JP4773211B2 - Waste liquid treatment equipment - Google Patents

Description

  The present invention relates to a purification treatment technique for livestock waste liquid generated when a solid-liquid separation process is performed on excreta excreted by livestock.

  Since manure excreted by livestock raised in livestock farms contains high concentrations of fertilizer components and organic matter, it has long been used as fertilizer for agricultural products or soil improvement materials. However, in recent years, the management system of livestock farms has become large-scale, and a large amount of manure is intensively generated from large-scale livestock farms. To do. Conventionally, various proposals have been made regarding the processing technology for such livestock waste liquid.

  As a conventional livestock waste liquid treatment technology, an acidic solution is added to the livestock waste liquid to be treated to coagulate and remove organic matter, and then an alkaline solution is added to precipitate and remove ammonium ions, phosphate ions, etc. (For example, refer to Patent Document 1) Or, by supplying bubbles into livestock waste liquid and increasing the oxygen concentration in the waste liquid and activating microorganisms to decompose organic matter (for example, Patent Documents 2 and 3) See).

JP 2003-334567 A JP 2002-301493 A JP 10-43797 A

  In the case of the “wastewater treatment method and wastewater treatment device” described in Patent Document 1, in addition to the acid solution tank and the alkali solution tank, at least two precipitation tanks are required, so that the entire treatment equipment including piping is complicated. However, it is apt to increase in size, and livestock farms where there is not enough room may not be easily adopted. Moreover, since the usage amount of an acidic solution and an alkaline solution increases with an increase in the amount of waste liquid treated, a large amount of an acidic solution and an alkaline solution are consumed in a large-scale livestock farm or the like. Furthermore, it takes another time to dispose of the chemical-mixed precipitate collected from the precipitation tank.

  In the case of the “sewage treatment method” described in Patent Document 2 and the “animal aeration / stirring device for livestock manure” described in Patent Document 3, the entire waste liquid is agitated by the air bubbles fed into the livestock waste liquid. The solid component is pulverized, and the floating of the solid component may continue for 2 to 3 days, resulting in a delay in processing time.

  The problem to be solved by the present invention is to provide a waste liquid treatment technique that does not require the addition of complicated equipment or chemicals and can shorten the purification treatment time.

The waste liquid treatment apparatus of the present invention includes a first storage tank and a second storage tank that can store a waste liquid, a microbial carrier immersed in the waste liquid in the first storage tank, and a waste liquid in the second storage tank. A microbubble generator immersed in the microbubble generator, a pump for feeding the waste liquid in the first storage tank to the microbubble generator, a gas path for supplying air to the microbubble generator, and the second reservoir A liquid supply path for sending waste liquid in the tank into the first storage tank, and penetrating the bottom of the second storage tank on the base end side of the liquid supply path communicating with the second storage tank By providing an upright vertical portion and using the upper end opening of the vertical portion as a waste liquid introduction port, the waste liquid introduction port of the liquid feeding path is arranged at a position higher than the bottom surface of the second storage tank. .

  In such a configuration, the waste liquid in the first storage tank is sucked with a pump and is supplied to the fine bubble generator immersed in the waste liquid in the second storage tank, and the fine bubbles are passed through the gas path. When air is supplied to the generator, the waste liquid mixed with fine bubbles is supplied from the fine bubble generator into the waste liquid in the second storage tank, so that the amount of dissolved oxygen in the waste liquid in the second storage tank increases. Since the waste liquid in which the amount of dissolved oxygen is increased in the second storage tank is sent into the waste liquid in the first storage tank via the liquid feeding path, the amount of dissolved oxygen in the waste liquid in the first storage tank is also increased. As a result, the microorganisms that inhabit the microorganism carrier immersed in the waste liquid in the first storage tank are activated by obtaining sufficient oxygen, and the organic matter decomposition action is enhanced, so that the organic matter contained in the waste liquid is rapidly decomposed. The waste liquid can be purified. Since this process is performed while circulating the waste liquid between the first storage tank and the second storage tank, the waste liquid stored in the first storage tank is quickly purified over time. In addition, about the microorganisms which inhabit a microorganisms carrier, what exists in the waste liquid which is a process target settles naturally with the start of a process, Therefore It is not necessary to add from the outside.

