JP5367335B2 - Sludge volume reduction device, sludge treatment facility using the same, and sludge volume reduction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate reducing sludge in wastewater, relating to a sludge reducing device, and a sludge treatment apparatus and sludge reducing method, using the sludge reducing device. <P>SOLUTION: The sludge reducing device 1 includes: an injection nozzle 11 for injecting a sludge fluid pressurized by a pressure pump 2; an injection pipe 12 provided downstream of the injection nozzle 11 and having a diameter larger than that of the injection nozzle 11; and a front pipe 14 provided downstream of the injection pipe 12, having a diameter larger than that of the injection pipe 12, and equipped with a cell membrane destroying wall 18 the sludge fluid flowing through the injection pipe 12 collides with. An air inlet 13 is formed between the injection nozzle 11 and the injection pipe 12 capable of introducing air into the injection pipe 12. Inside the injection pipe 12, a tubular power tube 16 having an outside diameter smaller than the inside diameter of the injection pipe 12 is provided almost concentrically with the injection pipe 12, and extending in the longitudinal direction of the injection pipe 12 toward the front pipe 14. The cell membrane destroying wall 18 in the front pipe 14 has a plurality of projections 19 projecting therefrom. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a sludge volume reducing device, a sludge treatment facility using the sludge volume reducing device, and a sludge volume reducing method, and more particularly, to easily solubilize cell membranes of microorganisms contained in sludge in order to reduce sludge volume. The present invention relates to a sludge volume reduction device, a sludge treatment facility using the same, and a sludge volume reduction method.

  Conventionally, biological treatment methods using microorganisms are known as methods for treating sewage such as sewage. In such a treatment method, organic substances in wastewater are decomposed using microorganisms. However, a large amount of excess sludge is generated in the process of decomposition by microorganisms. Such surplus sludge is industrial waste, and it is necessary to reduce the volume of surplus sludge generated as much as possible.

In order to reduce the volume of excess sludge, it is necessary to destroy (solubilize) the cell membrane of microbial cells that constitute the excess sludge. There are various treatment methods such as a mechanical treatment method and a cavitation treatment method as a treatment method for reducing the volume of excess sludge. Among these treatment methods, for example, in the cavitation treatment method, sludge fluid pressurized by a pump is injected and introduced into the volume reduction treatment device, and the fluid is suddenly decompressed in the volume reduction treatment device to generate cavitation. The sludge is solubilized by the impact force applied when the bubbles collapse. Furthermore, a collision plate is provided in the volume reduction processing device, and sludge injected into the volume reduction processing device is made to collide with the collision plate, thereby combining the impact force caused by cavitation and the impact force colliding with the collision plate. The volume of sludge is reduced by a typical action (for example, Patent Document 1).
JP 2007-152268 A

  However, in the cavitation treatment method as described in the above publication, the injected sludge fluid is greatly decelerated by cavitation in the process toward the collision plate, so the impact force that collides with the collision plate is weakened, and the sludge is sufficiently removed. The volume cannot be reduced. Further, when cavitation is used, there is a problem in that the volume reduction treatment device is liable to be broken easily due to the impact force when the bubbles collapse, and the life of the treatment device is short.

  In view of the above problems, the present invention provides a sludge volume reducing device configured to be able to reduce the volume by applying a sufficient impact force to sludge, a sludge treatment facility using the sludge reduction equipment, and sludge reduction. The purpose is to provide a method of inclusion.

  In order to solve the above problems, a sludge volume reducing device according to the present invention includes an injection nozzle that injects sludge fluid pressurized by a pressurizing means (for example, the pressure pump 2 in the embodiment), and a downstream side of the injection nozzle. An injection pipe having a diameter larger than that of the injection nozzle, a collision surface provided on the downstream side of the injection pipe and in contact with sludge fluid flowing through the injection pipe (for example, the cell membrane destruction wall 18 in the embodiment), the injection nozzle and the injection An air introduction port through which air can be introduced into the injection pipe between the pipes.

  Further, in the sludge volume reducing device having the above configuration, a tubular power tube having an outer diameter smaller than the inner diameter of the injection tube is provided in the injection tube substantially concentrically with the injection tube, and the power tube is connected to the injection tube. It is preferable to extend toward the collision surface in the longitudinal direction.

  In the sludge volume reducing apparatus having the above-described configuration, it is preferable that a plurality of protrusions (for example, a cylindrical shape or a triangular pyramid) protruding from the collision surface are provided on the collision surface.

