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Xu C, Luo C, Du J, Liu L, Wang J, Yuan C, Guo J. Structure characteristics and combustion kinetics of the co-pyrolytic char of rice straw and coal gangue. Sci Rep 2024; 14:16320. [PMID: 39009811 PMCID: PMC11250811 DOI: 10.1038/s41598-024-67378-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Accepted: 07/10/2024] [Indexed: 07/17/2024] Open
Abstract
Co-combustion is a technology that enables the simultaneous and efficient utilization of biomass and coal gangue (CG). Nevertheless, the factors that affect the combustibility of co-pyrolytic char, which represents the rate-determining step of the entire co-combustion process, remain unclear. This study investigates the impact of the physicochemical properties of co-pyrolytic char, including pore structure, carbon structure, and alkali metals, on the combustion characteristics. The TGA analysis indicates that the ignition and burnout temperatures of the co-pyrolytic char increase as the CG mixing ratio increases, resulting in a prolonged combustion. This is due to the fact that the carbon structure of the co-pyrolytic char becomes increasingly aromatic, accompanied by a reduction in aliphatic hydrocarbons and oxygen-containing groups as the CG mixing ratio increases. Furthermore, the high ash content of the CG is another significant factor contributing to the observed reduction in combustibility. The reaction between mullite, quartz in CG, and alkali metals in biomass results in the formation of aluminosilicate, which reduces the catalytic ability of alkali metals. Furthermore, the char combustion kinetics are analyzed by the KAS method, and the results indicate that the introduction of CG increases the activation energy of the entire char combustion process. The activation energy of the 80RS20CG is within the range of 102.22-164.99 kJ/mol, while the RS char is within the range of 89.87-144.67 kJ/mol.
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Affiliation(s)
- Chunyan Xu
- School of Materials and Environment, Guangxi Minzu University, Nanning, 530006, Guangxi, China
- Guangxi Colleges and Universities Key Laboratory of Environmental-Friendly Materials and Ecological Remediation, Nanning, 530006, Guangxi, China
| | - Chengjia Luo
- School of Materials and Environment, Guangxi Minzu University, Nanning, 530006, Guangxi, China
| | - Jun Du
- School of Materials and Environment, Guangxi Minzu University, Nanning, 530006, Guangxi, China
| | - Lang Liu
- School of Materials and Environment, Guangxi Minzu University, Nanning, 530006, Guangxi, China.
- Guangxi Key Laboratory of Advanced Structural Materials and Carbon Neutrality, Nanning, 530006, Guangxi, China.
| | - Jingjing Wang
- School of Materials and Environment, Guangxi Minzu University, Nanning, 530006, Guangxi, China
| | - Chenhong Yuan
- School of Materials and Environment, Guangxi Minzu University, Nanning, 530006, Guangxi, China
| | - Junjiang Guo
- Chemical Engineering Institute, Guizhou Institute of Technology, Guiyang, 550003, Guizhou, China
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Mao R, Shao J, Wang G, Wang F, Wang C. Thermal behavior and kinetics analysis of co-combustion of petroleum coke and paper sludge-derived hydrochar. WASTE MANAGEMENT (NEW YORK, N.Y.) 2022; 153:405-414. [PMID: 36202049 DOI: 10.1016/j.wasman.2022.09.028] [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: 11/29/2021] [Revised: 08/16/2022] [Accepted: 09/24/2022] [Indexed: 06/16/2023]
Abstract
The co-combustion reactivity and kinetics of petroleum coke (PC) and paper sludge-derived hydrochar (PS) were investigated via thermogravimetric analysis. The physical and chemical structure features were also systematically tested. The results show that the combustion process of PS could be divided into three stages, while for PC only one stage could be clarified. Due to high volatile content, developed pore structure and low carbon-order degree, the combustion reactivity of PS was higher than that of PC. Although the ignition property of the blends could be significantly improved by addition of PS, it changed little for the burnout temperature and as a result the combustion intensity was deteriorated. For the samples with addition of PS from 20 % to 80 %, the comprehensive combustion index decreased from 3.69 × 10-15 to 2.12 × 10-15. The Kissinger AkahiraSunose model-free method was used in the co-combustion reaction of PC and PS, and good fitting results were obtained. For different samples with varying addition of PS, the activation energies were in the range of 107.51-198.44 kJ/mol, with the lowest value obtained at 20 % of PS, which was also the optimum proportion for co-combustion of PC and PS.
