JP4093345B2 - Colored wastewater treatment method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for treating colored wastewater containing a hardly decomposable coloring compound by bacteria. More specifically, the decolorizing method of the present invention is widely used in all technical fields including a decolorizing step of colored wastewater generated in the dye manufacturing industry, the fiber dyeing industry, the paper / pulp dyeing industry, and the like.
[0002]
[Prior art]
Conventionally, colored substances in wastewater are generally hardly biodegradable, and therefore cannot be removed only by biological treatment such as activated sludge. For this reason, aggregation using polyaluminum chloride or ferric chloride is impossible. A precipitation method, a flotation separation method, an adsorption method using activated carbon, or an oxidative decomposition method using sodium hypochlorite or ozone has been used.
However, coagulation sedimentation and flotation separation methods are difficult to treat waste sludge, activated carbon has problems in the process complexity and economics associated with regeneration, and sodium hypochlorite produces all organic halogen compounds (TOX). Safety and ozonation in the world leave doubts on high running costs.
[0003]
Therefore, as a method for solving these problems, a method for decolorizing a dye using bacteria has been studied. Examples of such decolorization methods include decomposition of benzene ring-containing dyes by Nocardia Coralina species (Japanese Patent Laid-Open No. 48-56881), and decomposition of basic dyes by Pseudomonas (Japanese Patent Laid-Open No. 48-82662). ), Decolorization of monoazo, diazo, anthraquinone, triphenylmethane, methine, and monoazo polymer dyes by Alkaligenes (JP-A 63-216472), Bacillus, Xanthomonas, and Achromobacter There is color erasure or reduction of azo dye coloring liquid by each bacterium belonging to the bacterium (Japanese Patent Laid-Open No. 8-261).
As described above, when the dye coloring liquid is processed using bacteria, it can be seen that there is a clear speciality in the relationship between the bacteria and the dye to be processed.
[0004]
[Problems to be solved by the invention]
The problem to be solved by the present invention is to provide a treatment method for decolorizing colored wastewater by adding bacteria having resolution of a hardly decomposable colored compound to colored wastewater, particularly colored wastewater containing at least an azo dye. .
High-concentration colored wastewater discharged from the dye manufacturing industry, fiber dyeing industry, paper / pulp dyeing industry, etc. includes direct dyes, acid dyes, reactive dyes, cationic dyes, sulfur dyes, disperse dyes and the like. Their dye structures are monoazo, disazo, trisazo, tetraazo, metallized azo, formazan, phthalocyanine, and anthraquinone hard-to-decompose compounds, and the discharged colored wastewater is mixed with these compounds. Waste liquid. Of the various dyes currently used, azo dyes occupy about 60 to 70%, and are used in a wide range of technical fields such as fabric dyeing, food dyeing, and paper dyeing. Naturally, a large amount of azo dyes are contained in the waste liquid of these dyes.
[0005]
In addition, the colored wastewater includes dyestuff manufacturing industry, raw materials discharged from the dye industry, intermediate manufacturing by-products, dispersants, solubilizers, surfactants, leveling agents, fixing agents, sizing agents, soaping agents, etc. It is included and complicates problem solving.
That is, there is a demand for a low-cost treatment method using a highly resistant bacterium that decomposes and decolors various dyes and further proliferates even when the above compound is present in wastewater.
[0006]
[Means for Solving the Problems]
As a result of intensive investigations to solve the above-mentioned conventional drawbacks, the present inventor has focused on the fact that specific bacteria decompose and decolorize colored wastewater, in particular, hard-to-decompose colored compounds in colored wastewater containing at least an azo dye. And it discovered that the said objective could be achieved by propagating these predominately in a colored wastewater system, and came to complete this invention based on this knowledge.
[0007]
That is, the present invention relates to the following (1) to (6).