  Since it has a simple structure consisting of a first storage tank containing a microbial carrier, a second storage tank containing a fine bubble generator having a gas path, a pump, and a liquid supply path, complicated equipment do not need. Moreover, since the organic matter in the waste liquid is decomposed by the action of microorganisms that naturally live on the microorganism carrier, no addition of chemicals is required. Since it is not necessary to provide a settling tank for removing organic matter and the like, the purification treatment time can be shortened.

  Here, as the fine bubble generator, a cylindrical gas-liquid swirl chamber capable of swirling gas-liquid, an air inlet for introducing air from the gas path into the gas-liquid swirl chamber, and a pump A liquid introduction port for causing the waste liquid to be supplied to flow into the gas-liquid swirl chamber and generating a gas-liquid swirl flow in the gas-liquid swirl chamber, and discharging a mixture of fine bubbles generated in the gas-liquid swirl chamber Therefore, it is desirable to have a discharge opening provided at the end in the central axis direction of the gas-liquid swirl chamber.

  While sucking the waste liquid stored in the first storage tank with a pump and feeding it to the liquid inlet of the fine bubble generator immersed in the waste liquid in the second storage tank, the fine bubbles via the gas path When air is supplied to the air inlet of the generator, a gas-liquid swirl flow is generated in the gas-liquid swirl chamber, and a negative pressure cavity is formed near the central axis. This negative pressure cavity is also called vortex cavitation, and gas is instantly dissolved in the liquid at the tip, and undissolved gas is shredded by the gas-liquid swirl flow to generate a large amount of fine bubbles. The waste liquid mixed with the fine bubbles is discharged from the discharge port into the waste liquid in the second storage tank. In the fine bubbles supplied in this way, a gas such as ammonia in the waste liquid in the second storage tank moves from the high-concentration liquid into the gas according to the law of gas-liquid equilibrium. It becomes the fine bubble which collected ammonia in the liquid.

Further, in the waste liquid treatment apparatus of the present invention, a vertical portion that stands up through the bottom of the second storage tank is provided on the proximal end side of the liquid supply path that communicates with the inside of the second storage tank, and the vertical portion By using the upper end opening as a waste liquid introduction port, the waste liquid introduction port of the liquid feeding path is arranged at a position higher than the bottom surface of the second storage tank. By such a configuration, it is supplied to the micro-bubble generator via a pump from a first reservoir, since the liquid surface height of the waste liquid stored in the second storage tank is kept constant, fine The bubble generating function of the bubble generator can be kept constant. In addition, the above-described fine air bubbles that have collected ammonia break up when the waste liquid introduction port overflows and the internal gas is released to the outside of the liquid, so that while removing gases such as ammonia in the waste liquid It becomes possible to feed into the first storage tank.

  In this case, it is desirable to dispose the waste liquid discharge port of the liquid supply path communicating with the inside of the first storage tank in the storage area of the microbial carrier. With such a configuration, since it becomes possible to send waste liquid with an increased amount of dissolved oxygen in the second storage tank to an area close to the microorganism carrier, Abundant oxygen can be supplied, and the organic matter decomposition action can be further enhanced.

  According to the present invention, the livestock waste liquid generated when the livestock manure is subjected to the solid-liquid separation process can be purified in a relatively short time without the need for complicated equipment or chemical addition.

  Hereinafter, a waste liquid treatment apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a vertical sectional view showing a waste liquid treatment apparatus according to an embodiment of the present invention, and FIG. 2 is a partially enlarged view of the waste liquid treatment apparatus shown in FIG.

