Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, 650500, Yunnan, China.
National-Regional Engineering Center for Recovery of Waste Gases From Metallurgical and Chemical Industries, Kunming, 650500, Yunnan, China.
Environ Sci Pollut Res Int. 2022 Dec;29(59):88519-88530. doi: 10.1007/s11356-022-21894-4. Epub 2022 Jul 14.
In order to give full play to the alkaline neutralization value of carbide slag and reduce the environmental hazards of carbide slag, it is of great practical significance to study the resource utilization of carbide slag. The adsorption of sulfur compounds on carbide slag was studied in the laboratory, and the process parameters of carbide slag desulfurization were explored and optimized. The specific surface area, pore distribution, and other physicochemical parameters were analyzed by XRD and SEM, which explained the changes of products and carbide slag before and after desulfurization. The test results show that carbide slag and limestone have almost the same desulfurization effect. The kinetics of carbide slag desulfurization process conforms to pseudo-first-order kinetics, and the sulfur content of calcium carbide slag reaches to 1000 mgSO·g. A project demonstration was carried out in the gold smelting Tielu Plant of Zhenyuan Huashuo Precious Metals Development Co., Ltd., in Yunnan. The results of the 2-year demonstration project showed that the desulphurization efficiency of the four-stage series desulphurization tower exceeds 95%. The concentration of sulfur dioxide in the discharged flue gas is reduced to less than 20 mg·m, which meets the requirements of ultra-low emission standard in China. Therefore, whether from theoretical research or engineering practice analysis, it is feasible to replace limestone with calcium carbide slag for flue gas desulfurization. The paper also discusses the problems existing in the demonstration project, and provides a new idea of "using waste to treat waste" in order to solve the problem of carbide slag disposal.
为了充分发挥电石渣的堿性中和值，降低电石渣的环境危害，研究电石渣的资源化利用具有重要的现实意义。本研究在实验室条件下对电石渣吸附硫化物的性能进行了研究，探索并优化了电石渣脱硫的工艺参数。采用 XRD 和 SEM 对电石渣脱硫前后的比表面积、孔径分布等物化参数进行了分析，解释了产品和电石渣脱硫前后的变化。试验结果表明，电石渣和石灰石脱硫效果几乎相同。电石渣脱硫过程动力学符合准一级动力学，电石渣中硫含量达到 1000mgSO·g。在云南镇沅华烁贵金属开发有限公司铁炉金冶炼厂进行了工程示范，2 年的示范工程结果表明，四塔串联脱硫塔的脱硫效率超过 95%。排放烟气中二氧化硫的浓度降低到 20mg·m 以下，达到了中国的超低排放标准。因此，无论从理论研究还是工程实践分析，用电石渣代替石灰石进行烟气脱硫都是可行的。本文还探讨了示范工程中存在的问题，并提出了“以废治废”的新思路，以解决电石渣的处置问题。
