Process for underground water purification from sulphureted hydrogen and/or sulphides

Description:

Invenfia refer! to a process for the purification of hydrogen sulphide and / or sulphide groundwater and can be used! in the process of treating groundwater or in standalone water purification filters.

In the Republic of Moldova about 50% of the groundwater does not correspond to the quality granules imposed for drinking water! They contain large amounts of pollutants such as fluorine, iron, manganese, sulphides, azotaphs, azotifes, ammonium. Sulfur ion concentration! in the southern areas of the country reaches values ​​up to! at 10 rng / L. According to the sanitary nuns sulphides should not! be present in drinking water. It is known, c! the presence of hydrogen sulphide and its acids in the water, together with the diminution of the organoleptic qualities, leads to the damage of human health due to! decrease in blood oxygen content. At present, in the Republic of Moldova the groundwater is not subject to the treatment processes.

The process of purifying the waters containing hydrogen sulphide and / or sulphides is known, what constitutes! in that c! initially the water is past! through a filter in the rail! ion exchange in form! bicarbonate and modified with copper ions, which are found in a coordinative state! with the amine groups of the ion exchange resins. After! this, the water is past! through an active carbon filter modified with silver ions [1].

The disadvantage of this procedure is! in that c! the purification process includes two! types of filters, which are expensive. Sulfur ions! they are chemically absorbed on the ion exchange resin, which leads to depletion of the anionite exchange capacity.

Also known is the process of purifying hydrogen sulphide and / or sulphurous waters! in the oxidation of sulfur ions! in the presence of active carbons В AU-A, CAS-23, CASO-23 by bubbling the water with air at different pH values ​​[2]. The disadvantage of this procedure is! in that c! Sulfur ions! it oxidizes! pan! to colloidal sulfur clogging! the pores of the active carbons thus rendering them inactive.

The problem I solve! invention const! in the elaboration of a process for the purification of groundwater of hydrogen sulphide and / or sulfides by catalytic oxidation! of the reduced compounds of sulfur with oxygen from the air using as active catalysts oxidized carbons impregnated with cations of iron or copper excluding the formation of colloidal sulfur that clogs! pores of the catalysts obtained at the base! of active warmth.

The process for the purification of groundwater, according to the invention, includes aerating the water in the presence of the catalysts obtained based on the oxidized active carbon, impregnated with copper or iron ions, during

30 ... 90 min, with an air flow of 10 ... 15 L / h! to 1 g of catalyst, the mass ratio! catalyst: ap! being 1: (350 ... 450) and water pH 7.5 ... 8.5.

The result of the invention is const! in that c! Sulfur ions! it oxidizes! catalytic up to! in sulfur compounds with a high degree of oxidation, excluding the formation of colloidal sulfur in the oxidation process. This fact is very important for c! it excludes the process of clogging the pores of the catalysts obtained at the base! of active carbon, which allows the catalyst activity time! either, practically, unlimited.

Example of carrying out the invention

The catalysts (CASO 23 Cu and CASO 23 Fe) were obtained from active carbon (CASO 23), which in turn was prepared from active carbon (CAS 23) obtained from peach kernels.

In a column! glass! with a diameter of 85 mm and a width of 400 ml of water was introduced in the 300 mm width! containing 10 mg / L sulfur! of sodium with a pH of 8.5, to which was added 1 g of catalyst obtained on the base! of oxidized active carbon, which has copper ions impregnated on their surface. The catalyst has a particle diameter between 0.63 ... 1.00 mm. By means of a device for dispersing the air with the help of a micropump, atmospheric air was blown with a flow of 12 L / hour! for 60 min. The mass ratio between oxygen and hydrogen sulphide undergoing oxidation was 3: 4. Such researches have also been carried out in the case of using the obtained catalysts based on! of oxidized active carbon, on the surface of which were impregnated iron ions.

The concentration of sulfur bases obtained by sulfur oxidation was determined after! completion of the aeration process.

The obtained results are presented in the table.

MD 3097 G2 2006.07.31

Table Concentration of sulfur bottoms obtained in the process of treatment of water contaminated with hydrogen sulphide and / or sulphides

<td rowspan="2">Catalytic support sample</td><td rowspan="2">The amount of H₂S</td><td colspan="4">Concentration of sulfur bottoms after aeration</td>

<td>S^u</td><td>s₂0₃²·</td><td>SO₃²’</td><td>SO₄²'</td>

<td>CASE 23</td><td> 12</td><td> 20</td><td> 4</td><td> 13</td><td> 63</td>

<td>CASE 23</td><td> 4</td><td> 6</td><td> 0</td><td> 28</td><td> 66</td>

<td>CASE 23 Cu</td><td> 41,6</td><td> 0</td><td> 9,3</td><td> 32,7</td><td> 58,1</td>

<td>CASE 23 Faith</td><td> 33,5</td><td> 0</td><td> 16,1</td><td> 17,7</td><td> 66,2</td>

(57) Claim: