1
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Pu Y, Li L, Shi X, Wang Q, Abomohra A. A comparative life cycle assessment on recycled concrete aggregates modified by accelerated carbonation treatment and traditional methods. Waste Manag 2023; 172:235-244. [PMID: 37924599 DOI: 10.1016/j.wasman.2023.10.040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 10/17/2023] [Accepted: 10/30/2023] [Indexed: 11/06/2023]
Abstract
Recycling of construction and demolition wastes contributes to achieve carbon summit and carbon neutrality early in the construction industry. Accelerated carbonation is a promising new technology for enhancing the properties of recycled concrete aggregates (RCAs) as well as mitigating global warming. This study performed a comparative life cycle assessment on RCAs modified by accelerated carbonation treatment and traditional methods. The effect of different treatment methods on environmental impacts of concrete was evaluated. The key contributors of environmental impacts for concrete incorporating carbonated RCAs were identified. Moreover, a sensitivity analysis on the transport distance of concrete incorporating carbonated RCAs was conducted. Results demonstrated that incorporating carbonated RCAs could significantly reduce the energy demand, environmental impacts and environmental cost compared with natural aggregate concrete. Accelerated carbonation treatment exhibited greater potential than the normal two-stage crushing and heating treatment in mitigating environmental burden, especially for the global warming potential. Cement production and transportation were the primary contributors to environmental impacts of concrete incorporating carbonated RCAs. Sensitivity analysis indicated incorporating carbonated RCAs as alternatives of natural aggregates contributes to lower the environmental impacts of concrete when the natural aggregates are far from urban areas while the recycling center is near the city.
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Affiliation(s)
- Yunhui Pu
- School of Architecture and Civil Engineering, Chengdu University, Chengdu 610106, China; College of Architecture and Environment, Sichuan University, Chengdu 610065, China.
| | - Lang Li
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Xiaoshuang Shi
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Qingyuan Wang
- School of Architecture and Civil Engineering, Chengdu University, Chengdu 610106, China; College of Architecture and Environment, Sichuan University, Chengdu 610065, China.
| | - Abdelfatah Abomohra
- School of Architecture and Civil Engineering, Chengdu University, Chengdu 610106, China
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2
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Sorrentino GP, Zanoletti A, Ducoli S, Zacco A, Iora P, Invernizzi CM, Di Marcoberardino G, Depero LE, Bontempi E. Accelerated and natural carbonation of a municipal solid waste incineration (MSWI) fly ash mixture: Basic strategies for higher carbon dioxide sequestration and reliable mass quantification. Environ Res 2023; 217:114805. [PMID: 36375507 DOI: 10.1016/j.envres.2022.114805] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 11/09/2022] [Accepted: 11/11/2022] [Indexed: 06/16/2023]
Abstract
The carbonation of alkaline wastes is an interesting research field that may offer opportunities for CO2 reduction. However, the literature is mainly devoted to studying different waste sequestration capabilities, with lame attention to the reliability of the data about CO2 reduction, or to the possibilities to increase the amount of absorbed CO2. In this work, for the first time, the limitation of some methods used in literature to quantify the amount of sequestered CO2 is presented, and the advantages of using suitable XRD strategies to evaluate the crystalline calcium carbonate phases are demonstrated. In addition, a zero-waste approach, aiming to stabilize the waste by coupling the use of by-products and the possibility to obtain CO2 sequestration, was considered. In particular, for the first time, the paper investigates the differences in natural and accelerated carbonation (NC and AC) mechanisms, occurring when municipal solid waste incineration (MSWI) fly ash is stabilized by using the bottom ash with the same origin, and other by-products. The stabilization mechanism was attributed to pozzolanic reactions with the formation of calcium silicate hydrates or calcium aluminate hydrate phases that can react with CO2 to produce calcium carbonate phases. The work shows that during the AC, crystalline calcium carbonate was quickly formed by the reaction of Ca(OH)2 and CaClOH with CO2. On the contrary, in NC, carbonation occurred due to reactions also with the amorphous Ca. The sequestration capability of this technology, involving the mixing of waste and by-products, is up to 165 gCO2/Kg MSWI FA, which is higher than the literature data.
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Affiliation(s)
- Giampiero P Sorrentino
- Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze, 38, Brescia, 25123, Italy; National Interuniversity Consortium of Materials Science and Technology (INSTM), R.U. Brescia, Florence, Italy.
| | - Alessandra Zanoletti
- Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze, 38, Brescia, 25123, Italy; National Interuniversity Consortium of Materials Science and Technology (INSTM), R.U. Brescia, Florence, Italy.
| | - Serena Ducoli
- Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze, 38, Brescia, 25123, Italy; National Interuniversity Consortium of Materials Science and Technology (INSTM), R.U. Brescia, Florence, Italy.
| | - Annalisa Zacco
- Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze, 38, Brescia, 25123, Italy; National Interuniversity Consortium of Materials Science and Technology (INSTM), R.U. Brescia, Florence, Italy.
| | - Paolo Iora
- Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze, 38, Brescia, 25123, Italy.
| | - Costante Mario Invernizzi
- Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze, 38, Brescia, 25123, Italy.
| | - Gioele Di Marcoberardino
- Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze, 38, Brescia, 25123, Italy.
| | - Laura E Depero
- Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze, 38, Brescia, 25123, Italy; National Interuniversity Consortium of Materials Science and Technology (INSTM), R.U. Brescia, Florence, Italy.
| | - Elza Bontempi
- Department of Mechanical and Industrial Engineering, University of Brescia, Via Branze, 38, Brescia, 25123, Italy; National Interuniversity Consortium of Materials Science and Technology (INSTM), R.U. Brescia, Florence, Italy.
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3
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Popov N, Rončević S, Duduković N, Krčmar D, Mihaljev Ž, Živkov Baloš M, Đorđievski S. Ex situ remediation of sediment from Serbia using a combination of electrokinetic and stabilization/solidification with accelerated carbonation treatments. Environ Sci Pollut Res Int 2021; 28:14969-14982. [PMID: 33222071 DOI: 10.1007/s11356-020-11621-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 11/09/2020] [Indexed: 06/11/2023]
Abstract
The application of three simple and cost-effective technologies for ex situ remediation of the sediment of Begej River in Serbia is presented in this paper. In the first step, conventional electrokinetic treatment (EK) was carried out to reduce the amount of contaminated sediment and enhance the accumulation of metals. Subsequently, stabilization/solidification (S/S) treatment was applied to the remaining portion of polluted sediment to immobilize the accumulated metals. At the same time, the influence of accelerated carbonation on the effectiveness of the treatment was evaluated. The immobilizing agents used in this study included bio ash produced by combustion of wheat and soy straw mixture and bio ash derived from molasses incineration. After the treatments, the risk assessment was performed by using the sequential extraction procedure (SEP) and TCLP and DIN 3841-4 S4 leaching tests. The results obtained after the EK treatment revealed a reduction in the amount of polluted sediment to a half. Leaching tests and SEP performed on S/S mixtures after a 28-day maturation period indicated that accelerated carbonation decreased the mobility of critical metals, especially in wheat and soy straw mixtures. Moreover, based on the leaching tests, all prepared mixtures were categorized as non-hazardous and safe for disposal according to the relevant Serbian regulations. The newly developed method that combines EK and S/S treatments with the addition of accelerated carbonation produced reduced volumes of stabilized sediment which is safe for disposal.
