There are significant differences between the primary reverse osmosis device and the secondary reverse osmosis device in terms of working principle, filtration effect, application field, equipment price, etc.

The primary is suitable for general water quality needs and has a lower cost; the secondary filtration effect is better and is suitable for high-demand occasions, but the cost is higher.

Specific needs and water quality should be considered when choosing.

There are significant differences between the primary reverse osmosis device and the secondary reverse osmosis device in many aspects. The following is a detailed explanation of these differences:

Working principle: Primary reverse osmosis device: also known as monopolar reverse osmosis, is a single-stage membrane filtration operation that uses a high-pressure pump to transport source water to the reverse osmosis device through a pretreatment system and a precision filter.

Single-stage reverse osmosis equipment

Secondary reverse osmosis device: also known as bipolar reverse osmosis or secondary reverse osmosis, it first performs coarse filtration on the source water through a pretreatment system, and then enters the precision filter. After the pressure of the primary high-pressure pump, the water first passes through the primary reverse osmosis system, and the generated water then enters the secondary reverse osmosis system again through the pressure of the secondary high-pressure pump for secondary filtration.

Double-stage reverse osmosis

Filtration effect:

First-stage reverse osmosis device: It can remove inorganic ions, bacteria, viruses, organic matter and colloids in raw water, but the filtration effect is relatively limited.

Second-stage reverse osmosis device: Because it has been filtered twice by the reverse osmosis membrane, its filtration effect is more significant. It can remove more than 98% of soluble salts and more than 99% of colloids, microorganisms, particles and organic matter in water, so that the water quality is significantly improved.

Microorganisms.

Application areas:

First-stage reverse osmosis device:

Desalination of bitter salt water, drinking water in high-fluoride areas, and high-hardness drinking water: The first-stage reverse osmosis device can effectively remove impurities such as inorganic ions, bacteria, viruses, organic matter and colloids in water, thereby providing high-quality pure water. This is particularly important for solving the drinking water problems in bitter salt water, high-fluoride areas and high-hardness areas.

Power industry: In the power industry, the first-stage reverse osmosis equipment is mainly used for pre-desalination treatment of boiler feed water, medium and low-pressure boiler power systems in factories and mines, and high-pressure boiler feed water in enterprises. Through reverse osmosis technology, the water quality used in the boiler system can be ensured to be pure, thereby ensuring the stable operation of the system.

Pure water for electronics, pharmaceuticals, and metal processing: These industries have extremely high requirements for water quality and require high-purity water. The first-level reverse osmosis equipment can remove various impurities in the water and provide pure water that meets industry standards.

Petrochemical industry: In the petrochemical industry, the first-level reverse osmosis equipment is often used for the preparation of process pure water for chemical reaction cooling water, chemical agents, fertilizers, fine chemicals, and cosmetics manufacturing processes.

Hospitals, life, leather making, printing and dyeing, and papermaking industries: In these industries, the first-level reverse osmosis equipment is also used for the treatment of process water to ensure the purity and stability of water quality.

Secondary reverse osmosis device:

Industrial field:

Power industry: used for pre-desalination treatment of high-pressure boiler feed water for enterprises such as boiler feed water, thermal power generation boilers, and medium and low-pressure boiler power systems in factories and mines.

Electronic industry: flushing water for electronic components such as integrated circuits, silicon chips, and display tubes.

Chemical industry: purification and preparation water for process water/chemical circulating water, chemical product sales, etc.

Pharmaceutical industry: large infusion, injection, tablet, biochemical products, equipment cleaning, etc.

Desalination of brackish water and seawater: suitable for islands, ships, offshore drilling platforms, brackish water areas.

Purified water device: primary desalination equipment sold as high-purity water.

Communities, real estate properties, schools, factories, hospitals and other enterprises and institutions: used to provide high-quality drinking water.

Food and beverage industry water: purification and preparation of drinking pure water, beverages, beer, liquor, health products, etc. Preparation of bottled water, mineral water and other filling water.

Medical water: provide high-purity water to ensure the normal operation of medical equipment and instruments.

Other process water: ultrapure water for automobiles, home appliance coating, coated glass, cosmetics, fine chemicals, etc.

Water for electroplating industry: water for cleaning workpieces and water for tank liquid.

Equipment price:

The price of secondary reverse osmosis equipment is significantly higher than that of primary reverse osmosis equipment. This is because the secondary reverse osmosis equipment requires more reverse osmosis membranes, high-pressure pumps and other related accessories, as well as more complex process flows.

Other features:

The separation process of the secondary reverse osmosis method does not require heating and has no phase change. It has the advantages of low energy consumption, small equipment size, simple process, convenient operation and maintenance, no pollution, strong adaptability, and a wide range of applications.

In summary, there are significant differences between the primary reverse osmosis device and the secondary reverse osmosis device in terms of working principle, filtration effect, application field, equipment price and other characteristics. According to specific needs and water quality requirements, a suitable reverse osmosis device can be reasonably selected.

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