JP2004261775A - Apparatus and method for draining/cleaning slurry - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for draining/cleaning slurry in high efficiency. <P>SOLUTION: This method for draining/cleaning slurry by using a group of two or more slurry treatment parts each of which is fixed independently of one another at a fixed position and is provided with a filter and in each of which slurry can be housed comprises a step (a) to supply slurry to each of the slurry treatment parts, a draining step (b) to suck/filter the supplied slurry, a cleaning step (c) to clean the residue obtained at the step (b) by supplying a cleaning liquid to the residue and suck/filter the residue-mixed cleaning liquid through the filter. These steps are successively carried out synchronously in each of the slurry treatment parts. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus and a method for dewatering and cleaning a slurry, and more particularly to a technique for dewatering and cleaning a slurry to obtain a clean solid.
[0002]
[Prior art]
Generally, various devices such as a drum filter, a filter press, a decanter, and a centrifugal separator have been used for the operation of removing and washing the slurry.
For example, in the dewatering of zeolites produced from coal ash, while it is required to recover and utilize the alkaline solution and to perform a high degree of dewatering to reduce the load of washing, good solid-liquid separation is required. A high recovery rate is also required at the same time. Further, it is also required to efficiently remove and remove the residual alkaline solution in a short time while suppressing the amount of the cleaning liquid used.
It should be noted that, for such a dewatering / separating apparatus, no prior art to be particularly specified can be found other than the above-described apparatuses as well-known techniques.
[0003]
According to the above-mentioned conventional separation device, even if it has a high performance in terms of a dewatering rate, it is insufficient in a recovery rate or a processing efficiency.
[0004]
[Problems to be solved by the invention]
Therefore, an object of the present invention is to provide an apparatus and a method for dewatering and cleaning a slurry, which can realize high processing efficiency in dewatering and cleaning the slurry.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the present inventors have conducted research focusing on batching and continuously processing slurry processing units, and as a result, provided a plurality of slurry processing units having a filter function, The present inventors have found that the above-described problems can be solved by synchronously and sequentially performing the liquid removing and washing steps on each of the slurries contained in these slurry processing units, and completed the present invention.
That is, according to the present invention, the following means are provided.
[0006]
(1) A slurry dewatering and washing device,
A slurry processing unit group in which two or more slurry processing units are arranged independently of each other, each of which is capable of containing a slurry and having a filter, and
The following means arranged in connection with this slurry processing unit group:
Slurry dewatering means for suction-filtering the slurry contained in the slurry processing section through the filter,
Cleaning liquid supply means for supplying a cleaning liquid to the processing unit after the liquid removal, and
Washing mixture dewatering means for suction-filtering the washing mixture in the processing section through the filter,
An apparatus comprising:
(2) The apparatus according to (1), wherein the means group further includes a slurry supply means for supplying a slurry to the slurry processing section.
(3) a fixed-quantity supply unit having a valve mechanism for controlling the supply of the slurry and / or the cleaning liquid to each slurry processing unit in accordance with the height position of the surface of the content of each slurry processing unit; Or (2).
(4) The valve mechanism is provided corresponding to each of the slurry processing sections, and is a float capable of generating buoyancy for the contents of each of the slurry processing sections, and a slurry for cleaning and / or cleaning each of the slurry processing sections. The apparatus according to (3), further comprising: a valve that shuts off supply of the supply target to the slurry processing unit when the float reaches a predetermined height position due to the supply of the liquid.
(5) The fixed-quantity supply means is disposed along the slurry processing unit group, and is provided at a position where the slurry processing units are disposed with respect to a pipe for supplying a cleaning liquid and / or slurry to each of the slurry processing units. The device according to (3) or (4), which is provided correspondingly.
(6) The respective operations by the slurry dewatering means, the cleaning liquid supply means, and the cleaning mixture dewatering means are sequentially and synchronously performed on each of the slurry processing units at a fixed position. , (1) to (5).
(7) The apparatus according to (6), wherein after the operations performed by the respective units performed in synchronization with each other, the slurry processing unit group moves to a slurry discharging step.
(8) The apparatus according to any one of (1) to (7), further including a cleaning unit configured to supply a gas to the cleaning mixture in the slurry processing unit and perform stirring cleaning.
