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Deng W, Fu P, Li J, Wang X, Zhang Y. Effect of long-term dry-wet circulations on the Solidification/stabilization of Municipal solid waste incineration fly ash using a novel cementitious material. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:24302-24314. [PMID: 38441736 DOI: 10.1007/s11356-024-32742-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 02/28/2024] [Indexed: 04/07/2024]
Abstract
Solidification/stabilization (S/S) is a typical technique to immobilize toxic heavy metals in Municipal solid waste incineration fly ash (MSWI FA). This study utilized blast furnace slag, steel slag, desulfurization gypsum, and phosphoric acid sludge to develop a novel metallurgical slag based cementing material (MSCM). Its S/S effects of MSWI FA and long-term S/S effectiveness under dry-wet circulations (DWC) were evaluated and compared with ordinary Portland cement (OPC). The MSCM-FA block with 25 wt.% MSCM content achieved 28-day compressive strength of 9.38 MPa, indicating its high hydration reactivity. The leaching concentrations of Pb, Zn and Cd were just 51.4, 1895.8 and 36.1 μg/L, respectively, well below the limit standard of Municipal solid wastes in China (GB 16889-2008). After 30 times' DWC, leaching concentrations of Pb, Zn and Cd for MSCM-FA blocks increased up to 130.7, 9107.4 and 156.8 μg/L, respectively, but considerably lower than those for OPC-FA blocks (689, 11,870.6 and 185.2 μg/L, respectively). The XRD and chemical speciation analysis revealed the desorption of Pb, Zn and Cd attached to surface of C-S-H crystalline structure during the DWC. The XPS and SEM-EDS analysis confirmed the formation of Pb-O-Si and Zn-O-Si bonds via isomorphous replacement of C-A-S-H in binder-FA blocks. Ettringite crystalline structure in OPC-FA block was severely destructed during the DWC, resulting in the reduced contents of PbSO4 and CaZn2Si2O7·H2O and the higher leachability of Pb2+ and Zn2+.
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Affiliation(s)
- Wei Deng
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Pingfeng Fu
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
| | - Jia Li
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Xiaoli Wang
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yuliang Zhang
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing, 100083, China
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Lan J, Dong Y, Kai MF, Hou H, Dai JG. Investigation of waste alkali-activated cementing material using municipal solid waste incineration fly ash and dravite as precursors: Mechanisms, performance, and on-site application. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133416. [PMID: 38183939 DOI: 10.1016/j.jhazmat.2023.133416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 12/23/2023] [Accepted: 12/29/2023] [Indexed: 01/08/2024]
Abstract
The proper treatment of municipal solid waste incineration fly ash (MSWIFA) is a crucial concern due to its hazardous nature and potential environmental harm. To address this issue, this study innovatively utilized dravite and black liquor to solidify MSWIFA. The semi-dry pressing method was employed, resulting in the production of waste alkali-activated cementing material (WACM). This material demonstrated impressive compressive and flexural strength, reaching 45.89 MPa and 6.55 MPa respectively, and effectively solidified heavy metal ions (Pb, Cr, Cu, Cd, and Zn). The leaching concentrations of these ions decreased from 27.15, 10.36, 8.94, 7.00, and 104.4 mg/L to 0.13, 1.05, 0.29, 0.06, and 12.28 mg/L, respectively. The strength of WACM increased by 3 times compared to conventionally produced materials. Furthermore, WACM exhibited excellent long-term performance, with acceptable heavy metal leaching and minimal mechanical degradation. Experimental and theoretical analyses revealed the heavy metal solidification mechanisms, including chemical binding, ion substitution and physical encapsulation. Finally, the on-site application of WACM confirmed its feasibility in meeting both environmental and strength requirements.
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Affiliation(s)
- Jirong Lan
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong Special Administrative Region
| | - Yiqie Dong
- School of Resource and Environmental Sciences, Wuhan University, Wuhan, China
| | - Ming-Feng Kai
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong Special Administrative Region.
| | - Haobo Hou
- School of Resource and Environmental Sciences, Wuhan University, Wuhan, China
| | - Jian-Guo Dai
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong Special Administrative Region; Department of Architecture and Civil Engineering, City University of Hong Kong, Kowloon, Hong Kong Special Administrative Region.
