JP2002119997A - Method and apparatus for solubilizing sludge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sludge solubilizing method constituted so as to be able to solubilize sludge efficiently by pressing sludge so as to make it easy to destruct cells of microorganisms in sludge and subsequently lowering pressure suddenly and allowing the external force due to a change in flow velocity, or the like, of sludge to act. SOLUTION: In a sludge solubilizing method for eluting components not eluted and contained in cells of microorganisms in sludge by applying external force to the sludge to elute them and solubilizing the same, the sludge D is housed in a pressure container 2 equipped with a press means 6 to be pressed and this pressed sludge D is ejected from a nozzle 7 to be suddenly lowered in pressure and the external force due to the change in the flow velocity of sludge D is allowed act on the sludge D to perform solubilization.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for solubilizing sludge, and more particularly, to a method for reducing the pressure of sludge after pressurizing it and applying an external force due to a change in the flow rate of sludge. The present invention relates to a method and an apparatus for solubilizing sludge in which sludge is effectively solubilized.

[0002]

2. Description of the Related Art Conventionally, an activated sludge treatment method in which organic wastewater such as sewage is biologically treated with microorganisms and discharged as surplus sludge has been adopted. In this activated sludge treatment method, surplus sludge is discharged according to the amount of organic wastewater to be treated, so that it becomes necessary to treat the surplus sludge. In order to solve such problems as a rise in operating costs and a decrease in final disposal sites when disposing of the excess sludge, a solubilization treatment of the sludge in which the excess sludge is not discharged out of the water treatment system has been proposed. As the solubilization treatment, for example, there is a method of solubilizing excess sludge by applying high temperature and high pressure, and a method of solubilizing by applying high pressure a plurality of times at normal temperature has been proposed.

[0003]

However, in the above-mentioned conventional method for solubilizing sludge, the method of solubilizing sludge by applying high temperature and high pressure to the sludge increases energy costs and increases the cost of heaters and heat exchangers. In addition to the cost of the equipment, there is a problem that the running cost is large depending on the degree of temperature rise, and there is also a problem that scale adheres to the inside of the heat exchanger and clogs the piping, making maintenance difficult. Was. In addition, in the method of applying pressure at normal temperature multiple times, the cells of the microorganisms in the sludge are in a state where it is hard to break as much as the high temperature is not applied, and it is possible to increase the solubilization rate by increasing the number of times of applying pressure. However, there is a problem that the solubilization is limited and the solubilization cannot be performed efficiently.

The present invention has been made in view of the above-mentioned problems of the conventional method for solubilizing sludge, and in order to easily break down the cells of microorganisms in the sludge, after the sludge is pressurized, the pressure is rapidly reduced, It is an object of the present invention to provide a method and an apparatus for solubilizing sludge that can efficiently solubilize sludge by applying an external force due to a change in sludge flow velocity or the like.

[0005]

Means for Solving the Problems To achieve the above object, the method for solubilizing sludge of the present invention comprises eluting components that are not eluted contained in cells of microorganisms in sludge by applying an external force, In the method of solubilizing sludge to be solubilized, the sludge is housed in a pressurized container equipped with a pressurizing means and pressurized, and the pressurized sludge is rapidly reduced by ejecting it from a nozzle, The method is characterized by applying external force to the sludge by changing the flow rate of the sludge to solubilize the sludge.

In this method for solubilizing sludge, the sludge is pressurized in a state where the sludge is accommodated in a pressurized container provided with a pressurizing means, so that the sludge can be easily pressurized to a predetermined pressure. By simply ejecting the pressurized sludge from the nozzle connected to the pressurized container, the pressure of the pressurized sludge is rapidly reduced, and the external force of acceleration and deceleration due to the change in the flow velocity of the sludge is applied to the sludge. Work, which
It destroys microbial cells in sludge and solubilizes them.

In this case, a prada can be used as a means for pressurizing the sludge.

[0008] This makes it possible to easily perform appropriate pressurization in accordance with the properties of sludge and the like by the ladder provided in the pressurized container.

Then, the driving fluid filled in the ladder is discharged, and the sludge can be sucked and stored in the pressurized container by utilizing the negative pressure generated by the reduction in the volume of the ladder. .

[0010] Thus, a set required amount of sludge can be sucked and stored in the pressurized container without using a pump.

