Do you want to know how does reverse osmosis work because you’re planning to get one for your home? Yet, you know next to nothing regarding a typical RO unit, but you want to learn more.
There are many questions that you want to know like does reverse osmosis remove good minerals? Or, does reverse osmosis change the pH of water? Or maybe, do I need to add minerals to reverse osmosis water?
There are many more crucial details to learn about, like the RO system stages or an RO flow diagram. Or perhaps the RO water purifier features.
All of these details will be answered in good time. If you are a concerned homeowner that cares about the people that live in your home, you want to provide them the best drinking water there is.
There are many types of water filtering systems that you can choose for your home, but the reverse osmosis water system installation is the best one.
And to get the best drinkable water, you have to filter it out using a reverse osmosis unit.
And it provides one of the best water filtering solutions. In this specific process, a membrane that’s semi-permeable can remove ions, molecules, and larger particles in the H2O.
Reverse osmosis has many more positive attributes compared to the other types. It’s because it has five levels of filtration that get rid of damaging pollutants like lead and other heavy metals.
There aren’t many components in a typical home reverse osmosis system installation, and this way, it makes easier maintenance and cleaning. And it is EPA (Environmental Protection Agency) approved.
This type is cheaper than an ultraviolet disinfectant system and more efficient than a carbon or charcoal filtration process. It is best applied to water that’s previously chlorine treated.
However, it is sometimes ineffective, wherein it can use up to three gallons to yield one gallon of filtered H2O.
Table of Contents
What is osmosis?
If you want to learn everything about reverse osmosis, you have to know first what is osmosis.
It is the dispersal of dissolvent molecules through a semipermeable membrane. It goes from a less condensed solution to a more concentrated one.
It is a naturally happening process in nature, which relates to all living things. A great example is how human beings’ kidneys absorb water from their blood or whenever the roots from plants assimilate water from the soil.
Semipermeable membrane
A semipermeable membrane is a pliable sheet of material that admits some molecules or atoms to go through but not others. A great example to illustrate this is a metal screen door, which lets air get through but not bugs or anything bigger than its holes.
What is reverse osmosis?
It is a process to get rid of contaminants in the unfiltered water, which goes through a semi-permeable membrane. The water flows through a more concentrated membrane part that strains out more pollutants. Then go to a less condensed portion to produce purified water.
The leftover concentrated H2O is waste and called brine water. And the cleansed water is known as permeate.
The membrane has tiny pores that barricade the pollutants but provides access to water molecules. In the process of osmosis, H2O becomes concentrated as it goes through the membrane for both sides to gain balance.
With reverse osmosis, it blocks off the pollutants that pass through. Of which comes from the less concentrated portion of the membrane.
A great example of this would be when saltwater passes through the membrane. As pressure is imposed, the salt remains, and only the correctly cleansed H2O gets through.
How does reverse osmosis work?
The RO system works by getting rid of chlorine and sediments from the H2O via a pre-filter before it enables water to get to the membrane to take away dissolved solids.
After water comes out of the membrane, it worms its way through a post-filter to polish it before it comes out of the regulator or faucet. It can undergo many stages, which will be dependent on the number of pre and post-filters.
The reverse osmosis system utilizes a cross filtration instead of a standard one wherein the pollutants are amassed in the filter medium.
In the cross filtration process, the liquid crosses the filter within two outlets. The purified water goes one way, and the dirty water goes to another.
To prevent contaminant build-up, cross-flow filtration makes water possible to eliminate it. It also grants sufficient turbulence to enable the surface of the membrane to be clean.
Its different filters
- Sediment filters- This filter type filters out particles like rust, dirt, and dust.
- Carbon filters- It removes VOCs or volatile organic compounds, chlorine, and other pollutants. To makes the taste and smell of the water bad.
- Semi-permeable membrane- It gets rid of seventy to ninety-eight percent of TDS or total dissolved solids.
