JP3732579B2 - Muddy substance dehydration method and apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to sludge such as sludge generated in civil engineering, construction work, sludge generated in sewage treatment plants, sludge accumulated in lakes, rivers, etc. The present invention relates to a method for dewatering a muddy substance that dehydrates a substance as much as possible, reduces the water content ratio of solids, and facilitates the treatment.
[0002]
[Prior art]
Conventional sludge dehydration methods include sun drying, heat dehydration using a hot air dryer, pressure dehydration using a filter press and belt press, vacuum dehydration using a rotary vacuum dehydrator, and centrifugation using a cyclone (centrifugal dehydrator). There are methods such as separation, vibration dehydration using a vibration sieve, solidification treatment by addition of cement, and addition of a chemical agent for separation using a flocculant.
[0003]
Of these, the sun-drying treatment method evaporates water over a wide area over a long period of time, but it is accompanied by a bad odor and is inefficient due to the weather. Even mechanical treatment methods such as heat dehydration and pressure dehydration are insufficient in dehydration, require a large processing space for installation of the apparatus, and have a high processing cost. Furthermore, the treatment with the additive / solidifying material has many problems such as deterioration of the chemical properties of the muddy substance. In addition, the water content ratio of the dehydrated solid is high, it cannot be used for landfilling and embankment, and there are many cases where it is necessary to treat industrial waste.
[0004]
[Problems to be solved by the invention]
In contrast to these methods, the treatment method by vacuum dehydration is relatively effective. For example, the outside of the rotating screen drum is brought into contact with the sludge in the dewatering tank and sucked by the vacuum pipe in the drum. What is discharged as a dehydrated cake has been used in sewage treatment plants for a long time, and dehydration may not be sufficient.
[0005]
As another processing method by vacuum dehydration, a method has been proposed in which the boiling point of sludge is lowered by vacuum and a heating medium such as steam is brought into contact with the periphery of the container to promote dehydration. However, the apparatus is still complicated. There are problems such as high processing costs.
[0006]
The object of the present invention is to eliminate the inconveniences of the conventional examples, and further reduce the processing cost by the processing method by vacuum dehydration, and reduce the water content ratio of the solid content after the processing. It can be realized, the apparatus is relatively simple, and the apparatus can be installed in a small site due to the downsizing of the apparatus, and further, the chemical properties are not deteriorated by the flocculant or the solidifying agent. The object is to provide a method and apparatus for dewatering a muddy substance.
[0007]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the present invention provides, as a method for dewatering a muddy substance, first, a steel outer cylinder provided with a lid on the top and formed with an intake drainage hole connected to a vacuum water suction device at the bottom; It consists of a metal net-like cage inner cylinder for introducing a muddy substance, which is arranged in an outer cylinder, in which a net bag is further laid and a filter cloth is laid therein, and a water collecting device is arranged in the inner cylinder Using a mud dewatering device, put the mud material so as to be wrapped with the filter cloth, intermittently vacuum suction through the intake drainage hole provided in the outer cylinder, and also placed in the mud material Promote dehydration from the inside of the muddy substance by the vacuum force of the water collecting device, secondly, form air holes in the lid and open these air holes intermittently, and third, air holes in the lid And the compressed air is intermittently blown into the outer cylinder through this.
[0008]
Fourthly, a steel outer cylinder provided with a lid on the top and an intake drainage hole connected to the vacuum water absorption device at the lower part, and a steel bag disposed inside the outer cylinder, A metal mesh cage inner cylinder with a filter cloth laid on the inside, and a mud substance is added to the inner cylinder by inserting a lower mud substance injection part and compressed air with a flexible barrier film. The gist is that the upper air layer section is compressed.
[0009]
As a mud dehydration device, firstly, a steel outer cylinder provided with a lid on the top and an intake drainage hole connected to the vacuum water absorption device at the lower part, and a steel outer cylinder disposed in the outer cylinder, A water collecting device that consists of a net bag and a metal net-shaped cage inner cylinder with a filter cloth laid in it, and promotes dehydration from the inside of the mud substance by vacuum force in the inner cylinder The second point is to form an air hole that is open to the outside in the lid, and third is to form an air hole that is connected to the compressor in the lid.
[0010]
Fourth, a steel outer cylinder provided with a lid on the top and an intake drainage hole connected to the vacuum water absorption device at the bottom, and a net bag disposed in the outer cylinder, and further filtered inside. It consists of a metal net-shaped cage inner cylinder with a cloth laid, and an upper part that pressurizes the muddy substance by inserting compressed air into the lower muddy substance input part with a flexible barrier film inside the inner cylinder The gist of the invention is that the air hole is partitioned into air layers and air holes are formed in the flexible barrier film.
