JP5270247B2 - Wastewater treatment facility at food processing plant - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wastewater treatment equipment having a separation tank capable of efficiently removing an oil component and water-insoluble substance or the like in wastewater as oil-containing scum without excessively adding pressure water to wastewater and having a simple tank structure. <P>SOLUTION: The wastewater treatment equipment is constituted so that a vicinity of a treated water takeout port carries a scum feed-out means for scooping up the oil-containing scum to feed it out and a vertical partition plate changing the flow direction of treated water which undergoes the flocculation treatment of the oil component and the water-insoluble substance and includes an opening end part for forming a bent water passage in the separation tank, thereby keeping a bent water passage, through which the treated water subjected to the flocculation treatment of the oil component with the water-insoluble substance flows toward the treated water takeout port, demarcated up to the vicinity of the treated water takeout port from a communication port by the partition plate. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

The present invention, oil in the waste water and the water-insoluble substance: the (floating suspended solids less schematic 2 m m size), etc., relates to a wastewater treatment facility which can be efficiently removed as oil-containing scum, particularly oil The present invention also relates to a wastewater treatment facility suitable for a food processing plant as a pretreatment device for oil-containing organic wastewater containing a large amount of water-insoluble substances.

Conventionally, it is known that water treatment of organic wastewater is performed using a microbial carrier. For example, organic wastewater such as household wastewater, agricultural settlement wastewater, and industrial wastewater can be treated with wastewater treatment facilities using microbial carriers after absorbing load fluctuations in the storage tank (Patent Literature). 1).
FIGS. 5A and 5B show a wastewater treatment facility using the microorganism carrier tank described in Patent Document 1. FIG. The water treatment flow of organic waste water will be described with reference to FIG.

  The discharged organic waste water is once received in the storage tank 30 to absorb the load fluctuation, and then sent to the treatment tank composed of the denitrification tank 40 and the nitrification tank 50. The denitrification tank 40 performs a denitrification process under anaerobic conditions, and the nitrification tank 50 performs a decomposition process of BOD (Biochemical Oxygen Demand) components and a nitrification process of ammonia nitrogen under aerobic conditions. The air diffuser 34 provided at the bottom of the nitrification tank 50 is a means for supplying oxygen necessary for biological treatment by microorganisms. The denitrification tank 40 and / or the nitrification tank 50 is filled with a microorganism carrier (not shown).

As described above, after denitrification treatment and nitrification treatment are performed on the organic waste water, the sludge is settled and separated in the settling tank 60 to obtain treated water. The treated water is discharged into the sewer.
In FIG. 5B, the microbial carrier 31 in the denitrification tank 40 is made to flow with the stirring device 33 provided at the bottom thereof, and is also made to flow with the circulating liquid sent from the nitrification tank 50. The equipment was shown. In the figure, the screen 32 is a means for removing large oil and water-insoluble substances, and the screen 35 is a means for preventing the microbial carrier 32 from flowing out by the flow.

However, if oil-containing organic wastewater containing a large amount of oil is not pretreated and treated with the above-described wastewater treatment equipment, the oil in the wastewater adheres to the microorganism carrier, and biological treatment by microorganisms is significantly hindered. The problem arises. For this reason, the pre-processing apparatus which isolate | separates and removes the oil content in waste_water | drain as oil-impregnated scum efficiently is needed.
For example, a pressurized flotation separation device is known that allows fine bubbles to adhere to oil and water-insoluble substances in waste water and remove them as oil-containing scum (Non-Patent Documents 1, 2, and 3). FIG. 7A shows an example of the structure of the pressure levitation separator 70, and FIG. 7B shows the operation at the drainage inlet 71 in the apparatus. In FIG. 7A, 76 is a drainage inlet, and 77 is a pressurized water inlet.

Also, a wastewater treatment facility has been proposed that removes oil as oil-containing scum from wastewater containing oil at a high concentration as an oil-in-water emulsion (Patent Document 2). As shown in the water treatment flow of FIG. 6, the wastewater treatment facility described in Patent Document 2 includes primary and secondary flocculation reaction tanks using different polymer flocculants, and a pressurized flotation separation tank. Yes.
Patent No. 3730367 JP 2005-246219 A Kurita Kogyo, "A well-understood water treatment technology", published by Nihon Jitsugyo Publishing Co., Ltd., June 2006, p78-79 Ide Tetsuo, "Water Treatment Engineering (Theory and Application)", Gihodo Publishing Co., Ltd., June 1976, p86-91 (Environmental Environmental Management Association), “New Pollution Prevention Technology and Regulations”, Maruzen Co., Ltd., January 2006, p.

