JP2951499B2 - Two-stage slurry processing method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The disclosed technology relates to a system for effective solid-liquid separation of slurry and sludge discharged from factory waste liquid and construction waste material, and effective reuse of solid-liquid separated chocolate-like cake. Belongs to the technical field.

[0002]

2. Description of the Related Art As is well known, the recent prosperity of industry has greatly contributed to the improvement of citizens' lives and the development of culture, but recently, industrial development has caused a large-scale pollution problem, As environmental pollution has been brought about, the development of industry can no longer be ignored, and even if it cannot be continued without harmony with these, the pollution prevention industry and environmentally harmonious industry Etc. are even attracting attention as new industries.

[0003] In various chemical industries, pharmaceutical industries, food industries, chemical industries, agriculture and fisheries industries, construction industries, and the like, not only effective treatment of industrial waste liquids and industrial wastes, but also active In recent years, there has been a strong demand for effective reuse. In particular, the volume reduction of sludge generated from slurries of factory wastewater and construction wastewater, and the ease of incineration and burial, etc., have been simply depolarized. Technology that can be effectively reused as construction materials, deodorants, filtering agents, surfactants, etc. by adding and mixing flocculants, etc., which had been treated as a general waste treatment. Research has been improved.

[0004] In addition, sludge or the like from which the slurry is first solid-liquid separated is finally solid-liquid separated to reduce the volume to a chocolate-like cake, which is then incinerated, buried, and further solidified for effective reuse. A high-pressure filter press is widely used as a system that can achieve extremely high solid-liquid separation efficiency, and is being used effectively.

[0005]

However, such a high-pressure filter press having a very high solid-liquid separation efficiency is basically more effective than other various solid-liquid separation devices, but has a high water content of the supplied slurry. When the rate is high, in the solid-liquid separation process of the sludge, even if a so-called water passage is formed in the solid particle gap and dewatering is performed from a predetermined portion outside the water passage, the water passage, and However, since the moisture content in the vicinity thereof is high, there is a disadvantage that a chocolate-like cake cannot be obtained in the solid-liquid separation region between the filter frames,
In addition, since the cake has a large amount of water, the adhesion of the cake to the filter cloth is increased, and it is difficult to peel and remove the cake smoothly. As a result, the high-pressure filter press operates as designed. There was an inconvenience of being hindered.

[0006] Even if solid-liquid separation can be performed, it is difficult to obtain a recycled material from the cake obtained by the solid-liquid separation because of the high water content.

[0007]

SUMMARY OF THE INVENTION The object of the present invention is to solve the problems in the slurry processing centering on a high-pressure filter press used in a solid-liquid separation system for preventing pollution and harmonizing the environment with the industrial development based on the prior art. The technical problem to be performed, the primary dehydration to a semi-dehydrated state in advance for solid-liquid separation of slurry to sludge so that the function of the high pressure filter press can be fully exhibited,
The sludge dehydrated by the primary depressurization by high pressure is fed to a filter press to surely make it into a chocolate-like cake having a low water content by the secondary dehydration, and furthermore, it is possible to reuse the activated sludge waste material by the subsequent stage of dry distillation. It is an object of the present invention to provide an excellent two-stage slurry treatment method which is advantageous in the field of application of pollution prevention technology and environmentally friendly technology in various industries, and a slurry treatment apparatus directly used in the method.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the construction of the invention of this application, which has the above-mentioned object and the gist of the claims, has been made in order to solve the above-mentioned problems.
A slurry such as activated sludge is subjected to a predetermined coagulant addition and the like,
The water content is semi-dehydrated to about 40 to 60% for inorganic slurry and about 75 to 90% for organic slurry, and the mixture is kneaded by a mixer, and this is pressed into an elastic membrane of a high-pressure pumping device. The elastic membrane is repeatedly expanded and contracted by negative pressure, positive pressure, etc., and is formed in the sludge in the expansion and contraction process, and the water passage which is a hindrance condition in the solid-liquid separation by the next-stage filter press is formed. In order to prevent formation, deaeration and discharge, or intake and deaeration, remove sludge mist during this time, and perform explosive scavenging with high-pressure air,
The water content is reduced, and the mixture is pumped to a filter press at a high pressure of 30 kgf / cm2, or the slurry such as activated sludge is temporarily semi-dewatered to about 40 to 60% to be kneaded as described above, and then pumped to the filter press. To perform a solid-liquid separation action at high pressure to form a chocolate-like cake having a thickness of about 17 to 20 mm. The resulting chocolate-like cake is further supplied to an autoclave, heated in vacuum, and subjected to dry distillation to obtain an exhaust gas. Circulates, cools, dehydrates, deodorizes, burns with a burner, and finally effectively reuses as useful materials such as filter media, deodorizers, surfactants, fuel charcoal, or solidification materials for construction. It takes technical measures to make it possible.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

