High-Performance Reverse Osmosis Equipment for Industrial Applications

Reverse osmosis technology was first discovered by American scientist DR.S.Sourirajan in 1950 and applied to seawater desalination. With the continuous development of technology, reverse osmosis equipment has been continuously optimized in terms of energy consumption and efficiency, becoming an important technical means of modern water treatment. Technological innovations include more efficient membrane materials, smarter control systems and more environmentally friendly maintenance methods.

Working Principle:
Reverse Osmosis (RO) is a membrane separation technology driven by pressure difference. When a pressure greater than the osmotic pressure is applied on both sides of the semipermeable membrane, water will penetrate from the high-concentration side (usually the inlet side containing impurities) through the semipermeable membrane to the low-concentration side (pure water side).

The semipermeable membrane has a very small pore size, which only allows water molecules to pass through, while almost all solutes (such as salt ions, organic molecules, colloidal particles, etc.) are intercepted. For example, in the desalination process, under the action of high pressure, water molecules pass through the reverse osmosis membrane to enter the other side to become fresh water, while impurities such as salt in the seawater are blocked on the inlet side of the membrane.

Main components:
Pretreatment system:
Mechanical filter (such as quartz sand filter): mainly used to remove larger suspended particles in water, such as mud, rust, etc. It is filled with quartz sand inside, and when water passes through, the suspended matter is intercepted by quartz sand particles.

Activated carbon filter:

removes organic matter, residual chlorine, odor and some heavy metals in water through the adsorption of activated carbon. For example, it can absorb pesticide residues, industrial chemicals, chlorine odor in tap water, etc.

Softener (ion exchanger):

If the inlet water hardness is high, the softener can remove calcium and magnesium ions in the water, reduce the hardness of the water, and prevent scale from forming on the subsequent reverse osmosis membrane surface. Ion exchange resin is usually used. When hard water passes through, the sodium ions in the resin are exchanged with calcium and magnesium ions in the water.

Precision filter (security filter):

Generally, a cartridge filter is used, and its filter element has a high precision (usually 5μm or 1μm), which is used to remove smaller particle impurities in the water, protect the reverse osmosis membrane from clogging, and ensure that only finely filtered water enters the reverse osmosis membrane assembly.

High-pressure pump:
This is a key power component of the reverse osmosis equipment. It can provide enough pressure to enable the inlet water to overcome the osmotic pressure and pass through the reverse osmosis membrane. The pressure of the high-pressure pump is usually determined according to the inlet water quality and the requirements of the reverse osmosis membrane, generally between 1-10MPa. For example, for seawater desalination, due to the high osmotic pressure of seawater, a pressure of up to 5-7MPa may be required.

Reverse Osmosis Membrane Assembly:
Membrane Element:

Common reverse osmosis membrane elements include roll membrane and hollow fiber membrane. Roll membrane is a material that rolls together reverse osmosis membrane, flow guide net and central tube. Water flows in from the outside of the membrane. Under pressure, water molecules pass through the membrane and enter the central tube, while impurities are retained on the outside of the membrane. Hollow fiber membrane is composed of many hollow fiber membranes. Water enters from the outside of the fiber membrane and pure water is obtained inside the fiber membrane.

Membrane shell:

used to install and protect reverse osmosis membrane elements, usually made of stainless steel, fiberglass or composite materials. It can withstand high pressure and provide a stable working environment for membrane elements.
Post-treatment system (configured according to specific needs)

PH adjustment device:

If the pH value of reverse osmosis effluent does not meet the requirements, the pH value can be adjusted by adding acid-base regulator.

Ultraviolet sterilizer:

used to kill bacteria and microorganisms remaining in the water to ensure the microbial safety of effluent. Ultraviolet rays can destroy the DNA structure of microorganisms, making them lose their ability to reproduce and survive.

Ion exchange mixed bed (for ultrapure water preparation):

When preparing ultrapure water, further remove the trace ions remaining in the water to make the water purer. It is to mix anion and cation exchange resins and load them in the same exchanger, which can remove anions and cations in the water at the same time.

Application field:
Drinking water purification:
It can effectively remove harmful substances in water, such as heavy metals (lead, mercury, cadmium, etc.), bacteria, viruses, pesticide residues, organic matter, etc. In the terminal treatment of urban water supply, reverse osmosis equipment can be used as an advanced water purification device to provide families with better drinking water. In rural areas, contaminated groundwater or surface water can also be purified into safe drinking water.

Industrial pure water preparation:
Electronic industry:

In the process of semiconductor manufacturing, electronic chip production, etc., ultrapure water with extremely high resistivity is required. Reverse osmosis equipment can remove impurity ions, organic matter, etc. in water, and then further purify it through subsequent ion exchange and other processes to obtain ultrapure water that meets the requirements. For example, semiconductor manufacturing requires extremely low content of particulate impurities in water, and reverse osmosis equipment can effectively meet this demand.

Pharmaceutical industry:

The pharmaceutical process has strict requirements on water quality. Reverse osmosis equipment is used to prepare pharmaceutical water to ensure that the water does not contain impurities and microorganisms that affect the quality of drugs and meets the requirements of the Good Manufacturing Practice (GMP) for pharmaceutical production.

Chemical industry:

In chemical production, many processes require the use of high-purity water. Reverse osmosis equipment can remove salt and impurities in water, provide pure solvents or reaction media for chemical reactions, and improve product quality and production efficiency.

Seawater desalination:
In coastal areas and islands where fresh water resources are scarce, reverse osmosis seawater desalination equipment is an important means to solve water problems. By converting seawater into fresh water, it provides water for residents' lives and industrial production. For example, some countries in the Middle East use reverse osmosis seawater desalination equipment to meet their demand for fresh water, and their fresh water output can account for a large proportion of the total water consumption.

