Process water, also known as process water, is water used in industry for a variety of purposes, including steam energy generation, heat transfer, waste or raw material transfer, mechanical operation, manufacturing (as raw material), ion transfer, product washing, quenching of hot products, gas flushing and pressure maintenance. In industry, according to the area of preparation, we distinguish between cooling water, boiler (feed) water and industrial waste water. Water is treated before entering the systems, i.e. before the technological processes themselves, in order to reduce pollution and improve the quality of the incoming water and avoid possible damage to the process equipment (devices) inside the system. Water treatment includes mechanical, biological and chemical treatment and disinfection, which can be carried out as one of several steps or as the only treatment step. The disinfection process is crucial for maintaining the quality of water for human use and consumption. The basic goal of disinfection is to reduce the amount of bacteria to a level that, under normal use, does not pose a danger to human health. Disinfection is considered key to preserving healthy water and has proven to be an incredibly effective treatment. Today, there are several techniques for disinfecting water, including UV radiation, ozone, and chlorine and its compounds as the most well-known techniques.