Water Treatment Systems: Reverse Osmosis

RO water treatment systems treat contamination at the point of use 

RO water treatment systems treat contamination at the point of use 

As a homeowner, if you receive your water from a private well its your responsibility ensure it provides contamination free drinking water. Annual testing can keep your well healthy and safe. Through testing you may find some issues that require water treatment. For some, having a source of treated clean water is simply a healthy choice. For others, it may be necessary to install a water treatment system to deal with the various organic and inorganic contaminants that may be present in your water. 

Water treatment systems fall into two distinct camps. A “point-of-entry” system is installed inline where your water enters your home and treats the water as it your plumbing.  A “point-of-use” system is generally smaller, more affordable, and used to treat water at a faucet. It's great for purifying water for drinking, cooking and occasionally washing.

Reverse osmosis is a common point-of-use treatment system that can handle a number of contaminants effectively. Let's answer some frequently asked questions about reverse osmosis.

What is Reverse Osmosis?

Reverse osmosis systems force water, under pressure, into a module that consists of a semi-permeable membrane and several additional filtration stages. Typically, an RO system consists of a pre-filter, which is used to catch large particles like sediment, organic cysts, chlorine and other compounds. 

Once water passes through the pre-filter stage it then passes through a semi-permeable membrane under pressure to remove additional contaminants. Finally, the water is passed through an activated charcoal filter which removes any residual taste, odor and some organic compounds before releasing the water into a storage tank that holds it for future use. RO systems generally come with a separate dedicated faucet for dispensing the purified water. Typically they are located in the kitchen, near the main sink.

How Does A Reverse Osmosis System Work?

The process is called “reverse” because pressure forces the water to flow in the reverse direction from the concentrated solution to the dilute solution, as opposed to natural osmosis where water flows from dilute to concentrated. RO removes ionized salts, colloids and organic molecules down to a weight of 100. This includes harmful bacteria, and other microbial organisms. 

RO is primarily used to treat water to be used for cooking and drinking. The process is slow and typical systems produce 3 to 10 gallons per day. 

What Are The Components of A Reverse Osmosis System?

A reverse osmosis system generally consists of a cold water line valve which connects to your kitchen's cold water line to draw water into the system. Water is then passed through a pre-filter. Some units may have multiple pre-filter stages. Most common is a sediment filter which removes large particles like sand and grit. Pre-filters may also include an activated carbon stage which is used to remove chlorine which can damage the membranes.

After pre-treatment, the water is then passed through a membrane. This is the heart of the RO system. The most commonly used membrane is spiral wound. This membrane leads to the storage tank. As water is needed, it passed from the storage tank through a final post-filter which purifies the water one last time before it is dispensed through a separate dedicated faucet for use.

Is A Reverse Osmosis System Difficult To Maintain?

No. RO systems require minimal maintenance. The pre-filter, membrane and post filter need to be changed and are all easy to replace self-contained units. The frequency of filter changes depends on the amount of use your system receives. 

There are a number of options available when it comes to residential RO systems. They are a point-of-use system that generally is placed under a counter near your kitchen sink. Some models can be installed on top of the kitchen counter. Counter models are inexpensive, portable and can be used in other locations in your home. Under sink models produce treated water more quickly, in greater quantities. If you have a large family, an under sink system may be the best choice. If you don't drink a lot of water or use a lot when cooking, a portable RO system is a great option.

Reverse osmosis treatment systems are a great, affordable option for supplying clean, pure drinking water. If you have questions or need more information about reverse osmosis or other water treatment options, speak with your water professional at Skillings and Sons. They can help you to determine if an RO system is the right choice for your family!