硫酸氢钾反应嫁接AZF工艺生产硫基复合肥中试研究

Pilot Plant Study of S-based Compound Fertilizer Production with Potassium Bisulfate Reaction on AZF Process

为降低AZF工艺生产复合肥的生产成本,采用氯化钾来代替硫酸钾生产硫基复合肥,对硫酸氢钾反应嫁接AZF工艺进行了中试规模的试验,验证低水含量的混酸料浆输送、管式反应器氨化以及氨化后料浆黏结成粒的性能,同时对该工艺嫁接后的水热平衡进行了分析。试验结果表明,硫酸氢钾与中浓度磷酸混合后的混酸水含量一般为28%,温度一般为90～100℃;造粒过程中管式反应器的氮磷比一般为0.22或0.47;嫁接后工艺的液固比为0.285左右,经干燥机分流20%～40%的液相量后,造粒机内的液固比可以降至较佳造粒液固比。对生产装置进行水平衡与热平衡分析表明,经嫁接技改后的AZF工艺产能不降低,造粒性能良好,无需增加热风炉干燥能力,但需新增干燥机管式反应器。原装置经技改后能达到用氯化钾生产合格硫基复合肥的效果,降低生产成本。

To reduce the production cost of compound fertilizer with AZF process,potassium chloride is used in lieu of potassium sulphate to produce S-based compound fertilizers.Pilot plant scale study is done for potassium bisulfate reaction on AZF process,to test the performance of transfer of mixed acid slurry with low water content,ammoniation of tubular reactor and granulation performance of slurry sticking after ammoniation.Water and heat balance of the process transplantation is analyzed.The study results show,after mixing of potassium bisulfate,the water content in the mixed acids is typically 28%,temperature is 90～100 ℃;during granulation,the N/P ratio in the tubular reactor is normally 0.22 or 0.47;after transplantation,the liquid/solid ratio is about 0.285.After 20%~40% liquid phase is split through the dryer,the liquid/solid ratio in the granulator can be reduced to the optimum liquid/solid ratio.Analysis of water balance and heat balance of the production facility shows that the production capacity of the AZF after revamp is not decreased,the granule performance is good,there is no need to add drying capacity of the heating furnace,but the fryer tubular reactor need to be added.After revamp,the existing unit can achieve the effect of producing qualified S-based compound fertilizer using potassium chloride,and reduce the production cost.