The economics of the UV system is determined by the following factors: equipment cost and life; electrical efficiency; degree of reduction in sterilization effect during operation; electricity costs, etc. The economic analysis of the ultraviolet disinfection system has not yet reached a conclusion. There are many analysis reports with different conclusions. There are opinions that the ultraviolet disinfection device consumes a lot of electricity, and the maintenance and cost of the equipment are high. For large systems, the equipment investment is higher than that of the ozone system, and the operating cost is similar to that of ozone; but for the small system of pure water production, the investment is lower than that of the ozone device. There are also opinions that for treatment scales of thousands of tons/day or more, the investment and operating costs of the UV disinfection system are very advantageous, which are much lower than the cost of chlorination and ozone disinfection. For example, there are analytical data reports that when building a small drinking water treatment plant with a population ranging from 10 to 25,000, the approximate ratio of ultraviolet, chlorine dioxide and ozone disinfection costs is 1:4: (8-9), for a population greater than For 500,000 social organizations, the cost ratio is about 1:2.5:2.5.
These cost estimates do not include the additional cost of removing disinfection by-products and cryptosporidium cysts when using non-UV disinfection processes. In addition, analysis data shows that the investment and operating costs of ultraviolet disinfection are lower than that of chlorine disinfection, and the disinfection cost is about half of that of chlorine, but the difference is reduced with the expansion of water treatment scale.
In France and the former Soviet Union, ultraviolet disinfection was limited to small equipment. The large equipment established was to install ultraviolet lamps in series in the mains of filtered water. In the United States, ultraviolet disinfection is also limited to small equipment and swimming pools, and is often combined with other disinfectants. However, it has been reported in practical applications that the scale of drinking water plants using ultraviolet disinfection has exceeded 1.5 million tons per day.