Several problems of ultraviolet disinfection and sterilization in water treatment

Most of the ultraviolet water treatment equipment use the traditional low-pressure ultraviolet lamp technology, and some large waterworks use the low-pressure high-intensity ultraviolet lamp system and medium pressure high-intensity ultraviolet lamp system. The number of lamps may be reduced by more than 90% due to the generation of high-intensity ultraviolet light, so as to reduce the floor area, save the installation and maintenance costs, and make the ultraviolet disinfection method more effective for the treatment of poor water quality Effluent is also applicable.
Ultraviolet sterilizer
However, there are still some problems in the use of ultraviolet disinfection lamps for water treatment
(1) Ultraviolet disinfection method can not provide the remaining disinfection capacity. When the treated water leaves the reactor, some microorganisms killed by ultraviolet will repair the damaged DNA molecules and regenerate the bacteria under the mechanism of photoreactivation. Therefore, it is necessary to further study the principle and conditions of photoreactivation and determine the minimum intensity, time or dose of ultraviolet radiation to avoid photoreactivation.
(2) The cleaning of quartz casing outer wall is the key to operation and maintenance. When the sewage flows through the ultraviolet sterilizer, many inorganic impurities will precipitate and adhere to the outer wall of the casing. Especially when the content of organic matter in sewage is high, it is easier to form fouling film, and microorganisms are easy to grow to form biofilm, which will inhibit the transmission of ultraviolet light and affect the disinfection effect. Therefore, it is necessary to adopt reasonable anti scaling measures and cleaning devices according to different water quality, and develop UV disinfector with automatic cleaning function.
(3) At present, the domestic water treatment germicidal lamp UV lamp implements the national industry standard of straight tube quartz UV low-pressure mercury disinfection lamp. The maximum power of the lamp is 500W, and the effective life is generally 5000h. The effective operation time of imported low-pressure lamp can reach 8000-12000h, and that of medium pressure lamp can also reach 5000-6000h. In contrast, the use of domestic lamps will increase maintenance costs. Therefore, it is urgent to develop long-life ultraviolet lamps or directly introduce foreign advanced ultraviolet lamp production technology. Guangzhou chenao Technology Co., Ltd. is specialized in producing all kinds of ultraviolet germicidal lamps for water treatment. The process is good, and the quality and performance are relatively stable.
(4) In the current bidding for ultraviolet disinfection system of sewage treatment plants in China, due to the introduction of a large amount of industrial sewage, the chroma of sewage discharged from some sewage treatment plants is deepened. However, the ultraviolet transmittance parameters of sewage in the bidding documents are still based on the values provided by foreign countries, resulting in a great difference with the actual situation of domestic sewage, leaving difficulties for the operation of ultraviolet equipment to meet the disinfection requirements in the future There are many obstacles.