JPS6023878B2 - Wastewater treatment method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for treating and purifying wood saccharification liquor, sulfite pulp waste liquor, etc. containing large amounts of lignin and tannin.

To date, there are no known microorganisms that can completely decompose and assimilate lignin and tannin.

Therefore, liquids containing large amounts of lignin and tannins
It cannot be directly disposed of in rivers and can only be subjected to activated sludge treatment after a combination of various chemical treatments. The cost and time required for this are enormous, and even with all this effort, it has been impossible to completely decompose lignin and tannin and render them harmless. However, pulp mill wastewater, leather factory wastewater, and other textile processing plant wastewaters are large in volume, so it is necessary to treat them safely at low cost.
Moreover, pollution of rivers and coasts by sludge must be stopped as soon as possible. As a result of various studies to solve these pressing technical issues in the industry,
It was concluded that the use of microorganisms is the best way to safely treat large volumes of wastewater at low cost.

Therefore, the present inventors believe that if a bacterium that directly utilizes lignin and tannin is discovered, wastewater containing lignin and/or tannin can be reduced by using that bacterium alone or in combination with other bacteria. He came up with the idea that the bacteria could be purified all at once, so he scoured a huge number of bacteria and studied them more deeply. They succeeded in finding a strain belonging to the genus that can directly transform lignin and/or tannin and purify wastewater containing large amounts of these at once, leading to the completion of the present invention. The bacterial strains isolated here have the previously unknown utility of assimilating lignin and tannin, and are useful for assimilating lignin and tannin, respectively.
), Trichosporon, and Pichia, and all of these four strains have been deposited at the National Institute of Fine Technology.

These strains are as follows. 1 day GnSenu
laSp. K-1323FERM P-6230 2 Tor mountain opsis sp. NY-173FERM
P-62323 Trichosporonsp, NY
-82FERM P-62314 Pichiaaca
ciae AM37WFERM P-3593 and
The mycological properties of these strains are as follows.

Hensenu! asp. K-323 wort medium (25 qo, 3 days culture): Cells are spherical to oval and elongate, membranes, subclear.

Wort agar (170, January): Gray-white smooth or dry white fungal moss.

Slide medium: extended cell connections, forming pseudohyphae.

Ascospore: A vegetative cell directly becomes an ascus, forming 1 to 4 cap-shaped spores.

Fermentation of bran: glucose, sucrose, raffinose (1/3).

Hydrogen assimilation: glycose, galactose, sucrose, maltose, ethanol.

Nitrate assimilation ability: Yes.

Vitamin requirements: None.

Tor mountain opsis Sp. NY-173 wort medium (2500, cultured for 3 days): Cells are spherical to oval, filmy, and clear.

Wort agar (17o0, 1 month): Gray fungus moss.

Slide medium: No pseudohyphae formation. Ascospores: Not formed.

Fermentation of bran: glucose, sucrose, raffinose (1/3).

Assimilation by spears: glycose, galactose, sucrose, maltose, ethanol.

Nitrate assimilation ability: None.

Vitamin requirement: Yes.

Trichosporon sp. NY-82 wort tower (cultured at 25°C for 3 days): Cells are oval and elongated, with multipolar budding.

Wort agar (170, January): Gray fungus moss.

Ascospores: Not formed. Slide medium: pseudohyphal fission formation.

Fermentation of bran: None.

〃 Assimilation: glucose, galactose, sucrose,
Maltose, eta/-le.

Nitrate: Not assimilated.

Pichia acaciae AM37W wort medium (2100, 2 days culture): Cells are spherical, oblong and elongated, clear.

Wort Agar Tower (170, January): Grayish brown, wrinkled fungal moss.

Slide culture: pseudohyphal formation.

Branches into 2-3 or many blastospores.

Ascospore formation: Formation of 2 to 4 short-edged, cap-shaped spores in an ascus produced by the joining of two vegetative cells.

Type of fermentability: glucose fermentation Nitrate assimilation ability: None.

Vitamin requirement: Yes.

In ordinary observation, these strains used in the present invention are not particularly different from the strains of the various genera that are known from their predecessors, but they are extremely unique in that they can significantly assimilate lignin and/or evening nin. It has properties that were completely unknown in the past.

