JPS6014996A - Treatment of waste water produced in food manufacture and the like - Google Patents

Abstract

PURPOSE:To perform treatment of waste water of high concentration and large fluctuation of load efficiently by removing org. substances in waste water produced in food manufacture, etc. by treating with immobilized yeast for metabolizing starch, protein, ethyl alcohol, etc. CONSTITUTION:Metabolizing yeast for at least one selected from starch, protein, fat, sugar, org. acid, amino acid, ethyl alcohol, glycerin, lignin, tannin, and pectin, is immoblized by gel entrapping method, carrier coupling method, or crosslinking polymn. method, etc. The pH of the waste water produced in food manufacture is regulated to 3-8, more pref. <=6 in order to prevent contamination by other microorganisms, and the temp. of the waste water is regulated to 10-45, more pref. 20-35 deg.C. The treatment of the waste water is performed by adding above described immobilized yeast. In addition, sodium hypochlorite, etc. is preferred to be added to the waste water in order to prevent contamination by microorganisms other than the yeast.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for treating wastewater from food production and the like using immobilized yeast.

The inventors have developed a new treatment method for food manufacturing wastewater using yeast, and efficiently treat food manufacturing wastewater with high concentrations and large load fluctuations by using yeast treatment alone or by combining yeast and activated sludge treatment. It has been shown that it can be effectively processed.

[Yoshizawa: Agriculture, J-J.

70j~7//(/g/)] The key point of the yeast treatment method is to maintain a yeast density of -108/ml or higher (usually 108/ml or higher), but depending on the conditions, the added yeast invasion or predation by other microorganisms,
The target yeast may not be able to maintain a constant yeast density due to competition with other bacteria for nutrients in the wastewater and contamination by other yeasts.

Furthermore, depending on the wastewater, it may not be sufficient to use a single yeast to completely decompose all the organic matter in the wastewater, and it may be more effective to use a mixture of several types of yeast. In such cases, several types of yeast do not always exhibit a stable bacterial flora; rather, a single yeast strain with strong viability often suppresses other yeasts.

Therefore, as a result of intensive study on a method for keeping the desired yeast at a stable density, it was discovered that by using wastewater treatment yeast as an immobilized yeast, all the problems of conventional yeast treatment methods could be solved, and the present invention was developed. Completed 1~.

Hereinafter, the non-invention will be explained in detail.

The yeast used in the present invention may be any yeast for wastewater treatment used by the inventors. Organic matter in food manufacturing wastewater mainly consists of starch, protein, fat, their intermediate decomposition products, and their constituent units, such as sugars and organic acids.In addition, alcohol manufacturing wastewater contains alcohols such as ethyl alcohol and glycerol. Wastewater from the production of wine and brandy contains lignin and tannin, and wastewater from the production of fruit juice and the like contains pectin as non-degradable substances.

1- Therefore, depending on the composition of the target wastewater, for example, yeast having the ability to assimilate various organic substances shown in Table 1 may be immobilized.1- Depending on the wastewater, a mixture of two or more types of yeast may be immobilized. Or, by mixing two or more types of yeast and then treating with the immobilized yeast, single-child water can be effectively treated.

If immobilized yeast is used, the mixing ratio of two or more types of yeast can be freely selected depending on the type of wastewater, and a stable ratio can always be maintained.

The target wastewater is mainly food manufacturing wastewater, but
Any wastewater containing organic substances shown in Table 1 can be sufficiently treated. For example, in industries that use fats and oils as raw materials, wastewater contains large amounts of organic acids and glycerol, and by using immobilized yeast that assimilates and decomposes these organic substances, organic substances in wastewater can be significantly reduced. Can be done.

Yeast may be immobilized using any known immobilization method, such as gel entrapment method, carrier binding method, or crosslinking polymerization method.

The conditions for wastewater produced by immobilized yeast are that the pH of the wastewater is between 3 and 3.
Within a wide range, preferably K pH, 4 or less to prevent contamination by other microorganisms, and the treatment temperature varies depending on the yeast used for immobilization, but is 10-4T! ℃ range, preferably 20 to 33'C.

To prevent contamination by microorganisms other than yeast, p.
Vitt.

It is more effective to add 65 ppm every day or every other day.

The material of the treatment tank is not particularly limited, but acid-resistant materials are desirable. The treatment tank can be aerated and agitated using an air pump or the like, and in some cases, agitated by an agitator to further increase the aeration effect. Many food factories have empty tanks that are not in use.
Since these empty tanks can be used as immobilized yeast tanks simply by attaching an air pump, according to the present invention, wastewater treatment can be carried out at extremely low cost.

