Research of Efficient Burning of Bark and Wood Fuel

摘要

The efficient combustion of bark and wood fuel in the combustion furnaces of medium-pressure steam boilers “KM-75-40” and “Tampella-Carlson” which have worked more than 50 years were considered. The aim and objectives of the study were stated. Comprehensive energy survey of boilers was carried out when combustion of biofuel mixture with a moisture content of 56.7%, mass fraction of sawdust was about 42%. Components of the heat balance and emissions were determined. Ash particle size distribution for the content of combustibles was carried out. Porous structure of coke particles was studied using an Autosorb-iQ-MP automatic analyzer by nitrogen adsorption. Average diameter, specific surfaces and pore volumes were determined. It is shown that carbon particles carried away from the combustion chambers of boilers with the size of 0.25 mm and larger are a sorbent similar in properties to activated carbons. Therefore, it is advisable and technically possible to separate this fraction and then use it to clean wastewater and exhaust gases. State of the enclosing surfaces of the boilers was checked by thermovision inspection. Recommendations are elaborated to improve the energy and environmental performance of the surveyed boilers.