In other words, bacteria that can significantly assimilate and decompose lignin and tannin have not been previously known, and known bacterial strains hardly grow even when added to wastewater containing lignin and tannin. However, each bacterial strain according to the present invention rapidly assimilates lignin and evening nin and achieves remarkable growth. Therefore, IJ Gunin and/or
Alternatively, if the culture of each strain according to the present invention is added alone or in combination to wastewater containing a large amount of tannin, it will not only utilize lignin and/or tannin and reduce the COD of wastewater. The isolated bacterial cells can be effectively used as feed and can also be used as a protein resource. The wastewater treatment according to the present invention can be widely applied to wastewater containing high lignin and/or tannin.

For example, it can be widely applied to wastewater containing lignin and tannin, such as wood saccharification liquor, sulfite pulp wastewater, crude drug processing wastewater, tannery wastewater, textile processing wastewater, and others. Moreover, the strain according to the present invention is not limited to lignin and tannin. In addition to monosaccharides such as pentoses and hexoses, it can also assimilate and decompose oligosaccharides and relatively low-molecular polysaccharides, so even if these sugars are contained in lignin and tannin wastewater, Furthermore, it is of course possible to purify these sugar-containing wastewaters all at once by mixing them with lignin and saccharide wastewaters. In the wastewater treatment according to the present invention, high lignin and/or tannin-containing wastewater itself, or pre-treated wastewater such as furnace filtration, centrifugation, chemical treatment, etc., is treated with each bacterial strain, a mixture thereof, or a mixture thereof. This is done by adding a mixed bacterial culture of bacterial strains and protein- and starch-assimilating bacteria.

The culture may be used as it is without separating the bacterial cells from a mass cultured seed, or the grown bacterial cells obtained in large quantities after wastewater treatment may be returned and used. Alternatively, pure cultured bacterial cells themselves may be used.

The amount of inoculation may be about 1 to 1 microbial cell/secretion, but the amount of inoculation may be changed as appropriate depending on the length of the culture time. The culture temperature is 2
The amount is preferably about 0 to 35 qo, particularly preferably about 25 to 30 oo, but even if the amount is less than 20 qo, it is possible to sufficiently treat wastewater by extending the culture time.

Cultivation is usually carried out aerobically, such as by shaking, aeration, or by aerating. In the processing of the present invention, if necessary,
Even better effects can be obtained by adding monopods, especially hexoses such as glucose, mannose, and fructose, as carbon sources.

Furthermore, if necessary, organic or nitrogen sources such as ammonium phosphate, potassium phosphate, sodium phosphate, lime superphosphate, ammonium chloride, ammonium nitrate, urea, ammonium sulfate, aqueous ammonia, beptone, Fish meal, bran, amino acids,
Add nutrients such as protein necessary for yeast growth. Even if the amount of inoculated bacterial cells is lower than in the case described above, if the treatment is continued, these yeasts will rapidly proliferate, so that it is possible to treat the wastewater sufficiently.

In normal cases, wastewater treatment is fully completed in 2 to 4 days, but it is important to consider the type of bacteria, type of wastewater, concentration, amount of bacteria inoculated, temperature, p.
The treatment time can also be freely manipulated by changing H, the nutrient source, etc. The treatment pH range is wide, ranging from acidic to neutral, and the pH within this range can be freely selected. The removal rate of COD by this yeast removal is generally 50 to 70%.

The wastewater treated in this manner can be sufficiently treated by other known wastewater treatment means and can therefore be freely discharged into rivers after being treated by such conventional methods.

Activated sludge methods are particularly suitable as known wastewater treatment means. That is, the wastewater treated with the bacterial cells of the present invention as described above can be used as it is, if the bacterial cells are separated, or if the wastewater is treated with C.
After appropriately mixing wastewater with reduced OD, it is sent to an activated sludge treatment tank, and COD is removed more effectively. At this time, it is possible to separate a large amount of bacterial cells in the waste liquid and use them as feed, but without separating them,
It is also convenient from a wastewater treatment perspective even if it is sent directly to the activated sludge treatment tank.Moreover, the yeast sent to the activated sludge treatment tank becomes a nutrient source for the activated sludge, increasing the activity of the sludge, which is extremely convenient for activated sludge treatment. becomes. A circulation residence time of about 10 to 3 feeding hours is sufficient.

