(129c) Enhancing Filtration Rate of Phosphoric Acid by Polymers Application

Phosphoric acid is primarily produced by what is known in the industry as the "wet process", the phosphate rock is fed into an attack tank or reactor and reacted (digested) with sulfuric acid (H2SO4). this reaction led  to the production of phosphoric acid (H3PO4) and calcium sulfate dihydrate or gypsum(CaSO4·2H2O). Filtration is a key operation in the manufacturing process of phosphoric acid, the objective of this operation is to separate the phosphogypsum and phosphoric acid. My presentation will be subdevised on two main part, in the first part i will discuss the parameters that affect the filtration operation for the separation of phosphoric acid from phosphogypsum cake. In the second part, I  will present a result of study for the filtration rate improvement and the reduction of P2O5 losses in the gypsum cake by using a suitable flocculant. The results of this study  is based on the online mesurement of filtration rate and soluble content of P2O5 in gypsum cake, using bench scale of filtration unit.  the study have been conducted in the case of two different process for phosphoric acid production  Rhone Poulenc and Pryon.