The different contaminants that are removed by RO
The RO process can remove up to ninety-nine percent of pollutants in the water like ions, pyrogens, colloids, particles, bacteria, and organics. Yet, it should not be dependent upon removing one-hundred percent of pollutants, viruses, and bacteria.
The semipermeable membrane also blocks any other contaminants based on the charge and size. Any impure material that has more than two hundred molecular weights will be cast away.
Also, if the contaminant has a higher ionic charge, the more reason it would not get through the membrane.
Great examples are sodium ion, which is monovalent or has only one charge. Also, a calcium element has two charges. And both aren’t cast away by the membrane.
Same thing with CO2 because it is ionized or charged highly and whose molecular weight is low.
Since the RO does not get rid of gases, the water will have a lower than usual pH level.
The RO process is also adept in the handling of surface, ground, or brackish water. It is for either small or large quantities. Some industries that utilize RO treated water are semiconductor manufacturing, pharmaceuticals, food and beverages, metal finishing, and many more.
Where to install it
The best location to set it up in a typical home is the kitchen sink. However, some households have a smaller kitchen and don’t have large enough space to accommodate it.
Another area that you can set it up is the garage, basement, or utility room. If you opt to use those spaces, then you need a delivery pump.
The vital thing to remember is that you have to set it up in a cold water line below any other filtering device that you will use in conjunction with the RO, like a softening system.
Lastly, never install it in areas that have freezing temperatures.
Components of RO water purifier
Cold water line valve
It is the valve type that attaches to the cold water line. It has tubing that fastens to the pre-filters inlet portion. It is where you get the whole source of water from the reverse osmosis system.
RO membrane
It the central mechanism that the whole unit depends on and is regarded as the heart of the system. It is made to get rid of many harmful contaminants and other particles in the water.
As the water gets through, it flows towards the pressurized tank, where the filtered water is stored.
Pre-filter
Water coming from the cold water line goes to the pre-filter first, and there might be more than one in a typical unit. The most prevalent kinds of filters are carbon and sediment.
These are utilized for the membrane’s protection by getting rid of dirt, silt sand, and other sedimentary substances that might congest the system. Also, carbon filters can get rid of chlorine in the water, which can impair the membrane.
Post filter
After the purified water gets out of the tank, it goes through the post-filter, which is the final filtering process before it comes out of the RO spigot.
It is usually a carbon filter, which takes out any remaining smells and tastes and is polished before it is drinkable.
Storage tank
The standard tank for storage of purified water can store two to four gallons. There is a bladder mechanism within it that maintains water pressure whenever it is replete.
The size of an under-the-sink tank is fifteen inches tall and twelve inches in diameter.
SOV or automatic shut off valve
The SOV is a mechanism used to save water for the unit. Whenever the tank is filled to the brim, it automatically turns off and blocks any more water to get through the membrane and stops the water from flowing to the drain.
If you turn the spigot knob to draw water, the pressure drops in the tank. And the valve opens to let the water flow through the membrane and the pollutants. Along with other impurities is sent to drain.
Check valve
It is situated near the housing of the membrane, at the end of the outlet. Its chief function is to keep the backward current of filtered water from arising from the tank. It can also possibly burst open the membrane.
Flow restrictor
Its function is to regulate the water current that goes through the membrane. There are varying styles of this mechanism but have the same purpose of maintaining the required rate of the flow to get the best quality of water.
Its other function is for pressure regulation on the membrane’s inlet portion. Without the pressure enforced by the flow restrictor, only little drinkable water is supplied. It’s because the incoming water would flow through a pathway of the least amount of opposition, which is the route going to the drain.
In most models, it is situated near the tubing of the drain line.
Drain line
Its whole connectivity starts from the membrane housing’s end of the outlet and goes to the drain. Its chief function is to discard the pollutants and waste from the water that was filtered out by the membrane.
Faucet
This mechanism is mounted atop the kitchen sink, where filtered water is drawn from. There are specially-designed faucets that you can purchase and screw into your sink to complement your kitchen’s interior design.
