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Naderi K, Kalami Yazdi MS, Jafarabadi H, Bahmanzadegan F, Ghaemi A, Mosavi MR. Modeling based on machine learning to investigate flue gas desulfurization performance by calcium silicate absorbent in a sand bed reactor. Sci Rep 2024; 14:954. [PMID: 38200150 PMCID: PMC10781758 DOI: 10.1038/s41598-024-51586-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 01/07/2024] [Indexed: 01/12/2024] Open
Abstract
Flue gas desulfurization (FGD) is a critical process for reducing sulfur dioxide (SO2) emissions from industrial sources, particularly power plants. This research uses calcium silicate absorbent in combination with machine learning (ML) to predict SO2 concentration within an FGD process. The collected dataset encompasses four input parameters, specifically relative humidity, absorbent weight, temperature, and time, and incorporates one output parameter, which pertains to the concentration of SO2. Six ML models were developed to estimate the output parameters. Statistical metrics such as the coefficient of determination (R2) and mean squared error (MSE) were employed to identify the most suitable model and assess its fitting effectiveness. The random forest (RF) model emerged as the top-performing model, boasting an R2 of 0.9902 and an MSE of 0.0008. The model's predictions aligned closely with experimental results, confirming its high accuracy. The most suitable hyperparameter values for RF model were found to be 74 for n_estimators, 41 for max_depth, false for bootstrap, sqrt for max_features, 1 for min_samples_leaf, absolute_error for criterion, and 3 for min_samples_split. Three-dimensional surface plots were generated to explore the impact of input variables on SO2 concentration. Global sensitivity analysis (GSA) revealed absorbent weight and time significantly influence SO2 concentration. The integration of ML into FGD modeling offers a novel approach to optimizing the efficiency and effectiveness of this environmentally crucial process.
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Affiliation(s)
- Kamyar Naderi
- School of Chemical, Petroleum and Gas Engineering, Iran University of Science and Technology, Narmak, Tehran, 16846, Iran
| | - Mohammad Sadegh Kalami Yazdi
- Department of Electrical Engineering, Iran University of Science and Technology, Narmak, Tehran, 16846-13114, Iran
| | - Hanieh Jafarabadi
- School of Chemical, Petroleum and Gas Engineering, Iran University of Science and Technology, Narmak, Tehran, 16846, Iran
| | - Fatemeh Bahmanzadegan
- School of Chemical, Petroleum and Gas Engineering, Iran University of Science and Technology, Narmak, Tehran, 16846, Iran
| | - Ahad Ghaemi
- School of Chemical, Petroleum and Gas Engineering, Iran University of Science and Technology, Narmak, Tehran, 16846, Iran.
| | - Mohammad Reza Mosavi
- Department of Electrical Engineering, Iran University of Science and Technology, Narmak, Tehran, 16846-13114, Iran
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Chin T, Tam IC, Yin CY. Comparison of various chemical compounds for the removal of SO 2 and NO x with wet scrubbing for marine diesel engines. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:8873-8891. [PMID: 34498182 PMCID: PMC8776685 DOI: 10.1007/s11356-021-16155-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 08/20/2021] [Indexed: 05/10/2023]
Abstract
Seawater, NaOH, NaClO, NaClO2, H2O2, and KMnO4 were used as scrubbing liquids to react with SOx and NOx separately in a customized wet scrubber. The absorption of SO2 in the aqueous phase was influenced by three factors: pH, ionic concentration, and oxidation potential. For NOx removal, the effectiveness of various chemical compounds can be ranked from least to most effective as follows: seawater, NaOH, H2O2 < NaClO < KMnO4 < NaClO2. This effectiveness was influenced by the chemical compound's ability to oxidize NO to NO2, absorb the NO2 that was formed, and retaining the nitrogen in the aqueous phase. High oxidation potential promoted the oxidation of NO to NO2 but hindered the absorption of NO2. NaClO2 was superior compared to NaClO in all three categories of oxidizing, absorption and retention. NaClO could not retain a significant amount of NO2 which it absorbed in the aqueous phase. The pH around 8 provided a good balance between oxidation versus absorption/retention and reactant utilization for the chlorine-based oxidants. KMnO4 had the lowest reactant consumption rate; only half a mole was consumed for every mole of NO removed, compared to around 2-3 mol of chlorite or 3-5 mol of hypochlorite.
