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The liquid flowing in the centralized water supply system can only conditionally be considered suitable for use for technical purposes – washing, washing dishes, etc. With a big stretch, it can be used for cooking, but it is generally impossible to drink without boiling. To bring the water to normal, it is necessary to use different types of filters. There are inexpensive units, but they tend to have low productivity and average cleaning quality, and there are expensive systems that can give ideal results.
The situation is no better with water supply from a well or a well. There is still a high probability of bacterial infection, so cleansing should be even better. In general, it is necessary to take the sample for analysis, and then, based on the results, select the required types of filters. In private homes, this is usually a multi-stage system that results in potable quality water.
Coarse filters
The most common type, widely used in everyday life and at work. The water that flows in the water supply contains grains of sand, fragments of rust, metal, windings, etc. These impurities are called mechanical. Their presence has a bad effect on the durability of valves (taps, valves, etc.). Therefore, in apartments and private houses, filters are installed at the entrance to remove them. There are few types of filters for water purification from mechanical impurities. Usually it is with mesh or disc as filter element.
The filter element in mechanical filters is a mesh. According to the cell size, these filters are divided into coarse (300–500 microns) and fine (larger than 100 microns) devices. They can stand in a cascade – first coarse cleaning (mud), then fine. Often a coarse filter is placed at the inlet to the pipeline, and devices with a smaller cell are placed in front of a household appliance, since different equipment may require different degrees of water purification.
According to the orientation of the flask in which the filter element is installed, they are straight and oblique. Oblique create less hydraulic resistance, because this type is installed most often. During installation, the direction of flow must be observed, it is indicated by an arrow on the body.
Mechanical filter
There are two types of mechanical filters – with and without auto-flushing. Devices without autoflush are small in size, their inlet / outlet diameters are selected according to the dimensions of the pipe in which they are installed. Body material – stainless steel or brass, threaded connections are different, external or internal thread is selected as needed. The cost of this type of mechanical filters is low, although branded ones can cost much more.
Since the screens get clogged and need to be cleaned periodically, the lower part of the flask is removable. If necessary, unscrew it and wash the mesh. All work is carried out after shutting off the water.
Mesh with autowash
A mechanical filter with auto-washing (self-cleaning) has a branch pipe and a tap in the lower part of the flask with a filter element. The branch pipe is connected to the sewer with a hose or a piece of pipe. If it is necessary to rinse the filter, open the tap and pressurized water flushes the contents into the sewer.
This kind of coarse filter may contain a pressure gauge. It determines whether the grid is clogged or not. If the outlet pressure is lower than the inlet pressure, it’s time to clean the filter. With a transparent flask, there may not be a pressure gauge – contamination is determined by the appearance of the grid or the walls of the flask. In this segment, oblique water filters are rare, but still there are.
A pressure reducing valve can be integrated into the body to neutralize pressure differences. There are models with the possibility of installing an auto-flushing unit.
Tying this type of mechanical filter is a little more complicated – it needs to be drained into the sewer, but there are also models with different types of threads so that you can use as few adapters as possible.
Connection types
Mechanical cleaning filters can be coupling or flanged. Flanged are usually equipped with main water pipes with high pressures and diameters. But it can be used when arranging the water supply of a private house.
Disc filters
This type of equipment is less common, although it is less prone to silting, has a large filtration area, and can retain particles of different sizes.
The filter element is a set of polymer discs, on the surface of which depressions-scratches of different depths are applied. The discs in the assembled state are tightly pressed against each other, water passes through the hollows in the discs, while particles of a larger diameter settle on them. The movement of water is spiral, so that suspensions are removed efficiently.
When the water filter becomes clogged, the discs are removed from the housing, pushed apart and washed. Discs need to be replaced periodically. The service life of the filter element depends on the amount of dirt and the quality of the discs themselves. There are models with autowash.
They are mounted in a pipe break, the flask can be directed up or down, this is indicated in the installation instructions.
Inexpensive types of filters with water purification to drinking
Purified from mechanical impurities, water can be used for domestic needs, for example, supplied to household appliances. But for drinking it is suitable only conditionally – after boiling. In order to drink it without boiling, fine filters are needed, which retain a significant part of the substances dissolved in water and disinfect it. Consider how to make tap water drinkable and the types of filters that can be used.