(9) The apparatus according to (8), wherein the gas supply by the stirring and washing means is performed through the filter.
(10) The apparatus according to any one of (1) to (9), which is an apparatus for removing and washing a zeolite-containing slurry.
(11) The apparatus according to (10), further comprising means for supplying a zeolite-type conversion liquid to the slurry processing unit.
(12) A method for removing and washing a slurry,
The following steps are performed for each slurry processing unit fixed at a fixed position in a slurry processing unit group including two or more slurry processing units each having a filter and being capable of storing a slurry, each of which is independent of each other;
(A) supplying a slurry to a slurry processing unit;
(B) a slurry dewatering step of suction-filtering the slurry through the filter;
(C) a washing step of supplying a washing liquid to the residue after dewatering to wash the residue, and suction-filtering the washing mixture through the filter;
Are performed sequentially and synchronously.
(13) The method according to (12), wherein, in the cleaning step, after supplying a cleaning liquid, a gas is supplied to the slurry processing unit through the filter, and the cleaning mixture containing the residue is cleaned by gas stirring.
[0007]
According to these means, the slurry is divided into a plurality of processing units, and the dewatering / washing steps are performed synchronously and sequentially on each processing unit, thereby improving the processing efficiency. In addition, by adjusting the conditions of the dewatering and washing steps for the slurry processing section, a high processing efficiency can be easily obtained in addition to the required dehydration rate and recovery rate. Further, not only a high dehydration rate and a high recovery rate can be obtained, but also the change in the slurry characteristics is the same for each of the divided slurries (processing units), so that it is easy to adjust the washing time, the dehydration time, and the like. As a result, a wide range of responses is possible according to changes in the characteristics of the slurry and the residue.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
The slurry dewatering / cleaning method of the present invention includes the following steps for each of the slurry processing units of a slurry processing unit group including two or more slurry processing units each of which is provided with a filter and capable of storing a slurry independently of each other. The operation is performed synchronously, and the steps (a) to (c) are sequentially performed.
(A) supplying a slurry to a slurry processing unit;
(B) a dewatering step of suction-filtering the slurry through the filter;
(C) a washing step of supplying a washing liquid to the residue after draining to wash the residue and suction-filtering the washing mixture through the filter;
[0009]
Further, the slurry dewatering apparatus of the present invention is a preferred apparatus for performing the above method,
A slurry processing unit group in which two or more slurry processing units are arranged independently of each other, each of which is capable of containing a slurry and having a filter, and
The following means arranged in connection with this slurry processing unit group:
The slurry contained in the slurry processing unit, a slurry dewatering unit that suction-filters the slurry in the processing unit through the filter,
Supply means for supplying a cleaning liquid to the processing unit after the liquid removal, and
A washing and dewatering means for suction-filtering the washing mixture in the processing section through the filter is provided.
[0010]
In these inventions, the purpose is to separate the slurry into solid and liquid, and both the solid and the liquid in the slurry can be collected. In addition, various slurries can be targeted. For example, slurries containing various zeolites, pigments, dyes, gypsum, aluminum hydroxide, graphite, titanium compounds and the like as solid components, okara, red bean paste, potatoes, food-based slurries containing pet food materials, paper pulp , Pulp-based slurries such as fibers and pulp slurries, and various sludge slurries such as sewage sludge, general sludge and construction sludge. The method and apparatus of the present invention are particularly preferably applied to solid-liquid separation of a zeolite-containing alkali slurry obtained in a coal ash zeolite production step. Since the zeolite particles are fine particles and have a true specific gravity of 2, which is twice as much as water, but is porous, the particles contain a large amount of water. Therefore, the difference in specific gravity with water is small, and it is generally difficult to dehydrate by centrifugation. This is because dehydration and solid-liquid separation at a high recovery rate are required.
[0011]
As illustrated in FIG. 1, the dewatering and cleaning step of the present invention is applied to each of the slurry processing units in the slurry processing unit group including two or more slurry processing units each having a filter and capable of storing a slurry. Implemented for That is, in the present invention, the slurry is stored in two or more slurry processing units, and is divided into two or more processing units, and each process is performed synchronously for each of the divided processing units. After the washing step, it is preferable that the subsequent steps such as a step of discharging solids in the slurry processing section and a step of washing the slurry processing section are also performed synchronously.
