高温烧结磷石膏钙渣制备轻质碳酸钙

Preparation of Light Calcium Carbonate from Phosphogypsum Calcium Slag by High-temperature Sintering

以磷石膏钙渣为原料,通过高温煅烧,然后经消化、精制、碳化,制成轻质碳酸钙产品。研究结果表明:高温煅烧的最佳温度为1000℃,最佳煅烧时间为1.0 h;沉淀反应的初始反应温度为60℃,Ca(OH)_2乳液质量浓度为70 g/L,CO_2流量为1.8 L/h。制备的轻质碳酸钙产品各项指标均达到HG/T2226—2000《工业沉淀碳酸钙》标准的要求。其中,沉降体积远优于行业标准,达到了4.0 mL/g。

Light calcium carbonate was prepared using phosphogypsum calcium slag as raw material via high temperature sintering, digestion and carbonization. The optimum conditions are as follows： sintering temperature 1 000℃, sintering time 1.0 h, initial precipitation temperature 60℃, mass concentration of Ca （OH）2 emulsion 70 g/L, and CO2 flow 1. 8 L/h. All quality indexes of the product can meet the standards of HG/T2226 - 2000, and among them, the sedimentation volume can reach 4.0 mL/g, which is most better than the trade standard.