If you are dealing with salty water, then “yes,” either one of the residential reverse osmosis systems, or a distillation system, is needed. But, if like most of us, you get your water from a chlorinated system with no salt problems, you have simpler and far less expensive options. We will cover one these options in this article called selective filtration.
The increase of chemical toxins in our environment has led to a lot of discussion about our “body burden”, the term for the total amount of these toxins in our bodies at any given time.
In the past, we worried a lot about the quality of the water we consumed and how it was affecting our bodies, and rightly so, but now scientists are discovering the quality of the air in our home poses an even greater load on our bodies. One of the largest offenders is chloroform, a byproduct of the chlorine in our water.
“Every home in America has an elevated level of chloroform gas due to the vaporization of chlorine…from the tap and shower water,” according to the EPA. (It’s true, the shower is the largest producer but the dishwasher and the washing machine aren’t far behind).
Since whole house units remove chlorine and other toxins from the water, at the point of entry into your home, they greatly improve both the air quality and the water quality.
And, there is a compelling reason to look at RO and SF technologies before you buy, because they differ significantly in initial costs and the cost to operate.
Since quality residential reverse osmosis systems start around $10,000, compared to a quality residential selective filtration systems at about $800, the $9,200 spread can mean the difference between getting a whole house unit or not.
Why the big difference in price?
One of the hardest things to remove from water is salt and, years ago, RO was developed as a cheaper way to clean up salt water than by using distillation. But that was when water and electricity were both very cheap. Today RO is an expensive technology as you will see.
Water is forced through a membrane, in the RO process, that will only allow molecules equal in size or smaller than water’s to pass through. All other matter is left behind.
Not all contaminants are stopped by the membrane. Chlorine, its byproducts and many other chemical compounds have small molecules that allow them to pass through easily. Carbon filters are added to remove them and to protect the membrane.
The small RO systems are very slow, taking two or three hours to produce a single gallon of filtered water. Whole house units, on the other hand, can filter upwards of 2,000 gallons per day. Large or small units require a pressurized tank in order to be able to deliver a larger quantity water quickly.
The minimum pressure required to operate most of the smaller countertop units is 40 psi (pounds per square inch) and older homes, or some well water systems, may need to add booster pumps. Since more pressure is required to operate the whole house systems, booster pumps are usually included with the unit.
A lot of water is wasted, even with adequate pressure in the system, because for every gallon filtered, often 2 to 5 gallons of water cannot be pushed through the membrane. This water is then flushed, along with the filtered contaminants.
There are some systems that do recycle this water but, recycling, electricity requirements, storage tanks and, possibly, extra pumps are what cause the high initial costs and some of the higher operating costs. Then too, the more things in a system that can go wrong, the more chances there are for additional maintenance issues to further increase the operating costs.
About 95 percent of us are on a chlorinated water system, and that means a good option to consider is selective filtration.
In these systems, redox (reduction/oxidation), mechanical filtration and activated charcoal are integrated into a multistage filtering process that will quickly process the water at the whole house level.
Toxic metals dissolved in the water, such as lead or mercury, are removed by a chemical exchange process using a redox filter in a simple filtration technique. Until the recent development of redox filters, only RO or distillation could remove dissolved lead and other toxic metals from water.
Over 99 percent of the chlorine, chlorine byproducts and other organic chemicals are removed by the adsorptive power of the activated charcoal. The overall process of selective filtration removes bad tastes, odors and sediment from the water and acts somewhat like a water softener, but there is no unhealthy sodium added to the water.
All of this is done quickly, producing up to seven gallons of filtered water per minute, and install easily, without electricity, booster pumps or storage tanks.
For anyone wanting to improve the air and water quality in their home, selective filtration systems are a viable cost saving option to consider.