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Affiliation(s)
- Rui Mao
- Research Institute of Iron and Steel of Jiangsu Shasteel, Zhangjiagang 215625, Jiangsu, China
| | - Jiugang Shao
- Research Institute of Iron and Steel of Jiangsu Shasteel, Zhangjiagang 215625, Jiangsu, China
| | - Guangwei Wang
- School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China.
| | - Fei Wang
- Research Institute of Iron and Steel of Jiangsu Shasteel, Zhangjiagang 215625, Jiangsu, China
| | - Chuan Wang
- Swerim AB, SE-971 25 Lulea, Sweden; Material Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
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3
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Abstract
Hydrothermal treatment can convert paper mill biological (bio-) sludge waste into more energy-dense hydrochar, which can achieve energy savings and fossil CO2 emissions reduction when used for metallurgical applications. This study assesses the basic, combustion and safety performance of bio-sludge hydrochar (BSHC) to evaluate its feasibility of use in blast furnace injection processes. When compared to bituminous and anthracite coals, BSHC has high volatile matter and ash content, and low fixed carbon content, calorific value and ignition point. The Ti and Tf values of BSHC are lower and the combustion time longer compared to coal. The R0.5 value of BSHC is 5.27 × 10−4 s−1, indicating a better combustion performance than coal. A mixture of BSHC and anthracite reduces the ignition point and improves the ignition and combustion performance of anthracite: an equal mixture of BSHC and anthracite has a R0.5 of 3.35 × 10−4 s−1. The explosiveness of BSHC and bituminous coal is 800 mm, while the explosiveness of anthracite is 0 mm. A mixture of 30% BSHC in anthracite results in a maximum explosiveness value of 10 mm, contributing to safer use of BSHC. Mixing BSHC and anthracite is promising for improving combustion performance in a blast furnace while maintaining safe conditions.
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Lu X, Xu R, Sun K, Jiang J, Sun Y, Zhang Y. Study on the Effect of Torrefaction on Pyrolysis Kinetics and Thermal Behavior of Cornstalk Based On a Combined Approach of Chemical and Structural Analyses. ACS OMEGA 2022; 7:13789-13800. [PMID: 35559163 PMCID: PMC9088946 DOI: 10.1021/acsomega.2c00047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 03/16/2022] [Indexed: 06/15/2023]
Abstract
In this study, the effects of torrefaction pretreatment on physicochemical characteristics and pyrolysis behavior of cornstalk were investigated based on the changes in its chemical and structural characteristics. The results indicated that torrefaction treatment improved the fuel properties with elevated torrefaction temperature, including the lower volatile content, higher carbon content, and higher heating value. In addition, serious torrefaction promoted complete degradation of hemicellulose, while the lignin was increased obviously. The crystallinity degree of cornstalk increased first and then reduced with the torrefaction temperature. Slight torrefaction enhanced the devolatilization and thermochemical reactivity of cornstalk, but serious torrefaction discouraged the volatile release. Kinetic parameter analysis indicated that the Ozawa-Flynn-Wall model was more accurate in calculating the activation energy, and the average activation energy gradually increased from 196.06 to 199.21, 203.17, and 217.58 kJ/mol. Furthermore, the thermodynamic parameters also showed an increasing trend with elevated torrefaction temperature. These results provide important basic data support for the thermochemical conversion of cornstalk to energy and chemicals.
