Research And Comparison Of Micro-reactor And Traditional Reactor On Phosphoric Acid Decomposition Of Phosphate Rock

Phosphoric acid decomposition of phosphate ore to produce phosphoric acid is one of the most basic methods in the production of wet phosphoric acid.This paper uses a micro-reactor to produce two-step wet phosphoric acid.The first step uses phosphoric acid to decompose phosphate ore,that is,phosphate ore and phosphoric acid are pre-decomposed under the action of different reactors.The second step is to add concentrated H₂SO₄and Ca（H₂PO₄）₂ to form a precipitate of calcium sulfate and phosphoric acid insoluble in the liquid phase.The traditional reactor process for phosphoric acid decomposition of phosphate ore has the problems of long reaction time and high liquid-solid ratio.The liquid-solid ratio of the traditional reactor process is 9:1,the amount of phosphoric acid is relatively large,the reaction time is 3h,the reaction time is too long,the production efficiency is low,and the production cost is increased.This topic using500 type umt microchannel reactor,using the single factor experiment method,the temperature,reaction time,liquid-solid ratio and the concentration of phosphoric acid and phosphate rock grain size influence on the decomposition rate of phosphate rock,and through many experiments,the orthogonal experiment of microreactor technology,it is concluded that the best experimental conditions,and then compared with the traditional reactor technology,At the same time,the ultrasonic reactor and the high shear reactor processes were studied and compared with the micro-reactor processes.The whiteness of phosphogypsum under the microreactor process was measured by WSB-X whiteness tester,and then compared with that under the traditional reactor process,the whiteness of phosphogypsum under the traditional reactor process was between 85-88.The experimental results show that the optimal reaction conditions for phosphoric acid decomposition of phosphate ore in the microreactor process are as follows:The temperature is 70°C,the ratio of liquid to solid is 8:1,the reaction time is30min,the concentration of phosphoric acid is 30%,and the particle size of phosphate rock is 180 mesh.Under the above conditions,the decomposition rate of phosphate rock is 98.6%.By orthogonal test,the optimal decomposition rate of phosphate rock in ultrasonic reactor and high shear reactor is 93.9%and 95.8%,respectively.Under the microreactor process,the whiteness of phosphogypsum can reach 92.Compared with the traditional reactor process,the microreactor process reduces the liquid-solid ratio,shortening the reaction time,and increasing the whiteness of phosphogypsum.