电石渣在燃煤电厂脱硫工艺中的应用研究进展

近年来，电石渣在燃煤电厂干法脱硫工艺的应用中取得了较多进展，但在湿法脱硫的应用中仍存在消溶特性差、亚硫酸钙氧化率低、石膏脱水困难等诸多问题，导致其难以大规模推广。本文从电石渣的理化性质出发，分析了孔隙结构、反应温度、Ca/S摩尔比对脱硫效率的影响，并探讨了电石渣作为脱硫剂对循环流化床锅炉效率及运行的影响，结合电石渣的消溶特性、浆液氧化特性及石膏脱水特性，分析了电石渣在湿法脱硫工艺应用中存在的问题，提出了一种以电石渣为原料，利用燃煤机组再生水深度处理系统生产石灰石浆液的工艺路线，并在2×660MW超超临界燃煤机组再生水深度处理系统中进行了可行性试验，当Ca(OH)₂纯度≥95%时，合理的污泥掺配比例区间为50%~70%，所产石膏达到了二级石膏的品质要求。

Progress in application of calcium carbide slag in desulfurization process of coal-fired power plant

Calcium carbide slag has made more progress in the application of coal-fired power plant drydesulfurization process in recent years. However, there are still many problems in the application of wet desulfurization, such as poor dissolving characteristics, low oxidation rate of calcium sulfite, difficult dehydration of gypsum and so on. Based on the physical and chemical properties of calcium carbide slag, the effects of pore structure, reaction temperature and Ca/S ratio on desulfurization efficiency and the effect of the introduction of calcium carbide slag on the efficiency and operation of circulating fluidized bed boiler were both analyzed. In terms of ablation characteristics, slurry oxidation characteristics and gypsum dehydration characteristics of calcium carbide slag, the problems in the application of calcium carbide slag in wet desulfurization process were analyzed, and a new process route for producing limestone slurry taking advantage of reclaimed water advanced treatment system using calcium carbide slag is proposed. A feasibility test was conducted in the reclaimed water advanced treatment system of a 2×660MW ultra-supercritical coal-fired unit. When the purity of calcium hydroxide is ≥95%, the reasonable sludge blending ratio range is 50%—70%, and the produced gypsum meets the quality requirements of secondary gypsum.