Examples of the flocculant used in the flocculation reaction tank include an inorganic flocculant, a cationic polymer flocculant, and an anionic polymer flocculant. Usually, two kinds of these flocculants are used, and the oil and water-insoluble substances in the waste water are removed as oil-impregnated scum by performing the flocculation process in two stages.
For example, in the case of Patent Document 2, a cationic polymer flocculant is used for the primary agglomeration treatment, and an anionic polymer flocculant is used for the secondary agglomeration treatment. An anionic polymer flocculant is used for the inorganic flocculant and the secondary flocculant treatment. Using different types of flocculants in this way, agglomeration treatment is performed in two stages by forming a small floc by the primary agglomeration reaction, coarsening it by the secondary agglomeration reaction, and a large floc with a small amount of flocculant It is for forming. In this primary agglomeration reaction, a flocculant for reacting an oil component and a water-insoluble substance having a size of approximately 2 mm or less with a flocculant to form a small floc is formed in the subsequent secondary agglomeration treatment. A flocculant for forming large flocs is added to the drainage respectively.

The problems of the wastewater treatment facility that performs the agglomeration treatment in two stages are listed below.
(1) In order to remove the oil to the extent that the treated water (clarified liquid) that can be discharged into public water areas and sewers or the biological treatment in the subsequent stage is not significantly hindered, the oil content is reduced in a pressurized flotation tank with a complicated structure. Must be removed (see FIG. 7A).
(2) Since the aggregation treatment is performed in two stages, it is necessary to add the aggregating agent in two steps of the primary aggregation reaction and the secondary aggregation reaction.
(3) In the wastewater treatment facility described in Patent Document 2, primary and secondary agglomeration reaction tanks to which different polymer flocculants are added and a pressurized flotation separation tank are required, and although not shown, they are added in the agglomeration reaction tank The tank structure of the scum flotation separation tank that floats and separates the floc produced by reacting the flocculant, oil, and water-insoluble substance as oil-containing scum becomes complicated.
(4) When the pressurized flotation separation device 70 shown in FIG. 7 (a) is used as a pretreatment device for a wastewater treatment facility equipped with a microorganism carrier tank, pressurized water is added to the wastewater, so that biological treatment is performed. Increased water treatment volume.

7 (a) and 7 (b), the tank structure of the pressurized flotation separation device 70 and the action of flotation / separation using oil-containing / water-insoluble substances 80 in the drainage as oil-impregnated scum will be described.
A drainage inflow part 71 for attaching air bubbles to water-insoluble substances in the drainage is disposed in the center of the tank, and a driving device that rotates a skimmer blade 72 that is a means for collecting the oil-impregnated scum that floats above the tank It is arranged.

Furthermore, in the tank of the separation tank, a space (upper right part in the tank) where the oil-impregnated scum partitioned by the inclined plate 73 is dropped is formed, and oil and water-insoluble substances 80 in the drainage are removed as oil-impregnated scum. A water collection chamber 74 for collecting the treated water after this is formed around the bottom of the tank.
In the drainage inflow portion 71, the oil 80 is adhered to the fine bubbles 81 generated from the jetted pressurized water. Similarly, the water-insoluble substance 80 is attached to the fine bubbles 81. Next, the oil component / water-insoluble substance 80 in the drainage is floated as an oil-impregnated scum on an upward flow as indicated by an arrow in the center of the tank. A downward flow as indicated by an arrow occurs around the inside of the separation tank. Then, the treated water collected in the water collecting chamber 74 around the tank bottom is taken out via the treated water outlet 75.

In view of the above-mentioned problems of the prior art, the present invention can efficiently remove oil and water-insoluble substances in the drainage as oil-impregnated scum without adding pressurized water to the drainage and has a simple tank structure. It is the first object to provide a food processing factory wastewater treatment facility having a separation tank.
A second object is to provide a food processing factory wastewater treatment facility suitable as a pretreatment device for oil-containing organic wastewater containing a large amount of oil and water-insoluble substances.

