Retrofitting of a Full-Scale Dewatering Operation for Industrial Polymer Effluent Sludge

Abstract

This paper presents a comprehensive study on the redesign of a dewatering process in a polymer sludge wastewater treatment plant. The study focuses on addressing the challenges posed by high levels of organic pollutants in the sludge, with the aim of enhancing dewaterability, reducing odors, and minimizing suspended solids. Initially, a vacuum belt filter was utilized, but it proved inadequate in removing sufficient water, resulting in substantial annual disposal costs. To address this issue, a filter press system was proposed, which significantly improved the dewatering process, producing a dryer cake with a solid content of 35%, compared to 19% achieved by the vacuum belt filter. Performance evaluation of the processes was conducted based on concentration of solids and capture efficiency, demonstrating the superiority of the filter press method. Furthermore, the filtrate obtained through the filter press met local discharge regulations, eliminating the need for additional treatment before disposal. The implementation of the filter press not only improved the dewatering process and ensured compliance with discharge standards but also resulted in substantial cost savings of up to 50% per year. The payback period for the current system was determined to be 1.5 years, highlighting the economic advantages of the filter press. Overall, the findings of this study emphasize the practical advantages of the filter press in handling sludge cakes and filtrate for disposal, making it a favorable choice for dewatering polymer sludge and other wastewater treatment plants.