KR100369710B1 - A biological treatment process of dye waste water using granulated active carbon as a support material - Google Patents

Abstract

The present invention relates to a method for treating biological dyeing wastewater using particulate activated carbon as a microbial carrier of a biological anaerobic reaction process, and more particularly, in the biological treatment of dyeing wastewater, the first anaerobic tank-second anaerobic tank-aerobic tank Using a three-step biological process, the first anaerobic tank decomposes the organic matter contained in the wastewater to the first, and in the second anaerobic tank using particulate activated carbon as a carrier for anaerobic microorganisms, microorganisms in the activated carbon pores Long-term incubation and accumulation of hardly decomposable materials enable rapid intensive treatment of hardly decomposable materials, and final removal of residual chemical oxygen demand (COD) in aerobic baths, resulting in shorter time compared to conventional biological treatment processes. Not only improve organic decomposition and color removal D. Since the COD removal rate can be significantly increased, the treatment cost is considerably less. Therefore, it is a very economical and efficient microbial carrier and it relates to a method for treating biological dye wastewater using particulate activated carbon.

Description

A biological treatment process of dye waste water using granulated active carbon as a support material}

The present invention relates to a method for treating biological dyeing wastewater using particulate activated carbon as a microbial carrier of a biological anaerobic reaction process, and more particularly, in the biological treatment of dyeing wastewater, the first anaerobic tank-second anaerobic tank-aerobic tank Using a three-step biological process, the first anaerobic tank decomposes the organic matter contained in the wastewater to the first, and in the second anaerobic tank using particulate activated carbon as a carrier for anaerobic microorganisms, microorganisms in the activated carbon pores Long-term incubation and accumulation of hardly decomposable materials enable rapid intensive treatment of hardly decomposable materials, and final removal of residual chemical oxygen demand (COD) in aerobic baths, resulting in shorter time compared to conventional biological treatment processes. Not only improve organic decomposition and color removal D. Since the COD removal rate can be significantly increased, the treatment cost is considerably less. Therefore, it is a very economical and efficient microbial carrier and it relates to a method for treating biological dye wastewater using particulate activated carbon.

Several methods have been developed to treat dyed wastewater. However, dyeing wastewater contains pigmented compounds such as dyes and hard-decomposable substances such as dyeing agents such as PVA, synthetic detergents, and scavenger, and the wastewater has high temperature (about 40 ℃) and strong alkalinity, which requires a lot of treatment cost. In general, wastewater containing different kinds of dyes is generated irregularly or mixed, which is difficult to treat and low in efficiency. For example, in the complex process leading to physicochemical pretreatment and biological treatment such as flocculation sedimentation and neutralization, which are currently used in most dyeing wastewater treatment, a large amount of solids are generated due to flocculation sedimentation and neutralization, and the treatment thereof is excessively expensive. In addition, there is a limitation in the treatment efficiency, and the removal rate of pollutants and colors is low, so additional treatment is required to additionally use physical or chemical treatments, which is an additional cost burden.

As another method, a biological treatment method using a combination of anaerobic and aerobic treatments to treat dyed wastewater is also used. The principle of the biological process is that due to the reducing atmosphere that is formed in the anaerobic reactor, the macromolecules such as pigments and sludges in the wastewater are decomposed into low-molecular substances to remove chromaticity and some COD components, and then biologically oxidize the remaining residues in the aerobic reactor. To get rid of it. However, in the biological anaerobic treatment process used so far, the growth rate and reaction rate of the microorganisms are slow, so that the microorganisms are generally recycled to the reactor or the carriers such as polyurethane are used to allow the microorganisms to stay in the reactor for a long time. However, the carriers used in the prior art do not satisfy the conditions that the hardly decomposable substances such as dyes contained in the dyeing wastewater do not affect the residence time in the biological anaerobic reactor and are sufficiently decomposed.

As such, most of the dye wastewater cannot be sufficiently decomposed during the residence period through the reactor due to the above problems and the problem of being hardly decomposable. As a result, high removal efficiency cannot be expected in spite of the retention period of about 7 days. Since most physical and chemical treatments are required after biological treatment, the operation cost is excessively increased due to the cost burden used for drugs and auxiliary materials. have. In addition, if you want to treat only biological methods, a long residence time of about 30 days is required, which requires a lot of time and investment cost for the construction of a huge bioreactor.

