JPH06182386A - Method for treating kitchen waste water - Google Patents

Abstract

PURPOSE:To treat efficiently kitchen waste water containing various kinds of oil to prevent pollution of river and sea water by assimilating and decomposing components contained in the waste water by contacting the kitchen waste water with one or more kinds of yeast having coagulation and/or adhesion properties. CONSTITUTION:In the method for treating kitchen waste water, the waste water is brought into contact with one or more kinds of yeast having coagulation and/or adhesion properties to assimilate and decompose the components contained in the waste water. The yeast useful for this purpose is selected from among yeast of Hansenula genus, e.g. Hansenula anomala and yeast of Kluyveromyces genus, e.g. Kluyveromyces markisianus, K. clatis, yeast of Candida genus, and yeast of Trichosporon genus. Since these kinds of yeast have a good property to assimilate the components of the kitchen waste water, the waste water can be treated efficiently by contacting the water with them according to a usual method of waste water treatment.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for efficiently treating kitchen wastewater, which is a complicated and difficult-to-treat wastewater containing various components in high concentrations, by a small-scale apparatus.

In recent years, regulations on drainage have become stricter from the viewpoint of pollution prevention, and restaurants and hotels with large kitchens have been designated as specific facilities by the Ordinance for Enforcement of the Water Pollution Control Act, and kitchen drainage discharged from them has also been designated. Although it cannot be discharged to the public sewer without treatment, the present invention is a very excellent method for treating wastewater performed in such a specific facility. Of course, the wastewater treatment method according to the present invention is extremely useful for treating household wastewater and factory wastewater from a factory, and the present invention also plays an important role in these fields.

[0003]

2. Description of the Related Art Biological methods, chemical methods, and physical or mechanical methods have been conventionally known as methods for treating organic wastewater.
A new treatment system using yeast has been developed, and it has been clarified that high concentration and severe fluctuation of load of food manufacturing wastewater can be efficiently treated by yeast treatment alone or by combining yeast and activated sludge treatment. Yoshizawa: Farming, 55,
705-711 (1981)

However, the above-mentioned treatment system still cannot sufficiently meet the needs of the industry, and particularly in the case of kitchen wastewater, an ideal industrial method capable of efficiently treating this has not yet been developed. is there. In recent years, particularly from the viewpoint of pollution prevention, regulations on wastewater have been strengthened, and as a result, it has been strongly requested by the government to sufficiently treat kitchen wastewater from restaurants and cafeterias.

[0005]

In spite of such demands, a system capable of treating kitchen wastewater efficiently and quickly with a compact device has not yet been developed. Kitchen wastewater is particularly difficult to treat because it contains not only a wide variety of components but also a high concentration and is discharged batchwise in large quantities.

[0006]

The present invention has been made for the purpose of solving the above problems and developing a new system for efficiently treating kitchen wastewater.

[0007] As a result of various studies to achieve the above object, the kitchen wastewater contains a large amount of sugars, proteins, fats and oils, and other components in high concentration. We have recognized the need to select microorganisms that are not only degradable, but can also withstand various physical and chemical conditions. As a result of further study, a small and compact processing device must be provided in order to be able to process in a hotel or restaurant. For that purpose, a carrier or a contact material is provided in the processing tank, which is excellent. It was decided for the first time that it was advisable to attach microorganisms having a resolution, and it was decided to select microorganisms that can satisfy these conditions.

Therefore, among various microorganisms, particular attention is paid to yeast, and various yeasts are subjected to an appropriate screening, and as a result, various kitchen drainage components can be efficiently decomposed and various physical And, it was the first time to separate yeast which can withstand chemical conditions and has excellent adhesion to contact materials and excellent cohesiveness in order to increase the cell density.

Yeasts suitable for the purposes of the present invention include Hansenula yeasts such as Hansenula anomala, and Kluyveromyces yeasts such as Kluyveromyces marxianus, K. Lactis, Candida yeast, and Trichosporon yeast.

