JP2011189330A - Device for treating kitchen waste water - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for treating kitchen waste water capable of preventing an oil part from being discharged to a sewage line before the oil part is degraded because of the falling of the oil part caused by aeration in a tank. <P>SOLUTION: The device for treating kitchen waste water comprises: a cleaning tank 30 into which the kitchen waste water flows via a kitchen waste water introduction flow path 20 from a generation source 10 of the kitchen waste water; two sheets of weir plates 32a, 32b for dividing the inside of the cleaning tank into a first region 36 into which the kitchen waste water flows from the upstream over the downstream in the cleaning tank 30, a second region 37 into which the oil part contained in the kitchen waste water is separated and degraded and a third region 38 into which the treated clean water flows; a vessel 33 which is arranged on a surface layer part of the second region 37 and is packed with micro-organism carriers 35 having micro-organisms for degrading the oil part, carried on the carriers; and an aeration device 34 arranged in the vessel 33. The upper part of the vessel 33 is constituted with a porous wall having holes through which the oil part is passable and the lower part thereof is constituted with a non-porous wall through which the oil part, micro-organisms and micro-organism carrier are not passable. Therein, the vessel 33 is arranged such that the porous wall traverses water surface of the kitchen waste water. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a kitchen wastewater treatment apparatus.

  Kitchen wastewater discharged from restaurants and other restaurants contains oil, and it is necessary to purify the kitchen wastewater before discharging it into the sewer system in order to suppress environmental degradation. For this reason, a so-called grease strap for purifying the kitchen wastewater is installed in the kitchen or outside the kitchen.

  In a general grease wrap, waste water containing oil is guided to an oil separation tank, and oil having a small specific gravity is lifted and separated from the waste water. And the oil component accumulated on the water surface of the oil separation tank is periodically collected and disposed of.

  Furthermore, various devices for decomposing the separated oil in the grease trap have been developed. For example, in Patent Document 1, a microbial filter is disposed at an upper position of a grease strap, and oil is decomposed in the microbial filter. The microbial filter is provided with a microbial carrier carrying microorganisms and an aeration pipe for aeration. By maintaining the inside of the microbial filter in an aerobic atmosphere, decomposition of oil by the microorganisms is promoted. This microbial filter is a housing having an upper surface opened and a hole formed in the bottom. Waste water is introduced from the upper opening, and the treated water is discharged from the hole in the bottom.

Japanese Patent Laid-Open No. 2002-18460

  In the kitchen wastewater treatment apparatus disclosed in Patent Document 1, wastewater is introduced from the upper opening of the microbial filter, and the treated water is discharged from the hole at the bottom. With this water flow, oil may be discharged from the microbial filter. Moreover, the residence time of the oil component in the microbial filter cannot be ensured, and the treated water may be discharged into the sewerage system with insufficient decomposition of the oil component.

  In addition, although the microorganisms are gradually separated from the microorganism carrier, the microorganisms sink in the water, and thus flow out from the holes on the bottom of the microorganism filter. For this reason, there is a problem that the amount of microorganisms in the microorganism filter is reduced and the oil cannot be efficiently decomposed.

  The present invention has been made in view of the above matters, and its purpose is to ensure the residence time of the oil separated from the kitchen wastewater, and to prevent the microorganisms and enzymes that decompose the oil from flowing out, efficiently. An object of the present invention is to provide a kitchen wastewater treatment apparatus capable of decomposing oil in kitchen wastewater.

The apparatus for treating kitchen wastewater according to the present invention comprises:
A septic tank into which kitchen wastewater flows from the source of kitchen wastewater through the kitchen wastewater introduction channel,
From the upstream to the downstream in the septic tank, a first region into which the kitchen wastewater flows, a second region to separate and decompose the oil contained in the kitchen wastewater, and a third region into which the treated purified water flows. Two dams that divide the area,
A container that is disposed on the surface layer of the second region and is filled with an oil-decomposing substance-carrying body on which microorganisms and / or enzymes that decompose oil are loaded;
Aeration means disposed in the container,
The upper part of the container is configured with a perforated wall having holes through which the oil component can pass, and the lower part includes the oil component, the oil decomposing substance carrier, the microorganisms separated from the oil decomposing substance carrier, and the enzyme. Consists of non-perforated walls that do not pass,
The container is arranged such that the perforated wall crosses the surface of the kitchen wastewater;
The oil separated from the kitchen wastewater passes through the perforated wall and flows into the container, and the microorganisms and / or the enzyme decomposes the oil.
It is characterized by that.

  Further, it is desirable that the lower part of the container is formed so that the horizontal sectional area gradually increases upward.