Further, the sludge can be heated and heated before being stored in the pressurized container.

[0012] Thereby, the cells of the microorganisms in the sludge which are not easily destroyed only by pressurization are easily destroyed by heating, and the synergistic effect of this heating and pressurization enables the sludge to be surely produced regardless of the properties of the sludge. Can be solubilized.

[0013] Further, the solubilization can be performed by the impact force generated by colliding the sludge ejected from the nozzle with the fixed object.

As a result, primary destruction of external force caused by sudden decompression and the like, and flow velocity change (acceleration,
Through the deceleration (acceleration of deceleration) and the secondary destruction of the external force caused by the change in direction, the sludge can be more reliably solubilized.

Further, the solubilization can be performed by the impact force generated by colliding sludge ejected from a plurality of nozzles.

Thus, the sludge can be more surely solubilized through the primary destruction of external force caused by sudden decompression or the like and the secondary destruction due to collision between sludges.

Further, the sludge solubilization apparatus of the present invention is connected to a pressurized container having a pladder for pressurizing the sludge therein and a pressurized container so as to cause the pressurized sludge to cause a rapid pressure drop. And a driving fluid pump unit. The nozzle is configured to form a circuit for selectively pressurizing and depressurizing the ladder.

This sludge solubilization apparatus includes a pladder in a pressurized container, and is provided with a vacuum pump for selectively pressurizing and depressurizing the pladder, and a driving fluid pump unit. Can be reliably accommodated in a pressurized container, pressurized, and supplied to a nozzle by a simple mechanism.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the method and apparatus for solubilizing sludge of the present invention will be described with reference to the drawings.

FIG. 1 shows an example of a sludge solubilization treatment system to which the method for solubilizing sludge of the present invention is applied.

In this sludge solubilization treatment system, a predetermined amount of sludge D discharged from an aeration tank or the like installed in a sewage treatment plant is stored in a sludge storage tank 1. The heater 11 heats the stored sludge D to a temperature at which the cells of the microorganisms in the sludge are easily destroyed.

A sludge supply pipe 31 provided with a supply valve 21 for supplying and stopping sludge is connected to the sludge storage tank 1, and the end of the sludge supply pipe 31 is connected to the pressurized container 2 and the nozzle 7.
It is connected in the middle of the discharge pipe 32 that connects between them. The discharge pipe 32 is provided with the valve 22 on the nozzle 7 side from the position where the sludge supply pipe 31 is connected.

The pressurized container 2 is hermetically sealed and can withstand a predetermined set pressure. As a pressurizing means, a ladder 6 is provided inside the pressurized container 2. This Prada 6
Is connected to a drive fluid pump unit 5 disposed outside the pressurized container 2 via a drive fluid supply pipe 34 so that the drive fluid supply pipe 34 can be expanded and contracted. Are branched off and connected to the accumulator 4. Further, the pressurizing valve 24 is connected in the middle of the driving fluid supply pipe 34, and a prada control pipe 35 having the ladder control valve 23 is provided between the pressurizing valve 24 and the ladder 6. The tip of the prada control pipe 35 is connected to a driving fluid storage tank 30 provided with a vacuum pump 3, and the suctioned driving fluid F is supplied to the driving fluid pump unit 5.
A driving fluid return pipe 36 for returning the fluid to the pump is provided. The driving fluid return valve 25 is connected in the middle of the driving fluid return pipe 36.

The nozzle 7 is installed in, for example, a spray tank 8 so that the pressurized sludge D is not sprayed and diffused to the surroundings.
A discharge pipe 37 is connected to the inner bottom of the spray tank 8, and the cells of the microorganisms in the sludge are destroyed by the external force generated by the sudden decompression or the like by being injected from the nozzle 7, and the solubilized sludge is introduced into the aeration tank 9. It is configured to be returned and biologically treated.

In this embodiment, the nozzle 7
Is formed with a plurality of injection holes, and pressurized sludge injected from the nozzle 7 is rapidly reduced in pressure by being injected, and an external force acts on microbial cells in the sludge by the rapid pressure reduction action. In order to efficiently destroy the cells of the microorganisms in the sludge,
As shown in (b), each nozzle 7 is arranged so that the sludge injected from the nozzles 7 collides with each other.

