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Wang Y, Zhang Y, Xu J, Zhong J, Wei F, Zhang J, Zheng Y, Qian G. Footprints in compositions, PCDD/Fs and heavy metals in medical waste fly ash: Large-scale evidence from 17 medical waste thermochemical disposal facilities across China. JOURNAL OF HAZARDOUS MATERIALS 2023; 445:130471. [PMID: 36455320 DOI: 10.1016/j.jhazmat.2022.130471] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Revised: 11/10/2022] [Accepted: 11/23/2022] [Indexed: 06/17/2023]
Abstract
Chemical compositions, polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) profiles and heavy metals (HMs) leachability of medical waste fly ash (MWFA) from 17 thermochemical treatment facilities in eight Chinese provinces were first investigated. Large-scale and extended monitoring revealed high chloride and Zn contents and similar PCDD/Fs congener profiles in MWFA. Particularly, the PCDD/Fs and HMs concentrations implied greater toxicity than that observed for municipal solid waste incinerator fly ash (MSWIFA). The maximum international toxic equivalent value of PCDD/Fs in MWFA was 40 times that of MSWIFA, and the leaching concentrations of Zn and Hg were 15 and 4 times those of MSWIFA, respectively. Notably, MWFA characteristics suggest the possibility of recycling and sustainable disposal solutions owing to the high Cl and Zn content with good recovery instead of landfill disposal. Similarities in chemical composition, PCDD/Fs homolog distribution, and water-solubility of chloride salts allows co-processing of MWFA and MSWIFA via water-washing detoxification and thermal treatment, such as that used in cement kilns. This study supplements existing literature on the characteristics and risk management of MWFA.
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Affiliation(s)
- Yao Wang
- SHU Center of Green Urban Mining & Industry Ecology, School of Environmental and Chemical Engineering, Shanghai University, 381 Nanchen Road, Shanghai 200444, China; Shanghai Institute of Geological Survey, 930 Lingshi Rd, Shanghai 200072, China.
| | - Yu Zhang
- SHU Center of Green Urban Mining & Industry Ecology, School of Environmental and Chemical Engineering, Shanghai University, 381 Nanchen Road, Shanghai 200444, China.
| | - Juan Xu
- Solid Waste and Chemicals Management Center, Ministry of Ecology and Environment, 1 Yuhui South Road, Beijing 100029, China.
| | - Jiangping Zhong
- Shanghai Solid Waste Disposal Center, 2491 Jiazhu Road, Shanghai 201815, China.
| | - Feng Wei
- Shanghai Solid Waste Disposal Center, 2491 Jiazhu Road, Shanghai 201815, China.
| | - Jia Zhang
- SHU Center of Green Urban Mining & Industry Ecology, School of Environmental and Chemical Engineering, Shanghai University, 381 Nanchen Road, Shanghai 200444, China.
| | - Yang Zheng
- Solid Waste and Chemicals Management Center, Ministry of Ecology and Environment, 1 Yuhui South Road, Beijing 100029, China.
| | - Guangren Qian
- SHU Center of Green Urban Mining & Industry Ecology, School of Environmental and Chemical Engineering, Shanghai University, 381 Nanchen Road, Shanghai 200444, China.
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2
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Wang B, Jiang Z, Wang T, Tang Q, Yu M, Feng T, Tian M, Chang R, Yue Y, Pan Z, Zhao J, Li X. Controllable Synthesis of Vacancy-Defect Cu Site and Its Catalysis for the Manufacture of Vinyl Chloride Monomer. ACS Catal 2021. [DOI: 10.1021/acscatal.1c01921] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Bolin Wang
- Institute of Industrial Catalysis, Zhejiang University of Technology, Hangzhou 310014, China
- Department of Environmental Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Zhao Jiang
- Institute of Industrial Catalysis, Zhejiang University of Technology, Hangzhou 310014, China
| | - Ting Wang
- Institute of Industrial Catalysis, Zhejiang University of Technology, Hangzhou 310014, China
| | - Qi Tang
- Institute of Industrial Catalysis, Zhejiang University of Technology, Hangzhou 310014, China
| | - Mingde Yu
- Institute of Industrial Catalysis, Zhejiang University of Technology, Hangzhou 310014, China
| | - Tao Feng
- Institute of Industrial Catalysis, Zhejiang University of Technology, Hangzhou 310014, China
| | - Min Tian
- Institute of Industrial Catalysis, Zhejiang University of Technology, Hangzhou 310014, China
| | - Renqin Chang
- Research Center of Analysis Measurement, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yuxue Yue
- Institute of Industrial Catalysis, Zhejiang University of Technology, Hangzhou 310014, China
| | - Zhiyan Pan
- Department of Environmental Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Jia Zhao
- Institute of Industrial Catalysis, Zhejiang University of Technology, Hangzhou 310014, China
| | - Xiaonian Li
- Institute of Industrial Catalysis, Zhejiang University of Technology, Hangzhou 310014, China
