[1] Zhao Shilin, Duan Yufeng, Zhou QiangZhu Chun, She Min, et al. Experimental studies on gas-phase mercury oxidation removaland denitration of coal combustion with NH4Br addition [J]. Journal of Southeast University (English Edition), 2015, 31 (2): 226-231. [doi:10.3969/j.issn.1003-7985.2015.02.012]

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Experimental studies on gas-phase mercury oxidation removaland denitration of coal combustion with NH₄Br addition()

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Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

Volumn:

31

Issue:

2015 2

Page:

226-231

Research Field:

Energy and Power Engineering

Publishing date:

2015-06-20

Info

Title:

Experimental studies on gas-phase mercury oxidation removaland denitration of coal combustion with NH₄Br addition

Author(s):

Zhao Shilin;  Duan Yufeng;  Zhou QiangZhu Chun;  She Min;  Lü Jianhong

Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, Southeast University, Nanjing 210096, China
School of Energy and Environment, Southeast University, Nanjing 210096, China

Keywords:

coal additives;  NH₄Br;  mercury oxidation;  mercury removal;  synergistic denitration

PACS:

TK16

DOI:

10.3969/j.issn.1003-7985.2015.02.012

Abstract:

In order to remove gas-phase mercury and NO_xx from flue gas, experimental studies on flue gas mercury oxidation removal and denitration of Guizhou anthracite combustion with NH₄Br addition were carried out. The influence of NH₄Br addition on the ignition temperature and combustion characteristics was studied using a thermogravimetric analyzer. The effects of the NH₄Br addition amount on gas-phase mercury oxidation and removal were investigated in a bench scale of 6 kW fluidized bed combustor(FBC). Mercury concentrations in flue gas were determined by the Ontario hydro method(OHM)and the mercury mass balance was obtained. Results show that the NH₄Br addition has little influence on the ignition temperature of Guizhou anthracite. With the mercury mass balance of 95.47%, the proportion of particulate mercury Hg^p, gaseous mercury Hg⁰ and Hg²⁺ are 75.28%, 11.60% and 13.12%, respectively, as raw coal combustion. The high particulate mercury Hg^p in flue gas is caused by the high unburned carbon content in fly ash. When the NH₄Br addition amount increases from 0 to 0.3%, the concentration of gaseous Hg⁰ and Hg²⁺ in flue gas decreases continuously, leading to the Hg^p increase accordingly. The oxidation rate of Hg⁰ is positively correlated to the Br addition amount. It demonstrates that coal combustion with NH₄Br addition can promote Hg⁰ oxidation and removal. NO_xx concentration in flue gas exhibits a descending trend with the NH₄Br addition and the removal rate reaches 17.31% with the addition amount of 0.3%. Adding NH₄Br to coal also plays a synergistic role in denitration.

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Memo

Memo:

Biographies: Zhao Shilin(1992—), male, graduate; Duan Yufeng(corresponding author), male, doctor, professor, yfduan@seu.edu.cn.
Foundation items: The National Natural Science Foundation of China(No.51376046, 51076030), the National Key Technology R&D Program of China during the 12th Five-Year Plan Period(No.2012BAA02B01), the United Creative Foundation of Jiangsu Province(No.BY2013073-10), the Fundamental Research Funds for the Central Universities, the Scientific Innovation Research of College Graduates in Jiangsu Province(CXZZ13_0093, KYLX_0115, KYLX_0184).
Citation: Zhao Shilin, Duan Yufeng, Zhou Qiang, et al. Experimental studies on gas-phase mercury oxidation removal and denitration of coal combustion with NH₄Br addition[J].Journal of Southeast University(English Edition), 2015, 31(2):226-231.[doi:10.3969/j.issn.1003-7985.2015.02.012]

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