In addition, pressurized sludge ejected from the nozzle is caused to collide with a fixed object, for example, an impingement plate installed in front of the nozzle, and the impact force of the sludge physically removes microorganisms in the sludge. Cells can be destroyed.

Next, the operation of the method for solubilizing sludge will be described. The sludge D stored in the sludge storage tank 1 is heated by the heater 2 in the sludge storage tank 1 as necessary (it may be not heated depending on the properties of the sludge), and then the pressurized container. 2 housed.

The sludge D is accommodated in the pressurized container 2 by opening the sludge supply valve 21 and filling the pladder 6 in the pressurized container 2 by driving the vacuum pump 3. The sludge is sucked into the pressurized container 2 using the negative pressure generated by reducing the volume of the ladder 6 by discharging the driving fluid that is present, and thereby the pump is inserted into the pressurized container 2. Without using the required amount of sludge in the sludge storage tank 1 via the sludge supply pipe 31 and the discharge pipe 32,
Can be sucked and stored. At this time, the valve 22 is closed so that the sucked sludge is surely introduced into the pressurized container 2.

When the vacuum pump 3 is driven, the pressurizing valve 24 and the driving fluid return valve 25 are closed, and the ladder control valve 23 is opened. The driving fluid F in the ladder 6 is sucked into the driving fluid storage tank 30 via the pipe 35 and the driving fluid supply pipe 34. Next, the driving fluid return valve 2
5 is opened to return to the driving fluid pump unit 5 via the driving fluid return pipe 36. In this way, the required amount of sludge D is accommodated in the pressurized container 1 by contracting the ladder 6.

When the required amount of sludge D is stored in the pressurized container 1, the vacuum pump 3 is stopped, and the supply valve 2 is turned off.
After or simultaneously with closing the 1 and the prada control valve 23, the pressurizing valve 24 is opened. As a result, the driving fluid F stored in the accumulator 4 in advance is introduced into the ladder 6 via the driving fluid supply pipe 34. Thereby, the ladder 6 expands, and the inside of the pressurized container 2 is pressurized.

Next, by opening the valve 22, the pressurized sludge D is injected from the nozzle 7 at the tip through the discharge pipe 32. At this time, the pressurized sludge is suddenly depressurized, and the external pressure acts on the cells of the microorganisms in the sludge, and an external force of acceleration and deceleration due to a change in the flow velocity of the sludge acts on the sludge. Of microbial cells will be destroyed. In this manner, by alternately switching the expansion and contraction of the ladder 6 and combining the opening and closing operations of the respective valves in synchronism with this operation, the sludge D is accommodated in the pressurized container 2 and jetted from the nozzle 7, and the sludge D is injected. Can be continuously solubilized.

In this case, the sludge D injected from the nozzle 7
When is heated by the heater 11, the cells of the microorganisms in the sludge are more easily destroyed by the heating together with the rapid pressure drop due to the injection, and the solubilization is promoted.

Further, solubilization can be promoted by applying a physical impact pressure to the sludge injected from the nozzle 7. As a means for applying the impact pressure, a method of directly colliding sludge ejected from the nozzle 7, a method of ejecting and colliding sludge toward a fixed object, and other methods can be arbitrarily adopted.

The method and apparatus for solubilizing sludge according to the present invention have been described based on the embodiments.
The present invention is not limited to the above configuration, and the configuration can be appropriately changed without departing from the gist of the invention.

[0035]

According to the method for solubilizing sludge of the present invention, a pump is provided by pressurizing a driving fluid which is easily pressurized in a state in which sludge is accommodated in a pressurized container provided with pressurizing means. Since the sludge is pressurized without using a pressurizing means such as abrasion, the sludge can be easily pressurized to a predetermined pressure. Here, when oil that does not cause wear such as a pump is used as the driving fluid, the optimum tens of MP
Pressurization of a can be easily realized by using a general-purpose hydraulic pump. Then, by simply discharging the pressurized sludge from the nozzle connected to the pressurized container, the pressure of the pressurized sludge is rapidly decreased, and the sludge is accelerated and decelerated by the change in the flow velocity of the sludge. By applying an external force of acceleration, the cells of the microorganisms in the sludge can be destroyed, and the solubilization of the sludge can be surely performed by an extremely simple method.

Further, by using a prada as a means for pressurizing the sludge,
Appropriate pressurization according to the properties of sludge can be easily performed.