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Lane DJ, Jokiniemi J, Heimonen M, Peräniemi S, Kinnunen NM, Koponen H, Lähde A, Karhunen T, Nivajärvi T, Shurpali N, Sippula O. Thermal treatment of municipal solid waste incineration fly ash: Impact of gas atmosphere on the volatility of major, minor, and trace elements. WASTE MANAGEMENT (NEW YORK, N.Y.) 2020; 114:1-16. [PMID: 32622291 DOI: 10.1016/j.wasman.2020.06.035] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 05/18/2020] [Accepted: 06/23/2020] [Indexed: 06/11/2023]
Abstract
Development of thermal processes for selective recovery of Zn and other valuable elements from municipal solid waste incineration (MSWI) fly ash requires comprehensive knowledge of the impact of gas atmosphere on the volatile behaviour of the element constituents of the ash at different reaction temperatures. This study assesses the partitioning of 18 elements (Al, As, Bi, C, Ca, Cd, Cl, Cu, K, Mg, Na, P, Pb, S, Sb, Sn, Ti, and Zn) between condensed and gaseous phases during thermal treatment of MSWI fly ash in both oxidising gas and reducing gas atmospheres, at different temperatures spanning the range 200-1050 °C. The operating atmosphere had major impacts on the partitioning of the following elements: As, Bi, C, Cd, Cu, Na, Pb, S, Sb, Sn, and Zn. The partitioning of these elements cannot be accurately predicted over the full range of investigated operating conditions with global thermodynamic equilibrium calculations alone, i.e. without also considering chemical kinetics and mass transfer. In oxidising conditions, the following elements were predominately retained in condensed phases, even at high temperatures: As, Bi, Sb, Sn, and Zn. All these elements, except As, were largely released to the gas phase (>70%) at high temperatures in reducing conditions. The impact of gas atmosphere on the volatility of Cd and Pb was greatest at low reaction temperatures (below ~750 °C). Results for volatile matrix elements, specifically C, Cl, K, Na, and S, are interpreted in terms of the mechanisms governing the release of these elements to the gas phase.
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Affiliation(s)
- Daniel J Lane
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland.
| | - Jorma Jokiniemi
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Mikko Heimonen
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Sirpa Peräniemi
- School of Pharmacy, University of Eastern Finland, FI-70211 Kuopio, Finland
| | - Niko M Kinnunen
- Department of Chemistry, University of Eastern Finland, FI-80130 Joensuu, Finland
| | - Hanna Koponen
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Anna Lähde
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Tommi Karhunen
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Taina Nivajärvi
- Department of Chemistry, University of Eastern Finland, FI-80130 Joensuu, Finland
| | - Narasinha Shurpali
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Olli Sippula
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland; Department of Chemistry, University of Eastern Finland, FI-80130 Joensuu, Finland
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Xie K, Hu H, Xu S, Chen T, Huang Y, Yang Y, Yang F, Yao H. Fate of heavy metals during molten salts thermal treatment of municipal solid waste incineration fly ashes. WASTE MANAGEMENT (NEW YORK, N.Y.) 2020; 103:334-341. [PMID: 31923840 DOI: 10.1016/j.wasman.2019.12.047] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 12/09/2019] [Accepted: 12/29/2019] [Indexed: 06/10/2023]
Abstract
Thermal treatment could effectively realize the detoxification of heavy metals in municipal solid waste incineration (MSWI) fly ash through the approach of removal or stabilization process. To lower the operating temperature and suppress the evaporation of heavy metals, a molten salts (NaCl-CaCl2) thermal treatment method was proposed for the detoxification of heavy metals from MSWI fly ash at a relatively mild condition (600/800 °C). The fate of heavy metals during the heating process and their stabilization properties in the remained ash slag after molten salts thermal treatment were investigated. The results showed that, compared with the traditional thermal treatment, heavy metals were more easily chlorinated by the means of molten salts thermal treatment. The well distributed chloride in molten salts facilitated the direct chlorination of PbO/CdO. Furthermore, Al2O3 in ash enhanced the indirect chlorination of CuO/PbO/CdO, except for ZnO. In contrast, SiO2 showed better performance in promoting the indirect chlorination of heavy metal oxides. Meanwhile, some Zn2+ was precipitated from molten salts as Si/Al-Zn composite oxides through the interactions with ash containing Si/Al oxides. On the other hand, the dissolved heavy metals in molten salts showed a good thermal stability during the thermal treatment. The volatilization fractions of all detected heavy metals were less than 5%. After the molten salts thermal treatment, heavy metals in the ash slag were well stabilized and the amount of heavy metals leached was significantly lower than that from the raw fly ash.