(1) One or more bacteria selected from bacteria belonging to the genus Citrobacter, Morganella, and Enterococcus are added to colored wastewater, pH 7.0-9.5, temperature 20-45 ° C., redox potential ( (Ag / AgCl electrode standard) A method for treating colored wastewater, wherein decolorization is performed under a condition of −30 to −550 mV.
(2) The method for treating colored wastewater according to (1), wherein the bacterium is at least one selected from Citrobacter amaronaticus, Morganella morgani, and Enterococcus casei flavus.
(3) The bacteria are Citrobacter amalonaticus MH-1 (FERM P-18145) strain, Morganella morgani MH-2 (FERM P-18146) strain and Enterococcus casei flavus MH-3 (FERM P- 18147) The method for treating colored wastewater according to (1), which is one or more selected from strains.
[0008]
(4) The processing method according to any one of (1) to (3), wherein the colored wastewater is a colored wastewater containing at least an azo dye.
(5) The processing method according to any one of (1) to (4), wherein the colored wastewater is a highly colored wastewater having a ΣOD6 or higher.
(6) Citrobacter amaronaticus MH-1 (FERM P-18145) strain, Morganella morgani MH-2 (FERM P-18146) strain or Enterococcus casseriflavas MH-3 P-18147) strain.
[0009]
In wastewater containing at least an azo dye applied to the present invention, the azo dye includes various azo dyes, and the basic structure includes various monoazo, disazo, trisazo, tetraazo, and metal-containing azo dyes. An azo dye having a basic structure is included.
[0010]
In the bacterium used in the present invention, bacteria belonging to the genus Citrobacter include, for example, CITROBACTER AMALONATICUS species IFO13547, ATCC25405, ATCC25406, ATCC25407, MH-1 strain (National Institute of Biotechnology, National Institute of Advanced Industrial Science and Technology) FERM P-18145) and the like.
[0011]
(A) Isolation, characterization, and identification of Citrobacter amalonatecus MH-1 strain Among the above, Citrobacter amalonateus MH-1 strain (Biotechnology Institute of Industrial Science and Technology, FERM P) -18145) is a novel strain, for example, isolated from activated sludge (dye production factory) and the bacteriological properties are as follows.
Dilute the sludge sample, smear it on a standard agar medium (manufactured by Nissui Pharmaceutical) containing 250 ppm of CI Reactive Red120, culture it, and catch the colony decolorized from the most highly diluted agar medium grown. Isolated on a standard agar medium. The culture was performed at 28 ° C. for 48 hours. Next, Gram staining of the isolated bacteria was performed, and Gram staining and morphology were observed with a microscope. As biochemical properties, a glucose oxidative fermentation test, a catalase test, an oxidase test, an API 20E, and an API 50CH (released by Biomelieu Bitech Japan) were used to identify the bacteria. As a result, the isolated bacterium was identified as a Gram-negative facultative anaerobic bacterium belonging to the species of Citrobacter amalonatecus. This bacterium was named Citrobacteramalonaticus MH-1 strain, and its properties and identification results are shown in Table 1.
