Grease trap wastewater treatment method and wastewater treatment device

Abstract

The method for treating a waste liquid of a grease trap according to the present invention can efficiently make, into a soap liquid (including a liquid in an emulsified state), an oil and fat content floating in the waste liquid, in particular in an upper portion of the waste liquid inside the grease trap, the method involving: mixing the waste liquid inside the grease trap and a saponification agent supplied to the waste liquid with ultrasonic waves oscillating inside the grease trap to obtain a mixture liquid; and stirring and mixing the mixture liquid inside the grease trap to obtain the soap liquid. The device for treating a waste liquid of a grease trap according to the present invention is provided with an ultrasonic oscillator inside the grease trap and can mix the waste liquid inside the grease trap and a saponification agent supplied to the waste liquid with oscillation of ultrasonic waves emitted by the ultrasonic oscillator to obtain a mixture liquid.

Description

[Technical Field]

[0001] The present invention relates to a wastewater treatment method for treating wastewater in a grease trap (to convert it into soapy water) and to an apparatus for treating the wastewater. [Background technology]

[0002] For example, in kitchens of food service centers, restaurants, hotels, food processing plants, supermarkets, department stores, hospitals, and restaurants, cooking oil, food waste, leftover food, chopsticks, toothpicks, paper scraps, plastic waste, and other garbage, as well as the liquids that accompany them (hereinafter referred to as "waste liquids"). In Japan, it is prohibited to discharge such waste liquids into sewer pipes or drainage pipes, so currently, such waste liquids are stored in storage tanks (grease traps), simple grease traps, and other types of waste liquid storage tanks (hereinafter collectively referred to as "grease traps") installed inside or outside the kitchen, and the waste liquid inside the grease traps is cleaned out by a cleaning company on a regular basis, for example, once a week or once a month.

[0003] The wastewater in grease traps is treated regularly, but with the current wastewater treatment method, cleaning companies must treat the wastewater, neutralize it with a neutralizing agent, and then discharge it into the sewer or septic tank. This requires secondary work and costs, resulting in high costs. In addition, the grease trap may become full with wastewater before the next scheduled cleaning date, and the wastewater may flow into the drain pipes or sewer pipes untreated, causing environmental pollution and foul odors inside and outside the kitchen.

[0004] The inventors of this application have previously developed new wastewater treatment devices for grease traps (Patent Documents 1 to 6). These wastewater treatment devices use a pump to suck out the wastewater from the grease trap, while stirring and mixing the wastewater with saponifying salts to turn the wastewater from the grease trap into soapy water.

[0005] According to the wastewater treatment devices of Patent Documents 1 to 6, the wastewater in the grease trap can be turned into soapy liquid and returned to the grease trap or poured into drain pipes or sewer pipes, which has the advantage that these pipes are less likely to clog and the grease trap can be cleaned with the soapy liquid. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-149101 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-050918 [Patent Document 3] Japanese Patent Application Laid-Open No. 2012-106247 [Patent Document 4] Japanese Patent Application Laid-Open No. 2012-223767 [Patent Document 5] Japanese Patent Application Laid-Open No. 2013-146686 [Patent Document 6] Japanese Patent Application Laid-Open No. 2013-208616

[0007] Wastewater contains oil and fat. Oil and fat floats on water due to its specific gravity. However, the wastewater treatment devices in Patent Documents 1 to 6 described above use a hose inserted into the wastewater in the grease trap and pumped up with a pump, which inevitably pumps up a large amount of water at the bottom of the wastewater. This means that a large amount of wastewater needs to be agitated and mixed by the pump, making it difficult to efficiently turn the oil and fat in the wastewater floating at the top of the wastewater in the grease trap into a soapy solution. Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention provides a method and apparatus for treating grease trap effluent, which can efficiently convert effluent in a grease trap, particularly grease floating above the effluent, into soapy liquid. [Means for solving the problem]

