Reduction of Sludge in a Zinc Phosphating Process - A DOE Study 970730
With ever-increasing emphasis on the environment and the decrease in available landfill locations, the generation and disposal of phosphate sludge has become a challenge in many countries. This study examines key parameters of a trication zinc phosphating process and their effect on sludge generation. Using Design Of Experiment, (DOE), principles, the effects and interactions of the key parameters were identified and used to optimize the process to achieve a 30% reduction in sludge without compromising performance. Included in the results are the derived regression equations for sludge, coating weight, metal loss, p-ratio and APGE cosmetic corrosion.