  Furthermore, the kitchen wastewater introduction channel may be provided with an oil decomposition solution supply device that supplies an oil decomposition solution containing microorganisms and / or enzymes capable of decomposing oil.

  In the kitchen wastewater treatment apparatus according to the present invention, a container having an upper part constituted by a perforated wall and a lower part constituted by a non-porous wall is disposed in the second region for decomposing oil, and the oil is decomposed in the container. A substance carrier and an aeration device are arranged. The oil separated from the kitchen wastewater passes through the perforated wall, flows into the container, and is decomposed in the container. Since the lower part of the container is a non-porous wall, the oil is prevented from flowing out of the container before being decomposed, and a sufficient residence time for decomposing the oil can be secured. Furthermore, the outflow of microorganisms and enzymes separated from the oil-decomposing substance carrier and the oil-decomposing substance carrier from the container is also suppressed. Thereby, kitchen wastewater can be purified efficiently.

It is a schematic block diagram of the processing apparatus of the kitchen wastewater which concerns on this invention. It is a perspective view of a container. It is a side view of the container which concerns on another form. It is a partial block diagram of the processing apparatus of the kitchen wastewater which concerns on another form. 1 is a schematic configuration diagram of an apparatus used in Example 1. FIG.

  Hereinafter, the configuration of the kitchen wastewater treatment apparatus according to the present embodiment and the purification treatment will be described with reference to the drawings. As shown in FIG. 1, the kitchen wastewater treatment apparatus 1 according to the present embodiment mainly includes a septic tank 30 from a kitchen wastewater generation source 10, dam plates 32 a to 32 c disposed in the septic tank 30, and a container 33. And an aeration apparatus 34 disposed in the container 33 and a microorganism carrier 35 filled in the container 33.

  The kitchen wastewater source 10 is a facility that discharges wastewater containing oil in the kitchen, such as a dishwasher or a sink.

  The kitchen wastewater introduction channel 20 is a U-shaped groove or the like through which kitchen wastewater discharged from the generation source 10 flows.

  The septic tank 30 is a tank that separates the inflowing kitchen wastewater into drainage and oil, and decomposes and purifies the oil. In the septic tank 30, weir plates 32 a and 32 b that divide the septic tank 30 into a first region 36, a second region 37, and a third region 38 are arranged from upstream to downstream. The first region 36 is a tank into which kitchen wastewater from which raw garbage is separated flows. Moreover, the 2nd area | region 37 is a tank which isolate | separates and decomposes | disassembles kitchen wastewater into an oil component and waste_water | drain. Moreover, the 3rd area | region 38 is a tank which stores waste_water | drain.

  The dam plates 32a and 32b do not reach the bottom surface of the septic tank 30, and the kitchen wastewater is configured to flow under the dam plates 32a and 32b. In the second region 37, a dam plate 32c is erected from the bottom surface of the septic tank 30 to the vicinity of the container 33.

  In the first region 36, that is, at a location where kitchen wastewater flows into the septic tank 30, a net basket 31 for capturing solid matter such as raw garbage flowing along with the kitchen wastewater is disposed.

  A container 33 is disposed on the surface layer portion of the second region 37. As shown in the perspective view of FIG. 2, the container 33 includes a lower non-perforated wall 33a, an upper perforated wall 33b, and a hook 33c.

  The non-porous wall 33a has a structure in which no holes are provided and fluid or solids cannot pass therethrough. The non-porous wall 33a is formed so that the horizontal cross section gradually increases upward.

  On the other hand, the upper perforated wall 33b is provided with a plurality of holes through which oil can pass. The perforated wall 33b is not particularly limited as long as oil can pass therethrough, such as a plate or a net formed with a plurality of holes such as circles and rectangles.

  The hook 33c is used when the container 33 is installed in the septic tank 30, and the container 33 is installed so as to be suspended from the upper ends of the weir plates 32a and 32b with a string or the like.

  And the container 33 is installed in a surface layer part so that the perforated wall 33b may cross the water surface of kitchen wastewater, as shown in FIG.

  An aeration device 34 is disposed at the bottom of the container 33. The aeration apparatus 34 is an apparatus that aerates the inside of the container 33 to make an aerobic atmosphere. The aeration apparatus 34 is not particularly limited as long as it can supply air (oxygen). For example, a tube having a hollow inside is provided with a hole, air is pumped into the tube and air is supplied from the hole into the container 33, or a material that releases oxygen or other gas when placed in a liquid. There may be.

  In addition, the container 33 is filled with a microorganism carrier 35 carrying microorganisms capable of decomposing oil as an oil-decomposing substance carrier.

