How to purify water from a well: filters and folk methods

If the water comes into the house from a well, it may contain various impurities such as sand, clay, iron, manganese, nitrates and bacteria. Special equipment such as sumps and filters are required to treat such water.

To properly select equipment for water purification from the well, it is necessary to conduct its chemical analysis. It is desirable to make a detailed analysis to obtain more accurate information about the composition of water and select the most effective equipment.

Depending on the results of the analysis, purification from various impurities and bacteria may be required. For example, to remove iron and manganese, special filters are used, and to remove nitrates and bacteria – aerators and settling tanks.

Steps of purification

Purification of water from a well passes in several stages:

In each specific case, the number of purification stages is determined based on the analysis of water from the well. If the content of any substances exceeds the norm, ways to reduce their concentration and equipment for this purpose are selected.

About auto irrigation systems can be read here.

How to purify water from the well from sand

Removal of sand or particles of clay, silt, other large particles occurs on the filter lowered into the well. Do it with simple mechanical filters – plate or sand, and call this stage a stage of coarse purification.

If there is a lot of suspended solids, one filter will not do: it will quickly clog. It is more practical to put a system with cells of different sizes. For example, water from the well falls on the filter that captures particles up to 100 microns in size, then installed a filter with a degree of purification to 20 microns. They will remove almost all mechanical impurities.

Types of filters

Coarse filters can be mesh, cassette (cartridge) or backfill filters. Mesh filters are most often placed in the well itself. They are a hollow pipe of slightly smaller diameter than the wellbore. In the walls of the pipe drilled holes or slots (the shape of the holes depends on the soil), on top of the coiled wire, and on it – the grid. The mesh is chosen depending on the type of soil in the aquifer: it should hold the bulk of contaminants and at the same time not be clogged. At this stage, the largest impurities are trapped, which in addition can damage the pump. However, some solids still rise to the surface. They are removed in the process of further cleaning.

Sometimes it is not possible to put a filter in the well. Then all purification is transferred to the surface. To purify water from the well in this case, cassette or backfill filters are used. In cassette filters there is a replaceable cartridge – a system of membranes, crushed charcoal, etc. on which sand and other large contaminants settle.

From time to time, the cartridges become clogged and need to be replaced. The frequency depends on the degree of water contamination and the intensity of water use. Sometimes one cartridge is quickly clogged. In this case, it makes sense to put two filters with different degrees of purification. For example, the first one detains particles up to 100 microns, and the one behind it is already up to 20 microns. This way the water will be clean and the cartridges will have to be changed less often.

In backfill filters, loose filtering material is poured into the container – sand, crushed shells, special filtrates (for example, BIRM). The simplest mechanical filter is a barrel with sand, which has a washing function. One nuance: if there is a large amount of dissolved iron, it is still preferable to pour in special filtrate, it is also a catalyst that oxidizes dissolved iron and manganese, causing them to precipitate.

Depending on the particle size of the backfill of such a filter, quite small particles can be detained. Sometimes they put two such filters in a row, only with different backfill – first the water enters the one where the filtrate has a large size, then with a smaller filling. Bulk filters for water purification from the well are good in that they require replacing the backfill about once every three years. And this is how they differ from plate filters, whose filter must be changed much more often: sometimes once a month, sometimes – once every three to six.

But in order for cleaning by means of a backfill filter to be effective, they need periodic washing of the filtrate. This is usually done by shutting off some faucets and opening others. In this case, the water flows in a different direction, flushing out the bulk of the accumulated sediment.

An example of assembling two consecutive filters for purifying water from coarse impurities, see the video.

How to make a chute for cleaning a well can be read here.

How to purify water from a well from iron

The most common problem with water lifted from wells is excessive iron content. If we talk about sanitary norms, the permissible level of iron in water is 0.3 mg / l. If the concentration increases, a specific flavor appears. If the iron content is more than 1 mg/l, the color changes – after a short retention appears characteristic reddish – rusty – tint.

There is no reliable data on the occurrence of pathology or the development of any disease when drinking water with an increased amount of iron, but drinks and food are not the most attractive look and taste. But such water can help with low hemoglobin in the blood, if you drink it long enough. Nevertheless, water from iron is more often purified, and at least to sanitary standards. The reason is that iron is deposited on household appliances, which is often the cause of its failure. To remove iron from water, there are several types of equipment.

Reverse osmosis

This is probably the most effective method: almost all particles are removed. In this water purification equipment there are special membranes that allow only H2O molecules to pass through. All the others are deposited on the filter. A special purification system allows automatic removal of accumulated contaminants, which are discharged into the sewer or drain pit.

Reverse osmosis removes not only iron, but also all other dissolved substances in the water. Insoluble particles such as sand and trivalent iron (rust) are a problem: they clog the filters. If you have a large number of these impurities, coarse filters (described above) will be necessary before the reverse osmosis equipment. Another nuance: this equipment is installed on the water pipe and works under a certain pressure.

And yet the main disadvantage of such a system is its high cost, and filters are also not cheap, and change them with approximately the same frequency as in cartridge installations (once every one to three months). Therefore, most often this equipment is put for the preparation of drinking water – installed under the sink, take out a separate faucet and use only for drinking or cooking. To purify the rest of the water – for technical needs – use other methods and ways.