Through this treatment, the COD50Q wind (including yeast cells) of the treated wastewater is reduced to 20 to 100 legs (after natural sedimentation of microorganisms). As described above, the present invention is capable of treating high lignin and/or tannin-containing wastewater with lignin and/or tannin belonging to the genus Hansenula, Torulopsis, Trichosporon, and Pichia.
Alternatively, the wastewater can be treated with tannin-assimilating bacteria, and if necessary, subsequently treated with activated sludge to reduce the C of the wastewater.
This method succeeded in significantly reducing OD and is of great benefit to wastewater treatment.

In addition, the grown cells of the used cells can be used as feed, etc., and are extremely useful.

Next, examples of the present invention will be shown.

Example 1 2.5% agar was added to Wickerham Beach having the following composition to adjust the pH to 4.8, and this was further supplemented with 1% tannic acid (pharmacopoeia) as a carbon source and HMu ship natural lignin (sawn). A soil for seed culture was prepared by adding 1% ethanolic extract of shoulder.

In addition, HEensenulasp. K-1323FERM
P-6230Tor opsissp. NY-73 FERM P-6232 Trichosporonsp. NY-82, FERM
P-6231 and Pichiaacaciae AM3
7W, FERMP-35 group was specially inoculated, 30:00 ○,
A seed culture was obtained by culturing for 7 hours.

Wickerham medium composition is BQ 500 (French g) CuS
04.8L0 40KI
IOO
FeC13/Mother's Day 20
200MnS04・Sun 20
400Na2Mo04・2L0
200ZnS04.7th 20
400biotin
2Ca・panto
thenate 400
foliacid
2inositol,
2000 niacin
400P one min
200
p〆idoxinHC1
400 ribonavin
200 enemies iamineHC1
400L-histidi fertilizer H
C1/ratio 0 10 (double 9) DL-methio
ni snake 20DL-tr
yptopha ship 2
0KH2P04 1.0 (g
)M peak S〇4th/7th 20th
〇． 5NaCI
O. 1 CaC12・2 days 20
0.1 (N ratio) 2S04
3.51
1.5aSPa NegIM total amount
1% and 1% each of lignin and tannin were added to Wickerham tower to each of the 1 and 4 500's Lough flasks (COD 1690 Urifu),
Each of the above seed cultures was inoculated into this (bacteria mass: 1
07/Story), cultured at 30° C. with shaking for 9 cycles, and the culture was analyzed.

The COD removal rate, shoes and bacterial cell amount were as follows.
Table 1 Example 2 In the same manner as in Example 1, however, as treated wastewater, Wickerham medium with 1% lignin added as a carbon source (COD629 neck blood, pH 60) was used, and 30 qo
After shaking culture for 9 hours, the following results were obtained.

Table 3 Example 3 The same operation as in Example 1 was performed.

However, the treated wastewater is based on Wickerham Tower, to which 0.1% tannic acid and 1% glucose are added as a carbon source (COD 4600 feet,
pH 60), the inoculation amount was 6 x 1 pi/', and 30
The culture was carried out for 9 hours at ℃, and the following results were obtained. Table 2 Example 4 4-fold dilution of sulfite pulp waste liquid (COD28710 trace)
Put 50's into each of the 500 Sakaguchi flasks,
Adjust the temperature to 5.4 and inject each with K-323 bacteria and NY-
1 each of 73 bacteria, NY-82 bacteria, and AM37W bacteria.
The remaining one was inoculated with one strain each of K-323 bacteria and AM37 bacteria, and cultured with shaking for 3 days for 72 hours to obtain the following results.

Claims (1)

[Claims] 1. A method characterized by adding lignin and/or tannin assimilating yeast belonging to the genus Hansenula, Torulopsis, Trichosporon, or Pichia to high lignin and/or tannin-containing wastewater to assimilate lignin and/or tannin. A method for treating wastewater containing lignin and/or tannin.