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Affiliation(s)
- Kang Xie
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Hongyun Hu
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
| | - Sihua Xu
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Tongzhou Chen
- Wuhan Research Institute of Materials Protection, Wuhan 430074, China
| | - Yongda Huang
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Yuhan Yang
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Fu Yang
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Hong Yao
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
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Gao J, Dong C, Zhao Y, Hu X, Qin W, Wang X, Zhang J, Xue J, Zhang X. Vitrification of municipal solid waste incineration fly ash with B 2O 3 as a fluxing agent. WASTE MANAGEMENT (NEW YORK, N.Y.) 2020; 102:932-938. [PMID: 31855693 DOI: 10.1016/j.wasman.2019.12.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 10/31/2019] [Accepted: 12/08/2019] [Indexed: 06/10/2023]
Abstract
In this paper, B2O3 was used as a fluxing agent to reduce the melting temperature of municipal solid waste incineration (MSWI) fly ash and promote the glassy phase formation. Ash fusion temperature (AFT) test, atomic absorption spectroscopy (AAS), X-ray diffraction(XRD), scanning electron microscope (SEM) and thermodynamic calculation were carried out. The results showed that the flow temperature decreased from 1211 °C to 986 °C with an increase in the B2O3 content from 0 to 15 wt%. The melting slag lead to a decrease in the surface area and an increase in the mass transfer resistance of heavy metals. Thus, the agglomeration of the fly ash particles became easier with the reduced viscosity of the liquid slag. The volatilization of Pb, Cd and Zn in fly ash was inhibited. The leaching behavior of heavy metals was evaluated, the results indicated that Zn and Cu were stable whereas the Pb and Cd were soluble in glassy slag.
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Affiliation(s)
- Jing Gao
- National Engineering Laboratory for Biomass Power Generation Equipment, School of Renewable Energy, North China Electric Power University, Beijing 102206, China
| | - Changqing Dong
- National Engineering Laboratory for Biomass Power Generation Equipment, School of Renewable Energy, North China Electric Power University, Beijing 102206, China; State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing 102206, China
| | - Ying Zhao
- National Engineering Laboratory for Biomass Power Generation Equipment, School of Renewable Energy, North China Electric Power University, Beijing 102206, China
| | - Xiaoying Hu
- National Engineering Laboratory for Biomass Power Generation Equipment, School of Renewable Energy, North China Electric Power University, Beijing 102206, China
| | - Wu Qin
- National Engineering Laboratory for Biomass Power Generation Equipment, School of Renewable Energy, North China Electric Power University, Beijing 102206, China
| | - Xiaoqiang Wang
- National Engineering Laboratory for Biomass Power Generation Equipment, School of Renewable Energy, North China Electric Power University, Beijing 102206, China
| | - Junjiao Zhang
- School of Energy, Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China
| | - Junjie Xue
- National Engineering Laboratory for Biomass Power Generation Equipment, School of Renewable Energy, North China Electric Power University, Beijing 102206, China
| | - Xuming Zhang
- National Engineering Laboratory for Biomass Power Generation Equipment, School of Renewable Energy, North China Electric Power University, Beijing 102206, China
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Lane DJ, Sippula O, Koponen H, Heimonen M, Peräniemi S, Lähde A, Kinnunen NM, Nivajärvi T, Shurpali N, Jokiniemi J. Volatilisation of major, minor, and trace elements during thermal processing of fly ashes from waste- and wood-fired power plants in oxidising and reducing gas atmospheres. WASTE MANAGEMENT (NEW YORK, N.Y.) 2020; 102:698-709. [PMID: 31794929 DOI: 10.1016/j.wasman.2019.11.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 10/15/2019] [Accepted: 11/17/2019] [Indexed: 06/10/2023]
Abstract
This study assesses the volatility of 15 elements (As, Bi, C, Cd, Cl, Cu, K, Mn, Na, P, Pb, S, Sb, Sn, and Zn) during thermal processing of fly ashes obtained from four waste-to-energy plants and one wood-combustion plant. Differences in volatility in oxidising and reducing atmospheres (air and 10% H2/90% N2) were assessed at two temperatures, 700 and 1000 °C. P and Mn were predominately retained in all ashes regardless of the operating atmosphere and temperature. Other elements showed significant variation in volatility depending on the type of fly ash, atmosphere, and temperature. Heat-treatment of the wood-combustion fly ash in the air atmosphere resulted in low release of K, Na, and all investigated heavy metals and metalloids. Several valuable elements, including Zn, Sb, Sn, and Bi, were significantly more volatile in the reducing atmosphere than in the oxidising atmosphere, particularly at 1000 °C. Other elements were either less volatile, equally volatile, or only marginally more volatile when the ashes were heated at 1000 °C in the reducing atmosphere. These elements include C, Cl, Cu, and, in the case of fly ashes derived from municipal solid waste, Cd and Pb. A two-step process, in which municipal solid waste incineration fly ash is first heated in an oxidising atmosphere and then in a reducing atmosphere, is proposed for production of a chloride-free zinc concentrate. Evaluation of the two-step process at 880 °C shows good potential for selective volatilisation of Zn with other valuable elements, including Sn, Sb, and Bi.