[0011]
According to the first and sixth aspects of the present invention, a vacuum dehydration treatment method is performed by vacuum suction through an intake drainage hole provided in the outer cylinder. By adding a muddy substance so that a filter cloth is laid on the filter cloth and adding it to the filter cloth, a so-called hydrostatic dehydration process in which moisture content is discharged through the filter cloth is added. The water content of can be lowered.
[0012]
Further, in continuous operation, there is a possibility that the mesh of the inner cylinder and the filter cloth are clogged and moisture is not discharged, but such clogging can be prevented by intermittently performing vacuum suction.
[0013]
Furthermore, by arranging a water collecting device in the mud material and promoting dehydration from the inside of the mud material by vacuum force, consideration can be given to the mud material that tends to have an insufficient dehydration effect.
[0014]
In addition to the above action, the residual solids can be treated by lifting the net bag from the inner cylinder and carrying it as it is, which is very convenient, and the separation and collection of the residual solids can be performed in one stage.
[0015]
According to the second and sixth aspects of the present invention, in addition to the above action, the air suction is opened to introduce the outside air while the vacuum suction is intermittently performed. Atmospheric pressure is applied and clogging can be efficiently prevented.
[0016]
According to the present invention of claim 3 and claim 7, while the vacuum suction is intermittently performed, the pressure of the compressed air is applied to the filter cloth or the like from the outside by blowing the compressed air into the outer cylinder, It is possible to efficiently prevent clogging.
[0017]
According to the present invention of claim 4 and claim 8, the flexible barrier film partitions the lower mud substance input portion and the upper air layer portion, and the compressed air is put into the upper air layer portion to form the vacuum. In addition to the action of suction, dehydration can be further promoted by pressurizing the muddy substance.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 is an explanatory view showing a first embodiment of a method and apparatus for dewatering a mud substance of the present invention, FIG. 2 is a longitudinal side view of the main part of the same, FIG. 3 is a cross-sectional view taken along line AA 'of FIG. 4 is a cross-sectional view taken along the line BB 'of the above, and the apparatus of the present invention will be described first.
[0019]
In the figure, reference numeral 1 denotes a steel outer cylinder, which is formed with an intake drainage hole 2 at the bottom, and provided with a base 3 and a flange 4 for holding an inner cylinder 10 to be described later with a certain clearance. .
[0020]
Further, a lid 5 is provided on the open upper surface of the outer cylinder 1 so as to be closed in an airtight state by a fixing bolt 6. The lid 5 has a material introduction hole 7, an air hole 8, and a water collecting pipe hole 9 in the center. Formed.
[0021]
In the figure, reference numeral 10 denotes an inner cylinder installed in the outer cylinder 1, and as shown in FIG. 6, is composed of a metal net cage having a metal mesh plate 12 stretched on a frame 11 made of a horizontal member 11a and a vertical member 11b. In the figure, 13 is a ring-shaped hanger provided at the upper end of the inner cylinder 10.
[0022]
In the inner cylinder 10, a mesh bag 14 having a rough mesh, such as a knitted braid, was disposed, and a filter cloth 15 was further laid therein. The filter cloth 15 is preferably a polypropylene continuous fiber nonwoven fabric using polypropylene as a raw material. The filter cloth 15 may be formed in a bag.
[0023]
A mud substance supply pipe 16 is connected to the material introduction hole 7, and a compressor 18 is connected to the air hole 8 via an air intake valve 17 a using a three-way cock. Further, a vacuum water absorption device 19 is connected to the intake water drain hole 2 via a water absorption pipe 21 provided with an air intake valve 17b in the middle.
[0024]
A water collecting device 20 such as a well dropper is arranged in the center of the inner cylinder 10, and its water supply hose 20 a is connected to the inside of the lid of the water collecting pipe hole 9 provided in the lid 5. The water absorption pipe 21 from the vacuum water absorption device 19 is branched and connected to the end thereof. In the figure, reference numeral 22 denotes a switching valve provided in the branched water absorption pipe 21.
[0025]
The compressor 19 and the motor 19a of the vacuum water absorption device 19 and the air intake valves 17a and 17b are connected to the control device 23 for automatic operation control.
[0026]
Next, the method of the present invention using such an apparatus will be described. A predetermined amount of a muddy substance 24 is introduced from a mud storage tank (not shown) through a supply pipe 16 and a material introduction hole 7 so as to be wrapped with a filter cloth 15 in the inner cylinder 10. Close.