[0012]
Table 1
Test item MH-1 strain morphology Neisseria gonorrhoeae Gram staining negative aerobic growth +
Anaerobic growth ＋
Motility +
Glucose oxidation fermentation Fermentation catarase ＋
Oxidase −
Property test with API 20E [0013]
β-galactosidase +
Arginine dihydrase +
Lysine decarboxylase −
Ornithine decarboxylase +
Sodium citrate assimilation −
Hydrogen sulfide production −
Urea decomposition-
Tryptophan deaminase −
Indole production ＋
Acetoin production −
Gelatin degradation −
Oxidation test glucose +
D-mannitol +
Inosit −
D-sorbitol +
L-rhamnose +
Sucrose +
D-Melbiose +
D-Amygdalin +
L-arabinose +
[0014]
Carbohydrate metabolism test with API 50CH Glycerol-
Erythritol −
D-arabinose +
L-arabinose +
Ribose +
D-xylose +
L-xylose-
Adonitol −
β-methyl D-xyloside −
Galactose +
Glucose +
Fructose +
Mannose +
Sorbose +
Rhamnose +
Dulcitol −
Inositol −
Mannitol +
Sorbitol +
[0015]
α-methyl-D mannoside −
α-methyl-D glycoside +
N acetylglucosamine +
Amygdalin −
Arbutin +
Esclin +
Salicin +
Ceribiose +
Maltose +
Lactose +
Melibiose +
Sucrose +
Trehalose +
Inulin −
Meletetose −
Raffinose +
Starch −
Glycogen −
Xylitol −
Gentibiose +
D-Turanorth +
D-lyxose-
D-Tagatose +
D-Fucose-
L-Fucose +
D-arabitol-
L-arabitol-
Gluconate +
2-ketogluconate +
5-ketogluconate +
[0016]
Next, in the bacterium used in the present invention, as a bacterium belonging to the genus Morganella, for example, Morganella morganii species, IFO 3168, IFO 3848, JCM1672, ATCC 8019, ATCC 8076, ATCC 9237, ATCC 9916, ATCC 23585, ATCC 23585, ATCC 23585, ATCC 23585, ATCC , ATCC 27974, ATCC 27975, ATCC 29853, ATCC 33791, ATCC 35200, ATCC 49992, ATCC 49993, ATCC 49994, MH-2 strain (Institute of Industrial Science and Technology, FERM P-18146) and the like.
[0017]
(B) Isolation, characterization, and identification of Morganella morgani MH-2 strain Among the above, Morganella morgani MH-2 strain (National Institute of Biotechnology, FERM P-18146) ) Is a novel strain, for example, isolated from activated sludge and has the following mycological properties.
Dilute the sludge sample, smear it on a standard agar medium (manufactured by Nissui Pharmaceutical) containing 250 ppm of CI Reactive Red120, culture it, and catch the colony decolorized from the most highly diluted agar medium grown. Isolated on a standard agar medium. The culture was performed at 28 ° C. for 48 hours. Next, Gram staining of the isolated bacteria was performed, and Gram staining and morphology were observed with a microscope. As biochemical properties, a glucose oxidative fermentation test, a catalase test, an oxidase test, an API 20E, and an API 50CH (released by Biomelieu Bitech Japan) were used to identify the bacteria. As a result, the isolated bacterium was identified as a Gram-negative facultative anaerobic bacterium belonging to the species Morganella morganii. This bacterium was named Morganella morganii MH-2 strain, and its properties and identification results are shown in Table 2.
[0018]
Table 2
Test item MH-2 strain form Neisseria gonorrhoeae Gram stain negative aerobic growth +
Anaerobic growth ＋
Motility +
Glucose oxidation fermentation Fermentation catarase ＋
Oxidase −
[0019]
Property test β-galactosidase with API-20E −
Arginine dihydrase −
Lysine decarboxylase −
Ornithine decarboxylase +
Sodium citrate assimilation −
Hydrogen sulfide production −
Urea decomposition +
Tryptophan deaminase +
Indole production ＋
Acetoin production −
Gelatin degradation −
Oxidation test glucose +
D-mannitol-
Inosit −
D-sorbitol-
L-rhamnose-
Sucrose −
D-melbiose-
D-Amygdalin −
L-arabinose-
[0020]
Carbohydrate metabolism test with API 50CH Glycerol +
Erythritol −
D-arabinose-
L-arabinose-
Ribose +
D-xylose-
L-xylose-
Adonitol −
β-methyl D-xyloside −
Galactose +
Glucose +
Fructose +
Mannose +
Sorbose −
Rhamnose −
Dulcitol −
Inositol −
Mannitol +
Sorbitol −
[0021]
α-methyl-D mannoside −
α-methyl-D glycoside −
N acetylglucosamine +
Amygdalin −
Arbutin −
Esculin −
Salicin −
Ceribiose −
Maltose −
Lactose −
Melibiose −
Sucrose-
Trehalose +
Inulin −
Meletetose −
Raffinose −
Starch −
Glycogen −
Xylitol +
Gentibiose −
D-Tulanose-
D-lyxose-
D-Tagatose-
D-Fucose-
L-Fucose-
D-arabitol-
L-arabitol-
Gluconate +
2-ketogluconate −
5-ketogluconate −
[0022]
Next, in the bacterium used in the present invention, examples of bacteria belonging to the genus Enterococcus include, for example, Enterococcus casseriflavas, JCM5657, JCM8716, JCM8723, IFO3531, IFO12225, IFO12256, IFO13138, ATCC12755, ATCC12755, , ATCC12816, ATCC12819, ATCC14432, ATCC14436, ATCC25788, ATCC25789, ATCC49604, ATCC49605, ATCC51328, MH-3 stock (National Institute of Biotechnology, FERM P-18147), etc. It is not something.
