PRODUCTION OF SOLID BIOFUELS FROM GRAIN PROCESSING WASTES

Abstract

The article is devoted to the issues of solid biofuel production. The classification of biomass used in the production of solid biofuels by origin is given. The main types of grain waste in the southern region for the production of solid biofuels are identified. The article analyzes the soybean market in the world and Ukraine, shows the trend of growing soybean production, which is caused by the growing demand for food and feed purposes. Soybean yield indicators in Ukraine are analyzed and it is found that Kherson region is one of the leaders of soybean yields for 2019. It is shown that in soybean cultivation in Ukraine a considerable amount of secondary resource is obtained - straw, as a by-product of crop production. It is established that the average yield of rice of Kherson region prevails in Ukraine, a large amount of rice husk is formed during processing of raw rice. Physico-mechanical properties of rice husk and soybean straw have been determined. The possibility of production of fuel briquettes from the waste was considered, technological scheme of production of fuel briquettes from waste, which are formed at the enterprises of processing industry and by-products of crop production is given. The technology of production of fuel briquettes from soy straw and rice husk was introduced at the enterprise of Kherson region, which is engaged in cultivation and processing of soybeans and rice. Quality indicators of fuel briquettes were determined: humidity, ash, sulfur, carbon content, volatile matter yield and specific combustion heat. It is established that the quality of fuel pellets is significantly influenced by humidity, degree of grinding and physical and chemical properties of raw materials. When the moisture content of raw materials more than 14% decreases the density of the granules and, due to the evaporation of moisture, cracks appear in the granules, which reduce their strength. With the reduction of the average particle size of the biomass to 2 mm, the quality of the fuel products increases, but the fine fraction of the biomass of the matrix is erased. The heat of combustion of the obtained solid briquettes exceeds the normative values of European standards at a level not lower than 18 MJ / kg. Ash content (0.5 %), normalized by European standards, is practically unavailable for Ukrainian producers, fuel briquettes made from soy straw and husks have higher normalized ash values in accordance with 7.0 and 14.0 %, which reduces their quality indicators.

Keywords

• waste,
• rice husk,
• soybean straw,
• technology,
• biofuels,
• briquettes,
• quality.