There are many benefits of having a reverse osmosis filtration system, but we are often asked "How does it work?"

January 14, 2021

Reverse osmosis is a method that can be applied to water filtration to help remove other minerals, substances, molecules and impurities from the water that runs throughout your house. RO systems vary depending on brand and design, but in general, they perform the following functions: pre-filtration, reverse osmosis, drainage and storage.

Here are the steps of water filtration through a reverse osmosis drinking water system:

Step 1: Pre-Filtration

The system connects to drinking water lines and uses a high-pressure pump to propel feed water through. Feed water passes through a series of filters, usually carbon-based, designed to "catch" sediment and mineral deposits before flowing into the reverse osmosis chamber.

Step 2: Reverse Osmosis

Here, the feed water is pushed through the semipermeable membrane.

Think of the membrane as a tightly woven piece of fabric-one that looks virtually impermeable to the naked eye. To give you an idea of how stringent the membrane is, the diameter of a strand of human hair is roughly 100 microns wide. But, in Culligan RO Systems, the spaces in the membrane are approximately ONE micron wide.

Step 3 + 4: Drainage & Storage

The system drains out all contaminants not caught in filters at each stage, and treated water is stored in a small tank until used.

One micron semipermeable membrane

What Are Common Contaminants Removed By Reverse Osmosis (RO)?

A high-performing RO system can remove up to 99% of dissolved contaminants found in feed water. These common water contaminants include:

• Salts
• Particles
• Colloids: oil and fat-based molecules
• Organic bacteria
• Pyrogens: protein-based substances produced by bacteria that cause fevers when introduced into the human body

 

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