[0027]
In this state, a static pressure is applied to the mud material 24, and the moisture content is filtered by the filter cloth 15 and discharged from the mesh of the metal mesh plate 12 of the inner cylinder 10 to the outer cylinder 1. The device 19 is operated and the inside of the outer cylinder 1 is brought into a high vacuum state. As a result, the moisture in the muddy substance 24 is further forcibly sucked from the periphery and bottom of the inner cylinder 10 and guided into the tank in the vacuum water absorbing device 19 through the lower intake drainage hole 2.
[0028]
In addition, since it is considered that the water in the center of the mud material 24 is difficult to be sucked in such an operation, the water collecting device 20 that promotes dehydration from the inside of the mud material by vacuum force is placed in the mud material 24. The water in the muddy substance 24 is sucked from the water collecting device 20 to the vacuum water absorbing device 19. The waste water sucked into the vacuum water absorption device 19 is treated on the basis of discharge and discharged into sewage.
[0029]
The mesh of the filter cloth 15 and the mesh of the metal mesh plate 12 are likely to be clogged depending on the size of the mesh. As countermeasures, it may be possible to clean the mesh of the filter cloth 15 or the mesh of the metal mesh plate 12, but a cleaning device is required, which complicates the device. Therefore, in the present invention, the vacuum suction in the vacuum water absorption device 19 is intermittently performed, and during the pause operation, the air hole 8 is opened by the air intake valve 17a, and the air intake valve 17b is also opened to open the outer cylinder 1. By rapidly setting the inside to atmospheric pressure, the atmospheric pressure is applied from the outside of the inner cylinder 10 to push back minute portions clogged and prevent clogging.
[0030]
In another embodiment, the air hole 8 is connected to the compressor 18 without opening it, and compressed air is applied from the outside of the inner cylinder 10 by blowing compressed air from the compressor 18 into the outer cylinder 1. You may make it prevent clogging efficiently. The opening of the air hole 8 and the connection to the compressor 18 may be combined as appropriate.
[0031]
For the remaining solid content having a reduced water content by the vacuum dehydration method, the inner cylinder 10 is lifted and loaded into a transport device such as a transport vehicle or a belt conveyor, or the inner cylinder 10 is left behind. The net bag 14 is lifted together with the filter cloth 15 and discharged.
[0032]
In addition, as another method for discharging the remaining solid content, it is also possible to provide a hydraulic opening / closing device at the bottom of the inner cylinder 10 or the outer cylinder 1 and open and close it to take out.
[0033]
FIG. 5 shows a second embodiment of the present invention, in which the inner cylinder 10 is partitioned into a lower mud substance input portion 27 and an upper air layer portion 28 by a flexible barrier film 26 formed in a bellows shape.
[0034]
The material charging hole 7 provided in the lid 5 and the charging hole 29 provided at the upper end of the lower mud substance charging part 27 are communicated with each other by a flexible tube 30, and the lower mud substance in the flexible barrier film 26 is provided. An appropriate number of air holes 31 are formed in the flexible barrier film 26 so as to communicate the boundary between the inlet portion 27 and the upper air layer portion 28. Further, the net bag 14 is disposed in the lower mud substance charging unit 27 as in the first embodiment, and the filter cloth 15 is laid therein.
[0035]
Compressed air is introduced into the upper air layer portion 28 from the compressor 18 through the air holes 8, and the mud material 24 in the lower mud material charging portion 27 is pressurized so as to inflate this portion. At this time, the compressed air also flows from the air holes 31 to the lower mud substance input unit 27, passes through the mud substance 24, and fine air holes are generated inside, thereby promoting dehydration.
[0036]
As described above, in the second embodiment, dehydration is performed by applying pressure on the flexible barrier film 26 in addition to vacuum suction in the vacuum water absorption device 19.
[0037]
When the volume of the muddy substance 24 is remarkably reduced by this treatment, the muddy substance 24 is further supplied onto the dehydrated muddy substance 24 and the same dehydration is continued.
[0038]
【The invention's effect】
As described above, the method and apparatus for dewatering a muddy substance of the present invention can realize the following effects.
[0039]
First, the apparatus is relatively simple. By not using a chemical such as an aggregating agent, the initial cost and running cost can be reduced, and the processing cost can be reduced.
[0040]
Secondly, in the case of sludge generated by construction work or the like, the water content of the sludge after the treatment becomes low, becomes the same as ordinary soil, and can be used for embankment or the like.
[0041]
Thirdly, the equipment can be installed in a small site due to the downsizing of the equipment, and fourthly, no strong chemicals with a flocculant or a solidifying material, or neutralization of strongly alkaline mud substances is unnecessary, so that no chemicals are used. Is possible.