  Moreover, in the sludge volume reduction apparatus of the said structure, it is preferable that the injection pressure of the sludge fluid injected from an injection nozzle is a pressure of 0.7-0.9 MPa.

  On the other hand, in order to solve the above problems, a sludge treatment facility according to the present invention comprises the sludge volume reducing device, a pressurizing means for supplying a fluid to the spray nozzle, and a sludge tank for accommodating the sludge fluid.

  Moreover, it is preferable to provide the sludge solubilization liquid storage tank which stores the sludge solubilization liquid for making the volume reduction of sludge fluid easy in the sludge processing equipment of the said structure.

  On the other hand, a sludge volume reduction method according to the present invention for solving the above-described problems is an injection nozzle that injects the sludge fluid pressurized by the pressurizing means, and is larger than the injection nozzle provided downstream of the injection nozzle. The sludge fluid pressurized by the pressurizing means is provided using a sludge volume reducing device having a diameter injection pipe and a collision surface that is provided downstream of the injection pipe and that collides with sludge fluid flowing through the injection pipe. The volume of sludge is reduced by spraying from the spray nozzle and causing the sludge fluid to collide with the collision surface.

  According to the sludge volume reducing device of the present invention, the sludge treatment facility using the sludge volume reducing method, and the sludge volume reducing method, when the pressure flow injected from the injection nozzle constituting the sludge volume reducing device spreads all over the injection pipe. As a result, the piston is moved at a high speed, and a negative pressure is generated in the injection pipe on the upstream side of the pressure flow. And by this negative pressure, air is naturally sucked into the injection pipe from the air inlet formed in the sludge volume reducing device, and the sludge fluid is pumped toward the downstream side of the injection pipe. As a result, the pressure difference between the upstream side and the downstream side of the injection nozzle is alleviated, so that cavitation does not occur, sludge high-speed fluid does not slow down, and cavitation generates impact force that collides with the cell membrane destruction wall Can be much higher. In addition, since the cavitation does not occur, the device is not destroyed, and the service life of the sludge volume reducing device can be extended as compared with the prior art.

  Moreover, the power tube is provided in the injection pipe of the sludge volume reducing device. As a result, the high-pressure sludge fluid ejected from the ejection nozzle is guided along the power tube without diffusing in the ejection tube to become a rod-like high-speed fluid, and flows downstream while maintaining the high speed, and is positioned forward. Collides with the impact surface with high impact force. As a result, it is possible to reduce the volume of sludge by destroying the cell membrane of microorganisms contained in the sludge with a high impact force.

  If a plurality of protrusions (cylindrical or triangular pyramid) protruding from the collision surface are provided on the collision surface where the sludge fluid collides while maintaining a high speed by the power tube, these protrusions are in the sludge. When the cell membrane of the microorganism collides, the cell membrane is further easily destroyed, and the cell membrane can be efficiently destroyed.

  Furthermore, if sludge solubilizing liquid for softening the cell membrane of microorganisms such as caustic soda and stabilized hypochlorous acid water and sludge to be treated are mixed in advance and sent to the sludge volume reducing device, sludge can be reduced. It is possible to make it easier to reduce the volume of sludge fluid in the container.

  Here, an embodiment of a sludge volume reducing device according to the present invention, a sludge treatment facility using the same, and a sludge volume reducing method will be described. FIG. 1 is a schematic diagram showing the overall configuration of the sludge treatment facility according to the present invention. As shown in FIG. 1, a sludge treatment facility 100 is installed in a sludge volume reducing device 1 for reducing sludge, and pressurizes waste water containing sludge in the sludge tank 3. A pressure pump 2 to be supplied; a sludge tank 3 for storing wastewater containing sludge; and a sludge solubilizing liquid storage tank 4 for storing sludge solubilizing liquid for treating microorganisms contained in the sludge. It has.

  A known pressure pump can be used as the pressure pump 2, and the sludge in the sludge tank 3 to be treated is sucked and pumped to the sludge volume reducing device 1 side. Further, the sludge solubilizing liquid can be sent from the sludge solubilizing liquid storage tank 4 to the sludge tank 3, and the sludge volume reducing device after the sludge and the sludge solubilizing liquid are mixed in the sludge tank 3. Pumped to one side. Although not shown, a necessary and sufficient filter is provided at the suction port of the pressure pump 2 so that the dirt component in the sludge tank 3 is filtered in the previous stage. The sludge sent to the sludge volume reducing device 1 is reduced in volume in the sludge volume reducing device 1, returns to the sludge tank 3 again, and is stored in the sludge tank 3.

