Biomass energy technology mainly includes gasification, direct combustion power generation, solidification casting and liquefaction. At present, the first three technologies have reached a relatively mature commercialization stage, while biomass liquefaction is still in the research, development and demonstration stage. In terms of products, biomass liquefaction can be divided into liquid fuel production (ethanol, bio-oil, etc.) and chemical production. Since the preparation of chemicals requires a relatively complex product separation and purification process, with high technical requirements and high costs, it is still in the laboratory research stage at home and abroad. The high temperature flue gas quickly heats and decomposes the biomass, with a temperature ofreaction of 600°C.
Raw materials for fuel ethanol biomass production mainly include surplus grain, energy crops and crop straw. The production of ethanol from starchy feedstocks such as cereals is a mature traditional technology. Although the cost of producing fuel ethanol from grain is high and the price is not competitive with petroleum fuels, grain harvests sometimes increase from year to year and a large amount of grain aged accumulates. Fuel ethanol can be added to gasoline in a certain proportion as vehicle fuel. The use of ethanol fuel at home and abroad has proven that it can keep the engine in good technical condition, improve bad emissions and have obvious environmental benefits. However, even if the remaining 30 million tonnes of cerealstes in China during the bumper harvest are converted into ethanol, 10 million tons of ethanol can be produced, which is only 1/10 of the crude oil deficit in 2000 and as China's population continues; to grow, it is difficult to find food. A significant surplus appears. Therefore, aged grains are an unreliable source of energy.