What is a Reverse Osmosis System | Everything You Need to Know

by - 7/31/2018 06:58:00 PM

You probably have no idea about Reverse osmosis or you may hear of it, but you do not know how it works. Well, reverse osmosis is a popular tool that you can use to clean water. Usually, some people use a reverse osmosis system for business. A mineral water company uses a reverse osmosis system to clean water before they sell the water. Now, we are going to talk about reverse osmosis system or RO system deeper so that you know what it is and how it works.

What is a Reverse Osmosis (RO) System?

Do you remember that you have learned about Reverse Osmosis system since you were at school? This process was first introduced in 1748 by a France scientist. During the test, the scientist obtained a result in which the water spontaneously diffused to penetrate a membrane toward alcohol. Then, 200 years later, some scientists finally can modify this process that is known as Reverse Osmosis. Basically, Reverse Osmosis is a process to convert dirty water to become clean water so everybody can drink it without afraid of contamination. Many people have been using this system to accommodate their clean water for residences up to spacecraft.

The Uses of RO System for Daily Life

Reverse Osmosis technology is used where pure water is needed; usually in the following places:
1.    Drinking water
2.    Humidification
3.    Ice Making
4.    Water Rinse
5.    Biomedical applications
6.    Application laboratories
7.    Photography
8.    Production of drugs
9.    Kidney analysis
10.    Chemical process
11.    Making cosmetics
12.    Restaurant
13.    Metal plating application
14.    Water filler boiler
15.    Water charger/battery
16.    Semiconductor production
17.    and many more

How Reverse Osmosis System Work

A semi-permeable membrane, like a membrane composed of cell walls or like the arrangement of cells in the bladder, is selective against objects going through it. Generally, water can go through this membrane easily because of its small molecular size and it also prevents other contaminants from trying to get through it. As experiments, you can put water on both sides of the membrane, where water on one side has different concentrations of dissolved minerals, since water has the property of moving from a low concentration solution to a higher concentrated solution, the water will move (diffuse) through the membrane from the side low concentration to the higher concentration side. Thus, the osmotic pressure will counter the diffusion process and will form an equilibrium.

The Reverse Osmosis process moves water from high contaminant concentrations (as raw water) to water reservoirs that have very low concentrations of contaminants. By using high-pressure water on the raw water side, it can create a reverse process of the natural process of osmosis. By still using a semi-permeable membrane it will only allow the water molecules through it and dispose of various dissolved contaminants. The specific process that occurs is called exclusion ions, in which a number of ions on the membrane surface as a barrier allows the molecules of water to pass through as they release other substances.

Low-Pressure RO System

What is a Reverse Osmosis System with a low-pressure? A low-pressure Reverse Osmosis system is a pressurized less than 100 psig. Usually used in residential areas that use the shelter system as in the following scheme:

First of all, the Incoming Water goes to Prefilter, after that it passes through the reverse osmosis module, and then it goes to post filter. From the post filter, the water will enter the diaphragm pressure tank before distribution. Then, from this tank, the water moves through a pipe and passes the sink top and then goes to the last point of treated water. Finally, the water is clean and everybody uses the water.

This pressurized system is capable of providing enough pressure to move water from the holding tank to the faucet. But unfortunately, it will also create counter-pressure against the membrane, which can decrease the efficiency of the system. Some units overcome this problem by using a non-pressurized tank with a pump to get purified water when needed.

Low-pressure units are usually able to produce 2-15 gallons per day, with a great efficiency of reject water up to 2 - 4 gallons for pure water produced. The purity of water produced can reach 95%. This type of system is very affordable. If you are looking for this type RO system, then you can check this post on 10lista. This type of unit requires maintenance in the form of replacement of pre and post filter (usually 1 to 4 times per year); and replacement of Reverse Osmosis membranes every 2 to 3 years, depending on usage.

High-Pressure RO System

What is a Reverse Osmosis System with a High-Pressure? A high-pressure RO System is commonly used for commercial and industrial. The high-pressure system usually operates at a pressure of 100 - 1000 psig, depending on the membrane used and the water to be treated. This system is typically used for industry and commercial that require large volumes of clean water.

Most commercial and industrial systems use many membranes arranged in parallel to produce the desired amount of water. Water processed from the first stage then proceeded to an additional membrane module to obtain a higher purification rate. The resulting wastewater will go to the next membrane module to improve the efficiency of the system despite it still needs flushing as the concentration increases to a fouling level.

The High-Pressure system for an industry is able to produce 10 to thousands of gallons of water per day with an efficiency of 1 - 9 gallons of wastewater. Water purity can reach 95%. This system is larger and more complicated than the Low-Pressure system.

Eliminating Some Types of Contaminants

Reverse Osmosis is able to eliminate many types of health and aesthetic contaminants. It is designed effectively so as to eliminate the unpleasant taste, color and odor, and the taste of salty or sodas caused by chloride or sulfate.

Reverse Osmosis can also eliminate some specific contaminants such as atrazine, asbestos, pesticides, arsenic, herbicide, nitrate, Flouride, tin, mercury, and radium. By using an appropriate carbon pre-filter (which is usually included in many reverse osmosis systems), it will be able to remove contaminants such as benzene, trichloroethylene, trihalomethane, and radon.

This system can also eliminate biological contaminants such as Cryptosporidium. Warning from the Water Quality Association (WQA), that the reverse osmosis membrane is generally capable of removing all micro-organisms and health contaminants, by designing a reverse osmosis system that can prevent the failure of protection in drinking water systems.

*Featured Image Source: Flickr

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