  As shown in FIG. 1, the waste liquid treatment apparatus 10 of this embodiment is an apparatus used for cleaning livestock waste liquid generated when livestock manure is subjected to solid-liquid separation treatment, and can accommodate waste liquids L1 and L2, respectively. 1st storage tank 1 and 2nd storage tank 2, many microbial carriers 3 immersed in the waste liquid L1 accommodated in the 1st storage tank 1, and waste liquid L2 accommodated in the 2nd storage tank 2 A plurality of fine bubble generators 4 immersed therein, a pump 5 for sucking the waste liquid L1 accommodated in the first storage tank 1 and feeding it to the fine bubble generator 4, and air to the fine bubble generator 4 And a substantially L-shaped liquid feeding path 7 for feeding the waste liquid L2 in the second storage tank 2 into the first storage tank 1.

  The second storage tank 2 is placed on a part of the upper edge of the first storage tank 1, and has a bottomed box shape protruding at a position higher than a part of the bottom 1 b of the inner surface of the peripheral wall of the first storage tank 1. The pump 5 is disposed in the liquid collection part 8. The pump 5 is electrically operated by a commercial power source supplied via a power cord 5b and can be turned on / off by a switch 5a. Between the pump 5 and the fine bubble generator 4, the main transmission is performed. A liquid pipe 11, a switching valve 12, and a plurality of sub liquid feeding pipes 13 branched from the switching valve 12 are piped. A horizontal portion 7h of the liquid supply path 7 is disposed immediately above the bottom portion 1b in the first storage tank 1, and a distal end portion of the horizontal portion 7h is closed by a lid body 7c, and a vertical portion 7v that stands up is provided on the proximal end side. The upper end of the vertical portion 7 v is formed so as to penetrate the bottom portion 2 b of the second storage tank 2 and communicate with the second storage tank 2.

  A plurality of through holes 7b are formed on the upper surface side of the horizontal portion 7h of the liquid supply path 7 disposed in the first storage tank 1 so as to be evenly distributed over the entire upper surface of the horizontal portion 7h. The microbial carrier 3 is accommodated so as to be embedded. In this embodiment, the microorganism carrier 3 accommodated in the first storage tank 1 is a single-grain crushed stone having an outer diameter of about 10 mm to 20 mm, and the type of rock is not particularly limited. These microbial carriers 3 are accommodated to such a depth that the lower half of the liquid collection part 8 is buried. Further, in order to discharge the waste liquid L1 in the first storage tank 1 or to use it for cleaning, a drain pipe 9 with an on-off valve 9a is provided at the lower part of the peripheral wall 1a of the first storage tank 1. ing.

  As shown in FIG. 2, the vertical portion 7v of the liquid feeding path 7 communicating with the inside of the second storage tank 2 is erected through the bottom portion 2b, and the upper end opening thereof is used as a waste liquid introduction port 7a. The introduction port 7 a is arranged at a position higher than the bottom 2 b of the second storage tank 2. The plurality of fine bubble generators 4 arranged in the second storage tank 2 are symmetric with respect to the vertical portion 7v of the liquid feeding path 7 in the region between the bottom 2b and the waste liquid introduction port 7a. It arrange | positions and is latched in the attitude | position which discharges the waste liquid L2 mixed with the fine bubble NB toward the bottom part 2b of the 2nd storage tank 2. FIG. An opening 6 a at the upper end of the gas path 6 erected almost vertically from each of the plurality of fine bubble generators 4 is disposed at a position higher than the upper edge 2 a of the second storage tank 2.

  Moreover, the main liquid supply pipe | tube 11 for supplying the waste liquid L1 in the 1st storage tank 1 attracted | sucked with the pump 5 is branched into the some sub liquid supply pipe | tube 13 in the switching valve 12, and each sub liquid supply is carried out. A tube 13 is connected to each microbubble generator 4. By switching the switching valve 12, the waste liquid L <b> 1 can be supplied to all of the plurality of fine bubble generators 4, or the waste liquid L <b> 1 can be selectively supplied to any one of the fine bubble generators 4.

  Next, the structure and function of the fine bubble generator 4 will be described with reference to FIGS. 3 is a perspective view showing a fine bubble generator constituting the waste liquid treatment apparatus shown in FIG. 1, FIG. 4 is a cross-sectional view taken along line AA in FIG. 3, FIG. 5 is a cross-sectional view taken along line BB in FIG. FIG. 7 is a cross-sectional view in the central axis direction of the fine bubble generator shown in FIG. 3, and FIG. 7 is a view showing a gas-liquid swirl flow generated in the fine bubble generator shown in FIG.