In the case of wastewater containing low concentrations of organic matter, it is possible to bring the water quality below the wastewater standard with only immobilized yeast treatment, but in the case of wastewater containing organic matter with high (seismic intensity), immobilized yeast treatment and activated sludge method, etc. By using biological treatment or physicochemical treatment such as activated carbon adsorption in combination, the space for equipment storage and construction costs can be significantly reduced compared to the case of each treatment alone.The following examples further illustrate the present invention. It should be understood that the present invention is not limited to these Example 11rc.

Example/Yeasts listed in Table 2 were each inoculated into 700 ml of YM medium with a platinum loop, and cultured with shaking at 30° C. for λ days in a Sakaro flask. The obtained bacterial cells were sterilized with 100ml of sterilized water.
It was washed twice and suspended in sterilized water to a ratio of 10 x/0/rn14.

On the other hand, 1ml of distilled water was added to sodium alginate/7 and cellulose powder/1ml, heated and dissolved, and then cooled to room temperature, to which was added 13ml of the above yeast suspension,
After stirring well, the mixture was added dropwise into a j% calcium chloride solution to produce immobilized yeast beans with a diameter of about 3 mm.

Yeast density in immobilization gels from JX/07/V! It becomes X/0'/f/.

Next, each of the wastewaters listed in Table 2 was put into a 700 ml Sakaguchi flask, each immobilized yeast 207 was added thereto, and the flasks were shaken at 30°C. As a result, as shown in Table 2, the total organic carbon (TOC) removal rate after the immobilized yeast treatment was ~22%.

In addition, the COD after immobilized yeast treatment of washed rice Its water supernatant
30-j, 2 ppm, and the water quality is such that it is possible to discharge 1-1 as long as the pH is finely adjusted.

Example 1 Rice washing wastewater/Pihia Nakazawa LKB-33 in θ0m1i
Evening suspension, Thesocalomicop/S. fibrigera IFO
A suspension of 0103 and a mixed suspension of both were immobilized in the same manner as in Example 201, respectively, and then shaken in a Sakalo flask at 30° C. for 21 hours. the result,
As shown in Table 3, it was possible to treat wastewater more effectively by immobilizing both yeasts by mixing them than by immobilizing each yeast individually.

Example 3 Vihear Nakazawa LI immobilized in the same manner as Example/
KB-333, Hansenula anomala Y-/ and Satucharomycopsis fibrigera IFOO/θ3, respectively, alone and as a mixture of three types of immobilized yeast, 20? Accordingly, 100Ql of mixed wastewater of rice washing wastewater and alcohol-containing refined wastewater (alcohol content: approx./%) was shaken at 30°C for 3 days. As a result, as shown in the table, it was revealed that the most effective wastewater treatment was achieved with the mixture of the three glazes of immobilized yeast.
Immobilization was carried out in the same manner as in Example (~Pichia Nakazawa LKB-33 4-, 200?).
The mixture was transferred to an activated sludge tank and aerated and agitated for 3 days. As a result, the TOC of the effluent water was 30 ppm.

implementation? 11 Washed rice wastewater (T (JC/g00ppm)/L with 7% Nzenula anomala Y-/ immobilized product, l!00 g for 30
℃λ day treatment 1-1 Powdered activated carbon, 2f'f to the supernatant liquid
：The result of measuring TOC of the filtrate after 1 hour of stirring and leaving it for 1 hour.
100ml of supernatant liquid left in the sun (TOC3gOpwm)
was added to 20 g of immobilized Hansenula anomala Y-7 and shaken in a Sakalo flask at a temperature of 20-2 degrees Celsius per day, followed by an operation in which the treated water was replaced with fresh rice washing waste water supernatant. As a result of continuous treatment for two months, the TOC of the treated water was
There was almost no variation between o and 70 pP.

Patent applicant Shigeru Mizuno, Commissioner of the National Tax Agency 11 Agent Shizuyu Tatonuma 1-1 Sakuragaoka, Setagaya-ku, Tokyo 1Kiraikyo University of Agriculture 0 shots clear by Kenkichi Kodama 25 Iizuka, Iidayo-cho, Minamiakita-gun, Akita Prefecture Address Kodama partnership company

Claims (1)

[Claims] (1) A method for treating wastewater from food manufacturing, etc., characterized in that wastewater from food manufacturing, etc. is treated with immobilized yeast to remove organic matter contained in the wastewater (2) Immobilized yeast. is a mixture of seven or more types of immobilized yeast.(3) The method for treating wastewater from food manufacturing, etc., according to claim 1, wherein the immobilized yeast is a mixture of seven or more types of yeast. A method for treating wastewater from food manufacturing, etc., as set forth in claim 1, wherein the yeast is immobilized. The method for treating wastewater from food manufacturing, etc., according to any one of claims 1 to 3, wherein the yeast has the ability to assimilate and decompose seven or more types selected from tannins, tannins, and pectins.