JP2009090222A - Apparatus and method for kitchen effluent treatment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a kitchen effluent treatment apparatus and method which can surely purify kitchen effluent with a simple structure. <P>SOLUTION: The kitchen effluent treatment apparatus comprises: a first tank 10 for aerating food effluent discharged from a kitchen or the like and treating it with microorganisms; a second tank 20 communicating with the first tank 10 at the bottom and supplying ozone mixture gas to the microorganism-treated effluent and agitating deposited sludge to perform decomposition by oxidative decomposition treatment and activated sludge treatment; and a third tank 30 communicating with the second tank at the bottom and making the effluent stay for a predetermined time to discharge supernatant water. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a kitchen waste liquid treatment apparatus and a kitchen waste liquid treatment method for treating food waste liquid discharged from a kitchen or the like, particularly waste liquid containing a large amount of oils and fats.

  Conventional water purifiers are mainly large-scale purifiers such as purifiers for purifying urban sewers and factory wastewater treatment, and according to this, processing steps (area), processing time, management The scale of means and operating costs will be large.

  On the other hand, kitchen waste liquid treatment at hotels, restaurants, schools, etc. is mostly very small, and even with large dimensions, the trap volume is within 5 tons (eg, 3.0 L × 1.5 W × 1. 0D Unit: m).

  In such kitchen waste liquid treatment, the treatment process, treatment time, management cost, and operation cost are naturally limited, and unlike a large water treatment plant, a more efficient treatment method is required in a shorter time. . For this reason, purification of the grease trap waste liquid still has various problems.

Conventionally, an enzyme treatment unit that treats fats and oils in kitchen waste liquids such as hotels, restaurants, and tenant buildings with an enzyme agent, and a biological treatment unit that treats organic substances in the waste liquid treated with the enzyme treatment unit with microorganisms attached to a biological carrier Has been proposed (for example, see Patent Document 1).
JP 2004-351303 A

  However, in the conventional example described in Patent Document 1, the organic matter in the waste liquid can be decomposed by microorganisms attached to the biological carrier after treating the fats and oils in the kitchen waste liquid with an enzyme agent. However, there is an unsolved problem that the waste liquid cannot be deodorized and sterilized, and organic substances and other impurities cannot be oxidized and removed, and a complete purification treatment cannot be performed.

  In order to solve this unresolved problem, ozone treatment may be incorporated into the normally open process, but in this case too, a flocculant is injected or a filtration treatment is performed to agglomerate and precipitate the suspended matter in the raw water. In order to achieve this, activated carbon treatment is often performed, or chlorine is separately injected, and there is a new problem that the number of treatment steps increases.

  Accordingly, the present invention has been made paying attention to the unsolved problems of the above-described conventional example, and provides a kitchen waste liquid treatment apparatus and a kitchen waste liquid treatment method capable of reliably purifying kitchen waste liquid with a simple configuration. The purpose is that.

  In order to achieve the above object, a kitchen waste liquid treatment apparatus according to claim 1 includes a first tank for performing a microorganism treatment by aeration of food waste liquid discharged from a kitchen or the like, and a bottom portion with respect to the first tank. A second tank that supplies ozone mixed gas to the waste liquid treated with microorganisms and stirs the deposited sludge to decompose by oxidative decomposition treatment and activated sludge treatment, and communicates with the second tank at the bottom. And a third tank that is allowed to stay for a predetermined time and discharges the supernatant water.

  Further, the kitchen waste liquid treatment apparatus according to claim 2 is configured such that the first tank performs aeration by supplying outside air from an air pump to a pipe having a large number of through holes arranged in a bottom portion. It is characterized by being.

  Furthermore, in the kitchen waste liquid treatment apparatus according to claim 3, in the second tank, the ozone mixed gas in which the ozone generated by the ozone generator is mixed with the air is introduced into the waste liquid through the pipe and released, and the waste liquid is oxidized. It is configured to be disassembled.

  Furthermore, the kitchen waste liquid treatment apparatus according to claim 4 is configured such that the second tank supplies the ozone mixed gas to an ejector and discharges the waste liquid while stirring the waste liquid. It is characterized by.

  Still further, the kitchen waste liquid treatment apparatus according to claim 5 is characterized in that the second tank is configured to discharge the ozone mixed gas from the ejector for a predetermined period by a timer.

  Further, in the kitchen waste liquid treatment apparatus according to claim 6, the timer stops supplying the ozone mixed gas to the ejector when there is no inflow of food waste liquid into the first tank, so that the fine solids in the waste liquid It is configured to precipitate sludge and sludge.