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Affiliation(s)
- Xincheng Lu
- CAF;
Key Laboratory of Biomass Energy and Material, Jiangsu Province; Key
and Open Laboratory of Forest Chemical Engineering, SFA; National
Engineering Laboratory for Biomass Chemical Utilization, Institute of Chemical Industry of Forest Products, Nanjing, Jiangsu 210042, PR China
- Co-innovation
Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, Jiangsu 210042, PR China
| | - Ruting Xu
- CAF;
Key Laboratory of Biomass Energy and Material, Jiangsu Province; Key
and Open Laboratory of Forest Chemical Engineering, SFA; National
Engineering Laboratory for Biomass Chemical Utilization, Institute of Chemical Industry of Forest Products, Nanjing, Jiangsu 210042, PR China
| | - Kang Sun
- CAF;
Key Laboratory of Biomass Energy and Material, Jiangsu Province; Key
and Open Laboratory of Forest Chemical Engineering, SFA; National
Engineering Laboratory for Biomass Chemical Utilization, Institute of Chemical Industry of Forest Products, Nanjing, Jiangsu 210042, PR China
| | - Jianchun Jiang
- CAF;
Key Laboratory of Biomass Energy and Material, Jiangsu Province; Key
and Open Laboratory of Forest Chemical Engineering, SFA; National
Engineering Laboratory for Biomass Chemical Utilization, Institute of Chemical Industry of Forest Products, Nanjing, Jiangsu 210042, PR China
| | - Yunjuan Sun
- CAF;
Key Laboratory of Biomass Energy and Material, Jiangsu Province; Key
and Open Laboratory of Forest Chemical Engineering, SFA; National
Engineering Laboratory for Biomass Chemical Utilization, Institute of Chemical Industry of Forest Products, Nanjing, Jiangsu 210042, PR China
| | - Yanping Zhang
- CAF;
Key Laboratory of Biomass Energy and Material, Jiangsu Province; Key
and Open Laboratory of Forest Chemical Engineering, SFA; National
Engineering Laboratory for Biomass Chemical Utilization, Institute of Chemical Industry of Forest Products, Nanjing, Jiangsu 210042, PR China
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Wang Y, Yan B, Wang Y, Zhang J, Chen X, Bastiaans RJM. A Comparison of Combustion Properties in Biomass-Coal Blends Using Characteristic and Kinetic Analyses. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182412980. [PMID: 34948589 PMCID: PMC8701168 DOI: 10.3390/ijerph182412980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 12/04/2021] [Accepted: 12/06/2021] [Indexed: 11/16/2022]
Abstract
This paper presents comparative research on the combustion of coal, wheat, corn straw (CS), beet residues after extracting sugar (BR), and their blends, coal–corn straw blends (CCSBs), coal–wheat blends (CWBs), and coal–beet residue blends (CBRBs), using thermogravimetric (TG) analysis under 10, 20, 30, 40 and 50 °C/min. The test results indicate that CS and wheat show better combustion properties than BR, which are recommended to be used in biomass combustion. Under the heating rate of 20 °C/min, the coal has the longest thermal reaction time when compared with 10 and 30 °C/min. Adding coal to the biomass can improve the burnout level of biomass materials (BM), reduce the burning speed, and make the reaction more thorough. The authors employed the Flynn–Wall–Ozawa (FWO) method and the Kissinger–Akahira–Sunose (KAS) method to calculate kinetics parameters. It was proven that overall, the FWO method is better than the KAS method for coal, BM, and coal–biomass blends (CBBs), as it provides higher correlations in this study. It is shown that adding coal to wheat and BR decreases the activation energy and makes conversion more stable under particular α. The authors selected a wider range of biomass raw materials, made more kinds of CBB, and conducted more studies on different heating rates. This research can provide useful insights into how to choose agricultural residuals and how to use them.
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Affiliation(s)
- Yalin Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; (B.Y.); (X.C.)
- Department of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands; (Y.W.); (R.J.M.B.)
- Correspondence:
| | - Beibei Yan
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; (B.Y.); (X.C.)
- Key Laboratory of Efficient Utilization of Low and Medium Grade Energy, Ministry of Education, School of Mechanical Engineering, Tianjin University, Tianjin 300072, China
| | - Yu Wang
- Department of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands; (Y.W.); (R.J.M.B.)
| | - Jiahao Zhang
- Bahen Centre for Information Technology, Department of Computer Science, University of Toronto, 40 St. George Street, Toronto, ON M5S 2E4, Canada;
| | - Xiaozhong Chen
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; (B.Y.); (X.C.)
| | - Rob J. M. Bastiaans
- Department of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands; (Y.W.); (R.J.M.B.)
