Advances in Wastewater Treatment Technology

The control of environmental pollution and also the treatment of polluted water are of great concern. Within the past decade, electrochemical coagulation process has emerged as most effective wastewater treatment process as compared to conventional techniques of treating wastewater. Electrocoagulation is robust, cost effective, reliable, low sludge generating process, it has automation amenability and it has high pollutant removal efficiency. The aim of the review is to explain the basics and up to date advancement of electrocoagulation method for the improvements in the pollutant removal efficiency.

Conventional wastewater treatment technologies improve the quality of wastewater discharged into the environment and restrain polluted waters from contaminating other available clean water resources. However, these treatment technologies do not make wastewater fit for further beneficial uses in communities closer to the points of generation. Innovative and advanced technologies that can further improve the quality of wastewater are needed to overcome this limitation of conventional technologies, and to promote widespread adoption of recycle and reuse practices. Advanced treatment processes can be biological processes, physicochemical processes, or a combination of both (hybrid processes). Biological processes to remove nutrient pollutants such as nitrogen and phosphorus, provide the platform for further wastewater treatment to reusable quality. Physicochemical processes such as deep-bed filtration, floating media filtration, and membrane filtration, play a major role among treatment technologies for water reuse. Membrane filtration has significant advantages over other processes since they produce high quality effluent that requires little or no disinfection with minimum sludge generation. The hybrid processes attempt to obtain the benefits of both biological and physicochemical processes in one step.

The United Nations’ Sustainable Development Goal 6 (SDG 6) aims to ensure the availability and management of water and sanitation for all, including an end to open defecation, by 2030.1 Lack of access to clean water and proper sanitation affect all aspects of human life across the globe, having the largest negative effects on least developed countries and marginalized communities. About 36% of the global population live in water-scarce regions, with more than two billion people having no other choice but to consume contaminated water. Water pollution is the greatest culprit in ecosystem destruction, leading to biodiversity loss with often irreversible consequences. Water scarcity is expected to displace 700 million people by 2030, while desertification will put the livelihood of one billion people living in 100 countries across the world at risk by 2050.2 Despite these risks, our society has very few incentives to consume less water, maintain water quality, or allocate funding and resources to ecosystems or social objectives.3 In order to fulfill the objectives of the SDG 6, the High Level Panel on Water called for a “fundamental shift in the way the world looks at and manages water”, noting that a 40% shortfall in water availability by 2030 could be expected if no action is taken.4 An urgent need to develop innovative approaches to solve global water scarcity and quality issues has arisen, as traditional financing solutions and technologies have proven to be insufficient in addressing these challenges.

Hybrid processes combining activated carbon and nanofiltration have been studied to identify the optimum solution for advanced wastewater treatment in high quality water reclamation and reuse. With a focus on the removal of bulk and trace organic compounds the investigation identified three promising process combinations, namely powdered activated carbon followed by nanofiltration (PAC/NF), granular activated carbon followed by nanofiltration (GAC/NF) and nanofiltration followed by granular activated carbon (NF/GAC). The removal potential was examined in lab and pilot scale for a range of refractory pharmaceuticals and industrial chemicals typically detected in effluent in trace concentrations ranging from ng/L to μg/L. Fluorescence excitation emission spectroscopy was employed for the investigation of the fate of effluent organic matter. The optimum strategies for operation of the hybrid processes were determined in pilot scale. The experiments were conducted at the Wastewater Treatment Plant Aachen Soers providing an effluent of high quality with low dissolved organic carbon (DOC) concentrations of about 5 mg/L.

Abstract: the Sewer Design Guide is a guide for the engineer when planning and designing wastewater facilities and should be used for both public facilities and private facilities which serve multiple lots. This guide summarizes and outlines relevant City policies, applicable codes, and engineering and operational practices and procedures that have been developed in an effort to establish a cost-effective, reliable, and safe wastewater collection system. Also to be considered and used in conjunction with this design guide are all applicable current standard drawings, specifications, codes, laws and industry requirements for the planning and design of wastewater infrastructures