  Furthermore, the kitchen waste liquid treatment apparatus according to claim 7 is configured such that the ejector discharges an ozone mixed gas so as to make the liquid level of the waste liquid ripple so as to destroy a lump of floating scum. Features.

  Furthermore, the kitchen waste liquid treatment method according to claim 8 is a first step of supplying a food waste liquid discharged from the kitchen or the like to the first tank and performing aeration to perform microorganism treatment, and microorganisms in the first step. A second step of supplying the treated waste liquid to the second tank and supplying an ozone mixed gas for a predetermined period and stirring to perform oxidative decomposition treatment and activated sludge treatment; and the waste liquid treated in the second step And the third step of precipitating sludge and discharging the supernatant liquid.

  According to the present invention, food waste liquid discharged from a kitchen or the like is subjected to microbial treatment by aeration in a first tank, and then supplied with an ozone mixed gas for a predetermined period and stirred in a second tank for oxidative decomposition treatment and activity. Since the sludge treatment was performed and then the waste liquid treated in the second tank in the third tank was precipitated and the supernatant liquid was discharged, the effect of reliably purifying the food waste liquid discharged from the kitchen etc. Is obtained.

  Here, in the second tank, the ozone mixed gas is supplied for a predetermined period and the waste liquid is stirred, so that the sludge staying at the bottom is rolled up at the time of discharging the ozone mixed gas, and the oxidative decomposition treatment and the activated sludge treatment are simultaneously performed. be able to. In addition, by discharging the waste liquid so as to make the liquid level undulate when the ozone mixed gas is discharged, the floating scum mass can be destroyed. Further, the waste liquid can be convected and stirred by discharge of the ozone mixed gas, and the waste liquid can be stirred without providing a stirring blade driven by an electric motor or the like. Furthermore, microorganisms can be activated by precipitating fine solids and sludge during a period when the ozone mixed gas is not discharged.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a plan view showing an embodiment of the present invention, and FIG. 2 is a cross-sectional view of FIG. 1, wherein 1 is a kitchen for treating waste food discharged from hotels, restaurants, food processing plants, etc. This kitchen waste liquid treatment apparatus 1 has a tank body 2 having an open upper end with a length L = 1.5 m, a width W = 0.75 m, and a depth D = 0.6 m, for example. The waste water treated in the first tank 10 and the first tank 10 on the right side where the food waste liquid is supplied from the upper end side by the boundary walls 3 and 4 disposed inside the tank body 2 and aeration is performed on the waste liquid. On the other hand, the second tank 20 at the center that discharges ozone mixed gas to perform oxidative decomposition treatment and activated sludge treatment and the third tank 30 on the left side that precipitates the waste liquid treated in the second tank and discharges the supernatant liquid are formed. Has been.

  The first tank 10 and the second tank 20 are communicated with each other via a communication portion 5 formed at the lower end portion of the boundary wall 3. Similarly, the second tank 20 and the third tank are formed at the lower end of the boundary wall 4. The communication unit 6 communicates with each other.

  The first tank 10 is formed in a rectangular parallelepiped shape from a rectangular bottom plate portion 10a and side plate portions 10b to 10e suspended from four sides of the bottom plate portion 10a. A waste liquid supply port 12 through which food waste liquid is supplied through the pipe 11 is formed at the rear end side at the upper end of the side plate portion 10c, and food waste mixed in the food waste liquid is formed slightly below the waste liquid supply port 12. A relatively large mesh basket 13 having an open upper end that accommodates solid matter is disposed, and an aeration pipe 14 that performs aeration with a hole for discharging air as a bubble is laid on the bottom plate 10a. It has a configuration.

  Here, as shown in FIG. 1, the aeration pipe 14 includes pipe portions 14 a and 14 b extending along the side plate portions 10 b and 10 d of the first tank 10 while maintaining a predetermined distance therebetween, and the pipe portions 14 a and 14 d. Pipe portions 14c and 14d that communicate with both end portions of 14b and extend along the side plate portions 10c and 10e while maintaining a predetermined distance between them, and a pipe portion 14a that maintains a predetermined distance between the pipe portions 14c and 14d. And 14b and 14f communicating in parallel with 14b. And the pipe part 14b is connected to the external compressed air supply source 24 via the air supply pipe 14g.

  In the first tank 10, the waste liquid (organic matter) is decomposed by the microorganisms in the tank, and aeration is performed to promote the decomposition activity of the microorganisms. As a result, the organic suspended matter containing fats and oils is decomposed and the waste liquid is removed. Purified. Further, the acid in the waste liquid is removed by aeration, the pH is increased, and the decomposition efficiency can be increased. Here, the flow rate of air supplied to the aeration pipe 14 for performing aeration is set to 40 L / MIN, for example.

