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Bai M, Du C, Zhao Y, Wang D, Zhang W, Qiu P. Process exploration for scale melting and solidifying of municipal solid waste incineration (MSWI) fly ash by horizontal cyclone melting furnace. WASTE MANAGEMENT (NEW YORK, N.Y.) 2024; 189:127-136. [PMID: 39186920 DOI: 10.1016/j.wasman.2024.08.021] [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: 04/24/2024] [Revised: 08/19/2024] [Accepted: 08/21/2024] [Indexed: 08/28/2024]
Abstract
This study used the horizontal tubular heating furnace to explore the melting potential of circulating fluidized bed (CFB) incinerator fly ash and mechanical grate furnace (MGF) incinerator fly ash. The horizontal cyclone melting furnace was then built to explore further the feasibility of scale melting of MSWI fly ash. The melting characteristic temperature, amorphous content, and heavy metal leaching concentration characterized the melting potential and solidification effect of MSWI fly ash. The experimental results show that the amorphous content of CFB fly ash after melting is up to 92.37%, and the volatilization rate of heavy metals Zn, Pb, and Ni does not exceed 30%. MGF fly ash exhibits the "sintering into shells" phenomenon during heating, and the leaching concentrations of heavy metals Pb in the sintered products still exceed the standard limits. In addition, the volatilization rates of heavy metals Cu, Zn, Cd, Pb, Cr, and Ni in Slag II are above 50%, and the volatilization rate of Cr reaches 85%. So, slag's amorphous content also affects heavy metals' volatilization rate. The MSWI fly ash melting characteristic temperature decreases with the decrease of alkalinity value. When the alkalinity value drops to 0.6, the melting characteristic temperature reaches its lowest value. Mixing 80% CFB fly ash or 50% MGF bottom ash into MGF fly ash can significantly enhance the melting potential to reduce hazardous waste. When using the horizontal cyclone melting furnace to process MSWI fly ash on a large scale, MSWI fly ash achieves an excellent melting effect with an amorphous content of over 93% at the positions of the furnace middle section, inner tail cone, slag discharge outlet, and flue gas outlet. The fly ash particles are in motion in the melting furnace, so the particle size distribution affects the melting effect of MSWI fly ash.
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Affiliation(s)
- Menglong Bai
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China
| | - Chuanming Du
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China
| | - Yijun Zhao
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China.
| | - Dawei Wang
- Wuhan Industrial Investment Holdings Group Co., Ltd., Wuhan 430200, P. R. China
| | - Wenda Zhang
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China
| | - Penghua Qiu
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China
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Song H, Huang Y, Pang J, Li Z, Zhu Z, Cheng H, Gao J, Zuo W, Zhou H. A study of the stabilization and solidification of heavy metals in co-vitrification of medical waste incineration ash and coal fly ash. WASTE MANAGEMENT (NEW YORK, N.Y.) 2024; 186:46-54. [PMID: 38852376 DOI: 10.1016/j.wasman.2024.06.003] [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: 12/14/2023] [Revised: 05/29/2024] [Accepted: 06/06/2024] [Indexed: 06/11/2024]
Abstract
Medical waste incineration ash (MWIA) has significant concentrations of heavy metals, dioxins, and chlorine that, if handled incorrectly, might cause permanent damage to the environment and humans. The low content of calcium (Ca), silicon (Si), and aluminum (Al) is a brand-new challenge for the melting technique of MWIA. This work added coal fly ash (CFA) to explore the effect of melting on the detoxication treatment of MWIA. It was found that the produced vitrification product has a high vitreous content (98.61%) and a low potential ecological risk, with an initial ash solidification rate of 67.38%. By quantitatively assessing the morphological distribution features of heavy metals in ashes before melting and molten products, the stabilization and solidification rules of heavy metals during the melting process were investigated. This work ascertained the feasibility of co-vitrification of MWIA and CFA. In addition, the high-temperature melting and vitrification accelerated the detoxification of MWIA and the solidification of heavy metals.
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Affiliation(s)
- Huikang Song
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China
| | - Yaji Huang
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China.