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Xu H, Cheng S, Hungwe D, Zhao Y, Yoshikawa K, Takahashi F. Co-combustion of Oil Sludge Char with Raw/Hydrothermally Treated Biomass: Interactions, Kinetics, and Mechanism Analysis. ACS OMEGA 2021; 6:24960-24972. [PMID: 34604677 PMCID: PMC8482500 DOI: 10.1021/acsomega.1c03944] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Indexed: 06/13/2023]
Abstract
Comprehensive thermochemical treatment (pyrolysis and combustion) is considered to be an efficient method for treatment of oil sludge (OS) or utilization as a heat source. However, combustion of oil sludge char (OSC), the byproduct from OS pyrolysis, is difficult and energy-consuming due to the high ash content and low heating value. In this study, co-combustion of OSC with biomass is proposed, aiming at the efficient thermal treatment with heat recovery. The thermal characteristics, kinetics, and interactive mechanisms of co-combustion of OSC with raw wood (RW) or hydrothermally treated wood (HW) employing thermogravimetric analysis were investigated. The obtained results indicated that RW blending with OSC resulted in negative interactions with decreasing the apparent activation energies (E) of RW, attributed to the inhibited diffusion of volatiles. The developed porous structure in HW effectively promoted volatile matter diffusion. Coupled with the catalytic support by metal oxides in OSC, HW blending yielded positive interactions during co-combustion despite the increased E. The results showed that diffusion models were the most efficient mechanism for OSC/RW combustion. However, chemical reactions were found to be the rate-determining steps for OSC/HW combustion. The catalytic effect of inorganic elements and their physical influence on heat and mass transfer can control the co-combustion performance of OSC and biomass. The findings could offer reference information for understanding OSC co-combustion and provide a basis for implementing and optimizing the co-combustion between biomass and ash-rich waste.
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Affiliation(s)
- Hao Xu
- Department
of Transdisciplinary Science and Engineering, School of Environment
and Society, Tokyo Institute of Technology, G5-13, 4259, Nagatsuta, Midori-ku, Yokohama 226-8503, Japan
| | - Shuo Cheng
- Department
of Energy Science and Engineering, School of Environment and Society, Tokyo Institute of Technology, S6-10, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Douglas Hungwe
- Department
of Transdisciplinary Science and Engineering, School of Environment
and Society, Tokyo Institute of Technology, G5-13, 4259, Nagatsuta, Midori-ku, Yokohama 226-8503, Japan
| | - Yueyuan Zhao
- Department
of Transdisciplinary Science and Engineering, School of Environment
and Society, Tokyo Institute of Technology, G5-13, 4259, Nagatsuta, Midori-ku, Yokohama 226-8503, Japan
| | - Kunio Yoshikawa
- Zhejiang
ECO Environmental Technology Co., Ltd, Ketai Road 149, Wangchun Industrial
Zone, Yinzhou District, Ningbo 315176, Zhejiang, China
| | - Fumitake Takahashi
- Department
of Transdisciplinary Science and Engineering, School of Environment
and Society, Tokyo Institute of Technology, G5-13, 4259, Nagatsuta, Midori-ku, Yokohama 226-8503, Japan
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7
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Evaluation of the Thermal Behavior, Synergistic Catalysis, and Pollutant Emissions during the Co-Combustion of Sewage Sludge and Coal Gasification Fine Slag Residual Carbon. Catalysts 2021. [DOI: 10.3390/catal11101142] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The conversion of solid waste into energy through combustion is sustainable and economical. This study aims to comprehensively evaluate and quantify the co-combustion characteristics, synergistic catalysis, and gaseous pollutant emission patterns of sewage sludge (SS) and coal gasification fine slag residual carbon (RC) as well as their blends through thermogravimetry coupled with mass spectrometry (TG-MS). The results showed that the co-combustion of SS and RC can not only improve the ignition and burnout property but also maintain the combustion stability and comprehensive combustion performance at a better level. The kinetic analysis results showed that a first-order chemical reaction and three-dimensional diffusion are the reaction mechanisms during the co-combustion of SS and RC. The synergistic catalysis between SS and RC can well explain the changes in activation energy and reaction mechanism. Furthermore, the blending ratio of SS is recommended to be maintained at 40% because of the lowest activation energy (Ea = 81.6 kJ/mol) and the strongest synergistic effect (Xi = 0.36). The emission of gaseous pollutants is corresponding to the primary combustion stages of SS, RC, and their blends. In co-combustion, the NH3, HCN, NOx, and SO2 emissions gradually rise with the increase of SS proportion in the blends due to the high content of organic compounds in SS.
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8
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Wang S, Zou C, Lou C, Yang H, Mei M, Jing H, Cheng S. Effects of hemicellulose, cellulose and lignin on the ignition behaviors of biomass in a drop tube furnace. BIORESOURCE TECHNOLOGY 2020; 310:123456. [PMID: 32388354 DOI: 10.1016/j.biortech.2020.123456] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 04/25/2020] [Accepted: 04/26/2020] [Indexed: 06/11/2023]
Abstract
The aim of this work was to investigate the effects of cellulose, hemicellulose and lignin on the ignition behaviors of biomass. The ignition events of three components and five types of single biomass particles were captured by a high-speed camera in a drop tube furnace with a temperature of 1273 K, and the combustion temperatures for the single biomass particles were measured by radiant energy analysis technology. The comparison of the flame images and the temperature evolution of five types of biomass with three components shows that the lignin content in the biomass particle strongly influences the ignition behaviors. The ignition mechanism of the biomass particle depends heavily on the lignin content. After homogeneous ignition, the rate of increase in the flame temperature and the char ignition of biomass are closely related to the lignin content. The ignition temperature of the biomass particle depends mainly on the cellulose component.