  Moreover, the 2nd tank 20 is formed in a rectangular parallelepiped shape with the rectangular-shaped bottom face board part 20a similarly to the 1st tank 10, and the side face board parts 20b-20e suspended from each edge | side of this bottom face board part 20a. ing.

  And the ejector 21 which injects ozone mixed gas upwards in the shape of a jet airflow is arrange | positioned in the upper surface center part of the bottom face board part 20a. This ejector 21 has an ozone mixture in which ozone generated by an external ozone generator 23 via an ozone mixed gas pipe 22 is mixed with high-pressure compressed air generated by a compressed air supply source 24 composed of a compressor, for example. The gas is supplied, and the mixed gas is discharged into the waste liquid at a high speed to break up the scum floating oil (scum) floating on the liquid surface by causing the liquid surface of the waste liquid to ripple. The activated sludge treatment can be performed by winding up the sludge staying at the bottom of the tank 20 and causing it to convect and stir the waste liquid.

  Here, the ozone mixed gas to the ejector 21 has a volume of the second tank 20 with an air flow rate of, for example, 40 L / MIN, and an ozone flow rate of, for example, 400 mg / H that can be purified without killing microorganisms in the waste liquid. Is set.

  In this way, by discharging the ozone mixed gas obtained by mixing ozone and compressed air upward from the ejector 21 in the second tank 20 at a high speed, the residual organic matter is oxidized with strong oxidizing power of ozone. It can be decomposed and the odor can be removed with oxidizing power. Furthermore, ozone can also decompose chlorine and acetone used as food disinfectants in food waste.

  In addition, ozone, as a property, promotes the aggregation of suspended particulate matter, and as a result promotes solid-liquid separation of waste liquid. For this reason, a sediment layer (sludge, sludge) is formed at the bottom of the second tank 20 with the solids and fine particles that settle. 70 to 80% of the sludge is microorganisms, and the period in which the food waste liquid flows into the first tank 10 by the timer to discharge the ozone mixed gas from the ejector 21 in order to promote the sedimentation of the sludge and to increase the growth of the microorganisms. For example, the ozone mixture gas is discharged from 8:00 am to 8:00 pm during the period when the gas does not flow, and the waste liquid is convected during the period when the gas mixture is discharged from the ejector 21 to stir up the sludge at the bottom. As a result, sludge accumulated at the bottom is rolled up, and microorganisms in the sludge can promote organic substance decomposition as an activated sludge process, and more effective purification can be performed. That is, microorganisms necessary for biological treatment are activated from the sludge and are continuously supplied into the waste liquid. In addition, the discharge of the ozone mixed gas is stopped from 8:00 pm to 8:00 am before, and the sedimentation of sludge is promoted during this period to promote the growth of microorganisms.

  Further, the third tank 30 is provided with an aeration pipe 31 at the bottom in the same manner as the first tank 10 described above, and a biological treatment similar to that of the first tank 10 is performed by performing aeration of the processing liquid. The remaining oil and fat content is retained in the upper layer, the sludge is retained in the lower tank, and the supernatant liquid is retained in the intermediate layer. The supernatant retained in this intermediate layer is secured. The liquid is discharged from a discharge port 32 disposed at a substantially central position in the vertical direction.

  The ozone generator 23 and the compressed air supply source 24 are controlled to be in an operating state by a timer 25 from, for example, 8:00 am to 8:00 pm, and are stopped from 8:00 pm to 8:00 am before. Controlled.

Next, the operation of the above embodiment will be described.
The waste liquid supply port 12 of the first layer 10 of the kitchen waste liquid treatment apparatus 1 having the above-described configuration is connected to a food waste liquid discharge port discharged from a kitchen of a hotel or restaurant, a food processing factory, or the like through a conducting portion such as a pipe. To do.

  The operation period during which the food waste liquid is supplied to the waste liquid supply port 12 of the first tank 10 is assumed to be from 8:00 am to 9:00 pm, and the stop period during which the supply of the food waste liquid is stopped is after 9:00 pm In the case of before 8 o'clock, the aeration air supplied to the first tank 10 and the third tank 30 and the ozone mixed gas supplied to the ejector 21 of the second tank 20 are supplied only during the operation period. The timer 25 is set so as to stop the supply of the working air and the ozone mixed gas.

