尿素-磷酸铵系复合肥转鼓造粒工艺研究

Study of Drum Granulation Process for Production of Urea-Ammonium Phosphate Compound Fertilizer

对N：P2O5质量比为1：1及N：P2O5：K2O质量比为1：1：l的尿素一磷酸铵系肥料进行生产对比试验，并对造粒物料温度、粒度组成、氨气损失及pH等相关因素进行统计分析。试验结果表明：尿素-磷酸铵系三元肥料在造粒温度为70℃左右、pH控制在5．5～5．8、返料比为1．3—1．5的条件下，可维持造粒系统的粒度平衡；造粒机平均装载系数为20％，物料停留时间为4～7min，此时造粒过程的成粒率可维持在较高水平，粒化物料水分含量合适，氨损失低，全系统能稳定运行。

Comparative test of urea-ammonium phosphate compound fertilizer production is carried out, the mass proportion of N： P2O5 is 1 ： 1 and mass proportion of N： P2O5 ： K2O is 1 ： 1 ： 1, statistical analysis is made of related factors, such as granulation temperature, particle size distribution, ammonia loss rate and pH. Test results show that for the urea-ammonium phosphate ternary system, under conditions that granulation temperature is about 70℃, pH is controlled between 5.5 to 5.8, and recycle ratio is 1.3 to 1.5, the granularity balance of the granulation system can be maintained ; the average loading coefficient of the granulator is 20%, and material residence time is 4 - 7 minutes, under the conditions, granulation rate is in higher level, the moisture content of granulation materials is appropriate, ammonia loss is low, and the operation of total system is stable.