Pollution Research Paper

EXAMINATION OF COMBUSTION PROCESS OF HARD COAL AND PREDRIED LIGNITE BLENDS

AMIT ARORA, HALINA PAWLAK-KRUCZEK, MARCIN BARANOWSKI, MARCIN DEBOWSKI,KRYSTIAN KROCHMALNY, LUKASZ NIEDZWIECKI AND JAKUB MULARSKI

Abstract

The paper focuses on investigations of co-firing of the predried lignite with hard coal at different share of lignite in laboratory scale iso thermal flow reactor. The objective of the research was to determine the effect of different share of lignite on burnout, emission and ash properties of total mixture of fuels. During the testes five fuels where ex animated Hard Coal Janina IV, Lignite Sieniawa, Blend 10 (90% Janina IV + 10% Sieniawa), Blend 30 (70% Janina IV + 30% Sieniawa),Blend 50 (50% Janina IV + 50% Sieniawa) (share by mass). Laboratory tests of pulverized coal and its blend were carried out on iso thermal flow reactor included examination of O2, CO, CO2, NOx,SO2 emissions and the temperature distribution. All the data were continuously recorded, with 1 second interval. Also the characteristics of both hard and brown coal were carried out, which includes proximate and ultimate analysis. The wall temperature of reactor was kept at 1200°C during all tests and the total flow air flow air was kept at 4 m-3•hr-1, while the flow of pulverized coal was changed resulting changing the excess air. The mean value of temperature in axis of iso thermal flow reactor was similar for all coals and its blends and gas emissions generally was lower for blends. Averages values were calculated from data obtained from ongoing for about 1 hour combustion process under steady state conditions. The results of studies have demonstrated positive effect of the content of pre-dried lignite on combustion stability including the degree of burn-out which at combustion of all blends was two times lower than for hard coal.