Some places have regulations that the homeowners have to install an air gap spigot, yet non-air gap types are more prevalent.
How to install a reverse osmosis system
You should learn how to make an RO system at home, specifically under the sink, since it is the location where families usually draw water to drink and cook. There also other RO systems that you can set up for the whole house, but the under-the-sink unit is easier and typical in most households.
This particular unit has four or five canisters that filters out water and each has a task in filtering specific kind of contaminants. Then it has a storage tank that contains the purified H2O.
There is also a spigot that pours out the filtered water that is separate from the kitchen faucet.
Even though the science of the RO water system installation diagram might look complex, the reverse osmosis installation instructions are reasonably straightforward. If you are adequate plumbing skills, then you can set it up yourself.
Step one: Planning the installation
It is still the planning stage, so at this point, you haven’t bought an RO system yet and want to get one. You have to check if there is enough room below the kitchen sink to fit the filters and tank.
You have to measure that is because your sink may already have other stuff attached like a garbage disposer that might make the filters difficult to fit.
You also have to be aware of how your home’s source of cold water can be utilized. It is because some RO units can attach themselves to the water line going towards the faucet. The device used for this is called a tee connection.
Other RO systems utilize elastic tubing that comes directly from the faucet. Wherein the adapter tee right above the shut-off valve is used to draw water for the filtering system.
Step two: Preparing the reverse osmosis unit
At this stage, you have found out that there’s enough space under your kitchen sink, which you can attach to the RO system. Let it out of the box and check again if it fits on the spot you’ve pre-selected.
Do it with all the unit’s attachments and components. This way, you will be aware if it would be necessary to make adjustments on the drain or water pipelines. If that is the case, then you will need help from a plumber.
Many RO units are designed for under-the-sink installations, but they can also be set up in another place in your house, like a garage or workshop. And then have a connection towards the sink’s location.
The filtering system has to be attached along the cold water pipeline. And if you have a water softener pre-attached, be sure it is past that.
Installing it in another location aside from the kitchen sink will not take up space below it. However, more work is necessary since it necessitates extra tubing to attach the components to the unit.
Step three: Attaching the spigot
The sink faucet is the first component that needs to be attached because if you do it last, its tubes may not be able to fit and get crowded underneath the sink.
Attach the spigot to the sink countertop. There should be accessories provided along with the kit.
Your sink may have an existing orifice to accommodate the spigot and is for a sink sprayer. If not, then you need to bore a hole on the countertop to be able to fasten the faucet.
Insert the water line going down through the orifice and fasten it to the air gap and into the kitchen faucet. It has to be done before fastening it permanently to the housing.
Step four: Positioning the tank
At this stage of the connection process, you will be placing the RO tank below the kitchen sink. Before doing it, set up the tank connector first.
Get the plumber’s seal tape and apply it along the threads on the nipple of the tank. Then fasten the spigot connector on the tank and be sure they aren’t cross-threaded.
The connector should be threaded on easily as could be, and be sure to attach it securely.
Step five: Mounting the filter and its accessories
Take out the cover from the filter assembly and indicate it on the wall underneath the sink for the hanger washers. The measurements of the assembly have to be fifteen and a half inches more or less from the flooring. It enables enough space to take out the filters for maintenance purposes.
Fasten the hanger washer on the wall at the indicated spot. Then proceed to install the RO unit assembly onto the washers.
Step six: Attach the water line
You will see a lean water line from the assembly, measuring one-fourth inch and usually green in color. You need to attach it to the water supply line. Before doing it, shut off the water supply first.
If the sink utilizes a one-half-inch flex line, so your one-half-inch adapter will work fine with it. However, if the sink uses different-sized tubes, then you will need an adapter tee to enable the changeover to the water supply line going to the filter unit.
The green water line is fastened to the adapter tee using an insert, nut, and ferrule.
