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| Biomass Gasification |
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| Versatile source of energy |
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. Biomass, for the purpose of gasification,
refers to natural resources such as prosopsis juliflora, casuarina
or any other type of woody biomass. Agricultural waste such
as coconut shell, coconut fronds etc. can be used in their normal
form. Other powdery waste such as groundnut shell, saw dust,
rice husk etc can also be used in briquetted form.
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| Gasification is the process
that allows partial pyrolysis of biomass under controlled conditions
leading to generation of “Producer Gas”. Producer
gas is essentially composed of Carbon Monoxide (CO) 18-20%,
Hydrogen (H2) 18- 20%, Methane (CH4) 3-4%, Carbon di oxide 9-12%
and the balance nitrogen. The flammable and useful components
in this gas are CO, H2, CH4. The gas has a calorific value of
1100 Kcal/ Nm3. This gas after being put through a series of
cleaning processes, is used to run an engine for power generation,
or be used in replacing costly and polluting fossil fuels in
furnaces, kilns etc. for thermal applications. |
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| Versatile Applications |
Producer gas generated from gasification
can be put to a variety of uses, as under: |
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Thermal Heat |
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Power Generation |
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Combination of Heat and Power |
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| Thermal Applications |
Broadly 3.5 kg of Biomass is
required in the place of 1 litre of Fossil Fuel oil. Each Kg
of Biomass generates 2-2.5 M3 of Producer Gas. Thermal energy
of 1100 to 1200 Kcal/M3 is released. Flame Temperature up to
1200oC is capable of being achieved, with optimal
premixing air with gas. Devices such as Furnaces, Hot Air Dryers,
Kilns, Boilers and Thermic Fluid Heaters can be retrofitted,
for cost effective generation of Thermal Energy. |
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| Power Generation |
Producer Gas is used for Power
Generation in two ways:
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DUAL FUEL MODE and |
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100% GAS ENGINES |
In the former, Gasifier is retrofitted to existing Diesel/Furnace
oil Generators replacing fossil fuel to the extent of 75%
to 80%. For each Unit of Electricity, 0.90 Kg of Biomass and
80ml of fossil fuel are required.
In the latter, use of fossil fuel is completely eliminated
with Producer Gas used in Spark Ignited gas engines. Each
Unit of Electricity normally requires 1.2 kg of Biomass. Delivered
cost of electricity in both methods is quite low compared
to the prevalent power tariff in most states. |
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| By-products |
Where coconut shell is
used as the feed stock the by-product obtained is activated
carbon which is a valuable product in itself. In case
of briquetted rice husk, the ash obtained can be further
processed to obtain precipitated silica. Char obtained
while using any other woody biomass is also a saleable
commodity fetching remunerative prices as it has a high
fixed carbon content. |
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| Renewable Sources Of
Energy- Why biomass gasification? |
With the compulsive
need to conserve fossil fuels, which is also becoming uneconomic,
man’s inventive genius has now turned to Renewable Sources
of Energy- Water, Wind, Waves, solar and Biomass. While Power
generation from Hydel projects is inconsistent due to persistent
monsoon failures, wind Energy has several shortcomings, on
account of geographical factors. Waves also have similar limitations.
Solar energy can be tapped only during day time and is seasonal,
While all these Renewable sources are not without merit and
they have given the much needed respite from dependence on
fossil fuels, they lack the versatility of BIOMASS |
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| Biomass |
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As a source of fuel, with unique advantages, Renewable Biomass offers the most viable option |
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| PARAMETERS |
WIND |
HYDEL |
SOLAR |
BIOMASS |
| Feedstock Availability
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Seasonal |
Fluctuating / Seasonal |
Limited to daytime |
In abundance |
| Location |
Geographical constraints
(only in windy areas)
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Geographical constraints
(only on rivers, rivulets) areas Limited |
Limited to sunny areas |
Any where
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| Cost of Fuel |
Nil |
Nil |
Nil |
Low |
| Capital Cost |
High |
High |
Very High |
Moderate |
| By Products |
Nil |
Nil |
Nil |
Wood charcoal Activated
Carbon |
| Plant Load Factor |
Low |
Low |
Low |
High |
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