[0009] The method for treating grease trap effluent of the present invention involves ultrasonically mixing the effluent in the grease trap with a saponifying agent supplied to the effluent to form a mixed liquid, and then stirring and mixing the mixed liquid in the grease trap to form a soapy liquid (including an emulsified state). In this case, it is desirable to introduce the effluent in the grease trap, mainly the oil and fat components, into a mixing section provided in the grease trap and mix it with the saponifying agent in the mixing section using ultrasonic waves. In this case, the mixed liquid flowing out of the outlet of the mixing section can be stirred and mixed at the outlet side to form a soapy liquid.

[0010] The grease trap wastewater treatment device of the present invention has an ultrasonic oscillator installed inside the grease trap, which mixes the wastewater in the grease trap and the saponifying agent supplied to the wastewater using ultrasonic waves emitted from the ultrasonic oscillator to form a mixed solution, and then agitates and mixes the mixed solution with an agitator to form a soapy solution.The ultrasonic oscillator can be installed on the partition plate, the peripheral wall, the bottom, or other locations inside the grease trap.The ultrasonic oscillator can also be installed on both or either the inner and outer surfaces of the peripheral wall of a mixing section installed inside the grease trap.An agitator can be installed on the outlet side of the mixing section, and the wastewater in the grease trap or the mixed solution flowing into the grease trap from the outlet of the mixing section can be agitated and mixed at the outlet side using the agitator to form a soapy solution. [Effects of the Invention]

[0011] The method for treating grease trap effluent of the present invention has the following effects. (1) The wastewater in the grease trap, mainly the oils and fats and the saponifying agent, is mixed with ultrasound to form a mixture, and the mixture is then stirred and mixed with an agitator, which promotes the soap liquefaction of the wastewater. (2) When the fats and oils and the saponifying agent are mixed in the mixing section, the fats and oils and the saponifying agent are easily mixed.

[0012] The grease trap wastewater treatment device of the present invention has the following effects. (1) Because an ultrasonic oscillator is installed inside the grease trap, the wastewater in the grease trap and the saponifying agent supplied to the wastewater can be mixed using the ultrasonic waves emitted from the ultrasonic oscillator, making it easier for the wastewater and the saponifying agent to mix. (2) When ultrasonic waves are generated in the mixing section installed in the grease trap, the wastewater and the saponifying agent in the mixing section are mixed efficiently. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is an explanatory diagram showing an example of a method and apparatus for treating effluent from a grease trap according to the present invention. [Figure 2] 1 is a cross-sectional view of a bellows-shaped tube according to the present invention. [Figure 3] An explanatory diagram of a general-purpose grease trap. DETAILED DESCRIPTION OF THE INVENTION

[0014] [General-purpose grease trap] Typically, waste liquid B from a kitchen or other facility is poured into grease trap A (Figure 3). This waste liquid B usually contains grease E and garbage. The garbage is collected in basket C inside grease trap A, and waste liquid B containing grease E accumulates inside grease trap A. Grease trap A is divided into sections by several partitions D1 and D2. The space below partitions D1 and D2 is open, allowing waste liquid B to pass through. The flow rate of waste liquid B flowing into grease trap A is slowed by partition D1, and the grease E accumulates on top of the water F (which usually contains sludge) due to its specific gravity. Waste liquid B inside grease trap A is gradually discharged from the outlet of trap G into the sewer or septic tank K outside grease trap A. The grease E that accumulates on top of the water F inside grease trap A is mainly a combination of glycerin and fatty acids.

[0015] (Embodiment of a method for treating grease trap drainage) The method for treating effluent from a grease trap of the present invention is a method for efficiently converting effluent from grease traps of various shapes and structures, particularly the oils and fats contained in the effluent, into a soapy solution. An embodiment of the method for treating effluent will be described below with reference to Figures 1 and 2.