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3
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Sun M, Ma L, Dai Q, Yang J, Xie L, Hu Y, Duan L, Yan X, Zhou G, Zeng L, Shao L, Hu B, Yan Q. Preparation of functional geopolymers from municipal solid waste incineration fly ash: An approach combining experimental and computational simulation studies. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 355:120226. [PMID: 38430876 DOI: 10.1016/j.jenvman.2024.120226] [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: 12/08/2023] [Revised: 01/18/2024] [Accepted: 01/24/2024] [Indexed: 03/05/2024]
Abstract
This study aims to evaluate the feasibility and safety of using municipal solid waste incineration fly ash (MSW-IFA) in the development of geopolymer-based solidification/stabilization (S/S) treatments. Geopolymers have garnered attention as a sustainable alternative to traditional cement, owing to their high strength, stability, and minimal CO2 emissions. In this study, a combination of experimental and simulation calculations was used to investigate the setting time, mechanical properties, environmental risks, hydration mechanisms and processes of municipal solid waste incineration fly ash-based polymeric functional cementitious materials (GFCM). The results demonstrate that the mechanical properties of GFCM are related to the changes in the mineral phases and the degree of compactness. Quantum chemical calculations indicate that the hydration products may be [Si(OH)4], [Al(OH)3(OH2)] and [Al(OH)4]-. It is possible that the heavy metals are embedded in the hydrated silica-aluminate by electrostatic interaction or chemisorption. Heavy metals may be embedded in hydrated silica-aluminate by electrostatic action or chemisorption. This study provides a feasible method for resource utilization and heavy metal stabilization mechanism of MSW-IFA.
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Affiliation(s)
- Mingyi Sun
- College of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Liping Ma
- College of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China.
| | - Quxiu Dai
- College of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China.
| | - Jie Yang
- College of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China.
| | - Longgui Xie
- College of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Yao Hu
- College of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Li Duan
- College of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Xiang Yan
- College of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Guanyun Zhou
- College of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Linglong Zeng
- College of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Lan Shao
- College of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Bo Hu
- College of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650500, China
| | - Qichi Yan
- College of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan, 650500, 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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Khalid Z, Liu X, Duan Y, Lin S, Jiang X. Immobilization mechanisms of heavy metals by utilizing natural cow bone waste for municipal solid waste incineration fly ash treatment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:125585-125595. [PMID: 38006480 DOI: 10.1007/s11356-023-31180-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 11/18/2023] [Indexed: 11/27/2023]
Abstract
Municipal solid waste incinerator (MSWI) fly ash poses intricate compositional challenges and potential environmental hazards. Effective management of such hazardous waste is imperative to mitigate the release of toxic compounds into the environment. Solidification/stabilization (S/S) processes have emerged as a viable strategy to transform MSWI fly ash from incineration waste into a safer and more environmentally benign material. This study aims to comprehensively investigate the potential of utilizing cow bone waste to stabilize heavy metals, focusing on Pb, within municipal solid waste incineration fly ash. Experimental investigations encompassed cow bone-to-fly ash weight ratios ranging from 0.0 (control group) to 7:3, a settling time of 2 h, and a liquid-to-solid (L/S) ratio of 1.0 mL/g. Cow bone waste exhibited pronounced efficacy, particularly within the short settling time, yielding a remarkable Pb removal efficiency of up to 99% at a cow bone waste dose of merely 2% and an L/S ratio of 1.0 mL/g. Concurrently, other heavy metals such as Cd, Cu, and Zn were effectively stabilized with a cow bone waste dose of 1.5% during the same 2-h settling period. The results underscore the pivotal roles of ash/bone ratio and settling time in augmenting Pb stabilization in MSWI fly ash. The application of cow bone waste is anticipated to offer a cost-effective and environmentally sound approach, aligning with sustainable waste management principles.
