利用电石渣进行赤泥脱碱研究  

Dealkalization of Red Mud with Calcium Carbide Slag

作　　者：王亚丽[1] 丁思哲 王玲玉 WANG Yali;DING Sizhe;WANG Lingyu(Faculty of Materials and Manufacturing,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学材料与制造学部,北京100124

出　　处：《硅酸盐通报》2023年第10期3617-3623,共7页Bulletin of the Chinese Ceramic Society

基　　金：北京科技计划项目(Z221100007522002)。

摘　　要：赤泥是制铝工业提取氧化铝时排出的工业固体废弃物,高碱含量限制了其利用。利用电石渣替代天然钙基材料进行赤泥脱碱,分析脱碱温度、电石渣掺量、液固比、反应时间四个因素对脱碱效果的影响,探究电石渣进行赤泥脱碱的反应机理。结果表明,随着温度升高、电石渣掺量增加、反应时间增加,赤泥脱碱效率升高;在温度为90℃、液固比为4∶1、反应时间为360 min、赤泥与电石渣的质量比为1∶1的反应条件下,脱碱效率达到81%,脱碱后赤泥中的Na2O含量不大于1%(质量分数),满足水泥原料的要求。电石渣进行赤泥脱碱反应符合内扩散未反应收缩核模型,提高反应温度与反应物的质量均可提高脱碱率。Red mud is an industrial solid waste discharged during the extraction of aluminum oxide in the aluminum industry.Its high alkali content limits its utilization.Using calcium carbide slag to replace natural calcium-based materials for red mud dealkalization,the effect of four factors including dealkalization’s temperature,carbide slag’s dosage,liquid-solid ratio and reaction time on red mud dealkalization were analyzed,and the reaction mechanism of calcium carbide slag for red mud dealkalization was explored.The results show that as the temperature increases,the amount of calcium carbide slag increases,the reaction time increases and the dealkalization efficiency increases.Under the reaction condition of temperature 90℃,liquid-solid ratio 4∶1,reaction time 6 h and a 1∶1 mass ratio of red mud to calcium carbide slag,the dealkalization efficiency reaches 81%.After dealkalization,the Na2O content in the red mud is not more than 1%(mass fraction),which meets the standard for use as cement raw material.For red mud dealkalization reaction by calcium carbide slag conforms to the internal diffusion unreacted shrinking core model,and increasing the reaction temperature or the amount of reactants can improve the dealkalization rate.

关 键 词：赤泥 石灰脱碱 电石渣 脱碱效率 内扩散未反应收缩核模型 

分 类 号：TU528[建筑科学—建筑技术科学]