Hereinafter, an embodiment of the slurry dewatering / cleaning method and apparatus of the present invention is illustrated in FIGS. 1 to 9 and described with reference to the embodiment. Note that the embodiments shown in these drawings are preferred embodiments of the present invention, but are not intended to limit the present invention.
[0012]
(Slurry processing group)
FIG. 2 shows a preferred embodiment of the device of the present invention. In the embodiment shown in this figure, a plurality of slurry processing units 4 are movably mounted on a chain conveyor 200 to form a slurry processing unit group 2 having an endless array.
Each of the slurry processing units 4 can store a slurry. The shape of the container for containing the slurry is not particularly limited. The shape may be a flat plate or a dish shape as long as the slurry can be accommodated, or a bread shape having a predetermined depth as needed. Further, a cover may be provided.
[0013]
As shown in FIGS. 3 and 4, the slurry processing section 4 is configured to be able to suck its contents and to supply gas and the like to the inside. Specifically, a filter 6 is provided in a part of the slurry processing section 4. The filter 6 is preferably provided on at least a part of the bottom of the slurry processing section 4, and is more preferably provided on almost the entire bottom. By providing the filter 6 in the slurry processing section 4, the suction filtration of the slurry can be performed in the slurry processing section 4, and the dewatering and washing step can be continuously performed.
As the filter 6, various filter materials having pores through which liquid in the slurry can pass and solid components do not pass can be used. Specifically, a filter cloth which is a mesh-like body made of woven or knitted fabrics of various fibers, a screen made of metal or resin, a mesh plate body such as a porous body, a porous body such as a porous ceramic, beads And the like. As the filter cloth, a filter cloth having an appropriate pore size (mesh size) is used in consideration of the particle size of the solid portion, the suction pressure, and the like. The material of the filter cloth is not particularly limited.
[0014]
These can be used alone or in combination of two or more, but it is preferable to use at least a filter cloth, and more preferably to use a filter cloth in combination with a mesh plate body. In this case, uniform suction from the filter surface during suction can be ensured by using the mesh plate body. This is because a gap through which the sucked liquid can move is secured by the interposition of the mesh plate body. The mesh plate also functions as a support for the filter cloth.
In particular, it is preferable that the filter material (particularly, the filter cloth) is provided so as to be exchangeable. For example, the filter cloth can be mounted on a mesh plate or a porous body or the like, and can be used in combination with another filter material and can be detachably provided from the filter material. When the filter material is replaceable, the yield is high and the discharge of the filtrate can be facilitated according to the characteristics of the slurry.
In the embodiment shown in FIGS. 3 and 4, a filter 6 including both a filter cloth 6a and a mesh plate 6b is provided.
As shown in FIGS. 3 and 4, the bottom of the slurry processing section 4 is provided with a hole for enabling liquid removal and gas supply, and for reliably supporting the contents during liquid removal and washing. It is preferred to have a bottom plate 10 with 8.
[0015]
In the group 2 of slurry processing units, the respective slurry processing units 4 are independent of each other. Here, being independent of each other means that the slurry can be individually accommodated and that suction filtration can be individually performed. Therefore, the slurry processing unit group 2 may be formed by any form of the slurry processing unit 4 as long as they are independent from each other in this sense.
It is preferable that the slurry processing units 4 are arranged in the slurry processing unit group 2 from the viewpoint of efficient execution of each step. As an arrangement form, it is preferable that at least two or more slurry processing units 4 are arranged continuously in one direction.
[0016]
Therefore, for example, as a form of being connected and arranged, the whole of the partition body formed so as to be able to individually store the slurry and divided into two or more along one direction and provided with a filter at the bottom of each partition part. Can be used as the slurry processing unit group 2. In this case, each partition corresponds to the slurry processing unit 4. Further, as another example, a plurality of bread-like bodies having the filter 6 at the bottom can be connected in tandem. Further, as shown in FIG. 2, there may be mentioned a slurry processing section group 2 in which the bread-like bodies are arranged on a conveying means such as a rail or a conveyor.
