Reverse Osmosis

What Is Reverse Osmosis?

Reverse osmosis is a technology used to filter water by pushing it through a semipermeable membrane under high pressure. This process removes most contaminants from the water & produces clean, fresh drinking water.

This page is for readers with little or no experience with reverse osmosis. We will explain the basics in simple terms that should give you a better overall understanding of reverse osmosis water technology & its applications

This article covers the following topics:

  1. Understanding The Basics Of Reverse Osmosis
  2. Osmosis
  3. Semipermeable Membrane – What’s That?
  4. A Better Understanding Of Reverse Osmosis
  5. How Does Reverse Osmosis Work?

 

Understanding The Basics Of Reverse Osmosis

Reverse osmosis as a technology & device is & has been a popular topic in the water treatment industry for decades. It’s no wonder people are interested in learning more about reverse osmosis systems, given that they have some of the lowest energy requirements & highest recovery rates on the market.

Today, we will explore the heart of a RO system and break it down so that you have a thorough understanding of RO systems.

To understand the basics, purpose & process of the reverse osmosis & RO System, you must first understand the naturally occurring process of Osmosis.

Osmosis

Osmosis is the scientific word for a naturally occurring process where weaker salt solutions travel to areas of stronger salt concentration.

  • Some examples of osmosis are the absorption of water from the soil by plant roots and the absorption of water from the blood by our kidneys.

 

The diagram adjacent demonstrates how osmosis works. A solution with a lower concentration will naturally flow into one with a higher concentration.

For example, if you had two containers of water with different salt concentrations – one high and one low – and separated by a semipermeable membrane, the water with the lower salt concentration would begin to move towards the container of higher concentrated salt water.

Semipermeable Membrane - What’s That?

A semipermeable membrane is a selective barrier. It only allows certain particles to pass through while keeping others out. For example, a screen door keeps bugs and other tiny pests from entering your home while allowing fresh air to circulate.

Let's Get A Better Understanding Of Reverse Osmosis!

The process of reverse osmosis is the act of reversing osmosis. Usually, osmosis would occur without any energy needed; however, to invert the process, you must apply energy to the more saline solution.

A reverse osmosis membrane is a material that only lets water molecules pass through but not other things like salt, bacteria, and virus particles. To get pure water from this process, pressure must be applied stronger than the natural force pushing the contaminated water against the membrane.

Below is a diagram to explain “How does Reverse Osmosis Work?” outlining the process of reverse osmosis. By exerting pressure on the concentrated solution, pure water molecules are forced through the semipermeable membrane while contaminants are blocked.

How Does Reverse Osmosis Work?

Reverse osmosis is a process that uses a high-pressure pump to force water across a semipermeable membrane, leaving almost all (around 95% to 99%) of the dissolved salts behind. This allows for incredibly pure water on the other side of the membrane.

The pressure needed to pump the water through RO membranes is based on how much salt is in the feed water. The higher the salt concentration, the more pressure is required to reverse osmosis (a by-product of increased dissolved minerals in solution).

The water that has been demineralized or deionized is called permeate (or product) water. The stream of water that contains contaminants too large to pass through the RO membrane is called the reject (or concentrate) stream.

As the feed water enters the RO membrane pressurized (enough pressure to overcome osmotic pressure), the semipermeable membrane lets water molecules pass through it.

The salts and other contaminants are discharged through the reject stream instead of being allowed to pass. The reject stream goes to the drain or can be fed back into the feed water supply in some circumstances so that it is recycled through the RO system, which saves water.

After the water passes through the RO membrane, it is referred to as permeate or product water. This type of water usually removes 95% to 99% of dissolved salts.

Understanding that a reverse osmosis system utilizes cross-filtration rather than standard filtration, where the pollutants are collected within the filter media. With cross-filtration, the solution passes through the filter in two outlets, and the filtered water goes one way while the contaminated water goes another.

To sidestep the buildup of pollutants, cross-flow filtration permits water to clean away contaminant buildup & also allows sufficient turbulence to maintain the membrane surface unsoiled.

Reverse Osmosis System Installation & Repair

4 Stage Reverse Osmosis System Installation Starting at only $495.00.

Are you looking for an under-sink reverse osmosis system? Whether you need help with replacement filters or filter changes, we have licensed plumbers to help. Even if you didn’t purchase your system through us, we still service it if it needs repairs or replacement parts.

We can supply your RO system with a faucet that will match your existing fixtures. Please contact our office for pricing and selection. There are popular options: brushed nickel, black, copper, white, and more!

NRO4-50 & NRO5-50

4-Stage and 5-Stage 50 gpd RO Systems featuring double o-ring housings and a clear pre-filter housing for a quick inspection of the sediment filter. Also features a 3.2-gallon NSF-approved storage tank.

This system utilizes 1/4″ compression fittings, 1/4″ tubing, and a chrome long-reach, lead-free faucet. Also includes a filter wrench.