  As shown in FIGS. 3 to 6, the fine bubble generator 4 introduces air from the gas path 6 into the gas-liquid swirl chamber 14 and the substantially cylindrical gas-liquid swirl chamber 14 in which the gas-liquid can swirl. The gas-liquid swirl chamber is made to flow into the gas-liquid swirl chamber 14 with the air introduction port 15 opened in one partition wall 14a in the central axis C direction of the gas-liquid swirl chamber 14 and the waste liquid L1 fed from the pump 5. In order to generate the gas-liquid swirl flow R (see FIG. 7) in the liquid 14, the liquid inlet 16 formed in the peripheral wall 14c of the gas-liquid swirl chamber 14 and the liquid mixed with the fine bubbles NB generated in the gas-liquid swirl chamber 14 And a discharge port 17 provided in the other partition wall 14b in the direction of the central axis C of the gas-liquid swirl chamber 14. The liquid introduction port 16 is formed in the tangential direction of the gas-liquid swirl chamber 14 and can feed liquid into the gas-liquid swirl chamber 14 along a direction that forms a twisted position with the central axis C.

  After setting to the state shown in FIG. 1, when the switch 5 a is turned on to operate the pump 5, the waste liquid L <b> 1 in the liquid collection unit 8 provided in the first storage tank 1 is sucked and the main liquid supply pipe 11. The fine bubble generator 4 is fed through the switching valve 12 and the auxiliary liquid feeding pipes 13. The waste liquid L1 fed to the fine bubble generator 4 flows into the gas-liquid swirl chamber 14 from the liquid inlet 16, and as a result, as shown in FIGS. At the same time, a gas-liquid swirl flow R centered on the central axis C is generated, and at the same time, a cylindrical negative pressure cavity V appears along the central axis C. One end of the negative pressure cavity V is located near the air inlet 15 of the gas-liquid swirl chamber 14, and the other end is located near the discharge port 17 of the gas-liquid swirl chamber 14. In, the end of the negative pressure cavity V is constricted.

  A negative pressure is also generated in the vicinity of the air inlet 15 due to the negative pressure of the negative pressure cavity V appearing in the gas-liquid swirl chamber 14 together with the gas-liquid swirl flow R. Therefore, due to the suction force caused by this negative pressure, the gas path 6 The air in the atmosphere is sucked into the gas path 6 through the opening 6a, and this air continuously flows into the negative pressure cavity V in the gas / liquid swirl chamber 14 to rotate the gas / liquid. A gas-liquid swirl flow R is formed together with the liquid flowing into the chamber 14 (waste liquid L1).

  On the other hand, the air flowing into the negative pressure cavity V from the air introduction port 15 is discharged together with the waste liquid L1 from the discharge port 17 while being entrained in the gas-liquid swirl flow R generated in the gas-liquid swirl chamber 14. At this time, at the end of the negative pressure cavity V on the discharge port 17 side, it is threaded by the gas-liquid swirl flow R to become fine bubbles NB, mixed into the waste liquid L1 forming the gas-liquid swirl flow R, and fine bubbles NB It becomes a mixed fluid and is discharged from the discharge port 17 into the waste liquid L2 in the second storage tank 2. The waste liquid L1 mixed with the fine bubbles NB discharged into the waste liquid L2 diffuses therein, but the dissolved oxygen amount of the waste liquid L2 in the second storage tank 2 increases due to the air brought in by the fine bubbles NB. To do.

  The waste liquid L2 whose dissolved oxygen amount has increased in the second storage tank 2 overflows the upper peripheral edge of the liquid supply path 7 and flows into the waste liquid introduction port 7a, flows down in the vertical part 7v, and then flows into the horizontal part 7h. And is fed into the waste liquid L1 in the first storage tank 1 from the plurality of through holes 7b. Thus, the waste liquid L2 whose dissolved oxygen amount is increased in the second storage tank 2 is supplied to the waste liquid L1 in the first storage tank 1, whereby the dissolved oxygen of the waste liquid L1 in the first storage tank 1 is dissolved. The amount can also be increased. Further, the waste liquid L2 flowing into the waste liquid introduction port 7a and flowing down in the vertical portion 7v comes into contact with the atmosphere during the flow, so that oxygen in the atmosphere dissolves into the waste liquid L2, so that the dissolved oxygen also increases.

