How to purify water without a filter?

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Denis Baigozin

Chemist, teacher, ex-lead developer of Aquaphor and author blog about chemistry.

It should be remembered that contaminants in water are not just particles visible to the eye, turbidity or color. The most toxic impurities - heavy metals, pesticides, etc. - are invisible to the eye or other senses.

To remove them, of course, it is better to use a professional filter. But if there is none, you are thirsty, and the water is not very clean, you can try to improve its condition manually.

Preparation

First, mechanical filtration must be done through a thick filter cloth (eg a heavy duty respirator). This will remove particles larger than 5 microns, such as insect larvae, rust and clay. Next, you need to boil the water, so volatile impurities (chlorine, chloroform) will leave it, and bacteria with viruses will die.

Basic cleaning

Then you can act in one of the following ways.

Option 1

To "collect" the dissolved impurities, you can use any good adsorbent: activated carbon, silica gel. Unfortunately, shungite, quartz and other popular stones do not work.

Next we need a column. It can be made from a regular plastic bottle: cut the bottom and turn it upside down. Fill the column with sorbent and run water through it.

If you cannot find an adsorbent, you can try to make it yourself. To do this, a red-hot coal from a fire is thrown into the water, then again into the fire, then again into the water. The surface of the coal is activated by hot steam. You can't get an industrial sorbent like that, but the coal will collect some impurities.

Option 2

Use freeze. For this, approximately half of the total volume of water is frozen in a bowl at a temperature of –1 to –5 ° C. With such a slow freezing, impurities do not pass into ice, but remain in liquid water. This water is drained, the ice is melted and subjected to repeated "semi-freezing". This leaves about ¼ of the original amount of water, but it is much cleaner than initially.

Unfortunately, none of these methods are as effective as even the cheapest water filter. If there are no options, then you can try, but I do not recommend taking risks. Remember, the water used must necessarily comply with SanPiNSanPiN 2.1.4.1074-01 Drinking water!