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Affiliation(s)
- Zeinab Khalid
- State Key Laboratory of Clean Energy Utilization, Institute of Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, Zhejiang, China
- Zhejiang University Qingshanhu Energy Research Centre, Linan, Hangzhou, 311305, Zhejiang, China
| | - Xiaobo Liu
- State Key Laboratory of Clean Energy Utilization, Institute of Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, Zhejiang, China
- Zhejiang University Qingshanhu Energy Research Centre, Linan, Hangzhou, 311305, Zhejiang, China
| | - Yin Duan
- State Key Laboratory of Clean Energy Utilization, Institute of Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, Zhejiang, China
- Zhejiang University Qingshanhu Energy Research Centre, Linan, Hangzhou, 311305, Zhejiang, China
| | - Shunda Lin
- State Key Laboratory of Clean Energy Utilization, Institute of Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, Zhejiang, China
- Zhejiang University Qingshanhu Energy Research Centre, Linan, Hangzhou, 311305, Zhejiang, China
| | - Xuguang Jiang
- State Key Laboratory of Clean Energy Utilization, Institute of Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, Zhejiang, China.
- Zhejiang University Qingshanhu Energy Research Centre, Linan, Hangzhou, 311305, Zhejiang, China.
- Key Laboratory of Clean Energy and Carbon Neutrality of Zhejiang Province, Jiaxing Research Institute, Zhejiang University, 1300 Dongshengxilu Road, Jiaxing, 314031, China.
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Mondal S, Park S, Choi J, Vu TTH, Doan VHM, Vo TT, Lee B, Oh J. Hydroxyapatite: A journey from biomaterials to advanced functional materials. Adv Colloid Interface Sci 2023; 321:103013. [PMID: 37839281 DOI: 10.1016/j.cis.2023.103013] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 10/01/2023] [Accepted: 10/02/2023] [Indexed: 10/17/2023]
Abstract
Hydroxyapatite (HAp), a well-known biomaterial, has witnessed a remarkable evolution over the years, transforming from a simple biocompatible substance to an advanced functional material with a wide range of applications. This abstract provides an overview of the significant advancements in the field of HAp and its journey towards becoming a multifunctional material. Initially recognized for its exceptional biocompatibility and bioactivity, HAp gained prominence in the field of bone tissue engineering and dental applications. Its ability to integrate with surrounding tissues, promote cellular adhesion, and facilitate osseointegration made it an ideal candidate for various biomedical implants and coatings. As the understanding of HAp grew, researchers explored its potential beyond traditional biomaterial applications. With advances in material synthesis and engineering, HAp began to exhibit unique properties that extended its utility to other disciplines. Researchers successfully tailored the composition, morphology, and surface characteristics of HAp, leading to enhanced mechanical strength, controlled drug release capabilities, and improved biodegradability. These modifications enabled the utilization of HAp in drug delivery systems, biosensors, tissue engineering scaffolds, and regenerative medicine applications. Moreover, the exceptional biomineralization properties of HAp allowed for the incorporation of functional ions and molecules during synthesis, leading to the development of bioactive coatings and composites with specific therapeutic functionalities. These functionalized HAp materials have demonstrated promising results in antimicrobial coatings, controlled release systems for growth factors and therapeutic agents, and even as catalysts in chemical reactions. In recent years, HAp nanoparticles and nanostructured materials have emerged as a focal point of research due to their unique physicochemical properties and potential for targeted drug delivery, imaging, and theranostic applications. The ability to manipulate the size, shape, and surface chemistry of HAp at the nanoscale has paved the way for innovative approaches in personalized medicine and regenerative therapies. This abstract highlights the exceptional evolution of HAp, from a traditional biomaterial to an advanced functional material. The exploration of novel synthesis methods, surface modifications, and nanoengineering techniques has expanded the horizon of HAp applications, enabling its integration into diverse fields ranging from biomedicine to catalysis. Additionally, this manuscript discusses the emerging prospects of HAp-based materials in photocatalysis, sensing, and energy storage, showcasing its potential as an advanced functional material beyond the realm of biomedical applications. As research in this field progresses, the future holds tremendous potential for HAp-based materials to revolutionize medical treatments and contribute to the advancement of science and technology.
