RELEVANCE OF USING MISCANTUS AS BIOMASS FOR BURNING IN SOLID FUEL BOILERS

Abstract

The purpose of the research is to evaluate the relevance of using miscanthus energy culture as biomass for burning in solid fuel boilers. Research methods. Analytical studies on the relevance of the use of energy culture of miscanthus as biomass for burning in solid fuel boilers were carried out by processing the available scientific and informational reports. Research results. For the production of biomass, special energy crops are used, which are characterized by rapid growth of technological mass - willow, poplar, sycamore, or certain varieties of herbaceous plants (miscanthus, millet, sorghum, etc.). Energy crops are plants that are specially grown for use directly as fuel or for biofuel production. After a single planting, the crop (miscanthus) can be harvested annually for 15 years or more with an average yield of 10 t/ha. Miscanthus has a well-developed root system (2,5 m deep), is characterized by rapid growth and resistance to low temperatures. Technological options for biomass combustion are divided into three main types: combustion in a layer, dust combustion, combustion in a pseudo-liquefied state, as well as a combined type - combined combustion of biomass with other fuels. Miscanthus is characterized by a fairly high level of energy production, and actually 143-560 GJ/ha, energy yield is 360 GJ/ha/year. Increasing the use of perennial energy crops such as miscanthus helps reduce fossil fuel consumption. In addition to high yields, drought resistance, maintaining soil structure, reducing the risk of soil erosion, improving soil organic matter and other important agronomic indicators, miscanthus has a high resource energy efficiency, which can be 90 %, a high level of conversion. With a yield of 8-17 t/ha/year, the selling price of miscanthus during its processing into thermal energy and biological oil of rapid pyrolysis was received at almost the same level - 100 €/t. The calorific value of energy culture is 17,7 MJ/kg, according to other scientific data is in the range of 16,0-17,2 MJ/kg, according to regulatory requirements CEN / TC 14961: 2005 – 18,4 MJ/kg, despite some deviations from the standards, miscanthus can be described as a valuable energy raw material suitable for combustion in boilers. Conclusions. According to the results of analytical studies, the relevance of using miscanthus energy culture as biomass for combustion in solid fuel boilers was assessed for the first time. Energy crops (miscanthus) after a single planting can be harvested annually for 15 years or more. Miscanthus is characterized by a high level of energy production, namely 143-560 GJ/ha, energy yield is 360 GJ/ha/year. Increasing the use of perennial energy crops such as miscanthus helps reduce fossil fuel consumption. Miscanthus has a high resource energy efficiency, which can be 75-90 %, a high level of conversion. According to scientific reports, the calorific value of energy crop (miscanthus) is 17,7 MJ/kg, according to regulatory requirements CEN / TC 14961: 2005 – 18,4 MJ/kg, despite some deviations from the standards, miscanthus is characterized as a valuable energy raw materials effective during combustion in solid fuel boilers. Key words: biomass, renewable energy sources, energy efficiency, energy crops, miscanthus, solid fuel boilers.