Then, the driving fluid filled in the ladder is discharged, and the sludge is sucked and stored in the pressurized container by utilizing the negative pressure generated by the decrease in the volume of the ladder. A set required amount of sludge can be sucked and stored in the pressurized container without using a pump.

Further, by heating the sludge before storing it in the pressurized container and raising the temperature, the cells of the microorganisms in the sludge which are difficult to be destroyed only by pressurization are easily destroyed by heating. By the synergistic effect with the pressurization, the sludge can be surely solubilized regardless of the properties of the sludge.

Also, by solubilizing by the impact force generated by colliding the sludge ejected from the nozzle with the fixed object, primary destruction of external force caused by sudden decompression and the like, and collision with the fixed object Through the flow velocity change (acceleration and deceleration acceleration) and the secondary destruction of the external force caused by the change in direction, the sludge can be more reliably solubilized.

Also, by solubilizing by the impact force generated by colliding sludge ejected from a plurality of nozzles, primary destruction of external force caused by sudden pressure reduction and the like, and collision of sludge by sludge are caused. Through the secondary destruction, the sludge can be more reliably solubilized.

Further, according to the sludge solubilizing apparatus of the present invention, a vacuum pump is provided in the pressurized container, and a vacuum pump for selectively pressurizing and depressurizing the plada, and a driving fluid pump unit are provided. The sludge pump that sucks and discharges sludge that can easily be clogged or abraded can be stored in a pressurized container, pressurized, and supplied to the nozzle with a simple mechanism. Becomes unnecessary, and a highly durable sludge solubilizing apparatus can be provided.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a method for solubilizing sludge according to the present invention, in which (a) is a flowchart and (b) is an enlarged explanatory view of a nozzle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sludge storage tank 11 Heater 2 Pressurized container 21 Supply valve 22 Valve 23 Prada control valve 24 Pressure valve 25 Drive fluid return valve 3 Vacuum pump 30 Drive fluid storage tank 31 Sludge supply pipe 32 Discharge pipe 34 Drive fluid supply pipe 35 Prada control Pipe 36 Drive fluid return pipe 37 Discharge pipe 4 Accumulator 5 Drive fluid pump unit 6 Prada 7 Nozzle 8 Spray tank 9 Aeration tank D Sludge F Drive fluid

 ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Hideaki Hamada 3-1-1, Shimosakabe, Amagasaki City, Hyogo Prefecture Inside Hitachi Kiden Kogyo Co., Ltd. (72) Inventor Teruichi Shinfu 3-11 Shimosakabe, Amagasaki City, Hyogo Prefecture No. 1 F-term in Hitachi Kiden Kogyo Co., Ltd. (reference) 4D059 AA05 BF02 BK12 BK30 CB30

Claims (7)

[Claims] 1. A method for solubilizing a sludge, wherein components which are not eluted and contained in cells of microorganisms in the sludge are eluted by applying an external force to solubilize the sludge. The pressurized sludge is ejected from a nozzle to reduce the pressure rapidly, and the sludge is subjected to an external force due to a change in the flow rate of the sludge to solubilize the sludge. How to solubilize sludge. 2. The method for solubilizing sludge according to claim 1, wherein a prada is used as a means for pressurizing the sludge. 3. The method according to claim 1, wherein the driving fluid filled in the ladder is discharged, and the sludge is sucked and stored in the pressurized container by utilizing a negative pressure generated by a reduction in the volume of the ladder. Item 4. The method for solubilizing sludge according to Item 2. 4. The method for solubilizing sludge according to claim 1, wherein the sludge is heated and heated before being stored in the pressurized container. 5. The method for solubilizing sludge according to claim 1, wherein the solubilization is performed by an impact force generated by colliding sludge ejected from a nozzle with a fixed object. . 6. The method for solubilizing sludge according to claim 1, wherein the solubilization is performed by an impact force generated by colliding sludge ejected from a plurality of nozzles. . 7. A pressurized container provided with a pladder for pressurizing the sludge therein, a nozzle connected to the pressurized container and jetting the pressurized sludge so as to cause a sudden pressure drop, A sludge solubilizer, comprising: a vacuum pump arranged to form a circuit for selectively performing pressure reduction and pressure reduction; and a driving fluid pump unit.