SU1296517A1 - Method for purifying stratal and drainage water of sulfur pits - Google Patents

Abstract

The invention relates to methods of treating wastewater containing hydrogen sulphide, carbon dioxide, mechanical impurities, and dissolved calcium and magnesium salts, and can be used in the mining and chemical industry, in particular, for manufacturing; sulfur, as well as in the gas, chemical, petrochemical industry. The purpose of the invention is the creation of drainless water purification technology while reducing the consumption of reagents for the treatment and use of purified water as a heat carrier that meets the optimal conditions for underground smelting of sulfur. The method involves the removal of suspended substances by a hydroacoustic method and the subsequent electro-chemical treatment of water with separation into two streams: catholyte, from which calcium carbonate and magnesium carbonate crystals are removed, and anolyte, from which desorption of CO, as well as anion exchange method is removed by an ion-exchange method. A portion of the katolite is sequentially used to regenerate the anionite filter and wash the sand filter and then used as an absorption solution for air purification from HjS, after which the spent solution is mixed with the condensed hydroacoustic filter product and centrifuged. The air after purification by the absorption solution is mixed with the catholyte and directed again for stripping and COg from the anolyte. The separated sediment is sent to the dump, and the purified anolyte is mixed with the catholyte after it has been processed and sent to prepare a heat carrier for underground smelting of sulfur. 1 or 2 tab. "L with you about 05 joint venture

Description

The invention relates to the treatment of wastewater from sulfur enterprises, namely the removal of hydrogen sulphide, carbon dioxide, mechanical impurities and dissolved calcium salts and magnes, and can be used in the mining and chemical industry, particularly in the production of sulfur by the method of underground smelting, as well as in the gas, chemical, petrochemical and other industries of the industry.

The purpose of the invention is the creation of drainless water purification technology while reducing the consumption of reagents for processing and the use of purified water as a heat carrier for underground smelting of sulfur.

The drawing shows the implementation of the proposed method.

The source water 1 is directed to a hydroacoustic filter 2, which removes mechanical impurities in the form of a condensed product. Purified water 3 is sent to a diaphragm electrolyzer for treatment. Anolyte 5 enters the degasser 6 at the stage of blow-off of dissolved gases and then to the anion-exchange filter 7 at the stage of separation.

laziness of anions and gas-air. the mixture containing hydrogen sulphide and carbon dioxide is fed to the chemical treatment stage to the absorber 8. Catalytic 9 is sent to the mixer 10, to which carbonated air containing hydrogen sulfide is fed to intensify the formation of calcium and magnesium carbonates. Crystal removal

fishing is carried out using a sand filter 11t

Purified water (catholyte) is mixed with water after the anion-exchange filter 7 and directed through conduit 12 to prepare a heat carrier for underground sulfur melting. A portion of the purified water after the filter 11 is used to regenerate the anionite filter. The waste regeneration solution is fed to the washing of the sand filter mixed with calcium and magnesium carbonates used in the chemical treatment stage of the gas-air mixture 8, the treated solution 13 after the absorber 8 together with the condensed product sent to centrifuge 14 for mechanical sludge dewatering.

0

five

0

five

0

five

The precipitate is sent to the dump, and the separated liquid (fugat) 15 is mixed with the initial water and purified.

The isolated purified air after the stage of mixing catholyte with the gas-air mixture 10 is directed in a closed loop to the stage of stripping.

The use of a hydroacoustic method for removing suspended impurities allows the source water to be purified without the use of reagents. In addition to this, there is no bulky equipment (sumps, filters) used to implement this method.

The electrochemical treatment of water in a diaphragm-free electrolyzer reduces the costs for desorption of gases (H, S and CO,) from the anolyte, due to the absence of acid used for acidification, and for purification of SO anions, since

only half of the total flow is exposed. Accordingly, the cost of cleaning the second part (catholyte), which is only filtered, is reduced.

In addition, the separation of the treated water into anolyte and catholyte allows the use of catholyte (silk solution with a pH of 10-11 for the regeneration of the anion-exchange filter and the subsequent washing of the sand filter. Then this solution is used as an absorption solution at the stage of chemical processing, as it contains in it the manure is a hydrogen sulfide sorbent, which makes it possible to increase the efficiency of the process by eliminating the consumption of reagents and utilizing the brines resulting from the treatment of water.

Mixing exhaust air with catholyte provides intensive growth of limestone crystals due to the reaction between the Ca, and cations. SOU in an alkaline medium, and its subsequent direction to the degasser at the anolyte stage of stripping from K, 3 and CO, makes it possible to create a closed loop for the movement of air depleted in oxygen, which leads respectively. to the inhibition of biochemical processes in the degassing cycle and, therefore, prevents the growth of desorption apparatuses,

Mixing the spent absorption solution with condensed pro312

using a sonar filter and subsequent centrifuging of the mixture improves the dehumidification process due to the presence of lime and provides a cemented agglomerate resistant to external influences.

The use of the proposed sequence of operations allows creating a drainless and efficient wastewater treatment method, which provides a sufficiently high degree of purification for subsequent discharge to surface sources and subsequent use in order to prepare a coolant for underground sulfur melting from cold water drainage water (water temperature less than 100 ° C).

Example 1. The initial drainage water, which is the drain of serodavocation quarries and is intended for dp discharge into surface water sources, is subjected to purification according to the proposed method.

The results of the analyzes are given in table. one.