Step seven: Attaching the other tubing
The configuration of the tubes may have different sizes due to their manufacturers.
They comprise one piece tubing from the main supply going to the filter unit’s first canister. It is known as the pre-filter.
Another one coming from the last canister filter. Which is known as the RO canister, going to the drain. And another tubing going to the storage tank.
The last tube will run from the storage tank going to the countertop towards the faucet. The pro series 5 stage reverse osmosis system installation instructions state that the storage tank has to go through a filter that polishes the H2O right before going to the spigot on the countertop.
Since the configurations of the tubes might differ due to the manufacturer, you should always confer with its user’s manual to know to correct connections for the tubings.
For tubing connections, the longer ones are more advantageous. Since you can position them behind furniture or anywhere necessary to get a cleaner installation. And be sure to leave it on a considerable length behind if you need to transfer it again later.
You can also cut it to the correct measurements to get a more concise appearance. Also, follow the instructions from the manual to sanitize the whole system first before attaching the tubes.
Step eight: Connecting to the drain
There is a type called a whirlpool RO system, which includes a drain tee. Put it against the drain pipe and make a marking so that you’ll know where to cut the piping.
Use a hacksaw to cut the pipe and be sure the tee can fit securely. Then attach the drain tee’s filter to cut the piping along with the nuts and washers. It follows the same assembling procedure as the drain trap. Lastly, push the drain tube of the filter in the adapter tee.
Step nine: Make a pressure test
It is the last stage in learning, how does a reverse osmosis unit work, wherein you will need to do a test.
Switch on the main supply line, thus opening the cold water on the kitchen sink. It will forcefully let the air out from the pipes. The pressure will begin to develop in the system.
You will need to wait for two hours to get the full brunt of the pressure.
After reaching full pressure in the system, get back to the attachments. And look for any loose connections, and tighten them if you find one.
Before utilizing it for drinking purposes, drain out the system by switching on the spigot. It will purge the system entirely and leave it that way for twenty-four hours.
The water will slowly trickle after the tank is emptied. At this stage, continue to check for leaks.
Some dangers of RO water
WHO said that drinking RO water has bad side effects
Based on some scientific studies made by WHO (World Health Organization), it was discovered that constantly drinking water that has been treated by reverse osmosis process can result in impairment to the human body. It is even more harmful than ingesting the contaminants that it is supposed to save people from drinking.
Most home-based units prefer and utilize RO systems as a treatment for their tap. Even many water purifying companies use it as their means of purification of their bottled H2O merchandising.
A typical RO system does remove pollutants and impurities in the water, but it also gets rid of essential elements in the body like magnesium and calcium, about ninety-two to ninety-nine percent of them.
After a slew of research and testing by WHO, it was viewed that RO water is bearing damaging effects on people and animals if consumed for even a few months.
Some places in Slovakia and the Czech Republic used RO systems for their public water. Its citizens had acquired calcium and magnesium deficiencies, which resulted in many health issues.
Some of the bodily issues were muscular cramps, cardiovascular ailments, constant weakness, and tiredness.
Ro water lack essential minerals
Whenever people ingest RO water, it has a way of removing minerals from the body. It means that if you have taken life-affirming minerals from vitamin pills and food, drinking RO-treated water will strip those from your body and urinate them away.
This daily ingestion procedure of drinking RO water and mineral extraction from the body will result in bodily ill effects.
In another scientific research to find out if the essential mineral taken in the body can compensate for the deficient minerals in the RO water, it was discovered that it wasn’t evened out from the diet.
Its almost nonexistent mineral content was the chief cause why minerals were excreted from the body.
It affects negatively on the body’s metabolic equilibrium or homeostasis
Constant ingestion of RO-treated water can result in the weakening of the dissolved electrolytes in the human body. And if the water distribution to the different portions of the body is sorely lacking. It will negatively affect the operation of the vital organs of the body.