[0023]
(C) Isolation, characterization and identification of Enterococcus casseriflavas MH-3 strain Among the above, Enterococcus casseriflavas MH-3 strain (National Institute of Biotechnology, Industrial Technology Institute, FERM) P-18147) is a novel strain, which is isolated from activated sludge, for example, and the bacteriological properties are as follows.
The sludge sample was diluted, smeared on a tryptosoy agar medium (Eiken Chemical Co., Ltd.) containing 250 ppm of CI Reactive Red 120, and the culture was decolorized to isolate the bacteria. Next, after morphological observation and physiological property tests were performed on the isolated bacteria to determine the genus, an identification test was performed using an automatic bacterial test apparatus ATB Expression (bioMerieux sa; Nihon Biomelieu Bitech Co., Ltd.). However, a streptococcal identification kit rapid ID 32 STREP (bioMerieux sa; Nihon Biomeryu Vitec Co., Ltd.) was used for the test. In addition, quinone analysis and measurement of the GC content of intracellular DNA were also performed. As a result, the isolate was identified as a Gram-positive facultative anaerobic bacterium belonging to the species Enterococcus caseiflavas (Bergey's Manual of Detergent Bacteriology, 94, . This bacterium was designated as Enterococcus casseriflavas MH-3 strain. The main properties of the strain are shown in Table 3, and the properties and identification results obtained from the kit are shown in Table 4.
[0024]
Table 3
Test item MH-3 strain morphology Cocci Gram staining positive spore-
Motility +
Attitude toward oxygen Aerated anaerobic catalase −
Produced lactic acid L (+)
Gas production from glucose −
Growth at 10 ° C +
Growth at 45 ° C +
Growth in the presence of 6.5% NaCl +
Growth at pH 9.6 +
Village color tone Yellow main quinoline system Not detected (trace MK-8, MK-7 detected)
GC content of bacterial DNA (mol%) 42
[0025]
Table 4
Test item MH-3 strain arginine dihydrase −
β-glucosidase +
β-galactosidase −
β-glucuronidase −
α-galactosidase −
Alkaline phosphatase −
Acid production Ribose +
Mannitol +
Sorbitol −
Lactose +
Trehalose +
Raffinose −
Formation of acetoin +
Alanine-phenylalanine-
Proline allylamidase −
β-galactosidase +
Pyroglutamate allylamidase +
N-acetyl-β-glucosaminide −
Glucyl-tryptophan allylamidase +
Sodium hippurate hydrolysis-
[0026]
Acid production glycogen −
Pullulan −
Maltose +
Meletetose −
Sucrose +
L-arabinose +
D-arabitol-
Methyl-β-D-glucopyranoside +
Tagatose −
Cyclodextrin −
Glycerol −
β-mannosidase −
Urease −
Formation of yellow pigment +
[0027]
In practicing the present invention, one or more of the bacteria may be added directly to the colored wastewater, or previously cultured cells may be added to the colored wastewater. The culture is not particularly limited, but various carbon sources such as glucose, protein, peptone, yeast extract, meat extract, carbon dioxide sources such as amino acids, ammonium sulfate, sodium nitrate, magnesium sulfate, sodium chloride, potassium phosphate, etc. A medium supplemented with various inorganic salts can be used. The culture is stationary culture at a pH of 7.0 to 9.5 and a temperature of 20 to 45 ° C.
