FEATURES AND EXPERIENCE OF CONVERTING GAS-OIL BOILERS OF INDUSTRIAL CHP PLANTS TO BURNING BIOMASS AND SUB-BITUMINOUS COAL

Abstract

The paper examines the features of biomass as a fuel and substantiates that for agrobiomass waste with a high content of alkali metal oxides and slag properties of ash, it is more appropriate to burn it in a dense bed in the form of pellets, which ensures a temperature at the exit from the furnace of no more than 900 °C, a low part of fly ash and low content of unburned carbon in it, and so eliminates the risk of smoldering deposits with their melting and slagging. Technical solutions are given and the experience is presented of gas and oil boilers of CHP plants of sugar factories reconstruction with their transfer to the burning of biomass and/or coal in a dense bed on a direct-flow grate with the replacement of the air heater with air-water heater, with the addition of stages of the boiling economizer to compensate for the decrease in the heat perception of the furnace screens, maintaining the overall height of the boiler and the plane of the boiler cell. The reconstruction of boilers according to the developed technical solutions is possible to perform in the interval between production seasons, its implementation on boilers BKZ-75 GMA of Radekhiv and Chortkiv sugar factories allowed to achieve acceptable technical, economic and environmental indicators and ensured payback due to the difference in commercial prices of gas and of agrobiomass pellets. It is proposed to replicate the positive experience in the creation of decentralized regulating thermal generation capacities of the country. Bibl. 30, Fig. 3, Tab. 4.