碳酸钙渣悬浮态煅烧试验

Study on suspension calcination technology of calcium carbonate residue

碳酸钙渣是利用磷石膏制备硫酸铵的新型化工副产品,通过煅烧可以得到高活性石灰。本文利用西安建筑科技大学粉体研究所自行研制的小型模拟悬浮态煅烧试验装置和马弗炉堆积态煅烧装置,对碳酸钙渣快速煅烧工艺进行了小型实验室试验,并探讨了两种煅烧方式对活性的影响,提出了产品检测方法,对比了堆积态和悬浮态煅烧产品的分解率和活性等物化性能指标。结果表明:相对堆积态煅烧,悬浮态煅烧时CaCO3的表观分解率可以达到99%以上,而且得到的产品有较大的比表面积和较多的空隙,表现出较高的活性;悬浮态煅烧的热效率优于传统的堆积态煅烧装置,可用于大规模工业化生产。

The calcium carbonate residue is a new chemical byproduct in the production of ammonium sulfate using phosphogypsum. Lime with high reactivity can be obtained by the process of calcium carbonate calcination. A pilot experimentation on calcium carbonate calcination was presented in this paper. The calcining devices were developed by the Powder Institute of Xi＇An University of Architecture and Technology. The impacts of different calcination methods on lime were discussed. In addition, the product detection methods were suggested. The decomposition rates and activity indicators in accumulation state and suspension state were compared. The results showed that suspension calcining process had better composition rate compared to the accumulation calcination. The CaCO3 apparent decomposition rate can reach 〉99% and the product obtained had larger specific surface area, better porosity, and higher activity. In addition, the heat efficiency of suspension calcination was better than traditional calcination processes. Therefore, the suspension calcination process can be potentially used for large-scale industrial production.