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Affiliation(s)
- Nenad Popov
- Faculty of Sciences, Department of Chemistry, Biochemistry and Environmental Protection, University of Novi Sad, Trg Dositeja Obradovića 3, Novi Sad, 21000, Serbia
- Scientific Veterinary Institute "Novi Sad", Rumenački put 20, Novi Sad, 21000, Serbia
| | - Srđan Rončević
- Faculty of Sciences, Department of Chemistry, Biochemistry and Environmental Protection, University of Novi Sad, Trg Dositeja Obradovića 3, Novi Sad, 21000, Serbia
| | - Nataša Duduković
- Faculty of Sciences, Department of Chemistry, Biochemistry and Environmental Protection, University of Novi Sad, Trg Dositeja Obradovića 3, Novi Sad, 21000, Serbia.
| | - Dejan Krčmar
- Faculty of Sciences, Department of Chemistry, Biochemistry and Environmental Protection, University of Novi Sad, Trg Dositeja Obradovića 3, Novi Sad, 21000, Serbia
| | - Željko Mihaljev
- Scientific Veterinary Institute "Novi Sad", Rumenački put 20, Novi Sad, 21000, Serbia
| | - Milica Živkov Baloš
- Scientific Veterinary Institute "Novi Sad", Rumenački put 20, Novi Sad, 21000, Serbia
| | - Stefan Đorđievski
- Mining and Metallurgy Institute Bor, Zeleni Bulevar 35, Bor, 19210, Serbia
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4
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Liu Y, Zhuge Y, Chow CWK, Keegan A, Pham PN, Li D, Qian G, Wang L. Recycling drinking water treatment sludge into eco-concrete blocks with CO 2 curing: Durability and leachability. Sci Total Environ 2020; 746:141182. [PMID: 32768782 DOI: 10.1016/j.scitotenv.2020.141182] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 07/18/2020] [Accepted: 07/21/2020] [Indexed: 06/11/2023]
Abstract
Drinking water treatment sludge (DWTS) can be recycled into low-strength concrete blocks for construction use. The sodium sulfate resistance and leaching behaviours of the DWTS-derived blocks are investigated in this study. The experimental results show that the addition of DWTS degrades the sodium sulfate resistance of the concrete blocks, however CO2 curing compensates for such property, especially in the case of blocks incorporating 30% DWTS. The improvement can be attributed to the formation of crystalline CaCO3 during CO2 curing for microstructure refinement evidenced by X-ray Computed Tomography and Scanning Electron Microscopy. Leaching analyses show that Cu and Al concentrations increased with increasing DWTS content, and CO2 curing adversely increased the leachability of metals due to the decrease of pH, especially at early leaching stage. Nevertheless, the total leaching concentrations of Cu and Al after 60-day test is far below the prescribed limitations, regardless of samples subject to air curing or CO2 curing. In summary, sludge-derived blocks exposed to CO2 curing are safe and behave well in aggressive environments. Therefore, this study showcases a green technology that successfully recycling DWTS into value-added and durable concrete blocks with low environmental impacts.
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Affiliation(s)
- Yue Liu
- STEM, University of South Australia, Mawson Lakes, SA 5095, Australia
| | - Yan Zhuge
- STEM, University of South Australia, Mawson Lakes, SA 5095, Australia.
| | - Christopher W K Chow
- STEM, University of South Australia, Mawson Lakes, SA 5095, Australia; Future Industries Institute, University of South Australia, Mawson Lakes, SA 5095, Australia
| | - Alexandra Keegan
- South Australian Water Corporation, Adelaide, SA 5000, Australia
| | - Phuong Ngoc Pham
- STEM, University of South Australia, Mawson Lakes, SA 5095, Australia; Faculty of Bridge and Road Engineering, The University of Danang-University of Science and Technology, 54 Nguyen Luong Bang Str., Da Nang, Viet Nam
| | - Danda Li
- STEM, University of South Australia, Mawson Lakes, SA 5095, Australia
| | - Gujie Qian
- College of Science and Engineering, Flinders University, Bedford Park, SA 5042, Australia
| | - Lei Wang
- Institute of Construction Materials, Technische Universität Dresden, 01062 Dresden, Germany.
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5
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Brück F, Ufer K, Mansfeldt T, Weigand H. Continuous-feed carbonation of waste incinerator bottom ash in a rotating drum reactor. Waste Manag 2019; 99:135-145. [PMID: 31476638 DOI: 10.1016/j.wasman.2019.08.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 08/12/2019] [Accepted: 08/16/2019] [Indexed: 06/10/2023]
Abstract
Carbonation is a key process in the aging of waste incinerator bottom ash (BA). The reaction with CO2 decreases the BA alkalinity and lowers the leachability of amphoteric trace metals. Passive ageing over several months is usually performed in intermittently mixed BA heaps. Here we aimed at accelerating the process in a rotating drum reactor continuously fed with the BA and the reactant gas (10 vol-% CO2, volumetric flow rate 60 L/min). In one test, the gas was heated and humidified. Since carbonation depends on the specific CO2-supply, experiments were conducted at varied BA residence time (60, 80, and 100 min). Residence time was calculated by mass balancing and confirmed by the breakthrough time of two tracers. Leachates and solid phase properties of the treated BA served to evaluate the carbonation performance. The residence time of BA could be adequately controlled by the reactor loading and feed rate. A residence time of 80 min was sufficient to reduce the BA leachability such as to comply with the German regulatory standards for non-hazardous waste, whereas the untreated BA was hazardous waste. Decreased alkalinity was indicated by lower leachate pH and Ca(OH)2 contents of the BA as compared to the input. Leachate concentrations of amphoteric trace metals (Pb, Zn, Cu) decreased by at least one order of magnitude while oxyanions became slightly more mobile upon carbonation. In view of relatively short residence times and stable process performance, the rotating drum reactor seems promising for a full-scale implementation of BA carbonation.