  The third region 38 of the septic tank 30 is provided with a purified water outlet passage 40 for discharging the waste water.

  Next, the purification process will be described.

  First, the kitchen wastewater discharged from the kitchen wastewater source 10 flows into the septic tank 30 through the kitchen wastewater introduction channel 20.

  The kitchen wastewater that has flowed in passes through the bottom of the dam plate 32a and flows into the second region 37 after the solid matter such as garbage is captured by the net 31 disposed in the first region 36 of the septic tank 30. To do.

  The kitchen wastewater flowing into the second region 37 is separated into oil and drainage by specific gravity while the flow is changed upward by a weir plate 32c erected from the bottom of the septic tank 30. The oil having a specific gravity smaller than that of the drainage rises to the surface layer portion of the second region 37 and flows into the container 33 through the hole of the perforated wall 33b.

  Since the lower part of the container 33 is formed so that the horizontal cross section becomes larger upward, the rise of the oil separated by the bottom surface of the container 33 is not hindered, and the oil rises smoothly. Thereby, the oil component flows into the container 33 quickly and efficiently.

  The oil that has flowed into the container 33 is decomposed by microorganisms. By aeration, the microorganism carrier 35 and the oil component are stirred and mixed, the contact efficiency between the microorganism carrier 35 and the oil component is high, and the oil component is efficiently decomposed by the microorganisms.

  Although it takes a certain amount of time for the oil to be decomposed by the microorganisms, the lower part of the container 33 is a non-porous wall that does not have holes through which the oil and the microorganism carrier 35 flowed in. Oil does not flow out of the container 33. Therefore, the oil remains in the container 33 until it is decomposed.

  Further, for the same reason as described above, the microorganism carrier 35 and microorganisms having a specific gravity greater than that of the water separated from the microorganism carrier 35 are also prevented from flowing out below the container 33. By the microorganisms remaining in the container 33, the concentration of the microorganisms in the container 33 can be kept high, and the oil component is efficiently decomposed by a large number of microorganisms.

  Furthermore, since the lower part of the container 33 is formed so that the horizontal cross section becomes smaller downward, it is possible to prevent the microorganism carrier 35 from being accumulated in the corner of the container 33 due to agitation by aeration. Thereby, the microorganism carrier 35 is dispersed in the container 33 and spreads, the contact efficiency with the oil is increased, and the decomposition efficiency of the oil by the microorganism is promoted.

  Then, the waste water separated from the oil and flows into the third region 38 through the lower side of the barrier plate 32b is discharged to the sewer via the purified water outlet passage 40.

  The grease strap that can be installed in the kitchen is smaller than the grease strap that is installed outdoors, and the depth of the septic tank is particularly shallow. In particular, when there are kitchens on the second floor or more of the building, the grease traps installed in the kitchens have a shallow tank depth of about 30 cm, and the bulk of drained wastewater is about 20 cm. In the case of such a small and shallow tank, when air is introduced from the bottom of the septic tank and aerated, the wastewater in the septic tank is agitated, and the oil component separated and floated flows downward, and the oil component is in the third region. There is a problem of intruding into the sewage system.

  However, in the processing apparatus 1 according to the present embodiment, since the aeration is performed in the container 33 and the bottom of the container 33 has a structure in which oil does not pass, the oil flows below the septic tank by agitation by aeration. It can be suppressed. Thus, the processing apparatus 1 according to the present embodiment is particularly effective when installed in a kitchen.

  The microorganism used is preferably a photosynthetic bacterium. This is because photosynthetic bacteria are highly safe bacteria, and even if released into sewage, there is no risk of causing environmental problems.

  Moreover, since kitchen wastewater may be high temperature wastewater of 45 degreeC or more, it is preferable to use the photosynthetic bacteria which can survive also in such a high temperature range. Rhodobacter sphaeroides NAT can be mentioned as a bacterium that can survive at 45 ° C. or higher and can decompose oil.

  The microorganism carrier 35 is preferably alginate beads in which photosynthetic bacteria are immobilized with alginate. When an inorganic substance is used by supporting microorganisms, the inorganic substance is insoluble in water, and the microorganisms cannot be visually recognized. Therefore, when used for a long time, it is not known whether microorganisms that contribute to the decomposition of the oil are present. In the case of alginic acid beads, alginic acid dissolves and disappears gradually in water, so it is possible to easily determine whether or not microorganisms are present by visually checking the disappearance degree of alginic acid beads. By appropriately replenishing the alginate beads into the container 33 depending on the disappearance degree of the alginate beads, the oil can be decomposed without delay. Further, in the alginate beads, the photosynthetic bacteria are immobilized in a dispersed form, so that the surface area of the photosynthetic bacteria in contact with the oil can be increased, and the oil can be efficiently and rapidly decomposed.