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Affiliation(s)
- Sudip Mondal
- Digital Healthcare Research Center, Institute of Information Technology and Convergence, Pukyong National University, Busan 48513, Republic of Korea
| | - Sumin Park
- Industry 4.0 Convergence Bionics Engineering, Department of Biomedical Engineering, Pukyong National University, Busan 48513, Republic of Korea
| | - Jaeyeop Choi
- Smart Gym-Based Translational Research Center for Active Senior's Healthcare, Pukyong National University, Busan 48513, Republic of Korea
| | - Thi Thu Ha Vu
- Industry 4.0 Convergence Bionics Engineering, Department of Biomedical Engineering, Pukyong National University, Busan 48513, Republic of Korea
| | - Vu Hoang Minh Doan
- Smart Gym-Based Translational Research Center for Active Senior's Healthcare, Pukyong National University, Busan 48513, Republic of Korea
| | - Truong Tien Vo
- Industry 4.0 Convergence Bionics Engineering, Department of Biomedical Engineering, Pukyong National University, Busan 48513, Republic of Korea
| | - Byeongil Lee
- Digital Healthcare Research Center, Institute of Information Technology and Convergence, Pukyong National University, Busan 48513, Republic of Korea; Industry 4.0 Convergence Bionics Engineering, Department of Biomedical Engineering, Pukyong National University, Busan 48513, Republic of Korea.
| | - Junghwan Oh
- Digital Healthcare Research Center, Institute of Information Technology and Convergence, Pukyong National University, Busan 48513, Republic of Korea; Industry 4.0 Convergence Bionics Engineering, Department of Biomedical Engineering, Pukyong National University, Busan 48513, Republic of Korea; Smart Gym-Based Translational Research Center for Active Senior's Healthcare, Pukyong National University, Busan 48513, Republic of Korea; Ohlabs Corp., Busan 48513, Republic of Korea.
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7
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Zhan X, Wang L, Gong J, Deng R, Wu M. Co-stabilization/solidification of heavy metals in municipal solid waste incineration fly ash and electrolytic manganese residue based on self-bonding characteristics. CHEMOSPHERE 2022; 307:135793. [PMID: 35872056 DOI: 10.1016/j.chemosphere.2022.135793] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 07/10/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023]
Abstract
Municipal solid waste incineration (MSWI) fly ash and electrolytic manganese residue (EMR) were classified as hazardous waste, must be harmlessly processed prior to subsequent treatment or disposal. The competition between massive free manganese ions of raw EMR and other heavy metals was found, thus raw EMR was pretreated by calcining to eliminate competition of manganese with other heavy metals for stabilizer complexation. MSWI fly ash was successfully solidified with 6% NaH2PO4, 6% H2NCSNH2 and 20% sintered EMR (800 °C). The addition of sintered EMR enhanced solidification/stabilization of heavy metals in fly ash and the resulting product had a higher compressive strength for further reutilization like trench backfilling, structural fill and void filling. The stabilization/solidification mechanism of heavy metals was attributed to the combined interaction of heavy metal precipitation in stabilizers and ion exchange or physical encapsulation in silicate compounds like calcium silicate, which is a feasible and valuable approach to co-disposal of MSWI fly ash and EMR.
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Affiliation(s)
- Xinyuan Zhan
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui, 230009, PR China; East China Engineering Science and Technology Co., LTD, Hefei, Anhui, 230009, PR China
| | - Li'ao Wang
- College of Resource and Environmental Science, Chongqing University, Chongqing, 40044, PR China.
