Abstract:

At present, CO₂ capture and storage technology is the most effective way to achieve CO₂ emission reduction. Wherein, CO₂ mineral sequestration mainly utilizes the reactions of carbon dioxide with calcium and magnesium silicate minerals to form stable carbonates, and thus can permanently store CO₂. The principles and pathways for CO₂ mineral carbonation are briefly introduced in this paper. Indirect carbonation receives more attentions due to the moderate reaction condition, higher mineralization efficiency and possibility for recovering valuable byproducts. This paper reviews and compares the carbonation process by using natural minerals and industrial solid wastes as feedstock. It is found that the latter is more conducive to the CO₂ mineralization process. This process realizes the disposal of industrial solid wastes while storing CO₂, realizing the treatment of waste with waste, which had certain advantages in economy. Based on above, this paper takes blast furnace slag as representative and summarized its research progress in CO₂ mineral carbonation. It is pointed out that using recyclable reagents and recovering valuable elements from blast furnace slag can improve the economy of CO₂ mineralization. To realize the industrial application of the CO₂ mineralization technology, the scale-up experiments, life cycle assessment and developments of new approaches with low energy consumption should be paid more attentions to.

Key words: CO₂ mineralization, industrial solid wastes, carbonation, ammonium sulfate, blast furnace slag

摘要：

CO₂捕集与封存技术是目前实现碳减排最有效的方法。其中，CO₂矿物封存（又称CO₂矿化）是利用CO₂与含钙镁硅酸盐矿物进行反应使CO₂以稳定的碳酸盐形式永久储存起来。本文首先介绍了CO₂矿化的基本原理和技术路线，其中间接矿化反应条件较温和、矿化效率更高、得到的产物也更纯，因此对于CO₂间接矿化的研究也更广泛。本文综述并对比了天然矿物及工业固废矿化CO₂的研究进展，指出工业固废更有利于CO₂矿化过程。工业固废矿化CO₂过程矿化CO₂的同时处理了工业固废，实现以废治废，因此它在经济上也是具有一定优势。在此基础上，本文以高炉渣为代表，介绍了其矿化CO₂的详细研究进展，指出采用可循环的助剂、回收高炉渣中有价元素可提升矿化过程经济性。对于CO₂矿化过程的放大试验、生命周期的评估及低能耗的新工艺开发将是CO₂矿物封存实现工业化的关键。

关键词: CO₂矿物封存, 工业固废, 碳酸化, 硫酸铵, 高炉渣