Removal of biological and chemical contaminants using ozonization and UV photolysis

Advanced oxidation processes (AOPs) cover a whole range of methods for removal of organic materials from wastewater based on hydroxyl radicals (·OH), which is a strong oxidant. AOPs play important role in so called tertiary water treatment, i.e. elimination of pharmaceuticals, hormones or pesticides at the outflow from the wastewater treatment plant. They can exploit addition of chemicals (e.g. addition of hydrogen peroxide, Fenton reaction) or they can be of physical or physical-chemical nature (e.g. UV irradiation, ozone, photocatalysis, low temperature plasma, cavitation). The ultimate goal is complete mineralization of the organic compounds into water, carbon dioxide and inorganic salts. Paper presents a critical overview of AOPs focusing on their advantages and disadvantages, field of possible applications, especially those which are based on ozone and UV lamps or their combination. Development of new device and test circuit, combining ozonization and UV LED irradiation is presented.