  Furthermore, since the tank structure is complicated in the prior art, the initial cost for the equipment and the running cost for chemicals, electricity bills, and the like are high, so the third object is to reduce the water treatment cost.

  As a result of intensive studies on wastewater treatment equipment that efficiently removes oil and water-insoluble substances in wastewater as oil-containing scum, the present inventors have used a polymer flocculant as described in Patent Document 2. After the oil is agglomerated, it is efficient to separate and separate the oil and water-insoluble substances in the wastewater as oil-impregnated scum. It was found that the above problem can be solved by forming a bent water channel through which treated water that has been subjected to agglomeration treatment of oil and water-insoluble substances toward the water outlet, and the present invention has been made based on this finding. It was.

That is, the present invention is as follows.
[Claim 1] Having a stirrer in the tank and taking in wastewater containing oil and water-insoluble substances from the drainage inlet, the polymer flocculant added by the polymer flocculant adding means, A flocculation tank that reacts with water-soluble materials to perform a flocculation process, and a separation process that floats and separates the floc formed by the flocculation process as an oil-impregnated scum that communicates with the flocculation tank through a communication port, A food processing factory wastewater treatment facility having a separation tank for removing only treated water after removing the oil and water-insoluble substances as oil-containing scum from the treated water outlet,
The process water taking near the outlet, a scum discharge means for unloaded scooped the oil-impregnated scum, said in a bath of the separation tank, the change of oil and the flow direction of the treated water subjected to coagulation treatment of water-insoluble material A vertical partition plate having an open end that is a water channel bent in a plane parallel to the bottom surface of the separation tank, and the treatment is performed between the communication port and the vicinity of the treated water outlet by the partition plate. water taking Ri Na and waterways bent in a plane parallel to the bottom of the separation tank the process water flows subjected to coagulation treatment of oil and water-insoluble substance is formed toward the exit, the communication ports and the treated water The take-out port is formed by an overflow weir utilizing a head difference as a mechanical transfer means, and the scum carry-out means is constituted by a long cloth filter and a rotation means for repeatedly rotating the filter, and the separation tank Is bent Corresponding to the corner portions of the waterway, the tank bottom inside of a portion the oil-containing scum accumulates locally, established the aeration device for ejecting air, food processing plants wastewater characterized by being connected to the aeration blower Processing equipment.
Stirrer provided in claim 2 wherein the coagulation tank in the tank, the aeration device for injecting air according to claim 1, characterized by being connected to the aeration blower is provided the aeration device in Tank bottom food processing plant waste water treatment plant according to.
The operation of claim 3 wherein the aeration device, food processing plant wastewater treatment facility of claim 1 or 2, characterized by being configured to intermittently performed.
[ 4] The food processing factory wastewater treatment facility according to any one of [1] to [ 3] , wherein the polymer flocculant addition means is capable of adjusting the addition amount.
Claim 5 wherein the polymeric flocculant means, food processing plants wastewater according to any one of claims 1 to 4, characterized in that for setting the amount and density based on the state of the flocs formed Processing equipment.
Claim 6, wherein the polymeric flocculant means addition port, along with the plurality of locations located on either the top or the bottom of the tank, according to claim 1 to 5, characterized in that setting the amount of addition of each individual The wastewater treatment facility of any one of the food processing factories .
7. The polymeric flocculant means, food processing plant wastewater treatment facility according to any one of claims 1 to 6, characterized in that consist of water pipe and a metering pump and flocculant reservoir.
8. The polymeric flocculant means, food processing plants wastewater according to any one of claims 1 to 7, characterized in that configured in coagulant reservoir and distribution pipes and the metering pump and the electric valve Processing equipment.
Food processing plants wastewater treatment facilities according to any one of claims 1-8, characterized by using as a wastewater treatment facility before processing apparatus comprising according to claim 9 microbial carrier vessel.

ADVANTAGE OF THE INVENTION According to this invention, the food processing factory waste water treatment facility with the simple tank structure of a separation tank which can remove efficiently the oil content and water-insoluble substance in waste_water | drain as oil-containing scum can be provided. In addition, since this wastewater treatment facility can efficiently remove oil and water-insoluble substances in the wastewater without adding pressurized water, it is suitably used as a pretreatment device for wastewater treatment facilities having a microorganism carrier tank. be able to. Moreover, since the tank structure has a simple separation tank, the water treatment cost can be reduced.

