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Mong GR, Liew CS, Chong WWF, Mohd Nor SA, Ng JH, Idris R, Chiong MC, Lim JW, Zakaria ZA, Woon KS. Environment impact and bioenergy analysis on the microwave pyrolysis of WAS from food industry: Comparison of CO 2 and N 2 atmosphere. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 319:115665. [PMID: 35842993 DOI: 10.1016/j.jenvman.2022.115665] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 05/12/2022] [Accepted: 06/30/2022] [Indexed: 06/15/2023]
Abstract
The alarming output of waste activated sludge (WAS) from industries requires proper management routes to minimize its impact on the environment during disposal. Pyrolysis is a feasible way of processing and valorizing WAS into higher-value products of alternate use. Despite extensive research into the potential of WAS through pyrolysis, the technology's long-term viability and environmental impact have yet to be fully revealed. In addition, the environmental effects of utilizing different pyrolysis atmosphere (N2 or CO2) has not been studied before, although benefits of CO2 reactivity during pyrolysis have been discovered. This study evaluates the process's environmental impact, carbon footprint, and bioenergy yield when different pyrolysis atmospheres are used. The global warming potential (GWP) for a functional unit of 1 t of dried WAS is 203.81 kg CO2 eq. The heat required during pyrolysis contributes the most (63.7%) towards GWP due to high energy usage, followed by the drying process (23.6%). Transportation contributes the most towards toxicity impact (59.3%) through dust, NOx, NH3 and SO2 emissions. The initial moisture content of raw WAS (65%) greatly impacts overall energy consumption and environmental impact. Pyrolysis in an N2 atmosphere will result in a higher overall bioenergy yield (833 kWh/tonne) and a lower carbon footprint (-1.09 kg CO2/tonne). However, when CO2 was used, the specific energy value within the biochar is higher (22.26 MJ/kg) due to enhanced carbonization. The carbon content of gas derived increased due to higher CO yield. From an energy perspective, the current setup will achieve a net positive bioenergy yield of 561 kW (CO2) and 833 kW (N2), where end products like biochar, bio-oil and gas can be used for power production. Despite the energy-intensive process, microwave pyrolysis has excellent potential to achieve a negative carbon footprint. The biochar used for soil amendment served as a good carbon sink. The utilization of CO2 as carrier gases provides a pathway to utilize anthropogenic CO2, which helps reduce global warming. This work demonstrates microwave pyrolysis as a negative emission, bioenergy-producing approach for WAS disposal and valorization.
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Affiliation(s)
- Guo Ren Mong
- School of Energy and Chemical Engineering, Xiamen University Malaysia, Jalan Sunsuria, Bandar Sunsuria, 43900, Sepang, Selangor, Malaysia.
| | - Chin Seng Liew
- Department of Fundamental and Applied Sciences, HICoE-Centre for Biofuel and Biochemical Research, Institute of Self-Sustainable Building, Universiti Teknologi PETRONAS, 32610, Seri Iskandar, Perak Darul Ridzuan, Malaysia
| | - William Woei Fong Chong
- School of Mechanical Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia; Automotive Development Centre, Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia
| | - Siti Aminah Mohd Nor
- QL Figo (Johor) Sdn Bhd, Lot 3627, Jalan Harmoni 1, Taman Harmoni, 81000, Kulai, Johor, Malaysia
| | - Jo-Han Ng
- Faculty of Engineering and Physical Sciences, University of Southampton Malaysia (UoSM), 79200, Iskandar Puteri, Johor, Malaysia
| | - Rubia Idris
- Faculty of Science and Natural Resources, Universiti Malaysia Sabah, Jalan UMS, 88400, Kota Kinabalu, Sabah, Malaysia
| | - Meng Choung Chiong
- Department of Mechanical Engineering, Faculty of Engineering, Technology & Built Environment, UCSI University, 56000, Kuala Lumpur, Malaysia
| | - Jun Wei Lim
- Department of Fundamental and Applied Sciences, HICoE-Centre for Biofuel and Biochemical Research, Institute of Self-Sustainable Building, Universiti Teknologi PETRONAS, 32610, Seri Iskandar, Perak Darul Ridzuan, Malaysia
| | - Zainul Akmar Zakaria
- School of Mechanical Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia
| | - Kok Sin Woon
- School of Energy and Chemical Engineering, Xiamen University Malaysia, Jalan Sunsuria, Bandar Sunsuria, 43900, Sepang, Selangor, Malaysia
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Yin Q, Liu M, Li Y. Desorption characteristics of phosphate and ammonium from sludge-based biochar. ENVIRONMENTAL TECHNOLOGY 2022; 43:1892-1902. [PMID: 33251969 DOI: 10.1080/09593330.2020.1858179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 11/21/2020] [Indexed: 06/12/2023]
Abstract
It is effective to adsorb phosphate and ammonium from water by sludge-based biochar, while the desorption performance has not been studied systematically. Biochar in this study was prepared through the co-pyrolysis of sludge and walnut shells to remove NH4+ and PO43- from water. The desorption characteristics of NH4+ and PO43- from the post-adsorption sludge-based biochar were investigated. The effects of the adsorption condition (concentration of adsorption solution) and desorption conditions (pH value of desorption solution and desorption temperature and time) on desorption performance were examined. Several techniques were performed to characterise the properties of the post-adsorption sludge-based biochar. The adsorption amount of the pure sewage sludge biochar (SBC) for PO43- and the biochar derived from the co-pyrolysis of sewage sludge and walnut shell with the mixing ratio of 3:1 (MBC3-1) for NH4+ were 14.19/ 23.75 mg/g and 9.28/ 16.23 mg/g, respectively, when the concentrations of the adsorbates were 100 and 500 mg/L. The desorption experiments showed that the acidic condition (pH = 2) was beneficial for PO43- and NH4+ desorption. The highest desorption ratio reached 7.58% for PO43- and 2.18% for NH4+. The desorption of PO43- was endothermic, whereas that of NH4+ was exothermic. The desorption amounts of PO43- and NH4+ decreased and increased, respectively, with the increase in desorption time. This study of the desorption characteristics of PO43- and NH4+ in sludge-based biochar provides a theoretical basis for the subsequent utilisation of sludge-based biochar.
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Affiliation(s)
- Qianqian Yin
- Department of Power Engineering, North China Electric Power University, Baoding, People's Republic of China
| | - Mengtian Liu
- Department of Power Engineering, North China Electric Power University, Baoding, People's Republic of China
| | - Yonghua Li
- Department of Power Engineering, North China Electric Power University, Baoding, People's Republic of China
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Wang M, Liu G, Wang X. Wastewater post-coagulation sludge recycled as a multifunctional adsorbent via pyrolysis enhanced in carbon dioxide (CO 2). CHEMOSPHERE 2022; 291:132964. [PMID: 34800502 DOI: 10.1016/j.chemosphere.2021.132964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 11/07/2021] [Accepted: 11/15/2021] [Indexed: 06/13/2023]
Abstract
Massive wastewater post-coagulation sludge (WPCS) generated from the tertiary treatment facilities has been regarded as an environmentally burdensome waste. Herein, to take advantage of the abundant amounts of Al/Fe (hydr)oxides, the WPCS was converted into functional char via pyrolysis under CO2 and N2 atmosphere. The higher organic matter content and porous structure of WPCS than drinking water treatment sludge made it a more suitable precursor for biochar and adsorbent production. CO2 expedited the thermolysis of the organics in WPCS and the Fe (hydr)oxides in WPCS further decreased the temperature of CO2-mediated reaction. Therefore, the corresponding products outcompeted the chars in N2, achieving ∼37% higher specific surface area, stronger aromaticity and more amorphous Al and Fe contents of 201.19 ± 2.25 and 27.03 ± 0.56 mg g-1, accompanied by more loss of surface functional groups like carboxyl and hydroxyl. Accordingly, WPCS chars under CO2 showed superior performance for removing phosphate (15.58 ± 0.19 mg g-1), along with the adsorption of heavy metal (37.17 ± 1.25 mg g-1 of Pb (II)) and dye (14.45 ± 0.11 mg g-1 of methylene blue). In sum, this study proposes a win-win strategy to convert coagulation sludges into resources and a new candidate for multifunctional adsorbent production.