Therefore, the inventors of the present invention have a strong economic and efficient technique in treating dyeing wastewater in order to solve the problem that wastewater treatment efficiency is low despite the long term treatment period in the conventional biological process and is uneconomical due to excessive operation and investment costs. As required, research efforts have been made from various points of view.

As a result, a biological process consisting of three stages of the first anaerobic tank, the second anaerobic tank, and the aerobic tank is used, and the second anaerobic tank physically adsorbs organic substances and chromatic components in the dye wastewater using particulate activated carbon as a carrier. In this way, the contents of the wastewater stay in the pores of activated carbon for a long time, and the selective growth of microorganisms that decomposes them promotes the decomposition of the hard-decomposable substances in the wastewater, and the treatment time is greatly reduced by maintaining the adsorption power of the activated carbon. The present invention has been completed by finding a way to do this.

Accordingly, an object of the present invention is to provide a method for treating biological dye wastewater using activated carbon as a microbial carrier in a biological anaerobic reactor in order to remove contaminants and color components from dye wastewater very economically and efficiently.

Figure 1 shows a device flow diagram for the treatment of biological dye wastewater using the particulate activated carbon according to the present invention,

Figure 2 shows a conceptual diagram of the material flow change in the pores of the granular activated carbon in the biological treatment method of the dyeing wastewater of the present invention.

[Description of Symbols for Main Parts of Drawing]

10: wastewater inlet 20: pretreatment tank

30: 1st anaerobic reactor 50: 2nd anaerobic reactor

60: aerobic tank 70: discharge tank

55: activated carbon filled layer 21, 31, 33, 51, 61: transfer pipe

22, 32: transfer pump 56, 62: air supply pipe

57: water supply pipe

The present invention comprises the steps of adjusting the pH in the range of 6.5 to 10.5 by introducing the dye wastewater into the pretreatment tank 20 through the wastewater inlet (10);

The pH is adjusted to remove the solids contained in the dyeing wastewater through the transfer pipe 21 and the transfer pump 22 to the first anaerobic reaction tank (30) operated in an upflow to separate the organic matter 1 Secondary wastewater treatment step;

Activated carbon filling layer 55 in which microorganisms in the activated carbon pores are propagated using the activated carbon as a carrier through the primary treatment wastewater through a transfer pipe 33, and an air supply pipe 56 and water in the lower part of the reaction tank. A second wastewater treatment step of decomposing organic matter remaining in the first wastewater and removing chromaticity components by passing through a second anaerobic reactor having a feed pipe 57; And

The secondary treated wastewater is passed through the aerobic reaction tank 60 to the final treatment of the remaining COD components, and passed through the discharge tank 70, characterized in that the treatment method of biological dyeing wastewater consisting of.

The present invention will be described in more detail as follows.

The present invention uses particulate activated carbon as a carrier for biological anaerobic processes based on the basic principle that contaminants contained in dyeing wastewater can be biologically decomposed. The biological treatment that allows two steps is the key feature.

In the case of the conventional biological method, hardly degradable substances such as pigments and good substances contained in the dye wastewater can be decomposed under anaerobic conditions, but are dispersed in water due to the slow growth and reaction rate of microorganisms, which is a major disadvantage of the anaerobic process. Contaminants were only very limitedly captured by anaerobic microorganisms, resulting in poor removal rates.

On the contrary, in the present invention, the anaerobic reaction tank is subjected to the first and second stages so that the contaminants contained in the dye wastewater are first sufficiently removed, and in particular, the secondary anaerobic reaction tank allows the growth of anaerobic microorganisms and the easy capture of hardly degradable substances. It is characterized by using activated carbon having a particle shape as a microbial carrier instead of other carriers such as polyurethane.

