A Systematic Approach to Understand and Optimize Solids Dewatering Process

Solids handling process is an essential element of all wastewater treatment plants (WWTP). In many plants, it may account for 50% of the plant's operating budget. Dewatering process plays an important role in sludge volume reduction which in turn will result in lower solids processing and handling costs. A systematic method was proposed in this paper to investigate the factors impacting the sludge dewatering process and to optimize the dewatering operation. This systematic approach involved both bench-scale tests and full-scale experiments. The bench-scale tests intended to identify the best polymer type and dosage for a specific sludge and also explore other impacting factors like the holding time of dewatering process feed sludge. A series of full-scale experiments were used to determine the best dewatering process operating parameters. Based on the results of these two sets of tests, a dewatering process control guideline could be developed for providing operators a practical process control range in order to achieve the best operational efficiency.