Filter jug
The easiest, but not very productive way to make tap water drinkable is to pass it through a filter jug. Purification takes place in a replaceable cartridge through which water passes. A good cartridge contains the following filter media:
- polypropylene fibers for the deposition of residual mechanical impurities;
- activated carbon with additives to remove microorganisms and chlorine compounds;
- ion-exchange resin for removing manganese and calcium salts, radionuclides, iron compounds, heavy metals;
- porous activated carbon for water clarification, organic sedimentation.
Filter jugs differ in the composition of the cartridge, its resource (how much water it can clean) and in volume. The smallest models of desktop filters can purify 1,5-1,6 liters of water at a time, the largest – about 4 liters. Just keep in mind that the column “filter volume” indicates the volume of the bowl, the useful volume is much less – about two times.
| Name | Volume of the bowl | Cleaning module resource | Purification degree | Additional devices | Price |
|---|---|---|---|---|---|
| AQUAPHOR Art “Ice Age” | 3,8 liters | 300 l | Reduces water hardness, removes mechanical and organic impurities, active chlorine, heavy metals | 4-6 $ | |
| AQUAPHOR Prestige | 2,8 l | 300 l | Slightly reduces water hardness, removes mechanical, organic impurities, active chlorine, heavy metals | Resource indicator | 5-6 $ |
| AQUAPHOR Premium “Country” | 3,8 l | 300 l | Reduces water hardness, removes mechanical and organic impurities, active chlorine, heavy metals | Large funnel – 1,7 l | 8-10 $ |
| Filter jug Barrier Extra | 2,5 l | 350 l | Depending on filter type | Cassettes for different types of water they go to + to the cost of a jug | 5-6 $ |
| Filter pitcher Barrier Grand Neo | 4,2 l | 350 l | Depending on filter type | Cassettes for different types of water they go to + to the cost of a jug | 8-10 $ |
| Filter jug Barrier Smart | 3,3 l | 350 l | Depending on filter type | Cassettes for different types of water they go to + to the cost + mechanical resource indicator | 9-11 $ |
| Filter pitcher Geyser Aquarius | 3,7 l | 300 l | For hard water with bacterial treatment | Cartridge replacement indicator | 9-11 $ |
| Filter pitcher Geyser Hercules | 4 l | 300 l | From heavy metals, iron, organic compounds, chlorine | Receiving funnel 2 l | 7-10 $ |
Faucet filter attachment
Very compact filter for running tap water, which is put on the faucet. Cleansing rate from 200 ml/min to 6 l/min. The degree of purification depends on the composition of the filtering part, but usually differs little from pitcher filters.
According to the method of operation, there are two types of filters on the faucet – some are put on immediately before its use, others have the ability to switch to the “without purification” mode. More convenient, of course, the second option, but the switches often break. As a temporary measure – an excellent solution, but “permanently” it is better to choose another device.
| Name | Performance | Cassette resource | What cleanses | Manufacturer country | Price |
|---|---|---|---|---|---|
| Defort DWF-600 | up to 20 l/hour | 3000-5000 l | organic matter, pesticides, heavy metals, chlorine and radioactive elements | China | 2$ |
| Defort DWF-500 | up to 20 l/hour | 3000-5000 liters or 6 months | organic matter, pesticides, heavy metals, chlorine and radioactive elements | China | 2$ |
| Aquaphor Modern-1 | 1-1,2 l / min | 40000 l | from active chlorine, lead, cadmium, phenols, benzenes, pesticides | Russia | 13-15 $ |
| Aquaphor “B300” with bacterial post-treatment | 0,3 l / min | 1000 l | it is recommended to use in case of possible bacterial contamination of water | Russia | 4-5 $ |
| Geyser Euro | 0,5 l / min | 3000 l | carcinogenic and organic compounds, chlorine, iron, heavy metals, nitrates, pesticides and microorganisms | Russia | 13-15 $ |
| Philips WP-3861 | 2 l / min | 2000 l | chlorine compounds | $180 | |
| Sorbent RODNIK-ZM | 2 l / min | 3600 l | purification from free chlorine, iron removal | 8-10 $ |
Wash filters
For greater productivity and high-quality water purification, filters are used that are installed under or on the sink with wall mounting.
