Brand:Millipore, USA

model:MILLIPORE ZLFI00001

The Pollution Index (SDI) value, also known as FI (Fouling Index) value, is one of the important parameters of water quality indicators. It characterizes the content of particles, colloids, and other objects in water that can block various water purification equipment. By measuring the SDI value, the corresponding water purification technology or equipment can be selected. According to ASTM method 4189-95, this method is widely recognized in the industry.

In the process of reverse osmosis water treatment, SDI value is one of the important indicators for determining the inlet water of the reverse osmosis system; It is the main means of verifying whether the effluent from the pre-treatment system meets the requirements for reverse osmosis inlet water. Its size is crucial for the operational lifespan of reverse osmosis systems.

The SDI value measures the attenuation of flow velocity through a membrane with a diameter of 47mm and a pore size of 0.45 μ m. The reason for choosing a membrane with a pore size of 0.45 μ m is that at this pore size, colloidal substances are more likely to clog the membrane than hard particles such as sand and scale.

The attenuation of flow velocity is converted into a value between 1 and 100, which is the SDI value. The lower the SDI value, the smaller the tendency for water to contaminate and block the membrane. Considering both economy and efficiency, most reverse osmosis manufacturers recommend that the SDI value of the reverse osmosis inlet water should not exceed 5.

Millipore ® The SDI analyzer system includes a pressure reducing valve, a 47mm membrane changing filter, a diaphragm, and some necessary valves, connecting pipes, and fittings. The system includes a box of mixed cellulose filtration membranes that fully comply with the requirements of ASTM methods. Using this device, only a measuring cylinder and stopwatch need to be prepared to measure SDI values online.

Measuring cylinder, 500ml, PP, minimum scale 5ml. stopwatch, accuracy 0.2 seconds. 47 mm diameter, 0.45 μ m pore size MF Millipore mixed cellulose ester filter membrane, consumables