Published: April 9, 2021 By

Wastewater reuse is a growing application in many areas of the world as water scarcity is becoming a major issue due to climate change and exponential population growth. In Colorado, water reuse is becoming more viable because of drought and increased water demand. However, chemical contamination from industrial and domestic waste are a main concern of direct potable reuse project because of their ability to pass through conventional water treatment processes. Chemicals contaminants are well known to harm aquatic wildlife and can cause chronic illness if ingested at high concentrations. Membrane filtration can be applied in these settings to physically separate larger contaminants, but membrane fouling can reduce water quality and membrane lifetime. Advanced Oxidation Processes (AOPs) and ceramic membrane filtration can work together in water treatment processes to enhance chemical removal. This study investigated the synergistic effects of ceramic microfiltration and ozonation compared with other AOPs in secondary wastewater effluent. Ozone enabled oxidation of micropollutants, anthropogenic trace organic contaminants, were studied by measuring total organic carbon (TOC) and ultraviolet absorption (UVA254) reduction. Ozonation with ceramic microfiltration was compared to other AOPs such as UV with hydrogen peroxide (UV/H2O2) which can remove chemicals, pathogens, and bio foulants forming on the membrane surface. These bio foulants physically block membrane pores and lead to an increased transmembrane pressure (TMP) needed to push water through the membrane, as well as irreversible membrane fouling. Less membrane fouling leads to less frequent backwashing and chemical cleaning of the membranes, thus lowering operating costs and extending the lifetime of the membranes for water utilities. The study found that ozonation coupled with ceramic microfiltration was the most efficient in reducing TOC (~35-40%) and UVA254 (~60-70%). Overall, advancing technologies in wastewater reuse shows that potable reuse is becoming more viable and can enhance water availability while protecting natural water quality.