Wastewater treatment and reuse:
For industrial and domestic sewage, reverse osmosis equipment can deeply treat the pre-treated sewage, remove pollutants such as soluble solids and organic matter, and make the treated sewage meet the reuse standards for industrial circulating cooling water, landscape water, etc. For example, in a printing and dyeing factory, the printing and dyeing wastewater is treated by reverse osmosis equipment, and the recycled water can be reused in certain links of the printing and dyeing process, saving water resources.

Performance advantages:
Efficient separation performance:
Reverse osmosis equipment can effectively remove a variety of impurities in water, and has a high removal rate for salts, organic matter, microorganisms, etc. For example, the removal rate of sodium chloride can reach 95% - 99%, and the removal rate of bacteria and viruses can reach more than 99.99%.

Stable effluent quality:
As long as the inlet water quality and operating parameters remain stable, the reverse osmosis equipment can continuously and stably provide high-quality pure water. The conductivity, hardness, microbial content and other indicators of its effluent water quality can be controlled at a low level.

High degree of automation:
Modern reverse osmosis equipment is usually equipped with advanced automatic control systems. It can realize functions such as automatic start and stop, pressure control, flow control, and water quality monitoring. For example, when the inlet water pressure is abnormal or the water quality does not meet the requirements, the equipment can automatically alarm and take corresponding protective measures, reducing the complexity and error of manual operation.

Small footprint:
Compared with traditional water treatment methods, such as distillation and ion exchange, reverse osmosis equipment has a smaller footprint. Especially when the treatment volume is the same, its compact structural design allows it to be installed and operated in a smaller space.

Flexibility and scalability:
Reverse osmosis equipment can be modularly designed according to different treatment water volumes and water quality requirements. The treatment capacity of the equipment can be adjusted by increasing or decreasing the number of reverse osmosis membrane components, which is convenient for equipment upgrades and modifications.

Maintenance and care:
Maintenance of reverse osmosis membranes:
Cleaning:

As the use time increases, the surface of the reverse osmosis membrane will be covered with dirt (such as calcium and magnesium scale, organic matter, microorganisms, etc.), resulting in a decrease in membrane flux. It is very important to clean the membrane regularly. The main cleaning methods are chemical cleaning and physical cleaning. Chemical cleaning is the use of specific chemical cleaning agents, such as citric acid (for removing calcium and magnesium scale), sodium hydroxide and sodium hypochlorite (for removing organic matter and microorganisms), etc., to clean the membrane according to a certain cleaning procedure. Physical cleaning includes water rinsing, sponge ball scrubbing and other methods to remove loose dirt on the membrane surface.

Replacement:

The reverse osmosis membrane has a certain service life, generally 2-5 years, depending on the inlet water quality, operating pressure, cleaning frequency and other factors. When the performance of the membrane drops to a certain extent (such as a significant decrease in desalination rate, the membrane flux cannot be restored, etc.), the membrane element needs to be replaced.

Maintenance of other components:
High-pressure pump:

Regularly check the operation of the high-pressure pump, including the pressure, flow, vibration and noise of the pump. Ensure that the pump is well sealed to prevent water leakage. According to the use of the pump, regularly replace the lubricating oil and seals.

Pretreatment system:

Regularly clean and replace the filter materials in the pretreatment equipment, such as quartz sand, activated carbon and filter elements. For softeners, ion exchange resins need to be regenerated regularly to restore their softening capacity.

Pipelines and valves:

Check whether the pipeline has leaks, blockages or corrosion. Regularly maintain the valve to ensure that it is flexible to open and close and well sealed.

Water quality monitoring and operation parameter adjustment:
Continuous monitoring of the water quality of inlet and product water is the key to ensuring the normal operation of reverse osmosis equipment. By monitoring the conductivity, pH value, hardness and other parameters in the water, changes in water quality can be detected in time and the operating parameters of the equipment can be adjusted. For example, if the hardness of the incoming water suddenly increases, it may cause scaling on the membrane surface to accelerate, and corresponding pretreatment measures need to be taken, such as increasing the operating time of the softening device. At the same time, the operating parameters of the equipment, such as the inlet water pressure, flow rate, recovery rate, etc., should also be monitored to ensure that the equipment operates within the specified parameter range.

Jiangsu Gena Environmental Engineering Co., Ltd. is a high-tech environmental engineering equipment company focusing on water treatment and chemical liquid separation, focusing on environmental protection and resource recycling. It focuses on the production and manufacturing of complete sets of landfill leachate treatment equipment, MVR evaporator equipment, complete sets of wastewater zero discharge equipment, complete sets of reclaimed water reuse equipment, complete sets of seawater desalination equipment, nanofiltration equipment and STRO/DTRO complete sets of equipment.

The company's management team has been devoted to the application of membranes and product technology development, environmental water treatment technology and equipment development, and new process development in the fields of industrial liquid purification, refining and separation in the field of landfill leachate and chemical industry for many years. It provides complete integrated solutions for more than 50 large industrial customers across the country, and has invested in more than 500 water treatment production equipment and industrial filtration production equipment. Customers are spread across multiple industries such as landfill leachate, chlor-alkali, polyvinyl chloride, coking, pesticides, smelting, and steel.

The company has obtained 27 intellectual property rights through its own development. The research and development projects include: reverse osmosis concentrated water treatment device for landfill leachate, energy-saving microfiltration membrane wastewater treatment device, landfill leachate treatment device for garbage transfer station, ultrasonic landfill leachate integrated GNSB anaerobic device, spiral water treatment activated carbon filtration device, groundwater treatment and prevention equipment, etc.