  Moreover, the form shown in the side view of FIG. 3 may be sufficient as the container 33. FIG. The non-porous wall 33a at the lower part of the container 33 is formed so as to protrude in the horizontal direction, and the microorganism carrier 35 can be further prevented from flowing out of the opening of the container 33 due to aeration.

  Moreover, although the example using the microorganism carrier 35 carrying microorganisms as the oil-decomposing substance carrier has been described above, an enzyme carrier carrying an enzyme capable of decomposing oil may be used. Microorganisms release the produced enzyme, and the oil is broken down by this enzyme. For this reason, when an enzyme carrier carrying an enzyme is used, oil can be decomposed more quickly.

  As the enzyme to be used, a lipase that decomposes an ester bond constituting a lipid can be mentioned. For example, triacylglyceride lipase produced by the above Rhodobacter sphaeroides NAT may be used.

  Further, the enzyme carrier and the microorganism carrier 35 may be mixed and used, or only one of them may be used. Furthermore, you may use what carried the enzyme and microorganisms.

  Furthermore, as shown in FIG. 4, an oil decomposition solution supply device 50 may be provided in the kitchen wastewater introduction channel 20.

  The kitchen wastewater introduction flow path 20 from the kitchen wastewater source 10 such as an automatic dishwasher in the kitchen to the septic tank 30 is often a concrete groove covered with iron grating, and oil adheres to the inner wall of the groove to cause contamination. Easy to breed. By flowing the liquid degrading bacteria from the oil decomposition solution supply device 50 to the kitchen wastewater introduction channel 20, the oil adhering to the inner wall of the kitchen wastewater introduction channel 20 can be decomposed and the propagation of various bacteria can be suppressed.

  Thereby, purification of the kitchen wastewater introduction channel 20 can be performed, malodors from the kitchen wastewater introduction channel 20 can be suppressed, and the number of times of cleaning the kitchen wastewater introduction channel 20 can be reduced.

  Here, the oil decomposing solution is a liquid intervening with microorganisms and / or enzymes capable of decomposing oil, and for example, a culture solution in which microorganisms are cultured is used. As an example of the microorganism, Rhodobacter sphaeroides NAT, which is the above-mentioned photosynthetic bacterium, can be mentioned, and a culture solution obtained by culturing this Rhodobacter sphaeroides NAT is used as an oil decomposition solution. Examples of the enzyme include a lipase that decomposes an ester bond constituting a lipid. Specific lipases include triacylglyceride lipase produced by Rhodobacter sphaeroides NAT.

  The oil-decomposing solution may be constantly supplied or may be supplied intermittently at a constant rate according to the amount and frequency of the discharged kitchen wastewater.

  Further, the oil decomposition solution supply device 50 may be supplied from a tank filled with the oil decomposition solution by dropping its own weight, or may be forcibly supplied using a pump or the like.

  When microorganisms or enzymes are precipitated in a tank filled with an oil decomposition solution, for example, when a culture solution in which microorganisms are cultured is diluted with water, a stirring device may be provided in the tank. An oil decomposition solution with a constant concentration of microorganisms and enzymes can be supplied.

  Moreover, it is preferable that the oil decomposition solution supply apparatus 50 is arrange | positioned in the upstream of the kitchen wastewater introduction flow path 20, and the exit vicinity of the generation source 10 of the kitchen wastewater.

  A container having a perforated wall at the top and a non-porous wall at the bottom (hereinafter referred to as container A) and a container having a plurality of holes at the bottom (hereinafter referred to as container B) were prepared. And the apparatus shown in FIG. 5 was comprised using each container, and the microbial cell density | concentration in a container was measured with time.

  In a container A, 500 g of alginate beads on which Rhodobacter sphaeroides NAT was immobilized were charged.

  And the pump 52 was driven and the tap water with which the water tank 51 was filled was made to flow in into the septic tank 30 through the tube 53. FIG. Tap water was flowed 5 times a day (1 L at a time) for 3 days. In addition, aeration was always performed in the container A by the aeration apparatus 34. Three days later, water in the container A was collected, and the bacterial cell concentration was measured.

  Moreover, using the container B, it experimented similarly to the above and measured the microbial cell density | concentration.

The results are shown in Table 1.