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Affiliation(s)
- Daniel J Lane
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland.
| | - Olli Sippula
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland; Department of Chemistry, University of Eastern Finland, FI-80130 Joensuu, Finland
| | - Hanna Koponen
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Mikko Heimonen
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Sirpa Peräniemi
- School of Pharmacy, University of Eastern Finland, FI-70211 Kuopio, Finland
| | - Anna Lähde
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Niko M Kinnunen
- Department of Chemistry, University of Eastern Finland, FI-80130 Joensuu, Finland
| | - Taina Nivajärvi
- Department of Chemistry, University of Eastern Finland, FI-80130 Joensuu, Finland
| | - Narasinha Shurpali
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Jorma Jokiniemi
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
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Tian S, Zhu Y, Meng B, Guan J, Nie Z, Die Q, Xu W, Yu M, Huang Q. Chemical speciation of lead in secondary fly ash using X-ray absorption spectroscopy. CHEMOSPHERE 2018; 197:362-366. [PMID: 29407806 DOI: 10.1016/j.chemosphere.2018.01.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2017] [Revised: 01/01/2018] [Accepted: 01/07/2018] [Indexed: 06/07/2023]
Abstract
In this study, fly ash samples were collected from bag houses in a Chinese municipal solid waste incinerator (MSWI) and secondary fly ash (SFA) samples were collected from a high-temperature tubular electric furnace by thermal treatment of MSWI fly ash at 1050, 1100, 1150, 1200, and 1250 °C.We determined the speciation and atomic coordinates of lead in SFA using X-ray absorption spectroscopy (XAS) techniques. The results obtained by X-ray absorption near edge structure (XANES) spectra revealed that the mass fraction of PbO in MSWI fly ash was 57.9% (wt %) while PbCl2 and PbS were the dominant species in SFA. Extended X-ray absorption fine structure (EXAFS) data analysis indicated the atomic coordinates of Pb were proportional to the weights of PbCl2 and PbS, in good agreement with the XANES spectra. These findings highlight lead evaporation processes in the MSWI fly ash during heat treatment and provide a method for consistent speciation analysis of environmental samples using XAS.
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Affiliation(s)
- Shulei Tian
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yingcai Zhu
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Bangbang Meng
- College of Chemical and Environmental Engineering, Harbin University of Science and Technology, Harbin 150040, China
| | - Jian Guan
- Tangshan Iron and Steel Group Company Limited, Energy and Environmental Protection Department, Tangshan 063000, China
| | - Zhiqiang Nie
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Qingqi Die
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Wei Xu
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Meijuan Yu
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
| | - Qifei Huang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
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8
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Chen W, Kirkelund GM, Jensen PE, Ottosen LM. Comparison of different MSWI fly ash treatment processes on the thermal behavior of As, Cr, Pb and Zn in the ash. WASTE MANAGEMENT (NEW YORK, N.Y.) 2017; 68:240-251. [PMID: 28757224 DOI: 10.1016/j.wasman.2017.07.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 05/26/2017] [Accepted: 07/11/2017] [Indexed: 06/07/2023]
Abstract
To reduce heavy metal leaching and stabilize municipal solid waste incineration (MSWI) fly ash, different methods and combination of methods were tested: water washing, electrodialytic separation and thermal treatment at 1000°C. A comparison of heavy metal concentration and leaching levels of As, Cr, Pb and Zn for the different untreated and treated ashes was made. The results showed that minimizing leaching to meet the limiting values of the all the studied heavy metals can be obtained at the same time by combining water washing, electrodialytic separation and thermal treatment. The ash subjected to this combination had lower Cr than the ash solely subjected to thermal treatment or subjected to water washing prior to thermal treatment. The electrodialytic separation (EDS) of the washed ash lowered pH from alkaline to acidic, which resulted in elevated leaching of Cd and Zn, while the Cr leaching was reduced. Up to 58.6% of Zn and 5.5% of Pb were extracted by EDS compared to less than 0.6% extraction by water washing. During thermal treatment of the EDS treated ash, the ash was re-alkalized. Due to solidification and possibly evaporation, most heavy elements left in the thermally treated ash were stabilized and immobilized. However, leaching of As and/or Cr was still problematic and did not meet the limit value for the thermally treated ash being recycled in construction work. The removal of Ca and decomposition of Ca oxides and minerals during EDS was linked to the leaching patterns of As and Cr after thermal treatment.
