菱镁矿煅烧制备高活性MgO工艺

主要对高活性MgO及镁基水泥的制备工艺进行研究。利用小库容回转炉煅烧菱镁矿制备轻烧MgO,通过柠檬酸显色法和修正水化法测定菱镁矿在不同条件下煅烧产物的活性,分析煅烧过程中煅烧温度、保温时间、升温速率等因素对煅烧产物活性的影响。再以煅烧产物轻烧MgO作为基本原料之一配制镁基水泥并制备水泥试块,探究镁基水泥的强度特性以及不同养护方式对其产生的影响。结果表明镁基水泥在标准养护条件下强度较低,但碳化养护可以很大程度提高镁基水泥的强度,达到普通硅酸盐水泥的强度水平。同时根据水泥试块在碳化养护过程中的增重情况,分析使用含高活性MgO的镁基水泥作为CO2捕集与封存材料的可行性。

Study on the process of the Preparation of Activated MgO by Calcining Magnesite

The research on the preparation of activated MgO and Mg-based cement was carried on in this paper.The magnesite of the little storage capacity rotary furnace was adopted to prepare light-burnt MgO.The activation of calcinate under different condition was determined by the citric acid coloration method and the correction hydration method and the influence of calcination temperature,holding time and heating rate on the activation of calcinate was analyzed.Then the light-burnt MgO was used as one of the basic raw materials to prepare Mg-based cement and cement block.Meanwhile,the influence of strength properties of Mg-based cement and different curing methods were studied.The results showed that the strength of the Mg-based cement was relatively low in the standard curing condition,but the carbonated curing can greatly improve the level of Mg-based cement strength,reaching the level of the ordinary portland cement.At the same time,according the weight gain of the cement block during the course of carbonated curing,the feasibility of using high activity of MgO as CO2 capture and sealing materials was analyzed.