KR100647011B1 - A dyeing wasrewater processing method using a powered coke - Google Patents

Abstract

A method for treating dyeing waste water by using coke breeze is provided to easily separate a solid and a liquid of dyeing waste water within a short time by effectively absorbing and separating a pollutant of dyeing waste water by using coke breeze, thereby reducing the size of a sedimentation tank. Floc is generated by mixing and agitating dyeing waste water and polymer coagulant in a first mixing tank(1a). The dyeing waste water is transferred to a flotation separating tank(2) and compressed air is sprayed from a lower part of the flotation separating tank for floating the floc to collect the floc. The dyeing waste water is transferred to a second mixing tank(1b) and coke breeze having a specific gravity of 1.9-2.4 is mixed with the dyeing waste water to absorb non-collected floc. The dyeing waste water is transferred to a third mixing tank(1c) and a polymer coagulant is mixed with the dyeing waste water to coagulate floc absorbing matters into a solid. The dyeing waste water is transferred to a sedimentation tank(3) for sedimenting and separating the solid to discharge purified dyeing waste water.

Description

A dyeing wasrewater processing method using a powered coke}

1 is a dye wastewater treatment flow chart of the present invention

* Explanation of symbols for the main parts of the drawings

1: Mixing tank (a, b, c) 2: Floating separation tank

3: settling tank 4: compressed air generator

5: skimmer 6: polymer coagulant input device (a, b)

7: powder coke feeding device 8: agitator (a, b, c)

9: dehydrator (a, b)

The present invention comprises the steps of mixing and stirring the dyeing wastewater and the polymer coagulant first in the first mixing tank to form a floc (Floc), by transferring the dyeing wastewater to the flotation separation tank and injecting compressed air from the bottom of the flotation separation tank Floating the flocs to collect them, conveying the dyed wastewater to the second mixing tank and mixing and stirring the powdered coke to adsorb the uncollected flocs, transferring the dyed wastewater to the third mixing tank and transferring the floc adsorbate to the solids Mixing and stirring the polymer coagulant secondly to agglomerate, and transferring the dyeing wastewater to the settling tank for precipitating and separating the solids and discharging the purified dyeing wastewater, which is inexpensive and has a high specific gravity and specific surface area. As coke is used to effectively adsorb contaminants to separate and collect, solid / liquid separation of dyeing wastewater can be easily performed in a short time. It relates to dyeing wastewater treatment methods can do.

Dyeing industry is an essential industrial field for human life, and it is an industry that uses dye as a raw material to express color through physical and chemical reactions to the salt, and is one of the industries that emit the most pollutants.

However, in order to cope with international environmental regulations, dyeing and processing techniques that reduce water consumption are actively developed, and relatively high concentrations of wastewater are discharged. According to a recent report, the average water quality of the wastewater flowing into the joint wastewater treatment plant of a dyeing industrial complex in Korea for 4 years was BOD ₅ 1,387 mg / L, COD _Mn 658 mg / L, SS 72 mg / L, and color 965 ( FIG. 6), TN 41.2 mg / L, TP 6.51 mg / L, normal hexane 12.33 mg / L and ABS 86.5 mg / L. The high concentration of the dye wastewater is highly contaminated and difficult to treat. Therefore, many techniques have been developed for treating such high concentration dyeing wastewater. These techniques are known as BOD ₅ as flocculants. It is largely divided into removing components, removing suspended substances and oils by passing through a filtering device, and treating dyed wastewater using active microorganisms.

Specifically, Korean Patent Publication No. 1993-0013890, "Method of Treating Dyeing Wastewater", after adjusting the pH of dyeing wastewater, performs biological wastewater treatment, and Korean Patent Publication No. 1999-0003750, "Dyeing Wastewater Treatment." Treatment method "is to remove the fine suspended matter and the adsorbent material by passing the waste water through the filtration device, and to remove the contaminants in the waste water by passing the separated water through the nanofiltration membrane device, Korean Patent Publication No. 1999-0038487 "Method of Treating Textile Dye Wastewater" discloses treating the waste water by adjusting the pH of the dyeing waste water and then performing active microbial treatment and adding a flocculant.

