JPH10202007A - Oil separation of kitchen waste water and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To separate and remove emulsified fat and oil components by floatation, to sterilize putrefactive bacteria and to prevent the generation of malodors by electrolyzing waste water by a first electrolysis section consisting of a bivalent or tervalent metal as a dissolution electrode and a second electrolysis section consisting of copper as a dissolution electrode. SOLUTION: An electrolytic treatment chamber 3 is provided with the first electrolysis section 12 consisting of aluminum or iron which is the bivalent or tervalent metal as the dissolution electrode and the second electrolysis section 16 consisting of copper as the dissolution electrode in combination. The kitchen waste water contg. the emulsified fat and oil components flows to the first electrolysis section 12 of the electrolytic treatment chamber 3 where the waste water is subjected to an electrolysis to electrically neutralize and destroy the emulsified oil drops electrified negative by the generation of the positive-electrified bivalent or tervalent metal ions from the anode side. The emulsified fat and oil components return to the initial fat and oil components and are subjected to the floatation and separation by the sensible difference in sp. gr., by which the fat and oil components are removed. Further, the kitchen waste water flows to the section electrolysis section 16 as well where the waste water is similarly subjected to the electrolysis. The copper ions from the anode side sterilize the anaerobic sulfate reduction bacteria which are one family of the putrefactive bacteria. The generation of the malodors by putrefaction is thus prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for separating and removing fats and oils from kitchen wastewater containing emulsified fats and oils from restaurants and cafeterias by electrolysis, as well as for preventing decay and sterilizing.
The present invention relates to a deodorizing method and apparatus.

[0002]

2. Description of the Related Art Conventionally, kitchen wastewater containing oil from restaurants and cafeterias has been used to remove oil using floatation due to the difference in specific gravity between oil and water using a grease strap or the like, and the treated water flows out. I have. In recent years, in restaurants and cafeterias, etc., mechanical washing of dishes and the like is frequently used to save labor, and dishes and the like are washed by using a surfactant and imparting a mechanical stirring action. A high degree of emulsification is formed by micelles, which are aggregates of the above surfactant molecules incorporating dirt such as the above. When the surface active agent is washed with a surfactant, the surface of the surface active agent is negatively charged in the waste water, and the emulsification is stabilized by the repulsive force of the same ions. On the other hand, by adding an aqueous solution of a cationic surfactant to the negatively charged dirt micelles, the micelles are electrically neutralized and the micelles are destroyed. Can be removed.

[0003]

By the way, in the conventional method of treating kitchen wastewater, the diameter of emulsified droplets is remarkably miniaturized. Therefore, it is expected that the oil content can be removed by utilizing the floating separation based on the difference in specific gravity. Not likely. In addition, kitchen wastewater contains a large amount of organic matter and is easily rotted in the summer due to bacteria, so that it emits a bad smell. However, no consideration has been given to deodorization. Further, since the cationic surfactant is highly toxic and expensive, it may not be applicable to the destruction of the micelles in kitchen wastewater. The present invention is to separate and remove the emulsified fats and oils by floating separation by electrolysis using a dissolving electrode of a divalent or trivalent metal such as aluminum or iron and copper, and to prevent the sterilization of putrefactive bacteria and the generation of offensive odor. It is an object of the present invention to provide a method and an apparatus for separating oil and water from kitchen wastewater which can be used.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a divalent or trivalent diluent for kitchen wastewater containing oils and fats and oils and fats emulsified by a surfactant. The wastewater is electrolyzed by a first electrolytic unit using a metal as a melting electrode and a second electrolytic unit using copper as a melting electrode. The present invention relates to an oil / water separator for kitchen wastewater containing a fat and oil and a fat and oil emulsified by a surfactant, wherein an inflow chamber into which the wastewater flows, and a divalent or trivalent metal adjacent to the inflow chamber An electrolytic treatment chamber for dissolving the wastewater from the inflow chamber with a first electrolytic part having a melting electrode as the first electrolytic part and a second electrolytic part having copper as the dissolving electrode; and an electrolytic treatment chamber adjacent to the electrolytic treatment chamber. And an outflow chamber through which the treated water flows out. The present invention is characterized in that the first electrolytic unit uses aluminum or iron as a melting electrode. The present invention is characterized in that each electrode of the first electrolysis unit and the second electrolysis unit is subjected to polarity conversion to electrolyze kitchen wastewater.
The present invention is characterized in that a power supply unit for each electrode of the first electrolytic unit and the second electrolytic unit is provided with a circuit for converting the polarity of the electrode.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an overall configuration diagram of a kitchen drainage oil / water separation device showing one embodiment of the present invention, and FIG. 2 is a plan cross-sectional view of a main part of the electrolytic portion. In FIG. 1, reference numeral 10 denotes an oil-water separator, and the tank body 1 is divided into a partition plate 7 having an opening 9 and a partition plate 8 having an opening 11, and is partitioned in the longitudinal direction. An electrolytic processing chamber 3 and an outflow chamber 4 are formed.
5 is an inlet of the inflow chamber 2 and 6 is an outlet of the outflow chamber 4. A basket 17 is disposed inside the inflow chamber 2 to remove the mess of kitchen drainage. The electrolytic processing chamber 3 includes a first electrolytic unit 12 having a dissolving electrode of aluminum or iron, which is a divalent or trivalent metal, and a second electrolytic unit 1 having a dissolving electrode of copper.
And an outlet tube 4 is provided in the outflow chamber 4 and connected to the outlet 6. Each of the melting electrodes is formed in a rod shape or the like.

