The operating conditions of Landis' ozone generators for wastewater treatment depend on the type of industry and the type of wastewater. These operating processes can be categorized in a systematic manner:
1) Entire treatment processes (chemical-only processes, chemical, biological, and combined chemical, biological, and physical processes)
2) Applications (in-house pre-treatment for water recycling, or indirect discharge of water from the user to a public *** water treatment facility, and water treatment at the end of the pipeline network for direct discharge to rivers and bays)
3) Removal of water from the water supply, and treatment of water at the end of the pipeline network for direct discharge to rivers and bays. p>
3) Removal of compounds (oxidative transformation of toxic or colored substances, reduction of composite parameters (DOC or COD), disinfection or removal of particulate matter) throughout the treatment process (chemical-only processes, chemical/biological and combined chemical/biological/physical processes).
Often a combination of ozone oxidation and biodegradable processes or advanced oxidation techniques (AOPS) are used to improve the efficiency of oxidation (e.g., O3/H2O2), which reduces ozone dosage and operating costs. Currently, in most cases, the ozone oxidation unit for wastewater is placed before the chemical oxidation in multi- and biodegradable systems, and sometimes after the chemical oxidation unit (i.e., O3-biological treatment-O3 system).
Industrial applications often use a combination of ozone oxidation and biodegradation processes, which can reduce ozone dosage and operating costs. The most commonly used gas-liquid contactors in post industrial wastewater ozone oxidation systems are bubbling tower reactors equipped with diffusers or venturi injectors, most of which operate in series countercurrent mode. Many reactors are operated under pressurization in order to achieve high ozone mass transfer rates, which in turn increases the efficiency of the overall process.