Four main processes for producing pure water in pure water production lines

1. Raw water and pretreatment: The reverse osmosis treatment device has strict requirements on the quality of the influent water, so it should be handled well. In addition to multi-media filtration, activated carbon adsorption, but also pay attention to a number of indicators of water quality. Control at any time within the scope of the permit to avoid damage to the reverse osmosis membrane. If the residual chlorine in the water should not exceed 0.1mg/Kg, NaHSO3 can be added to adjust the control; if the concentration of calcium ion and sulfate ion in the water is high, sodium hexametaphosphate should be added; if the turbidity pollution index is high, microfiltration should be strengthened; In addition, the temperature, pH, etc. of the water should also be controlled within the scope of the process requirements.

2. Reverse osmosis treatment: The core component of the reverse osmosis treatment device is a membrane made of a selective material in the reverse osmosis element, that is, a very fine pore on the reverse osmosis membrane, and the pore diameter is about ten nanometers. When working, the processing water is processed so that the water molecules pass through the membrane under pressure, and the separation and purification of the water quality is played. The treatment method of reverse-infiltrating such "concentrated water" (substituted water) into pure water is called reverse osmosis process, and the reverse osmosis membrane has polyamide membrane, cellulose acetate membrane, polysulfone membrane, and composite membrane according to different materials. Wait. The structure is also hollow type, roll type, etc. At present, the application of Zui is a composite film. The advantage is that the salt rejection rate is high (up to 98%) and the applicability is good.

3. Sterilization: The water after reverse osmosis treatment needs to be sterilized. The sterilization methods include ultraviolet sterilization and ozone sterilization. UV sterilization is a mechanism that strongly destroys microbial DNA by using ultraviolet light with a wavelength of 250 to 260 nm. Ultraviolet-emitting mercury lamps are used to achieve sterilization effects; ozone sterilization is achieved by producing ozone and using the strong oxidizing properties of ozone to kill bacteria. At present, there are many ways to sterilize ozone in the production of pure water in China.

4. Fine filtration: Usually, the water after sterilization needs a 0.22 um microfiltration device to remove impurities such as bacteria remaining in the water, that is, to make pure water.