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Affiliation(s)
- Felix Brück
- Competence Centre for Energy and Environmental Engineering, THM University of Applied Sciences, Wiesenstr. 14, 35390 Gießen, Germany.
| | - Kristian Ufer
- Federal Institute for Geosciences and Natural Resources, Technical Mineralogy and Clay Mineralogy, 30655 Hannover, Germany
| | - Tim Mansfeldt
- University of Cologne, Faculty of Mathematics and Natural Sciences, Department of Geosciences, Institute of Geography, Albertus-Magnus-Platz, 50923 Köln, Germany
| | - Harald Weigand
- Competence Centre for Energy and Environmental Engineering, THM University of Applied Sciences, Wiesenstr. 14, 35390 Gießen, Germany
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6
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Chen TL, Fang YK, Pei SL, Pan SY, Chen YH, Chiang PC. Development and deployment of integrated air pollution control, CO 2 capture and product utilization via a high-gravity process: comprehensive performance evaluation. Environ Pollut 2019; 252:1464-1475. [PMID: 31265957 DOI: 10.1016/j.envpol.2019.06.047] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 06/11/2019] [Accepted: 06/11/2019] [Indexed: 06/09/2023]
Abstract
In this study, a proposed integrated high-gravity technology for air pollution control, CO2 capture, and alkaline waste utilization was comprehensively evaluated from engineering, environmental, and economic perspectives. After high-gravity technology and coal fly ash (CFA) leaching processes were integrated, flue gas air emissions removal (e.g., sulfate dioxide (SO2), nitrogen oxides (NOx), total suspended particulates (TSP)) and CO2 capture were studied. The CFA, which contains calcium oxide and thus, had high alkalinity, was used as an absorbent in removing air pollution residues. To elucidate the availability of technology for pilot-scale high-gravity processes, the engineering performance, environmental impact, and economic cost were simultaneously investigated. The results indicated that the maximal CO2, SO2, NOx, and TSP removal efficiencies of 96.3 ± 2.1%, 99.4 ± 0.3%, 95.9 ± 2.1%, and 83.4 ± 2.6% were respectively achieved. Moreover, a 112 kWh/t-CO2 energy consumption for a high-gravity process was evaluated, with capture capacities of 510 kg CO2 and 0.468 kg NOx per day. In addition, the fresh, water-treated, acid-treated, and carbonated CFA was utilized as supplementary cementitious materials in the blended cement mortar. The workability, durability, and compressive strength of 5% carbonated CFA blended into cement mortar showed superior performance, i.e., 53 MPa ±2.5 MPa at 56 days. Furthermore, a higher engineering performance with a lower environmental impact and lower economic cost could potentially be evaluated to determine the best available operating condition of the high-gravity process for air pollution reduction, CO2 capture, and waste utilization.
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Affiliation(s)
- Tse-Lun Chen
- Graduate Institute of Environmental Engineering, National Taiwan University, No. 71, Chou-Shan Road, Taipei City, 10673, Taiwan
| | - Yun-Ke Fang
- Graduate Institute of Environmental Engineering, National Taiwan University, No. 71, Chou-Shan Road, Taipei City, 10673, Taiwan
| | - Si-Lu Pei
- R&D Institute, China Tianying Inc., 2555 Xiu-Pu Road, Pu Dong New District, Shanghai City, 200120, China
| | - Shu-Yuan Pan
- Department of Bioenvironmental Systems Engineering, National Taiwan University, 1, Sec. 4, Roosevelt Road, Da-an District, Taipei City, 10617, Taiwan
| | - Yi-Hung Chen
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, No. 1, Section 3, Zhongxiao E. Road, Taipei City, 10608, Taiwan
| | - Pen-Chi Chiang
- Graduate Institute of Environmental Engineering, National Taiwan University, No. 71, Chou-Shan Road, Taipei City, 10673, Taiwan; Carbon Cycle Research Center, National Taiwan University, No. 71, Fang-Lan Road, Taipei City, 10674, Taiwan.
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7
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Chen B, Yoon S, Zhang Y, Han L, Choi Y. Reduction of steel slag leachate pH via humidification using water and aqueous reagents. Sci Total Environ 2019; 671:598-607. [PMID: 30933816 DOI: 10.1016/j.scitotenv.2019.03.362] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 03/16/2019] [Accepted: 03/22/2019] [Indexed: 06/09/2023]
Abstract
A slag humidification process that aims to reduce the leachate pH of steel slag via carbonation was accomplished by simply wetting the slag and exposing it to the atmosphere for passive diffusion of atmospheric CO2. The optimization parameters of the process were studied. Results showed that by wetting the slag using various aqueous solutions (deionized water, NaCl solution and NaOH solution), such that its moisture content nearly reaches its water holding capacity, a significant reduction in leachate pH could be achieved. Pretreatment of the slag using 1 M NaOH and subsequent humidification using deionized water showed the best efficiency of 1.1 pH unit reduction among the tested conditions. Slag pretreatment could substantially enhance the carbonation degree on the slag surface, leading to conservation of the treatment effectiveness up to three times the leachate replenishment using deionized water. The benefit of the alkaline treatment to promote slag carbonation could also be achieved using a low to moderate (0.005-0.1 M) NaOH solutions for humidification without the pretreatment step. A 72.5% increase in the treatment efficiency could be achieved via a humidification treatment using 0.005 M NaOH solution compared to that using deionized water. This study shows the promise of humidification treatment as a low-cost, easily implemented, and environmentally friendly slag pH neutralization process that can be applied in the field for slag treatment prior to its use or disposal in the environment.
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Affiliation(s)
- Bo Chen
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, China; Department of Civil and Environmental Engineering, Seoul National University, Seoul, Republic of Korea
| | - Sangwon Yoon
- Department of Civil and Environmental Engineering, Seoul National University, Seoul, Republic of Korea
| | - Yi Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, China
| | - Longxi Han
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, China
| | - Yongju Choi
- Department of Civil and Environmental Engineering, Seoul National University, Seoul, Republic of Korea; Institute of Construction and Environmental Engineering, Seoul National University, Seoul, Republic of Korea.
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Lombardi L, Costa G, Spagnuolo R. Accelerated carbonation of wood combustion ash for CO 2 removal from gaseous streams and storage in solid form. Environ Sci Pollut Res Int 2018; 25:35855-35865. [PMID: 29748811 DOI: 10.1007/s11356-018-2159-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 04/26/2018] [Indexed: 06/08/2023]
Abstract
In this work, ash generated by the combustion of wood in a central heating plant was used to remove and permanently store by accelerated carbonation CO2 contained in a gas mixture simulating biogas. The process was studied as an alternative treatment to the ones currently available on the market for biogas upgrading. The process was investigated at laboratory scale by setting up a facility for directly contacting the wood ash and the synthetic biogas in a fixed bed reactor. The process was able to completely remove CO2 during its initial phase. After about 30 h, CO2 started to appear again in the outlet stream and its concentration rapidly increased. The specific CO2 uptake achieved in solid carbonate form was of about 200 g/kg of dry wood ash. This value is an order of magnitude higher than the ones found for waste incineration bottom ash carrying out similar experiments. The difference was ascribed to the physicochemical properties of the ash, characterized by a fine particle size (d50 < 0.2 mm) and high content of reactive phases with CO2 (e.g., Ca hydroxides). The leaching behavior of the wood ash was examined before and after the accelerated carbonation process showing that the release of several elements was lower after the treatment; Ba leaching in particular decreased by over two orders of magnitude. However, the release of the critical elements for the management of this type of residues (especially Cr and sulfates) appeared not to be significantly affected, while V leaching increased.
