Basic Goal of Reverse Osmosis:
The basic goal of a reverse osmosis system is to clean water of almost of all its dissolved and suspended particles and make it free from polluting agents. The pathogenic elements in water are killed by UV radiation or any other method. This process wants to get the purest water. But when the clean water permeate is low or the dissolved agents are not withheld by the plant, then that means problem exists. The major problem is that there is a fault in RO system, and it is critical to identify the root cause of problem. As only identification of the problem will lead to the solution of the problem. Membrane autopsy is one of the latest methods to identify the problem of membrane.
The damage that a membrane can go through are:
1-Physical damage:
Physical damage might occur due to the leaks in pre-treatment scheme or fouling or operational issues.
The following physical damages may occur to the membrane:
- 1. Abrasion marks from fouling nature
- 2. Marks from spacer protrusion
- 3. Marks from spacer material
- 4. Polyamide layer damages due to a massive presence of fouling (mainly due to scaling processes).
- 5. Polyamide bubbles (permeate overpressure)
- 6. Telescoping
- 7. Compacted membranes
2-Chemical Damage:
Chemical damage may be caused in RO plant with the chemicals that are present in raw water or operational chemicals in the RO plant.
The chemical damages to a RO membrane are:
- 1. Dosage of oxidant agents
- 2. Use of harsh and strong cleaners
- 3. Use of extreme pH
Chlorination and chemical cleansing are both very good methods for reducing chemical damage.
3-Membrane failure due to fouling
Fouling of membrane is the most common cause of failure of RO, though fouling can be due to physical or chemical processes. To safeguard you RO membrane, you must make the membrane foul free, for that purpose many methods are employed, like pre-treatment of water before sending it to RO plant.Membrane failure can be prevented, and the performance of a membrane can be improved while it is in operation. Loss of structure incongruity of the membrane is the cause of failure. While there are various chemicals that can cause failure of RO, but chlorine is most common.
Steps to analyse reason of failure of RO membrane:
- 1. Check whether the failure is mechanical or electrical
- 2. If both checks are fine, the determine if membrane is failing
- 3. Reason of membrane failure is most important, so determine the fouling agent of the membrane
- 4. After this, search for the remedy for that particular problem and apply on the membrane.
Many different types of chemicals are present in the market which clean the pores of themembrane. This porous cleaning of membrane may increase the life of RO membrane.If these measures are taken properly, it is possible to increase the activity as well as the life span of RO plant. Proper guidelines should be followed as provided by the company.
