Reverse osmosis system is used to remove large particles, molecules, and even ions from water. It usually uses in drinking water technology and other technologies which related to water purification. The process uses a semi-permeable membrane which serves to filter water from bacteria and other unwanted substances. Millions of people in the world have been using reverse osmosis filtration to provide healthy drinking water in their house. There are many reasons of why people love to use this water purification system but do they know how it works? If you are interested in it, here are some explanations on the components, how the system works, and what can you expect from it.
The Components of Reverse Osmosis System
Commonly, a water purifier in the house is installed under the sink. There are some companies which manufacture the tools but most of the RO units commonly have the same basic elements. However, even though they work the same way, the quality of the water produced can be different. The usual components that construct a reverse osmosis system are:
- Cold water line valve
This valve is attached to the water supply line which supplies the water for the system. It has a tube sticking on the inner side of the system’s pre-filter.
After going through the cold-water line, the water enters the pre-filter part of the system. It can be two or more filters inside the machine. The most common filters used in RO system are carbon and sediment filters. This process is aimed to remove dirt, silt, and other sediments to protect the membranes of the reverse osmosis system. This will also prevent the unwanted materials to enter and break the system. Carbon membranes could also remove chlorine that can damage the membranes.
- The membranes
The RO membranes are the main components of the system. They purify the water by removing a wide variety of dangerous substances on the water. After the water passes the membrane, it will be stored in a pressurized tank.
- The storage tank
Commonly, a water storage tank in RO can accommodate two to four gallons of water. It has a bladder inside to keep the water pressurized when the tank is full. The size of the tank is usually 15 inches in tall and 12 inches in the diameter.
After leaving the tank, the water should pass the post filter before it can leave the faucet. The post filter in a reverse osmosis system is commonly carbon filters. It can remove any tastes and odors that still remain from the first filtration.
- Automatic SOV (shut off valve)
The automatic SOV will close the valve immediately when the water fulfills the capacity of the storage tank. It prevents any more water to goes to the membrane. When the water in the tank goes out, the auto SOV then opens the water flow to bring the water to the membrane. It is done while the wastewater is discharged into the sewer.
- Check valve
It is the valve located between the membrane and the tank. It avoids the water to flow back to the membrane because the pressure in the tank is higher. The backward water flow could crack the membrane.
- Flow restrictor
The water flowing in the reverse osmosis system is maintained at a certain flow rate so it will produce the highest quality water. You can find many styles of flow controls in order to produce water with certain quality. The flow restrictor is also used to keep the pressure on the inner side of the membrane.
Commonly, the faucet uses in RO units are the non-air gap models but some use air gap faucet because of the regulation in the area. It is usually placed in the kitchen sink.
- Drain line
The line connects the membrane space to the drain. It is used to dump the wastewater resulted from the reverse osmosis system.
Four Stages of the RO Process
Actually, there are four processes that happen inside the RO water filter unit.
- Sediment filter
The first process is the sediment filter which occurs in the pre-filter stage. It is when the sediment, dirt, and silt are filtered to prevent them from breaking the membranes.
- Carbon filter
The second process in the reverse osmosis system is aimed to get rid of chlorine and other dangerous contaminants which can reduce the effectiveness of the membranes. It also removes the odor and improves the water taste.
- Reverse osmosis membrane
It is the process where the water is allowed to go through the membrane without any additional contaminants.
- Polishing filters
It is the last process where the RO unit polishes the water and make sure there are no remaining odor and taste.
These processes in the reverse osmosis system ensure you will get the best drinking water that will make your health better. To keep the quality of the water, you need to replace the membranes periodically every six months, one year, or two years depending on the filters type, the volume, and the quality of the water.
Commonly, the sediment or carbon filters in pre-filter and post-filter should be replaced every six to twelve months. While the RO membranes should be replaced every two or three years. However, there are so many products in the market and every reverse osmosis system unit has their own rules for parts replacement. They are usually listed under the product’s specifications or on the manual books. If the RO unit is treated properly, the system can work well for at least ten to fifteen years.
Most of the RO units do not need electricity for operation. They just need the water pressure for running. However, there are some larger units that need electricity for the water pump but the power used are just minimal. Reverse osmosis system can be the cheapest solution to provide the best drinking water for your family. It is very efficient, safe, and only needs simple maintenance to ensure the quality of the water produced.