磷石膏-废氨水固定CO_2的试验研究

Experimental study on carbon dioxide sequestration by phosphogypsum and waste aqueous ammonia

利用企业废氨水、磷石膏与CO_2制备硫酸铵和碳酸钙,可以实现磷石膏和废氨水的资源化利用。系统考察了反应温度、反应时间、液固比、氮硫比、CO_2流量、搅拌速度和水洗预处理对硫酸钙转化率的影响。结果表明:在反应温度40℃、反应时间60min、液固比8.0、氮硫比2.4、CO_2流量500mL/min、搅拌速度300r/min、水洗预处理3次的最佳反应条件下,硫酸钙的转化率可达到96.11%。试验结果对磷石膏固废的综合利用和CO_2减排具有一定的实际意义。

The production of ammonium sulfate and calcium carbonate by reaction of waste aqueous ammonia, phosphogyp- sum and COz can realize the resource utilization of phosphogyp- sum and waste aqueous ammonia. The influences of reaction temperature, time of reaction, liquid-solid ratio, nitrogen-sulfur ratio, CO2 flowrate and stirring speed, water pretreatment on calcium sulfate conversion rate are investigated in the system. The re suits showed that the conversion rate of calcium sulfate could reach 96.11% under the optimum conditions of temperature 40 ℃ ,time of reaction 60 min, liquid-solid ratio 8. 0, nitrogen-sulfur ratio 2.4 and nitrogen-sulfur ratio 2.25, CO2 flowrate 500 mL/ rain, stirring speed 300 r/min and water pretreatment 3 times. The experimental results are of practical significance for the corn prehensive utilization of phosphogypsum solid waste and CO2 e mission reduction.