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Affiliation(s)
- Lidia Lombardi
- Niccolò Cusano University, via don Carlo Gnocchi 3, 00166, Rome, Italy.
| | - Giulia Costa
- Department of Civil Engineering and Computer Science Engineering, University of Roma Tor Vergata, via del Politecnico 1, 00133, Rome, Italy
| | - Riccardo Spagnuolo
- Department of Civil Engineering and Computer Science Engineering, University of Roma Tor Vergata, via del Politecnico 1, 00133, Rome, Italy
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9
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Brück F, Fröhlich C, Mansfeldt T, Weigand H. A fast and simple method to monitor carbonation of MSWI bottom ash under static and dynamic conditions. Waste Manag 2018; 78:588-594. [PMID: 32559949 DOI: 10.1016/j.wasman.2018.06.042] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 05/22/2018] [Accepted: 06/19/2018] [Indexed: 06/11/2023]
Abstract
Accelerated carbonation may be employed to improve the leaching behaviour and the geotechnical properties of MSWI bottom ash (BA). Here we report on a novel method to monitor and evaluate the progress of carbonation in both static and dynamic reactor systems. The method is based on following the pressure drop in the gas phase induced by the CO2-uptake of BA and was benchmarked against carbonate contents as measured by thermogravimetry. Laboratory results demonstrated the serviceability and reproducibility of the method. Complementary logging of relative humidity and temperature showed constant moisture conditions and self-heating induced by the exothermal carbonation reaction, respectively. Under dynamic conditions BA carbonation was higher than in the static reactor. Consistently, the self-heating was more pronounced. After a reaction time of 120 min the pressure records indicated a CO2-uptake of 1.5 g CO2/100 g BA (static tests) and of 2.6 g CO2/100 g BA (dynamic tests). The proposed method is suited to study carbonation processes at minimum analytical expense and integrates over the small-scale heterogeneity of BA.
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Affiliation(s)
- Felix Brück
- ZEuUS, THM University of Applied Sciences, Wiesenstr. 14, 35390 Gießen, Germany.
| | - Christine Fröhlich
- Department MNI, THM University of Applied Sciences, Wiesenstr. 14, 35390 Gießen, Germany
| | - Tim Mansfeldt
- Soil Geography/Soil Science, Department of Geosciences, University of Cologne, Albertus-Magnus-Platz, 50923 Cologne, Germany
| | - Harald Weigand
- ZEuUS, THM University of Applied Sciences, Wiesenstr. 14, 35390 Gießen, Germany
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10
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Hwang KY, Kim JY, Phan HQH, Ahn JY, Kim TY, Hwang I. Effect of CO 2 concentration on strength development and carbonation of a MgO-based binder for treating fine sediment. Environ Sci Pollut Res Int 2018; 25:22552-22560. [PMID: 29808408 DOI: 10.1007/s11356-018-2338-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 05/15/2018] [Indexed: 06/08/2023]
Abstract
We previously described a MgO-based binder for treating fine sediment and simultaneously store CO2. Here, we describe a study of the physical/mechanical characteristics and carbonation reactions of the MgO-based binder used to solidify/stabilize fine sediment in atmospheres containing different CO2 concentrations. Carbonation of the sediment treated with the MgO-based binder at the atmospheric CO2 concentration markedly improved the compressive strength of the product. The compressive strength was 4.78 MPa after 365 days of curing, 1.3 times higher than the compressive strength of sediment treated with portland cement. This improvement was caused by the formation of carbonation products, such as hydromagnesite, nesquehonite, and lansfordite, and the constant high pH (~ 12) of the specimen, which favored the growth of hydration products such as calcium silicate hydrates and portlandite. Very low compressive strengths were found when 50 and 100% CO2 atmospheres were used because of excessive formation of carbonation products, which occupied 78% of the specimen depth. Abundant carbonation products increased the specimen volume and decreased the pH to 10.2, slowing the growth of hydration products. The absence of brucite in specimens produced in a 100% CO2 atmosphere indicated that MgO carbonation is favored over hydration at high CO2 concentrations.
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Affiliation(s)
- Kyung-Yup Hwang
- Technology Research Institute, Suntech Engineering Co., Ltd., 606, 303 Daedong-Ro, Sasang-Gu, Busan, 46981, Korea
| | - Jin Young Kim
- School of Civil and Environmental Engineering, Pusan National University, 30 Jangjeon-Dong, Geumjeong-Gu, Busan, 609-735, South Korea
| | - Hoang Quang Huy Phan
- School of Civil and Environmental Engineering, Pusan National University, 30 Jangjeon-Dong, Geumjeong-Gu, Busan, 609-735, South Korea
| | - Jun-Young Ahn
- School of Civil and Environmental Engineering, Pusan National University, 30 Jangjeon-Dong, Geumjeong-Gu, Busan, 609-735, South Korea
| | - Tae Yoo Kim
- School of Civil and Environmental Engineering, Pusan National University, 30 Jangjeon-Dong, Geumjeong-Gu, Busan, 609-735, South Korea
| | - Inseong Hwang
- School of Civil and Environmental Engineering, Pusan National University, 30 Jangjeon-Dong, Geumjeong-Gu, Busan, 609-735, South Korea.
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11
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Du B, Zhou C, Dan Z, Zhao Z, Peng X, Liu J, Duan N. Aging of solidified/stabilized electrolytic manganese solid waste with accelerated carbonation and aging inhibition. Environ Sci Pollut Res Int 2016; 23:24195-24204. [PMID: 27646448 DOI: 10.1007/s11356-016-7635-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 09/07/2016] [Indexed: 06/06/2023]
Abstract
High concentrations of soluble Mn in electrolytic manganese solid waste (EMSW) in soil cause the severe contamination in China. Calcium oxide and magnesium oxide-dominated stabilizers are suitable for the solidification/stabilization (s/s) of EMSW. However, the long-term performance of s/s using those two types of stabilizer is problematic. The aim of this study was to develop an accelerated aging method to simulate the long-term natural carbonation of solidified/stabilized EMSW. The joint use of accelerated carbonation, leaching test, mineralogical analysis, and microstructural observation was applied to assess the long-term performance of the s/s EMSW system. On an accelerated carbonation test for solidified/stabilized EMSW, an increase in Mn leaching from 13.6 to 408 mg/kg and a 1.5-2.3 decrease in pH was achieved by using CaO-dominated stabilizers, while an increase in manganese (Mn) from 30 to 266 mg/kg and a decrease in pH of 0.17-0.68 was seen using MgO-dominated stabilizers. CaO+Na3PO4 and CaO+CaCO3 were exceptions in that the leaching value of soluble Mn was lower after carbonation. Mineralogical analysis showed that rhodochrosite in the carbonated s/s system was generated not only from the reduction of hausmannite but also from the reversible reaction between Mn(OH)2 and MnCO3. Carbonation destroyed the tight particle structure resulting in a porous and loose structure. As for s/s EMSW treated by MgO-dominated stabilizers, carbonation affected the agglomerating structure and mineralogical composition by increasing magnesium (Mg) migration, thereby forming hydromagnesite that had weak binding ability and a nested porous shape. Therefore, carbonation by itself does not cause deterioration to s/s products of the soluble Mn but does have significant effects on the microstructure and mineralogical composition. It is recommended to add Na3PO4 or CaCO3 into a single CaO stabilized EMSW system to prevent aging of the system, allow formation of Mn phosphate precipitates, and improve the absorption and oxidation of soluble Mn(II).