That is, the present invention provides an environment in which an anaerobic microorganism in the reaction tank is inhabited in the pores of activated carbon for a long time by installing an activated carbon-filled layer filled with activated carbon in a secondary anaerobic reactor, and the hardly decomposable substance is trapped in the activated carbon so as to stay in the reactor for a long time. It is to make it. Therefore, when the activated carbon is used as a carrier of the anaerobic microorganisms so that contaminants are adsorbed on the activated carbon, the contaminants adsorbed on the activated carbon are in contact with the anaerobic microorganisms inhabiting the pores of the activated carbon for a long time, thereby decomposing the corresponding substances in the activated carbon pores. Selective proliferation of anaerobic microorganisms is possible, and consequently, hardly decomposable substances such as pigments can be easily decomposed.

Conventionally, Korean Patent Application No. 97-69244 discloses a method of using activated carbon as a microbial carrier. In the above method, the activated carbon is regenerated from the activated carbon adsorption column through the waste activated carbon regeneration furnace, and the by-product coal is collected and washed with washing water, and then activated charcoal in the activated sludge is added to the aeration tank of the activated sludge process to treat the wastewater. It describes a method for improving the wastewater treatment efficiency of the activated sludge process.

However, the present invention shows the following fundamental differences in form and function of the activated carbon to be used compared to the prior art method using the conventional activated carbon.

First, in this process, pulverized coal used in the prior art cannot be used, and granular activated carbon of at least 1 mm should be used. The reason for this is that, when pulverized coal is used, due to the temperature conditions of the anaerobic process, which must be maintained at about 30 ° C., the gas present in the pores expands and, as a result, pulverized coal floats and is lost out of the reactor.

Second, in the prior art, the main purpose of using pulverized coal as a carrier is to allow aerobic microorganisms to adhere to the surface of pulverized coal, which means that the supply of oxygen, which is essential for microorganisms in aerobic processes, can be made smoothly only on the surface of pulverized coal. Because. In conclusion, in the prior art, only microorganisms attached to the surface of pulverized coal are meaningful. On the contrary, in the present invention, the anaerobic microorganisms that do not require oxygen live in the pores instead of the surface of the activated carbon, and the activated carbon has the property of adsorbing materials having a relatively high molecular weight. That is, hardly degradable substances present in dyeing wastewater, such as pigments and glues, have a high molecular weight and are easily adsorbed by activated carbon and accumulate in pores, so they are in close contact with the anaerobic microorganisms that live there for a long time and are in contact with hardly degradable substances. The degradability of anaerobic microorganisms is gradually enhanced by adaptation, and consequently, they can be quickly decomposed.

The biological treatment method of the dyeing wastewater using particulate activated carbon as the microbial carrier of the biological anaerobic process according to the present invention will be described in detail with reference to the accompanying drawings.

1 shows a schematic configuration diagram of a dye wastewater treatment process for a preferred embodiment that can be envisioned to realize the dye wastewater treatment method of the present invention.

1, the apparatus for the dyeing wastewater treatment process of the present invention is largely pre-treatment tank 20, the first anaerobic reactor (30), the second anaerobic reactor (50), for adjusting the pH value of the dyeing wastewater, It consists of the aerobic reaction tank 60 and the discharge tank 70.

Specifically, between the pretreatment tank 20 and the first anaerobic reaction tank 30 is equipped with a transfer pipe 21 for transferring the dyeing wastewater adjusted pH value and a transfer pump 22 for quantitatively transferring the wastewater. Between the first anaerobic reactor 30 and the second anaerobic reactor 50, the transfer pipe 33 for transferring the effluent of the primary anaerobic reactor 30 to the secondary anaerobic reactor 50 filled with activated carbon is installed. In addition, a transfer pipe 31 and a transfer pump 32 for partially recycling the dyeing wastewater treated in the first anaerobic reaction tank 30 are installed. And, in order to process the residual material contained in the dyeing wastewater treated in the secondary anaerobic reaction tank 50 is installed to transfer to the aerobic reaction tank 60 through the transfer pipe 51, which is discharged from the aerobic reaction tank 60 The purified water is installed to be discharged through the transfer pipe 61 or flowed out into the discharge tank 70 for temporarily storing for reuse purposes.

