Increase knowledge! Take a look at the solution to the pollution of laboratory ultrapure water consumables

      Nowadays, in most laboratories, laboratory ultra-pure water devices are used, because the water quality in different regions is different, and the pollution of water purifiers in areas with poor water quality is more serious than that in areas with better water quality. cause device performance degradation. At this time, it is necessary to clean the equipment to restore its performance.

During the use of the laboratory ultrapure water device, in addition to the normal performance degradation, the performance degradation of the equipment due to pollution is more serious. The usual pollution mainly includes chemical scale, organic matter and colloid pollution, and microbial pollution. Different types of pollution show different symptoms. There are also some differences in the symptoms of membrane fouling proposed by different membrane companies.

In the project, we found that the length of the pollution time is different, and the symptoms are also different. For example, when the membrane is polluted by calcium carbonate scale, when the pollution time is one week, the main performance is that the desalination rate drops rapidly, the pressure difference increases slowly, and the change of water production is not obvious. Cleaning with citric acid can completely restore the performance. The pollution time is one year (a water purifier), the salt flux increases from 2mg/L at the beginning to 37mg/L (raw water is 140mg/L~160mg/L), and the water production decreases from 230L/h to 50L/h , after cleaning with citric acid, the salt flux decreased to 7mg/L, and the water production increased to 210L/h. Furthermore, pollution is often not single, and its symptoms are also different to some extent, making the identification of pollution more difficult. To identify the type of pollution, it is necessary to comprehensively judge the raw water quality, design parameters, pollution index, operation records, equipment performance changes and microbial indicators:

(1) Colloidal pollution: When colloidal pollution occurs, it is usually accompanied by the following two characteristics: A. The microfilter is blocked very quickly in the pretreatment, especially the pressure difference increases rapidly. B. The SDI value is usually above 2.5.

(2) Microbial contamination: When microbial contamination occurs, the total number of bacteria in the permeate water and concentrated water of the RO equipment is relatively high, and it is usually not maintained and disinfected as required. All water treatment equipment is the same. In the long-term use process, the most important thing is maintenance. The use of correct maintenance measures will help prolong the service life of the equipment.