TWIST-LOC-RO-75

4-Stage 75 gpd NRO Quick Change Twist & Loc RO System features a quick-change twist & lock cartridges. The Quick Change Twist & Loc cartridge is disengaged and removed with only a quarter twist of the wrist without shutting off the water. Cartridges can even be changed when the customer’s home water system operates under full pressure.

The system also features 3/8″ delivery from the holding tank to the faucet, quick connect fittings on RO for easy installation, an angle stop adapter valve with quick connect fitting, 3.2-gallon polypropylene coated NSF-approved white steel tank and installation hardware, filter wrench, and a chrome lead-free faucet.

The Quick Change Twist & Loc 75 gpd RO offers optimal levels of water filtration to reduce dissolved minerals, bad taste, and odors.

****Well water packages address hardness, iron, taste, and odor issues. Pricing will vary based on the conditions that need to be addressed. We are happy to come by and assess your water conditions and recommend the appropriate equipment based on your needs and budget. You can also visit our pricing page here.

Replacement Filters & Accessories

FlowLok Leak Detection Kit

FLOWLOK Leak Detectors utilize a highly compressed safety disc that expands when it absorbs water. Once the safety disc has detected water, it develops and trips the FLOWLOK safety lever to shut off the water entering the water filtration device.

The FLOWLOK Safety Tray is a specially designed tray to contain any leaks from the water filtration system. Its slightly oversized length helps capture any drips or leaks originating from connectors in the inlet and outlet of the filtration device. Includes two Safety Discs.

NRO Filter Replacement Packs

Drilling

If it’s required to drill a hole in your countertop for the RO faucet, there will be a $75 additional charge.

We serve all areas of central Texas, including Austin, San Antonio, Dripping Springs, Blanco, Wimberley, San Marcos, Buda, Kyle, Lakeway, New Braunfels, Helotes, Pflugerville, Boerne, and more! Contact Us today to schedule your service.

FAQs About Reverse Osmosis Systems For Your Home

Most people have a reverse osmosis unit installed under their kitchen sink. If that’s not an option, the system can also be placed in a basement, closet, or utility room. Because a RO unit comes with its own dispensing faucet, a hole may need to be added to your sink or countertop for installation. However, some sinks are already built with extra space for mounting.
Only pre and post-filters must be replaced annually to ensure excellent performance. Eventually, the quality and the amount of water usage will decide how often you need to change your filters. Depending on the point-of-use RO model, the annual cost is less than $0.30 per day. The RO membrane itself will typically last between two & five years.
No, in fact, a water softener can help in extending the life of the RO membrane. Magnesium and calcium are two of the hardest minerals for the RO membrane to eliminate. Sodium is much lighter or more manageable as it removes 98% of all sodium in the water.
While both RO units and distillers effectively reduce water’s “dissolved solids” content, the processes are pretty different. The RO system filters water through a really tight semipermeable membrane. On the other hand, a distiller is like a vast teakettle. It boils water, catches the steam, condenses it, and captures the water produced. Most contaminants are left as a residue in the boiling cell. Both rely massively on carbon filtration for the removal of chemicals. Cheap distillers often have limited or no carbon filtration and are ineffective.
Water, in its purest form, has no flavor or odor. When you “taste” water, you actually taste what’s been dissolved in it. People have different opinions on what causes water to taste good. If you hate the smell or taste of the water in your home, you will most likely favor RO water. Many households find they started drinking more water after installing an RO system.

Most people have a reverse osmosis unit installed under their kitchen sink. If that’s not an option, the system can also be placed in a basement, closet, or utility room.

Because a RO unit comes with its own dispensing faucet, a hole may need to be added to your sink or countertop for installation. However, some sinks are already built with extra space for mounting.

Only pre and post-filters are needed to be replaced every year to ensure prime performance. Eventually, the quality and the amount of water usage will decide how often you need to change your filters.

Depending on the point-of-use RO model, the annual cost is less than $0.30 per day. The RO membrane itself will typically last between two & five years.

No, in fact, a water softener can help in extending the life of the RO membrane. Magnesium and calcium are two of the hardest minerals for the RO membrane to eliminate and sodium is much lighter or more manageable as it removes 98% of all sodium present in the water.

Yes, you can but believe us, it will be difficult. Let a residential water treatment professional like Lone Star Water Services attach everything to the correct spots.

A local professional at Lone Star Water Services will examine factors such as your home’s water temperature, pressure, overall water quality, and the distance of the holding tank to the faucet. This information is also essential for understanding your unit’s maintenance needs.

If you still have queries regarding the installation of a RO system at your home, feel free to contact Lone Star Water Services’ local water treatment expert.

We have qualified professionals with an in-depth knowledge of equipment and the craftsmanship behind treating residential water. They will conduct a free water report at your property, examine installation areas and give you the advice you need.

How Much Does A RO System Cost?

The cost of a reverse osmosis system at Lone Star Water Services varies depending on the size of the unit & the features that are included. For more information regarding the prices, please fill the form – and we will back to you in no time.