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Affiliation(s)
- Wan Chen
- Department of Civil Engineering, Technical University of Denmark, Denmark.
| | - Gunvor M Kirkelund
- Department of Civil Engineering, Technical University of Denmark, Denmark
| | - Pernille E Jensen
- Department of Civil Engineering, Technical University of Denmark, Denmark
| | - Lisbeth M Ottosen
- Department of Civil Engineering, Technical University of Denmark, Denmark
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Yu S, Zhang B, Wei J, Zhang T, Yu Q, Zhang W. Effects of chlorine on the volatilization of heavy metals during the co-combustion of sewage sludge. WASTE MANAGEMENT (NEW YORK, N.Y.) 2017; 62:204-210. [PMID: 28283225 DOI: 10.1016/j.wasman.2017.02.029] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 01/22/2017] [Accepted: 02/25/2017] [Indexed: 06/06/2023]
Abstract
To clarify the volatilization of heavy metals (Cu, Ni, Pb, and Zn) in sewage sludge during co-combustion in cement kiln, effects of addition and types of four chlorides and temperature on the volatilization of heavy metals in raw meal with 25wt.% sewage sludge were investigated. The results showed that the volatilization of Cu, Ni, and Pb increased significantly with increase of chlorides addition, while no obvious change in the volatilization of Zn was observed. The effectiveness of chlorides on the volatilization of heavy metals depended on their release capacity of chlorine radicals and the chlorine combined capacity of heavy metals. Higher calcination temperature resulted in dramatically increase in the volatilization of heavy metals due to easier formation of volatile heavy metal chlorides. The results will provide a guideline for co-combusting heavy metals contained solid wastes in cement kiln on the basis of security.
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Affiliation(s)
- Shengrong Yu
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, Guangdong, China
| | - Bin Zhang
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, Guangdong, China
| | - Jiangxiong Wei
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, Guangdong, China; Guangdong Low Carbon Technologies Engineering Center for Building Materials, Guangzhou 510640, Guangdong, China.
| | - Tongsheng Zhang
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, Guangdong, China
| | - Qijun Yu
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, Guangdong, China; Guangdong Low Carbon Technologies Engineering Center for Building Materials, Guangzhou 510640, Guangdong, China
| | - Wensheng Zhang
- China Building Materials Academic, Beijing 100024, China
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10
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Yu J, Sun L, Ma C, Qiao Y, Xiang J, Hu S, Yao H. Mechanism on heavy metals vaporization from municipal solid waste fly ash by MgCl₂⋅6H₂O. WASTE MANAGEMENT (NEW YORK, N.Y.) 2016; 49:124-130. [PMID: 26748437 DOI: 10.1016/j.wasman.2015.12.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 11/21/2015] [Accepted: 12/19/2015] [Indexed: 06/05/2023]
Abstract
This work aims to study the mechanism of heavy metals vaporization by MgCl2⋅6H2O. Firstly, the decomposition mechanism of MgCl2⋅6H2O was investigated by thermodynamic equilibrium calculations, XRD and TG. Upon heating, MgCl2⋅6H2O went through the processes of dehydration and hydrolysis simultaneously accompanied by the release of HCl between 150 and 500°C. At temperature higher than 500°C, Mg(OH)Cl gradually release part of HCl. MgCl2⋅6H2O followed the similar processes of decomposition at both oxidative and reductive atmospheres. In oxidative atmosphere, vaporization of Zn and Cu was significantly accelerated by MgCl2⋅6H2O. However, in inert atmosphere, vaporization of Cu was not promoted since copper chloride was only stable in oxidative atmosphere. Under slow heating condition, vaporization of heavy metals were close to that under fast heating condition. This may be partially attributed to that most heavy metals already reacted with HCl forming metal chlorides below 500°C, which can be vaporized at higher temperature. Moreover, the Mg(OH)Cl contributed to release HCl up to 800°C. At such high temperature, the metal chlorides continue to be formed and then vaporized. After treatment, the leaching concentration of heavy metals from treated fly ashes were much lower than that from raw fly ash and met the regulatory limit of leachate. Since a large amount of MgSiO3 were formed during thermal treatment, the fly ash treated with MgCl2⋅6H2O can be used as raw materials for glass-ceramics production.
