SU1463720A1 - Method of deep purification of waste water from organic dyes and surfactants - Google Patents

Abstract

The invention relates to wastewater treatment methods and allows for increasing the degree of purification and reducing the cost of electricity. Sewage water is treated in the electrolyzer in the presence of chlorine ions in stages. The electro-oxidation in the first stage is carried out to a residual active chlorine content of 70-80 mg / l; the drain is directed to the catalytic reactor, then again subjected to electro-oxidation to a ratio of the concentration of residual active chlorine to the residual COD of 0.8-1.2, followed by catalytic oxidation in the reactor containing pyrolusite. Catalytic oxidation at each stage is carried out until the full utilization of active chlorine. The method allows to reduce the degree of water purification in comparison with the prototype by 1.5-2.0 times while reducing the cost of electricity. 3 tab. (/)

Description

one

The invention relates to methods for the removal from wastewater of difficult-to-oxidize organic dyes and synthetic surface-active substances (synthetic surface active substances) and can be used for the purpose of deep purification of wastewater from textile and knit finishing and dyeing; enterprises for the production of dyes and intermediates, household chemicals, leather and haberdashery factories, etc.

The purpose of the invention is to increase the degree of purification and reduce the cost of electricity.

When treating wastewater in an electrolyzer with insoluble anodes in the presence of C1-IONS, the latter are

It is formed on the anode to form in the volume of a solution of active chlorine, which enters into an oxidation-reduction reaction with organic compounds present in the wastewater, and is reduced to chlorides, re-discharging with the formation of active chlorine. At the same time, the concentration of the oxidizing agent — active chlorine — increases all the time, while the concentration of the reducing agent — organic compounds — decreases. When a residual active zslore concentration of 70–80 mg / l is reached, the wastewater is directed to a catalytic reactor containing pyrolusite.

When restoring active chlorine on a heterogeneous catalyst, it is about a & dH ISO

The resulting atomic oxygen, the hemolytic oxidation of the hardly oxidizable organic compounds (w. Catalytic oxidation, e), makes full use of the residual active chlorine and re-directs the water to the electrolyzer. The electro-oxidation is carried out to a ratio of residual active xtriopa to a residual COD of 0.8-1.2, and catalytic oxidation in a pyrolusite reactor is dried until the active chlorine is fully used to reduce the active chlorine.

The ratio of C "Art. color / QHP is varied by changing the residence time of the waste liquid in the second stage electrolyzer-oxidizer.

The results of the experiments are presented in Table. 2

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As can be seen from the table. 2, the optimal ratio of the concentration of residual active chlorine to the residual COD after electro-oxidation on the next stage. If necessary, the number of the stages of treatment is 15

 processing, incl. Electro-0.8-1.2 mg / mg. At large, the correlation is chemical and catalytic (g is oxidized

HHBj may be increased, while

at each subsequent electron stage, the rate of mineralization of organic compounds decreases and the total voltage on the electrolyzer increases significantly, which leads to increased power consumption. Table 3 compares the results of water purification using the proposed method and the known method.

c | acidification leads to the ratio of the concentration of active chlorine and COD, equal to os8-1.2,

Example 1. Sewage water, 51, concentration of SPA15 62 mg / l and EPK 932 mg / l, is treated in an electric 25 liter-oxidant at a current density (50 A / m2 and a dose of NaCl - 5 g / l. Concentration residual active chlo-ijsa change5 change time

Their mineralization rate of organic compounds decreases and the total voltage on the electrolyzer increases significantly, which leads to increased power consumption. Table 3 compares the results of water purification using the proposed method and the known one.

-Analysis of the results in table. 3. shows that the cleaning effect on the COD Bbmie at the second stage of processing at A0%, and at the third at 45%. In addition to the water in the electrolyzer, this is the effect of cleaning with a synthetic surfactant at the age of the pastor.

The results of the experiments are presented in tablo 1.

. As can be seen from the table. 1., the optimal | value of the concentration of residual active chlorine in the first stage of purification. After the electrolyzer-oxidant is 70-80 mg / l. With an increase in the concentration of residual active chlorine, the rate of mineralization of organic compounds decreases, and the rate of accumulation of residual active chlorine increases.

Sewage water treated in the first stage with the claimed parameters is subjected to repeated electro-catalytic oxidation. At the same time, the current density and the dose of NaCl in both stages during the electro-oxidation process are supported respectively by I 150 A / m2 and Cfigcfc.- 5 g / l. Catalytic filtration in both stages leads to complete oxygen-chlorine.

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melts by 40 and 64% in the second and third stages, respectively.

Udelniy power consumption for the proposed method is less by 0.7 kWh / m in the two-stage and 0.2 kWh / m in the three-stage processing, compared with the known method.