The kitchen wastewater contains fats and oils, fats and oils emulsified by micelles with a surfactant, and the like. After separating and collecting the contaminants, the contaminants flow into the electrolytic processing chamber 3 communicated with the opening 9.
Subsequently, the current flows into the first electrolysis unit 12 to perform electrolysis by applying a direct current, and the surface is charged negatively (minus) by the generation of positively (positively) charged divalent or trivalent metal ions from the anode side. Emulsified oil droplets are neutralized electrically and destroyed. When the micelles are destroyed, the emulsified fats and oils that have bound the surfactant lose their binding partners, return to the original fats and oils, become apparent, and float due to the difference in specific gravity. Aluminum or iron ions from the anode eventually combine with hydrogen and oxygen in the water to form hydroxides, such as aluminum hydroxide and iron hydroxide, by using fine bubbles of hydrogen and oxygen gas and insoluble pollutants (scum). ) And floated. The floating scum such as oils, hydroxides, food debris, etc. is physically removed manually or by a commonly used method such as a scum skimmer (not shown). In addition, kitchen wastewater can promote the electrolysis reaction because it contains a large amount of salt which is an electrolyte.

Furthermore, kitchen wastewater contains a large amount of organic substances, and is easily rotted by bacteria, particularly in summer, thereby generating a bad smell. The wastewater also flows to the second electrolysis unit 16 provided in parallel with the first electrolysis unit 12, and is similarly electrolyzed. Copper ions from the anode side sterilize anaerobic sulfate-reducing bacteria belonging to a family of putrefactive bacteria. Thus, the generation of offensive odor due to putrefaction is prevented.

The treated water subjected to oil-water separation in the electrolytic treatment chamber 3 flows into the outflow chamber 4, passes through the insertion pipe 18, and is transferred from the outlet 6 to the next step. The insertion end of the insertion pipe 18 is positioned below the water level in the tank 1, and only the treated water containing no scum flows to the outlet 6, so that the oil / water separation operation can be made effective. The water level in the tank body 1 is adjusted by a water level adjuster (not shown) provided inside or outside the tank body 1 so that the flow rate of the oil-water separator 10 can be adjusted, and the oil-water separation operation by the electrolysis reaction can be performed. Can be optimal.

FIG. 2 shows an embodiment of the first electrolysis section 12, in which an electrode 15 provided with an anode and a cathode is provided with a cylindrical guide tube 13 made of vinyl chloride or the like having a plurality of holes 14 opened. It is arranged inside. In addition, the guide tube 1
The upper end and the lower end of the opening 3 are opened to regulate the flow of the drainage together with the hole 14 to ensure the electrolytic reaction, and to insulate the first electrolytic unit 12 to make the manual operation safe. Again, in FIG. 1, reference numeral 19 denotes a power supply unit, and the AC power supply performs AC-DC conversion by a rectifier and connects the first electrolytic unit 12 and the second electrolytic unit 16 to each other.
Each supplies a direct current. Further, the first electrolytic unit 12 and the second
A circuit is provided for automatically changing the polarity of each electrode of the electrolytic section 16 periodically. The above circuit can avoid the necessity of frequent electrode replacement due to the dissolving electrode being worn by melting.