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Affiliation(s)
- Jie Yu
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China
| | - Lushi Sun
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China.
| | - Chuan Ma
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China
| | - Yu Qiao
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China
| | - Jun Xiang
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China
| | - Song Hu
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China
| | - Hong Yao
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China
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Fujimori T, Itai T, Goto A, Asante KA, Otsuka M, Takahashi S, Tanabe S. Interplay of metals and bromine with dioxin-related compounds concentrated in e-waste open burning soil from Agbogbloshie in Accra, Ghana. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 209:155-63. [PMID: 26686056 DOI: 10.1016/j.envpol.2015.11.031] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2015] [Revised: 11/12/2015] [Accepted: 11/19/2015] [Indexed: 05/25/2023]
Abstract
Open burning of electronic waste (e-waste) releases various metals and organohalogen compounds in the environment. Here we investigated the interplay of metals (Cu, Pb, Zn, Fe, Co, and Sr) and bromine (Br) in the formation of dioxin-related compounds (DRCs), including polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs), as well as non-regulated DRCs such as polybrominated dibenzo-p-dioxins/furans (PBDD/Fs) and their monobrominated PCDD/Fs in soils sampled from open burning e-waste sites at Agbogbloshie in Accra, Ghana. The predominant DRCs were PBDFs, PCDFs, PCDDs, and DL-PCBs. Statistical analyzes, X-ray absorption spectroscopy, and the PCDF/PCDD ratio suggested possible formation paths of PCDD/Fs and DL-PCBs by catalytic behaviors of copper chlorides (CuCl, CuCl2, and Cu2(OH)3Cl) and thermal breakdown of polyvinyl chloride. Predominant formation of brominated furans may be derived from electron transfer from intermediates of PBDE to copper, Cu(II) → Cu(I). Lead chloride also contributed to generate DRCs and may become highly bioaccessible through the open burning of e-waste. The main zinc species (ZnCl2 and ZnS) suggested a possible relationship to generate DRCs and specific zinc source such as tire burning. Cu, Pb, Zn, and Br contained in various e-wastes, wires/cables, plastics, and tires strongly influenced generation of many DRCs.
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Affiliation(s)
- Takashi Fujimori
- Department of Global Ecology, Graduate School of Global Environmental Studies, Kyoto University, Katsura, Nisikyo-ku, Kyoto, 615-8540, Japan; Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Katsura, Nisikyo-ku, Kyoto, 615-8540, Japan
| | - Takaaki Itai
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama, Ehime 790-8577, Japan.
| | - Akitoshi Goto
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama, Ehime 790-8577, Japan
| | - Kwadwo A Asante
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama, Ehime 790-8577, Japan; CSIR Water Research Institute, PO Box AH 38, Achimota, Accra, Ghana
| | - Masanari Otsuka
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama, Ehime 790-8577, Japan; Ehime Prefectural Institute of Public Health and Environmental Science, 8-234 Sanban-cho, Matsuyama 790-0003, Japan
| | - Shin Takahashi
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama, Ehime 790-8577, Japan; Department of Environmental Conservation, Ehime University, Matsuyama 790-8577, Japan
| | - Shinsuke Tanabe
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama, Ehime 790-8577, Japan
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Enhanced photocatalytic degradation of sulfamethoxazole by visible-light-sensitive TiO2 with low Cu addition. Sep Purif Technol 2015. [DOI: 10.1016/j.seppur.2015.10.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Yu J, Qiao Y, Jin L, Ma C, Paterson N, Sun L. Removal of toxic and alkali/alkaline earth metals during co-thermal treatment of two types of MSWI fly ashes in China. WASTE MANAGEMENT (NEW YORK, N.Y.) 2015; 46:287-297. [PMID: 26303652 DOI: 10.1016/j.wasman.2015.08.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2015] [Revised: 08/04/2015] [Accepted: 08/05/2015] [Indexed: 06/04/2023]
Abstract
This study aims to vaporize heavy metals and alkali/alkaline earth metals from two different types of fly ashes by thermal treatment method. Fly ash from a fluidized bed incinerator (HK fly ash) was mixed with one from a grate incinerator (HS fly ash) in various proportions and thermally treated under different temperatures. The melting of HS fly ash was avoided when treated with HK fly ash. Alkali/alkaline earth metals in HS fly ash served as Cl-donors to promote the vaporization of heavy metals during thermal treatment. With temperature increasing from 800 to 900°C, significant amounts of Cl, Na and K were vaporized. Up to 1000°C in air, less than 3% of Cl and Na and less than 5% of K were retained in ash. Under all conditions, Cd can be vaporized effectively. The vaporization of Pb was mildly improved when treated with HS fly ash, while the effect became less pronounced above 900°C. Alkali/alkaline earth metals can promote Cu vaporization by forming copper chlorides. Comparatively, Zn vaporization was low and only slightly improved by HS fly ash. The low vaporization of Zn could be caused by the formation of Zn2SiO4, ZnFe2O4 and ZnAl2O4. Under all conditions, less than 20% of Cr was vaporized. In a reductive atmosphere, the vaporization of Cd and Pb were as high as that in oxidative atmosphere. However, the vaporization of Zn was accelerated and that of Cu was hindered because the formation of Zn2SiO4, ZnFe2O4 and ZnAl2O4 and copper chloride was depressed in reductive atmosphere.
