Mercury and other trace elements removal characteristics of DC and pulse energized electrostatic precipitator

Removal of zinc rich ash and mercury from gas stream using electrostatic precipitators has been investigated. Dust particles collected from Mastsuyama municipal incineration plant thermal plasma ash volume reduction system were used to study the performance of ESP to collect zinc rich ash. The ash was analyzed by neutron activation analysis (NAA) using the McMaster Nuclear Reactor. Collection efficiency as high as 99.9% was obtained in the removal of Zn from the flue gas with DC energization of the ESP. The mercury concentration was measured using a cold vapor atomic absorption spectrometer (CV-AAS) after sampling (OSHA-140 method) from the flue gas stream. As a function of concentration, the mercury collection efficiency was higher at higher concentration of mercury. Higher collection efficiency was obtained under negative DC energization compared to other modes of energization of the ESP; however, power consumption under pulse application was much smaller compared to DC energization.