[0028]
When the colored wastewater is decolored using the present invention, the wastewater has a pH of 7.0 to 9.5, a temperature of 20 to 45 ° C., and an oxidation-reduction potential (Ag / AgCl electrode standard) (hereinafter referred to as ORP) is − The setting is performed under the condition of 30 to -550 mV. The condition where the oxidation-reduction potential (Ag / AgCl electrode standard) is −30 to −550 mV indicates the range in which the facultative anaerobic bacteria used in the present invention are decomposed and decolorized. If the wastewater does not meet this setting standard, it can be adjusted as appropriate by aeration or deaeration.
Further, the time required for the treatment with the cells is usually about 6 hours to 1 week.
[0029]
In the present invention, since this strain is facultative anaerobic, it grows without agitation, agitation, and aeration air as in aerobic conditions, and progresses in decomposition and decolorization, which is economically advantageous. is there. Furthermore, in the present invention, the strain may contain raw materials, intermediates, dispersants, solubilizers, surfactants, leveling agents, fixing agents, sizing agents, soaping agents and the like in the colored wastewater. It is possible to decompose and decolorize a hardly decomposable coloring compound such as an azo dye which has proliferated without being inhibited and mixed in the colored wastewater in a complicated manner. In addition, there are many aerobic bacteria in the waste water present in the waste water, but the growth of the aerobic bacteria is advantageous for the growth of the strain of the present invention under the conditions of the oxidation-reduction potential of the present invention described above.
[0030]
Furthermore, the present invention is characterized in that it can be efficiently decolored even if the wastewater is colored at a high concentration. The high-concentration colored wastewater is usually treated as indicating colored wastewater having ΣOD6 or higher, for example. On the other hand, the upper limit is not particularly limited, but usually corresponds to colored wastewater of about ΣOD700 or lower.
In addition, the evaluation method of decomposition | disassembly and decoloring of the coloring compound by the bacteria in this invention was performed according to (SIGMA) OD method (document, pollution and countermeasures vol27 No8 741-745, 1991). Absorbance (Abs.) Was measured with a Hitachi spectrophotometer U-3200.
Coloration degree (ΣOD) = sum of specific wavelength OD values (absorbance) of wastewater = (400 nm) + (450 nm) + (500 nm) + (550 nm) + (600 nm) + (650 nm)
Decolorization rate% = (1−ΣOD of treated wastewater ÷ ΣOD of treated wastewater) × 100
For example, ΣOD60 corresponds to 33400 highly colored wastewater in terms of the degree of coloring according to the dilution method (reference PPM vol. 21 No. 2, 8-12, 1990).
[0031]
【Example】
Next, the present invention will be described more specifically with reference to test examples and examples, but the present invention is not limited to these examples.
Test Example 1 Decolorization Ability of Azo Dye of Strains The presence or absence of azo dye decolorization ability of Citrobacter amaronaticus MH-1 strain, Morganella morgani MH-2 strain and Enterococcus caseiflavus MH-3 strain used in the present invention It was measured.
The test method was to add 250 ppm of azo dye (CI Reactive Red 120) to a standard agar medium (manufactured by Nissui Pharmaceutical Co., Ltd.), smear the above three strains, and let stand at 28 ° C. for 48 hours. Later, the condition was observed.
As a result, it was confirmed that all three strains have the ability to decolorize azo dyes.
[0032]
Example 1
A 300 ml Erlenmeyer flask was charged with 100 ml of a medium containing 1.5% tryptone, 0.5% soy peptone, 0.5% sodium chloride, 0.1% lecithin, and 0.7% polysorbate. Enterococcus katseriflavus MH-3 strain (FERM p-18147) was inoculated with one platinum ear and statically cultured at 36 ° C. for 48 hours.
