Hard water. This phrase is firmly entrenched in our minds. But what do we know about her? That it is very difficult to wash in it - the powder does not wash, and the fabric becomes unpleasant to the touch. We also know that water with an increased level of hardness is harmful to skin and hair. It causes dryness and flaking. We have also heard that it causes scale formation on electrical appliances and failure. But where does rigidity come from, what is its effect on human health and, most importantly, how to deal with it? Today we will help you figure it out.

What water is called hard

Hardness is a characteristic of water, which means the level of hardness salts dissolved in it. These are mainly calcium and magnesium salts.

The term "hard water" is actively used in everyday life. However, not everyone fully understands the meaning. It does not indicate the direct properties of water. We cannot determine the hardness or softness by touch. This term originated from the fact that fabrics that are washed in such water become less soft and pliable. The reason is the porous structure of the fabric, which is capable of attaching salts formed during washing.

Where does the increased water hardness come from?

Although we are used to associating environmental problems with human activities, it has nothing to do with the hardness of natural water from sources. The reason lies underground. More precisely, in the deposits of rocks: gypsum, limestone, dolomites. Groundwater dissolves these rocks. Cations of calcium and magnesium and other metals appear in water, which react with anions and directly affect hardness.

Therefore, there is hard water in underground springs and in a well. Fresh water in surface springs is softer than underground ones. However, surface waters have a greater hardness in winter. But with the onset of spring, melt water enters them and reduces the hardness.

Types of water hardness

Total hardness expresses the total amount of salts in the water. In turn, it is subdivided into two types: temporary (carbonate) and permanent (non-carbonate). The visible difference is in the formation of a precipitate when heated. Salts of temporary hardness precipitate, and permanent salts, on the contrary. Temporary hardness is special due to the content of hydrocarbonate or bicarbonate g fiver water purifier compounds, which decompose when boiled and form water, carbon dioxide and calcium carbonate. Therefore, the temporary hardness is completely or partially eliminated by boiling. The situation is different with constant rigidity. It arises from the content of chlorides, sulfates, phosphates, nitrates and other elements in salts. It is impossible to get rid of it by heating water. Substances do not disintegrate and do not form a precipitate. And in excessive quantities, they harm human health. When cleaning water, it is important to pay attention to temporary and permanent hardness.

How is water hardness measured?

On the territory of the Russian Federation, it is measured by degrees of hardness. I will give a comparative table of measurements in different countries:

In different cities of European countries, the stiffness indicator differs significantly. For comparison, I will give a table:

Hard water quality

The hardness index significantly affects the taste of drinking water. It takes on an unpleasant bitter taste. However, there are no unequivocal requirements regarding the permissible level of rigidity. It all depends on the specific area of ​​residence. For some consumers, there is one permissible norm, while for others it can be 2 times higher.

The World Health Organization, in a number of its materials, points out the connection between stiffness and some diseases. However, according to experts, these data are not enough to establish an acceptable indicator. According to the state standard of the Russian Federation, the hardness of drinking water should not exceed 7 mg-eq / l. But for heating and water heaters, the properties of hard water are of great importance. After all, the higher it is, the more likely the formation of slags and scale in pipes, boilers and kettles. Therefore, the most acceptable indicator is less than 4 mg-eq / l.

A significant drawback of hard water is the weak foaming of detergents. This causes significant cost overruns. And after drying, an invisible plaque forms on the surface of linen, plumbing, washed surfaces, and even human skin and hair.

At the same time, too soft water with an indicator of less than 2 meq / l has a low alkalinity. This entails an increased tendency for water pipes to corrode. Therefore, it is important to strike the right balance between hardness and softness.

I will give a table of stiffness indicators and classification:

The effect of hard water on the human body

Hard water contains elements, the excess of which negatively affects health. Moreover, this influence has visible and invisible consequences. Let's consider them in detail.