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Affiliation(s)
- Mengyue Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Guoshuai Liu
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi, 214122, China
| | - Xiuheng Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China.
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Zhang Y, Qin J, Yi Y. Biochar and hydrochar derived from freshwater sludge: Characterization and possible applications. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 763:144550. [PMID: 33373787 DOI: 10.1016/j.scitotenv.2020.144550] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 12/14/2020] [Accepted: 12/15/2020] [Indexed: 06/12/2023]
Abstract
Freshwater sludge (FS) is generated in large quantities during the production of drinking water every day. It is largely underutilized, and has long been filter pressed to sludge cake and then disposed of in landfills. The search for more economical and sustainable disposal or reuse options is urgently needed. Biochar and hydrochar are increasingly popular wastes derived materials with huge potential for soil improvement, environmental remediation, and mitigation of climate change, but there is a lack of research on the production of FS derived biochar and hydrochar. In this study, biochar was produced by pyrolysis at 300, 500 or 700 °C for 1 h, and hydrochar was produced by hydrothermal carbonization (HTC) at 140, 160, 180 or 200 °C for 4 h. Proximate analyses show that the biochar has a higher carbon stability and is possibly suitable for carbon sequestration, while the hydrochar contains more labile carbon structures. The ultimate analysis indicates that the surface hydrophobicity is in the order of: biochar > hydrochar > FS. The phytotoxicity tests indicate their positive effects on germination of wheat seeds. This study provides a new treatment to reuse numerous FS and put forward the possible applications of its carbonaceous products, which is expected to facilitate a circular economy and realize the zero-waste target.
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Affiliation(s)
- Yunhui Zhang
- School of Civil and Environmental Engineering, Nanyang Technological University, 639798 Singapore, Singapore; College of Environmental Science and Engineering, Tongji University, 200092 Shanghai, China
| | - Junde Qin
- School of Civil and Environmental Engineering, Nanyang Technological University, 639798 Singapore, Singapore
| | - Yaolin Yi
- School of Civil and Environmental Engineering, Nanyang Technological University, 639798 Singapore, Singapore.
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Wang M, Bai S, Wang X. Enhanced removal of heavy metals and phosphate in stormwater filtration systems amended with drinking water treatment residual-based granules. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 280:111645. [PMID: 33246755 DOI: 10.1016/j.jenvman.2020.111645] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 10/14/2020] [Accepted: 10/22/2020] [Indexed: 06/12/2023]
Abstract
To address the clogging issues in stormwater filtration systems, a drinking water treatment residual (DWTR)-based granule (DBG) substrate was developed herein by pyrolyzing and granulating the DWTR with bentonite and corncob. Toxicity characteristic leaching procedure studies indicated that fabricating into DBG stabilized the Al and heavy metals in DWTR and restrained the leaching risk. Then the removal performance of phosphate (PO₄-P) and heavy metal ions by the DWTR and DBG was evaluated in batch and laboratory-scale column experiments. Results from batch tests showed that the amount of Pb(Ⅱ) adsorbed by DBG (18.47 ± 0.56 mg g⁻1) was approximately 2.3 times of that adsorbed by DWTR (8.05 ± 0.19 mg g⁻1), whereas the PO₄-P adsorption capacity of DBG (8.63 ± 0.24 mg g⁻1) was much lower than that of DWTR (25.33 ± 0.81 mg g⁻1). This could be ascribed to the addition of corncob and bentonite (at a mass ratio of 20% and 40% in DBG, respectively), which provided extremely high cation exchange capacity for the Pb(Ⅱ) adsorption, while no effective PO₄-P adsorption component was involved. Moreover, the pyrolysis process could improve the Pb(Ⅱ) and PO₄-P adsorption capacity of the raw-mixture by 42% and 7%, whereas granulation process decreased those of the pyrolysis-mixture by 15% and 20%, respectively, owing to the reduction of accessible surface area in the DBG. Under various stormwater runoff conditions, the involvement of DBG in stormwater filtration systems exerted consistently fancy performance of Cu(Ⅱ), Pb(Ⅱ), Cd(Ⅱ) and PO₄-P removal, with average removal rates of over 86.20% and desorption rates of less than 3.50%, indicating irreversible and strong complexion between the contaminants and DBG. The DBG column manifested good permeability and stable hydraulic conductivity (2.74-2.52 m d⁻1) over a 54-day rainfall period, which was beneficial to address the clogging issue of DWTR. Overall, this study provides an alternative pathway to enhance the hydraulic condition and treatment performance of the stormwater filtration systems for urban runoff management.