| | - Jian Gong
- College of Resource and Environmental Science, Chongqing University, Chongqing, 40044, PR China
| | - Rui Deng
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui, 230009, PR China
| | - Meng Wu
- School of Civil Engineering and Architecture,Anhui University of Science and Technology,Huainan, Anhui, 232001, PR China
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Chen W, Wang Y, Sun Y, Fang G, Li Y. Release of soluble ions and heavy metal during fly ash washing by deionized water and sodium carbonate solution. CHEMOSPHERE 2022; 307:135860. [PMID: 35944671 DOI: 10.1016/j.chemosphere.2022.135860] [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: 01/10/2022] [Revised: 04/16/2022] [Accepted: 07/24/2022] [Indexed: 06/15/2023]
Abstract
Two municipal solid waste incineration fly ashes were selected for washing by deionized water and Na2CO3 solution for comparison. Results showed that the benefits of washing were two folds: (1) Washing was able to reduce the contents of Cl- and SO42- while increased the contents of CaO, SiO2, Al2O3 etc.; (2) Washing by Na2CO3 solution showed increased stability of heavy metals (Cr, Ni, Cd, Cu, Zn and Pb) and fly ash was safe for later reuse. Release of Cl- was high at more than 90% regardless of washing solution. SO42- and Ca2+ removal was highly dependent on the dissolution and precipitation equilibriums. Na2CO3 washing promoted the formation of CaCO3. Thus SO42- was washed off instead of precipitating as CaSO4 and retained in fly ash solid. SO42- removal was raised to more than 80% by Na2CO3 washing as compared with about 30% by deionized water. At the same time, Ca removal by Na2CO3 dropped to 1-2%. In addition, the basicity of fly ash was important as high basicity helped SO42- removal. Overall, washing by Na2CO3 appears to be a promising option for fly ash treatment.
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Affiliation(s)
- Weifang Chen
- School of Environment and Architecture, University of Shanghai for Science and Technology, 516 Jun Gong Road, Shanghai, 200093, China.
| | - Yegui Wang
- School of Environment and Architecture, University of Shanghai for Science and Technology, 516 Jun Gong Road, Shanghai, 200093, China
| | - Yimo Sun
- School of Environment and Architecture, University of Shanghai for Science and Technology, 516 Jun Gong Road, Shanghai, 200093, China
| | - Guilin Fang
- School of Environment and Architecture, University of Shanghai for Science and Technology, 516 Jun Gong Road, Shanghai, 200093, China
| | - Yonglun Li
- School of Environment and Architecture, University of Shanghai for Science and Technology, 516 Jun Gong Road, Shanghai, 200093, China
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Yan M, Jiang J, Zheng R, Yu C, Zhou Z, Hantoko D. Experimental study on the washing characteristics of fly ash from municipal solid waste incineration. WASTE MANAGEMENT & RESEARCH : THE JOURNAL OF THE INTERNATIONAL SOLID WASTES AND PUBLIC CLEANSING ASSOCIATION, ISWA 2022; 40:1212-1219. [PMID: 34967247 DOI: 10.1177/0734242x211068253] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The disposal of fly ash with high salt content has become an important bottleneck for the further application of municipal solid waste incineration (MSWI). In this study, the soluble salt content and composition of fly ash from different MSWI were analysed. The composition of fly ash was affected by incinerator type and flue gas cleaning system, especially the type of deacidification solvent. The soluble salt content in fly ash from MSW grate incinerator can be over 35.16%. Most of the soluble salt was calcium salt and chloride salt. The effect of washing parameters including liquid/solid (L/S) ratio and washing time on salt removal from fly ash were studied. Raw fly ash contained high chlorine (Cl) with the maximum of 19.83% and it can be significantly reduced by washing. Double-washing and secondary-washing had better performance than single-washing on salt removal. The secondary-washing did not only save water, but also reduced the energy cost during evaporation for crystallising soluble salt. Based on the analysis of variance (ANOVA), L/S ratio was the most principal factor for salt and Cl removal of fly ash by washing.
