ABSTRACT
Research of calcium carbide production is of great importance to the utilization of coal. In order to improve productivity and reduce energy consumption. The thermal system in an oxygen thermal process (OTM) calcium carbide furnace was analyzed. This work established a thermodynamic model to analyze the effects of material temperature, ash yield, fixed carbon content and heat loss on calcium carbide purity and total coke consumption. The results showed that the total coke consumption for the synthesis of 1 kg of calcium carbide decreased, the purity of calcium carbide increased, and the effect of heat loss decreased as the temperature of the material entering the reaction area increased. And the effect of coke temperature was much more important than the CaO temperature. Ash yield in the coke should not exceed 20%, otherwise, the purity of calcium carbide produced can’t satisfy the industrial requirement (acetylene productivity is 260 L/kg). In addition, the temperature of the material must be between 1151 ~ 1862°C to meet the requirements of high energy utilization.
Nomenclature
= | Enthalpy change, kJ/mol | |
= | Entropy increase, kJ/mol | |
= | Gibbs free energy, kJ/mol | |
Ci | = | The average SHC of each reactant, J·g−1·K−1 |
Cdi | = | The average SHC of each component in calcium carbide, J·g−1·K−1 |
m | = | Mass of coke,g |
mi | = | Mass of each reactant,g |
mdi | = | Mass of each component in calcium carbide,g |
Mc | = | The relative atomic mass of carbon,g/mol |
∆Hco | = | The heat of generation of CO,kJ/mol |
∆H298 | = | The heat of generation of CaC2,kJ/mol |
∆Hdi | = | The heat of melting of the components in calcium carbide,kJ/kg |
Ti | = | The temperature of each reactant,℃ |
Tdi | = | Calcium carbide temperature,℃ |
Q1 | = | The physical sensible heat of the reactant substitution,kJ |
Q2 | = | Heat release from coke combustion,kJ |
Q3 | = | Calcium carbide synthesis absorbs heat,kJ |
Q4 | = | Calcium carbide phase change heat,kJ |
Q5 | = | Generation of heat by substitution,kJ |
Acknowledgements
This work was financially supported by the National Natural Science Foundation of China (NO.22178298 & 51966017), Major Science and Technology Uygur Autonomous Region (NO. 2022A01002-2), and Foundation of State Key Laboratory of Coal Combustion (NO. FSKLCCA2201).
Disclosure statement
No potential conflict of interest was reported by the author(s).
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Notes on contributors
Weihua Liu
Weihua Liu was born in 1999 in Hebei, China. He graduated from Xinjiang University in June 23 with a master's degree in chemical engineering. The research direction is focused on the calculation and optimization of calcium carbide furnace systems.
Bo Wei
Bo Wei received his Ph.D. in engineering from the School of Energy and Power Engineering at Xi'an Jiaotong University and is currently a professor at Xinjiang University. His research areas are mainly focused on combustion and pollution control, slagging and corrosion of combustion equipment and basic theory and application of coal ash chemistry. He has published more than 30 academic papers in journals in the above fields and has chaired several projects.
Tao Yang
Tao Yang is from Jiangxi, China, and he has now received his master's degree in chemical engineering and is pursuing his Ph.D. at Xinjiang University, where his research is focused on the thermodynamics of the calcium carbide reaction.
Jianjiang Wang
Jianjiang Wang received his Doctor of Engineering degree in Chemical Engineering and Technology from Xinjiang University, where he is currently an associate professor.
Maierhaba Abudoureheman
Maierhaba Abudoureheman promovierte am Xinjiang Institute of Physical and Chemical Technology, Chinese Academy of Sciences. She now serves as an associate professor at the School of Chemical Engineering, Xinjiang University.
Jinrong Ma
Jinrong Ma is the legal responsible person of Xinjiang Xinye Energy and Chemical Co., Ltd. and the vice president of Xinye Research Institute, who has rich experience in the application of chemical practical operation.
Jianfei Ma
Jianfei Ma is the Deputy Director of the General Engineering Office of Xinjiang Xinjiang Xinye Energy and Chemical Co., Ltd. and has extensive working experience in the field of practical chemical applications.
Feng Wang
Feng Wang graduated from Xinjiang University and has been working in the chemical and petrochemical field for many years. He is the deputy director of the General Engineering Office of Xinjiang Xinye Energy Chemical Co.
Xian Li
Xian Li, mainly engaged in the research of energy and chemical industry and solid fuel combustion, received his PhD degree from Dalian University of Technology in 2008. From 2008 to 2009, he worked as a postdoctoral fellow at the Max-Planck Institute in Germany, focusing on the catalytic hydrogenation of anthracite coal. From 2009 to 2013, he worked as a COE researcher and an assistant professor at Kyoto U., Japan, with the main research interests in the enhancement and utilization of low-order carbon source materials.