Water treatment with reverse osmosis
Reverse osmosis systems are mainly know for their ability to turn salt water into drinking water. Many don’t know that this system is also used for water purification. Reverse osmosis can get rid of organic and inorganic contaminants, bacteria and viruses.
As you may already have guessed the system is based on the process of osmosis. This involved water moving from one container to another through a membrane. This is done with the help of pressure, to force the water from passing through the membrane. Cleaner water collects into one of the container.
Although the process is very efficient, not all compounds can be removed from the water. It all depends on the different properties of the pollutants. Also membrane types and operating conditions are important.
If you want to see some numbers, well, some membranes can filter up to 90% of the compounds. But, let’s take an example and say that a certain membrane can filter 90% of nitrates. In case the concentration of nitrates is of more than 100mg per liter, then the amount filtered can drop to 10%. That is why, reverse osmosis is usually used with other purification systems.
Like every system, it will require some maintenance. Filters will need to be replaced once in a while and also periodic cleaning will need to be done.
The main disadvantage is that reverse osmosis waste high quantities of water. It can waste up to 70-90% of the filtered water. But you can reduce this quantity by increasing the pressure difference.