[0010] These yeasts are
150 other microorganisms obtained from drains of various food factories
As a result of screening the strains, dozens of strains were found to be capable of assimilating kitchen drainage components and were obtained by identifying them. Representative strains include the following: Hansenula Anomala (Hansenula an)
omala) J-224 (FERM P-7671),
Same as J-45-0, Hansenula Fabiani (H. fab
ianii) J-640; Kluyveromyces marxia (Kluyveromyces marxia)
nus) J-673 (FERM P-10385); Candida species (Candida sp.)
(FERM P-3965); Trichosporon sp. AN-1
61.

Since these yeasts are excellent in assimilating components of kitchen wastewater, they can be efficiently treated by bringing them into contact with the wastewater of the kitchen and treating them according to a conventional method of wastewater treatment. In this case, yeast may be used alone or in combination of two or more. And for yeast,
In addition to directly using yeast itself, it is also possible to use it by preliminarily acclimatizing it in the wastewater of the kitchen and use it, or it is also possible to use the culture or a treated product obtained by concentrating or pasting or diluting it. Is.

Since these yeasts are excellent in assimilation of sugars, proteins, and other components of the kitchen drainage including fats and oils, they can be sufficiently treated by bringing them into contact with the kitchen drainage according to a conventional method of drainage treatment. Although the object can be achieved, in order to further improve efficiency or industrialization, it is necessary to increase the concentration of yeast cells in the treatment tank to accelerate the decomposition rate in the tank to improve the treatment efficiency.

Further, even for wastewater having a large amount of water and a relatively low pollutant concentration, it is possible to treat it in a short time by increasing the yeast cell concentration in the tank to improve the treatment efficiency, and to install a treatment facility. The area can be reduced.

The point of wastewater treatment by yeast is 10 ⁸ / m
It is preferable to maintain a yeast density of 1 or more, but depending on the conditions, causes such as lysis or predation by microorganisms other than added yeast, competition of nutrient intake in wastewater with other bacteria, and contamination with other yeast The target yeast is 10 ⁸ /
The yeast density of more than ml may not be maintained.

On the other hand, the yeast used in the present invention is excellent in assimilation of kitchen wastewater components, and is itself excellent in cohesiveness and adhesiveness. Therefore, yeast alone can maintain the above high yeast density. It is possible to treat the kitchen wastewater efficiently, but in the present invention, as a system for further increasing the bacterial cell concentration to further improve the efficiency of wastewater treatment, consideration is also given from the viewpoint of the treatment device, and In order to reduce the outflow as much as possible and increase the yeast cell concentration in the tank, a carrier or contact material is provided in the tank and yeast is attached to this to prevent the yeast in the tank from being washed away and to increase the bacterial cell concentration. It has succeeded in treating organic wastewater in an efficient yeast tank.

Further, one of the outstanding features of the present invention is that the yeast used in the present invention is excellent in adhesion and / or cohesiveness to a carrier or a contact material, and at that time, the yeast drainage from the kitchen. This is the point that the activity of utilizing components is not impaired. Furthermore, a further noteworthy feature is that these yeasts are capable of widely and freely immobilizing contact materials having various materials, various shapes, and various sizes. The fact that yeast, which has a high kitchen wastewater treatment capacity, has been firmly immobilized on various carriers has never been reported before, and the present invention is the first.

Another aspect of the present invention is an organic combination of these new findings, in which a fixed or partially fixed contact material or a non-fixed contact material is installed in the treatment tank, Yeast having cohesive and / or adhesive properties is attached to this to perform kitchen wastewater treatment.

Examples of the contact material include granular contact material, rod-shaped contact material, tubular contact material, plate-shaped contact material, grid-shaped contact material, mat-shaped or mesh-shaped contact material, flexible contact material, small tubular body. ,
Molded resinous fillers and / or large shipping rings, dressing rings, or Kura type fillers can be used widely and freely, and can be used alone or in combination of two or more kinds.

Specific examples of the contact material are as follows, but in the present invention, any type of contact material can be used as long as it falls within the above range.

Granular contact material: Glass and plastic beads, granular carriers such as activated carbon having various sizes, and gravel and the like are also included.

Rod-shaped contact material: A wide range of rods or rods having various cross-sections such as square rods having various lengths, round rods, etc.

Cylindrical contact material: A contact material in which a rod-shaped contact material is hollow to form a tubular shape.

