Abstract: The technology of multi-pollutants synergistic removal in coal-fired power plants will become the research hotspots in the future. In this paper, a new device named wet phase transition agglomerator (WPTA) is designed and developed to achieve the goal of removing fine particles and multi-pollutants collaboratively from high temperature wet flue gas. Verified through lab-scale testing, pilot-scale testing and a full-scale onsite test under working conditions in a 660-MW lignite-fired power plant, this device has exhibited excellent performance in fine particle and multi-pollutant removal. The pilot-scale test indicates that after the flue gas flow passed through the WPTA, the volume fraction of particles changes from unimodal distribution into bimodal distribution. The peak value of the particle volume fraction is decreased substantially for the particle around 2μm while that of the particles over 10μm tends to increase. The full-scale test shows that the removal efficiency of PM_2.5 and PM_1.0 is improved by 5 and 15 percentage points respectively at full generation loading. The efficient removal of trace elements of Hg, Ba, Ga, As, Li, Mn, Sr and Ti is also achieved simultaneously, of which the removal efficiencies of Hg and As are improved by 4.18 and 2.82 times, respectively. The study result indicates that the new configuration of WPTA+WESP can meet the requirements for ultra-low emission standards on fine particulate matters and other pollutants for coal-fired power plants of China.

Key words: WPTA, coal-fired power plant, dust, fine particulate matter, synergistic removal, multi-pollutants