Precautions for the Use of UV Water Treatment

The sterilization function of UV radiation from the Sun has been learnt since the late 19th century. In the early 20th century, ultraviolet light began to appear in medical and drinking water sterilization. Later, since the 1960s, UV has been used commercially on a large scale, providing an excellent alternative to conventional chemical treatment solutions in many industries.

As an excellent sterilization method for water treatment, UV has a series of advantages that traditional chlorination treatment is incomparable. For example, when it is used, its action duration against harmful microorganisms will be much shorter than the use of chloride. UV water treatment is also easier to implement than chemical treatment methods which are also more expensive. But at the same time, when UV method is applied, some precautions also need to be understood. Therefore, here we have summarized some considerations when UV is applied for water treatment. With these precautions, you can learn more about UV water treatment and make a better use of UV water treatment in your industry.

1. Functionality of UV

The purpose of ultraviolet sterilization in water treatment is to kill bacteria, viruses and other harmful microorganisms. But UV light has no effect on the following components which are commonly contained in water. Also, their existence in water can further affect UV treatment.

Suspended Particles

UV sterilization only works better in the face of clear water. Suspended particles in the water will bring water turbidity, which will affect the UV penetration rate. These suspended particles in the water can block UV radiation, preventing it from reaching its target microorganisms. Therefore, if the water to be treated is cloudy, it needs to be pretreated before the application of UV water treatment.

Iron, Manganese and other Heavy Metal Components

Similar to suspended particles, the existence of heavy metals such as iron and manganese in water can also affect the UV penetration. They do this by the discoloring of the quartz sleeves. In addition, they will also absorb certain part of the UV radiation. The result is that harmful microorganisms in the water will receive less UV radiation. Therefore, they can ultimately affect the effectiveness of UV water treatment.

Calcium Salts and Magnesium Salts in Hard Water

The reason why water gets harder lies in the presence of chemical compounds such as calcium salts and magnesium salts. Since these salt compounds are soluble, their gradual accumulation will result in the forming of the scale on the quartz sleeves around the UV lamps. The existence of scale will greatly affect the radiation of the UV lamps, and thus affect the final treatment effect.

The above-mentioned three factors cannot be solved by the UV water treatment process. And at the same time, they will affect the function of UV water treatment. Therefore, it is essential to have them dealt with in the pre-treatment process before the application of UV.

2. Temperature and Power Supply Requests

Temperature

For the normal working of UV radiation in water treatment, temperature condition should also be considered. The optimal working temperature for UV water treatment equipment is between 20 ℃ and 40℃. Both too high and too low temperature will affect its sterilization effect. On one hand, when the temperature is too high, the radiation capacity of the UV lamps will be reduced, which will further reduce the killing rate of microorganisms. On the other hand, low temperatures also affect the intensity of the UV radiation. And meanwhile, most harmful microorganisms will be more sensitive to UV radiation when the temperatures drops. So does their resistance to UV radiation. As a result, the sterilization effect of the UV radiation is also to some extent reduced.

Power Supply

Unlike chemical treatment methods, UV water treatment will always require a power supply through its working process. The demand for electricity means that UV water treatment cannot meet certain emergency sterilization needs or water treatment demands under field conditions.

In addition, there are other factors that will affect the effectiveness of UV water treatment. Please check out our previous Blog Influencing Factors in UV Water Treatment to learn more.

3. Maintenance of the Equipment

In UV water treatment, to ensure a stable UV treatment effect, it is necessary to provide maintenance for the components of the equipment. In typical UV water treatment equipment, the most concerned components will be UV lamps and necessary waterproof components.

UV Lamps and Quartz Sleeves

The UV lamps in the best working condition and the clean quartz sleeves can ensure both a high UV radiation and a high penetration rate. Although UV lamps are durable, they are still consumables. The service life of a UV lamp is generally about 9000 hours, namely around 1 year. The radiation intensity of the UV lamps will decrease over time. Therefore, to achieve a favorable sterilization effect, UV lamps at or near the end of their service life need to be replaced. For quartz sleeves, it is recommended to make the replacement every 2-3 years. When a UV water treatment equipment is working, the UV lamps should be avoided switching on and off within a short period of time. Frequent switching on and off of the equipment will shorten their service life to a certain extent.

Waterproof Washers

In a typical UV water treatment equipment, the separation of the UV lamps and water is realized by quartz sleeves. But such separation requires both quartz sleeves and several waterproof washers, which are used to ensure a good airtightness. Therefore, tightness of these waterproof washers need also be checked in the maintenance of UV water treatment equipment.

Filters for Pre-treatment

The upstream filters of a UV water treatment equipment undertake the pre-treatment tasks of physical and biological filtration of the untreated water. Depending on the water quality, it is recommended that they should be replaced at least every 6-12 months.

4. UV and Human Health

UV radiation can cause negative side effects on human body, in which eyes and skin will be most likely to be affected. Short periods of UV exposure can cause electro-optic ophthalmitis or skin burns. Prolonged exposure of UV radiation can cause pigmentation, cataracts, etc. In severe cases it can even cause skin tumors or cancer. Therefore, when using UV water treatment equipment, the potential exposure to UV radiation should be avoided. When an ultraviolet water treatment equipment is working, the UV lamp works in a closed chamber. So, there will be no radiation hazard to human body. It should be noted that when testing and replacing UV lamps, certain rules or regulations should be followed to avoid any potential exposure to the UV lamps.

In the above, we have introduced some precautions in the use of UV water treatment equipment. Today, as an excellent alternative, UV water treatment equipment has gradually replaced the traditional water treatment methods. UV water treatment plays a great role in domestic wastewater treatment, swimming pool sterilization, beverage sterilization, food production and other fields. It is also capable of the dechlorination of tap water, which is an optimization for traditional water chlorination. In the future, through our product development and market research, Puritor will continue to provide you with more competitive UV water treatment equipment to make your purchase easier.