[0016] The method for treating effluent from a grease trap of the present invention involves mixing effluent B in grease trap A with saponifying agent H supplied to effluent B using ultrasonic vibrations to form a mixed liquid, and then stirring and mixing the mixed liquid in grease trap A to form a soapy solution. Mixing of effluent B and saponifying agent H using ultrasonic waves can be carried out anywhere in grease trap A, but the embodiment in Figure 1 shows a case where a pipe 1 is placed in grease trap A to form a passage (mixing section) 2, and mixing is carried out in mixing section 2.

[0017] In the embodiment of FIG. 1 , waste liquid B from grease trap A flows into mixing section 2 from inlet 3 of mixing section 2. Saponifying agent H is supplied from saponifying agent container 8 into mixing section 2, and the saponifying agent H and waste liquid B that has flowed into mixing section 2 are mixed with ultrasonic waves generated by ultrasonic oscillator 5 provided in mixing section 2 to form a mixed liquid. Furthermore, the mixed liquid flowing out from outlet 6 of mixing section 2 is stirred and mixed by rotating agitator 7 provided near outlet 6 to form a soapy liquid. The soapy liquid is discharged from outlet 6 of mixing section 2 into grease trap A due to the rotation of agitator 7.

[0018] It is desirable that the waste liquid B flowing into the mixing section 2 mainly consists of oils and fats floating on the water of the waste liquid B in the grease trap A. The saponifying agent H can be supplied to the waste liquid B inside the mixing section 2 or to the waste liquid B outside the mixing section 2.

[0019] The mixture mixed by ultrasonic vibration in the mixing section 2 is stirred and mixed by the agitator 7 provided on the outlet 6 side of the mixing section 2 to form a soapy solution. The rotation of the agitator 7 makes it easier for the waste liquid B in the grease trap A to flow (be drawn) into the mixing section 2. The rotation speed of the agitator 7 is set to a speed suitable for forming a soapy solution, for example, around 1000 rpm.

[0020] The soapy liquid flowing out from outlet 6 of mixing section 2 into grease trap A hits partition plate D2 and diffuses within grease trap A. The diffused soapy liquid flows into (is drawn into) mixing section 2 from inlet 3 of mixing section 2 together with waste liquid B flowing into grease trap A from outside, such as a kitchen. The flowing waste liquid B is vibrated ultrasonically within mixing section 2 and mixed with saponifying agent H to form a mixed liquid. This mixed liquid is stirred and mixed in agitator 7 to form soapy liquid. By repeatedly liquefying the waste liquid in mixing section 2 and stirring and mixing in agitator 7, the waste liquid B in grease trap A is turned into soapy liquid.

[0021] The saponifying agent H in the present invention is a general-purpose saponifying agent that can convert the fat and oil content and water in grease trap A into fatty acids (separating from glycerin) through a chemical reaction to produce a soap solution. It also includes various processing agents such as emulsifiers, detergents, and surfactants. The amount of saponifying agent H added to wastewater B can be set as desired depending on the amount of wastewater B in grease trap A, the amount of fat and oil content, and the composition of the fat and oil (nature: plant-based, animal-based), etc. By converting the fat and oil content into fatty acids, biodegradability is much higher than that of the fat and oil content itself. The soap solution in the present invention does not necessarily have to be fully soaped, and also includes an emulsified state.

[0022] The operation timing and operation time of the agitator 7, the timing and amount of saponifying agent H to be added, etc. can be set, adjusted, and controlled as desired depending on the amount and properties of the wastewater B in the grease trap A, the type and properties of the saponifying agent H, etc. The start and stop of the operation of the agitator 7 is automatically performed at a predetermined time, for example, once a day or several times a day. The operation time for each operation can be set as desired and can be changed. The saponifying agent H is automatically added at a predetermined time, for example, once a day or several times a day. The amount added each time can be set as desired.