Preferably, as shown in FIG. 2, the plurality of slurry processing units 4 are arranged in an endless shape. According to this arrangement, a series of steps of supplying, draining, washing, and discharging the slurry and washing the slurry processing section can be easily performed synchronously, and can be repeatedly performed efficiently. .
[0017]
The steps (a) to (c) are synchronously and sequentially performed on the slurry in each of the slurry processing units 4 of the slurry processing unit group 2 configured as described above. That is, the step (a) is performed synchronously with respect to each of the slurry processing units 4 of the slurry processing unit group 2, and then the step (b) is synchronously performed with respect to the slurry processing unit group. Step (c) is performed synchronously (see FIG. 1).
According to the embodiment, the respective components are performed in units of the slurry accommodated in the slurry processing unit 4, so that the scattering and outflow of the slurry component to the surroundings are prevented. Further, in the present invention, since all the steps are completed in the slurry processing section 4, there is no movement of the slurry or solid content itself between the processing steps. Therefore, the loss of the solid component is small, and it is easy to secure a high recovery rate. Further, the process conditions can be set according to the characteristics of the slurry, such as the concentration and supply amount of the slurry, the amount of the cleaning liquid, and the cleaning method. Furthermore, since the slurry is processed in divided units, solid-liquid separation with a uniform recovery rate and dehydration rate can be achieved.
[0018]
In the method of the present invention, the dewatering / washing steps can be performed in units of the slurry processing unit 4; therefore, these steps can be performed synchronously and in parallel for each processing unit. As a result, the processing time from the supply of the slurry to the discharge of the solid content can be shortened.
In order to perform these steps synchronously and sequentially, it is preferable that the slurry processing unit 4 is fixed at a fixed position and the steps (a) to (c) are performed at the fixed position. According to this embodiment, synchronous, continuous, and simultaneous parallel steps can be easily implemented. In addition, the operation can be efficiently performed without loss of the moving time of the slurry processing section or the movement of the contents. In addition, by sequentially moving the slurry processing unit group 2 to an area where the steps (a) to (c) can be performed, these steps can be performed synchronously and sequentially.
After the cleaning step, a solid content discharging step and a slurry processing section cleaning step can be performed. It is not always necessary to perform the discharge step and the processing section cleaning step synchronously and sequentially with respect to the slurry processing section group 2. For example, as shown in FIG. 1, the processing unit 4 may be provided so as to sequentially execute a discharge step and a cleaning step. FIG. 1 means that these processes are individually and sequentially performed on each processing unit 4 without performing a discharge process and a cleaning process on each processing unit 4 synchronously. I have.
[0019]
Next, each means provided in the apparatus of the present invention will be described.
(Slurry dewatering and cleaning equipment)
As shown in FIG. 2, the slurry dewatering and cleaning (processing) apparatus 1 of the present invention has already been described as including the above-mentioned slurry processing section group 2, but has a means group 12 in addition to this. I have.
The means group 12 includes at least a slurry supply means 14 for supplying the slurry to the slurry processing section and a liquid removing means for suction-filtering the contents in the slurry processing section 4 through the filter. And a means for supplying a cleaning liquid to the residue in the processing section after the liquid removal. Further, the present apparatus 1 can be provided with a cleaning means 64 for supplying a gas from below the residue of the slurry processing section after supplying the cleaning liquid and stirring and cleaning the residue and the cleaning liquid.
[0020]
(Slurry supply means)
The slurry supply means 14 is not particularly limited as long as it can supply the slurry into the processing section 4. In the present invention, the slurry supply means 14 can supply the slurry to the plurality of processing sections 4 in a synchronous and equal amount. Is preferred. Various forms can be adopted for the synchronous and equal supply, but in the present invention, as shown in FIGS. 2 and 5, the supply amount at the liquid level of the slurry in the slurry processing section 4 is controlled. It is preferable to provide a fixed amount supply means 16 having a valve mechanism for adjusting. Further, it is preferable that a slurry storage unit 18 is appropriately provided.
[0021]
FIG. 5 to FIG. 7 show an example of such a quantitative supply unit 16. The quantitative supply means 16 is provided, for example, at a portion corresponding to each slurry processing unit 4 in a single slurry supply pipe 20 provided for the plurality of processing units 4.
