Q. We are about to specify a new powder coating plant. We would like to investigate alternative methods of cleaning and pretreatment. We currently use a four-stage iron phosphate system which requires the waste water to go through effluent treatment before dispatching to the drain. Do you have any ideas? P.S.
A. My first question to you would be how satisfied are you with your current pretreatment process? If you have a positive history with the current pretreatment chemical process and supplier, you may want to consider remaining with that combination. Qualification of a new supplier of a similar pretreatment system is not an insignificant undertaking, generally requiring several preliminary trials and scale-up prior to a production line trial. What you are considering is transforming, in all likelihood, both the supplier and the pretreatment process and chemistry. This undertaking would require a significantly larger validation plan and trials.
If you have a successful history with your current pretreatment process and supplier, you may instead want to consider an alternative effluent treatment process. Have you considered several alternative treatments such as evaporators (essentially distillation units), ion exchange and reverse osmosis to manage this waste stream? You could benefit from focusing your efforts on your core business rather than on the waste-treatment process.