| | - Junfeng Pang
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China; China Everbright Greentech Limited., Nanjing 211164, China
| | - Zhiyuan Li
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China
| | - Zhicheng Zhu
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China
| | - Haoqiang Cheng
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China
| | - Jiawei Gao
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China
| | - Wu Zuo
- Jiangsu Environmental Engineering Technology Co., Ltd., Nanjing 210019, China
| | - Haiyun Zhou
- Jiangsu Environmental Engineering Technology Co., Ltd., Nanjing 210019, China
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Zhang M, Wu Y, Li Y, Zhou R, Yu H, Zhu X, Quan H, Li Y. Risk assessment for the long-term stability of fly ash-based cementitious material containing arsenic: Dynamic and semidynamic leaching. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 345:123361. [PMID: 38228264 DOI: 10.1016/j.envpol.2024.123361] [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: 08/28/2023] [Revised: 12/21/2023] [Accepted: 01/13/2024] [Indexed: 01/18/2024]
Abstract
Fly ash from municipal solid waste incineration (MSWIFA) contains leachable heavy metals (HMs), and the environmental risk of contained HMs is an important concern for its safe treatment and disposal. This paper presents a dynamic leaching test of fly ash-based cementitious materials containing arsenic (FCAC) in three particle sizes based on an innovative simulation of two acid rainfall conditions to investigate the long-term stability of FCAC under acid rain conditions. As well as semi-dynamic leaching test by simulating FCAC in three scenarios. Furthermore, the long-term stability risk of FCAC is evaluated using a sequential extraction procedure (SEP) and the potential risk assessment index. Results showed that the Al3+ in the FCAC dissolved and reacted with the OH- in solution to form Al(OH)3 colloids as the leaching time increased. Moreover, the oxidation of sulfide minerals in the slag produced oxidants, such as H2SO4 and Fe2(SO4)3, which further aggravated the oxidative dissolution of sulfides, thereby resulting in an overall decreasing pH value of the leachate. In addition, due to the varying particle sizes of the FCAC, surface area size, and adsorption site changes, the arsenic leaching process showed three stages of leaching characteristics, namely, initial, rapid, and slow release, with a maximum leaching concentration of 2.42 mg/L, the cumulative release of 133.78 mg/kg, and the cumulative release rate of 2.32%. The SEP test revealed that the reduced state of HMs in the raw slag was lowered substantially, and the acid extractable state and residual state of HMs were increased, which was conducive to lessening the risk of FCAC. Overall, the geological polymerization reaction of MSWIFA is a viable and promising solution to stabilize mining and industrial wastes and repurpose the wastes into construction materials.
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Affiliation(s)
- Mingliang Zhang
- College of Agriculture and Biological Science, Dali University, Dali, 671003, Yunnan, China; Key Laboratory of Ecological Microbial Remediation Technology of Yunnan Higher Education Institutes, Dali, 671003, Yunnan, China
| | - Ying Wu
- College of Agriculture and Biological Science, Dali University, Dali, 671003, Yunnan, China; Key Laboratory of Ecological Microbial Remediation Technology of Yunnan Higher Education Institutes, Dali, 671003, Yunnan, China
| | - Yinmei Li
- College of Agriculture and Biological Science, Dali University, Dali, 671003, Yunnan, China; Key Laboratory of Ecological Microbial Remediation Technology of Yunnan Higher Education Institutes, Dali, 671003, Yunnan, China
| | - Rongwu Zhou
- College of Agriculture and Biological Science, Dali University, Dali, 671003, Yunnan, China; Key Laboratory of Ecological Microbial Remediation Technology of Yunnan Higher Education Institutes, Dali, 671003, Yunnan, China
| | - Huijuan Yu
- College of Agriculture and Biological Science, Dali University, Dali, 671003, Yunnan, China; Key Laboratory of Ecological Microbial Remediation Technology of Yunnan Higher Education Institutes, Dali, 671003, Yunnan, China
| | - Xing Zhu
- Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China
| | - Hong Quan
- College of Agriculture and Biological Science, Dali University, Dali, 671003, Yunnan, China; Key Laboratory of Ecological Microbial Remediation Technology of Yunnan Higher Education Institutes, Dali, 671003, Yunnan, China
| | - Yuancheng Li
- College of Agriculture and Biological Science, Dali University, Dali, 671003, Yunnan, China; Key Laboratory of Ecological Microbial Remediation Technology of Yunnan Higher Education Institutes, Dali, 671003, Yunnan, China; Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China.
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Long Y, Song Y, Huang H, Yang Y, Shen D, Geng H, Ruan J, Gu F. Transformation behavior of heavy metal during Co-thermal treatment of hazardous waste incineration fly ash and slag/electroplating sludge. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 351:119730. [PMID: 38086123 DOI: 10.1016/j.jenvman.2023.119730] [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: 09/02/2023] [Revised: 11/11/2023] [Accepted: 11/25/2023] [Indexed: 01/14/2024]
Abstract
In this study, the behavior of heavy metal transformation during the co-thermal treatment of hazardous waste incineration fly ash (HWIFA) and Fe-containing hazardous waste (including hazardous waste incineration bottom slag (HWIBS) and electroplating sludge (ES)) was investigated. The findings demonstrated that such a treatment effectively reduced the static leaching toxicity of Cr and Pb. Moreover, when the treatment temperature exceeded 1000 °C, the co-thermal treated sample exhibited low concentrations of dynamically leached Cr, Pb, and Zn, indicating that these heavy metals were successful detoxified. Thermodynamic analyses and phase transformation results suggested that the formation of spinel and the gradual disappearance of chromium dioxide in the presence of Fe-containing hazardous wastes contributed to the solidification of chromium. Additionally, the efficient detoxification of Pb and Zn was attributed to their volatilization and entry into the liquid phase during the co-thermal treatment process. Therefore, this study sets an excellent example of the co-thermal treatment of hazardous wastes and the control of heavy metal pollution during the treatment process.