  Therefore, at 8:00 am, when the operation period starts, the food waste liquid is discharged from the kitchens of restaurants, hotels, etc., and this food waste liquid is supplied to the waste liquid supply port 12 of the first tank 10 of the kitchen waste liquid treatment apparatus 1. Is done.

  At this time, due to the operation period, the timer 25 causes the ozone generator 23 and the compressed air supply source 24 to be in an operating state, and the compressed air generated by the compressed air supply source 24 becomes the aeration pipe 14 of the first tank 10 and By being supplied to the aeration pipe 31 of the third tank 30, bubbles are generated in the waste liquid in the first tank 10 and the third tank 30 and aeration is performed.

  At the same time, in the second tank 20, the ozone gas generated by the ozone generator 23 is mixed with the compressed air generated by the compressed air supply source 24 to form an ozone mixed gas, and this ozone mixed gas is the second tank 20. The ozone mixed gas is discharged upward from the ejector 21.

  For this reason, the process shown in the flowchart of FIG. 3 is executed in each of the tanks 10, 20 and 30 of the kitchen waste liquid treatment apparatus 1.

  That is, in the first tank 10, solid matter such as raw garbage mixed in the waste liquid is accommodated in the basket 13, and aeration is performed by air bubbles output from the aeration pipe 14. When the microbial treatment by the microorganisms is performed and the waste liquid is decomposed by bacteria, the acid of the waste liquid is removed, the pH is increased, and the decomposition efficiency can be increased.

  Then, the bacteria-decomposed waste liquid is sent to the second tank 20 through the communication part 5 formed at the lower end of the boundary wall 3, and in this second tank 20, the ozone mixed gas discharged from the ejector 21 is used. In addition, the waste liquid is oxidized with ozone to decompose and decompose residual organic substances, and unpleasant odors can be eliminated with oxidizing power. Furthermore, ozone can also decompose chlorine and acetone used as food disinfectants in food waste.

  In addition, ozone, as a property, promotes the aggregation of suspended particulate matter, and as a result promotes solid-liquid separation of waste liquid. For this reason, a sediment layer (sludge, sludge) is formed at the bottom of the second tank 20 with the solids and fine particles that settle. 70 to 80% of the sludge is microorganisms and promotes sedimentation of the sludge.

  Then, by discharging the ozone mixed gas upward from the ejector 21, the waste liquid is convected and the sludge at the bottom is rolled up and stirred, whereby the sludge accumulated at the bottom is rolled up, and the microorganisms in the sludge are activated. As a sludge process, free oil and fat can be decomposed, the amount of accumulated sludge can be reduced, organic matter decomposition action can be promoted, and more effective purification can be performed. That is, microorganisms necessary for biological treatment are activated from the sludge and are continuously supplied into the waste liquid.

  At this time, microorganisms are exposed to the ozone mixed gas and weaken. However, when the stop period comes after 9 pm after the end of the operation period, the ozone generator 23 and the compressed air supply source 24 are turned on by the timer 25. By stopping, stirring of the waste liquid by the ozone mixed gas discharged from the ejector 21 is stopped. For this reason, the sludge separated and solid-liquid separated into a lump (floc) of fine dust floating in the waste liquid by the coagulation action of ozone is agglomerated and settled on the bottom of the second tank 20, and ozone is not supplied during this time. As a result, microorganisms are propagated.

  Further, the ozone mixed gas is discharged upward from the ejector 21 during the operation period, and the discharged ozone mixed gas causes the liquid surface to ripple, thereby destroying the lump of the oil scum floating on the liquid surface. The oil scum can be reduced, and the organic matter can be quickly decomposed by stirring and mixing by the ejector 21 to reduce most of the floating oil scum and the precipitated sludge sludge. The frequency of separately disposing the precipitated sludge sludge can be significantly reduced. At this time, ozone can also decompose chlorine and acetone used as food disinfectant as a disinfectant.

  The waste liquid further purified by ozone oxidation treatment and activated sludge treatment in the second tank 20 is sent to the third tank 30 through the communication portion 6 formed at the lower end of the boundary wall 4. The aeration is performed by the bubble of compressed air discharged from the aeration pipe 31 during the operation period, the microbial treatment is performed similarly to the first tank 10, and the aeration is stopped during the subsequent stop period. As a result, the separated solids settle to the bottom and the light fats and oils accumulate upward, so that the supernatant liquid is separated from the intermediate layer and discharged from the discharge port 32.

  The supernatant liquid discharged from the discharge port 32 is finally C.I. O. The D value is also low (160 mg / L or less), it is improved a lot and can be safely discharged into a drain pipe.