However, these conventional methods are difficult to separate solid / liquid due to the characteristics of the dye wastewater, the color of the wastewater is increased by the iron chloride added for the solid-liquid separation, and the self-heating amount is reduced when the dehydrated cake is incinerated. There is a problem of being excessive. In particular, the flocculant used in the prior art is difficult to separate the solid / liquid separation of the dyeing wastewater because the specific gravity is not properly settled in the dyeing wastewater, there is a problem that the cost is very high, greatly increasing the treatment cost of the dyeing wastewater.

The present invention provides a method for treating dye wastewater using powdered coke that can easily perform solid / liquid separation of dye wastewater by effectively adsorbing and separating contaminants using powdered coke, which is a fine powder having a specific gravity and a specific surface area. Its purpose is.

Dyeing wastewater treatment method using the powdered coke according to the present invention comprises the steps of mixing and stirring the dyeing wastewater and the polymer coagulant first in the first mixing tank to form a floc (Floc), transfer the dyeing wastewater to the flotation separation tank and the flotation Spraying compressed air from the lower part of the separation tank to float the floc, collecting the floc, transferring the dyed waste water to the second mixing tank, mixing and stirring the powdered coke to adsorb the uncollected flocs, and removing the dyed waste water. 3 mixing and stirring the polymer coagulant secondly to transfer to the mixing tank and aggregate the floc adsorbate into the solids, and the dyeing waste water is transferred to the settling tank to precipitate and separate the solids and discharge the purified dyeing wastewater. There is this.

In addition, the process of transferring the dyeing wastewater from the first mixing tank to the flotation separation tank is carried out for 10 to 30 minutes by gravity.

In addition, the powdered coke applies a CDQ powdered coke.

In addition, flocs floating on the surface of the dyeing wastewater in the flotation separation tank are collected using a skimmer.

The present invention is generated as a by-product in the coke production process, and provides a method for effectively adsorbing and removing contaminants of dye wastewater using powdered coke, which is conventionally recycled only for fuel.

As the coke is produced as a by-product in the coke manufacturing process, it is very inexpensive, has a large specific surface area, which has excellent adsorption capacity, and has a specific gravity of 1.9 to 2.4, which easily sinks in dyeing wastewater and has a very large amount of heat. Fine powder. These coke powders are divided into digester coke powder generated when cooling the coke with water, CDQ powder coke generated when cooling the coke with inert gas, and general coke generated when classifying and handling the finished coke. It is preferable to apply the CDQ powdered coke having the best particle size among the powdered coke.

The density of the powdered coke is disclosed in Table 1 below.

[Table 1] Analysis of specific gravity of buncoke

division Common powder coke Digestive Coke Coke CDQ powder coke importance 2.10 1.94 1.92

In Table 1, the specific gravity of the coke was found to be about 2.0.

The particle size of the coke is disclosed in Table 2 below.

[Table 2] particle size analysis table of the bunk coke

Powdered coke +6 Mm% +3 Mm% +1.4 Mm% +0.5 mm% +0.25 Mm% +0.15 Mm% -0.15 Mm% MS ^* CDQ powder coke - - 0.37 4.75 14.24 18.67 61.96 0.19 Digestive Coke Coke 8.71 6.06 10.03 30.01 24.03 9.60 11.52 1.42

Powdered coke + 50mm% +38 mm% + 25mm% + 15mm% + 10mm% + 6mm% -6mm% MS Common powder coke - - - 11.20 20.60 24.10 - 8.10

(* MS: Average particle size)

As a result of the particle size analysis in Table 2, the particle size of the CDQ powdered coke was found to be the best.

The present invention is described in detail below.