The present invention will be described below with reference to the drawings.
FIG. 1 is an overall configuration diagram when the wastewater treatment facility shown in FIG. 2 is used as a pretreatment device for a wastewater treatment facility including a microorganism carrier tank. FIG. 2 is a cross-sectional view showing a main part of the wastewater treatment facility according to the embodiment of the present invention, and FIG. 3 takes out only treated water after removing oil and water-insoluble substances in the wastewater as oil-containing scum. It is a longitudinal cross-sectional view which shows the treated water extraction exit 9 vicinity.

In FIG. 1, 11 indicates a known screen for removing large oils and water-insoluble substances, ie substances having a size exceeding approximately 2 mm . For example, a wastewater containing substances such as meat pieces, bone pieces, and fats is discharged from a food processing factory. Of these, large ones can be efficiently removed with the known screen 11, but the size is small. Meat pieces, bone pieces, fats, and the like, which are approximately 2 mm or less, are floating in the drainage and are difficult to remove with the known screen 11.

  Therefore, the wastewater treatment facility according to the embodiment of the present invention has a stirrer 3 in the tank as shown in FIGS. 1 and 2, and discharges wastewater containing oil and water-insoluble substances into the drainage inlet 7. A flocculation tank 1 for performing a flocculation treatment by reacting a polymer flocculating agent added by means of a polymer flocculating agent addition means (also simply referred to as a flocculating agent addition means), an oil in waste water, and a water-insoluble substance. The separation tank 2 communicates with the agglomeration tank 1 through the communication port 8 and performs a separation process for floating and separating the floc formed by the agglomeration process of the aggregation tank 1 as an oil-impregnated scum.

A scum carry-out means 4 is arranged in the vicinity of the treated water outlet 9 of the separation tank 2. In addition to these treatment tanks, a flocculant storage tank 12, a drainage storage tank 16, a treated water storage tank 17, and a flow rate adjusting tank 18 are arranged (see FIG. 1).
First, the polymer flocculant which performs the agglomeration treatment of oil and water-insoluble substances in the agglomeration tank 1 will be described. The polymer flocculant stored in the flocculant storage tank 12 is stored in the flocculant tank 1 by means of a polymer flocculant addition means comprising a pipe 26, a metering pump 27, and motor-operated valves 12a, 12b, 12c, 12d. It is preferable to add it into the separation tank 2.

The polymer flocculant used in the present invention is used to form a large floc by reacting with oil and water-insoluble substances present in waste water.
In the present invention, a polymer flocculant having such an action, having a long chain molecular structure, and preferably having a molecular weight in the range of 3 to 8 million is used. Such a polymer flocculant is capable of forming a large floc and is advantageous for performing a separation treatment for floating and separating oil content and water-insoluble substances as waste oil scum (Patent Document 2, Non-Patent Document 2). 3).

  The polymer flocculant is not limited to the cationic system, and experiments are conducted according to the form of oil and water-insoluble substances contained in the waste water, the type of oil and water-insoluble substances, the amount of oil and water-insoluble substances, etc. In order to carry out a more suitable treatment, it is necessary to adjust the concentration to 1 to 2% instead of 0.1 to 0.2%, which is the concentration used in a polymer having a larger molecular weight and a normal polymer flocculant. It is good to adjust.

  In the wastewater treatment facility according to the present invention, after the flocculant 1 having the stirring device 3 in the tank reacts with the polymer flocculant, the oil in the wastewater and the water-insoluble substance, a large floc is generated, In the separation tank 2, a separation process is performed in which the oil and water-insoluble substances in the wastewater are floated and separated as oil-containing scum. That is, in the agglomeration tank 1, the added polymer flocculant and the waste water are uniformly mixed by the stirring device 3 provided in the tank, and the oil and water-insoluble substance in the waste water react with the polymer flocculant. In addition, the treated water subjected to the agglomeration treatment is agitated in order to incorporate oil and water-insoluble substances into the large flocs produced by the reaction.