There are two types of such systems – cartridge and reverse osmosis systems. Cartridge ones are cheaper, and this is their plus, and the minus is that you need to monitor the condition of the filter element and change it in time, otherwise all the accumulated dirt goes into the water.
Reverse osmosis systems are already more technologically advanced equipment that has a much higher cost, but the quality of cleaning and productivity are much higher. These water treatment plants use a multi-layer membrane, each layer of which traps certain types of contaminants.
Cartridge
In cartridge filters, the quality of cleaning depends on the number of cleaning stages – individual filter elements that “catch” a certain type of pollution. There are single-stage systems, there are two, three and even four-stage filters.
In single-stage, universal inserts with a multilayer structure are used. They are inexpensive, but it is difficult to predict whether you will be satisfied with the degree of cleaning. The composition of water in different regions is very different and it would be desirable to select filters according to the composition of water.
In multi-stage cartridge filters, the housing consists of several flasks, each of which has a separate filter element that removes certain contaminants. The flasks are connected in series with overflows, flowing from one flask to another, the water is purified. In this case, it is possible to choose the types of filters specifically for your analysis, which will undoubtedly improve the quality of cleaning.
| Name of cartridge filter | A type | Number of cleaning steps | For what water | Cartridge resource | Performance | Price |
|---|---|---|---|---|---|---|
| BWT Sleep-Pure | Household with the possibility of washing | 1 cartridge + membrane | medium hardness | 10 l or 000 months | 1,5-3 l / min | $70 |
| Raifil PU897 BK1 PR (Big Blue 10”) | Trunk | 1 | cold tap water | $26 | ||
| Geyser Lux | under the sink | 3 | soft/medium/hard/glandular | 7000 l | 3 l / min | 70-85 $ |
| GEYSER GEYSER-3 BIO | under the sink | 3 + protection against viruses and bacteria | soft/hard/very hard/glandular | 7000 l | 3 l / min | 110-125 $ |
| Geyser-1 Euro | desktop version | 1 | normal/soft/hard | 7000 l | 1,5 l / min | 32-35 $ |
| Pentek Slim Line 10 | Trunk | 1 | 19 l / min | $20 | ||
| Expert M200 | under the sink | 3 | normal/soft | 6 – 000 l depending on the cartridge | 1-2 l / min | 60-65 $ |
| Brita On Line Active Plus | under the sink | 1 | flowing | 2 l / min | 80-85 $ | |
| AQUAFILTER FP3-HJ-K1 | under the sink | 4 + protection against bacteria and viruses | for cold water | 3 l / min | 60-90 $ | |
| Barrier Expert Hard | under the sink | 3 | for hard water | 10 l or 000 year | 2 l / min | 55-60 $ |
| Atoll D-31 (Patriot) | under the sink | 3 | highly chlorinated water | 3,8 l / min | $67 |
Desktop cartridge filters for running water
The most inexpensive version of cartridge filters is installed next to the sink and are small in size. They can be one or two-stage, there is a small tap on the body. The filter is connected with hoses to a special mixer outlet or directly to the water supply.
Trunk
These are usually cartridge single-stage filter flasks, which are placed after a mechanical filter. They remove a significant amount of impurities, making water suitable for drinking and protecting household appliances from the formation of scale and other deposits. Their disadvantage is the need to change the filter elements.
For the convenience of monitoring the state and degree of contamination, the flask is made transparent. In case of severe contamination, it is necessary to replace the cartridge with another one. In some models, it is possible to restore the performance of the cleaning element after washing it under running water. In other models, this is prohibited, so read the instructions carefully.
Multistage filters
They differ from those described above by a large number of flask cases, each of which has a cartridge that removes various types of contaminants. The more stages of purification, the cleaner the output water is. It is necessary to select the composition of the filter elements for the specific composition of the water.
These installations can be placed under the sink and provide high quality drinking water.