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Affiliation(s)
- Terence Chin
- School of Applied Sciences, Nanyang Polytechnic, 569830, Singapore, Singapore.
- Newcastle Research & Innovation Institute, Newcastle University, Singapore, 599493, Singapore.
| | - Ivan Ck Tam
- Newcastle Research & Innovation Institute, Newcastle University, Singapore, 599493, Singapore
| | - Chun-Yang Yin
- Newcastle Research & Innovation Institute, Newcastle University, Singapore, 599493, Singapore
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Effect of Absorbents on NOx Removal through Polyvinylidene Fluoride (PVDF) Hollow Fiber Membrane Modules. INTERNATIONAL JOURNAL OF CHEMICAL ENGINEERING 2021. [DOI: 10.1155/2021/8277082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
NOx (NO and NO2) are air toxins that endanger life and represent a hazard to the environment, such as photochemical smog, global warming, acid rain, ozone depletion, and the occurrence of respiratory infections. Some technological strategies to diminish NOx emissions to meet regulations depend on two techniques: the dry process and the wet process. This study applies polyvinylidene fluoride (PVDF) hollow fiber membrane modules as a medium to remove NOx from solutions containing several absorbents such as hydrogen peroxide and nitric acid (H2O2-HNO3) solutions, sodium chlorite and sodium hydroxide (NaClO2-NaOH) solutions, and sodium chlorate and sodium hydroxide (NaClO3-NaOH) solutions. The experimental results showed that the oxidant’s strength influences NOx removal efficiency, where the absorbent solutions containing hydrogen peroxide had the highest removal efficiency as hydrogen peroxide is the most potent oxidant, followed by sodium chlorite and sodium chlorate. The three pairs of absorbents also gave a high NOx removal efficiency (above 90%), which means that all the absorbents used in the study are very potential to be used to diminish NOx via the wet process. NOx removal efficiency at the same feed gas flow rate increased as the number of fiber and absorbent concentrations is increased. However, NOx removal efficiency is reduced as the feed gas flow rate is increased at the same membrane module and absorbent concentration.
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Yuan P, Wang Z, Ahmad MS, Kong W, Ma J, Wang Z, Shen B, Ji Z. Enhanced oxidative removal of NO by UV/in situ Fenton: Factors, kinetics and simulation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 778:146202. [PMID: 34030361 DOI: 10.1016/j.scitotenv.2021.146202] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/08/2021] [Accepted: 02/25/2021] [Indexed: 06/12/2023]
Abstract
A series of experiments on the oxidative removal of NO from flue gas using a novel in situ Fenton (IF) system was performed in the presence of ultraviolet light (UV). The comparison tests revealed that the in situ Fenton system facilitated by UV (UV/IF) has a better oxidation ability of NO than that of the IF system due to the photochemical effect on the generation of oxidative species like (OH). Both of the aforementioned oxidation efficiencies were higher than that of the conventional Fenton system (CF) depending on the premix of Fe2+ and H2O2 solutions, which attribute to the improvement of (OH) yield and valid utilization with continuous addition of fresh reagents and UV radiation. In follow-up experiments, the effects of UV power, gas flow rate, reagent temperature, Fe2+/H2O2 molar ratio, initial pH, initial concentration of NO and SO2 and volume fraction O2 and CO2 on the oxidative removal of NO by UV/IF method were investigated respectively. Moreover, the results of kinetic analysis indicated that NO oxidation was confirmed to have a pseudo-first-order kinetics pattern. The rate constants decreased slightly with increasing liquid temperature, and then the apparent activation energy of NO oxidation reactions in the UV/IF system was calculated as -5.62 kJ/mol by the Arrhenius equation. Furthermore, the reaction mechanism and application prospects concerning NO oxidative removal by using the UV/IF system was speculated in brief. Finally, the computational fluid dynamics (CFD) simulations revealed that the improvement of axial and radial gas hold-up would enhance the gas-liquid contact and accelerate the oxidation reactions on the interface. In addition to reasonable control of process parameters, the optimization of reactor interior structure needs to be carried out via CFD simulation and experimental validation in future research, both are favourable to promote the NO oxidation efficiency and large-scale development of this technology.
