Purification of hard water
Water hardness is it's characteristic due to the presence of salts in the complex (mainly magnesium and calcium salts). It is measured in milligram-equivalent per liter (mg-eqv/l). The higher the water hardness, the less technical means that use it (washing machine, heating radiators, boilers, columns, dishwasher).
Hard water is not only bitter, which is already unpleasant, it also reduces the stomach motor, provokes failures in the digestive system. Salts of hardness, accumulating, lead to diseases of the joints, settle plaque on the skin and hair. Gallstone disease and kidney stones are also the result of long regular use of hard water.
How can you tell how much hard water is pumped from a well into a private home or from a well into a country water supply system? The most reliable way is to take a sample and test the liquid in the laboratory. But that's time, effort, money. There is a simpler solution: hard water has its "symptoms". Among them:
- raiding a tap;
- rapid scale build-up in the kettle or on the walls of pots where water boils;
- excessively fast detergent consumption (they do not foam well in hard water);
- white divorces on laundry after washing;
- the skin becomes dry after washing with hard water, a tight feeling appears.
In general, if there is a well on the site that supplies a resource from great depths, the listed "symptoms" can not even be found. Here, hard water must be treated in an orderly manner, as it is always saturated with salts in the ground. However, the softening system itself, which is suitable for a particular house and its water supply, may vary.
Softening methods for hard water
Today the market offers systems of chemical, physical, mechanical or combined hard water treatment. The first group includes:
- Reagent plants. This method uses so-called coagulants that bind magnesium and calcium salts into insoluble compounds. The latter precipitate on the walls and bottoms of the filter and the liquid purified from them enters the water system. The filters differ depending on the reagents used (sodium hydroxide, soda ash, phosphonates). Reagent treatment works well as prevention of boiler equipment breakage, but it is not effective for softening drinking hard water. The installation of additional filters is required.
- The ion-exchange method of hard water treatment uses filters with backfill of ion-exchange This method is based on the exchange reaction, as a result of which calcium and magnesium are converted into resin and the flow is saturated with sodium ions. Unlike salts, it is useful for human health. Such filters do not precipitate, so they do not need to be cleaned, which reduces the user's costs. Plus, the ion exchange resin is able to recover from washing in a solution of ordinary table salt (it is sold in a convenient tablet form). The ion exchange resin filter is suitable for household appliances and drinking water softening.
- The polyphosphate method uses sodium polyphosphates, which also react with hardness salts to form a film settling at the bottom of the unit. Water saturated with sodium salts is suitable for domestic purposes.
Physical cleaning methods are based on the creation of an electromagnetic field. These units are mounted directly on the water supply system. The result is similar to the reagent models: magnesium and calcium salts also pass into insoluble form - sludge, which is discharged through the sewage system. This filter is not suitable for drinking water but works as an excellent scale prevention in heating systems, dishwashers or washing machines.
Reverse-osmotic membrane filters
Special mention should be made of reverse osmosis systems equipped with special membranes (polyamides and acetyl cellulose, have a limited lifetime). They are able not only to remove hardness salts but also remove almost all elements of the Mendeleev table from the working environment. The output is distillate.
This means that installing these hard water filters in U.S. in a private home requires retrofitting. You need a mechanical pre-filter to protect the membrane and a chemical post-filter that will saturate the water with the minerals needed by man. This is not the most budget option: osmosis is quite expensive, the membrane needs to be changed regularly.
How to choose a hard water filter for your private home
For a private home or country cottage, all listed filtering options can be used when the system is properly planned. An expensive combined scheme may include reagent or magnetic installations for household appliances, reverse osmosis or ion exchange systems to produce clean drinking water. A more economical solution is universal hard water filters for private homes with ion exchange resins. Ideally with an automatic control unit.
Our experts will be happy to help you find the best hard water treatment solutions in the USA.