25 - Advances in disinfection techniques for water reuse

Abstract

Publisher Summary Disinfection is the inactivation or destruction of micro-organisms that cause disease. Disease-causing pathogenic micro-organisms include viruses, bacteria, and protozoans. Although many common wastewater treatment processes reduce the concentration of microbial pathogens, it is necessary to provide a final disinfection process that ensures safe levels of pathogens. All the disinfection treatment methods that include either chemical agents or physical treatment methods are much more effective when applied to wastewater already subjected to the processes of flocculation and filtration. The latter processes reduce the chemical demand for chemical disinfectants or increase the path length of disinfecting radiation for physical treatment methods. Disinfection of wastewater is necessary to protect water quality for subsequent use. The latter would include possible use downstream as a source of public water supply or irrigating crops. Another option is the internal reuse or recycling of treated wastewater within a given industry, such as food processing. Wastewater reuse is commonly applied to the irrigation of agricultural crops. Unfortunately, the potential for disease transmission with untreated wastewater is significant, especially, if it is used to irrigate leafy vegetables. This chapter presents that wastewater disinfection of resistant microbes can be achieved with other treatment options, including chlorine dioxide, ozone, and UV radiation. It also discusses the continuous disinfection process and reactor design, scale-up, and modeling procedures for both chemical and physical disinfection methods. It further explains the common disinfection methods and other techniques.