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Affiliation(s)
- Peng Yuan
- Tianjin Key Laboratory of Clean Energy Utilization and Pollutants Control, School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China; School of Chemical Engineering & Technology, Hebei University of Technology, Tianjin 300130, PR China
| | - Zhi Wang
- Tianjin Key Laboratory of Clean Energy Utilization and Pollutants Control, School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Muhammad Sajjad Ahmad
- Tianjin Key Laboratory of Clean Energy Utilization and Pollutants Control, School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Wenwen Kong
- Tianjin Key Laboratory of Clean Energy Utilization and Pollutants Control, School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Jiao Ma
- Tianjin Key Laboratory of Clean Energy Utilization and Pollutants Control, School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Zhuozhi Wang
- Tianjin Key Laboratory of Clean Energy Utilization and Pollutants Control, School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Boxiong Shen
- Tianjin Key Laboratory of Clean Energy Utilization and Pollutants Control, School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China.
| | - Zhiyong Ji
- School of Chemical Engineering & Technology, Hebei University of Technology, Tianjin 300130, PR China.
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Valorization of Raw and Calcined Chicken Eggshell for Sulfur Dioxide and Hydrogen Sulfide Removal at Low Temperature. Catalysts 2021. [DOI: 10.3390/catal11020295] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Chicken eggshell (ES) is a waste from the food industry with a high calcium content produced in substantial quantity with very limited recycling. In this study, eco-friendly sorbents from raw ES and calcined ES were tested for sulfur dioxide (SO2) and hydrogen sulfide (H2S) removal. The raw ES was tested for SO2 and H2S adsorption at different particle size, with and without the ES membrane layer. Raw ES was then subjected to calcination at different temperatures (800 °C to 1100 °C) to produce calcium oxide. The effect of relative humidity and reaction temperature of the gases was also tested for raw and calcined ES. Characterization of the raw, calcinated and spent sorbents confirmed that calcined eggshell CES (900 °C) showed the best adsorption capacity for both SO2 (3.53 mg/g) and H2S (2.62 mg/g) gas. Moreover, in the presence of 40% of relative humidity in the inlet gas, the adsorption capacity of SO2 and H2S gases improved greatly to about 11.68 mg/g and 7.96 mg/g respectively. Characterization of the raw and spent sorbents confirmed that chemisorption plays an important role in the adsorption process for both pollutants. The results indicated that CES can be used as an alternative sorbent for SO2 and H2S removal.
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Gao F, Tang X, Yi H, Zhang B, Zhao S, Wang J, Gu T, Wang Y. NiO-Modified Coconut Shell Based Activated Carbon Pretreated with KOH for the High-Efficiency Adsorption of NO at Ambient Temperature. Ind Eng Chem Res 2018. [DOI: 10.1021/acs.iecr.8b03209] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Fengyu Gao
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, P. R. China
- Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, P. R. China
| | - Xiaolong Tang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, P. R. China
- Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, P. R. China
| | - Honghong Yi
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, P. R. China
- Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, P. R. China
| | - Bowen Zhang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, P. R. China
| | - Shunzheng Zhao
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, P. R. China
- Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, P. R. China
| | - Jiangen Wang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, P. R. China
| | - Tian Gu
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, P. R. China
| | - Yuhe Wang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, P. R. China
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Yang L, Yao L, Jiang W, Jiang X, Li J. The study on continuous denitrification, desulfurization of pyrolusite/activated coke hybrid catalyst. RSC Adv 2018. [DOI: 10.1039/c7ra11720e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The SO2 removal and regeneration of ACP improved its NO removal activity, while the denitrification had almost no effect on the desulfurization. The metal sulfate of ACP-Rn showed catalytic activity for NO reduction although there is also a reverse effect.