In order to effectively purify the dyeing wastewater by applying a coke having a specific gravity of 1.9 to 2.4, first, a pretreatment step of first treating the dyeing wastewater with a polymer coagulant to aggregate and separate the blocks is performed. The polymer coagulant mixed in the dyeing wastewater is selected from the group consisting of cationic, zwitterionic and anionic systems.

Specifically, the dyeing wastewater is injected into the first mixing tank, and the polymer agglomerate of a certain content is first introduced into the dyeing wastewater and stirred. As described above, when the polymer coagulant and the dye waste water are stirred and mixed, the contaminants contained in the dye waste water and the polymer coagulant react to form flocs. In order to promote the reaction between the contaminants of the dyeing wastewater and the polymer coagulant, the stirrer of the first mixing tank is stirred at a stirring speed of 30 to 120 times / min for 1 to 5 minutes to form a floc.

As described above, the dyeing wastewater in which the floc is formed in the first mixing tank is transferred to the flotation separation tank, and is transported for 10 to 30 minutes by gravity so that the floc is not dispersed in the conveying process. Therefore, the floating separation tank is installed at a lower position than the first mixing tank, and the transfer pipe and the valve connecting the first mixing tank and the floating separation tank are configured to a size suitable for transferring the dyeing waste water over 10 to 30 minutes. .

The flocs are collected by floating them from the dyeing wastewater transferred to the flotation tank as described above. The flocs contained in the dyeing waste water naturally have low specific gravity.

Injuries, however, take up to 30 to 60 minutes to spontaneously injure, so compressed air is blown upwards from the bottom of the flotation tank to shorten the time required for floc injury. That is, a compressed air generating device for providing compressed air to the floating separation tank is formed, and the compressed air droplets blown upward from the diffuser are connected to a diffuser starting from the compressed air generating device connected to the lower portion of the floating separation tank. Push it up to promote injury to the surface of the dye wastewater and injuries in 5 to 10 minutes. Complete the pretreatment step of the dyeing wastewater by rapidly collecting flocs floating and floating on the surface of the dyeing waste water using a skimmer.

The dyeing wastewater pretreated as above is transferred to the second mixing tank, and a predetermined amount of coke is added to the transferred dyeing wastewater and stirred. As described above, when the mixed coke and dyed waste water are stirred and mixed, uncollected flocs of the dyed coke are adsorbed onto the coke particles. The powdered coke has a specific surface area, so the floc is easily adsorbed.Because the specific gravity of the powdered coke is high, the adsorbate of the powdered coke and the floc easily sinks in the dyeing wastewater. It is easy and can carry out.

As described above, the dyeing wastewater in which the adsorbate is formed is transferred to a third mixing tank, and a polymer flocculant having a predetermined content is added to the transferred dyeing wastewater in a second manner and stirred. As described above, when the polymer coagulant and the dye waste water are stirred and mixed, the adsorbate contained in the dye waste water aggregates to the polymer coagulant particles to form a solid.

In order to promote aggregation of the adsorbate and the polymer coagulant particles, the stirrer of the second mixing tank is stirred at a stirring speed of 10 to 50 times / minute for 15 to 20 minutes to form a solid.

Transfer the dyeing wastewater in which the solids are formed to the sedimentation tank as described above, and leave it for 15 to 30 minutes to precipitate solids contained in the dyeing wastewater to separate the solids / liquids, and the solids are removed to discharge the purified dyeing wastewater. To complete the processing. Since the specific gravity of the powdered coke included in the solid is large, the time required for sedimentation of solids, that is, solid / liquid separation of dyeing wastewater is only 15 to 30 minutes, which is drastically shortened compared to the conventional 2 to 4 hours.

The present invention will be described in detail with reference to examples and drawings.

EXAMPLE

Dyeing wastewater is injected into the first mixing tank 1a. The polymer coagulant is first introduced into the injected dye wastewater from the polymer coagulant injector 6a, and the stirrer 8a of the first mixing tank 1a is used to promote the reaction between the pollutant and the polymer coagulant of the dye waste water. Was stirred for 5 minutes at a stirring rate of 90 times / min to form a floc.

Opening the valve of the transfer pipe connecting the first mixing tank 1a and the floating separation tank 2 to lift the dyeing wastewater of the first mixing tank 1a over 30 minutes by gravity. Transfer to.

When the transfer of the dyeing waste water is completed, the compressed air generating device 4 connected to the floating separation tank 2 is operated to inject the compressed air upward from the bottom of the floating separation tank 2. As above, the compressed air droplets injected upwards push the floes and float to the surface of the dye wastewater in 10 minutes. The flocs floating and floating on the surface of the dyeing wastewater are collected quickly using the skimmer 5 to complete the pretreatment step of the dyeing wastewater. The collected flocs are dehydrated by a dehydrator 9a for disposal.

The dyeing wastewater pretreated as above is transferred to the second mixing tank 1b. A constant content of CDQ powdered coke is introduced into the transferred dye wastewater from the powdered coke feeder 7 and stirred with a stirrer 8b. As described above, when the CDQ powdered coke and the dyeing waste water are stirred and mixed, the uncollected flocs of the dyeing waste water are adsorbed onto the CDQ powdered coke particles.

The dye wastewater in which the adsorbate is formed as described above is transferred to the third mixing tank 1c. In order to promote the coagulation of the adsorbate and the polymer coagulant particles, the polymer coagulant is introduced into the transferred dye wastewater from the polymer coagulant injector 6b. The mixture is stirred for 20 minutes to form a solid.

As described above, the dyeing wastewater in which the solid is formed is transferred to the settling tank 3. The transferred dyeing wastewater is left for 30 minutes to precipitate solids contained in the dyeing wastewater and separated into solids / liquids, and the separated solids are dehydrated by a dehydrator 9b for incineration. The solids can be easily incinerated, even with a small amount of fuel, because the solids contain CDQ powdered coke with a very high calorific value.

Solids are precipitated in the settling tank 3 to discharge the purified dyeing wastewater, thereby completing the treatment of the dyeing wastewater.

The dyeing wastewater treatment method according to the present invention can easily carry out solid / liquid separation of dyeing wastewater in a short time by effectively adsorbing and separating contaminants using powdered coke, thereby miniaturizing the sedimentation tank, and dyeing wastewater. Since iron chloride-based chemicals are not used in the treatment, the chromaticity of the treated dye wastewater is improved, and the calorific value of the car body is increased, thereby reducing the cost of incineration.

As described above, the present invention has been described in detail with reference to the described embodiments, but it will be apparent to those skilled in the art that various changes and modifications can be made within the scope and spirit of the present invention. It is also natural to fall within the scope.

Claims (4)

Mixing and stirring the dye wastewater and the polymer coagulant in a mixing tank to form a floc; Transferring the dyeing wastewater to a flotation separation tank and injecting compressed air from the lower portion of the flotation separation tank to collect the flocs by flotation; Mixing and stirring the powdered coke having a specific gravity of 1.9 to 2.4 to transfer the dyeing wastewater to another mixing tank and adsorb uncollected flocs; Mixing and stirring the polymer coagulant secondly to transfer the dyeing wastewater to another mixing tank and to aggregate the floc adsorbate into a solid; Transferring the dyeing wastewater to the settling tank for sedimenting and separating solids and discharging the purified dyeing wastewater; Dyeing wastewater treatment method using a powdered coke characterized in that the configuration. The method of claim 1, wherein the process of transferring the dyeing wastewater from the first mixing tank to the flotation separation tank is configured to be carried out for 10 to 30 minutes by gravity. The method of claim 1, wherein the bunk coke is CDQ bunk coke. The method of claim 1, wherein the flocs floating on the surface of the dye wastewater in the flotation separation tank is configured to be collected using a skimmer.

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