Low-rank high-volatile matter sub-bituminous coal grinding versus power plant performance

Abstract

The objective of this project was to determine if the power plant performance, characterized by megawatt and steam generation, is reduced when particle size distribution (PSD) of pulverized-coal fed into the burners is made slightly coarser. Tests were conducted in two phases at a Golden Valley Electric Association power plant. During the first phase, two tests were conducted at significantly different PSDs. Results indicated that coarser distribution did not hurt plant performance. Later, the second phase was carried out to test the repeatability of the observed combustion behavior as well as to test hypotheses on mill power consumption, emissions and unburned carbon. Unfortunately, the three tests in this phase did not result in statistically different PSD's, precluding any conclusions on the main objective. Therefore, further tests are needed to establish the effect of coarser PSD on power plant performance, emissions, unburned carbon and mill power consumption.