Prospect of biomass pellet fuels
From the perspective of policy, the law on renewable energy of the People's Republic of China clearly requires that the development of biomass energy and biomass products can be subsidized by local governments and tax deductible.The national development and reform commission, ministry of agriculture in order to accelerate the comprehensive utilization of straw, straw resource and commercialization, promote resource conservation, environmental protection and increasing farmers' income, on February 9, 2009, established the formulation of comprehensive utilization of straw planning guidance, puts forward to comprehensive utilization of straw by 2015 more than 80%, increase the use of straw is the inevitable choice of agriculture and energy development.
For the raw materials, the capacity of straw can be up to seven billion each year. Large quantity and many kinds of agriculture, forestry and waste, wide distribution, but recycling utilization rate is low, has not been fully used, not only wastes the resources, and easy to cause pollution of the environment, even fire, the threat to the forest, the threat to the safety transportation.
Look from the characteristics of straw pellet fuel has the following several aspects: (1) using the waste in the process of production in agriculture and forestry (crops straw, rice husk, peanut shell, corn cob, sawdust, branches, leaves, wood scrap, etc.) as raw materials, environmental protection and energy saving, good safety, fire prevention. High density, long burning time.The grain fuel volume was reduced by 4 ~ 6 times, which greatly extended the burning time of straw. It is convenient to burn, store and transport. The fuel diameter is generally 4mm, 6mm and 8mm, and the length is 10 ~ 20mm, the moisture is not greater than 10%, the density is not less than 1100kg/m3, the ash content is not more than 0.9%, and the calorific value is not less than 14650,000j.
From the point of view of application, biomass pellet fuel can be used to replace firewood, liquefied gas and so on. It can be widely used in biomass straw power plant, boiler in enterprises and institutions, biomass straw gasification station, household gasifier, European heating fireplace and so on.
Biomass pellet fuel production process
The production process of biomass pellet fuel is as follows: raw material recovery and pulverization (powder length less than 5 mm) and tempering (moisture content is not more than 15mm), pressing molding, cooling, drying, packing and transportation.
Premise of biomass pellet material molding
The larger the unit density of crushing material, the better
The higher the unit density of the crushing material, the better the self-flow, the higher the grain yield. The crop straw is best to break into grain shape with the grinder. Crushed raw materials with kneading machine can be used to crush the raw material, which is easy to be put into the air, and the feeding performance is not good, and the grain yield is low.
The moisture content of the material should be suitable
Material moisture content is too high or too low, will affect the grain yield and quality. If the moisture content of the material is too high, more than 20%, it is difficult to adjust the material. It is easy to cause the material to slip between the inner wall of the ring mould and the pressure roller, causing the ring die hole to be blocked, the particles can not be pressed, and the output is reduced. It is also prone to fattening, low density, poor finish, and low quality. If the moisture content is less than 14%, the material and machine will rub vigorously, produce the powder and reduce the grain production. Generally, the moisture of the material should be 15% ~ 18%.