In GP Gasifiers, solid biomass, a carbonaceous fuel is burnt under controlled air and water in the Gasifier reactor to produce a combustible (carbon–monoxide based) gas, generally known as producer gas. This gas having calorific value of 1200–1350 Kcal/Nm3 can be used for generation of electrical power and/or thermal energy. However, before this gas is used, it is important to clean and cool it as it contains tar and other impurities, for which an elaborate gas cleaning and cooling system is provided. The capacity of such plants ranges from 10kW to 1MW. Systems are designed for cogeneration in the industries based on specific requirement of the clients. Higher capacities can be achieved by incorporating multiple systems.
Since producer gas is combustible in nature, the same can be fired with the help of a suitably designed burner. Boilers, furnaces, ovens etc can then be gas fired to replace furnace oil, LPG, HSD, CNG, coal or any other costly fossil fuels. In this case, there will be no ash/fly ash or particulate in the exhaust gas.
Again, temperature up to 1000 0 C can be achieved by burning the above gas. Hence, process heat for industrial applications namely, heating of water, air, fluid etc. is obtained from producer gas.
Electrical Power :
GP Biomass Gasifier Plant is highly suitable as a decentralized power station– both for captive use in the industries as well as for rural electrification, where transmission of power through grid line is very expensive and electrical load growth is minimal.
For generation of electrical power with producer gas, two types of engines can be used : -
Dual Fuel Engine: A dual fuel engine is basically a diesel engine with conversion kit to run the engine with diesel and any suitable gas having certain calorific value including producer gas. This works on the diesel cycle. Producer gas is added to the air, which is introduced to the engine before introducing it into the turbocharger. This mixture of air and gas is compressed in the cylinder just as air is compressed in normal CI engine. After compression, the diesel is injected through a conventional fuel system. This diesel oil ignites first as pilot fuel and the heat released by its combustion leads to the combustion of the gas air mixture. In the process, consumption of diesel can be reduced to the extent of 65%-75%. Existing engine may also be retrofitted for dual-fuel operation.
Spark Ignition Engine : The producer gas is the sole fuel in the Spark Ignition( SI) engine. A gas carburetor or mixer is used to prepare the air- gas mixture. The mixture is sucked into the engine during the suction stroke, compressed and then ignited by a spark from a spark plug in the cylinder head.