Plate-shaped contact material: flat plate, corrugated plate, curled or bent flat plate, curled or bent liquid plate,
Various deformed plates are included in a wide range.

Lattice contact material: Various deformable contact materials based on a lattice, such as a long and narrow carrier formed in a lattice shape and a shape in which it is shaped like a lattice.

Mat-like or net-like contact material: A contact material made of mat-like, coarse, cloth-like or net-like fibers, synthetic resin and other materials, and a plate-like body of these materials or a space between them. A wide range of materials, such as those in which a large number are joined together, the plate-like body formed into a cylinder or a square tube, or a three-dimensional net body.

Flexible contact material: fibrous, cloth-like, sheet-like,
A contact material made of a flexible material having a string shape, a band shape, a ribbon shape, a thin piece shape, or the like is all included.

Small tubular body: All relatively small tubular bodies are included, but in addition to the precise tubular body, for example, it is deformed like a small container for lactic acid bacterium beverage with the bottom removed. Also included are tubular bodies.

Further, various packings used in the chemical industry such as packings for distillation columns can be used, and the Rasshipi ring, which is one of the above-mentioned small cylindrical bodies, and the lessing with partitions. Rings, clays, McMahon fillings reticulated from them, Stedman fillings and the like can be advantageously used.

Molded resinous packing: Plastic packing in chemical industrial equipment such as a drying tower, a washing tower, and a cooling tower is widely used. For example, a wheel-shaped circular body in which a large number of rings are radially arranged, or a ring having a circular, circular, rectangular or elliptical cross section in the circular body,
Similarly, one with a space or perforation in the same central part, one with an outer ring circle similarly on the outer periphery, or a circular body with a large number of spokes arranged radially, and a wheel shape with an outer ring circle on its outer periphery. It is possible to use those that have been made.

For this purpose, commercially available products can be used as appropriate, and for example, a flower-shaped filling material, TELLERETT.
E) (registered trademark of Nittetsu Kakoki Co., Ltd.) is exemplified. Further, in the present packing, in addition to the structure radially arranged on the horizontal plane of the ring as described above, a structure in which rings are arranged three-dimensionally radially can be used.

In the present invention, these contact materials may be molded into a certain shape, or may be variously deformed or atypical. Further, with respect to the surface, it is also possible to make the surface rough, provide irregularities or undulations, make it porous, make relatively large holes, or make a net-like structure.

Further, in the present invention, the contact material can be used not only as it is, but also the same kind or different kinds can be used together. Furthermore, the individual contact materials can be laminated, aggregated, or bundled to be used together. As an example thereof, for example, a plurality of plate-like contact materials may be laminated at intervals, and flat plate or corrugated plate-like contact materials may be laminated in the same kind, or both may be mixed and laminated. Alternatively, the corrugated plate-like contact material may be alternately focused in the opposite direction to form a kind of honeycomb structure, or the corrugated plate and the flat plate-like contact material may be alternately focused directly to form a modified honeycomb structure.
Furthermore, a contact material having a honeycomb structure can be obtained by converging various kinds of square tubes, and a porous cylindrical structure can be obtained by converging the cylinders. The porous body having such a structure is also very effective as the contact material in the present invention.

When these contact materials are installed in the treatment tank, the contact materials or a combination of several contact materials may be placed in the tank non-fixed, that is, in a free state. A plurality of or a large number of contact materials may be housed in the support, and the support may be arranged in the tank. At that time, a net-shaped or perforated container is used as a support, and one or more shelves are provided on the container for the purpose of improving the efficiency of the treatment, and a contact material is arranged leaving a space therein. as well as/
Alternatively, a shelf without a contact material may be provided so that the drainage and the yeast are brought into sufficient contact with each other. In order to prevent the individual contact materials from running away, it is advisable to provide a net or baffle plate, etc. for preventing runoff on the upper surface of the processing tank.
Alternatively, a relatively large support accommodating the contact material may be arranged in a processing tank having a support base in the lower part and a contact material floating prevention base in the upper part. At that time, it is preferable to arrange a drainage moving space, a straightening vane, an air diffusing pipe, and the like in the tank so that the yeast and the wastewater are in sufficient contact with each other.