The illustrated embodiment is an embodiment of a sludge treatment system for effectively reusing a slurry discharged from construction sludge or the like into a filtering material or a deodorant as a useful material or a construction material. 1. It comprises a high-pressure solid-liquid separation plant 1 in the former stage shown in FIG. 1 and a dry distillation plant 2 shown in the latter stage in FIG. 2, both of which are installed adjacent to each other.

As shown in FIG. 1, the solid-liquid separation plant 1 has an oil suction / discharge port 4 for hydraulic fluid passing through a check valve 5 and a switching valve 6 on one side of a drum-shaped casing 3 of a pressure feeding device. The casing 3 is provided with a hydraulic pump 7 and is connected to an oil tank 8. A swelling-type mesh mesh support 9 is provided inside the casing 3, and a rubber-made expansion An extension type elastic film body 10 is provided so as to be able to expand and contract and is provided together with the base of the mesh body 9 together with the casing 3. The outer side of the elastic film body 10 is provided in a hydraulic fluid chamber 11 and an inner sludge chamber 12. An electromagnetic on-off valve 13 is provided above the base of the casing 3 in the sludge chamber 12.
And an external filter 16 is connected to a portion separated by a considerable distance via an opening / closing valve 15.

A ceramic filter 14 'having a fine void as an internal filter in the entire cross section of the exhaust chamber 14 is provided in the exhaust chamber 14 to remove air such as mixed pressure air from the slurry chamber 12 as described later. During the operation, sludge mist and the like are prevented from impairing the exhaust function by entering and accumulating in the exhaust chamber 14, and a high-pressure air outlet 14 '' is provided at one upper side of the ceramic filter 14 '.
Is opened and connected to a high-pressure compressed air source 14 ′ ″ via an electromagnetic on-off valve 13 ′.
In such a case, the high pressure air is explosively expelled from the air jet port 14 ″ in the case of
6 can be discharged.

A sludge supply port 17 is provided at the rear of the casing, and a screw type feeder / mixer 20 connected to a drive motor 19 via an electromagnetic opening / closing shutter 18 is connected.

Since the screw type feeder / mixer 20 has a screw fin, solid content and air bubbles are entirely generated during the advance of sludge after primary dehydration supplied from the hopper 21. It is kneaded sufficiently so as to be in a uniformly dispersed state, and each air bubble is easily exhausted to the exhaust chamber 14 in an airtight state in the elastic film body 10.

A slurry tank 24 and a flocculant tank 25 are connected to a feed hopper 21 of the screw type feeder / mixer 20 via a suitable centrifugal separator 22 known in the art.

In the slurry tank 24, a slurry having a high water content including waste mud from a construction site or the like is stored in a predetermined amount. In the flocculant tank 25, an appropriate slurry such as salt iron or quick lime is stored. Flocculant is stored.

The centrifugal separator 22 is provided with a well-known centrifugal dehydrator, and the slurry from the slurry tank 24 is supplied with the slurry mixed with the above-mentioned coagulant from the coagulant tank 25. Then, solid-liquid separation is performed, and sludge in a primary dewatering state is supplied to the supply hopper 21.