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Affiliation(s)
- Mengyue Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Shunwen Bai
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Xiuheng Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China.
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Lin J, Liao Q, Hu Y, Ma R, Cui C, Sun S, Liu X. Effects of Process Parameters on Sulfur Migration and H 2S Generation during Supercritical Water Gasification of Sludge. JOURNAL OF HAZARDOUS MATERIALS 2021; 403:123678. [PMID: 32827862 DOI: 10.1016/j.jhazmat.2020.123678] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 07/25/2020] [Accepted: 08/07/2020] [Indexed: 06/11/2023]
Abstract
The generation of sulfur-containing pollution products affects the quality of biofuels obtained from the supercritical water gasification (SCWG) of sludge. This study investigates the effects of the gasification temperature, moisture content, and reaction atmosphere on the evolution of sulfur-containing compounds. The results showed that temperature was the key parameter causing the migration of sulfur from sludge to biogas and liquid products. The sludge decomposition reaction was dominated by ionic reactions at 360 °C, while the decomposition of organic matter was converted to free radical reactions as the temperature increased from 380 °C to 440 °C. The mercaptan and thioether contents of the bio-oil decreased to 0.3% at 440 °C. Correspondingly, the concentration of H2S increased from 6.7 ppm to 38.0 ppm. The decomposition of organic sulfur with an unstable structure (S-H bond and S-C bond) was the main cause of the increase in the content of H2S. Additionally, the solubility and oxidation properties of supercritical water were extremely strong. Some sulfur-containing organic compounds were converted into SO42- via hydrolysis and oxidation reactions, forming sulfate crystals with heavy metals in the bio-char, which aided in achieving the synergistic immobilization of sulfur and heavy metals.
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Affiliation(s)
- Junhao Lin
- School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Qinxiong Liao
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Yaping Hu
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Rui Ma
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Chongwei Cui
- School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
| | - Shichang Sun
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, 518060, China; Research Center for Water Science and Environmental Engineering, Shenzhen University, 518055, China.
| | - Xiangli Liu
- Shenzhen Engineering Laboratory of Aerospace Detection and Imaging, Department of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
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Foong SY, Chan YH, Cheah WY, Kamaludin NH, Tengku Ibrahim TNB, Sonne C, Peng W, Show PL, Lam SS. Progress in waste valorization using advanced pyrolysis techniques for hydrogen and gaseous fuel production. BIORESOURCE TECHNOLOGY 2021; 320:124299. [PMID: 33129091 DOI: 10.1016/j.biortech.2020.124299] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 10/14/2020] [Accepted: 10/15/2020] [Indexed: 06/11/2023]
Abstract
Hydrogen and gaseous fuel derived from wastes have opened up promising alternative pathways for the production of renewable and sustainable fuels to substitute classical fossil energy resources that cause global warming and pollution. Existing review articles focus mostly on gasification, reforming and pyrolysis processes, with limited information on particularly gaseous fuel production via pyrolysis of various waste products. This review provides an overview on the recent advanced pyrolysis technology used in hydrogen and gaseous fuel production. The key parameters to maximize the production of specific compounds were discussed. More studies are needed to optimize the process parameters and improve the understanding of reaction mechanisms and co-relationship between these advanced techniques. These advanced techniques provide novel environmentally sustainable and commercially procedures for waste-based production of hydrogen and gaseous fuels.