  Thus, according to the above embodiment, the organic matter in the waste liquid is decomposed by the microorganism treatment by aeration in the first tank 10, and the waste liquid subjected to the microorganism treatment is supplied to the second tank 20, and the ozone mixed gas is supplied from the ejector 21. The residual organic matter can be decomposed effectively by performing ozone oxidation treatment and activated sludge treatment while convection and stirring the waste liquid by discharging upward, and by the coagulation effect by ozone A lump of suspended solids can be made and finally the sedimentation effect can be enhanced. After that, by stopping the discharge of the ozone mixed gas from the ejector 21 at night, the suspended matter is settled to form a sediment layer (sludge, sludge). At this time, 70 to 80% of the sludge is microorganisms, and the precipitation of the sludge can be promoted to promote the growth of microorganisms. Moreover, in the second tank 20, the waste liquid can be stirred by forming a convection heading upward in the central part and downward in the side wall part in the waste liquid by the ozone mixed gas discharged from the ejector 21. Therefore, the running cost can be reduced and the configuration of the apparatus can be simplified.

  In addition, in the said embodiment, although the case where the 1st tank 10, the 2nd tank 20, and the 3rd tank 30 were formed by the boundary walls 3 and 4 was demonstrated, it is not limited to this, The 1st tank 10 The second tank 20 and the third tank 30 may be formed separately and connected to each other.

  Moreover, in the said embodiment, although the case where only one ejector 21 was provided in the bottom part of the 2nd tank 20 was demonstrated, it is not limited to this, A plurality of ejectors according to the volume of the 2nd tank 20 21 may be provided.

  Further, the amount of microorganisms in the first tank 10, the second tank 20, and the third tank 30 is preferably measured periodically and replenished if the amount is not adequate.

It is a top view which shows an example of the kitchen waste liquid processing apparatus by this invention. It is the sectional view on the AA line of FIG. It is a flowchart which shows the kitchen waste liquid processing method.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Kitchen waste liquid processing apparatus, 2 ... Tank main body, 3, 4 ... Boundary wall, 5, 6 ... Communication part, 10 ... 1st tank, 11 ... Pipe, 12 ... Waste liquid supply port, 13 ... Basket, 14 ... Aeration pipe 20 ... 2nd tank, 21 ... Ejector, 22 ... Ozone mixed gas piping, 23 ... Ozone generator, 24 ... Compressed air supply source, 25 ... Timer, 30 ... 3rd tank, 31 ... Aeration pipe

Claims (8)

  A first tank for aerating food waste liquor discharged from a kitchen or the like and treating microorganisms, and an ozone mixture gas is supplied to the waste liquid that has been communicated at the bottom to the first tank and treated with microorganisms. And a second tank that performs decomposition by oxidative decomposition treatment and activated sludge treatment, and a third tank that communicates at the bottom with the second tank and stays for a predetermined time to discharge the supernatant water. Kitchen waste liquid treatment equipment characterized by the above.   The said 1st tank is comprised so that aeration may be performed by supplying external air from an air pump to the pipe which pierced many through-holes arrange | positioned by the bottom part. Kitchen waste liquid treatment equipment.   The second tank is configured to introduce and discharge an ozone mixed gas obtained by mixing ozone generated in an ozone generator into the waste liquid through a pipe and oxidize and decompose the waste liquid. The kitchen waste liquid processing apparatus according to claim 1 or 2.   4. The kitchen waste liquid treatment apparatus according to claim 3, wherein the second tank is configured to supply the ozone mixed gas to an ejector and discharge the waste liquid while stirring the waste liquid. .   The kitchen waste liquid treatment apparatus according to claim 4, wherein the second tank is configured to discharge a mixture of ozone from the ejector for a predetermined period by a timer.   The timer is configured to stop the supply of the ozone mixed gas to the ejector when there is no inflow of food waste liquid into the first tank, and to precipitate fine solids and sludge in the waste liquid. The kitchen waste liquid treatment apparatus according to claim 4, wherein   The said ejector is comprised so that ozone mixed gas may be discharged so that the liquid level of a waste liquid may be ruffled so that the lump of the oil-fat scum may be destroyed. The kitchen waste liquid processing apparatus as described in the item.   A first step of supplying food waste liquid discharged from a kitchen etc. to the first tank and performing aeration to perform microorganism treatment, and a waste liquid treated by microorganisms in the first step to the second tank and mixing with ozone A second step of performing oxidative decomposition treatment and activated sludge treatment by supplying gas for a predetermined period and stirring, and supplying the waste liquid treated in the second step to the third tank to precipitate the sludge and supernatant And a third step of discharging the liquid.