Diammonium phosphate produced with a high-pressure pipe reactor

摘要

Improved, simple, energy-efficient, and easy-to-operate process for producing granular diammonium phosphate (DAP) fertilizers from anhydrous ammonia, phosphoric acid, sulfuric acid, and water utilizing a rotating drum granulator and a pipe reactor in combination with a specially designed slurry distributor. The pipe reactor operates at pressures of more than 80 pounds per square inch gage and utilizes a special low- impact distributor to uniformly distribute a wide-angle spray of slurry onto the bed of recycled solids in the drum granulator and to provide for a minimum of bed disruption and deformation. This energy-efficient process produces dry, free-flowing granular DAP with little or no fossil- fuel heating requirements for drying and with low recycle ratios which allow for high production rates or increases in production rates when the process is retrofitted into existing plants. Because less equipment is required and because of process efficiencies, both capital and operating costs are decreased either for a new plant or a retrofit to an existing plant as compared to plants producing DAP with the conventional tank preneutralizer process.