Cleaning and Replacing of RO Plant Filters

According to some studies, a 3.5 million of home-based RO plant was sold in 2017 in India and the market for RO plant manufacturers is developing with a CAGR of 17-20% annually. RO plant water purification system is most commonly used for water purification across India. So the question is that how the RO plant filters can be cleaned and what is the right time to replace these filers.

When RO plant filters need to be replaced?

To make your RO plant work properly a routine maintenance is required. RO plants usually have 3-5 filters depending upon the model and specifications given by RO plant manufacturers. Here we will discuss an overall overview of filters that will be applicable to almost all the RO plants.

The first stage of the RO plant consists of a membrane used for pre-filtration. This membrane is designed to filter all the sediments including silt, dirt, and sand. This filter can be replaced after 6-9 months and if it is not replaced then it can result in clogging of sediments making RO membranes unsafe.

The second filter is generally known as carbon filter and is designed to get rid of chlorine and other contaminants that can change taste and odor of water.

The third phase is the actual RO phase. Reverse osmosis is basically a procedure in which water is passed through a membrane with the help of external pressure. The membrane is designed in such a way that It allows only pure water to pass through it, leaving all the impurities behind. This is the exact opposite of natural osmosis. The amount of water passed through the membrane is usually 2 drops per second. The Ideal time period for replacing RO membranes is 2-3 years. The time can vary depending upon the nature of water.

The last and the final filter is called carbon filter and is used to polish the water at the end of purification cycle. These filters can be replaced after every 6-9 months

Cleaning of RO plant:

The cleaning of membranes and filters is necessary for the smooth working of the RO plant. There are several methods for RO plant cleaning such as air flush, backward flush, forward flush, and use of chemicals.

Forward Flush:

This method is applied to membranes and is creditworthy of opening dead ends. In this process, cross-flow filtration is performed without yielding permeates. The main purpose of this procedure is to remove the layer of contaminants from the membrane. High pressure is applied during forward flush to get the desired results.

Backward Flush:

Backward flush is a very effective technique to open the closed pores of the membrane. In this technique, a pressure is applied that is 2.5 times greater than the pressure in the production phase.

Air Flush:

This technique is used to remove fouling around the membranes. In this technique high-pressure air is applied with the forward flush, making bubbles that help in removing foul.

Cleaning by Chemicals:

When all the above mentioned procedures are not worthy enough to give desired results than cleaning is done with the help of chemicals. The procedure of chemical cleaning is very simple. Filters are filled with HCL or HNO3. After filling the filters with disinfectants some time is required for soaking of chemicals. After some time all the chemicals are flushed and filters are ready to be used for production again.

Sometimes cleaning methods are combined to get the desired results. The cleaning procedure also depends on the model of the RO plant.