Understanding and Operating Pretreatment Systems

As demand for high and ultra pure water increases, enhanced performance from pretreatment systems become more and more necessary. When operated at full potential, pretreatment systems can greatly improve downstream unit processes, however many pretreatment systems become a mysterious “black box” that are often neglected. Proper training and understanding of the intricacies of pretreatment variables and constraints is a valuable resource for any system operator. This paper discusses the application of true solids contact clarification and multi-media filtration in lime softening and turbidity reduction applications. Basic mechanical and process features as well as testing, instrumentation and control parameters will be covered. Terminology and analysis techniques for optimization will be introduced. The objective of this paper is to give the plant operator the understanding necessary to optimize the effluent quality and operability of the solids contact clarifier and multi-media filter pretreatment system.