Numerical modeling and control of solids separation using continuously moving fine mesh filters. (23rd February 2019)

• Record Type: Journal Article
• Authors: Sherratt, Anthony; DeGroot, Christopher T.; Straatman, Anthony G.; Santoro, Domenico
• Is Part Of: Chemical engineering science. Volume 195(2019)
• Page Start: 881
• Page End: 893
• Publication Date: 2019-02-23
• Subjects: Filtration -- Primary wastewater treatment -- Solids separation -- Control; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2018.10.033
• Languages: English
• ISSNs: 0009-2509

Abstract

Graphical abstract: Highlights: Cake resistance can be measured by drainage column with continuous level monitoring. Cake resistance can be scaled based on suspended solids in influent sample. A PID controller can maintain water level when suspended solids concentration varies. A one-dimensional process model can accurately predict filter performance. Abstract: This work presents a numerical model for solids separation using continuously moving, inclined fine mesh filters. One of the main difficulties in modeling fine mesh filters is the characterization of the cake resistance as the solids accumulate on the filter. It is proposed to model the cake resistance using a gravity drainage column experiment implementing continuous water level monitoring. Based on the drainage curve, an analytical formulation is developed for the cake resistance, as a function of the filtered volume per unit area, V . The removal efficiency is also correlated with V through a sieve test. With the cake resistance and removal efficiency functions determined, a one-dimensional filter model is developed. Since the total suspended solids concentration varies as a function of time, and will not always be the same as that tested, a technique of scaling the cake resistance is introduced. A PID control algorithm is also developed into the model, so that the filter rotation speed can be controlled to maintain a set water level upstream of the filter. Results for sizing curves are given, as well as results for the PID controller operation, and validation results based on full-scale pilot testing.