Reverse Osmosis (RO) is a separation approach that is appropriate for a broad range of applications, especially when salt and/or dissolved solids must be removed from a solution. It is among the most typical forms of water treatment.
According to Anelia Hough, water remedy marketing consultant at Allmech, leading South African manufacturer of boilers and provider of water treatment parts, there are a quantity of factors to be considered when choosing an RO system: the customer’s capacity requirement (i.e. water usage), the day by day manufacturing capacity of the system, and the % rejection for specific contaminants within the source water.
“Beyond this, RO vegetation require correct maintenance and care to ensure they operate optimally and to extend their lifespan,” she says. “Aside from regular upkeep, the greatest way to protect a RO plant is by pre-treating water, which reduces the pressure on the RO membrane – a costly component. It additionally helps to keep away from issues like scaling and bio-fouling.”

Common Issues with RO Plants

“Factors that may affect a RO system’s efficiency include temperature, working strain, back stress, the equilibrium effect/TDS creep, p.c recovery, and, of course, the RO membrane’s permeate manufacturing and p.c rejection rankings,” says Hough.
The most common issues in RO plants include:
• Fouling: happens when contaminants accumulate on the membrane floor, effectively plugging the membrane. There are many contaminants in municipal feed water which are innocent for human consumption, but large sufficient to rapidly foul (or plug) an RO system.
• Scaling: when particles are deposited on a membrane, inflicting it to plug. As certain dissolved compounds become extra concentrated, scaling can occur if these compounds exceed their solubility limits and precipitate on the membrane floor as scale. Scaling calculations are usually solely based on the silicate concentration within the feed water.
• Biofouling: reduces actual membrane performance by way of microbial generation in a biofilm that varieties on the membrane floor.
pressure gauge : on a RO membrane, this implies a higher permeate flow and poorer high quality permeate water. Dosing of oxidant brokers, such as chlorine or hypochlorite, can reduce performance and in the end outcome in the failure of the RO membranes. Use of ไดอะแฟรม ซีล can trigger chemical damage.
• Mechanical injury: can happen when a system is pressurised too quickly, damaging the RO membrane parts. One of the most clears indicators of damages on a RO membrane is the dearth of salt rejection capabilities. There can be very often an increase of permeate move fee.
Pre-treatment may help to avoid these problems, and Hough says there are various options obtainable.
Pre-treatment Options

“When choosing a pre-filter, users should all the time look for a verified effectivity score subsequent to the micron size on the filter’s technical information sheet,” says Hough.
• Multi Media Filtration: A multi-media filter is used to help forestall fouling of a RO system. This kind of sediment filtration is right for a pre-treatment course of to any reverse osmosis system helping to make sure long lifetime of the RO membrane parts. A properly operated multimedia filter can remove particulates down to 20 microns. A multimedia filter that uses a coagulant addition can take away particulates right down to 10 microns.
• Micro Filtration: The filters used in microfiltration have a pore measurement of roughly 0.1 micron. Bacteria and suspended solids are the one element that can be eliminated through microfiltration.
• Antiscalants and scale inhibitors: There are many chemical substances that can be used as antiscalants and dispersants to enhance the operation of RO. Antiscalants are a family of chemical substances designed to inhibit the formation and precipitation of crystallized mineral salts that type scale.
• Softening by ion change: A water softener is a filtration system that removes hardness-causing calcium and magnesium minerals from water via a process called ion change. Standard water softeners are cation exchange devices. Cation trade involves the alternative of the hardness ions with non-hardness ions.
• Granular Activated Carbon (GAC) Filtration: Activated carbon removes residual chlorine and chloramines by a chemical reaction that involves a switch of electrons from the surface of the GAC to the residual chlorine or chloramines. The chlorine or chloramines find yourself as a chloride ion that’s now not an oxidizer.
“It’s additionally essential to clean the RO membrane often,” says Hough. “This entails low and high pH cleaners to remove contaminants from the membrane. We tackle scaling with low pH cleaners and organics, while colloidal and biofouling are handled with a excessive pH cleaner.”

Allmech provides the entire vary of pre-treatment and RO membrane maintenance solutions for RO vegetation, together with filtration systems, softeners, antiscalants, chemical compounds and other consumables.
“At Allmech, we’re looking ahead to rising this part of our enterprise in 2022 and beyond, leveraging our experience in all issues associated to water remedy. We even have a boiler division and we stock a complete vary of Runxin valves, so we’re properly positioned to be a one-stop store for anyone needing a water treatment or boiler specialist, and we’re expecting a busy 12 months forward,” Hough says.

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