At the rear of the casing 3, a sludge discharge port 17 'is provided adjacent to the sludge supply port 17, and a pressure feed passage 27 is provided via an electromagnetic on-off valve 26.
Is connected to a filter press 28 as a solid-liquid separation device, and a cake discharge belt conveyor 29 below the filter press 28 is capable of supplying a chocolate-like cake 30 to an autoclave 31 of the carbonization plant 2 described in detail below. ing.

As shown in FIG. 2, in the dry distillation plant 2, a duct 33 is provided through an electromagnetic opening / closing valve 32.
Is connected to an exhaust pump 34 so that the inside of the autoclave 31 can be brought into a predetermined vacuum state.

Reference numeral 35 denotes a sealable lid that can be opened and closed inside the autoclave 31.
A circulation pipe 40 having an electromagnetic opening / closing valve 39 is provided via a durable flexible hose 38, and a predetermined cooling type dehumidifying device 41 and a deodorizing device 42 are provided. Interpolated,
The dry distillation gas from the sludge 30 in the autoclave 31 can be circulated and burned by a pump 43 in a burner 44 of the autoclave 31.

Reference numeral 45 denotes a water tank for recovering moisture in the dry distillation gas from the circulating cooling dehumidifier 41.

In the system plant having the above-described structure, slurry from a construction site containing a predetermined concentration of sludge is supplied from the slurry tank 24 to the centrifugal separator 22, and the coagulant tank 25 is supplied with salt iron, quicklime and the like. Is supplied, for example, at 5 to 10% by weight, and the centrifugal separator 2
2 through the centrifugal dewatering operation to perform primary dewatering as designed, and supply the sludge in a semi-dewatered state with a water content of 75 to 90% to the feed hopper 21 of the screw type feeder / mixer 20.

In this case, when the composition of the slurry is about 40% or less of the organic matter ratio, it is also possible to design a primary dewatering sludge having a water content of about 40 to 60%.

Then, the screw type feeder / mixer 20 is rotated by the motor 19, and the electromagnetic shutter 18 and the electromagnetic opening / closing valve 15 are opened while further kneading and stirring so that the sludge in a semi-dewatered state is uniformly dispersed. On the other hand, by closing the electromagnetic on-off valves 26 and 13, the sludge chamber 12 of the elastic film body 10 of the casing 3 is closed.
To supply pressure.

In this case, the sludge supplied from the slurry tank 24 through the centrifugal separator 22 and the respective mechanisms such as the supply hopper 21 is in a state in which fine sludge is inevitably contained therein. In the process of passing through the feeder / mixer 20 of the type, the foams are integrated into one another, enlarged in size, distributed uniformly and supplied as sludge inside the elastic membrane 10 of the casing 3.

In the process, the operating oil is returned to the oil tank 8 by the action of the switching valve 6 and the hydraulic pump 7 to the hydraulic fluid chamber 11 in the casing 3 or is sent under pressure, and the elastic membrane 10 is The sludge which is expanded and contracted in a push-pull manner and in which bubbles are uniformly dispersed in combination with the extrusion pressure of the screw type feeder / mixer 20 is supplied to the sludge chamber 12 in the elastic film body 10 in a full state.

When the elastic film body 10 comes into contact with the mesh body 9 of the support from the inside, the state is detected by an optical sensor (not shown), and the motor 19 and the hydraulic pump are also transmitted through a control device (not shown). 7 stops, the expanded state of the elastic film body 10 stops, and the elastic film body 10 is pressed against the inner surface of the support body 9 to prevent the appearance of the overtension state, thereby avoiding material fatigue.

Then, the electromagnetic opening / closing valve 13 'is closed by the program through the control device (not shown),
When the electromagnetic on-off valve 13 opens, the electromagnetic on-off valve 1
5 is closed, the oil pump 7 operates for a set minute time, and the pressure of the hydraulic fluid chamber 11 is increased by the supply of the hydraulic oil, and when the elastic film body 10 is slightly reduced, the internal sludge chamber 12 is pressurized. When the sludge in the sludge chamber 12 is pressed, the large-sized bubbles in a uniformly dispersed state are forcibly compressed and escape upward, and are confined in the exhaust chamber 14 under pressure.