Filters for water purification from a well with ion-exchange resins

According to the device, they are very similar to cartridge filters, but there are special filters with resins that replace iron with sodium. At the same time, water softening takes place: magnesium and potassium ions are also bound. This equipment has several types of devices. For small volumes, cartridge filters are suitable, for large volumes they are no longer enough, and install filter columns that can provide clean water at a significant flow rate. That is why, when selecting filters and equipment for water purification from the well, the average and peak flow rate is also required: to correctly select the performance.

Removal of iron from water by aeration

Filters for water purification from a well are effective, but far from cheap equipment. The problem can be solved more simply: with the help of aeration. The fact is that in water there is iron in two forms: dissolved divalent form and precipitating trivalent. The principle of aeration is based on the addition of oxygen to the water, which oxidizes the divalent iron dissolved in the water to trivalent iron, which precipitates in the form of rusty precipitate. In addition to rust, this method neutralizes manganese, hydrogen sulfide (gives the smell of rotten eggs), ammonia.

Pressure aeration systems

According to the device, aerators can be divided into non-pressure and pressure aerators. Pressure aerator consists of an aeration column and a compressor that blows air. There is an automatic drain valve at the top of the column that drains excess air. It can get water in it, so it is connected to the sewage system.

Water is drawn from the lower third of the aeration column, but not too low, as insoluble sludge – the result of purification – accumulates at the bottom. The system is only switched on when there is a flow rate. For this purpose there is a flow sensor at the outlet. As soon as the faucet is opened, the compressor is turned on, closed, it is turned off.

Pressure aeration system is also not the cheapest pleasure. But it is necessary if the content of iron or other dissolved substances is exceeded by 30 or more times. Otherwise, you can’t get rid of so much pollution: the filters will clog very quickly.

Unpressurized aeration water treatment systems

The second type of aeration system is a non-pressurized one. It has a large tank in which the water stands. The volume of the tank – from 600 liters, but in general it depends on the water consumption: it should be consumed no more than 50-60% of the available volume, so that the sediment remains at the bottom.

Water is supplied to the tank directly from the well. The water level can be controlled by sensors of the lower and upper level or, as on the photo, by a float switch of the well pump. To protect the system from overfilling, just above the critical level, a water discharge pipe is made. It can go into the drainage or sewage system. It is important that there are some visual sensors that there is too much water in the tank.

This system works as follows: water is drawn into the tank up to the required level, after which the pump is turned off. To purify the water includes a compressor (can be powerful for aquariums), which supplies air to the tank. It is distributed through a diffuser, which is located at about half the depth.

To ensure constant pressure in the system, water can be pumped out of the tank using a pumping station. The water is drawn from the lower third, but not from the bottom (via tap 1): the cleanest water accumulates here. It flows through tap 3 to the pumping station and from there through the tee and tap 5 into the system.

The scheme above also includes a purification system. In this case, tap 2 and tap 5 are closed and tap 2 and tap 4 are opened. The sediment from the bottom in this position is drained into the sewer or drainage system. After the sediment has been removed, some more clean water must be drained to flush all pipes well. Only when clean water goes into the sewer, all taps can be returned to their original position.

About drip irrigation systems you can read here.

Water purification systems from the well with their own hands

One of the variants of homemade water purification from a well by the method of aeration is demonstrated in the photo below. Here two stages of aeration are used for more complete water purification and removal of all impurities. The need for the second stage is determined based on the results of cleaning the first stage: not always the quality is satisfactory. Repeated aeration can help, but it is not the only solution: you can put one of the filters. It will do the job well, and it will rarely clog.

In this option, water from the well is supplied through the showerheads. Thus there is a primary enrichment with oxygen. There is also a submerged atomizer from an aquarium compressor. The water level is controlled by a float switch (used for pool water control). There is a tap at the bottom of the tank for draining settled water.

From the first tank, water is drawn from the lower third as in the previous variant. the system there is organized similarly. From there, the water can be fed to the filter for final purification and disinfection, and then it is distributed around the house.

Another example of a homemade water purification system from a well, see the video.

Tips for homemade water purification

If we talk about homemade systems, water purification from a well, then often use different approaches and methods. Here are a few quotes:

I remove iron cheaply and simply. I have a tank for 120 liters. I pour 7-10 grams of lime into it, then 4-5 hours blowing compressor from the aquarium and 3 hours let stand. Then I feed the water to the filter with a cartridge for 2 microns, and from there into the system. This method made in the country. I change the filter once a month. Friend at home made a larger system – for 500 liters. There work two compressors 12 hours. If you increase their power, the time can be reduced.

The second option is no less interesting:

I had a lot of sand and silt coming from the well: my flow rate is large, and “pulls” a lot of all sorts of crap. I solved the problem by installing a filter. Only the native cassette gutted (after the filter became unusable), and in it poured crushed shells. Some people pour marble crumbs. Works well too. Only the fraction you need not fine, or it will quickly clog. And then I have a tank with blowing (aeration), and after it is already a filter that removes that the first two could not. The last filter I have is a barrel with BIRM backfill. It has a tap for flushing. So every couple of weeks I wash the backfill, and it needs to be changed after three years.