[0023] The mixing ratio of waste liquid B to saponifying agent H is preferably about 5:1 in terms of saponification efficiency, cost, etc., but this ratio can be changed depending on the degree of dirtiness of waste liquid B, the amount of oil and fat, and the components of the oil and fat. If the waste liquid B is significantly dirty or has a large amount of oil and fat, the amount of saponifying agent H can be made greater than the above ratio, and if the waste liquid B is not very dirty or has a small amount of oil and fat, the amount can be made less than the above ratio.

[0024] The soapy solution in grease trap A is discharged from the outlet of grease trap A into the external sewer or septic tank K.

[0025] In the present invention, as long as the wastewater B and the saponifying agent H can be mixed by the ultrasonic waves generated from the ultrasonic oscillator 5, the ultrasonic oscillator 5 does not necessarily have to be provided inside the mixing section 2. For example, it can be provided on the peripheral wall or bottom surface of the grease trap A, or on the partition plates D1 and D2. It can also be provided on the entire surface.

[0026] In the present invention, microorganisms (microbial preparations: liquid, solid, etc.), EM bacteria, enzymes, etc. can also be added to grease trap A or mixing section 2. Suitable microorganisms are those that can contribute to the saponification of wastewater B in grease trap A, such as soil microorganisms and other microorganisms. These microorganisms can be commercially available. Liquid microbial preparations are suitable for supplying into grease trap A or wastewater B in mixing section 2. Commercially available enzymes can be used. Adding these microbial preparations, EM bacteria, enzymes, etc. promotes the decomposition and saponification of the oils and fats in wastewater B in grease trap A.

[0027] (Embodiment of a grease trap drainage treatment device) An embodiment of a grease trap wastewater treatment device of the present invention will be described below with reference to Figures 1 and 2. This wastewater treatment device includes a mixing section 2 provided within grease trap A, a saponifying agent container 8 containing saponifying agent H, an ultrasonic oscillator 5 that ultrasonically vibrates and mixes wastewater B and saponifying agent H in mixing section 2, and an agitator 7 provided on the outlet 6 side of mixing section 2. The agitator 7 is driven to rotate by a motor M.

[0028] The mixing section 2 is the location within the grease trap A through which the waste liquid B passes, and can be formed, for example, by laying a pipe 1 within the grease trap A. The inner diameter of the pipe 1 depends on the size of the grease trap A, but a diameter of, for example, several centimeters to several tens of centimeters is suitable so that the waste liquid B can easily pass through without clogging. The pipe 1 is preferably made of a material that is resistant to corrosion by the waste liquid B, for example, a stainless steel pipe.

[0029] In FIG. 1, the ultrasonic oscillator 5 is fixed to the inside (inner wall surface) of the mixing section 2, but it can also be fixed to the outside (outer wall surface) of the mixing section 2, or to both the inside and outside. Also, instead of being provided at one location in the mixing section 2, it can be provided at two or more locations in the longitudinal direction of the mixing section 2 (the direction in which the waste liquid B flows). A general-purpose ultrasonic oscillator can be used as the ultrasonic oscillator 5. The oscillation frequency and oscillation power are preferably such that the waste liquid B and the saponifying agent H can be mixed efficiently. Although not shown, the ultrasonic oscillator 5 is equipped with lead wires for a power supply.

[0030] 1 has an inlet 3 that is higher than the middle section 9, and is set at the position of the grease floating above the waste liquid B in the grease trap A, making it easier for the grease to flow in through the inlet 3. The outlet 6 is also higher than the middle section 9, so that the mixed liquid flowing out from the outlet 6 flows above the waste liquid B in the grease trap A and hits the partition plate D2, spreading it within the grease trap A. Furthermore, the inner part (upward protruding part) 6a of the peripheral wall of the outlet 6 is raised higher than the outer part 6b, so that the soapy liquid agitated by the agitator 7 is discharged mainly toward the partition plate D2, and hits the partition plate D2, making it easier for it to spread within the grease trap A.