The present invention also includes fixing the contact material to the processing tank. For fixing, the contact material may be directly fixed to the bottom surface and / or the side surface of the processing tank, or the contact material may be fixed to the support pillars or partition walls provided in the tank. In the latter case, for example, a large number of molded resinous fillers, for example, Terralet (registered trademark) may be fixed at regular intervals to one or more pillars arranged in the tank. In addition, for example, the contact material that is focused, collected, or laminated is
Normally, this is fixed upright in the tank, but this is fixed by providing a space at the bottom and a draft tube or space at the center or at an appropriate place, and further by providing an air diffuser to improve efficiency. If possible, effective wastewater treatment is possible.

Furthermore, a partially fixed contact material can also be used in the present invention. As the partially fixed contact material, the flexible contact material described above can be used, and fibrous, rod-shaped, tubular, string-shaped, strip-shaped, ribbon-shaped and / or flaky contact materials can be widely used. it can.

In actual use, for example, one end of the string-shaped contact material is fixed to the bottom surface, wall surface and / or top surface of the processing tank so that the string-shaped body does not flow out of the tank and is still in the tank. It swings or floats the wastewater without being fixed inside. Therefore, both ends of the long string-shaped contact material may be fixed to both wall surfaces of the processing tank while holding the slack, or if necessary, the intermediate portion may be fixed to the bottom surface or wall surface of the processing tank at an appropriate position. Good.

The partially fixed contact material according to the present invention includes:
Any flexible material can be used, and rod-shaped bodies, tubular bodies, and other contact materials can be widely used.

Furthermore, even if the material itself does not retain flexibility, it can be used as a partially fixed contact material in the present invention by imparting flexibility. For example, if a contact material made of a rigid body is fixed to a processing tank via a flexible material, flexibility can be imparted, and various types of immobilized carriers can be freely used in the present invention.

As a specific example thereof, glass fiber, a synthetic resin string or a hollow pipe may be fixed to a carrier having a high ability to immobilize microorganisms, and this may be fixed to a tank, or it may be made of vinyl chloride or other synthetic resin. Strings, rods, plates, cylinders, etc.
Fibers or the like may be attached and fixed to the tank. Also,
A carrier such as beads may be put on a string and a part or both ends of this string may be fixed to the tank. Instead of fixing the beads to the string one by one in this way, several beads are mesh bags. Alternatively, one bag or more may be hung on a string.

As described above, according to any of the above methods according to the present invention, not only flexible materials but also other materials can be freely used as a partially fixed contact material.

To treat wastewater according to the present invention,
The kitchen wastewater is supplied into the treatment tank with or without the contact material, and the yeast wastewater-assimilating yeast (Hansenula spp., Kluyveromyces spp., Candida spp., And / or Trochosporon spp. ) Is used, the conventional method may be used. That is, the kitchen wastewater is stored in a raw water tank, and the wastewater is directly or diluted and then sent to a treatment tank (yeast tank) to maintain the pH and temperature suitable for the growth of yeast in the treatment tank as necessary. For example, continuous treatment or batch treatment may be performed by aeration stirring with an air pump or mechanical stirring with a stirrer. In the case of using the contact material, the yeast densely adheres to the contact material and agglomerates to increase the cell concentration during the contact,
Effective and rapid processing is performed. At that time, since the contact material does not flow out of the tank, the yeast cells do not run off, and a high cell concentration is maintained. On the other hand, for example, the non-immobilized or partially fixed contact material rocks in the wastewater. Therefore, not only does it not hinder the stirring, but the air permeability is improved, so that the bacterial cell concentration is further increased, and the wastewater treatment is further promoted. Yeast used in the present invention is not only excellent in assimilation of kitchen wastewater components, but also often has excellent cohesiveness and / or adhesiveness, even when a contact material is not used, The yeast itself aggregates with each other or adheres to the vessel wall surface of the treatment tank to increase the density of the yeast, and the kitchen wastewater can be treated very efficiently even in a small treatment tank.

The treated water thus obtained can be discharged as it is to a public sewer, but if necessary, it can be subjected to physical or chemical treatment such as sedimentation or coagulation treatment or activated according to a conventional method. It may be subjected to biological treatment such as sludge treatment and then discharged.

