Capable of producing ultra-pure product water, membrane filtration technologies have a diverse array of applications. Unfortunately, membrane filtration often suffers from membrane fouling and can incur higher energy costs over conventional water treatment processes. Research within the field of membrane filtration focuses on improving filtration performance including water flux, contaminant rejection, and reducing energy requirements. In addition, fouling prevention methods and effective cleaning techniques that do not disrupt or halt filtration are desired. Continued advancement of membrane filtration processes often requires unique approaches, leading to the development and study of novel membrane technologies. The Weavers Research Group studies all filtration processes (i.e., micro/ultrafiltration, forward/reverse osmosis, membrane distillation, etc.). Strategies utilized within this group to improve membrane processes encompass employing novel materials, application of electric fields, ultrasonic methods for defouling/fouling prevention and tactics to reduce energy demands. Figures 1- 4 provide examples of work completed within the Weavers Research Group.
Figure 1. A coupled forward osmosis – membrane distillation processes for recovery of flue gas desulfurization wastewater using waste heat. This process was employed as an energy reducing method to address the complex FGD wastewater produced at coal fired power plants. (Vinny Anderson, 2021).
Figure 2. a) Dead-end style membrane filtration housing containing a novel PZT membrane, b) Cross section view of ultrasonic stimulation and vibration of a PZT membrane during filtration. In this work, a novel piezoelectric PZT membrane was stimulated at an ultrasonic frequency of 72.6 kHz and 100 V to prevent and remove latex particle fouling via the in-situ production of ultrasonic vibrations (John Krinks, 2015). A similar crossflow method has been applied to crossflow filtration of municipal wastewater (Vinny Anderson, 2021).
Figure 3. Crossflow membrane filtration system with integrated ultrasonic probe. Ultrasound was applied to the surface of the membrane for natural organic matter and silica particle defouling/fouling prevention (Dong Chen, 2006).
Figure 4. Cleaning of polystyrene latex particle fouled membranes using externally and internally applied ultrasound (Mikko Lamminen, 2006).