Therefore, the stirring device 3 provided in the tank of the coagulation tank 1 is an aeration apparatus that blows out air so as to exhibit the above-described action, and an aeration apparatus is provided at the bottom of the tank so as to generate convection. It is preferably connected to the blower 19.
In addition, by providing an aeration device for ejecting air at the bottom of the agglomeration tank 1, the following effects can be exhibited. This action means that if a water-insoluble substance with a specific gravity greater than the oil content is taken into the large flocs produced by the reaction, not only will the rising speed to float and separate as oil-impregnated scum in the separation tank 2 be reduced, but also to the drainage. In comparison, when the specific gravity of the oil-impregnated scum is increased, the separation tank 2 prevents the oil-impregnated scum from being lifted and separated as an oil-impregnated scum. By additionally taking in the air blown from the aeration device into the large flocs generated by the reaction, the specific gravity of the oil-containing scum can be reduced compared to the case where no air is contained, and the oil-containing scum in the tank of the separation tank 2 As a result, the separation process that floats and separates can be performed efficiently.

  The agglomeration treatment for producing a large floc by reacting the polymer flocculant with the oil in the waste water and the water-insoluble substance is mainly performed in the agglomeration tank 1 having the stirring device 3 in the tank, but the separation tank 2 Can also do it. In the separation tank 2, fine adjustment when the polymer flocculant added in the aggregation tank 1 is too small is performed by opening the motor-operated valve 12 d and polymer aggregation into the separation tank 2 through the pipe 26 and the metering pump 27. This is done by adding an agent (see FIG. 2).

Next, a description will be given of a separation process in which the oil and water-insoluble substances in the waste water are floated and separated as oil-containing scum in the tank of the separation tank 2.
The treated water subjected to the coagulation treatment of the oil and the water-insoluble substance flows into the separation tank 2 from the communication port 8. A scum discharge means 4 is disposed in the vicinity of the treated water outlet 9 for taking out only treated water after being removed as oil-impregnated scum.

  By the way, using the buoyancy of the oil-containing scum from the treated water that has been subjected to the coagulation treatment of the oil and water-insoluble substances, the time required to float and separate the oil and water-insoluble substances that have been flocked is It depends on the ascent rate. Therefore, if the experiment was carried out by changing the type of oil and water-insoluble substances in the wastewater, the amount thereof, the type of polymer flocculant used and the amount added, etc., the ascending speed of the oil-containing scum was obtained, and the tank of the separation tank 2 The length of the water channel formed inside can be determined.

  The wastewater treatment facility according to the embodiment of the present invention that realizes this is a coagulation treatment of oil and water-insoluble substances in the tank of the separation tank 2 that performs the separation process of floating and separating the formed floc as oil-impregnated scum. And a vertical partition plate 6 having open end portions 6a, 6b, 6c that change the flow direction of the treated water and bend the water channel. The partition plate 6 extends from the communication port to the vicinity of the treated water outlet 9 by the partition plate 6. In the meantime, a bent water channel is formed in which the treated water subjected to the coagulation treatment of the oil and the water-insoluble substance is formed toward the treated water outlet.

In FIG. 2, 10a, 10b, 10c, 10d, 10e, 10f, and 10g are the flow of treated water subjected to agglomeration treatment that flows through the water channel formed by the vertical partition plate 6 having the open end portions 6a, 6b, and 6c. Indicated the direction.
Here, the vertical partition plate 6 having the open end 6a is arranged in parallel with the front wall of the separation tank 2, and the opposite side is fixed to a partition wall with the aggregation tank 1. In addition, an inverted U-shaped vertical partition plate having an open end 6b is arranged near the rear wall in the tank, and the opposite side is fixed to the right side wall of the separation tank 2 and has the remaining open end 6c. The other side of the vertical partition plate is also fixed to the right side wall of the separation tank 2.

  Thus, since the bent waterway is formed in the tank of the separation tank 2, it is possible to efficiently remove the oil and water-insoluble substances in the drainage as oil-impregnated scum without adding excessive pressure water to the drainage. A wastewater treatment facility having a separation tank 2 that is simple and has a simple tank structure could be realized. However, it is preferable that the partition plate is movable and has a structure in which the installation position can be adjusted depending on the properties of the drainage and the treatment status.

  In addition, the communication port 8 and the treated water outlet 9 are formed by an overflow weir utilizing the head difference, so that the flow rate of water treatment in the treatment tank composed of the flocculation tank 1 and the separation tank 2 is simplified. This is preferable because it can be adjusted. In addition, the separation tank 2 is provided with an aeration device that blows out air at the bottom of the tank corresponding to the corner of the bent water channel, where oil-impregnated scum accumulates locally, and is connected to the aeration blower. This is preferable because it is possible to prevent the oil-impregnated scum from locally accumulating at that location. Further, it is preferable that the aeration apparatus is operated intermittently because the energy used by the aeration blower can be reduced.

