The Pollution Index (SDI) value is one of the important indicators for measuring the influent of the RO reverse osmosis system. It is the main means to test whether the effluent of the pretreatment system meets the requirements of reverse osmosis inflow. Its size is crucial for the lifespan of reverse osmosis operation.
The SDI instrument, also known as the pollution index instrument, can calculate and measure the relative amount of suspended substances in the incoming water. When the water enters through 0.45 μ When m film is used, the SDI value reflects the particle matter fouling in the water by 0.45 μ The speed of the membrane with an aperture of m. American Society for Testing and Materials (ASTM) chooses 0.45 μ The reason for the M-aperture membrane is that it is easily blocked by colloidal substances rather than hard particulate matter (such as sand or scale). The SDI value usually serves as a warning to ensure that particulate matter in the influent does not contaminate the reverse osmosis membrane.
Selection guide:
1. The materials used for some important connecting components are generally better than polytetrafluoro materials and have better performance than ordinary materials.
2. The material of the filter membrane is usually included by manufacturers, depending on the material.
3. Brand is still quite important. Choosing large brand instruments ensures quality and provides comprehensive after-sales service. Of course, you can communicate more with industry professionals, and some cost-effective brands are also worth a try.