From the start of this condition, the body will experience general weakness. And also tiredness and constant headaches. Some of its worse indications are diminished heart rate and muscle cramps.
Risk factors
Another scientific study was also done about RO water wherein it was discovered that constant ingestion of it is a factor that leads to many diseases. Similar to duodenal and gastric ulcers, coronary heart disease, hypertension, goiter, gastritis, and pregnancy issues.
It also results in an array of difficulties in newly-born babies like anemia, growing issues, skeletal fractures, and jaundice.
Not ideal for cooking
It was also discovered that if RO water is included in cooking, it removes all essential nutrients in the food, like cereal, vegetables, and meat dishes.
The vital substances removed are as follows:
- Magnesium- Sixty percent is lost
- Calcium- Also sixty percent
- Manganese- Seventy percent
- Copper- Sixty-six percent
- Cobalt- Eighty-six percent
If mineralized water is utilized instead of RO water, calcium content increases and the loss of the other elements is lower.
Adding minerals back to RO water
WHO also reported that the usual method of operation when minerals are returned to RO water does not have a favorable result. It is because the water does not have the nutritional elements already.
In the situation of RO water, it is inconceivable to remake natural water that has all the correct elements and mineral levels.
The proper levels of elements (minimum and optimum) that has to be exhibited in water are as follows:
- Magnesium- Ten mg/L (minimum), twenty to thirty mg/L (optimum)
- Calcium- Twenty mg/L (minimum), fifty mg/L (optimum)
- Overall hardness of water- Total sum of magnesium plus calcium should be equals to two to four mmol/L
Despite the supposed ill-effects mentioned about RO treated water, it also squanders seventy to eighty percent of water during the purification procedure. The wastewater is saline-based and has too many pollutants, thus rendering it unusable.
Other options instead of RO water
- Boil it- Try to boil the water instead, and make sure to do it properly. Once it is boiled, let it steam out for a few minutes.
Yet, boiling does not remove the chemical-based pollutants in the water. Also, it won’t be applicable without a fire source or working electricity. - Add chlorine- Put in four droplets of bleach in one liter, or eight droplets in one-half gallon, or sixteen droplets in one gallon.
Leave it on its own for more than thirty minutes to make it safe for drinking. However, too much chlorine is harmful to the inner vital organs and must be dealt with carefulness. - Include iodine- Add five drops of iodine in one liter and some more if it’s brackish. Leave it be for more than thirty minutes to do its magic.
Iodine drops work better if the temperature in the water is about twenty degrees Celsius or more. Yet, it does not eliminate all the pathogens and other contaminants in the water.
The role of the government and the medical profession
If the public tap water in a particular location fails and unable to provide drinkable water to its citizens, the government should look for measures to repair the issue. Safe drinking water for the masses is one of their responsibilities and should be given utmost priority.
The medical profession in the locality should educate the citizens about the supposed problems with RO water and teach them the correct options.
Truths and untruths of RO water
Facts
Based on scientific research, an adult man needs to drink thirteen cups or three liters of water per day. And an adult woman should ingest nine cups or 2.2 liters.
For people to stay in perfect health and excellent bodily conditions, the proper water they should consume should have minerals that contribute more sustenance to their health. The kind that has potassium, magnesium, and calcium, which are inorganic materials established on planet Earth.
There are problems in regards to water that everyone on the whole Earth is affected. Ninety percent of all known illnesses concerning water and give rise to eighty percent of all demise in developing countries. The total number of water drinkers caused to be annihilated by this adds up to more than five million per year.
They mostly come from acute sicknesses due to contaminants like bacteria, viruses, etc. These are inclined to have greater value than the supposed consequences of consuming unclean H2O.
Chemicals like fluoride, arsenic, nitrate, lead, etc., are some of the elements that should be areas of concern. These usually come from specific human behavior of working. Good examples are mining, manufacturing, and farming, which are often neglected as the origin of these illnesses.