  By increasing the amount of dissolved oxygen in the waste liquid L1 in the first storage tank 1, microorganisms living in the microorganism carrier 3 immersed in the waste liquid L1 in the first storage tank 1 can obtain sufficient oxygen, This activates the organic matter decomposition action, so that the organic matter contained in the waste liquid L1 is quickly decomposed and the waste liquid L1 can be purified. If this process is continued, the waste liquids L1 and L2 will be purified while circulating between the first storage tank 1 and the second storage tank 2, so that the waste liquid L1 stored in the first storage tank 1 Is quickly purified over time. Then, when it is confirmed that the waste liquid L1 in the first storage tank 1 has been purified to a predetermined level, the switch 5a is operated to stop the pump 5, and then the on-off valve 9a is opened to treat from the drain pipe 9. The liquid can be discharged.

  The waste liquid treatment apparatus 10 includes a first storage tank 1 in which a microbial carrier 3 is stored, a second storage tank 2 in which a fine bubble generator 4 having a gas path 6 is stored, a pump 5, and a liquid supply path 7. Because it has a simple structure, it does not require complicated equipment. In addition, since the organic matter in the waste liquid L1 is decomposed by the action of microorganisms that inhabit the microorganism carrier 3, it is not necessary to add a drug. Furthermore, since it is not necessary to provide a sedimentation tank for removing organic substances and the like, the purification processing time can be shortened. In addition, the microorganisms which have an organic matter decomposition function inhabiting the microorganism carrier 3 are those present in the livestock waste liquid (waste liquid L1) generated when the livestock manure is subjected to the solid-liquid separation treatment, and the first storage with the waste liquid L1. Since it is brought into the tank 1 and settles in the microorganism carrier 3 as it is, it is not necessary to add from the outside.

  As described above, the waste liquid L1 stored in the first storage tank 1 is sucked by the pump 5 and sent to the liquid inlet 16 of the fine bubble generator 4 immersed in the waste liquid L2 in the second storage tank 2. If air is supplied to the air inlet 15 of the fine bubble generator 4 through the gas path 6 while being supplied, a gas-liquid swirl flow R is generated in the gas-liquid swirl chamber 14 and is near the central axis C. A negative pressure cavity V is formed. This negative pressure cavity V is also called vortex cavitation, and its tip is shredded by the gas-liquid swirl flow R to generate a large amount of fine bubbles NB, and the waste liquid L2 mixed with these fine bubbles NB is discharged to the discharge port. 17 is discharged into the waste liquid L2 in the second storage tank 2. Since the fine bubbles NB that continue to be supplied in this way do not rise in the waste liquid L2 in the second storage tank 2 and remain for a long time, the dissolved oxygen amount of the waste liquid L2 in the second storage tank 2 Can be greatly increased.

  Further, in the waste liquid treatment apparatus 10, as shown in FIG. 2, the waste liquid introduction port 7 a of the liquid supply path 7 communicating with the inside of the second storage tank 2 is arranged at a position higher than the bottom 2 b of the second storage tank 2. Yes. With such a configuration, the liquid level height of the waste liquid L2 stored in the second storage tank 2 is kept constant, so that the fine bubble supply function of the fine bubble generator 4 can be kept constant. . For this reason, the waste liquid L2 in which the amount of dissolved oxygen is increased in the second storage tank 2 can be stably fed into the waste liquid L1 in the first storage tank 1.

  In addition, as a waste liquid discharge port of the liquid supply path 7 communicating with the inside of the first storage tank 1, a large number of through holes 7b are formed on the upper surface of the horizontal portion 7h. Arranged in the receiving area. Accordingly, the waste liquid L2 having an increased dissolved oxygen amount in the second storage tank 2 can be sent to an area close to the microbial carrier 3, and oxygen abundant in microorganisms having an organic matter resolving ability living in the microbial carrier 3. As a result, an excellent organic substance decomposing action can be obtained.

