CO2 mineralization of carbide slag for the production of light calcium carbonates

• 作者: Tongyang Zhang Guanrun Chu Junlin Lyu Yongda Cao Wentao Xu Kui Ma Lei Song Hairong Yue Bin Liang
• 来源期刊: 中国化学工程学报（英文版）
• 年，卷（期）: 2022,（3）
• 页码范围: 86-98
• 页数: 13页
• 语种: 英文

摘要

The production of polyvinyl chloride by calcium carbide method is a typical chemical process with high coal consumption,leading to massive flue gas and carbide slag emissions.Currently,the carbide slag with high CaO content is usually stacked in residue field,easily draining away with the rain and corroding the soil.In this work,we coupled the treatment of flue gas and carbide slag to propose a facile CO2 mineral-ization route to prepare light calcium carbonate.And the route feasibility was comprehensively evaluated via experiments and simulation.Through experimental investigation,the Ca2+leaching and mineraliza-tion reaction parameters were determined.Based on the experiment,a process was built and optimized through Aspen Plus,and the energy was integrated to obtain the overall process energy and material con-sumption.Finally,the net CO2 emission reduction rate of the entire process through the life-cycle assess-ment method was analyzed.Moreover,the relationship between the parameters and the CO2 emission life-cycle assessment was established.The final optimization results showed that the mineralization pro-cess required 1154.69 kW.h.(t CO2)-1 of energy(including heat energy of 979.32 kW·h·(t CO2)-1 and elec-trical energy of 175.37 KW·h·(t CO2)-1),and the net CO2 emission reduction rate was 35.8％.The light CaCO3 product can be sold as a high value-added product.According to preliminary economic analysis,the profit of mineralizing can reach more than 2,100 CNY.(t CO2)-1.