  FIG. 2 is an enlarged view showing details of the sludge volume reducing device 1. As shown in the figure, the sludge volume reducing device 1 is connected to a pressure gauge pipe 15 provided on the most upstream side (pressure pump 2 side) where a pressure gauge (not shown) is installed, and a downstream side of the pressure gauge pipe 15. An injection nozzle 11 provided in the injection nozzle installation pipe 17 for injecting sludge fluid pressurized by the pressure pump 2 and connected to the injection nozzle installation pipe 17 and provided on the downstream side of the injection nozzle 11 An injection pipe 12 having a diameter larger than that of the nozzle 11 and a front pipe 14 connected to the downstream side of the injection pipe 12 so as to extend in a direction substantially perpendicular to the longitudinal direction of the injection pipe 12 are provided. The inner diameter of the injection pipe 12 is almost the same from the upstream side to the downstream side.

The injection nozzle 11 is thin on the tip side (downstream side), and is further pressurized when the sludge fluid from the pressure pump 2 passes through the injection nozzle 11, and is about 30 to about 45 m per second (for example, a pressure flow of 5 kg / The velocity at cm ² is 31.30 m / sec, the velocity at a pressure flow of 7 kg / cm ² is 37.04 m / sec, the velocity at a pressure flow of 9 kg / cm ² is 42.00 m / sec, the velocity at a pressure flow of 10 kg / cm ² Is jetted toward the jet pipe 12 at a speed of 44.27 m / sec. The above-mentioned range is preferable as the injection speed injected into the injection pipe 12, but the reason is that if the injection speed is made lower than these speeds, the sludge fluid collides with the front pipe 14 and the volume is reduced. On the contrary, when the injection speed is higher than these speeds, it is necessary to enlarge the apparatus to withstand the impact force applied to the volume reduction device 1, or the apparatus is easily broken by the impact force. . In addition, a known pressure pump that injects sludge fluid with a pressure of 10 kg / cm ² or more is not a general-purpose pump, but an expensive special pressure pump that is difficult to use for general purposes. Not suitable.

  Inside the injection pipe 12, a tubular power tube 16 having an outer diameter smaller than the inner diameter of the injection pipe 12 is provided substantially concentrically with the injection pipe 12. The power tube 16 extends in the longitudinal direction through the inside of the injection tube 12 from the downstream side between injections to the upstream side. With such a configuration, the high-pressure jet flow of the sludge fluid injected from the injection nozzle 11 to the injection pipe 12 is guided along the power tube 16 to become a rod-like high-speed fluid without being diffused, and maintains high speed. While colliding, it collides with the inner wall of the front tube 14 located in front of the injection tube 12. Due to the impact force at this time, the cell membrane of microorganisms in the sludge is destroyed and the volume is reduced.

  The injection nozzle installation pipe 17 between the injection nozzle 11 and the injection pipe 12 communicates with a gap provided between the injection nozzle 11 and the injection pipe 12 and the outside of the sludge volume reducing device 1. 13 is formed. A plurality of the air inlets 13 are annularly arranged on the outer surface of the sludge volume reducing device 1, and the outside air is taken into the injection pipe 12 from here.

  As described above, the sludge flow pumped by the pressure pump 2 is further pressurized by the jet nozzle 11 and jetted vigorously from the jet nozzle 11. When the jet flow from the injection nozzle 11 expands in the injection pipe, the piston moves at a high speed, and a vacuum state is generated on the upstream side of the injection pipe 12. Thus, air is naturally sucked into the injection pipe 12 from the air introduction port 13 by the negative pressure on the upstream side of the injection pipe 12. In this state, the pressure distribution of the high-speed fluid from the upstream side to the downstream side of the injection nozzle is uniform and no portion to be depressurized is generated, so that cavitation does not occur. Therefore, the sludge high-speed fluid is not decelerated, and the impact force that collides with the inner wall of the front pipe 14 is high, so that it is possible to efficiently destroy the cell membrane of microorganisms in the sludge. Moreover, since cavitation does not occur, the sludge volume reducing device 1 is less likely to be broken, and its service life can be extended.

  A cell membrane destruction wall 18 is provided on the inner wall surface of the front tube 14 and on the downstream side in the longitudinal direction of the injection tube 12. The surface of the cell membrane destruction wall 18 is provided with a large number of, for example, columnar or triangular pyramidal projections 19 (for the sake of clarity, the triangular pyramid-like projections 19 are formed on the cell membrane destruction wall 18 in FIG. Exaggerated). As a result, the cell membrane of microorganisms in the sludge fluid that has flowed through the injection pipe 12 at high speed is likely to be destroyed by colliding with the protrusions 19 formed on the surface of the cell membrane destruction wall 18, and efficiently destroys the cell membrane. can do. Further, the inner diameter of the front tube 14 is set to be twice or more the inner diameter of the injection tube 12, whereby the cell membrane destruction wall 18 having a large surface area is installed inside the front tube 14 and sludge that collides with the cell membrane destruction wall 18. It becomes possible to efficiently destroy the cell membrane of microorganisms in the fluid.

