Session: 17-01-01: Research Posters

Paper Number: 150513

150513 - Modeling of Microplastic Removal From Municipal Wastewater With Ceramic Membranes 

The main way that microplastics (MPs) and nanoplastics (NPs) get into the aquatic environment is through municipal wastewater effluent. Membrane bioreactor (MBR) systems are emerging for treating municipal wastewater among various wastewater treatment equipment and facilities. Most traditional membrane procedures employ polymeric membranes, which suffer from membrane fouling and may become damaged or abrasive, leading to the generation of more MPs and NPs. We propose that MPs and NPs can be eliminated while avoiding the problems associated with existing polymeric membrane methods by utilizing a membrane bioreactor that incorporates microfiltration (MF) or ultrafiltration (UF) employing ceramic membranes into the wastewater treatment process. 
The main issue, though, is that little is understood about the fouling behavior and MP/NP removal efficiency and underlying mechanisms in membrane processes, especially for ceramic membranes. Using computational fluid dynamics (CFD), we will assess the removal of MPs from municipal wastewater in anaerobic and aerobic membrane bioreactors. Two physical models of anaerobic/aerobic ceramic membrane units were built with MFiX, an open-source multiphase computational fluid dynamics software package developed by the National Energy Technology Laboratory, the US Department of Energy. This poster will elaborate on how an anaerobic/aerobic ceramic membrane bioreactor (AnCMBR/ACMBR) removes MPs effectively and the mechanism of membrane fouling through quantitative data on the hydrodynamic performance of CFD. A pilot-scaled flat-sheet ceramic membrane was considered for AnCMBR and a tubular ceramic membrane was used for ACMBR. The physical model of the tubular ceramic UF membrane module was constructed, considering steady, isothermal, and incompressible flow. In the modeling, two-phase mass and momentum conservation equations were solved, aiming to provide a reliable basis for improving ceramic membrane bioreactor design and operation, and enhancing municipal wastewater treatment efficiency.
The creation of particle bridges is essential to the structure of the membrane fouling cake and the overall filtration efficiency in the filtering process when the pores are bigger than the particle size. We employed the two-way coupling of CFD–discrete element method (DEM) to model the deposition properties of particles in the pores of ceramic membranes in order to comprehend the microscopic information needed for the bridging mechanism. The membrane fouling mechanism was revealed at the level of the continuum fluid model by dynamically studying the deposition morphology and particle bridging process. We looked at how the inflow velocity and particle concentration affected the process of building the bridge. The findings demonstrate that the transition stage and the clean filtering stage are traversed by the bridging function of particles. The creation of particle bridges and the effectiveness of filtration are significantly influenced by particle concentration and inlet flow rate.
Keywords: municipal wastewater, microplastics, ceramic membrane, microfiltration, ultrafiltration
 

Presenting Author: Elisha Sam Acquah Tarleton State University

Presenting Author Biography: My name is Elisha Sam Acquah. I hold a Bachelor of Science degree in mechanical engineering from Kwame Nkrumah University of Science and Technology, Ghana. I am currently pursuing my master’s in mechanical engineering at Tarleton State University in Stephenville, Texas. I am working as a research assistant under Dr. Hongdu Du's supervision. I am working on simulations to understand the fouling behavior, microplastics (MP) and nanoplastics (NP) removal efficiency, and underlying mechanisms in membrane filtration processes, especially for ceramic membranes, through computation fluid dynamics (CFD). And also demonstrate how the cake layer forms during the removal of MP and NP ceramic membrane filtration, causing fouling, and how to optimize to reduce fouling.

Authors:

Elisha Sam Acquah Tarleton State University
Hongbo Du Tarleton State University