The application of biomass wood pellete fuel is mainly through the high-temperature mode of a special biomass boiler, and Kingwood summarized the following characteristics of biomass fuel:
1. It belongs to high volatile matter, low carbonization degree and oxygenated material. The volatile content is as high as 75%-85% on average, which is very favorable for fuel combustion. The carbon content is only 37% on average, but the fixed carbon content is a symbol. The average degree of charring is 17%, but the average calorific value is as high as 36%. This means that the fixed charcoal with only one sixth of the combustible content accounts for one-third of the calorific value, and the average oxygen content is as high as 33.18%. .
2. The content of flammable decomposition products is high, and the thermal decomposition products of cellulose and hemicellulose of 75% straw form volatiles. The main components are heavy molecules such as tar and acid, which exist in the gaseous state in the hot state. When the temperature is higher than 600°C, a cracking reaction occurs to generate a part of combustible gas. Thus, the molecular weight of the wood tar, wood vinegar, and wood acid in the combustible gas is reduced, and the heavier molecules of alkene, alkene, and benzene become fuel. Combustible ingredients participate in combustion.
3. The range of fuel moisture changes is relatively large, generally between 5% and 60%.
4. The increase of latent heat of cellulose in biomass, the thermal decomposition product of cellulose, tar, wood vinegar, and the weight fraction of benzene and alkanes heavy molecules are 15%-20%. Under high-temperature conditions, heavy molecular cracking and combustion Can release energy.
5. There are many types of straw ash compounds produced by combustion. The ash content of biomass varies with the type of the biomass and the place of production, and is affected by the planting conditions. The contents of the ash vary.