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Affiliation(s)
- Shusen Wang
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, PR China
| | - Chun Zou
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, PR China.
| | - Chun Lou
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, PR China
| | - Haiping Yang
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, PR China
| | - Mei Mei
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, PR China
| | - Huixiang Jing
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, PR China
| | - Sizhe Cheng
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, PR China
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Wang T, Yang Q, Wang Y, Wang J, Zhang Y, Pan WP. Arsenic release and transformation in co-combustion of biomass and coal: Effect of mineral elements and volatile matter in biomass. BIORESOURCE TECHNOLOGY 2020; 297:122388. [PMID: 31734064 DOI: 10.1016/j.biortech.2019.122388] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 11/04/2019] [Accepted: 11/05/2019] [Indexed: 06/10/2023]
Abstract
After the co-combustion of tobacco stem/black bean straw/wheat straw/millet straw/corn stalk/rice straw and coal, it was found that all tested biomass in this study could inhibit arsenic release, but only rice straw promoted arsenic release. When the acid washed biomass was mixed with coal during combustion, the release of arsenic increased. When mineral metals (Na, K, Mg, Ca, Al and Fe) and Si elements were added to the coal, the mineral metals inhibited arsenic release. However, the release of arsenic was increased when the silicon content in biomass was high. The volatiles in the biomass also promoted the release of arsenic during co-combustion. The arsenic in the ash generated from co-combustion was mainly in the sulphide-bound state. Co-combustion of biomass and coal reduced the occurrence of an exchangeable state in the ash, and also significantly reduce the possibility of leaching.
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Affiliation(s)
- Tao Wang
- Key Laboratory of Power Station Energy Transfer Conversion and System, Ministry of Education, North China Electric Power University, Beijing 102206, PR China.
| | - Qin Yang
- Key Laboratory of Power Station Energy Transfer Conversion and System, Ministry of Education, North China Electric Power University, Beijing 102206, PR China
| | - Yinghao Wang
- Key Laboratory of Power Station Energy Transfer Conversion and System, Ministry of Education, North China Electric Power University, Beijing 102206, PR China
| | - Jiawei Wang
- Key Laboratory of Power Station Energy Transfer Conversion and System, Ministry of Education, North China Electric Power University, Beijing 102206, PR China
| | - Yongsheng Zhang
- Key Laboratory of Power Station Energy Transfer Conversion and System, Ministry of Education, North China Electric Power University, Beijing 102206, PR China
| | - Wei-Ping Pan
- Key Laboratory of Power Station Energy Transfer Conversion and System, Ministry of Education, North China Electric Power University, Beijing 102206, PR China; ICSET Solutions, Bowling Green, KY 42104, USA
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10
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Tian X, Dai L, Wang Y, Zeng Z, Zhang S, Jiang L, Yang X, Yue L, Liu Y, Ruan R. Influence of torrefaction pretreatment on corncobs: A study on fundamental characteristics, thermal behavior, and kinetic. BIORESOURCE TECHNOLOGY 2020; 297:122490. [PMID: 31812595 DOI: 10.1016/j.biortech.2019.122490] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 11/21/2019] [Accepted: 11/22/2019] [Indexed: 06/10/2023]
Abstract
The effects of torrefaction pretreatment on corncobs properties and its pyrolysis kinetic parameters were investigated in this study. Proximate and ultimate analyses indicated that torrefaction increased the H/Ceff ratio and higher heating value of corncobs, and reduced its oxygen content. Although the mass yield was also reduced, the corresponding energy yield was relatively higher. The crystallinity index of biomass showed a first upward and then downward trend with the torrefaction temperature. Kinetic parameters obtained from three models indicated that both the activation energy and the pre-exponential factor increased with the elevated torrefaction temperature and it's better to calculate the activation energy by the OFW method and to use the KAS and DAEM methods to calculate the pre-exponential factor. In addition, it was found that the optimum pretreatment temperature of corncobs was 240 °C.