Therefore, according to the present invention, kitchen wastewater, which has been increasing its discharge amount in recent years and which has been difficult to treat, is treated extremely efficiently and made harmless to public sewers and rivers. Since it can be discharged, it is also an excellent pollution control technology and plays a major role in preventing pollution of rivers and oceans.

The kitchen drainage includes all the large amounts of drainage from large kitchens such as hotels, school lunches, factory lunches, hospital lunches, restaurant streets, and the drainage from Japanese and Western Chinese and various other kitchens. . Further, since the method of the present invention can be carried out extremely efficiently, the apparatus can be miniaturized and made compact. Therefore, in addition to the various types of kitchen drainage described above or a large amount of drainage, various small-scale restaurants and restaurants are also available. , Kitchen wastewater discharged from coffee shops, restaurants, homes, etc. can be advantageously treated. It can be treated at home or at home, and the wastewater treatment cost of the local government can be reduced accordingly. It will be.

Examples of the present invention will be described below.

Example 1 A Chinese cooking kitchen drainage having the characteristics shown in Table 1 below was treated in a treatment tank consisting of 11 jar fermenters in which a string-shaped contact material (trade name: ring lace) 30 cm was installed.

[0047]

[Table 1]

As yeast, Hansenula an
Omala J-224 (FERMP-7671), under the treatment conditions shown in Table 2 below, the kitchen wastewater is continuously sent to the treatment tank by 1 liter per day to perform wastewater treatment,
The results shown in Table 3 below were obtained.

[0049]

[Table 2]

[0050]

[Table 3]

As is clear from the above results, an excellent removal rate was obtained by the present invention.

Example 2 In the same manner as in Example 1, the Chinese food kitchen wastewater was treated under the treatment conditions shown in Table 4 below.
Excellent results were obtained with a COD removal rate of 70%, a BOD removal rate of 80%, and an n-hexane extract removal rate of 95%.

[0053]

[Table 4]

Example 3 In the same manner as in Example 2, the Chinese food kitchen wastewater was treated and the results shown in Table 5 below were obtained. As is clear from the results, excellent results were obtained with a COD removal rate of 76%, a BOD removal rate of 97%, and an n-hexane extract removal rate of 99% or more.

[0055]

[Table 5]

[0056]

INDUSTRIAL APPLICABILITY According to the present invention, a yeast which is particularly excellent in kitchen wastewater treatment ability and which can be firmly fixed to various contact materials is newly discovered. In addition, or by using a treatment tank in which various contact materials such as a fixed or partially fixed contact material or a non-fixed contact material with such yeast are installed, it is possible to maintain a high concentration of yeast cells. It is the first successful one.

Therefore, by using such a wastewater treatment tank, various oil and fat-containing wastewater can be treated very efficiently. And since the wastewater treatment according to the present invention can be carried out on a large scale or a small scale, in addition to kitchen wastewater treatment facilities such as factories, schools, hotels, and large restaurants, small-scale restaurants, restaurants, and Furthermore, kitchen wastewater can be treated very easily and efficiently in each household, various legal regulations can be cleared, and river and ocean pollution can be prevented.

Continuation of the front page (72) Inventor Osamu Suzuki 3-5-5 Hatchobori, Chuo-ku, Tokyo DTee Co., Ltd. (72) Innovator Yoshinobu Nitta 3-3-5 Hatchobori, Chuo-ku, Tokyo T-CO., LTD. In DEE

Claims (3)

[Claims] 1. A method for treating kitchen wastewater, which comprises contacting one or more yeasts having cohesive and / or adhesive properties with the wastewater from the kitchen to assimilate and decompose components contained in the wastewater from the kitchen. 2. The kitchen wastewater is diluted if necessary, and then introduced into a treatment tank containing a contact material to which cohesive and / or adherent yeast is adhered, and aeration and pH adjustment are performed in the treatment tank. While treating the treated water to obtain treated water and / or subjecting the treated water to physical or chemical treatment such as sedimentation and coagulation treatment to obtain further treated water. Processing method. 3. The yeast according to claim 1 or 2, wherein the yeast belongs to the genera Hansenula, Kluyveromyces, Candida and / or Trichosporon.
The method described in.