In this process, the exhaust chamber 1
4 has a ceramic filter 14 'so that sludge mist can be prevented from entering the sludge chamber 14. Also, since the electromagnetic valve 13' is closed, high-pressure air is not blown into the exhaust chamber 14 but is discharged into the sludge. Is stored in the exhaust chamber 14.

In this case, the electromagnetic open / close valve 1
5 is closed, and the air of the bubbles in the sludge is stored in the exhaust chamber 14.

If microparticles such as sludge mist intrude and accumulate in the exhaust chamber 14 through the fine gaps of the ceramic filter 14 'with time, unexpectedly,
The electromagnetic open / close valve 13 ′ is opened in a predetermined manner via the control device, and high-pressure air from a high-pressure air source 14 ′ ″ is blown out from a high-pressure air discharge port 14 ″ into the exhaust chamber 14 ″, and the explosive energy is used. The accumulated sludge mist is scavenged and discharged to the external filter 16 via the opening / closing valve 15.

In this process, the voids in the ceramics 14 'of the internal filter are fine, so that the flow resistance is large, and the explosive air is not returned to the sludge chamber 12 and the sludge mist is not returned.

The external filter 16 easily filters and discharges the sludge mist at that time.

Therefore, the exhaust function of the exhaust chamber 14 is always maintained.

Then, after a set short time, the electromagnetic open / close valve 13 is closed via the control device, and the open / close shutter 18 is opened.
Puts the sludge chamber 12 under pressure and keeps it closed,
The backflow of the sludge to the screw type feeder / mixer 20 is prevented, and then the electromagnetic on-off valves 26 and 15 are opened via a control device according to a program, and the air in the exhaust chamber 14 is evacuated via the filter 16. , The sludge is opened and closed with no bubbles in the dispersed state,
The liquid is supplied to the filter press 28 via the pressure feed passage 27, receives a sufficient compressing action, and performs a predetermined solid-liquid separation as in the conventional mode.

In this case, the pressurization of the sludge by the contraction of the elastic film body 10 as the solid-liquid separation action is performed, for example, by:
40 kgf / cm2 is good (actually 39-38 kgf
/ Cm2 can produce the same effect. ), Thus
Secondary dehydration is performed in the filter press 28, and as a whole, two-stage dehydration is performed by the primary dehydration by the centrifugal separator 22 and the secondary dehydration of the filter press 28 with respect to the semi-dewatered sludge. Solid-liquid separation by near dehydration is performed, and solid-liquid separation by nearly complete dehydration is performed.

In the solid-liquid separation by the filter press 28, the sludge mist having a large size in the sludge chamber 12 in the elastic film body 10 of the pressure feeding device is discharged to the exhaust chamber 1.
4, the water supply passage for the air bubbles (Mizumichi) disappears from the sludge, the water content is reduced, solid-liquid separation is performed with high efficiency, and When the chocolate-like cake 30 is formed, the chocolate-like cake 30 does not adhere to the filter cloth due to the low moisture content at the time of opening the frame, sufficiently good releasability is obtained, and the chocolate-like cake 30 is unloaded from the unloading conveyor 29. Is performed very easily, and the smooth operation of the filter press 28 is performed.

[0038] This means that, as described above, since the water passage (Mizumichi) disappears, a chocolate-like cake having an extremely low water content can be obtained, and solid-liquid separation by a conventional one-stage filter press can be obtained. As a result, a chocolate-like cake 30 having a low water content is obtained.

In this case, the water content was 50 measured by experiment.
It was confirmed that the thickness of the chocolate-like cake 30 was as thick as 17 to 20 mm in the form of a block type.

In this way, even if the obtained chocolate-like cake 30 is incinerated and buried as it is, disposal is extremely easy because the volume reduction by dehydration is performed at a high level.