Thus, the proposed method allows to increase the degree of water purification while reducing costs.

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SO

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Formula of invention

A method of deep wastewater treatment from organic dyes and surfactants, including treatment in an electrolyzer with insoluble electrodes in the presence of chlorine ions and subsequent catalytic oxidation, characterized in that, in order to increase the degree of purification while reducing electricity costs , treating wastewater by liquidator in the electrolyzer to a residual active chlorine content of 70-80 mg / l, and

Crystalline recovery of active chlorine.

The ratio of C "Art. color / QHP is varied by changing the residence time of the waste liquid in the second stage electrolyzer-oxidizer.

The results of the experiments are presented in table. 2

0.8-1.2 mg / mg. At large ratios, the rate of mineralization of organic compounds decreases and the total voltage on the electrolyzer increases significantly, which leads to increased power consumption. Table 3 compares the results of water purification using the proposed method and the known method.

-Analysis of the results in table. 3. shows that the cleaning effect on the COD Bbmie at the second stage of processing at A0%, and at the third at 45%. In addition to the effect of cleaning on detergent age 35

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melts by 40 and 64% in the second and third stages, respectively.

Udelny power consumption for the proposed method is less by 0.7 kWh / m in the two-stage and 0.2 kWh / m in the three-stage treatment compared with the known method.

Thus, the proposed SPO. This allows you to increase the degree of water purification while reducing costs.

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SO

55

Formula of invention

A method of deep purification of wastewater from organic dyes and surfactants, including treatment in an electrolyzer with insoluble electrodes in the presence of chlorine ions and subsequent catalytic oxidation, characterized in that, in order to increase the degree of purification while reducing the cost of electricity, wastewater treatment gvodod t in the electrolyzer to the content of residual active chlorine 70-80 mg / l, and after catalytic oxidation, are treated in the same cell to the ratio of the concentration and residual active chlorine to residual chemical consumption

14637206

oxygen 0.8-1.2: 1 and catalytic oxidation, and in both cases catalytic oxidation is carried out to the full use of active chlorine.

Spreadsheets

Tabli.tsa 3

Claims (1)

Claim The method of deep wastewater treatment from organic dyes and surfactants, including treatment in an electrolyzer with insoluble electrodes in the presence of chlorine ions and subsequent catalytic oxidation, characterized in that, in order to increase the degree of purification while reducing energy costs, wastewater treatment is carried out in an electrolyzer to a residual active chlorine content of 70-80 mg / l, and 1463720 6 oxygen 0.8-1.2: 1 and catalytic oxidation, and in both cases, catalytic oxidation about the full use of active chloro5 after catalytic oxidation, they are processing in the same electrolyzer to the ratio of the concentration of residual active chlorine to residual chemical consumption Table 1 The concentration of residual active chlorine, mg / l The total voltage on the cell, and, V L ' The volume of foam condensate,% of the volume of runoff 64.8 3.84 1,64 70.1 3.84 1.8 75.3 3.85 1.9 80,4 3.86 2.05. 85,2 3.92 2,4 90.1 4.02 2.86 in the cell The cleaning efficiency,% The ratio of residual active chlorine to residual COD, The total voltage on the cell, In the general effect of the cleaning in the first stage COD Surfactant COD | Surfactant 33.1 14.2 39.6 26.8 36,4 17.6 41.8 27.1 37.8 19.8 42.9 28,4 39.3 22.1 43.1 28.5 39.8 22.3 43.1 28.5 40.1 24.3 43.0 27.8 T a b l 2 The cleaning effect,% of the first stage after electrooxidation; the overall cleaning effect in the second stage mg / mg COD SPAS COD I SPAS 0.54 4.25 25.0 18.2 42.3 38.9 0.8 4.3. 34.0 23,2 65,2 59.6 1,1 4.4 34.6 24.2 79.2 60.0 1,2 4.42 37.0 28,2 79.8 60.8 1,5 5.3 42.0 30.5 81.0 72.0 2.0 5,6 43,4 31.8 84.0 81.0 ’ Table 3 Water quality indicators Source Water after water treatment t · —— · ———————— known method two-stage three-stage treatment treatment Znacho- The effect, Znacho- the effect Znacho- the effect nie. % nie % ’ nie % ' pH 6.8 6.4 - 6.5 - 6.5 - COD, mg / l 932 448 51.9 109.6 88.2 19.8 97.9 SAS, mg / l 62 43 30.6 17,2 72,2 3,1 95.0 Coloring by denia 1: 1080 1:12 98.8 1:10 99 1: 4 99.6 Electrical costs energy, kWh / m ^e - 1,5 0.8 - 1 , 3