In particular, as described above, the secondary anaerobic reactor 50 is a carrier for the anaerobic microorganism to inhabit the inside of the reactor is equipped with an activated carbon filling layer 55, the lower portion of the secondary anaerobic reactor 50 air supply pipe 56 and a water supply pipe 57 are provided to supply air and water as needed to clean the activated carbon filled layer.

Referring to the method of biologically treating the dyeing wastewater using activated carbon as a microbial carrier according to the device process diagram as follows.

First, the present invention performs a process of passing the pre-treatment tank 20 to adjust the pH value in the range of 6.5 to 10.5 to enable biological treatment of the dye wastewater in the anaerobic process.

The next step is a process of biologically performing the first wastewater treatment by performing a process of transferring the pH-controlled wastewater to the first anaerobic reactor 30 through the transfer pipe 21 and the transfer pump 22.

In the first anaerobic reactor according to the present invention (30) is to be operated in an upflow so that the solids generated during the bioreaction process, such as sediment and anaerobic microorganisms can be contained in the dyeing wastewater after pretreatment, in this process Contaminants such as pigments and materials are decomposed first.

In the next step, the wastewater discharged from the first anaerobic reactor 30 is transferred to the second anaerobic reactor 50 through a transfer pipe 33 to decompose the organic matter remaining in the waste water. Wastewater treatment At this time, a part of the dye wastewater flowing out of the first anaerobic reaction tank 30 is recycled to the first anaerobic reaction tank 30 through the transfer pipe 31 and the transfer pump 32 as necessary.

In particular, the inside of the secondary anaerobic reaction tank 50 is provided with an activated carbon filled layer 55 filled with granular activated carbon having a diameter and length of at least 1 mm. In addition, in the lower part of the secondary anaerobic reactor 50, an air supply pipe 56 and a water supply tube 57 are installed to remove the solids from the packed bed when the solids are accumulated in the activated charcoal packed bed 55. Air and water at the same time to the 50 or separately supplied to each to clean the activated carbon filling layer 55 installed on the top.

In other words, the process is the most essential part of the process to be presented in the present invention, in the accompanying drawings Figure 2 conceptually shows the material flow change in the pore of the activated carbon. According to the present invention, as described above, after the adsorption characteristic of activated carbon is preferred, adsorption of a substance having a high molecular weight, pigmented substances contained in the dyeing wastewater and a hardly decomposable substance, such as a gelling agent, are accumulated in the pores and then selectively decomposed. It is decomposed by anaerobic microorganisms that are acclimatized so that the adsorption capacity of activated carbon is regenerated repeatedly.

That is, in step (a) of FIG. 2, when contaminants are introduced into the initial activated carbon, in step (b), the contaminants are adsorbed in the pores of activated carbon, and in step (c), the adsorbed contaminants are saturated and decomposed. In the step (d), the pollutants are completely decomposed to regenerate the adsorption power of the activated carbon, and the decomposed microorganisms are hermetically cleaned in the step (b), so that all the purification processes are repeated again.

Therefore, contaminants such as pigment components contained in the dyeing wastewater introduced into the secondary anaerobic reactor 50 are removed again by physical adsorption and biological decomposition while passing through the activated carbon filling layer 55.

The final step is to pass the second treated wastewater through the aerobic reactor 60 to finally process the remaining COD components and to pass the final treated water to the discharge tank 70, thereby to dye the wastewater according to the present invention The biological treatment process of is completed.

At this time, the aerobic reaction tank 60 used in the present invention may be a general activated sludge method or a fixed phase.

As described above, in the method for treating biological dye wastewater according to the present invention, by using activated carbon as a carrier, not only the retention time of the microorganisms in the reactor, but also the retention time of the hardly decomposable substance is greatly increased, thereby making selective growth of the microorganisms in the activated carbon pores. Through this, the decomposition of the hardly decomposable substance in the pores is promoted, so that the dyeing wastewater satisfies the effluent water quality standard even with a residence time of about 1 day as the adsorption power is maintained, thereby providing a very economical and efficient treatment method of the dyeing wastewater.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited by Examples.

