Effect of Flue Gas Composition on Mercury Removal by Injecting Rice Husk-Derived Activated Carbon

doi:10.11930/j.issn.1004-9649.201901022

Abstract

Abstract: The flue gas mercury removal experiment was carried out on a 0.3MW pilot scale circulating fluidized bed test facility by injecting biomass based activated carbon which is originally derived from rice husk and then modified by halogenated ammonium. Effects of exit temperature of the SCR and flue gas, concentration of SO₂ and NO on the injection demercuration efficiency were discussed. The ASTM Standard D 6784-02 (OHM Ontario Method) was applied to measure the concentration of mercury from the coal-fired flue gas. The results showed that both the mercury removal efficiency and elemental mercury conversion efficiency go up with the elevated flue gas temperature; The existence of NO can enhance the mercury removal effect but SO₂ will inhibit it on the other way. The mercury removal efficiency could reach about 90% with this modified type of activated carbon sprayed into flue gas under the conditions of SCR inlet temperature in the range of 351~370℃, flue gas temperature in the range of 191~210℃, SO₂ volume fraction of (293~602)×10^-6, NO volume fraction of (588~893)×10^-6, activated carbon injection quantity of 0.5 kg/h, reaction space velocity of 4 000 h^-1, and flue gas flow rate of 400~500 m³/h.

Key words: coal fired flue gas, injection demercuration, NH₄Br modification, rice husk-derived activated carbon, flue gas composition

CLC Number:

TAO Jun, GU Xiaobing, HUANG Tianfang, LIU Shuai, HU Peng, DONG Lu, HUANG Yaji, DUAN Yufeng. Effect of Flue Gas Composition on Mercury Removal by Injecting Rice Husk-Derived Activated Carbon[J]. Electric Power, 2019, 52(10): 150-154,184.

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URL: https://www.electricpower.com.cn/EN/10.11930/j.issn.1004-9649.201901022

https://www.electricpower.com.cn/EN/Y2019/V52/I10/150

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