  In addition, since the portion where the through hole 7b is opened is in a state where it is buried by a large number of microorganism carriers 3, the waste liquid L1 in the first storage tank 1 is agitated or waved by the waste liquid L2 ejected from the through hole 7b. There is nothing to do. For this reason, immediately after the start of the processing operation, solids present in a relatively large amount in the waste liquid L1 in the first storage tank 1 do not rise in the waste liquid L1 or make the waste liquid L1 cloudy. Therefore, the organic substance decomposition treatment by the microbial carrier 3 proceeds promptly.

  Furthermore, as shown in FIG. 1, the pump 5 is disposed in a liquid collection unit 8 provided in the first storage tank 1, and the liquid level of the waste liquid L <b> 1 accommodated in the first storage tank 1. In the vicinity, the waste liquid L1 flowing over the upper edge 8a of the liquid collecting part 8 and flowing into the liquid collecting part 8 is pumped up and fed toward the fine bubble generator 4. With such an arrangement, it is possible to prevent solids or the like existing near the upper part of the microorganism carrier 3 from flowing into the liquid collection part 8 together with the waste liquid L1. For this reason, only the waste liquid L1 in a relatively clear supernatant portion circulates, and about 90% of SS (suspended substance) can be removed in about one day after the start of the treatment.

  On the other hand, as shown in FIG. 7, in the fine bubble generator 4, while introducing air from one end of the negative pressure cavity V appearing in the gas-liquid swirl chamber 14, The waste liquid L2 mixed with the fine bubbles NB is discharged in the extending direction. For this reason, the negative pressure cavity V continues to exist stably in the vicinity of the central axis C of the gas-liquid swirl chamber 14, and both end portions thereof are stably positioned in the vicinity of the air inlet 15 and the outlet 17, respectively. Therefore, the negative pressure cavity V does not contact the inner surface of the gas-liquid swirl chamber 14, and the occurrence of cavitation erosion can be avoided. Further, since the fine bubble generator 4 itself has a simple structure in which the air-inlet port 15, the liquid-inlet port 16, and the discharge port 17 are provided in the gas-liquid swirl chamber 14, the handling is easy, and the waste liquid L1 and air Since there is no narrow flow path in which foreign matter that flows in is easily clogged, regular maintenance is also unnecessary.

  In addition, as shown in FIG. 6, the air introduction port 15 opened in the partition wall 14 a of the gas-liquid swirl chamber 14 is disposed so as to protrude inward along the central axis C of the gas-liquid swirl chamber 14. A smoothly continuous concave curved surface 14e is provided between the inner peripheral surface 14d of the swirl chamber 14 and the air introduction port 15. By adopting such a shape, it is possible to prevent the end of the negative pressure cavity V on the air inlet 15 side from moving irregularly, so that the negative pressure cavity V is stable near the central axis C. Can continue to exist.

  Further, as shown in FIG. 6, in the region near the partition wall 14 b of the gas-liquid swirl chamber 14, the preliminary swirl unit 18 having a larger inner diameter than other regions is provided. After rectifying once in the preliminary swirl unit 18, the preliminary swirl unit 18 can flow into the entire gas-liquid swirl chamber 14. As a result, the pressure fluctuation of the waste liquid L1 flowing from the liquid inlet 16 is alleviated. Therefore, the movement of the negative pressure cavity V caused by the pressure fluctuation can be prevented, which is effective in preventing cavitation erosion.

  As shown in FIGS. 6 and 7, in the fine bubble generator 4, since the opening area of the liquid introduction port 16 is larger than the opening area of the discharge port 17, the liquid is supplied into the gas-liquid swirl chamber 14 by the pump 5. The pressure in the gas-liquid swirl chamber 14 increases due to the pressure of the waste liquid L1, and the discharge speed of the fluid (waste liquid L1) mixed with the fine bubbles NB discharged from the discharge port 17 also increases. For this reason, the stirring action with respect to the waste liquid L2 in the 2nd storage tank 2 can also be obtained. Further, as shown in FIG. 2, the plurality of fine bubble generators 4 are arranged with the discharge ports 17 facing the bottom 2b of the second storage tank 2, and the fluid containing the fine bubbles NB is directed toward the bottom 2b. Since it is discharged, a stirring action can be obtained.