However, in the invention of this application, the chocolate-like cake 30 which has been solid-liquid separated by the filter press 28 is further subjected to dry distillation and effective reuse for various materials as shown in FIG. And carbonization plant 2
At this time, the lid 35 is opened via the joint 36 and the hook 37 (at this time, the gas exhaust circulation path 40 does not hinder the circulation function via the flexible hose 38), and the chocolate-like cake 30 is placed inside. The fixed amount is charged and filled, the lid is closed, the electromagnetic open / close valve 32 is opened via the operation of the exhaust pump 34, the inside of the autoclave 31 is evacuated to a predetermined low pressure via the duct 33, and the autoclave 31 is heated by the burner 44, The chocolate-like cake 30 is carbonized by low-pressure heating.

Then, the carbonized gas generated in the autoclave 31 circulates through the flexible hose 38 through the flexible passage 38 via the pump 43 due to the opening of the opening / closing valve 39, and is interposed in the path. The water (water vapor) contained in the dry distillation gas is cooled and aggregated by the cooling type dehumidifying / dehumidifying device 41, and the water (steam) contained in the dry distillation gas is cooled and aggregated to be forcibly eliminated by the water tank 45, and the organic odor contained in the dry distillation gas is deodorized. It is deodorized by the device 42, is forcibly circulated to the burner 44, and is provided for combustion as fuel.

Then, the solid content carbonized in the form of coke is appropriately taken out through the opening of the lid 35, and includes, for example, a filter material, a deodorant, a soil conditioner, various building materials, and solid fuel charcoal. It is effectively collected and used.

The above-mentioned integrated plant can be continuously operated in a flow system by a control device (not shown).

It should be noted that the embodiments of the invention of this application are not limited to the above-described embodiment. For example, as a hardware for a solid-liquid separation plant, a reduced mesh material or the like is also provided on the sludge chamber side of the elastic membrane. Various modes can be adopted such as providing a posture support so as to prevent crack generation or breakage through repetition of wrinkles generated by folding of the elastic film body.

The slurry and sludge to be applied are not only activated sludge but also construction sludge and factory waste liquid, as well as activated sludge of agricultural and marine products and food industry.
For example, the present invention can be applied to squeezed refuse and the like, regardless of the mixing ratio of organic substances and inorganic substances.

As a matter of course, the elastic film can be reversed in design from the above embodiment.

As the internal filter in the exhaust chamber, a charcoal filter or the like other than the ceramic filter is used.

[0049]

As described above, according to the invention of the present application, the solid-liquid separation efficiency of the slurry such as construction waste sludge having a high water content and the slurry containing activated sludge is extremely high. When using a good filter press, the slurry is subjected to primary dewatering to make the semi-dewatered sludge uniformly dispersed, then degassing the bubbles contained therein, and forming a low water content sludge, By performing the secondary dewatering by feeding the sludge to the filter press by a high-pressure pumping device having an elastic membrane, bubbles between solids disappear in the solid-liquid separation process of the secondary dewatering, so-called water By eliminating the water passage of Michi, solid-liquid separation of sludge with an extremely low water content ratio is performed in a two-stage system, a chocolate-like cake is obtained, and the volume can be reliably reduced in the subsequent stage of dry distillation, etc. Burning directly It can also be used for disposal and landfill disposal, and when performing further carbonization treatment, the carbonized gas generated from the carbonized gas is low in water vapor content, etc., resulting in the use of carbonized filter media, soil improvers, deodorizers, surfactants and fuel coal. The effective use of resources can be effectively performed, and the excellent effects of effective reuse of resources and prevention of pollution and environmental harmony can be achieved.

Therefore, in the solid-liquid separation, the primary dehydration is performed, and the semi-dewatered sludge by the primary dehydration is subjected to a two-stage type slurry treatment in which the secondary dehydration is performed through a filter press. As for the cost, as a result, there is an excellent effect that it works effectively in industrial policy.

Further, since it can be effectively reused as a filter material, a deodorant, a surfactant, a soil conditioner, a fuel coal, a construction material, etc., an excellent effect that resources can be activated and recycling can be achieved. Is done.

