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He KQ, Zhang XR, Li YP, Duan XL, Li Y, Jiang YH, Yuan XD, Zhang KG, Yuan CG. Identification of mercury species in coal combustion by-products from power plants using thermal desorption-atomic fluorescence spectrometry on-line coupling system. CHEMOSPHERE 2023; 312:137206. [PMID: 36370763 DOI: 10.1016/j.chemosphere.2022.137206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 10/25/2022] [Accepted: 11/07/2022] [Indexed: 06/16/2023]
Abstract
Along with the environmental protection policies becoming strict in China, the air pollution control devices (especially selective catalytic reduction (SCR)) are widely equipped in coal-fired power plants. The installation and run of these devices will inevitably affect mercury (Hg) species distribution in coal fired by-products such like fly ash (FA) and gypsum. In this work, a new on-line coupling system based on atomic fluorescence spectrometry (AFS) with a home-made chromatographic workstation was successfully developed to identify Hg species through thermal programmed desorption (TPD). The influences of matrix, furnace temperature, and carrier gas flow on analytical performance were investigated and the parameters were optimized. The FA and gypsum samples from coal-fired power plants equipped with SCR were collected and the mercury species were analyzed by the developed coupling system. HgCl2 and HgO were the main species in FA, while Hg2Cl2 and HgO were the main species in gypsum. All of Hg species in the studied FA and gypsum samples were released below 400 °C. A sequential extraction procedure was applied to further verify the operational Hg species including mobile and non-mobile fractions in FA and gypsum samples. This study demonstrated that AFS coupled with TPD procedure was an effective method to analyze Hg species in coal combustion by-products from power plants.
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Affiliation(s)
- Kai-Qiang He
- Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control, Department of Environmental Science & Engineering, North China Electric Power University, Baoding, 071000, China; Department of Fire Engineering, China Fire and Rescue Institute, Beijing, 102200, China
| | - Xiao-Ru Zhang
- Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control, Department of Environmental Science & Engineering, North China Electric Power University, Baoding, 071000, China
| | - Yuan-Peng Li
- Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control, Department of Environmental Science & Engineering, North China Electric Power University, Baoding, 071000, China
| | - Xue-Lei Duan
- Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control, Department of Environmental Science & Engineering, North China Electric Power University, Baoding, 071000, China
| | - Yan Li
- Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control, Department of Environmental Science & Engineering, North China Electric Power University, Baoding, 071000, China
| | - Yang-Hong Jiang
- Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control, Department of Environmental Science & Engineering, North China Electric Power University, Baoding, 071000, China
| | - Xiao-Dong Yuan
- Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control, Department of Environmental Science & Engineering, North China Electric Power University, Baoding, 071000, China
| | - Ke-Gang Zhang
- Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control, Department of Environmental Science & Engineering, North China Electric Power University, Baoding, 071000, China
| | - Chun-Gang Yuan
- Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control, Department of Environmental Science & Engineering, North China Electric Power University, Baoding, 071000, China; MOE Key Laboratory of Resources and Environmental Systems Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China.
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Yang Y, Xu W, Wu Y, Xiong J, Zhu T, Zhou X, Tong L. Effect of HBr formation on mercury oxidation via CaBr2 addition to coal during combustion. RSC Adv 2016. [DOI: 10.1039/c6ra11468g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Adding CaBr2 to coal to enhance elemental mercury (Hg0) oxidation during combustion has been an effective mercury control technology, but the added CaBr2 may increase levels of noxious Br2 or HBr gases in flue gas.