  In the container B having holes at the bottom, the bacterial cell concentration was 1.0 mg / L, whereas in the container A having no holes at the bottom, the bacterial cell concentration was 6.0 mg / L. Bacteria separated from the alginate beads flow out of the bottom hole in the container B and have a low cell concentration, whereas in one container A, the bacteria are prevented from flowing out from the bottom, and the cell concentration increases. I understand that.

  The higher the cell concentration, the higher the oil decomposition ability, so it was proved that the oil decomposition ability can be improved by using a container having no holes at the bottom. And since it is suppressed that an oil content also flows out from a container similarly, it turns out that an efficient process can be performed by maintaining high microbial cell density | concentration and ensuring the residence time of an oil content.

(Purification experiment of kitchen wastewater introduction channel)
The margarine which has the vegetable oil main component similar to kitchen wastewater as a main component was applied to the U-shaped groove, and the effect when the oil decomposition solution supply device was provided in the kitchen wastewater introduction channel was verified.

  A U-shaped groove having a width of 38 mm and a length of 900 mm is prepared, and the height of both ends of the U-shaped groove is made different so that the liquid flows from one end (upstream part) to the other end (downstream part). So as to be inclined. And margarine was apply | coated to the bottom face of a U-shaped groove | channel, and the margarine layer was formed. The margarine layer was formed with a uniform width from the upstream part to the downstream part.

  And the oil decomposition solution was dripped 6 times (14:00, 16:00, 18:00, 20:00, 22:00, 24:00) every 2 hours from the upstream part. The dropping amount of the oil decomposition solution at one time was 100 mL.

  As an oil decomposition solution, a culture solution obtained by culturing Rhodobacter sphaeroides NAT was used.

  The test temperature was maintained at 30 ° C. in accordance with the room temperature in a normal kitchen.

  Then, a margarine layer having a width of 5 mm was collected at 13:00 after 1 day, 3 days, and 7 days, and the amount of oil was measured. The margarine layer was collected from three locations, the upstream portion, the midstream portion, and the downstream portion of the U-shaped groove, and the collected margarine was dissolved in a solvent to obtain a measurement test solution. This measurement test solution was measured with a Horiba oil concentration meter OCMA-305 (measurement method: H-997 extraction infrared absorption method).

  As a reference example, an experiment was performed in the same manner as described above except that tap water was used instead of the oil decomposition solution.

The results are shown in Table 2.

  Table 2 shows that when the oil decomposition solution is dropped, the amount of oil is clearly reduced as compared to when tap water is dropped. From the above results, it can be seen that by supplying the oil-decomposing solution to the kitchen wastewater introduction channel, it is possible to suppress the decomposition and propagation of bacteria and the like in the kitchen wastewater introduction channel.

DESCRIPTION OF SYMBOLS 1 Treatment apparatus 10 Generation source 20 Kitchen waste water introduction flow path 30 Septic tank 31 Net cage 32a Dam plate 32b Dam plate 32c Dam plate 33 Container 33a Non-porous wall 33b Perforated wall 33c Hook 34 Aeration apparatus 35 Microorganism support body 36 1st area | region 37 Second area 38 Third area 40 Purified water outlet flow path 50 Oil decomposition solution supply device 51 Water tank 52 Pump 53 Tube

Claims (3)

A septic tank into which kitchen wastewater flows from the source of kitchen wastewater through the kitchen wastewater introduction channel,
From the upstream to the downstream in the septic tank, a first region into which the kitchen wastewater flows, a second region to separate and decompose the oil contained in the kitchen wastewater, and a third region into which the treated purified water flows. Two dams that divide the area,
A container that is disposed on the surface layer of the second region and is filled with an oil-decomposing substance-carrying body on which microorganisms and / or enzymes that decompose oil are loaded;
Aeration means disposed in the container,
The upper part of the container is configured with a perforated wall having holes through which the oil component can pass, and the lower part includes the oil component, the oil decomposing substance carrier, the microorganisms separated from the oil decomposing substance carrier, and the enzyme. Consists of non-perforated walls that do not pass,
The container is arranged such that the perforated wall crosses the surface of the kitchen wastewater;
The oil separated from the kitchen wastewater passes through the perforated wall and flows into the container, and the microorganisms and / or the enzyme decomposes the oil.
An apparatus for treating kitchen wastewater.   The apparatus for treating kitchen wastewater according to claim 1, wherein the lower part of the container is formed so that a horizontal sectional area gradually increases upward.   The kitchen wastewater according to claim 1 or 2, further comprising an oil decomposition solution supply device that supplies an oil decomposition solution containing microorganisms and / or enzymes capable of decomposing oil to the kitchen wastewater introduction channel. Processing equipment.

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