As the scum unloading means 4 arranged in the vicinity of the treated water outlet 9 for picking up and carrying out the oil-impregnated scum, a long cloth filter (polyester filter cloth) and a rotating means for repeatedly rotating the filter (conveyor) It is suitable to comprise.
Such a scum carrying-out means 4 is preferable because the oil-impregnated scum W2 can be scooped up and carried out with a long cloth filter. In FIG. 3, W1 shows the treated water after removing the oil-impregnated scum W2. 2a is a pipe for supplying treated water connected to the U-shaped bowl 2b, and 2b is a U-shaped bowl for collecting treated water after the oil-impregnated scum W2 is removed. The scum collection hopper 5 shown in FIGS. 1 and 2 is arranged immediately below where the oil-impregnated scum carried out by the scum carrying-out means 4 falls.

The wastewater treatment facility according to the embodiment described above uses the height energy of the treated water W1 collected by the U-shaped trough 2b, passes through the treated water supply pipe 2a, and is shown in FIG. Is sent to wastewater treatment facilities.
Further, the addition amount of the polymer flocculant can be adjusted by the metering pump 27 constituting the polymer flocculant addition means, and the motor operated valves 12a, 12b, 12c, and 12d are opened and closed depending on the state of water treatment in the waste water. Therefore, it is better to add the flocculant as follows (refer to FIGS. 1 and 2).
(a) When the motor-operated valve 12a is opened, the middle of the pipe connecting the screen 11 and the flocculation tank 1 serves as a flocculant addition port. In this way, the polymer flocculant is added to the pipe connecting the screen 11 and the flocculant tank 1, and the polymer flocculant and the waste water are mixed before reaching the flocculant tank 1.
(b) When the motor-operated valve 12b is opened, the opening end of the pipe that secures a certain height from the drainage surface of the coagulation tank 1 becomes the coagulant addition port. This is an addition method in which the polymer flocculant and the waste water are mixed so as to strike against the drainage surface of the agglomeration tank 1.
(c) When the motor-operated valve 12c is opened, the open end of the pipe extending to the bottom of the coagulation tank 1 becomes the coagulant addition port. An addition method in which a polymer flocculant and waste water are mixed at the bottom of the agglomeration tank 1 by using a plurality of flocculant addition ports at the bottom.
(d) When the motor-operated valve 12d is opened, as shown in FIGS. 1 and 2, the open end of the pipe extending to the bottom of the corner of the separation tank 2 becomes the flocculant addition port. The flocculant addition port to the separation tank 2 has a fine adjustment function when the polymer flocculant added in the flocculence tank 1 is too small, and completely aggregates the unreacted oil and water-insoluble substances. Therefore, an addition method of adding a polymer flocculant to the separation tank 2.
A plurality of flocculant addition ports for adding the polymer flocculant to the bottom of the separation tank 2 are used, or the flocculant addition port is not the bottom of the separation tank 2 but the separation of the oil and water-insoluble substances in the separation tank 2 It can also be set above the treated water surface. However, a flocculant addition port can also be provided in addition to that.

FIG. 8 shows the configuration of a control device that controls the amount of the polymer flocculant that is suitable for use in the present invention. FIG. 9 shows an example of operation of the metering pump of the polymer flocculant adding means shown in FIG. 8, and FIG. 10 shows an example of operation of the conveyor of the scum unloading means shown in FIG. .
After starting the water treatment, the polymer flocculant is operated by stopping and operating the metering pump of the polymer flocculant adding means and the drive motor of the conveyor of the scum unloading means as shown in FIGS. Can be effectively added to stabilize the water treatment performance and reduce the water treatment cost.

  We constructed a wastewater treatment facility that enables water treatment in food processing plants that contain a large amount of oil and water-insoluble substances. As shown in Table 1, the food processing factory effluent contains a large amount of water-insoluble substances in addition to oil.

Therefore, the wastewater treatment facility shown in FIG. 1 was installed as a pretreatment device for the wastewater treatment facility including the microorganism carrier tank 20 shown in FIG.
Main specifications of the constructed wastewater treatment facility Coplanar tank 1 plane dimensions: inner dimension in the left-right direction = 2 m, inner dimension in the front-rear direction = 4 m.
Planar dimension of the separation tank 2: inner dimension in the left-right direction = 4 m, inner dimension in the front-rear direction = 4 m.

