The sources of general raw water can roughly be divided into①Surface water-Rivers, lakes and reservoirs;②Groundwater-Well water;③Wastewater-Industrial wastewater and municipal wastewater;④Seawater.At present, reverse osmosis technology is commonly used in water treatment methods, among which reverse osmosis membranesROThe membrane is a crucial component. Reverse osmosis membranes are a type of membrane capable of separating substancesDissolve salts, colloids, microorganisms and organic matterA semi-permeable membrane separated from water, because of itThe system has the advantages of good water quality, low energy consumption, no pollution, simple process and easy operationIt is increasingly favored by all sectors of society. However, the market is flooded with various reverse osmosis membrane brands, and the same brand has multiple models, making it difficult to choose a reverse osmosis membrane.ThereforeHere we will discuss the matters needing attention when purchasing reverse osmosis membranes.

I. Water Quality and Quantity

   TDS(Total dissolved solidsIt is also known as the total amount of dissolved solids and is generally reflected by electrical conductivityTDSThe higher the electrical conductivity, the higher the salt content in the water.TDSThe higher.

Water production volume. The size of the membrane is generally selected based on the volume of water production.

Ii. Membrane Properties

In membrane elements, they are further classified into different models based on their distinct characteristicsROMembranes, including high-desalination membranesLow pressure/Extremely low pressure membrane,Anti-pollution membrane,Standard high-pressure type membrane,High boron removal film,Energy-saving filmAnd so, the understanding of these membranes is the sameOne of the points to note when purchasing reverse osmosis

High desalination membrane elements: Suitable for desalination and advanced treatment of conventional brackish water, surface water and tap water. It has excellent desalination performance and a very high water production capacity.

Low pressure/Extremely low pressure membrane element:Suitable for salt content approximately1000ppmThe following desalination and advanced treatment of brackish water, surface water and tap water. It has a low operating pressure (at a relatively low operating pressure, such as the test pressure)0.76/0.69MpaIt can achieve a relatively high water production capacity and a very high water output, which can greatly reduce the operating costs of the system.

Anti-pollution membrane element:It is suitable for fields where there is relatively strict pretreatment but the feed water still contains organic matter and other pollutants.

Standard high-pressure membrane element:It features world-class pressure resistance, excellent and stable desalination performance, and can ensure the acquisition of high-quality permeate from seawater under high recovery rates. It is suitable for desalination treatment of high-concentration seawater.

High boron removal membrane element: It features world-class boron removal rate and desalination rate, with excellent and stable desalination performance, ensuring the acquisition of high-quality permeate from seawater under high recovery conditions.

Energy-saving membrane elements: They feature high desalination rate, large water production flux and low operating cost, which can effectively reduce equipment investment and system operating cost.

Iii. Maintenance and Recovery Rate

    Generally speaking, performance is directly proportional to price. Some membranes may be purchased at a relatively low price, but their stability and desalination rate are not satisfactory. They often need to be replaced and maintained, which will affect the usage efficiency in both the long term and the short term. At the same time, the recovery rate is also something we should pay attention to when purchasing reverse osmosis membranes

RORecovery rate of the membrane=(ROThe water production flow rate of the membrane / Influent flow rate×100%

The recovery rate is directly proportional to the performance of the membrane. The higher the performance, the higher the recovery rate. Therefore, when purchasing, more attention should be paid to this matter.