  In order to reduce the volume of sludge, the high-speed sludge fluid injected into the injection pipe 12 has only to collide with some means. Therefore, the sludge volume reducing device 1 is limited to the above configuration. Absent. In the above-described embodiment, sludge is collided with the cell membrane destruction wall 18 of the front pipe 14. For example, a collision plate is provided near the downstream outlet of the injection pipe 12 without connecting the front pipe 14 to the injection pipe 12. A configuration in which a high-speed sludge fluid is allowed to collide with the collision plate may be employed. In addition, if it is possible to sufficiently destroy the cell membrane of microorganisms in the sludge, it is not always necessary to form the protrusion 19 on the cell membrane destruction wall 18 surface.

  Furthermore, as described above, the sludge fluid is mixed with a sludge solubilizing solution for softening the cell membrane of microorganisms, and the cell membrane of microorganisms in the sludge fluid that collides with the cell membrane destruction wall 18 is easily destroyed. Yes. As the sludge solubilizing solution, an alkaline solution having a pH of 11 to 12 containing caustic soda or a stabilized hypochlorous acid aqueous solution having a sterilizing effect is preferable, but other solutions may be used.

FIG. 1 is a schematic diagram showing the overall configuration of the sludge treatment facility of the present invention. FIG. 2 is a schematic view showing details of the sludge volume reducing apparatus shown in FIG.

Explanation of symbols

1 Sludge volume reduction device 2 Pressure pump (pressurizing means)
DESCRIPTION OF SYMBOLS 3 Sludge tank 4 Sludge solubilization liquid storage tank 11 Injection nozzle 12 Injection pipe 13 Air inlet 14 Front pipe 16 Power tube 17 Injection nozzle installation pipe 18 Cell membrane destruction wall (collision surface)
19 Protrusion 100 Sludge treatment equipment

Claims (7)

A sludge volume reduction device,
An injection nozzle that injects sludge fluid pressurized by the pressurizing means; an injection pipe that is provided on the downstream side of the injection nozzle and has a larger diameter than the injection nozzle; and the injection pipe that is provided on the downstream side of the injection pipe A collision surface on which sludge fluid flowing through the air collides, and an air introduction port capable of introducing air into the injection pipe between the injection nozzle and the injection pipe ,
Velocity of the sludge fluid injected from the injection nozzle, 30 m / s to 45 m / s der Rukoto apparatus according to claim. Inside the injection pipe, the than the inner diameter of the injection tube outside diameter rather small, and and the inner diameter is larger tubular power tube than the injection nozzle disposed substantially concentrically with the injection tube, the power tube The sludge volume reducing device according to claim 1, wherein the sludge volume reducing device extends in the longitudinal direction of the spray pipe toward the collision surface.   The sludge volume reducing device according to claim 1, wherein the collision surface is provided with a plurality of protrusions protruding from the collision surface.   The sludge volume reducing device according to any one of claims 1 to 3, wherein a spray pressure of the sludge fluid sprayed from the spray nozzle is a pressure of 0.7 to 0.9 MPa.   A sludge volume reducing device according to any one of claims 1 to 4, a pressurizing means for supplying fluid to the spray nozzle, and a sludge tank for storing sludge fluid. Processing equipment.   The sludge treatment facility according to claim 5, further comprising a sludge solubilizing liquid storage tank for storing a sludge solubilizing liquid for facilitating volume reduction of the sludge fluid. A sludge volume reduction method,
An injection nozzle that injects sludge fluid pressurized by the pressurizing means; an injection pipe that is provided on the downstream side of the injection nozzle and has a larger diameter than the injection nozzle; and the injection pipe that is provided on the downstream side of the injection pipe Using a sludge volume reducing device comprising a collision surface on which sludge fluid flowing through the air collides, and an air introduction port capable of introducing air into the injection pipe between the injection nozzle and the injection pipe ,
The sludge fluid pressurized by the pressurizing means is ejected from the spray nozzle at a speed of 30 m / s to 45 m / s, and sludge fluid is collided with the collision surface to reduce the volume of sludge. And how to.

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