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Affiliation(s)
- Bing Du
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, People's Republic of China
- Technology Center for Heavy Metal Cleaner Production Engineerings, Chinese Research Academy of Environmental Sciences, Beijing, People's Republic of China
- Key Laboratory for Solid Waste Management and Environment Safety, School of Environment, Tsinghua University, Beijing, People's Republic of China
| | - Changbo Zhou
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, People's Republic of China.
| | - Zhigang Dan
- Technology Center for Heavy Metal Cleaner Production Engineerings, Chinese Research Academy of Environmental Sciences, Beijing, People's Republic of China
| | - Zhiyuan Zhao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, People's Republic of China
| | - Xianjia Peng
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Jianguo Liu
- Key Laboratory for Solid Waste Management and Environment Safety, School of Environment, Tsinghua University, Beijing, People's Republic of China
| | - Ning Duan
- Technology Center for Heavy Metal Cleaner Production Engineerings, Chinese Research Academy of Environmental Sciences, Beijing, People's Republic of China
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12
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Lombardi L, Carnevale EA, Pecorini I. Experimental evaluation of two different types of reactors for CO 2 removal from gaseous stream by bottom ash accelerated carbonation. Waste Manag 2016; 58:287-298. [PMID: 27693482 DOI: 10.1016/j.wasman.2016.09.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Revised: 09/26/2016] [Accepted: 09/26/2016] [Indexed: 06/06/2023]
Abstract
Low methane content landfill gas may be enriched by removing carbon dioxide. An innovative process, based on carbon dioxide capture and storage by means of accelerated carbonation of bottom ash is proposed and studied for the above purpose. Within this research framework we devoted a preliminary research activity to investigate the possibility of improving the way the contact between bottom ash and landfill gas takes place: this is the scope of the work reported in this paper. Two different types of reactors - fixed bed and rotating drum - were designed and constructed for this purpose. The process was investigated at laboratory scale. As the aim of this phase was the comparison of the performances of the two different reactors, we used a pure stream of CO2 to preliminarily evaluate the reactor behaviors in the most favorable condition for the process (i.e. maximum CO2 partial pressure at ambient condition). With respect to the simple fixed bed reactor concept, some modifications were proposed, consisting of separating the ash bed in three layers. With the three layer configuration we would like to reduce the possibility for the gas to follow preferential paths through the ash bed. However, the results showed that the process performances are not significantly influenced by the multiple layer arrangement. As an alternative to the fixed bed reactor, the rotating drum concept was selected in order to provide continuous mixing of the solids. Two operating parameters were considered and varied during the tests: the filling ratio and the rotating speed. Better performances were observed for lower filling ratio while the rotating speed showed minor importance. Finally the performances of the two reactors were compared. The rotating drum reactor is able to provide improved carbon dioxide removal with respect to the fixed bed one, especially when the rotating reactor is operated at low filling ratio values and slow rotating speed values. Comparing the carbon dioxide specific removal obtained by using the rotating reactor (35-37g/kgBA), in the best operating conditions, with that measured for the fixed bed reactor (21-23g/kgBA), an increase of about 61-66% is observed.
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Affiliation(s)
- L Lombardi
- Niccolò Cusano University, via Don Carlo Gnocchi 3, 00166 Rome, Italy.
| | - E A Carnevale
- Industrial Engineering Department, University of Florence, via Santa Marta 3, 50139 Florence, Italy
| | - I Pecorini
- Industrial Engineering Department, University of Florence, via Santa Marta 3, 50139 Florence, Italy
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13
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Wang L, Chen Q, Jamro IA, Li R, Li Y, Li S, Luan J. Geochemical modeling and assessment of leaching from carbonated municipal solid waste incinerator (MSWI) fly ash. Environ Sci Pollut Res Int 2016; 23:12107-12119. [PMID: 26965281 DOI: 10.1007/s11356-016-6320-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 02/16/2016] [Indexed: 06/05/2023]
Abstract
Municipal solid waste incinerator (MSWI) fly ashes are characterized by high calcium oxide (CaO) content. Carbon dioxide (CO2) adsorption by MSWI fly ash was discussed based on thermogravimetry (TG)/differential thermal analysis (DTA), minerology analysis, and adapting the Stenoir equation. TG/DTA analysis showed that the weight gain of the fly ash below 440 °C was as high as 5.70 %. An adapted Stenoir equation for MSWI fly ash was discussed. The chloride in MSWI fly ash has a major impact on CO2 adsorption by MSWI fly ash or air pollution control (APC) residues. Geochemical modeling of the critical trace elements copper (Cu), cadmium (Cd), zinc (Zn), lead (Pb), and antimony (Sb) before and after carbonation was performed using a thermodynamic equilibrium model for solubility and a surface complexation model for metal sorption. Leaching of critical trace elements was generally found to be strongly dependent on the degree of carbonation attained, and their solubility appeared to be controlled by several minerals. Adsorption on ferrum (Fe) and aluminum (Al) colloids was also responsible for removal of the trace elements Cd, Pb, and Sb. We used Hakanson's potential ecological risk index (HPERI) to evaluate the risk of trace element leaching in general. The results demonstrate that the ecological risk showed a V-shaped dependency on pH; the optimum pH of the carbonated fly ash was found to be 10.3-11, resulting from the optimum carbonation (liquid-to-solid (L/S) ratio = 0.25, carbonation duration = ∼30-48 h). The dataset and modeling results presented here provide a contribution to assessing the leaching behavior of MSWI fly ash under a wide range of conditions.
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Affiliation(s)
- Lei Wang
- College of Energy & Environment, Shenyang Aerospace University, Shenyang, 110036, China.
- Chemical & Biological Engineering, The University of British Columbia, Vancouver, V6T 1Z3, Canada.
