Reverse osmosis is one of the most effective water filtration methods. RO systems can be used in various fields, such as outdoor, domestic, industrial, etc. Why is reverse osmosis so popular? The main advantages are very prominent. Below you'll learn how reverse osmosis works, what impurities it can remove, and RO-related uses.
Reverse osmosis definition
Reverse osmosis (RO) is a membrane separation process in which water is pressurized along the surface of the membrane. Purified water passes through the membrane and is collected, while concentrated water, containing dissolved and undissolved substances that cannot pass through the membrane, is discharged to the drain pipe.
The key requirements of the reverse osmosis process are that the membrane and water are under pressure and other substances are pre-filtered to remove suspended impurities and carbon and to remove gas (which damages the membrane). Most membranes remove 99% of dissolved impurities, depending on the composition of the impurities and water.
Reverse osmosis systems (RO) remove salts, microorganisms, and many high molecular weight organics. System capacity depends on the total dissolved solids in the water temperature feed water, the operating pressure, and the overall recovery of the system.
How does reverse osmosis work?
A film that is selective to the permeable substance is called a semi-permeable film, and a film that can only pass through the solvent but not the solute is generally called an ideal semi-permeable film. When the same volume of a dilute solution (such as freshwater) and concentrated solution (such as salt water) are placed on both sides of the semi-permeable film, the solvent in the dilute solution will naturally flow through the semi-permeable film and spontaneously to the concentrated solution side, this phenomenon is called osmosis. When osmosis reaches equilibrium, the liquid level on the concentrated solution side will be a certain height higher than that of the dilute solution, that is, a pressure difference is formed, and this pressure difference is the osmotic pressure. The size of the osmotic pressure depends on the inherent properties of the solution, that is, it is related to the type, concentration, and temperature of the solution and is independent of the properties of the semi-permeable film. If a pressure greater than the osmotic pressure is applied on one side of the solution, the flow direction of the solvent will be opposite to the original direction of penetration and begin to flow from the concentrated solution to the dilute solution side, this process is called reverse osmosis.
Reverse osmosis is a reverse migration movement of osmosis, which is a separation method that separates the solute from the solvent in the solvent without the help of the selective interception of the semi-permeable membrane under pressure drive. It has been widely used in the purification and dissolution of various solutions, among which the most common application example is in the water treatment process. Using reverse osmosis technology to remove ions, bacteria, viruses, organic matter colloids, and other impurities in the water to obtain high-quality pure water.
Related: How Does Reverse Osmosis Water Filter Work?
The benefits of reverse osmosis
Reverse osmosis (RO) is an effective and widely used water treatment process with many advantages that make it ideal for drinking water, industrial water, and other applications. Here are some of the benefits of reverse osmosis water filtration:
- Efficient removal of impurities: RO can effectively remove a wide range of impurities in water.
- Improve taste and smell: After removing impurities, the taste and smell of the water will be significantly improved.
- Environmentally friendly: RO has a relatively low energy consumption and does not require the use of a large number of chemicals, reducing environmental pollution.
- Operation and maintenance: RO operation is relatively simple, RO membrane components are easy to replace, and adapt to various application scenarios.
What contaminants can RO remove?
Reverse osmosis (RO) technology can effectively remove a variety of pollutants in water, and the following are the main categories of pollutants that RO can remove:
- Dissolved salt, a removal rate of more than 99%, including calcium, magnesium, sodium, potassium, chloride, nitrate, etc., effectively reduces the hardness of water and TDS(total dissolved solids).
- Organic matter, removes most organic matter, such as pesticides, insecticides, drug residues, etc.
- Microbial, effectively removes bacteria, viruses, parasites, and other microbial pollutants, to ensure water safety.
- Heavy metals, removal of lead, mercury, arsenic, and other harmful heavy metals to ensure drinking water safety.
- Particulate matter, such as sediment, silt, and other suspended solids.
- Drugs like hormones and antibiotics.
- Radioactive elements such as radium and uranium.
What pretreatment is required for reverse osmosis systems?
The main purpose of reverse osmosis pretreatment is to remove impurities such as suspended matter, colloids, organic matter, bacteria, and microorganisms in the water so that the water quality can meet the intake requirements of the reverse osmosis membrane, protect the reverse osmosis membrane from pollution and damage, to extend the service life of the membrane and improve the quality of the water produced. At the same time, pretreatment can also reduce the subsequent membrane cleaning and replacement frequency, saving operating costs.