[0042]
Fourthly, when the solid content of the dehydrated mud substance is incinerated, since the water content ratio becomes smaller, less heating energy is required, so incineration energy is saved.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing a first embodiment of a method and apparatus for dewatering a mud substance of the present invention.
FIG. 2 is a longitudinal sectional side view of the main part showing a first embodiment of the method and apparatus for dewatering a mud substance of the present invention.
FIG. 3 is a cross-sectional view taken along line AA ′ of FIG.
4 is a cross-sectional view taken along line BB ′ of FIG.
FIG. 5 is a longitudinal sectional side view of a main part showing a second embodiment of the method and apparatus for dewatering a muddy substance of the present invention.
FIG. 6 is a perspective view showing an example of an inner cylinder.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Outer cylinder 2 ... Intake / drain hole 3 ... Base stand 4 ... Flange 5 ... Cover 6 ... Fixing bolt 7 ... Input hole 8 ... Air hole 9 ... Water collection pipe hole 10 ... Inner cylinder
11 ... Frame 11a ... Wheel
11b ... Vertical material 12 ... Metal mesh plate
13 ... Hanging tool 14 ... Mesh bag
15 ... filter cloth 16 ... supply pipe
17a, 17b ... Air intake valve 18 ... Compressor
19 ... Vacuum water absorption device 19a ... Motor
20 ... Water collector 20a ... Water hose
21 ... Water absorption pipe 22 ... Switching valve
23 ... Control device 24 ... Muddy substance
25… Valve 26… Flexible barrier
27… Lower mud substance input part 28… Upper air layer part
29 ... Input hole 30 ... Flexible tube
31 ... Air hole

Claims (8)

  A steel outer cylinder provided with a lid on the top and an intake drainage hole connected to the vacuum water absorption device at the lower part, and a net bag disposed inside the outer cylinder, and a filter cloth laid therein. It consists of a metal net-shaped cage inner cylinder for introducing the muddy substance, using a muddy substance dewatering device in which a water collecting device is arranged in the inner cylinder, throwing the muddy substance so as to be wrapped with the filter cloth, Mud is characterized in that vacuum suction is intermittently performed through an intake / drain hole provided in the outer cylinder, and dehydration is promoted from the inside of the mud by the vacuum force of the water collecting device arranged in the mud. Method of dehydration.   2. A method for dewatering a mud according to claim 1, wherein air holes are formed in the lid and the air holes are intermittently opened.   The method for dewatering a mud-like substance according to claim 1, wherein air holes are formed in the lid, and compressed air is blown intermittently into the outer cylinder through the holes.   A steel outer cylinder provided with a lid on the top and an intake drainage hole connected to the vacuum water absorption device at the lower part, and a net bag disposed inside the outer cylinder, and a filter cloth laid therein. It consists of a metal net-shaped cage inner cylinder for introducing the mud substance, and an upper air layer part that pressurizes the mud substance by putting compressed air into the lower mud substance input part with a flexible barrier film inside the inner cylinder, The sludge is dehydrated by using a sludge dewatering device in which air holes are formed in the flexible barrier membrane, and the sludge is poured so as to be wrapped with the filter cloth, and is intermittently inserted through the intake drain hole provided in the outer cylinder. A method for dehydrating a mud substance, characterized by vacuum suction and pressurizing the mud substance by introducing compressed air into the upper air layer part. A steel outer cylinder with a lid on the top and an intake drainage hole connected to the vacuum water absorption device at the bottom, and a net bag inside this outer cylinder, and a filter cloth in it. Mud substance dehydration characterized in that it consists of a metal net-shaped cage inner cylinder for loading mud substance, and a water collecting device that promotes dehydration from inside the mud substance by vacuum force is arranged in the inner cylinder. apparatus. The dewatering device for a muddy substance according to claim 5 , wherein air holes that are open to the outside air are formed in the lid.   The mud substance dehydrating apparatus according to claim 6, wherein an air hole connected to the compressor is formed in the lid.   A steel outer cylinder provided with a lid on the top and an intake drainage hole connected to the vacuum water absorption device at the lower part, and a net bag disposed inside the outer cylinder, and a filter cloth laid therein. It consists of a metal net-shaped cage inner cylinder for introducing the mud substance, and an upper air layer part that pressurizes the mud substance by putting compressed air into the lower mud substance input part with a flexible barrier film inside the inner cylinder, An apparatus for dewatering a mud-like substance, characterized in that the air holes are formed in the flexible barrier film.

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