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Affiliation(s)
- Yuyang Long
- School of Environmental Science and Engineering, Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Zhejiang Engineering Research Center of Non-ferrous Metal Waste Recycling, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310012, China
| | - Yuhe Song
- School of Environmental Science and Engineering, Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Zhejiang Engineering Research Center of Non-ferrous Metal Waste Recycling, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310012, China
| | - HuanLin Huang
- Hangzhou Guiyuan Environmental Technology Co. Ltd, Hangzhou, Zhejiang, 310012, China
| | - Yuqiang Yang
- Hangzhou Guiyuan Environmental Technology Co. Ltd, Hangzhou, Zhejiang, 310012, China
| | - Dongsheng Shen
- School of Environmental Science and Engineering, Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Zhejiang Engineering Research Center of Non-ferrous Metal Waste Recycling, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310012, China
| | - Hairong Geng
- Zhejiang Huiheyuan Environmental Technology Co. Ltd., Jiaxing, Zhejiang, 314200, China
| | - Jinmu Ruan
- Shaoxing Shangyu Zhonglian Environmental Protection Co. Ltd., Shaoxing, Zhejiang, 312300, China
| | - Foquan Gu
- School of Environmental Science and Engineering, Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Zhejiang Engineering Research Center of Non-ferrous Metal Waste Recycling, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310012, China.
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Long Y, Song Y, Yang Y, Huang H, Fang H, Shen D, Geng H, Ruan J, Gu F. Co-vitrification of hazardous waste incineration fly ash and hazardous waste sludge based on CaO-SiO 2-Al 2O 3 system. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 338:117776. [PMID: 36965423 DOI: 10.1016/j.jenvman.2023.117776] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 03/18/2023] [Accepted: 03/19/2023] [Indexed: 06/18/2023]
Abstract
Based on the CaO-SiO2-Al2O3 system, the feasibility of co-vitrification of hazardous waste incineration fly ash (FA) and hazardous waste sludge (HWS) was verified. In the CaO-SiO2-Al2O3 ternary system diagram, the melting point of the system gradually decreases with an appropriate increase in SiO2 content when the CaO/Al2O3 ratio is determined to be approximately 1. The TG-DSC results revealed that the liquid phase generation temperature in the FA and HWS mixture system was significantly lower than those of FA and HWS individually owing to the different CaO, SiO2, and Al2O3 contents; this is consistent with the results of the theoretical melting characteristics analysis, which show that the melting characteristic temperatures can be reduced by controlling the CaO-SiO2-Al2O3 ratio in the system. The co-vitrification experimental results confirmed that a vitreous content above 92%, a loss ratio on acid dissolution less than 1.74%, and leaching toxicity of heavy metals lower than 0.15 mg/L could be obtained by adjusting the CaO, SiO2, and Al2O3 contents in the FA and HWS system to 20 wt%-32.5 wt%, 35 wt%-61 wt% and 14 wt%-32.5 wt%, respectively, and under a melting temperature of 1350 °C.
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Affiliation(s)
- Yuyang Long
- School of Environmental Science and Engineering, Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Zhejiang Engineering Research Center of Non-ferrous Metal Waste Recycling, Instrumental Analysis Center of Zhejiang Gongshang University, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310012, China
| | - Yuhe Song
- School of Environmental Science and Engineering, Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Zhejiang Engineering Research Center of Non-ferrous Metal Waste Recycling, Instrumental Analysis Center of Zhejiang Gongshang University, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310012, China
| | - Yuqiang Yang
- Hangzhou Guiyuan Environmental Technology Co. Ltd., Hangzhou, Zhejiang, 310012, China
| | - HuanLin Huang
- Hangzhou Guiyuan Environmental Technology Co. Ltd., Hangzhou, Zhejiang, 310012, China
| | - Haoyu Fang
- School of Environmental Science and Engineering, Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Zhejiang Engineering Research Center of Non-ferrous Metal Waste Recycling, Instrumental Analysis Center of Zhejiang Gongshang University, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310012, China
| | - Dongsheng Shen
- School of Environmental Science and Engineering, Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Zhejiang Engineering Research Center of Non-ferrous Metal Waste Recycling, Instrumental Analysis Center of Zhejiang Gongshang University, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310012, China
| | - Hairong Geng
- Zhejiang Huiheyuan Environmental Technology Co. Ltd., Jiaxing, Zhejiang, 314200, China
| | - Jinmu Ruan
- Shaoxing Shangyu Zhonglian Environmental Protection Co. Ltd., Shaoxing, Zhejiang, 312300, China
| | - Foquan Gu
- School of Environmental Science and Engineering, Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Zhejiang Engineering Research Center of Non-ferrous Metal Waste Recycling, Instrumental Analysis Center of Zhejiang Gongshang University, Zhejiang Gongshang University, Hangzhou, Zhejiang, 310012, China.
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