Biomass gasifier

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A biomass gasification furnace is the main equipment for biomass gasification. Here, biomass is converted into combustible gases through combustion and gasification. Gasifiers are divided into fixed-bed gasifiers, fluidized-bed gasifiers, and entrained-bed gasifiers. 　　Fixed-bed gasifier Fixed-bed gasifiers can be classified into downward suction type, upward suction type, lateral suction type, and open-type gasifiers. The downward-flow fixed-bed gasifier is characterized by the mixed downward flow of gas and biomass material. Through the high-temperature throat area (only the down-suction type is equipped with a throat area). Biomass undergoes gasification in the throat region, and tar can also be pyrolyzed on a charcoal bed. Generally, a downward-flow fixed-bed gasifier is not equipped with a grate, but one can be installed if the size of the feed material is small. This type of gasifier has a simple structure and operates reliably; it is suitable for relatively dry bulk materials, or mixtures of high-volume materials with low ash content along with a small amount of coarse particles. Its maximum processing capacity is 500 kg/h. Some in Europe are currently **in use for commercial operations. 　　The upward-flow fixed-bed gasifier is characterized by the gas flow direction being opposite to the material movement direction. The biomass feedstock flowing downward is dried and pyrolyzed by the hot gas flowing upward. At the bottom of the gas furnace, fixed carbon undergoes incomplete combustion and gasification with the oxygen in the air, producing combustible gases. The thermal efficiency of upward-flow fixed-bed gasifiers is higher than that of other fixed-bed gasifiers. Moreover, the requirements for raw materials are not very strict. Although there are no larger sizes available at the moment, in principle its capacity is unlimited. This type of gasifier is mainly used in Europe and some countries in Southeast Asia. 　　The horizontal suction fixed-bed gasifier is characterized by air being supplied from the side, and the output gas flowing out from the side. The gas flow passes transversely through the combustion gasification zone. It is mainly used for charcoal gasification. It is widely used and in commercial operation in South America. 　　The happy-type fixed-bed furnace is similar to the downward suction type, with the gas flow moving downward together with the material. However, the throat area has been replaced by a rotating grate. The main reaction takes place in the combustion zone above the grate. It has a simple structure and reliable operation. It was developed in our country and is mainly used for rice husk gasification; it has been in commercial operation for many years.