A similar treatment was carried out with the reservoir water, which contains in its composition harmful impurities, mg / l suspended solids up to 300J hydrogen sulfide up to 600; ions and pH-7.9, temperature

After treatment, the composition of water is as follows: no suspended solids, no sulfur, no Ca, 22 mg / l and 80, - 115 mg / l, pH - 6.6; temperature 64 C.

As can be seen from the above data, the composition of the purified water satisfies the requirements for discharge into surface sources or for the preparation of a heating medium.

Example 2. In order to determine the effectiveness of water purification from hydrogen sulphide and carbon dioxide, investigations were conducted both on a closed air cycle and on an open air circuit at various flow rates of the latter. The results of the formation water tests are given in Table. 2

Similar results are obtained with a closed air circulation system. However, the temperature of the water with closed and open air cycles differs significantly. With a closed circuit, the temperature of the treated water is 64 ° C, and with fresh air supply it is 30-34 C.

74

Therefore, a circuit with a closed air system is more economical to prepare a heat carrier.

In comparison with the known method, the proposed method allows creating drainless drainage and formation water purification technology to meet the requirements, allowing them to be discharged into surface sources or used to prepare a heat transfer medium for underground smelting. The method also allows refusing the use of reagents, eliminating the discharge of concentrated brines or regeneration solutions, and saving the energy used to heat the purified water for the preparation of a heating medium.

Formula of invention

The method of purification of reservoir and drainage waters of sulfur extraction quarries, including the separation of suspended and colloidal impurities, the stage of blowing hydrogen sulfide with air and the subsequent chemical treatment of the gas-air mixture, the purification of purified air, the electrochemical treatment of water, anion exchange filtering and regeneration of the anion exchanger, different from the fact that, in order to create drainless water treatment technology while reducing the consumption of reagents for processing and using purified water as a heat carrier for underground smelting After separation of suspended and colloidal impurities by a hydroacoustic method in the form of a condensed product and electrochemical treatment of clarified water in a diaphragm electrolyzer, the anolyte is directed to the stage of blowing off hydrogen sulfide with air and subjected to anion exchange filtering, and the catoli are mixed with a gas-air mixture passing through a chemical stage. after the precipitation of calcium and magnesium carbonates on the sand filter is combined with a stream of purified anolyte and used to prepare a heat carrier, When in use, part of the purified catholyte is fed to the regeneration of the anion exchanger, and the spent solution is regenerated diet fed for washing sand filter and in admixture with karbo5 1296517 6

With calcium and magnesium, the precipitate is sent to the dump, the furate is a change in the chemical treatment stage, gas is mixed with the source water, and the air mixture is mixed, after which the mixed purified air after the stage of wagons with the condensed product and catholyte mixed with the air-gas is mixed. centrifuging, with the mixture being sent to the stripping stage.

Table

Eveshenny substances, mg / l

150

Hjs

Sa

SO

-

nso

PH

AO

Aoo

800

500

8.2

24 JSC AOO 800

8.2

2A

750 800 500 10.3

2A AO 50 800 8 A.1

Desorber H, S

COj Absorber

"/ CO

Mixer

50 30

A, 2

20 1АО

10.3

65,160

6.7

30 25

About 22

24 20

1 19

20 17

с1 17

SI

1296517

Editor I. Segl nick

Compiled by V. Vilinska

Tehred V. KadarKorrektor I. Muska

Order 710/25 Circulation 852

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

tr

: F

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Claims (1)

Claim A method for treating formation and drainage waters of sulfur mining quarries, including separating suspended and colloidal impurities, a stage of blowing hydrogen sulfide with air and subsequent chemical treatment of the air-gas mixture, purifying air, electrochemical treatment of water, anion exchange filtering and regeneration of anion exchange resin, characterized in that, in order to create non-closed water treatment technology while reducing the consumption of reagents for the treatment and use of purified water as a coolant for underground smelting of sulfur, after the hydroacoustic method separates suspended and colloidal impurities in the form of a condensed product and electrochemical treatment of clarified water in a diaphragm electrolyzer, the anolyte is sent to the stage of hydrogen sulfide blow-off with air and subjected to anion-exchange filtering, and the catholyte is mixed with a gas-air mixture that has undergone a chemical treatment stage, and after carbonates are separated from it calcium and magnesium on a sand filter are combined with a stream of purified anolyte and used to prepare a coolant, moreover, an hour The purified catholyte is directed to regeneration of the anion exchange resin, and the spent regeneration solution is fed to washing the sand filter and mixed with calcium and magnesium carbonates at the stage of chemical treatment of the gas-air mixture, then mixed with the condensed product and subjected to centrifugation, while the precipitate is sent to the dump , the centrate is mixed with the source water, and the separated purified air after the stage of mixing the catholyte with the gas-air mixture is sent to the stage of blowing. Table 1 The composition of the original Composition ate water e processing in stages Cleared water, mg / l Hydro- Electrochemical Desor Anion Sandy acoustics apparatus b era exchange filter filter catholyte | anolyte filter Suspended matter mg / l 150 24 24 24 24 - - - H _t s 40 40 - 40 3 - - Sa ^a * ' 400 400 750 fifty fifty fifty 20 65 SO * 800 800 800 800 800 thirty 140 160 nso; 500 - 500 Z8 - - - pH 8.2 8.2 10.3 4.1 4.2 4.2 10.3 6.7 table 2 The concentration of dissolved gases, mg / l The amount of air, m ³ / m ³ fifteen I ² "I 25 I 30 Desorber H ₂ s 40 thirty 24 20 from ₂ 34 25 20 17 Absorber v <7 <3 <1 <1 with thirty 22 19 17 Mixer from ₂ 9 7 6 6