Good hygiene is fundamental within all catering establishments and Comenda believes that alongside regular cleaning, this comes from the equipment used within the kitchen.

This is why we have implemented reverse osmosis technology as an option in our equipment within the Hi-Line range to ensure the highest of standards in cleanliness and flawless results.

What is reverse osmosis?

Reverse osmosis (RO) is a water purification technology which uses a semi-permeable membrane to remove ions, molecules and large particles from the water, as well as contaminants including bacteria, pesticides and fluoride. It can also remove many types of dissolved and suspended chemicals from water and is often used in the purification of drinking water to ensure it is clean, harmless and great tasting.

However, reverse osmosis is also important in the purification of water for cleaning dishes, glasses and cutlery, as it is vital that the water doesn’t contain any harmful chemicals or bacteria to ensure that items are cleaned to the best possible standards.

Understanding reverse osmosis

To understand exactly what reverse osmosis is and how it works, it is helpful to first understand how the process of osmosis works. Osmosis is a naturally occurring process where a weaker saline solution transfers into a strong saline solution.

Whereas osmosis occurs naturally without energy, reverse osmosis works by applying energy to the stronger saline solution. The semi-permeable membrane used within reverse osmosis allows water molecules to pass through but prevents the majority of dissolved salts, bacteria, ions and more to pass into the water. However, the water must be pushed through the membrane by applying greater pressure which will demineralise the water and allow for pure water to be released whilst holding back the particles and bacteria.

How does reverse osmosis work?

The process of reverse osmosis works using a high-pressure pump to increase the pressure on the salt side of the RO and force the water to the semi-permeable membrane. This then leaves almost all of the dissolved salts in the reject stream.

As the water enters the RO membrane, the water molecules pass through it; the salts and other contaminants then cannot pass. These are then released through the reject stream which then goes to drain or can be fed back into the feed water supply, to then be recycled through the RO system to save water. The water that goes through the reverse osmosis membrane is referred to as permeate or product water and usually has around 95% to 99% of the dissolved salts removed from it.

Reverse osmosis in Comenda warewashing

With Comenda equipment, our reverse osmosis demineralisation systems and water softening treatments improve the purity of water throughout the cleaning process. This means no hard water stains will be visible on items which means the need for post-wash polishing is eliminated, which can often be time-consuming for caterers, as well as the costs of repairing items if breakage occurs which can be quite often when cleaning by hand. With the need for post-wash polishing eliminated, this further improves hygiene standards.

If you have any questions or queries about reverse osmosis and how it is used within Comenda equipment, please contact our UK team via to find out more.

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