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Affiliation(s)
- Jie Yu
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China
| | - Yu Qiao
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China.
| | - Limei Jin
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China
| | - Chuan Ma
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China
| | - Nigel Paterson
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, United Kingdom
| | - Lushi Sun
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China
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Yu J, Qiao Y, Sun L, Jin L, Wang W, Ma C. Detoxification of ashes from a fluidized bed waste incinerator. CHEMOSPHERE 2015; 134:346-354. [PMID: 25973859 DOI: 10.1016/j.chemosphere.2015.04.045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Revised: 04/08/2015] [Accepted: 04/19/2015] [Indexed: 06/04/2023]
Abstract
This paper was to test and control the toxicity of bottom and fly ashes from a circulated fluidized bed (CFB) incinerator. Bottom and fly ashes were firstly subject to TCLP test. Even though leachates of most particle size of bottom ash were below regulatory limit, the leachates of finer bottom ash may exceed the regulatory limit. Therefore, finer bottom ash should be separated and treated before landfilled directly or used as cement replacement. Due to high amounts of leached heavy metals, thermal treatment of fly ash was carried out to remove heavy metals. The influence of temperature, residence time, metal chloride and gas velocity were studied. In all conditions, Cd can be well removed. Pb can be almost completely removed with MgCl2 addition at 1000°C in 1h. The removal of Zn and Cu was accelerated significantly by MgCl2 and higher temperature separately. At optimum conditions, more than 90% of Cu and 95% of Zn could be removed, while a maximum 20% of Cr was removed due to the existence or formation of CaCr2O4, MgCr2O4 and K2Cr2O4 in raw or treated fly ashes.
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Affiliation(s)
- Jie Yu
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China
| | - Yu Qiao
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China.
| | - Lushi Sun
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China.
| | - Limei Jin
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China
| | - Wenxia Wang
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China
| | - Chuan Ma
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, 430074 Wuhan, Hubei, China
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Lassesson H, Fedje KK, Steenari BM. Leaching for recovery of copper from municipal solid waste incineration fly ash: influence of ash properties and metal speciation. WASTE MANAGEMENT & RESEARCH : THE JOURNAL OF THE INTERNATIONAL SOLID WASTES AND PUBLIC CLEANSING ASSOCIATION, ISWA 2014; 32:755-762. [PMID: 25106538 DOI: 10.1177/0734242x14542147] [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: 06/03/2023]
Abstract
Recovery of metals occurring in significant amounts in municipal solid waste incineration fly ash, such as copper, could offer several advantages: a decreased amount of potentially mobile metal compounds going to landfill, saving of natural resources and a monetary value. A combination of leaching and solvent extraction may constitute a feasible recovery path for metals from municipal solid waste incineration fly ash. However, it has been shown that the initial dissolution and leaching is a limiting step in such a recovery process. The work described in this article was focused on elucidating physical and chemical differences between two ash samples with the aim of explaining the differences in copper release from these samples in two leaching methods. The results showed that the chemical speciation is an important factor affecting the release of copper. The occurrence of copper as phosphate or silicate will hinder leaching, while sulphate and chloride will facilitate leaching.
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Affiliation(s)
- Henric Lassesson
- Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Karin Karlfeldt Fedje
- Recycling and Waste Management, Gothenburg, Sweden Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Britt-Marie Steenari
- Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
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Zhu YM, Zhang H, Fan SS, Wang SJ, Xia Y, Shao LM, He PJ. In-situ determination of metallic variation and multi-association in single particles by combining synchrotron microprobe, sequential chemical extraction and multivariate statistical analysis. JOURNAL OF HAZARDOUS MATERIALS 2014; 276:241-252. [PMID: 24887126 DOI: 10.1016/j.jhazmat.2014.05.039] [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: 12/11/2013] [Revised: 04/20/2014] [Accepted: 05/14/2014] [Indexed: 06/03/2023]
Abstract
Due to the heterogeneity of metal distribution, it is challenging to identify the speciation, source and fate of metals in solid samples at micro scales. To overcome these challenges single particles of air pollution control residues were detected in situ by synchrotron microprobe after each step of chemical extraction and analyzed by multivariate statistical analysis. Results showed that Pb, Cu and Zn co-existed as acid soluble fractions during chemical extraction, regardless of their individual distribution as chlorides or oxides in the raw particles. Besides the forms of Fe2O3, MnO2 and FeCr2O4, Fe, Mn, Cr and Ni were closely associated with each other, mainly as reducible fractions. In addition, the two groups of metals had interrelations with the Si-containing insoluble matrix. The binding could not be directly detected by micro-X-ray diffraction (μ-XRD) and XRD, suggesting their partial existence as amorphous forms or in the solid solution. The combined method on single particles can effectively determine metallic multi-associations and various extraction behaviors that could not be identified by XRD, μ-XRD or X-ray absorption spectroscopy. The results are useful for further source identification and migration tracing of heavy metals.