In the tank of the separation tank 2, a vertical partition plate 6 having open end portions 6 a, 6 b, 6 c is provided as shown in FIG. .
A bent water channel having a water depth of 3 m and a water channel width of 800 mm was formed by a vertical partition plate 6 provided in the tank of the separation tank. Moreover, the conveyor which stuck the long cloth-like filter (for example, polyester filter cloth) as the scum carrying-out means 4 was provided in the vicinity of the treated water outlet.

As shown in FIG. 3, the lower end of the conveyor is immersed in treated water subjected to oil agglomeration, and the upper end of the conveyor is positioned above the scum recovery hopper 5 to lift up the oil-containing scum and carry it out. The scum unloading means 4 is used.
The constructed waste water treatment facility (invention example) and a conventional example (a general pressurized flotation separation device is installed in place of the waste water treatment facility shown in FIG. 1, and then the microbial carrier tank 20 shown in FIG. 4 is installed. In the case of water treatment using a wastewater treatment facility, the food processing factory wastewater was treated with water, and the water quality of the following treated water was analyzed to compare the water treatment performance.

  Treated water introduced into a wastewater treatment facility having a microorganism carrier tank 20 (in the case of the invention, treated water after being treated with the wastewater treatment facility shown in FIG. 1; The water quality of the treated water after treatment is shown in Table 2, and the quality of the treated water just before it is treated in the wastewater treatment facility having the microorganism carrier tank 20 and discharged into public water areas or sewers is shown in Table 3.

From the water quality analysis results shown in Tables 2 and 3, according to the invention example, oil and water-insoluble substances in the waste water can be efficiently removed as in the conventional example, as shown in Table 3. The quality of treated water that can be discharged into public water areas and sewers was obtained.
Here, BOD: Biochemical Oxygen Demand (biochemical oxygen demand), n-Hex: n-Hexane Extract (the amount of n-hexane extract), the former is the amount of organic matter in the wastewater, the latter is in the wastewater Represents the oil content. In addition, SS: Suspension Solid (amount of suspended suspended solids) represents the amount of water-insoluble substances in wastewater, and COD: Chemical Oxygen Demand (chemical oxygen demand) represents the amount corresponding to the amount of organic matter in wastewater. .
(Configuration of wastewater treatment facility equipped with microbial carrier tank 20: see FIG. 4)
20 a is a microbial carrier in the microbial carrier tank 20. An appropriate screen is installed in the microorganism carrier tank 20 adjacent to the diffuser 25. 21 is an aeration tank, 22 is a contact aeration tank, and an air diffuser 25 is installed at the bottom of the tank. 23 is a sedimentation tank, 24 is a chlorine sterilization disinfection tank. The air diffuser 25 is connected to, for example, the four aeration blowers 19 shown in FIG. 1 and diffuses the inside of the tank with the air sent from the aeration blower 19.

It is a whole block diagram in case this invention is used as the pre-processing apparatus of the waste water treatment facility which comprises a microorganisms carrier tank. It is a cross-sectional view which shows the principal part of the waste water treatment facility concerning embodiment of this invention. It is a longitudinal cross-sectional view which shows the treated water intake vicinity of the processing tank used for this invention. It is a block diagram of the waste water treatment facility which comprises the suitable microorganism carrier tank to which this invention is applied. (A), (b) is a block diagram of the other waste water treatment facility using a microorganism carrier. It is a water treatment flow figure of the wastewater treatment facility using the pressurization flotation separation tank given in patent documents 2. (A) is sectional drawing which shows the structure of an example of a pressurization floating separation tank, (b) is principal part sectional drawing explaining the effect | action. It is a block diagram of the control apparatus which controls the addition amount of a polymer flocculent suitable for use in the present invention. It is a flowchart which shows the operation example of the metering pump of the polymer flocculent addition means shown in FIG. It is a flowchart which shows the operation example of the conveyor of the scum carrying-out means shown in FIG.

