Measurement of particulate matter and trace elements from a coal-fired power plant with electrostatic precipitators equipped the low temperature economizer

The particulate matter and trace elements from a 660 MW coal-fired power plant boiler which equipped with a novel electrostatic precipitator were sampled and analyzed. To promote the thermal efficiency of power plants, a low temperature economizer was installed at the inlet of electrostatic precipitator to collect the heat generated from flue gas. The low temperature economizer can reduce flue gas temperature, and then affect the operation of electrostatic precipitator. Therefore, this experiment was carried out to investigate the collection characteristics of this novel electrostatic precipitator on particulate matter. In addition, the distribution of trace elements in solid combustion residues was also studied. The results indicate that the low temperature economizer can markedly decrease the amount of particulate matter at the outlet of electrostatic precipitator. The collection efficiency of electrostatic precipitator on particulate matter is significantly improved by the low temperature economizer, whereby the collection efficiencies of PM2.5 and PM1.0 can reach 99.7% and 99.2%, respectively. Most of the trace elements remain in the fly ash collected by the electrostatic precipitator, and less than 10% remain in the bottom ash, but very rare emit from the electrostatic precipitator. The low temperature economizer not only reduces the emission of particulate matter, but also diminishes the emissions of trace elements in flue gas. The enrichment characteristics of trace elements in submicron particles were also studied.