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Affiliation(s)
- Shin Ying Foong
- Henan Province Engineering Research Center For Biomass Value-Added Products, School of Forestry, Henan Agricultural University, Zhengzhou 450002, China; Pyrolysis Technology Research Group, Institute of Tropical Aquaculture and Fisheries (AKUATROP), Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia
| | - Yi Herng Chan
- PETRONAS Research Sdn. Bhd. (PRSB), Lot 3288 & 3289, Off Jalan Ayer Itam, Kawasan Institusi Bangi, 43000 Kajang, Selangor, Malaysia
| | - Wai Yan Cheah
- Department of Environmental Health, Faculty of Health Sciences, MAHSA University, 42610 Jenjarom, Selangor, Malaysia
| | - Noor Haziqah Kamaludin
- Department of Environmental Health, Faculty of Health Sciences, MAHSA University, 42610 Jenjarom, Selangor, Malaysia
| | | | - Christian Sonne
- Aarhus University, Department of Bioscience, Arctic Research Centre (ARC), Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | - Wanxi Peng
- Henan Province Engineering Research Center For Biomass Value-Added Products, School of Forestry, Henan Agricultural University, Zhengzhou 450002, China
| | - Pau-Loke Show
- Department of Chemical and Environmental Engineering, Faculty of Engineering, University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor Darul Ehsan, Malaysia
| | - Su Shiung Lam
- Henan Province Engineering Research Center For Biomass Value-Added Products, School of Forestry, Henan Agricultural University, Zhengzhou 450002, China; Pyrolysis Technology Research Group, Institute of Tropical Aquaculture and Fisheries (AKUATROP), Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia.
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Kwon G, Bhatnagar A, Wang H, Kwon EE, Song H. A review of recent advancements in utilization of biomass and industrial wastes into engineered biochar. JOURNAL OF HAZARDOUS MATERIALS 2020; 400:123242. [PMID: 32585525 DOI: 10.1016/j.jhazmat.2020.123242] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/13/2020] [Accepted: 06/15/2020] [Indexed: 05/12/2023]
Abstract
For past few years, biochar has gained a great deal of attention for its versatile utility in agricultural and environmental applications. The diverse functionality and environmental-friendly nature of biochar have motivated many researchers to delve into biochar researches and spurred rapid expansion of literature in recent years. Biochar can be produced from virtually all the biomass, but the properties of biochar are highly dependent upon the types of feedstock biomass and preparation methods. The overall performances of as-prepared biochar in treating soil and water contaminants is generally inferior to activated carbon due to its lower surface area and limited functionalities. This limitation has led to many follow-up studies that focused on improving material characteristics by imparting desired functionality. Such efforts have greatly advanced knowledge to produce better-performing engineered biochar with enhanced capability and versatility. To this end, this review was prepared to compile recent advancements in fabrication and application of engineered biochar, especially with respect to the influences of biomass feedstock on the properties of biochar and the utilization of industrial wastes in fabrication of engineered biochar.
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Affiliation(s)
- Gihoon Kwon
- Department of Environment and Energy, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul05006, Republic of Korea
| | - Amit Bhatnagar
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, Fl-70211, Kuopio, Finland
| | - Hailong Wang
- Biochar Engineering Technology Research Center of Guangdong Province, School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong, 528000, China; Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province, Zhejiang A&F University, Hangzhou, Zhejiang 311300, China
| | - Eilhann E Kwon
- Department of Environment and Energy, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul05006, Republic of Korea
| | - Hocheol Song
- Department of Environment and Energy, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul05006, Republic of Korea.
