Water purification from heavy metals: methods and tools

Water purification from heavy metals, of course, is an important factor to get ready to use, clean and harmless to human fluid.For heavy metals are chemical elements that have metallic properties and thus have considerable atomic mass.

They have had a devastating effect on the function of organisms, animals and humans, and tend to accumulate in organs and tissues and cause irreparable damage to health.It is therefore important to establish treatment plants water filters from iron, copper, lead, nickel, zinc, cobalt, mercury, cadmium and silver.

need for such filtering due to the fact that due to the extensive use of water for various industries concentration of these metals in the stock is very high.Contaminants have different structures and properties, and therefore, for each of their species is necessary to resort to various methods and devices.

Water purification from heavy metals in the form of ions produced by chemical means and reduced to a change in the acidity of the medium to the desired.

Upon reaching the PH value of 9.0-10.5 any metals become insoluble and precipitate, which is simply eliminated.

Selection of chemicals, by means of which the industrial water treatment, depends on the following factors:

- required purity;

- the concentration of the pollutant;

- presence or absence of impurities.

After the substance transferred to the insolubilization step should separate them, often using gravity settling of the metal.Operation with the help of special besieging containers from which the settled particles are pumped for dewatering and drying.Plus, this method is its simplicity and negative - a high sensitivity to the presence of foreign compounds that can interfere with the deposition process.This may be soap, hydrogen peroxide or detergents.

Water purification from heavy metals is also produced by other means.It is called "membrane" and carried out by a special unit with partitions.Typically, the purified water membranes, metal concentrations less than 1 mg per liter, and a filter on the other side they are concentrated in a gelatinous mass.

Such water purification from heavy metals is considered to be the most effective and promising.Its high quality due to the special properties of membranes, such as: 1.

high selectivity, in other words, the capacity for separation of different properties of substances.Semipermeable partition and passes through it only water completely freed from impurities.Recent accumulate on the other side of the membranes.

2. The alloy from which the cast walls, is particularly strong and resistant to chemical attack.

3. The membrane is equally effective and fully implement the provisions of function throughout the period of use.The advantage of this method is that the impurity metals are not deposited on the filter surface and clog its pores and in many ways are removed from the membrane.

View this purification is reverse osmosis.This method is characterized in that a solution of (polluted water) applied pressure which exceeds its own.The disadvantages of the process are the high requirements to the quality of the materials from which are cleaning and installation complexity removing concentration layer.

large volume of liquid with a low concentration of heavy metals advisable purified by ion exchange.As is known, it is based on a technology using ion exchange resins which accumulates on the surface of the metal ions.Settings for these activities allow to maintain the resin in a few years, except for their caking.

the most thorough method of cleaning is the most complex technical execution of the cyclic process with ultrafiltration.However, this method applies only to electrolysis and galvanic industries, waste water contain a large percentage of waste solutions and saturated helanitami.For such work using special reactors.