[0031] The inlet 3 and outlet 6 are raised, and the position of the middle section 9 of the mixing section 2 is lowered (towards the bottom of the grease trap A), and the ultrasonic oscillator 5 is fixed to the inner surface of the peripheral wall of this middle section 9. By making the middle section 9 lower than the inlet 3 and outlet 6, the waste liquid B and saponifying agent H tend to remain in the middle section 9, and the time they are vibrated by the ultrasonic waves is lengthened, making it easier for the waste liquid B and saponifying agent H to mix.

[0032] Although the inner surface of the pipe 1 in Figure 1 is smooth, the pipe 1 can also be a bellows-shaped pipe (a pipe with an uneven inner surface) as shown in Figure 2. In this case, microorganisms introduced into the wastewater B can easily live in the uneven parts of the bellows inner surface, making it easier for the microorganisms to grow, and the microorganisms can also promote soap formation.

[0033] The pipe 1 forming the mixing section 2 can also be arranged to meander in the depth direction of the bottom surface of the grease trap A. In this case, the mixing section 2 becomes longer by the amount of meandering, so that many ultrasonic oscillators 5 can be fixed to the mixing section 2, and the wastewater B and saponifying agent H can be vibrated and mixed by the ultrasonic waves generated from those many ultrasonic oscillators 5. The ultrasonic oscillators 5 may be fixed at a location other than that shown in the figure.

[0034] The mixing section 2 is not formed by arranging a tube 1, but can be provided with an ultrasonic oscillator 5 attached thereto, and may have any other shape or structure, such as a small chamber, as long as the ultrasonic waves emitted from the ultrasonic oscillator 5 can easily mix the waste liquid B and the saponifying agent H.

[0035] The agitator 7 rotates so as to agitate and mix the waste liquid B and the saponifying agent H. It may be a propeller type, or may be of another shape or structure, such as a submersible pump. The agitator 7 may be installed at a location other than near the outlet 6 of the mixing section 2, as long as it can agitate and mix the mixed liquid flowing out from the outlet 6.

[0036] In Fig. 1, a saponifying agent container 8 is provided so that the saponifying agent H in the saponifying agent container 8 can be supplied into the mixing section 2. The saponifying agent H may be supplied to a location other than the mixing section 2, for example, it may be supplied to the waste liquid B in the gluten trap A outside the mixing section 2.

[0037] In Fig. 1, a control panel 10 is provided. The control panel 10 can set and adjust the timing of starting and stopping the operation of the agitator 7, the rotation speed, the operation time, the timing and amount of saponifying agent H to be added, the timing and amount of microorganisms to be added, and the like, and can also check the remaining amount of saponifying agent H. In addition, the control panel 10 can notify the results of the checks and adjustments to a management department such as a management room or a manager.

[0038] The operation timing of the agitator 7 is, for example, once a day or several times a day, when it automatically starts operating at a predetermined time, and the operation time is one continuous operation time. The timing of adding the saponifying agent H is, for example, once a day or several times a day, when it automatically starts adding at a predetermined time, and the amount added is a single amount. These timings can be set at a fixed time every few days, or when a sensor detects that the amount of effluent B from the grease trap A has reached a predetermined amount. The timing and amount of microorganisms added are adjusted depending on the amount of effluent B from the grease trap A, the components of the oils and fats, etc. The control panel 10 can set, adjust, and control other conditions. [Industrial Applicability]

[0039] The above-described embodiment is a main example for solving the problem of the present invention. The present invention can be modified in design as long as the problem can be solved, and other devices can be added or changed to other devices. [Explanation of symbols]

[0040] 1 tube 2 Mixing section (passage) 3. Inlet (of the mixing section) 5. Ultrasonic oscillator 6 (Mixing section) outlet 6a Inner part (upper protrusion) 6b Outer part 7 Stirrer 8 Saponifier Container 9. Middle part (of the mixing section) 10 Control Panel A Grease trap B. Drainage C Basket D1, D2 divider E Oil content F Moisture G-Trap H Saponifying agent K Sewers and septic tanks Medium motor