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Park JH, Park YK, Kim YM. Kinetic analysis and catalytic pyrolysis of spent medicinal herb over HZSM-5 and HY. ENVIRONMENTAL RESEARCH 2020; 187:109632. [PMID: 32454307 DOI: 10.1016/j.envres.2020.109632] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/19/2020] [Accepted: 05/01/2020] [Indexed: 06/11/2023]
Abstract
In this study, the kinetic analysis on the pyrolysis of a spent medicinal herb, namely spent Achyranthes root, is performed using a thermogravimetric analyzer and a model-free kinetic analysis method, allowing the calculation of activation energy values without the assumption of kinetic model. Owing to the structural change of lignin and elimination of hemicellulose during the decoction of raw Achyranthes root, the thermogravimetric analysis results show a large difference between the derivative thermogravimetry curves of spent and raw Achyranthes roots. The average apparent activation energy value of spent Achyranthes root, obtained from the non-isothermal thermogravimetric analysis, are found to be lower than those of raw Achyranthes root. This comes as a result of the much lower content of hemicellulose in spent Achyranthes root caused by the hemicellulose elimination from raw Achyranthes root during the decoction process. The catalytic fast pyrolysis of spent Achyranthes root over HZSM5-30 (HZSM-5 with SiO2/Al2O3 = 30) and HY30 (HY with SiO2/Al2O3 = 30) was performed using a two-stage fixed-bed reactor system. The catalytic fast pyrolysis of spent Achyranthes root over both HY30 and HZSM5-30 produced the much larger amount of aromatic hydrocarbons, compared to the non-catalytic fast pyrolysis, with a parallel decrease of oxygen-containing pyrolyzates. Owing to its robust pore structure and high acidity, it was the HZSM5-30 that produced the highest quality oil during the catalytic fast pyrolysis of spent Achyranthes root, having higher selectivity of mono-aromatic hydrocarbons compared to HY30.
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Affiliation(s)
- Ji Hui Park
- Department of Environmental Engineering, University of Seoul, Seoulsiridaro 163, Seoul, Republic of Korea
| | - Y-K Park
- Department of Environmental Engineering, University of Seoul, Seoulsiridaro 163, Seoul, Republic of Korea
| | - Young-Min Kim
- Department of Environmental Engineering, Daegu University, Gyeongsan, 38453, Republic of Korea.
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Cho SH, Jung S, Park YK, Tsang YF, Ryu C, Kwon EE. Synergistic effects of CO2 on ex situ catalytic pyrolysis of lignocellulosic biomass over a Ni/SiO2 catalyst. J CO2 UTIL 2020. [DOI: 10.1016/j.jcou.2020.101182] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Granulation of Drinking Water Treatment Residues: Recent Advances and Prospects. WATER 2020. [DOI: 10.3390/w12051400] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Beneficial reuse of drinking water treatment plant residues (WTRs) has been intensively studied worldwide in the last decades, but few engineering applications can be found. The majority of WTRs were directly reused in cake form (after dewatering), e.g., alum sludge cake as main substrate used in constructed wetlands (CWs), or oven dried and ground powdery form, e.g., sorbent for pollutant removal. However, WTRs reuse in such forms has several drawbacks, i.e., difficulty of recovering and easy clogging (in CWs), which result in limited WTRs engineering applications. Granulation or pelleting could widen and be a wiser WTRs reuse route and also seems to be a promising strategy to overcome the “application bottleneck” issues. In the literature, a number of trials of WTRs granulation have been reported since 2008, including sintering ceramsite, gel entrapment and newly emerged techniques. Hence, there is a need to overlook these studies and promote WTRs granulation for further development. To this end, this review firstly provides a piece of updated comprehensive information and critical analysis regarding WTRs granulation/pelleting technology. It aims to enhance WTRs granulation studies in the developing stage and thus enlarge WTRs engineering applications.
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