Influence of start-ups with fuel-oil on the operation of electrostatic precipitators in pulverised coal boilers

This article describes the results of a series of tests carried out in a pilot fly ash electrostatic precipitation facility operating with real gases from a 550 MWe pulverized coal-fired power station. The main goal of these tests was to determine the effects of boiler start-ups on the performance of the electrostatic preciptator. The tests were carried out during start-ups of the power station boiler. All tests were carried out with the same fuel. An evaluation was made of the effects of the use of fuel-oil as auxillary fuel in start-ups and shut-downs of the boiler, and different electrostatic precipitators operation procedures were tested during start-ups and shut-downs. The results of the experiments made it possible to assess the relative importance of different variables on the possible deterioration of the efficiency of the precipitators. Also evaluated were operational modes that have demonstrated an improvement in the performance of the precipitators after the transient stage of these operations. As a result of this study, a number of important operational recommendations are made on boiler start-up and shut-down procedures. (C) 2004 American Institute of Chemical Engineers Environ Prog, 23: 29-38, 2004.