Further, the invention of this application has an advantage that it is extremely effective also as a system plant because the entire processing from slurry generation to dry distillation is carried out as a single plant.

The liquid contained in the sludge such as sludge mist is degassed out of the casing by high-pressure air, so that the solid-liquid separation with respect to the slurry in the temporary solid-liquid separation is efficiently performed. Is played.

[Brief description of the drawings]

FIG. 1 is a schematic structural diagram of a solid-liquid separation plant of the invention of this application.

FIG. 2 is a schematic structural diagram of a carbonization plant.

[Explanation of symbols]

Reference Signs List 3 casing 10 elastic film body 12 sludge chamber 28 solid-liquid separator (filter press) 14 exhaust chamber 20 sludge supply device 17 supply port 17 'discharge port 13, 14, 15 deaeration device 13, 15, 18, 26 opening / closing valve

Continued on the front page (51) Int.Cl. ⁶ Identification code FI C02F 11/10 C02F 11/10 Z

Claims (11)

(57) [Claims] A sludge obtained by primary dehydration of a slurry is supplied into a swellable elastic film provided in a casing, and the sludge is separated into solid and liquid at the next stage through expansion and contraction of the elastic film. In the two-stage slurry treatment method in which the slurry is pressure-fed to the device and subjected to secondary dewatering, and subjected to the next-stage treatment, after the sludge obtained by primary dewatering the slurry is kneaded in a uniformly dispersed state,
The gas contained in the sludge is supplied to the elastic membrane through a ceramic filter in a process of expanding and contracting the elastic membrane.
And, so as to <br/> degassed by scavenging high-pressure air of the high pressure air source outside the casing, two-stage slurry treatment method characterized by so as to remove sludge mist during dehydration gas. 2. A two-stage slurry processing method according to claim 1, wherein said sludge mist is discharged through scavenging by explosive gas. 3. The primary dewatering of the slurry is carried out at a water content of 75-9.
2. The two-stage slurry treatment method according to claim 1, wherein the semi-dehydrated state is set to 0%. 4. The primary dewatering of the sludge is carried out at a water content of 40-6.
2. The two-stage slurry treatment method according to claim 1, wherein the semi-dehydrated state is set to 0%. 5. A sludge obtained by primary dewatering of a slurry is supplied to a swellable elastic film inside a swelling type provided in a casing, and the sludge is separated into a next liquid and a solid through the expansion and contraction of the elastic film. In a two-stage slurry treatment method in which the sludge subjected to primary dehydration is kneaded and then fed into an elastic film body, and the sludge is subjected to a process of expanding and contracting the elastic film member in a two-stage slurry treatment method in which the sludge is subjected to secondary dehydration by feeding to an apparatus for secondary dehydration. Claims characterized in that the gas contained in the sludge is degassed by removing the sludge mist out of the casing, and the chocolate-like cake obtained by solid-liquid separation is subjected to dry distillation in an autoclave. 2. The two-stage slurry treatment method according to claim 1, wherein 6. A swelling-type elastic film body is provided in a drum type casing so that its base is fixed to the casing so as to be expandable and contractable, and a supply port connected to a sludge supply device is provided at the base of the casing. In a slurry processing apparatus provided with a discharge port connected to the solid-liquid separation apparatus, the sludge supply apparatus has a kneading apparatus, and a deaeration apparatus having an open / close valve is provided at a base of the casing. A two-stage slurry processing apparatus, which is provided. 7. The two-stage slurry processing apparatus according to claim 6, wherein an internal filter is attached to said deaerator through an opening / closing bubble . 8. A two-stage slurry processing apparatus according to claim 9, wherein said on-off valve is an electromagnetic on-off valve. 9. A two-stage slurry processing apparatus according to claim 6, wherein an autoclave is connected to said solid-liquid separation device. 10. A two-stage slurry processing apparatus according to claim 9, wherein a gas circulation device is attached to said autoclave. 11. A two-stage slurry processing apparatus according to claim 10, wherein a liquid removing device and a deodorizing device are additionally provided to said circulating device.