| | - Qi Chen
- College of Energy & Environment, Shenyang Aerospace University, Shenyang, 110036, China
| | - Imtiaz Ali Jamro
- College of Energy & Environment, Shenyang Aerospace University, Shenyang, 110036, China
| | - Rundong Li
- College of Energy & Environment, Shenyang Aerospace University, Shenyang, 110036, China
| | - Yanlong Li
- College of Energy & Environment, Shenyang Aerospace University, Shenyang, 110036, China
| | - Shaobai Li
- College of Energy & Environment, Shenyang Aerospace University, Shenyang, 110036, China
| | - Jingde Luan
- College of Energy & Environment, Shenyang Aerospace University, Shenyang, 110036, China
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14
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Nilsson M, Andreas L, Lagerkvist A. Effect of accelerated carbonation and zero valent iron on metal leaching from bottom ash. Waste Manag 2016; 51:97-104. [PMID: 26786400 DOI: 10.1016/j.wasman.2015.12.028] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 12/22/2015] [Accepted: 12/28/2015] [Indexed: 06/05/2023]
Abstract
About 85% of the ashes produced in Sweden originated from the incineration of municipal solid waste and biofuel. The rest comes from the thermal treatment of recycled wood, peat, charcoal and others. About 68% of all ashes annually produced in Sweden are used for constructions on landfills, mainly slopes, roads and embankments, and only 3% for construction of roads and working surfaces outside the landfills (SCB, 2013). Since waste bottom ash (BA) often has similar properties to crushed bedrock or gravel, it could be used for road constructions to a larger extent. However, the leaching of e.g. Cr, Cu, Mo, Pb and Zn can cause a threat to the surrounding environment if the material is used as it is. Carbonation is a commonly used pre-treatment method, yet it is not always sufficient. As leaching from aged ash is often controlled by adsorption to iron oxides, increasing the number of Fe oxide sorption sites can be a way to control the leaching of several critical elements. The importance of iron oxides as sorption sites for metals is known from both mineralogical studies of bottom ash and from the remediation of contaminated soil, where iron is used as an amendment. In this study, zero valent iron (Fe(0)) was added prior to accelerated carbonation in order to increase the number of adsorption sites for metals and thereby reduce leaching. Batch, column and pHstat leaching tests were performed and the leaching behaviour was evaluated with multivariate data analysis. It showed that leaching changed distinctly after the tested treatments, in particular after the combined treatment. Especially, the leaching of Cr and Cu clearly decreased as a result of accelerated carbonation. The combination of accelerated carbonation with Fe(0) addition reduced the leaching of Cr and Cu even further and reduced also the leaching of Mo, Zn, Pb and Cd compared to untreated BA. Compared with only accelerated carbonation, the Fe(0) addition significantly reduced the leaching of Cr, Cu and Mo. The effects of Fe(0) addition can be related to binding of the studied elements to newly formed iron oxides. The effects of Fe(0) addition were often more distinct at pH values between 7 and 9, which indicates that a single treatment with only Fe addition would be less effective and a combined treatment is recommended. The pHstat results showed that accelerated carbonation in combination with Fe(0)(0) addition widens the pH range for low solubility of about one unit for several of the studied elements. This indicates that pre-treating the bottom ash with a combination of accelerated carbonation and Fe(0) addition makes the leaching properties of the ash less sensitive to pH changes that may occur during reuse. All in all, the addition of Fe(0) in combination with carbonation could be an effective pre-treatment method for decreasing the mobility of potentially harmful components in bottom ash.
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Affiliation(s)
- M Nilsson
- Waste Science and Technology, Luleå University of Technology, 971 87 Lulea, Sweden
| | - L Andreas
- Waste Science and Technology, Luleå University of Technology, 971 87 Lulea, Sweden.
| | - A Lagerkvist
- Waste Science and Technology, Luleå University of Technology, 971 87 Lulea, Sweden
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15
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Araizi PK, Hills CD, Maries A, Gunning PJ, Wray DS. Enhancement of accelerated carbonation of alkaline waste residues by ultrasound. Waste Manag 2016; 50:121-129. [PMID: 26905698 DOI: 10.1016/j.wasman.2016.01.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 12/15/2015] [Accepted: 01/06/2016] [Indexed: 06/05/2023]
Abstract
The continuous growth of anthropogenic CO2 emissions into the atmosphere and the disposal of hazardous wastes into landfills present serious economic and environmental issues. Reaction of CO2 with alkaline residues or cementitius materials, known as accelerated carbonation, occurs rapidly under ambient temperature and pressure and is a proven and effective process of sequestering the gas. Moreover, further improvement of the reaction efficiency would increase the amount of CO2 that could be permanently sequestered into solid products. This paper examines the potential of enhancing the accelerated carbonation of air pollution control residues, cement bypass dust and ladle slag by applying ultrasound at various water-to-solid (w/s) ratios. Experimental results showed that application of ultrasound increased the CO2 uptake by up to four times at high w/s ratios, whereas the reactivity at low water content showed little change compared with controls. Upon sonication, the particle size of the waste residues decreased and the amount of calcite precipitates increased. Finally, the sonicated particles exhibited a rounded morphology when observed by scanning electron microscopy.
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Affiliation(s)
- Paris K Araizi
- Faculty of Engineering and Science, University of Greenwich, Chatham Maritime, Kent ME4 4TBUK, United Kingdom.
| | - Colin D Hills
- Faculty of Engineering and Science, University of Greenwich, Chatham Maritime, Kent ME4 4TBUK, United Kingdom
| | - Alan Maries
- Faculty of Engineering and Science, University of Greenwich, Chatham Maritime, Kent ME4 4TBUK, United Kingdom
| | - Peter J Gunning
- Faculty of Engineering and Science, University of Greenwich, Chatham Maritime, Kent ME4 4TBUK, United Kingdom
| | - David S Wray
- Faculty of Engineering and Science, University of Greenwich, Chatham Maritime, Kent ME4 4TBUK, United Kingdom
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16
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Polettini A, Pomi R, Stramazzo A. CO2 sequestration through aqueous accelerated carbonation of BOF slag: A factorial study of parameters effects. J Environ Manage 2016; 167:185-195. [PMID: 26686071 DOI: 10.1016/j.jenvman.2015.11.042] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 11/18/2015] [Accepted: 11/19/2015] [Indexed: 06/05/2023]
Abstract
A factorial study was conducted on basic oxygen furnace slag from a steelmaking industry with the aim of systematically identifying the individual and joint effects of the operating parameters (total pressure, CO2 concentration in the gas phase and temperature) on the CO2 sequestration yield of a direct aqueous carbonation process. Each operating parameter was varied over a range of three levels according to a 3(3) factorial design, resulting in 27 carbonation experiments. The carbonation performance and the changes in particle size and mineralogical characteristics of the slag were investigated in detail. The analysis of the experimental results indicated large effects of the operating factors on CO2 uptake, which was observed to span the range 6.7-53.6 g CO2/100 g slag. The best carbonation performance achieved was particularly significant compared to previous studies, even more considering the relative mild operating conditions adopted (P = 5 bar, C = 40% vol. CO2, T = 50 °C, t = 4 h). The analysis of the solid and liquid phases at the end of the carbonation treatment evidenced significant changes in the physical, chemical and mineralogical composition of the material. In particular, evidence was gained of other elements (Mg, Fe, Mn, Zn) in addition to Ca being intensively involved in the carbonation reactions, with a variety of carbonate phases being produced in addition to calcium carbonate forms.
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Affiliation(s)
- Alessandra Polettini
- Department of Civil and Environmental Engineering, University of Rome "La Sapienza", Via Eudossiana 18 - 00184, Rome, Italy.
| | - Raffaella Pomi
- Department of Civil and Environmental Engineering, University of Rome "La Sapienza", Via Eudossiana 18 - 00184, Rome, Italy.
| | - Alessio Stramazzo
- Department of Civil and Environmental Engineering, University of Rome "La Sapienza", Via Eudossiana 18 - 00184, Rome, Italy.
