a wide range of Biomass - Wood or Agro residues in briquetted form. Gasifier Plant consists of:
  • Material handling system for conveying biomass into the Reactor
  • Gasifier Reactor , which generates producer gas.
  • Cooling, Scrubbing and cleaning system, which help to clean and cool the producer gas to ambient    temperature, prior to admission into Burners for Thermal application or into IC engines for power    generation. Cooling water can be recycled and used after chemical treatment.
    • Technology:
    The technology is from Indian Institute of Science, Bangalore and wholly indigenous with the following salient features :
  • Open top, twin air entry system, which ensures a better thermal environment compared to the    conventional closed top model.
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  • Multi-fuel capability – wood residues and agro residues in briquetted form with moisture content less    than 10%.
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  • Permits high gasification efficiency above 85%, with biomass consumption between 0.8 kg to 1.2    kg/KWH
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  • Producer gas generated is of a very high quality.
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  • It is environmentally sound with low Nox in the engine exhaust
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  • The gasifier is robust in construction with ceramic lining inside which provides a better operating    atmosphere and considerably reduces gasifier maintenance.
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  • In-built safety features which isolate the gasifier in case of an emergency shut down.
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  • Patented gas cleaning system which provides gas with less than 15 ppm of suspended matter thereby    meeting the quality standards set by engine manufacturers
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  • Plants of capacity as low as 10kW right up to MW levels are all viable
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  • Eligible for benefits under CDM
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    By-products
    Biomass such as Coconut Shell, Rice husk offers scope for generation of by products such as Activated carbon, Precipitated Silica, which fetch remunerative prices.
    Versatile Applications
    Producer gas generated from gasification can be put to a variety of uses, as under:
  • Thermal - Heat
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  • Power Generation
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  • Combination of Heat and Power
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    Examples of Gasifier based Plants for Power Generation and thermal application:
  • Aluminium Melting
  • Biscuit making furnace
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  • Metal heat treatment
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  • Crumb rubber preparation
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  • Hot air generators
  • Fluidized bed driers
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  • Rotary kiln for sand drying in recovery of beach minerals
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  • Captive power
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  • IPP and grid linked power
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  • Village electrification
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     Biomass Gasification
     Biomethanation
     Clean Development Mechanism (CDM)