All of these are aggravated by troubles resulting from potable water shortages. And as the population of Earth becomes greater, the determined amount of drinkable water becomes polluted, and the people have no choice but to drink it.
These perceived issues can be repaired by purifying the water and is successful in killing and controlling deadly pathogens. So in time, water purification methods were established, which included the RO procedure.
It was regarded as an excellent method of terminating the pollutants like microorganisms, salts, organics, and suspended solids and is successful in doing this.
However, most people are not aware that this process also strips it of the naturally occurring minerals in the water that the human body needs. As mentioned earlier, it gets rid of ninety-two to ninety-nine percent of magnesium and calcium, which are beneficial to people’s health.
These are alarming facts, and drinking RO-treated water for a few months can have dire effects on the body.
Myths
There is an untrue claim statement that people think is real wherein the purity of RO water assaults the body’s mucous membranes and results in adverse effects.
It’s known to have low TDS or total dissolved solids (it refers to the overall amount of concentrated salts in water, which is measured by mg/L).
However, there are pieces of evidence that low TDS in water brings no health benefits to the drinkers. And no proposals were conducted yet about health guidelines for TDS. It is because the problem wasn’t considered too dire to merit it.
Another untruth is that other water treatment processes are as ineffectual as the RO procedure. There are other methods like CDI, natural zeolites, and many more. These proved to be effective for water treatment and can replace the former.
Another untrue statement is that the RO procedure is inefficient and wastes a lot of water. And also, the membranes needed to be constantly replaced.
All water treatment methods get rid of contaminants by separating unclean for clean water. The pollutants are replaced then absorbed by activated carbon and ion exchange resins and have to be removed.
With RO treatment, the unaccepted wastewater goes to a separate continuous current. The wastewater is not concentrated and is only thirty-three percent more than the purified water.
Also, it was found out that membranes utilized in the RO system can last as long as ten years.
Another myth is that bottled H2O is more beneficial than RO treated water. And in truth, many people have come to rely on it for their only potable water source.
This thinking has arisen from the evident lack of assurance from their municipal or city water supplier or privately-owned well-water. And in some ways, there are truths in the statement.
All United States municipalities and cities must adhere to EPA’s (Environmental Protection Agency) requirements in their Safe Drinking Water Act. Yet, some systems of water distribution, like the public pipelines can deteriorate, and harmful chemicals will seep through. It will harshly affect it before it arrives in lots of homes.
All types of waters on the planet have pharmaceutical and personal care products, also known as PPCPs. These are minuscule amounts of organic matter that come from human actions.
These are regarded as pollutants that get absorbed into the H2O. And it is approximated that there are 85k assorted chemicals in it.
The RO process does improve the drinkability, yet not all bottled types are derived from the RO method. Some are from the municipal, city, and even spring water.
These may have undergone ozonation to get rid of the impurities, but you can’t tell what water treatment method is employed. Unless it was stated in its labels.
Also, since the bottles are made of plastic, there are concerns that their chemical content will seep through the water and contaminate it.
Another is the costing and promotion of the H2O. Some of its companies falsely claim that their water provides more sustenance than others.
They also jack up the prices as the result, and some can be as expensive as nine dollars per gallon. And this purported miracle water ends up being more costly than gasoline.
As a result, many American citizens spend about twelve billion dollars per year on bottled water types.
The plastic bottles, once disposed of, causing damage to the environment due to their chemical components. There is a statistic that Americans throw away about sixty million water bottles in one day.
Although nine percent of it gets recycled, the majority goes to the city dump. It is estimated that breaking down plastic products takes four hundred fifty years. It will proceed to go to the ocean and remain there.
And in the future in the year 2050, there is a prediction that the total weight of plastic products will surpass all of the marine creatures’ weights.
Conclusion
There is a lot of controversy about the RO treatment process, whether it is beneficial for you or not. However, all food and drink are bad for you if consumed too much. So, moderation is key, and this also goes for all RO water drinkers of the world.