How to prevent organic matter from reverse osmosis system
Organic matter is the enemy of reverse osmosis membrane, long-term accumulation will lead to membrane pollution and performance decline. Therefore, pretreatment needs to use oxidant or adsorbent and other processes to effectively remove organic matter. At the same time, to reduce the burden of reverse osmosis membranes, the double membrane method can also be considered for pretreatment.
How to prevent microorganisms in reverse osmosis system
The water quality may contain microorganisms such as bacteria and viruses, which will multiply on the reverse osmosis membrane, resulting in decreased membrane performance. Therefore, pretreatment needs to use ultraviolet sterilization, ozone sterilization, and other processes to effectively remove microorganisms. At the same time, to prevent the breeding of bacteria and microorganisms, it is also necessary to regularly clean and disinfect pretreatment equipment and pipelines.
Do reverse osmosis systems waste a lot of water?
RO systems do produce wastewater, but they are not "wasted." Most RO systems produce about 4 gallons of wastewater for every gallon of water they produce. It mainly intercepts impurities in water through membrane separation technology, and these water-containing impurities are concentrated water. At the same time, you can use this concentrated water for washing, watering flowers, etc., to achieve resource recycling. So there is no waste of water.
How to reduce water wastage in RO?
Worried about RO water purifier water costs? There are ways to reduce wastewater discharge.
- Choose an RO membrane with a high recovery rate, which can directly reduce waste water generation.
- Install a penetrant concentrator, which recycles some of the water in the wastewater, thereby reducing the overall wastewater volume.
- Regular system maintenance, which requires regular cleaning or replacement of RO membranes, filters, and other components, keeps the system running efficiently and reduces waste water.
How often does a RO system drain?
The frequency with which an RO system drains water depends on many factors. Different types of RO systems drain water at different frequencies. The worse the inlet water quality, the more wastewater the RO system needs to discharge. The greater the water consumption, the more frequently the RO system will drain.
Is an RO system better than bottled water?
Which is better, RO system or bottled water depends on your specific needs and preferences. In general, the RO system is cheaper than bottled water, it can remove most of the harmful substances in the water, using the RO system can enjoy filtered pure water at any time, without the need to buy and store bottled water in advance. Bottled water is easy to carry, and you can choose different brands of bottled water with different flavors. However, the quality of bottled water is difficult to guarantee, and there may be bacteria, microplastics, and other pollution.
The best reverse osmosis water filtration system recommendation for 2024
There are many reverse osmosis water filtration systems on the market, but few can achieve the best filtration results. ITEHIL's reverse osmosis filtration system is the first choice for many users with a filtration effect of 99.99%. With a portable design, built-in 2*6000mah battery, and USB-C charging, you can get healthy pure water anytime, anywhere.
ITEHIL reverse osmosis water filtration system uses PP cotton + activated carbon +RO membrane multiple filtration, which can filter almost all harmful substances in the water and retain some minerals. At the same time, it can filter fresh water in different environments. Ideal for outdoors and at home.
How many years does a RO system last?
The service life of an RO system depends on many factors. If you choose an ITEHIL reverse osmosis system, it will generally last 15 years. But you need to change the water filter cartridge regularly, and the ITEHIL reverse osmosis system consists of RO and mixed filter, RO filter 600-800 gallons, and mixed filter 300-400 gallons.
Frequently asked questions
Is reverse osmosis water the same as distilled water?
RO water and distilled water are both a way to obtain purified water, but their production processes are different. RO is a semi-permeable membrane that removes harmful substances from water. Distillation works by boiling water and collecting steam. The steam leaves behind impurities that condense back into the water. But the filtered water from both is pure water.
Is reverse osmosis water good for coffee?
Reverse osmosis water is pure water. Can be used to brew cold brew coffee.
Does a reverse osmosis system need to be plugged in?
If you are choosing ITEHIL Reverse Osmosis water purifier with a built-in 2X6000mah battery and USB-C charging, you can enjoy drinking water anywhere with the click of a button.
How often should l change reverse osmosis filters?
Choosing a ITEHIL reverse osmosis water purifier only requires regular replacement of the water filter cartridge, ensuring clean and safe drinking water, while maintaining the best filtration results and service life of the filter.
Does a reverse osmosis system remove chlorine?
Yes, reverse osmosis systems can be very effective at removing chlorine from water.