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17
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Costa G, Polettini A, Pomi R, Stramazzo A. Leaching modelling of slurry-phase carbonated steel slag. J Hazard Mater 2016; 302:415-425. [PMID: 26489916 DOI: 10.1016/j.jhazmat.2015.10.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 10/01/2015] [Accepted: 10/04/2015] [Indexed: 06/05/2023]
Abstract
In the present work the influence of accelerated mineral carbonation on the leaching behaviour of basic oxygen furnace steel slag was investigated. The environmental behaviour of the material as evaluated through the release of major elements and toxic metals under varying pH conditions was the main focus of the study. Geochemical modelling of the eluates was used to derive a theoretical description of the underlying leaching phenomena for the carbonated material as compared to the original slag. Among the investigated elements, Ca and Si were most appreciably affected by carbonation. A very clear effect of carbonation on leaching was observed for silicate phases, and lower-Ca/Si-ratio minerals were found to control leaching in carbonated slag eluates as compared to the corresponding untreated slag sample as a result of Ca depletion from the residual slag particles. Clear evidence was also gained of solubility control for Ca, Mg and Mn by a number of carbonate minerals, indicating a significant involvement of the original slag constituents in the carbonation process. The release of toxic metals (Zn, V, Cr, Mo) was found to be variously affected by carbonation, owing to different mechanisms including pH changes, dissolution/precipitation of carbonates as well as sorption onto reactive mineral surfaces. The leaching test results were used to derive further considerations on the expected metal release levels on the basis of specific assumptions on the relevant pH domains for the untreated and carbonated slag.
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Affiliation(s)
- G Costa
- Department of Civil Engineering and Computer Science Engineering, University of Rome "Tor Vergata", Via del Politecnico 1, 00133 Rome, Italy
| | - A Polettini
- Department of Civil and Environmental Engineering, University of Rome "La Sapienza", Via Eudossiana 18, 00184 Rome, Italy.
| | - R Pomi
- Department of Civil and Environmental Engineering, University of Rome "La Sapienza", Via Eudossiana 18, 00184 Rome, Italy
| | - A Stramazzo
- Department of Civil and Environmental Engineering, University of Rome "La Sapienza", Via Eudossiana 18, 00184 Rome, Italy
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18
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Lin WY, Heng KS, Sun X, Wang JY. Influence of moisture content and temperature on degree of carbonation and the effect on Cu and Cr leaching from incineration bottom ash. Waste Manag 2015; 43:264-272. [PMID: 26077229 DOI: 10.1016/j.wasman.2015.05.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 05/12/2015] [Accepted: 05/26/2015] [Indexed: 06/04/2023]
Abstract
This study investigated the influence of moisture content and temperature on the degree of carbonation of municipal solid waste (MSW) incineration bottom ash (IBA) from two different incineration plants in Singapore. The initial rate of carbonation was affected by the nominal moisture content used. Carbonation temperature seemed to play a part in changing the actual moisture content of IBA during carbonation, which in turn affected the degree of carbonation. Results showed that 2h of carbonation was sufficient for the samples to reach a relatively high degree of carbonation that was close to the degree of carbonation observed after 1week of carbonation. Both Cu and Cr leaching also showed significant reduction after only 2h of carbonation. Therefore, the optimum moisture content and temperature were selected based on 2h of carbonation. The optimum moisture content was 15% for both incineration plants while the optimum temperature was different for the two incineration plants, at 35°C and 50°C. The effect on Cu and Cr leaching from IBA after accelerated carbonation was evaluated as a function of carbonation time. Correlation coefficient, Pearson's R, was used to determine the dominant leaching mechanism. The reduction in Cu leaching was found to be contributed by both formation of carbonate mineral and reduction of DOC leaching. On the other hand, Cr leaching seemed to be dominantly controlled by pH.
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Affiliation(s)
- Wenlin Yvonne Lin
- School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore; Residue and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141, Singapore.
| | - Kim Soon Heng
- Residue and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141, Singapore
| | - Xiaolong Sun
- Residue and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141, Singapore
| | - Jing-Yuan Wang
- School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore; Residue and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141, Singapore.
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19
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Lin WY, Heng KS, Sun X, Wang JY. Accelerated carbonation of different size fractions of MSW IBA and the effect on leaching. Waste Manag 2015; 41:75-84. [PMID: 25892439 DOI: 10.1016/j.wasman.2015.04.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Revised: 04/01/2015] [Accepted: 04/01/2015] [Indexed: 06/04/2023]
Abstract
Accelerated carbonation has been studied as a treatment method for MSW IBA, and the main advantage is that it can shorten the treatment duration from months to days, compared to natural weathering. This study investigated the effect of accelerated carbonation on different size fractions of IBA collected from two incineration plants in Singapore. The different size fractions were ground to <425μm to minimise the influence of morphological difference on carbonation efficiency from that of chemical and mineralogical differences. Total element content was carried out for IBA collected from both incineration plants and the different size fractions. XRD was also used to analyse the mineralogical composition of IBA. Results showed that the degree of carbonation decreased as the size increased, which in turn corresponded to decreasing total Ca content and portlandite phase. The leaching behaviour of Pb, Zn, Cu, Cr and soluble constituents like DOC, Cl(-), and SO4(2-) were evaluated. It was found that carbonation resulted in the reduction of leaching of most constituents, except Cl(-) and SO4(2-). The reduction in leaching after carbonation can be attributed to the decrease in pH and formation of secondary minerals, rather than the precipitation of calcite. The research also suggested that since the leaching of soluble constituents from untreated IBA is mainly from the fine fractions and the fine fractions are more reactive to accelerated carbonation, size separation is beneficial in improving the carbonation efficiency and reducing the volume of IBA that needs to be treated, which can potentially reduce the treatment cost of IBA.
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Affiliation(s)
- Wenlin Yvonne Lin
- School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore; Residue and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141, Singapore.
| | - Kim Soon Heng
- Residue and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141, Singapore
| | - Xiaolong Sun
- Residue and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141, Singapore
| | - Jing-Yuan Wang
- School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore; Residue and Resource Reclamation Centre (R3C), Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141, Singapore.
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20
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Baciocchi R, Costa G, Polettini A, Pomi R. Effects of thin-film accelerated carbonation on steel slag leaching. J Hazard Mater 2015; 286:369-378. [PMID: 25596552 DOI: 10.1016/j.jhazmat.2014.12.059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 12/26/2014] [Accepted: 12/30/2014] [Indexed: 06/04/2023]
Abstract
This paper discusses the effects of accelerated carbonation on the leaching behaviour of two types of stainless steel slags (electric arc furnace and argon oxygen decarburisation slag). The release of major elements and toxic metals both at the natural pH and at varying pH conditions was addressed. Geochemical modelling of the eluates was used to theoretically describe leaching and derive information about mineralogical changes induced by carbonation. Among the investigated elements, Ca and Si were most appreciably affected by carbonation. A very clear effect of carbonation on leaching was observed for silicate phases; geochemical modelling indicated that the Ca/Si ratio of Ca-controlling minerals shifted from ∼ 1 for the untreated slag to 0.5-0.67 for the carbonated samples, thus showing that the carbonation process left some residual Ca-depleted silicate phases while the extracted Ca precipitated in the form of carbonate minerals. For toxic metals the changes in leaching induced by carbonation appeared to be mainly related to the resulting pH changes, which were as high as ∼ 2 orders of magnitude upon carbonation. Depending on the specific shape of the respective solubility curves, the extent of leaching of toxic metals from the slag was differently affected by carbonation.