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Affiliation(s)
- Xiaojie Tian
- State Key Laboratory of Food Science and Technology, Engineering Research Center for Biomass Conversion, Ministry of Education, Nanchang University, Nanchang 330047, China
| | - Leilei Dai
- State Key Laboratory of Food Science and Technology, Engineering Research Center for Biomass Conversion, Ministry of Education, Nanchang University, Nanchang 330047, China; Center for Biorefining and Department of Bioproducts and Biosystems Engineering University of Minnesota, 1390 Eckles Ave., St. Paul, MN 55108, USA
| | - Yunpu Wang
- State Key Laboratory of Food Science and Technology, Engineering Research Center for Biomass Conversion, Ministry of Education, Nanchang University, Nanchang 330047, China; Center for Biorefining and Department of Bioproducts and Biosystems Engineering University of Minnesota, 1390 Eckles Ave., St. Paul, MN 55108, USA.
| | - Zihong Zeng
- State Key Laboratory of Food Science and Technology, Engineering Research Center for Biomass Conversion, Ministry of Education, Nanchang University, Nanchang 330047, China
| | - Shumei Zhang
- State Key Laboratory of Food Science and Technology, Engineering Research Center for Biomass Conversion, Ministry of Education, Nanchang University, Nanchang 330047, China
| | - Lin Jiang
- State Key Laboratory of Food Science and Technology, Engineering Research Center for Biomass Conversion, Ministry of Education, Nanchang University, Nanchang 330047, China
| | - Xiuhua Yang
- State Key Laboratory of Food Science and Technology, Engineering Research Center for Biomass Conversion, Ministry of Education, Nanchang University, Nanchang 330047, China
| | - Linqing Yue
- State Key Laboratory of Food Science and Technology, Engineering Research Center for Biomass Conversion, Ministry of Education, Nanchang University, Nanchang 330047, China
| | - Yuhuan Liu
- State Key Laboratory of Food Science and Technology, Engineering Research Center for Biomass Conversion, Ministry of Education, Nanchang University, Nanchang 330047, China; Center for Biorefining and Department of Bioproducts and Biosystems Engineering University of Minnesota, 1390 Eckles Ave., St. Paul, MN 55108, USA
| | - Roger Ruan
- State Key Laboratory of Food Science and Technology, Engineering Research Center for Biomass Conversion, Ministry of Education, Nanchang University, Nanchang 330047, China; Center for Biorefining and Department of Bioproducts and Biosystems Engineering University of Minnesota, 1390 Eckles Ave., St. Paul, MN 55108, USA
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11
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Xu MX, Wu YC, Nan DH, Lu Q, Yang YP. Effects of gaseous agents on the evolution of char physical and chemical structures during biomass gasification. BIORESOURCE TECHNOLOGY 2019; 292:121994. [PMID: 31437799 DOI: 10.1016/j.biortech.2019.121994] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 08/08/2019] [Accepted: 08/09/2019] [Indexed: 06/10/2023]
Abstract
Bio-char samples were prepared from gasification of corn straw under N2, CO2 and H2O conditions, and systematically characterized to reveal the effects of gaseous agents on the evolution of char structural features during the gasification process. The results showed that the increase of reacting temperature had positive effects on the gasification of char in both H2O and CO2 atmospheres. The evolution of char pore structures under H2O and CO2 was quite different. The formation of micropores was facilitated by CO2, while mesopores and macropores were developed more in H2O condition. Besides, char structures obtained at 800 °C were more ordered than those obtained at 600 °C. Compared with the longitudinal merging, the aromatic layers preferred to grow laterally. Moreover, the mechanisms of gasification between char and gaseous agents were different. CO2 preferred to react with amorphous carbon, while the cross-linked carbon was more likely to be consumed during char gasification with H2O.
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Affiliation(s)
- Ming-Xin Xu
- National Engineering Laboratory for Biomass Power Generation Equipment, North China Electric Power University, Beijing, China
| | - Ya-Chang Wu
- National Engineering Laboratory for Biomass Power Generation Equipment, North China Electric Power University, Beijing, China
| | - Dong-Hong Nan
- National Engineering Laboratory for Biomass Power Generation Equipment, North China Electric Power University, Beijing, China
| | - Qiang Lu
- National Engineering Laboratory for Biomass Power Generation Equipment, North China Electric Power University, Beijing, China.
| | - Yong-Ping Yang
- National Engineering Laboratory for Biomass Power Generation Equipment, North China Electric Power University, Beijing, China
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