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Affiliation(s)
- Lin Yang
- College of Architecture and Environment
- Sichuan University
- Chengdu 610065
- P. R. China
| | - Lu Yao
- College of Architecture and Environment
- Sichuan University
- Chengdu 610065
- P. R. China
- National Engineering Research Center for Flue Gas Desulfurization
| | - Wenju Jiang
- College of Architecture and Environment
- Sichuan University
- Chengdu 610065
- P. R. China
- National Engineering Research Center for Flue Gas Desulfurization
| | - Xia Jiang
- College of Architecture and Environment
- Sichuan University
- Chengdu 610065
- P. R. China
- National Engineering Research Center for Flue Gas Desulfurization
| | - Jianjun Li
- College of Architecture and Environment
- Sichuan University
- Chengdu 610065
- P. R. China
- National Engineering Research Center for Flue Gas Desulfurization
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8
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A Review on Selective Catalytic Reduction of NOx by NH3 over Mn–Based Catalysts at Low Temperatures: Catalysts, Mechanisms, Kinetics and DFT Calculations. Catalysts 2017. [DOI: 10.3390/catal7070199] [Citation(s) in RCA: 126] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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9
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Wang L, Zhao Y, Zhang J. Comprehensive Evaluation of Mercury Photocatalytic Oxidation by Cerium-Based TiO2 Nanofibers. Ind Eng Chem Res 2017. [DOI: 10.1021/acs.iecr.6b04995] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lulu Wang
- State Key Laboratory of Coal
Combustion, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Yongchun Zhao
- State Key Laboratory of Coal
Combustion, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Junying Zhang
- State Key Laboratory of Coal
Combustion, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
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10
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Xu Q, Xiao J, Zhang J, Wei X. Experimental solubility and absorption mechanism of dilute SO2 in aqueous diethylene glycol dimethyl ether solution. KOREAN J CHEM ENG 2016. [DOI: 10.1007/s11814-016-0211-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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11
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Zhao Y, Hao R, Yuan B, Jiang J. Simultaneous removal of SO₂, NO and Hg⁰ through an integrative process utilizing a cost-effective complex oxidant. JOURNAL OF HAZARDOUS MATERIALS 2016; 301:74-83. [PMID: 26342578 DOI: 10.1016/j.jhazmat.2015.08.049] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2015] [Revised: 06/21/2015] [Accepted: 08/24/2015] [Indexed: 05/21/2023]
Abstract
A novel process of pre-oxidation combining with post-absorption to simultaneously remove SO2, NO and Hg(0) from flue gas was proposed. A vaporized complex oxidant (CO) consisted of cost-effective H2O2 and NaClO2 was prepared to oxidize Hg(0) and NO, then the oxidation products were absorbed by the Ca(OH)2 solution that was followed. For the establishment of the optimal reaction conditions, the influences of various reaction factors on the simultaneous removal of SO2, NO and Hg(0) were investigated, i.e., the molar ratio of H2O2 to NaClO2 in CO, the adding rate of CO, the pH of CO, the reaction temperature, the flue gas residence time and the coexistence gases. The experimental results indicated that the desulfurization was constant in all tests, whereas the removal of NO and Hg(0) was primarily affected by the NaClO2 addition, the adding rate of CO, the pH of CO, and the reaction temperature. Meanwhile, NO and SO2 were characterized as the promoters for the Hg(0) removal. Under the optimal reaction conditions, the best simultaneous removal efficiencies were 100% for SO2, 87% for NO and 92% for Hg(0). According to the characterizations of removal products by UV-vis, EDX, XRD, AFS and XPS, the reaction mechanism was speculated.
