Converting Waste Agricultural Biomass into a Resource - UNEP

Biomass Gasifier 97
India, Pilot Demonstration
Crop
Residue
Process
Equipment
Main Product
Eucalyptus, Pongamia, Suvery, Neem, Coconut
Fronds, Sababul
Crop residues
Gasification
Gasifier with 100% producer gas engine
Producer gas
Technical Description of Technology
250 kwe biomass gasifier at Adichunchangiri Institute of Medical Science,
Balagangadharanatha Nagar, Bellur Cross, Nagamangala Taluk, Mandya
District, India.
Capacity : 250 Kwe
Gross Output : 250Kwe
Net Output : 220 Kwe
Continuous output : 205 Kwe
Technology : Gasifier With 100% producer gas engine
Biomass required : 5300 Kg per day
Units generated : 3840 units per day
Biomass consumption per unit : 1.4 Kg
No of labours employed: 20 (direct employment
Indirect employment : 100 ( for collection ,transportation of biomass )
Cost of the plant : Rs 69.52 lakhs
Subsidy from MNES : Rs 37.5 lakhs
Detailed Process Description
The biomass gasifier is essentially a chemical reactor where various complex
physical and chemical processes take place. Four distinct processes take
place in a gasifier, namely drying of the fuel (woody biomass), pyrolysis,
combustion and reduction. Biomass is fed into gasifier at regular intervals.
The equipment is designed in such a way that it takes air in controlled
quantities, resulting in partial oxidation of biomass into producer gas. One Kg
of biomass gets converted into 2.5 to 3.0 Nm 3 of gas with a calorific value of
1000-1300 Kcal per Nm 3 , which would have the following composition. CO-
15-20% CH 4 - 1-4% Co 2 -8-5%, N 2 –45-55%. The gas coming out of the
gasifier is hot (200-250 0 C) and contains some contaminants, particulates and
volatiles, which needs to be cooled and cleaned before feeding into the
generators. The cooling cleaning system consists of scrubbers and
associated accessories. Cold clean gas produced is fed to engine along with
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