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Affiliation(s)
- Yu-Min Zhu
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, PR China; Institute of Waste Treatment and Reclamation, Tongji University, 1239 Siping Road, Shanghai 200092, PR China
| | - Hua Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, PR China.
| | - Shi-Suo Fan
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, PR China
| | - Si-Jia Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, PR China
| | - Yi Xia
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, PR China
| | - Li-Ming Shao
- Institute of Waste Treatment and Reclamation, Tongji University, 1239 Siping Road, Shanghai 200092, PR China; Research and Training Center on Rural Waste Management, Ministry of Housing and Urban-Rural Development of P.R. China, 1239 Siping Road, Shanghai 200092, PR China
| | - Pin-Jing He
- Institute of Waste Treatment and Reclamation, Tongji University, 1239 Siping Road, Shanghai 200092, PR China; Research and Training Center on Rural Waste Management, Ministry of Housing and Urban-Rural Development of P.R. China, 1239 Siping Road, Shanghai 200092, PR China.
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Fujimori T, Tanino Y, Takaoka M. Coexistence of Cu, Fe, Pb, and Zn oxides and chlorides as a determinant of chlorinated aromatics generation in municipal solid waste incinerator fly ash. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 48:85-92. [PMID: 24308371 DOI: 10.1021/es403585h] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We investigated chemical determinants of the generation of chlorinated aromatic compounds (aromatic-Cls), such as polychlorinated biphenyls (PCBs) and chlorobenzenes (CBzs), in fly ash from municipal solid waste incineration. The influences of the following on aromatic-Cls formation in model fly ash (MFA) were systematically examined quantitatively and statistically: (i) inorganic chlorides (KCl, NaCl, CaCl2), (ii) base materials (SiO2, Al2O3, CaCO3), (iii) metal oxides (CuO, Fe2O3, PbO, ZnO), (iv) metal chlorides (CuCl2, FeCl3, PbCl2, ZnCl2), and (v) "coexisting multi-models." On the basis of aromatic-Cls concentrations, the ∑CBzs/∑PCBs ratio, and the similarity between distribution patterns, MFAs were categorized into six groups. The results and analysis indicated that the formation of aromatic-Cls depended strongly on the "coexistence condition", namely multimodels composed of not only metal chlorides, but also of metal oxides. The precise replication of metal chloride to oxide ratios, such as the precise ratios of Cu-, Fe-, Pb-, and Zn-chlorides and oxides, may be an essential factor in changing the thermochemical formation patterns of aromatic-Cls. Although CuCl2 acted as a promoter of aromatic-Cls generation, statistical analyses implied that FeCl3 also largely influenced the generation of aromatic-Cls under mixture conditions. Various additional components of fly ash were also comprehensively analyzed.
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Affiliation(s)
- Takashi Fujimori
- Department of Global Ecology, Graduate School of Global Environmental Studies, and ‡Department of Environmental Engineering, Graduate School of Engineering, Kyoto University , Katsura, Nisikyo-ku, 615-8540, Kyoto, Japan
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Hu HY, Liu H, Shen WQ, Luo GQ, Li AJ, Lu ZL, Yao H. Comparison of CaO's effect on the fate of heavy metals during thermal treatment of two typical types of MSWI fly ashes in China. CHEMOSPHERE 2013; 93:590-596. [PMID: 23800595 DOI: 10.1016/j.chemosphere.2013.05.077] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2013] [Revised: 05/25/2013] [Accepted: 05/27/2013] [Indexed: 06/02/2023]
Abstract
Both grate and fluidized bed incinerators are widely used for MSW incineration in China. CaO addition for removing hazardous emissions from MSWI flue gas changes the characteristics of fly ash and affects the thermal behavior of heavy metals when the ash is reheated. In the present work, two types of MSWI fly ashes, sampled from both grate and fluidized bed incinerators respectively, were thermal treated at 1023-1323 K and the fate of heavy metals was observed. The results show that both of the fly ashes were rich in Ca and Ca-compounds were the main alkaline matter which strongly affected the leaching behavior of heavy metals. Ca was mostly in the forms of Ca(OH)2 and CaCO3 in the fly ash from grate incinerator in which nascent fly ash particles were covered by Ca-compounds. In contrast, the content of Ca was lower in the fly ash from fluidized bed incinerator and Ca was mostly in the form of CaSO4. Chemical reactions among Ca-compounds caused particle agglomeration in thermal treated fly ash from grate incinerator, restraining the heavy metals volatilization. In thermal treated fly ash from fluidized bed incinerator, Ca was converted into aluminosilicates especially at 1323 K which enhanced heavy metals immobilization, decreasing their volatile fractions as well as leaching concentrations. Particle agglomeration hardly affected the leaching behavior of heavy metals. However, it suppressed the leachable-CaCrO4 formation and lowered Cr leaching concentration.
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Affiliation(s)
- Hong-Yun Hu
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China
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