Biomass power generation

Biomass power generation is the power generation by utilizing the biomass energy that biomass has, which is a kind of renewable energy power generation, and its principle is mainly to convert the chemical energy in biomass into electricity, the specific process is as follows:
- **Biomass Pre-treatment**: usually biomass raw materials such as crop residues, forestry wastes, livestock and poultry manure, etc., need to be pre-treated. This may include operations such as crushing, shredding, and drying to adjust the particle size and moisture content of the biomass to make it more suitable for subsequent combustion or conversion processes. For example, straw may be cut into smaller pieces and then dried to reduce moisture content and improve combustion efficiency.
- **Combustion or conversion**
- **Direct Combustion for Power Generation**: Pretreated biomass is fully combusted in a boiler to produce high temperature and high pressure steam. When biomass is burned, the chemical energy stored within it is converted into thermal energy to heat water into steam. For example, in some large biomass power plants, large amounts of straw and other biomass are fed into specially designed boilers to be burned, producing high-temperature flue gases, which in turn heat the water in the boiler.
- **Gasification for Power Generation**: Biomass is incompletely combusted in a gasifier under oxygen-deficient conditions, where a thermochemical reaction occurs to produce combustible gases such as carbon monoxide, hydrogen, methane, and other gases, which are known as biomass gas. This process converts the chemical energy in the biomass into the chemical energy of the gas. For example, by controlling conditions such as temperature, pressure and air supply in the gasifier, the biomass undergoes a gasification reaction and the gas generated can be used as fuel for subsequent power generation.
- **Anaerobic fermentation for power generation**: Biomass is fermented using microorganisms under anaerobic conditions to produce biogas, the main components of which are methane and carbon dioxide. The organic matter in the biomass is decomposed and transformed by microorganisms to produce biogas, realizing the transformation from biomass chemical energy to biogas chemical energy. For example, in some biogas digesters in rural areas, livestock and poultry manure and crop residues are put into them, and biogas is produced after a period of fermentation.
- **Energy conversion**
- **Steam Turbine Power Generation**: High-temperature and high-pressure steam produced by combustion pushes the steam turbine to rotate, and the thermal energy of the steam is converted into the mechanical energy of the steam turbine. The steam turbine is connected to the rotating shaft of the generator, and the rotation of the steam turbine drives the coil inside the generator to do cutting magnetic flux movement in the magnetic field, thus generating electric energy and realizing the conversion from mechanical energy to electric energy. This method is similar to traditional thermal power generation, except that the fuel is switched from fossil fuels such as coal to biomass.
- **Internal Combustion Engine Power Generation**: Biomass gas or biogas can be used as fuel for internal combustion engines. The gas is burned in the cylinder, generating a high temperature and high pressure gas that pushes the piston to do the work, rotating the crankshaft of the internal combustion engine and driving the generator to generate electricity. The internal combustion engine power generation has high flexibility and efficiency, which is suitable for some small biomass power generation projects.
- **Fuel cell power generation**: For some purified high-quality biogas or biomass gas, fuel cell technology can be used to generate electricity. Fuel cells convert the chemical energy in the gas directly into electricity through electrochemical reaction, which has high power generation efficiency and low pollutant emission. However, fuel cell technology is currently costly and has not yet been applied on a large scale to biomass power generation.

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