Reverse Osmosis Water Treatment
Reverse Osmosis Water Treatment uses a semi-permeable membrane to remove a variety of contaminants from drinking water. It follows a natural process called osmosis, which is found throughout nature (plants use osmosis to absorb water and nutrients from soil).
A quality RO system includes a sediment filter and carbon filter. Changing these filters regularly keeps the membrane from clogging.
What Is Reverse Osmosis?
The basic process of reverse osmosis involves pushing water through a semi-permeable membrane. The membrane allows water molecules to pass, but keeps other contaminants on the pressurized side of the membrane. This leaves the more concentrated solute on one side and pure solvent on the other.
This process is used in the food industry as well, with maple syrup producers using reverse osmosis to separate out the sugary concentrate from the water in their sap. The process is also used in the dairy industry to create high quality whey and milk products, and in wine production for pure ethanol.
Reverse Osmosis is a great option for those that are concerned with what’s in their drinking water. Most municipal water is clean when it leaves the treatment plant, but over the course of its travels through pipes to your house it could pick up a variety of contaminants. In addition, private well water can contain harmful bacteria and a higher than normal amount of total dissolved solids (TDS). Reverse Osmosis is able to remove most common pollutants including nitrates, lead, sulfates, fluoride, bacteria, pharmaceuticals and arsenic.
Many of these contaminants can be very dangerous if taken in large quantities. The EPA regulates contaminant levels, but it can take years for new standards to be established. For this reason, many people choose to install an RO system to ensure they are always drinking the highest quality water possible.
While a reverse osmosis system does eliminate many toxins from drinking water, it does remove beneficial minerals as well. It is important to remember that our bodies are 70-80% water, and it is the food we eat that provides us with our essential minerals. For this reason, many choose to install a four-stage RO system with a carbon filter, which will re-mineralize the water and add back vital nutrients that are removed by the RO membrane.
How Does Reverse Osmosis Work?
A reverse osmosis system uses a semi-permeable membrane to separate water from contaminants. The membrane has holes, or pores, that are just large enough to let water molecules through but too small for the vast majority of contaminant particles. This is similar to the way a furnace air filter works, but reverse osmosis takes it a step further. Reverse Osmosis Water Treatment The membrane also allows dissolved salts through, but almost all other contaminants are removed with it.
The membrane is separated by a concentration gradient that naturally forces solvent to move from the side where it has a higher concentration to the side with a lower concentration. When the pressure applied on the solution side of the membrane is greater than osmotic pressure, the molecules of the solute start moving to the pure water side of the membrane. This is called osmosis.
Most systems start with a prefiltration stage that includes carbon and sediment Filling Machine Supplier filters to remove chlorine and other contaminants that could clog or damage the membranes later in the process. Then the water moves through an RO membrane where all dissolved chemicals and contaminants, including ions, are removed from the water, leaving great-tasting, clean water behind.
The pure water then drains into a storage tank. Before it is dispensed, the water will usually pass through another set of filters that remove any residual tastes and odors that may be trapped in the storage tank walls or bladder. It will also be run through a UV light to kill any bacteria that may have survived the other filtration stages. This water is then ready to drink, cook with and use in your home’s appliances. Nutritionists recommend that you drink half your body weight in ounces of water each day, so a reverse osmosis system can help make sure you are getting enough water to keep you healthy and hydrated.
Advantages of Reverse Osmosis
Reverse osmosis is one of the most effective water filtering methods available. It filters down to the molecular level, removing contaminants and sediments like chlorine, salt, and dirt from drinking water. The process also removes harmful microorganisms that may be in the water, including bacteria and viruses.
It uses a high amount of pressure to push water through the semi-permeable membrane. Depending on the specific system, this pressure can be as much as 200 to 376 pounds-per-square-inch (psi). This is about 6x the average water pressure in suburban American homes.
This intense pressure allows reverse osmosis to separate pure water from impurities. Typically, the process consists of four stages: a sediment filter to remove large particles like dirt and rust; a pre-carbon filter to prevent clogging by binding with positively charged ions; the reverse osmosis membrane to separate water from dissolved salts, organics, and bacteria; and a post-carbon filter to polish the water. The result is water that is almost as clean and fresh as bottled drinking water.
The filtration process can also remove disinfection byproducts that are created when chlorine or chloramine react with natural organic matter in the water. These byproducts can cause digestive issues and have been linked to higher cancer risk. In addition, the system can remove PFOA and PFAS, chemicals that leach from common household products into the water supply when they’re heated.
Another advantage of reverse osmosis is that it produces clean, filtered water instantly. The resulting water is stored in a storage tank until needed, which can reduce the amount of plastic bottles used in the home. Some systems can even add a permeate pump to the system to minimize the amount of water that goes down the drain, reducing the waste and saving even more money.