The skin's reaction to hard water is most noticeable and manifests itself almost immediately. Hardness salts react with substances in shampoo and other cosmetics and form a special foam that is difficult to wash off. After it dries, a film appears on the surface of the skin.

The main harm of hard water and this sediment is the destruction of the natural sebaceous film, which is always present on the skin of a healthy person. She is a protective mechanism of the skin and resists microbes and aggressive manifestations of the external environment. Hard water dries the skin, promotes flaking and allergies. Because of her, dandruff worries, which even special shampoos do not help get rid of. The disappearance of the protective fatty film contributes to the appearance of wrinkles and the rapid aging of the skin.

Less noticeable is the effect of hard water on the digestive system. More often than not, we attribute these effects to the food eaten. However, the properties of hard water often cause disruption of the stomach and intestines. They form compounds with animal proteins from food and accumulate in the digestive organs, settling on the walls. Salts can disrupt fermentation and contribute to the accumulation of toxins.

Hard water harms the heart and blood vessels. An excess of calcium and magnesium leads to disruption of the heart muscle. However, the lack of these elements threatens problems with the cardiovascular system. Water hardness filters help avoid these problems. They contribute to the normal balance of water hardness. Problems with the musculoskeletal system. Our body is motivated by the synovial fluid, which lubricates our joints. Drinking water with increased hardness contributes to the accumulation of minerals, which significantly hinder the body's motor abilities. Pain occurs when flexing and extending the joints.

Until recently, hard water was attributed to the appearance of stones in the kidneys and biliary tract. However, research by scientists has dispelled this misconception. In fact, stones do not appear with an excess, but with a lack of calcium. If the body does not get enough of this element from food, then it begins to take calcium from the bones. Most of it is not absorbed and forms stones in the internal organs and spurs on the bones. At the same time, an excess of magnesium in water does not allow calcium to be properly absorbed and displaces it from the body. Therefore, partially hard water is the reason for the appearance of stones.

How to determine increased water hardness at home

Outwardly, water with increased hardness does not differ at all from ordinary water. It often has no specific odor or turbidity. And only analysis will show the exact content of hardness salts. However, there are several signs that will unmistakably indicate its presence and will help to avoid the harm of hard water.

Take a look into the kettle. Scale is the main symptom. If scale appears on the heating element in the electric kettle, then rather take care of the elimination of stiffness. After all, this phenomenon can not only affect the performance of water heating devices, but also threaten human health.

Bathroom taps and shower head. If you notice that even after washing with plain water without detergents, white stains remain on them, then this is a sign of an increased content of calcium and manganese salts. The same goes for the stone in the shower head.

Skin reaction. The human body reacts sensitively to exceeding the permissible water hardness. The main signs: after taking a bath or shower, you feel dry and tight skin, itching and peeling worries.

The amount of foam. In such water, detergents foam much worse than in water with normal hardness. This makes it difficult for particles of the agent to penetrate into the surfaces to be cleaned. As a result, we get uneconomical use of household chemicals.

Water softening methods

Water softening is the elimination or minimization of hardness salts in the composition. To determine the need for this process, a water analysis is performed. Only on the basis of the results are conclusions drawn about the indicator of water hardness. The following methods are used for softening:

heat treatment;

chemical treatment;

physical methods;

membrane method;

ion exchange.

Next, we will consider each of them and identify their strengths and weaknesses.

Heat treatment

In simple terms, boiling. This method is one of the most common for water softening at home. As we said in the wound, when heated, bicarbonate compounds (which cause hard water) break down and form a sludge. In this way, partial elimination of hard water is possible.

The advantages of the method include ease of implementation, low cost and the ability to soften water at home. It does not require additional equipment and materials. Disadvantages of the method:

small volume of the obtained purified water;

it is necessary to wait until it cools down;

the formation of scale on the dishes for boiling;

incomplete elimination of hardness salts.

