Portable Silt Density Index (SDI)Test Kit

All membrane manufacturers recommend an SDI of less than 5 to prevent irreversible fouling of membranes.

In order to measure the degree of this fouling problem, a concept called silt density index or SDI is used. Here filtration rates are calculated by exposing a 0.45-micron filter to the feed water under pressure and filtration rates are calculated. With Aquacorp’s SDI test kits, you can get a clear measure of the degree of suspended solids and colloidal materials you have in your feed water.

In most cases, an SDI of less than 5 is considered acceptable for the reverse osmosis systems. Determining the SDI value would be instrumental in investigating relevant water purified technology or device which under ASTM method 4189-95 is generally accepted.