Claims

1. A method for mixing a grease trap with a mixing section, the mixing section being disposed in the wastewater from the grease trap, and the mixing section being disposed in the wastewater from the grease trap. The wastewater and the saponifying agent that have flowed into the mixing section are mixed by ultrasonic vibration of the ultrasonic vibrator in the mixing section to form a mixed liquid, The mixed liquid is stirred and mixed with an agitator in the mixing section, near the outlet of the mixing section, or in a grease trap outside the outlet of the mixing section; The mixed liquid that has been stirred and mixed and is in the grease trap is allowed to flow into the mixing section through an inlet of the mixing section, The mixed liquid that has flowed in is mixed in the mixing section by ultrasonic vibrations generated from an ultrasonic vibrator in the mixing section, and the mixed liquid is stirred and mixed by the agitator, The above-mentioned flow of the wastewater into the mixing section, mixing by ultrasonic vibration in the mixing section, and stirring and mixing of the mixed liquid by the agitator are continuously carried out to turn the wastewater in the grease trap into a soapy solution. A method for treating grease trap effluent, comprising:

2. In the method for treating effluent from a grease trap according to claim 1, Add the saponifying agent to the drainage in the grease trap or the drainage in the mixing section; A method for treating grease trap effluent, comprising:

3. In the method for treating effluent from a grease trap according to claim 1 or claim 2, Microorganisms that can contribute to liquefying the wastewater into soap are added to the wastewater, and the microorganisms, wastewater, and saponifying agent are mixed in the mixing section by ultrasonic vibration to form a mixed liquid. A method for treating grease trap effluent, comprising:

4. A grease trap has a mixing section of a pipe or a small chamber, and the mixing section has an inlet through which the wastewater in the grease trap flows in and an outlet through which the wastewater in the mixing section flows out into the grease trap, There is an ultrasonic vibrator inside the mixing section, and an agitator near or outside the outlet of the mixing section, The ultrasonic vibrator generates ultrasonic vibrations in the mixing section, and the wastewater flowing into the mixing section from the inlet and the saponifying agent added to the wastewater are mixed in the mixing section to form a mixed liquid. The agitator can agitate and mix the mixed liquid in the mixing section, the mixed liquid near the outlet of the mixing section, or the mixed liquid in the grease trap outside the outlet of the mixing section, The inlet of the mixing section is provided at a height that allows the drainage or mixed liquid in the grease trap to flow into the mixing section, and the outlet is provided at a height that allows the mixed liquid in the mixing section to flow out into the grease trap, so that the mixed liquid that has flowed out from the outlet into the grease trap can flow into the mixing section from the inlet, A control unit is provided that continuously operates the ultrasonic vibrator and the agitator until the drainage liquid becomes a soapy liquid. A grease trap wastewater treatment device characterized by the above.

5. In the grease trap wastewater treatment device according to claim 4, The mixing section is a pipe or chamber sized to be placed within the grease trap; A grease trap wastewater treatment device characterized by the above.

6. In the grease trap wastewater treatment device according to claim 5, The mixing section is a bellows-shaped tube. A grease trap wastewater treatment device characterized by the above.

7. In a grease trap wastewater treatment device according to any one of claims 4 to 6, There is a saponifier container to store the saponifier. The saponifying agent container is automatically controlled by the control unit so that a predetermined amount is supplied at a predetermined time to the drainage in the mixing unit or the drainage in the grease trap. A grease trap wastewater treatment device characterized by the above.

8. In a grease trap wastewater treatment device according to any one of claims 4 to 6, The control unit can control at least one of the operation timing, operation time, rotation speed of the mixer, the timing and amount of the saponifying agent to be added, and the timing and amount of the microorganism to be added. A grease trap wastewater treatment device characterized by the above.

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