Apart from scaling, these physical damages to reverse osmosis are even more fatal!

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The core of an osmosis system is a precision membrane element, whose physical components (such as the membrane sheet, water inlet screen, product water central tube, housing, etc.) are very fragile. Improper operating conditions can cause irreversible physical damage to it. Many damages are not caused by chemical scaling or contamination, but rather directly by physical forces, mechanical actions, or improper handling. 1. Mechanical wear and scratches on the diaphragm: Pre-treatment defects are the most common cause of such damage. If the pretreatment processes (such as multi-media filters and ultrafiltration) fail or become less efficient, and are unable to effectively remove suspended solids, colloids, or small hard particles (such as sand and metal oxide fragments) from the water, these hard particles will enter the membrane elements along with the high-pressure water flow. Inside the membrane element, the water flow passes through narrow inlet screens under high pressure; the particles carried along cause intense friction and scraping on the membrane surface, similar to continuous rubbing with sandpaper, which results in scratches and wear of the polyamide desalination layer on the membrane surface. This type of damage leads to a significant decrease in the system’s desalination efficiency: once the dense desalination layer on the membrane surface is damaged, the salt permeability increases sharply, resulting in an increase in the conductivity of the produced water. Abnormally increased water production: When the membrane surface is scratched, the water flux increases, but this comes at the expense of the desalination efficiency. After removing the scrapped membrane elements, it is common to see shiny, smooth scratches on the surface of the membrane, rather than its normal matte surface. Preventive measures: Strictly ensure the effectiveness of the pretreatment process, so that the SDI (Sediment Discharge Index) value remains below the requirements for water entering the RO membrane (usually SDI