[0010]

Next, the specifications of the oil / water separator according to the present invention and the oil / water separation performance obtained thereby will be specifically described. Electrode output: DC24V 5A (120Wh) Aluminum electrode: 15mm diameter x 167mm length 9 pieces (4A) Copper electrode: 15mm diameter x 167mm length 4 pieces (1A) Processing amount: 200 l / h

Table 1 shows the results of oil-water separation of kitchen wastewater using the apparatus and method described above.

[0012]

Table 1 Before treatment After treatment pH 5.9 6.7 BOD 378 mg / l 128 mg / l COD 140 mg / l 25 mg / l SS 410 mg / l 13 mg / l Normal hexane value 350 mg / l Less than 1.0 mg / l Total bacteria Number 3 × 10 ⁷ cells / ml 3 × 10 ⁵ cells / ml Sulfate-reducing bacteria Medium contamination Not detected Copper ion concentration 0 ppm <3 ppm

[0013] The oil-water separation treatment by the electrolysis described above not only normal hexane value but also SS, BOD, COD.
Was significantly reduced, and the pH was also confirmed to be improved. In addition, it was confirmed that sulfate-reducing bacteria, a sulfide-producing bacterium of the family of anaerobic putrefactive bacteria (soil fungi), were killed, and the copper ion concentration cleared the regulation value for draining to sewer mains. Has been confirmed. Electricity consumption was also small, about 120 Wh. The removal of scum was manually performed two or three times a day.

[0014]

As described above, the method and apparatus for separating oil and water from kitchen wastewater according to the present invention floats and separates emulsified fats and oils by electrolysis using aluminum or iron and copper dissolving electrodes, as well as putrefactive bacteria. Sterilization and generation of offensive odor can be prevented. It is easy to remove the scum that has surfaced, the equipment cost is low, the space required is small, the operation can be performed with low electricity consumption and high removal efficiency, and kitchens from restaurants and canteens etc. It can be used for drainage and has excellent effects such as improved operability, environmental protection, and convenience.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an oil / water separation device for kitchen drainage showing an embodiment of the present invention.

FIG. 2 is a plan cross-sectional view of a main part of the electrolysis unit.

[Explanation of symbols]

 Reference Signs List 2 inflow chamber 3 electrolytic treatment chamber 4 outflow chamber 10 oil / water separator 12 first electrolysis section 15 electrode 16 second electrolysis section 19 power supply section

Claims (6)

[Claims] In a method of separating oil from a kitchen wastewater containing an oil and fat component and an oil and fat component emulsified by a surfactant, a first electrolytic portion having a divalent or trivalent metal as a dissolving electrode and copper as a dissolving electrode. An oil-water separation method for kitchen wastewater, wherein the wastewater is electrolyzed by a second electrolytic part. 2. An oil / water separator for kitchen wastewater containing oils and fats and oils and fats emulsified by a surfactant, comprising: an inflow chamber into which the wastewater flows, and a divalent or trivalent water adjoining the inflow chamber. An electrolytic processing chamber for dissolving the wastewater from the inflow chamber by disposing a first electrolytic section using metal as a melting electrode and a second electrolytic section using copper as a melting electrode; and an electrolytic processing chamber adjacent to the electrolytic processing chamber An oil / water separation device for kitchen drainage, comprising an outflow chamber for discharging treated water from a kitchen. 3. The method according to claim 1, wherein the first electrolytic unit uses aluminum or iron as a melting electrode. 4. The apparatus according to claim 2, wherein the first electrolysis unit uses aluminum or iron as a melting electrode. 5. The kitchen drainage according to claim 1, wherein the first electrolysis section and the second electrolysis section each perform a polarity conversion on the respective electrodes to electrolyze the kitchen drainage. Oil-water separation method. 6. The power supply section of each electrode of the first electrolytic section and the second electrolytic section is provided with a circuit for converting the polarity of the electrode. Oil / water separator for kitchen drainage.