Experimental Investigation And Numerical Simulation On Phosphoric Acid Reactor

The phosphoric acid was the basic raw material in the production of avariety of phosphorus chemical products. It played an important role in thenational economic developed. Phosphoric acid reactor was the core equipmentin the production of phosphoric acid, and the agitator was the key components.The agitator’s performance would directly affect the extraction of phosphaterock slurry filter strength phosphoric acid concentration, the rate ofphosphogypsum washing, mixing power and other important indicators.Therefore, the development of new phosphoric acid mixer would improve theproduction of phosphoric acid.In order to research the phosphoric acid reactor in the flow field slot andimprove mixing reaction efficiency, Fluent6.3was used to stir the flowpattern groove with numerically simulated in this page, and compared theexperimental data by particle image velocimetry(PIV) method. Theoptimization design of the stirrer for phosphoric acid to provide new ideas,and for further experimental study and numerical simulation to lay thefoundation. Main conclusion was as follows:1) When the six inclined leaves agitator and six straight leaf agitator wereworked at the same operating conditions, the flow field of the stirred tankwas simulated by velocity cloud, pressure cloud&the turbulent kineticenergy map, found that the six inclined leaves agitator had better crushing,dispersing properties&a lower power. In the shear less demandingsituation, using six inclined leaves agitator was more reasonable.2) The different stirring speed of flow field distribution, mixing torque&power was considered. The results show that, if only changed the stirringspeed, it did not affect the flow field of a stirred tank, but will increase therate of fluid movement, torque, and mixing power would significantly increased.3) The six inclined leaves agitator axial shunt flow pattern was similar to theaxial flow type. It had much better fragmentation&dispersion properties,and the required power was less than the six straight blades. In the lowshear occasions, using six inclined leaves agitator would be morereasonable.4) MRF model&k-ε model selection was correct because mixing slot flowpattern&velocity distribution was consistent through the PIV experimentand numerical simulation results CFD contrast. PIV experiment methodprovides reference for the numerical simulation，and proofed that the CFDnumerical simulation method to stir the groove flow type had forecasteffect.5) Through simulation tank mixing process of the phosphoric acid reaction,the tank complex flow field, solid concentration distribution&mixingshaft power in the four stirring speed were analyzed. Through thecomprehensive analysis, stirring speed was settled into25RPM, could notonly meet the technological requirements also has a low energyconsumption.CFD numerical simulation method could make guidance forthe optimization design of the agitator.