300 ml of colored waste water A (including azo dye factory waste water and other dye factory waste water) was placed in a 500 ml Erlenmeyer flask, and 20 ml (2.5 × 10 ⁸ cfu / ml) of the above culture solution was added (ΣOD149). .2). Subsequently, it left still for 48 hours by pH8.5, temperature 36 degreeC, and ORP-110mV. The ΣOD after the treatment was 15.2, and the decolorization rate was (1-15.2 / 149.2) × 100 = 89.8%. FIG. 1 shows a full curve of absorbance (Abs.) Before treatment and absorbance after treatment at an absorption wavelength of 400 to 650 nm.
[0033]
Example 2
One platinum loop of Enterococcus katseriflavus JCM8723 strain was inoculated on the same medium as in Example 1 and statically cultured at 30 ° C. for 48 hours.
300 ml of colored waste water B (including azo dye factory waste water and other dye factory waste water) was placed in a 500 ml Erlenmeyer flask, and 20 ml of the culture solution (2.0 × 10 ⁸ cfu / ml) was added (ΣOD155). .2). Subsequently, it left still for 48 hours by pH7.5, temperature 30 degreeC, and ORP-45mV. The ΣOD after the treatment was 18.0, and the decolorization rate was (1-18.0 / 155.2) × 100 = 88.4%. FIG. 2 shows a full curve of absorbance before treatment and absorbance after treatment at an absorption wavelength of 400 to 650 nm.
[0034]
Example 3
A 300 ml Erlenmeyer flask was charged with 100 ml of a medium containing 0.7% of meat extract, 1.0% of peptone and 0.3% of sodium chloride, sterilized by a conventional method, and then Morganella morgani MH-2 strain (FERM p-18146). ) Was inoculated with one platinum ear and statically cultured at 27 ° C. for 48 hours.
Colored waste water C (including azo dye factory waste water and other dye factory waste water) 300 ml is put into a 500 ml Erlenmeyer flask, and 10 ml (1.5 × 10 ⁸ cfu / ml) of the above culture solution is used. 10 ml of the culture solution of Enterococcus katsura flavus MH-3 strain (FERM p-18147) obtained in (1) was added (ΣOD80.9). Subsequently, it left still for 48 hours by pH9.0, temperature 40 degreeC, and ORP-440mV. ΣOD after the treatment was 1.7, and the decolorization rate was (1-1.7 / 80.9) × 100 = 97.9%. FIG. 3 shows a full curve of absorbance before treatment and absorbance after treatment at an absorption wavelength of 400 to 650 nm.
[0035]
Example 4
Place 100 ml of medium containing 0.5% meat extract, 1.5% peptone, 0.5% sodium chloride and 0.5% second potassium phosphate in a 300 ml Erlenmeyer flask. Amaronaticus MH-1 strain (FERMp-18145) was inoculated with one platinum ear and statically cultured at 30 ° C. for 48 hours.
300 ml of colored waste water D (including azo dye factory waste water and other dye factory waste water) is placed in a 500 ml Erlenmeyer flask, and 10 ml (2.9 × 10 ⁸ cfu / ml) of the above culture solution is used. 10 ml of the culture solution of Enterococcus casserole flavus MH-3 strain (FERM p-18147) obtained in (1) was added (ΣOD116.1). Subsequently, it left still for 48 hours at pH9.1, temperature 38 degreeC, and ORP-280mV. ΣOD after the treatment was 9.8, and the decolorization rate was (1-9.8 / 116.1) × 100 = 91.6%. FIG. 4 shows a full curve of absorbance before treatment and absorbance after treatment at an absorption wavelength of 400 to 650 nm.