Explanation of symbols

W1 treated water (treated water treated with wastewater treatment facility shown in Fig. 1)
W2 Oil-impregnated scum 1 Coagulation tank 2 Separation tank
2a Pipe for treated water supply
2b U-shaped bowl 3 Stirring device (aeration device)
4 Scum unloading means 5 Scum collection hopper 6 Partition plate
6a, 6b, 6c Open end 7 Drainage intake 8 Communication port 9 Treated water intake
10a, 10b, 10c, 10d, 10e, 10f, 10g Flow direction
11 screens
12 Flocculant reservoir
12a, 12b, 12c, 12d Motorized valve for adding polymer flocculant
16 Wastewater storage tank
17 Treated water storage tank
18 Flow adjustment tank
19 Aeration blower
20 Microbial carrier tank
20a Microbial carrier
21 Aeration tank
22 Contact aeration tank
23 Settling tank
24 Chlorine sterilization tank
25 Air diffuser
26 Piping
27 Metering pump
30 Wastewater storage tank
31 Microbial carrier
32 screens
33 Stirrer
34 Air diffuser
35 screen
40 Denitrification tank
50 Nitrification tank
60 Sedimentation tank
70 Pressure levitation separator
71 Drainage inlet
72 Oil-impregnated scum collecting means (clearance blade)
73 Inclined plate
74 Catchment room
75 Treated water outlet
76 Drainage intake
77 Pressurized water inlet
78 Oil-impregnated scum outlet
79 Sludge outlet
80 Oil and water-insoluble substances
81 bubbles

Claims (9)

The tank has a stirrer, and drains containing oil and water-insoluble substances are taken from the drainage intake, and the polymer flocculant added by the polymer flocculant addition means and the oil and water-insoluble materials in the drainage are added. A flocculant tank that reacts with the flocculant and communicates with the flocculant tank at a communication port, and performs a separation process that floats and separates the floc formed by the flocculant process as an oil-containing scum, A food processing factory wastewater treatment facility having a separation tank for taking out only treated water after removing water-insoluble substances as oil-containing scum from a treated water outlet,
The process water taking near the outlet, a scum discharge means for unloaded scooped the oil-impregnated scum, said in a bath of the separation tank, the change of oil and the flow direction of the treated water subjected to coagulation treatment of water-insoluble material A vertical partition plate having an open end that is a water channel bent in a plane parallel to the bottom surface of the separation tank, and the treatment is performed between the communication port and the vicinity of the treated water outlet by the partition plate. water taking Ri Na and waterways bent in a plane parallel to the bottom of the separation tank the process water flows subjected to coagulation treatment of oil and water-insoluble substance is formed toward the exit, the communication ports and the treated water The take-out port is formed by an overflow weir utilizing a head difference as a mechanical transfer means, and the scum carry-out means is constituted by a long cloth filter and a rotation means for repeatedly rotating the filter, and the separation tank Is bent Corresponding to the corner portions of the waterway, the tank bottom inside of a portion the oil-containing scum accumulates locally, established the aeration device for ejecting air, food processing plants wastewater characterized by being connected to the aeration blower Processing equipment. The stirring device is provided in the flocculation tank in the tank, the aeration device for injecting air, according to claim 1, characterized by being connected to the aeration blower is provided the aeration device in Tank bottom Wastewater treatment facility at food processing plant . The food processing factory waste water treatment facility according to claim 1 or 2 , wherein the aeration apparatus is operated intermittently. The food processing factory wastewater treatment facility according to any one of claims 1 to 3 , wherein the polymer flocculant addition means is capable of adjusting an addition amount. The food processing factory wastewater treatment facility according to any one of claims 1 to 4 , wherein the polymer flocculant addition means sets the addition amount and concentration based on the state of the floc formed. The said polymer flocculent addition means sets the addition amount individually, while an addition port is arrange | positioned in multiple places of the upper part or the bottom part of the said tank, The any one of Claims 1-5 characterized by the above-mentioned. Wastewater treatment facility for food processing plant as described in the paragraph. The food processing factory wastewater treatment facility according to any one of claims 1 to 6 , wherein the polymer flocculant adding means includes a flocculant storage tank, a water pipe, and a metering pump. The food processing factory wastewater treatment facility according to any one of claims 1 to 7 , wherein the polymer flocculant adding means includes a flocculant storage tank, a water pipe, a metering pump, and an electric valve. Food processing plants wastewater treatment facilities according to any one of claims 1-8, characterized by using as a pretreatment apparatus wastewater treatment facility having a microbial carrier vessel.

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