Example 1

Dye wastewater with a COD of 1,850 ppm and an absorbance of 14.60 was treated using the biological treatment device according to the invention shown in FIG. At this time, the activated carbon filling layer of the secondary anaerobic tank was filled with activated carbon having a particle shape having a diameter and a length of 1 mm. The absorbance in the visible light region showing the COD and chromaticity of the treated water was measured by a conventional method, and the results are shown in Table 1 below.

Example 2

Stained wastewater with a COD of 920 ppm and an absorbance of 56.17 was treated using the biological treatment device according to the invention shown in FIG. At this time, the activated carbon filling layer of the secondary anaerobic tank was filled with activated carbon having a particle shape having a diameter and a length of 1 mm. The absorbance in the visible light region showing the COD and chromaticity of the treated water was measured by a conventional method, and the results are shown in Table 1 below.

Comparative Examples 1-2

Treated with the same dyeing wastewater as in Example 1, but treated without using activated carbon in the secondary anaerobic reactor in the treatment apparatus, the absorbance in the visible region showing the COD and chromaticity for the treated water treated in a conventional manner The results are shown in Table 1 below.

Comparative Example 3

Treated with the same dyeing wastewater as in Example 1, but treated using a polyurethane conventionally used in the secondary anaerobic reactor in the treatment apparatus as a microbial carrier, a spine showing the COD and chromaticity for the treated water treated in a conventional manner The absorbance in the light ray region was measured and the results are shown in Table 1 below.

Comparative Example 4

Treated with the same dyeing wastewater as in Example 1, but was treated in the order of flocculation sedimentation-neutralization-biological aerobic treatment-sodium hypochlorite under conditions in which the total treatment time used in the prior art is longer, and treated in a conventional manner. The absorbance in the visible light region indicating the COD and chromaticity for water was measured and the results are shown in Table 1 below.

As described in detail above, in the biological treatment method of dyed wastewater using particulate activated carbon as a microbial carrier of the biological anaerobic process according to the present invention, by using activated carbon as a microbial carrier, despite the long treatment time in the existing biological treatment process Unlike the low removal rate of pollutants such as color, the biological treatment alone can show excellent treatment efficiency within a short time, and it is possible to treat the dyeing wastewater in a very economical and rapid manner.

Claims (4)

Adjusting the pH to a range of 6.5 to 10.5 by introducing the dye wastewater into the pretreatment tank 20 through the wastewater inlet 10; The pH is adjusted to remove the solids contained in the dyeing wastewater through the transfer pipe 21 and the transfer pump 22 to the first anaerobic reaction tank (30) operated in an upflow to separate the organic matter 1 Secondary wastewater treatment step; Activated carbon filling layer 55 in which microorganisms in the activated carbon pores are propagated using the activated carbon as a carrier through the primary treatment wastewater through a transfer pipe 33, and an air supply pipe 56 and water in the lower part of the reaction tank. A second wastewater treatment step of decomposing organic matter remaining in the first wastewater and removing chromaticity components by passing through a second anaerobic reactor having a feed pipe 57; And Particulate activated carbon as a microbial carrier of a biological anaerobic process, comprising the step of passing the secondary treated wastewater through the aerobic reaction tank 60 to the final treatment of the remaining COD components, and passing through the discharge tank 70 for treatment. Biological dye wastewater treatment method using. The method of claim 1, wherein the activated carbon filling layer 55 used as the microbial carrier is filled with activated carbon having a diameter and a length of at least 1 mm particulate activated carbon as a biological carrier of the biological anaerobic process, the biological dye using the granular activated carbon Waste water treatment method. The microorganism carrier of the biological anaerobic process according to claim 1, wherein the air supply pipe (56) and the water supply pipe (57) are supplied with air and water at the same time or separately supplied to wash the activated carbon filling layer (55). Treatment method of biological dye wastewater using particulate activated carbon as a method. The method of claim 1, wherein a part of the effluent discharged from the first anaerobic reactor 30 after the first wastewater treatment step is recycled to the primary anaerobic reactor 30 through the transfer pipe 31 and the transfer pump 32 A method of treating biological dyed wastewater using particulate activated carbon as a microbial carrier of a biological anaerobic process.