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Affiliation(s)
- R Baciocchi
- Laboratory of Environmental Engineering, University of Rome "Tor Vergata", Via del Politecnico 1 - 00133 Rome, Italy
| | - G Costa
- Laboratory of Environmental Engineering, University of Rome "Tor Vergata", Via del Politecnico 1 - 00133 Rome, Italy
| | - A Polettini
- Department of Civil and Environmental Engineering, University of Rome "La Sapienza", Via Eudossiana 18 - 00184 Rome, Italy.
| | - R Pomi
- Department of Civil and Environmental Engineering, University of Rome "La Sapienza", Via Eudossiana 18 - 00184 Rome, Italy
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21
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Baciocchi R, Costa G, Di Gianfilippo M, Polettini A, Pomi R, Stramazzo A. Thin-film versus slurry-phase carbonation of steel slag: CO₂ uptake and effects on mineralogy. J Hazard Mater 2014; 283:302-313. [PMID: 25289564 DOI: 10.1016/j.jhazmat.2014.09.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 09/08/2014] [Accepted: 09/11/2014] [Indexed: 05/28/2023]
Abstract
The results of direct aqueous accelerated carbonation of three types of steel manufacturing residues, including an electric arc furnace (EAF) slag and two basic oxygen furnace (BOF) slags, are reported. Batch accelerated carbonation tests were conducted at different temperatures and CO2 pressures applying the thin-film route (liquid to solid, L/S, ratio=0.3L/kg) or the slurry-phase route (L/S ratio=5L/kg). The CO2 uptake strongly depended on both the slag characteristics and the process route; maximum yields of 280 (EAF), 325 (BOF1) and 403 (BOF2) gCO2/kg slag were achieved in slurry phase at T=100°C and pCO2=10 bar. Differently from previous studies, additional carbonates (other than Ca-based phases) were retrieved in the carbonated BOF slags, indicating that also Mg-, Fe- and Mn-containing phases partially reacted with CO2 under the tested conditions. The results hence show that the effects of accelerated carbonation in terms of CO2 uptake capacity, yield of mineral conversion into carbonates and mineralogy of the treated product, strongly rely on several factors. These include, above all, the mineralogy of the original material and the operating conditions adopted, which thus need specific case-by-case optimization to maximize the CO2 sequestration yield.
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Affiliation(s)
- R Baciocchi
- Laboratory of Environmental Engineering, Department of Civil Engineering and Computer Science Engineering, University of Rome "Tor Vergata", Via del Politecnico 1, 00133 Rome, Italy
| | - G Costa
- Laboratory of Environmental Engineering, Department of Civil Engineering and Computer Science Engineering, University of Rome "Tor Vergata", Via del Politecnico 1, 00133 Rome, Italy
| | - M Di Gianfilippo
- Laboratory of Environmental Engineering, Department of Civil Engineering and Computer Science Engineering, University of Rome "Tor Vergata", Via del Politecnico 1, 00133 Rome, Italy
| | - A Polettini
- Department of Civil and Environmental Engineering, University of Rome "La Sapienza", Via Eudossiana 18, 00184 Rome, Italy.
| | - R Pomi
- Department of Civil and Environmental Engineering, University of Rome "La Sapienza", Via Eudossiana 18, 00184 Rome, Italy
| | - A Stramazzo
- Department of Civil and Environmental Engineering, University of Rome "La Sapienza", Via Eudossiana 18, 00184 Rome, Italy
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22
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Mostbauer P, Lombardi L, Olivieri T, Lenz S. Pilot scale evaluation of the BABIU process--upgrading of landfill gas or biogas with the use of MSWI bottom ash. Waste Manag 2014; 34:125-33. [PMID: 24120459 DOI: 10.1016/j.wasman.2013.09.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 07/23/2013] [Accepted: 09/16/2013] [Indexed: 05/12/2023]
Abstract
Biogas or landfill gas can be converted to a high-grade gas rich in methane with the use of municipal solid waste incineration bottom ash as a reactant for fixation of CO2 and H2S. In order to verify results previously obtained at a laboratory scale with 65-90 kg of bottom ash (BA), several test runs were performed at a pilot scale, using 500-1000 kg of bottom ash and up to 9.2 Nm(3)/h real landfill gas from a landfill in the Tuscany region (Italy). The input flow rate was altered. The best process performance was observed at a input flow rate of 3.7 Nm(3)/(htBA). At this flow rate, the removal efficiencies for H2S were approximately 99.5-99%.
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Affiliation(s)
- P Mostbauer
- Institute of Waste Management, University of Natural Resources and Life Sciences, Vienna, Austria.
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23
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Mostbauer P, Lombardi L, Olivieri T, Lenz S. Pilot scale evaluation of the BABIU process--upgrading of landfill gas or biogas with the use of MSWI bottom ash. Waste Manag 2013. [PMID: 24120459 DOI: 10.1016/j.wasman.2013.09.016.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Biogas or landfill gas can be converted to a high-grade gas rich in methane with the use of municipal solid waste incineration bottom ash as a reactant for fixation of CO2 and H2S. In order to verify results previously obtained at a laboratory scale with 65-90 kg of bottom ash (BA), several test runs were performed at a pilot scale, using 500-1000 kg of bottom ash and up to 9.2 Nm(3)/h real landfill gas from a landfill in the Tuscany region (Italy). The input flow rate was altered. The best process performance was observed at a input flow rate of 3.7 Nm(3)/(htBA). At this flow rate, the removal efficiencies for H2S were approximately 99.5-99%.
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Affiliation(s)
- P Mostbauer
- Institute of Waste Management, University of Natural Resources and Life Sciences, Vienna, Austria.
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24
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Chang EE, Chen TL, Pan SY, Chen YH, Chiang PC. Kinetic modeling on CO₂ capture using basic oxygen furnace slag coupled with cold-rolling wastewater in a rotating packed bed. J Hazard Mater 2013; 260:937-946. [PMID: 23892160 DOI: 10.1016/j.jhazmat.2013.06.052] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 06/14/2013] [Accepted: 06/20/2013] [Indexed: 06/02/2023]
Abstract
In this study, direct and indirect carbonation of basic oxygen furnace slag (BOFS) coupled with cold-rolling wastewater (CRW) was carried out via a rotating packed bed (RPB). The solid products were qualitatively characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) and quantitatively analyzed with thermogravimetric analysis (TGA). The leachate was analyzed with inductively coupled plasma-optical emission spectroscopy (ICP-OES). The results indicate that the maximum achievable carbonation conversion (MACC) of BOFS was 90.7%, corresponding to a capture capacity of 0.277 g CO₂/g of BOFS, by direct carbonation with CRW under a rotation speed of 750 rpm at 30 °C for 20 min. In addition, CO₂ mass balance among the gas, liquid, and solid phases within an RPB was well-developed, with an error less than 10%, to confirm the actual CO₂ capture capacity of BOFS with precision and accuracy. Furthermore, a reaction kinetic model based on mass balance was established to determine the reaction rate constant for various liquid agents (CRW and pure water). It was concluded that co-utilization of alkaline wastes including BOFS and CRW via the RPB is a novel approach for both enhancing CO₂ capture capacity and reducing the environmental impacts of alkaline wastes.
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Affiliation(s)
- E-E Chang
- Department of Biochemistry, Taipei Medical University, Taipei, Taiwan
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