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Affiliation(s)
- Yi Zhao
- School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, PR China.
| | - Runlong Hao
- School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, PR China
| | - Bo Yuan
- School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, PR China
| | - Jiajun Jiang
- School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, PR China
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Han Y, Li X, Fan M, Russell AG, Zhao Y, Cao C, Zhang N, Jiang G. Abatement of SO2-NOx binary gas mixtures using a ferruginous active absorbent: Part I. Synergistic effects and mechanism. J Environ Sci (China) 2015; 30:55-64. [PMID: 25872709 DOI: 10.1016/j.jes.2014.10.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 09/29/2014] [Accepted: 10/11/2014] [Indexed: 06/04/2023]
Abstract
A novel ferruginous active absorbent, prepared by fly ash, industrial lime and the additive Fe(VI), was introduced for synchronous abatement of binary mixtures of SO2-NOx from simulated coal-fired flue gas. The synergistic action of various factors on the absorption of SO2 and NOx was investigated. The results show that a strong synergistic effect exists between Fe(VI) dose and reaction temperature for the desulfurization. It was observed that in the denitration process, the synergy of Fe(VI) dose and Ca/(S+N) had the most significant impact on the removal of NO, followed by the synergy of Fe(VI) and reaction temperature, and then the synergy of reaction temperature and flue gas humidity. A scanning electron microscope (SEM) and an accessory X-ray energy spectrometer (EDS) were used to observe the surface characteristics of the raw and spent absorbent as well as fly ash. A reaction mechanism was proposed based on chemical analysis of sulfur and nitrogen species concentrations in the spent absorbent. The Gibbs free energy, equilibrium constants and partial pressures of the SO2-NOx binary system were determined by thermodynamics.
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Affiliation(s)
- Yinghui Han
- School of Mathematics and Physics, North China Electric Power University, Baoding 071003, China; School of Energy Resources and Department of Chemical & Petroleum Engineering, University of Wyoming, Laramie, WY 82071, USA; School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Xiaolei Li
- Shanxi Electric Power Exploration & Design Institute, China's State Energy Group Co., Taiyuan 030001, China
| | - Maohong Fan
- School of Energy Resources and Department of Chemical & Petroleum Engineering, University of Wyoming, Laramie, WY 82071, USA; School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
| | - Armistead G Russell
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Yi Zhao
- School of Mathematics and Physics, North China Electric Power University, Baoding 071003, China
| | - Chunmei Cao
- School of Mathematics and Physics, North China Electric Power University, Baoding 071003, China
| | - Ning Zhang
- School of Mathematics and Physics, North China Electric Power University, Baoding 071003, China
| | - Genshan Jiang
- School of Mathematics and Physics, North China Electric Power University, Baoding 071003, China
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Zhao Y, Hao R, Guo Q. A novel pre-oxidation method for elemental mercury removal utilizing a complex vaporized absorbent. JOURNAL OF HAZARDOUS MATERIALS 2014; 280:118-126. [PMID: 25146096 DOI: 10.1016/j.jhazmat.2014.07.061] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 07/04/2014] [Accepted: 07/30/2014] [Indexed: 06/03/2023]
Abstract
A novel semi-dry integrative method for elemental mercury (Hg(0)) removal has been proposed in this paper, in which Hg(0) was initially pre-oxidized by a vaporized liquid-phase complex absorbent (LCA) composed of a Fenton reagent, peracetic acid (CH3COOOH) and sodium chloride (NaCl), after which Hg(2+) was absorbed by the resultant Ca(OH)2. The experimental results indicated that CH3COOOH and NaCl were the best additives for Hg(0) oxidation. Among the influencing factors, the pH of the LCA and the adding rate of the LCA significantly affected the Hg(0) removal. The coexisting gases, SO2 and NO, were characterized as either increasing or inhibiting in the removal process, depending on their concentrations. Under optimal reaction conditions, the efficiency for the single removal of Hg(0) was 91%. Under identical conditions, the efficiencies of the simultaneous removal of SO2, NO and Hg(0) were 100%, 79.5% and 80.4%, respectively. Finally, the reaction mechanism for the simultaneous removal of SO2, NO and Hg(0) was proposed based on the characteristics of the removal products as determined by X-ray diffraction (XRD), atomic fluorescence spectrometry (AFS), the analysis of the electrode potentials, and through data from related research references.
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Affiliation(s)
- Yi Zhao
- School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, P.R. China.
| | - Runlong Hao
- School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, P.R. China
| | - Qing Guo
- School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, P.R. China
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