[0036]
Example 5
Into a 500 ml Erlenmeyer flask, 300 ml of colored waste water E (including azo dye factory waste water and other dye factory waste water) was put, and the Enterococcus katseriflavus MH-3 strain (FERM p-) obtained in Example 1 was used. 18147), 10 ml of Morganella morgani MH-2 strain (FERMp-18146) obtained in Example 3, and Citrobacter amaronaticus MH-1 strain (FERM) obtained in Example 4. 10 ml of the culture solution of p-18145) was added (ΣOD255.6). Subsequently, it left still for 48 hours by pH8.6, temperature 34 degreeC, and ORP-350mV. The ΣOD after the treatment was 18.3, and the decolorization rate was (1-18.3 / 255.6) × 100 = 92.8%. FIG. 5 shows a full curve of absorbance before treatment and absorbance after treatment at an absorption wavelength of 400 to 650 nm.
[0037]
Comparative Example 1
Sample prepared in Example 1 [300 ml of colored waste water A (including azo dye factory waste water and other dye factory waste water) was placed in a 500 ml Erlenmeyer flask, and Enterococcus katseriflavus MH-3 strain (FERM p -18147) to which 20 ml (2.5 × 10 ⁸ cfu / ml) of culture broth was added (ΣOD149.2)] was treated with a shaking incubator for 48 hours at pH 8.5, temperature 36 ° C. and 170 rpm. . During this time, the oxidation-reduction potential (Ag / AgCl electrode standard) of the sample solution was ORP + 100 mV. The ΣOD after the treatment was 139.0, and the decolorization rate was (1-19.0 / 149.2) × 100 = 6.8%.
[0038]
【The invention's effect】
According to the present invention, it is produced in colored waste water by adding one or more bacteria selected from Citrobacter amaronaticus, Morganella morgani and Enterococcus casei flavus to colored waste water, particularly colored waste water containing azo dyes. Even if by-products, dyeing assistants, and the like are included, it is possible to provide a low-cost and practically excellent treatment method for high-concentration colored wastewater that can decompose and decolor the mixed hardly-decomposable colored compounds.
[Brief description of the drawings]
1 is a graph showing changes in absorbance and absorption wavelength before and after treatment of colored wastewater of Example 1. FIG. (Dilution ratio 50 times)
2 is a graph showing changes in absorbance and absorption wavelength before and after treatment of colored wastewater of Example 2. FIG. (Dilution 50 times)
3 is a graph showing absorbance and absorption wavelength before and after treatment of colored wastewater of Example 3. FIG. (Dilution ratio 50 times)
4 is a graph showing absorbance and absorption wavelength before and after treatment of colored wastewater of Example 4. FIG. (Dilution ratio 50 times)
5 is a graph showing absorbance and absorption wavelength before and after treatment of colored wastewater of Example 5. FIG. (Dilution ratio 50 times)

Claims (8)

One or more bacteria selected from bacteria belonging to the genus Citrobacter, Morganella and Enterococcus casseriflavus are added to colored wastewater containing a dye, pH 7.0 to 9.5, temperature 20 to 45 ° C., redox potential (Ag / AgCl electrode standard) A method for treating colored wastewater containing a dye, characterized by decolorizing under a condition of -30 to -550 mV. The method for treating colored wastewater containing a dye according to claim 1, wherein the bacterium is at least one selected from Citrobacter amaronaticus, Morganella morgani, and Enterococcus caselliflavus. Bacteria are strains of Citrobacter amalonaticus MH-1 (FERM P-18145), Morganella morgani MH-2 (FERM P-18146) and Enterococcus casei flavicos cc. -3 (FERM P-18147) 1 or more types selected from a strain, The processing method of the colored wastewater containing the dye of Claim 1. The method for treating colored wastewater containing a dye according to any one of claims 1 to 3, wherein the colored wastewater containing a dye is a colored wastewater containing at least an azo dye. The processing method according to any one of claims 1 to 4, wherein the colored wastewater containing the dye is a highly colored wastewater having a ΣOD6 or higher. Citrobacter amalonaticus MH-1 (FERM P-18145) strain. Morganella morganii MH-2 (FERM P-18146) strain. Enterococcus caseiflavas MH-3 (FERM P-18147) strain.

Images