Chemical treatment

This method involves the extraction of hardness salts using chemical reactions. Special substances are added to the water - reagents. Their task is to neutralize calcium and magnesium ions. This is due to precipitation. Reagents are selected based on the initial composition of the water. They can be: lime, caustic soda, soda ash and baking soda, synthetic reagents. Let's take a look at the ways and cases in which they are applied.

Lime. It is used to soften water with high carbonate hardness and low non-carbonate hardness. In addition to lime, coagulant reagents are added.

Lime and soda. The combination of these substances makes it possible to obtain soft water with a hardness index of up to 1.4-1.8 mg-eq / l.

If carbonate hardness is significantly expressed in water, then a sodium-soda reagent is used.

Synthetic reagents. It is a cocktail of substances that effectively deal with water hardness. For example, capsules and tablets for dishwashers and washing machines.

The use of water softeners can significantly reduce hardness and remove suspended solids. However, this approach has several disadvantages:

the appearance of waste that requires further disposal;

accurate calculation of the dose of the substance. Otherwise, unusable and even toxic water is obtained;

after using the reagents, the water becomes suitable for domestic purposes only. Cannot be used for drinking or cooking. The only exception is baking soda. However, the disadvantage is partial water purification.

reagents require special storage conditions.

Physical methods

Combine several methods of water purification from hardness salts, which are based on physical processes:

Electrodialysis. It consists in the movement of ions to the electrodes. Thus, the metals that make up the hardness salts are retained.

Magnets. Water passes through magnetic fields of different directions. In the course of this path, large compounds are formed that precipitate.

Magnetic ionization method. Similar to the previous one, however, ionization is used for better results.

Ultrasound. The principle of operation is similar to the magnetic method. Large particles are also formed.

Electromagnetic radiation. A method that began to be applied not so long ago. Under the influence of electromagnetic waves of a certain frequency, metal ions lose the ability to create scale and settle. This way of dealing with hardness is good for both preventing scale build-up and for peeling off existing build-ups.

Membrane method

The main tool is high pressure, under which water is passed through a translucent film (membrane). It retains impurities and allows only water molecules to pass through. The obtained water is similar in its properties to distilled water. This is an almost ideal method, which gives a high quality of the resulting liquid.

However, there are several significant disadvantages:

a lot of pressure is required;

water is purified, but additional mineralization is required for its use;

expensive equipment and materials.

Ion exchange

This softening method is based on the exchange of hardness ions in water (calcium and magnesium) with ions of filter materials (sodium). The filtering materials are special fine-grained resins.

The constant exchange of ions leads to the disappearance of ions from the load, therefore replacement or restoration is required. With the replacement, everything is clear. But what is recovery? This is a process when a special solution is passed through the spent resin. Most often, ordinary table salt is used in filters for cleaning hard water. It gives sodium ions to the load, and hard metal ions are replaced and eliminated.

There are several types of filters that work with this method:

with temporary cartridges that require replacement;

a flask with a load that requires replacement;

recoverable filters. Feature - in the presence of additional equipment with a cleaning load.

Ion exchange is a method that allows you to get well softened water in a short time. Another feature is its long service life. However, there are several disadvantages:

non-remanufactured filters require replacement of the load or cartridges.

equipment price.

Combined approach

Each method is selected based on some features: the initial content of hardness, the presence of additional impurities, a source of water, an object for placing equipment. In some cases, several methods are used at the same time to achieve maximum softened water.

Instead of conclusions

Water softening is an important step in cleaning. Hard water can damage boilers and kettles, lead to the formation of scale inside the heating pipes. It is also poor in taste, undrinkable and can cause health problems.

The properties of hard water do not allow it to be fully used for domestic needs. Therefore, be sure to pay attention to softening. And Prof Water is ready to help you with this. We will conduct a free water hardness test and determine the level. And we will help you choose the equipment that is suitable for your well or well so that you and your loved ones enjoy only high-quality water.