ABSTRACT
Phosphoric acid plant products have quality problems where the most quality deviations are caused by the quality of phosphogypsum not meeting the standards. This results in the high cost of gypsum management and great loss due to the waste or unusable products, thus, the plan–do–check–act (PDCA) method is used in search of a solution. The solution that has been successfully carried out is, firstly, by modifying the phosphogypsum washing system, specifically on its filter by substituting low pH water to a higher pH for washing, which generally functions to dissolve the water-soluble P2O5 on phosphogypsum. The second solution is by adding a distribution box to the hydration section, which functions to circulate some of the slurries to lengthen the slurry residence time in hydration so that the pH of phosphogypsum is better. This innovation is effective in reducing the low pH deviation of phosphogypsum products so that the potential of phosphogypsum can be maximized in the future while following government regulations.