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Affiliation(s)
- Mi Yan
- Institute of Energy and Power Engineering, Zhejiang University of Technology, Hangzhou, China
| | - Jiahao Jiang
- Institute of Energy and Power Engineering, Zhejiang University of Technology, Hangzhou, China
| | - Rendong Zheng
- Hangzhou Linjiang Environmental Energy Co. Ltd., Hangzhou, China
| | - Caimeng Yu
- Zhejiang Zheneng Xingyuan Energy Saving Technology Co. Ltd, Hangzhou, China
| | - Zhihao Zhou
- Institute of Energy and Power Engineering, Zhejiang University of Technology, Hangzhou, China
| | - Dwi Hantoko
- Institute of Energy and Power Engineering, Zhejiang University of Technology, Hangzhou, China
- Department of Chemical Engineering, Institut Teknologi Bandung, Bandung, Indonesia
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Solidification/Stabilization of MSWI Fly Ash Using a Novel Metallurgical Slag-Based Cementitious Material. MINERALS 2022. [DOI: 10.3390/min12050599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Four industrial wastes, i.e., blast furnace slag, steel slag, desulfurization ash, and phosphoric acid sludge, were used to prepare a low-carbon binder, metallurgical slag-based cementitious material (MSCM). The feasibility of solidification/stabilization of municipal solid waste incineration (MSWI) fly ashes by MSCM were evaluated, and the immobilization mechanisms of heavy metals were proposed. The MSCM paste achieved 28-day strength of 35.2 MPa, showing its high-hydration reactivity. While the fly ash content was as high as 80 wt.%, the 28-day strength of MSCM-fly ash blocks reached 2.2 MPa, and the leaching concentrations of Pb, Zn, Cr, and Hg were much lower than the limit values of the Chinese landfill standard (GB 16889-2008). The immobilization rates of each heavy metal reached 98.75–99.99%, while four kinds of MSWI fly ashes were solidified by MSWI at fly ash content of 60 wt.%. The 28-day strength of binder-fly ash blocks had an increase of 104.92–127.96% by using MSCM to replace ordinary Portland cement (OPC). Correspondingly, the lower leachability of heavy metals was achieved by using MSCM compared to OPC. The mechanisms of solidification/stabilization treatment of MSWI fly ash by MSCM were investigated by XRD, SEM, and TG-DSC. Numerous hydrates, such as calcium silicate hydrate (C-S-H), ettringite (AFt), and Friedel’s salt, were observed in hardened MSCM-fly ash pastes. Heavy metals from both MSWI fly ash and MSCM could be effectively immobilized via adsorption, cation exchange, precipitation, and physical encapsulation.
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Zhou Y, Liao C, Shih K, Tan GYA, Su M. Incorporation of lead into pyromorphite: Effect of anion replacement on lead stabilization. WASTE MANAGEMENT (NEW YORK, N.Y.) 2022; 143:232-241. [PMID: 35286968 DOI: 10.1016/j.wasman.2022.02.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Revised: 12/25/2021] [Accepted: 02/28/2022] [Indexed: 06/14/2023]
Abstract
Previous studies demonstrate that the leaching of heavy metals in unreliable waste forms causes serious environmental pollution and health concerns. Thus, research is focused on identifying an effective, safe strategy for disposing of metal-laden solid waste such as lead (Pb). This study evaluated the effect of anion replacement in the structure of pyromorphite (Pb10(PO4)6Cl2, a common mineral phase for Pb sequestering) on Pb stabilization. Phosphate (PO43-) at the tetrahedral pyromorphite site was simultaneously replaced by silicate (SiO44-) and sulphate (SO42-) in a controlled thermal treatment. The lattice expanded with the incorporation of additional SiO44- and SO42-. Furthermore, the unit cell parameters of the solid solutions evolved linearly with an increase in the substitution degree (x in Pb10(SiO4)x(SO4)x(PO4)(6-2x)Cl2). This research also demonstrated that Pb distributed into amorphous in a PO43--deficient matrix, while asisite (Pb7SiO8Cl2) was formed when the matrix was dominated by SiO44- and SO42-. The leaching results showed the isomorphous substitution in the target system rendered the products less durable towards acidic attack. Moreover, the fully isomorphous-substituted product (x = 3) showed more than two orders of magnitude lower leaching resistance than the PO43--rich phase (x = 0). The lattice expansion, resulting from the isomorphous substitution, suggested that a lower dissolution energy was required in a PO43--deficient matrix. The leaching kinetics pointed to a product with a lower apparent activation energy in the leaching process. The findings of this study provide unique insight into the design and optimization of waste forms for the immobilization of heavy metals.
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Affiliation(s)
- Ying Zhou
- Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, HKSAR, China; Advanced Institute of Natural Sciences, Beijing Normal University at Zhuhai, Zhuhai 519087, China
| | - Changzhong Liao
- Key Laboratory of New Processing for Nonferrous Metal and Materials (Ministry of Education), School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Kaimin Shih
- Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, HKSAR, China.
| | - Giin-Yu Amy Tan
- Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, HKSAR, China
| | - Minhua Su
- Guangdong Provincial Key Laboratory of Radionuclides Pollution Control and Resources, School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, China.
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