Reverse osmosis
The most advanced water purification technology today is reverse osmosis. The system uses multilayer membranes that allow only water and oxygen molecules to pass through, not passing small contaminants. Water is obtained practically without salt content, which is also not good. This is the main disadvantage of reverse osmosis systems. To neutralize it, the installations are equipped with mineralizers that add the necessary minerals.
| Name | Number of cleaning steps | Resource / frequency of replacement | Filtration speed | Notes | Price |
|---|---|---|---|---|---|
| Geyser Prestige 2 | 6 | 1 once a year | 0,15 l / min | Purified water storage tank 7,6 l | 70-85 $ |
| Atoll A-450 (Patriot) | 6 | pre-filters – 6 months, membrane – 24-30 months, carbon post-filter – 6 months. | 120 l/day | Has an external tank | 115-130 $ |
| Barrier Profi Osmo 100 | 6 | 1 step – from 3 to 6 months, 2 steps – every 5 – 6 months, 3 steps – from 3 to 6 months, 4 steps – from 12 to 18 months (up to 5000 liters), 5 steps – every 12 months | 12 l / h | Has an external tank | 95-120 $ |
| Aquaphor DWM 101S Morion (with mineralizer) | 6 | pre-filters – 3-4 months, membrane – 18-24 months, post-filter mineralizer – 12 months. | 7,8 l / h | External tank + mineralizer | 120-135 $ |
| Barrier K-OSMOS (K-OSMOS) | 4 | 5000 l (no more than a year) | 200 l/day | External tank | 120-150 $ |
| Atoll A-450 STD Compact | 5 | pre-filters – 6 months, membrane – 24-30 months, carbon post-filter – 6 months. | 120 l/day | External tank | $150 |
The disadvantages of this system include their low productivity – only one glass or so of clean water can run per minute. It is clear that such a speed causes inconvenience, so that it is felt less, manufacturers complete the installations with tanks for purified water, to which taps are already connected.
Filters for purification of water from dissolved substances
In addition to mechanical impurities in tap water, there is also a decent part of the periodic table: iron, mercury, manganese, potassium, calcium (hardness salts from which scale forms), etc. They can be removed, but different filters are needed for this.
To remove iron
Most often, water from wells or wells contains a lot of iron. It gives the water a reddish tint and a specific taste, is deposited on the walls of plumbing fixtures, and clogs shutoff valves. It makes sense to do this if the amount of iron exceeds 2 mg / l.
Divalent iron dissolved in water can be removed from the water using a catalytic filter. This is a large cylinder into which catalysts are poured, the work is controlled by a small processor, that is, this equipment requires power supply.
The backfill located in the catalytic filter greatly accelerates the process of oxidation of ferrous iron and its precipitation. Depending on the backfill, impurities of manganese, chlorine, and other substances dissolved in water can also be removed, and mechanical particles also settle to the bottom during the cleaning process. Removal of accumulated deposits occurs according to a predetermined schedule, usually at night. The backfill is washed under the pressure of water, everything is drained into the sewer, for the time of washing, the water supply stops. Catalytic filters are complex and expensive equipment, but they are the most durable in existence.
Another way to remove iron and water is aeration. In a cylinder with pumped air, water is supplied in the form of a fine suspension. The iron in it reacts with atmospheric oxygen and its oxides are filtered out at the outlet. There are two types of aeration filters – pressure and non-pressure. For more active oxidation, an oxidizer — hydrogen peroxide or sodium hypochlorite — can be supplied to these plants. In this case, biological treatment of water from microbes and bacteria is also carried out.
Read more about purifying water from a well and a well here.
Purification of water from hardness salts
To soften water, filters with ion exchange resins are used. In the process of interaction with water, harmful impurities are replaced with neutral or useful ones (an increase in the amount of iodine and fluorine).
Externally, this equipment is a tank partially filled with ion-exchange material. Paired with it is a second similar regenerator tank filled with a highly concentrated salt solution. It is sold special in tablets with a high degree of purification.
The advantages of installations of this type are high productivity, low noise level during operation and a rare replacement of backfill, it lasts for 5–7 years. For water softening, ion exchange filters are the best choice. The disadvantages are the need to use a regeneration tank with concentrated brine. To get drinking water, you need to install an activated carbon filter.