  On the other hand, if the opening area of the discharge port 17 is larger than the opening area of the liquid inlet port 16, the solid matter that has entered the gas-liquid swirl chamber 14 via the liquid inlet port 16 is discharged. Since the liquid is quickly discharged from the outlet 17, foreign matter storage in the gas-liquid swirl chamber 14 can be prevented. Further, when the opening area of the discharge port 17 is made larger than the opening area of the liquid introduction port 16, it is easy to remove and remove foreign matters and the like that have entered the gas-liquid swirl chamber 14.

  The waste liquid treatment technology according to the present invention can be widely used in the industrial field for purifying livestock waste liquid generated when solid waste is separated from excreta excreted by livestock.

It is a vertical sectional view showing a waste liquid treatment apparatus which is an embodiment of the present invention. FIG. 2 is a partially enlarged view of the waste liquid treatment apparatus shown in FIG. 1. It is a perspective view which shows the fine bubble generator which comprises the waste liquid processing apparatus shown in FIG. It is the sectional view on the AA line in FIG. FIG. 4 is a sectional view taken along line BB in FIG. 3. It is sectional drawing of the center axis direction of the fine bubble generator shown in FIG. It is a figure which shows the gas-liquid swirl flow which generate | occur | produces in the microbubble generator shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st storage tank 1a Peripheral wall 1b, 2b Bottom 2 2nd storage tank 2a, 8a Upper edge 3 Microorganism carrier 4 Microbubble generator 5 Pump 5a Switch 5b Power cord 6 Gas path 6a Opening 7 Liquid feed path 7a Waste liquid introduction Port 7b Through-hole 7c Lid 7h Horizontal part 7v Vertical part 8 Liquid collecting part 9 Drain pipe 9a Open / close valve 10 Waste liquid treatment device 11 Main liquid feed pipe 12 Switching valve 13 Sub liquid feed pipe 14 Gas-liquid swirl chamber 14a, 14b Partition wall 14c peripheral wall 14d inner peripheral surface 14e concave curved surface 15 air introduction port 16 liquid introduction port 17 discharge port 18 preliminary swirl part C central axis L1, L2 waste liquid NB fine bubble R gas-liquid swirl flow

Claims (3)

A first storage tank and a second storage tank that can store waste liquid, a microbial carrier immersed in the waste liquid stored in the first storage tank, and a fine immersion immersed in the waste liquid in the second storage tank A bubble generator, a pump for feeding waste liquid in the first storage tank to the fine bubble generator, a gas path for supplying air to the fine bubble generator, and a waste liquid in the second storage tank A liquid feed path for feeding into the first storage tank, and a vertical portion standing through the bottom of the second storage tank is provided on the base end side of the liquid feed path communicating with the inside of the second storage tank The waste liquid treatment apparatus is characterized in that the upper end opening of the vertical portion is used as a waste liquid introduction port, whereby the waste liquid introduction port of the liquid feeding path is disposed at a position higher than the bottom surface of the second storage tank .   The fine bubble generator is fed from a cylindrical gas-liquid swirl chamber capable of swirling gas-liquid, an air inlet for introducing air from the gas path into the gas-liquid swirl chamber, and the pump. A liquid inlet for causing the waste liquid to flow into the gas-liquid swirl chamber and generating a gas-liquid swirl flow in the gas-liquid swirl chamber, and the gas for discharging the liquid containing fine bubbles generated in the gas-liquid swirl chamber. The waste liquid treatment apparatus according to claim 1, further comprising: a discharge port opened at an end of the liquid swirl chamber in the central axis direction. 3. The waste liquid treatment apparatus according to claim 1, wherein a waste liquid discharge port of the liquid feeding path communicating with the inside of the first storage tank is disposed in the storage area of the microorganism carrier.

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