Application of Electrochemical Processes in Onsite Wastewater Systems: Electrocoagulation and Hypochlorite Production
Ineffective treatment of decentralized wastewater by septic systems contribute to both the spread of pathogens and increased nutrient loading in ground and surface waters. These nutrients and pathogens create economic, ecological, and public health consequences for society at large. This thesis is comprised of two studies investigating the applicability of electrochemical technologies to these problems. In the first study, a continuous manifold electrocoagulation system was used to treat representative synthetic onsite wastewater with the goal of removing nutrients. Maximally, more than 95% reduction in orthophosphates and 20% reduction in ammonia was observed at a current density of 2.8 mA/cm2, however, reduction in chemical oxygen demand was not observed. The second study was a bench scale analysis of an electrochemical cell to produce hypochlorite disinfectant tested at several operational parameters. It was found that the greatest disinfectant yields were achieved using an aluminum cathode and at low cathode to anode surface area ratio (0.5:1). This research suggests that these electrochemical techniques could be used in tandem with existing septic tank systems to improve effluent quality.