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Affiliation(s)
- Yang Yang
- Research Center of Process Pollution Control
- National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology
- Institute of Process Engineering
- Chinese Academy of Sciences
- Beijing 100190
| | - Wenqing Xu
- Research Center of Process Pollution Control
- National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology
- Institute of Process Engineering
- Chinese Academy of Sciences
- Beijing 100190
| | - Yinghong Wu
- Research Center of Process Pollution Control
- National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology
- Institute of Process Engineering
- Chinese Academy of Sciences
- Beijing 100190
| | - Jin Xiong
- Research Center of Process Pollution Control
- National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology
- Institute of Process Engineering
- Chinese Academy of Sciences
- Beijing 100190
| | - Tingyu Zhu
- Research Center of Process Pollution Control
- National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology
- Institute of Process Engineering
- Chinese Academy of Sciences
- Beijing 100190
| | - Xuan Zhou
- Research Center of Process Pollution Control
- National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology
- Institute of Process Engineering
- Chinese Academy of Sciences
- Beijing 100190
| | - Li Tong
- Research Center of Process Pollution Control
- National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology
- Institute of Process Engineering
- Chinese Academy of Sciences
- Beijing 100190
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He J, Duan C, Lei M, Zhu X. The secondary release of mercury in coal fly ash-based flue-gas mercury removal technology. ENVIRONMENTAL TECHNOLOGY 2015; 37:28-38. [PMID: 26121324 DOI: 10.1080/09593330.2015.1059491] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The secondary release of mercury from coal fly ash is a negative by-product from coal-fired power plants, and requires effective control to reduce environmental pollution. Analysing particle size distribution and composition of the coal fly ash produced by different mercury removing technologies indicates that the particles are generally less than 0.5 mm in size and are composed mainly of SiO2, Al2O3, and Fe2O3. The relationships between mercury concentration in the coal fly ash, its particle size, and loss of ignition were studied using different mercury removing approaches. The research indicates that the coal fly ash's mercury levels are significantly higher after injecting activated carbon or brominating activated carbon when compared to regular cooperating-pollution control technology. This is particularly true for particle size ranges of >0.125, 0.075-0.125, and 0.05-0.075 mm. Leaching experiments revealed the secondary release of mercury in discarded coal fly ash. The concentration of mercury in the coal fly ash increases as the quantity of injecting activated carbon or brominating activated carbon increases. The leached concentrations of mercury increase as the particle size of the coal fly ash increases. Therefore, the secondary release of mercury can be controlled by adding suitable activated carbon or brominating activated carbon when disposing of coal fly ash. Adding CaBr2 before coal combustion in the boiler also helps control the secondary release of mercury, by increasing the Hg(2+) concentration in the leachate. This work provides a theoretical foundation for controlling and removing mercury in coal fly ash disposal.
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Affiliation(s)
- Jingfeng He
- a School of Chemical Engineering and Technology , China University of Mining and Technology , Xuzhou 221116 , People's Republic of China
- b Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education , China University of Mining and Technology , Xuzhou 221116 , People's Republic of China
| | - Chenlong Duan
- a School of Chemical Engineering and Technology , China University of Mining and Technology , Xuzhou 221116 , People's Republic of China
- b Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education , China University of Mining and Technology , Xuzhou 221116 , People's Republic of China
| | - Mingzhe Lei
- a School of Chemical Engineering and Technology , China University of Mining and Technology , Xuzhou 221116 , People's Republic of China
| | - Xuemei Zhu
- c Institute of solid waste management , Chinese Research Academy of Environmental Sciences , Beijing 100012 , People's Republic of China
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Córdoba P, Maroto-Valer M, Ayora C, Perry R, Rallo M, Font O, Izquierdo M, Querol X. Unusual speciation and retention of Hg at a coal-fired power plant. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:7890-7897. [PMID: 22702219 DOI: 10.1021/es301106x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
An unusual and different speciation of Hg in the outgoing gaseous stream of the flue gas desulfurization (OUT-FGD) system was revealed at two Spanish power plants (PP1 and PP2) equipped with a forced oxidation wet FGD system with water recirculation to the scrubber. At PP1 and PP2, a high proportion of Hg escapes from the electrostatic precipitator in gaseous form, Hg(2+) (75-86%) being the species that enters the FGD. At PP1 Hg(0) (71%) was the prevalent Hg OUT-FGD species, whereas at PP2 Hg(2+) was the prevalent Hg OUT-FGD species in 2007 (66%) and 2008 (87%). The unusual speciation of gaseous Hg OUT-FGD and the different Hg retentions between 2007 and 2008 at PP2 were attributable to the evaporation of HgCl(2) particles from the aqueous phase of gypsum slurry in the OUT-FGD gas and the Al additive used at PP2, respectively. The Al additive induced the retention of Hg as HgS in the 2007 FGD gypsum, thus reducing gaseous emissions of Hg in the OUT-FGD gas.
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Affiliation(s)
- Patricia Córdoba
- Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18-26, E-08034 Barcelona, Spain.
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