It is preferable that the fixed amount supply means 16 is configured to be vertically movable. For example, the slurry supply pipe 20 is supported on the gantry 100 via an up-down mechanism 110 that can move up and down while maintaining the horizontal state. More specifically, the slurry supply pipe 20 is fixed to a support frame 120 connected to the vertical mechanism 110.
[0022]
The quantitative supply means 16 includes a supply pipe 22 for each slurry processing section 4, a float 24 which can float in accordance with the liquid level of the contents of the processing section 4, and the float 24 which corresponds to the vertical movement of the float 24. And a valve body 28 connected to a predetermined portion of the supply pipe so as to be openable and closable. The fixed amount supply means 16 closes the valve body 28 by the buoyancy that the float 24 receives when the liquid level of the contents in the processing section 4 reaches a predetermined level, and opens the valve body 28 when the float 24 does not receive the buoyancy. Is configured.
[0023]
The valve element 28 of the fixed quantity supply means 16 shuts off the supply line at a position where the supply pipe 22 is located, and when the valve moves above the cutoff position, the supply line can be opened.
The float 24 is provided on the liquid discharge side of the valve body 28 by being connected by a buoyancy transmission mechanism 30 such as a crank mechanism or a cylinder mechanism.
The buoyancy transmission mechanism 30 is configured such that when the float 24 moves upward due to buoyancy or the like, the valve body 28 moves downward to shut off the supply line, and when the float 24 moves free or moves downward, the valve body 28 moves upward to open the supply line. Is configured. The transmission mechanism 30 is preferably directly connected to the supply pipe 22 via the support 35.
[0024]
In the transmission mechanism 30, various configurations capable of forming the movement mode between the float 24 and the valve body 28 described above can be adopted. For example, as shown in FIG. The first arm 31, the second arm 32, and the third arm 33 connected to the float 24 are fixed to the support 35 at the intersection of the third arm 33, so that the float can move upward and the valve can move. It is possible to configure a crank mechanism capable of interlocking with the blocking of the body.
Such a slurry supply unit 14 can be used in common with a cleaning liquid supply unit 44 to be described later, including the quantitative supply unit 16.
In addition, if the initial setting position is determined in consideration of the specific gravity of the supplied material, it is possible to supply an arbitrary amount.
[0025]
Further, when the present apparatus 1 is used for dewatering and washing the zeolite slurry, the slurry supply means 14 can be used, for example, as a supply means for a zeolite type conversion liquid. The zeolite type conversion can be performed subsequently in the slurry processing section 4 after the slurry dewatering step. Further, in this case, by using a gas supply means described later, the type conversion liquid and the solid can be mixed and stirred to perform the type conversion effectively.
[0026]
(Slurry draining means)
The slurry draining unit 34 is a suction unit that can suck the inside of the processing unit 4 through the filter of the slurry processing unit. Conventionally known various suction means can be used as the suction means. For example, it can be a suction unit connected to a vacuum suction source. It is preferable to provide a filtrate (washing waste liquid) storage section 36 in the middle of the filtrate suction path.
As shown in FIG. 8, as a part of the liquid removing means 34 or a part of the slurry processing unit 4, a vacuum suctionable closed state can be formed on the lower surface side of the filter 6 of the slurry processing unit 4, and it can be detached. It is preferable to provide a suction chamber 38 provided at the bottom.
[0027]
The chamber 38 has a box shape having an opening substantially corresponding to the bottom of the processing unit 4, and partially has a hole communicating with a vacuum suction source.
In order to prevent external air from flowing into the chamber 38 during liquid removal (at the time of suction), the chamber 38 is closed between the chamber 38 and the processing section 4 so as to seal the chamber and the bottom of the slurry processing section. It is preferable to provide a sealing means 40 between the upper surface of the processing unit 4 and the bottom of the processing unit 4.
As shown in FIGS. 8 and 9, for example, the sealing means 40 includes a sealing member 42 made of an elastic material, a rail-shaped fixing member 43a, and a fixing member 43b that can be accommodated between the rails. can do.
The sealant 42 has a channel shape in cross section that opens upward, and has a shape that roughly corresponds to the periphery of the bottom of the processing unit 4.
The rail-shaped fixing member 43a is formed such that two rows of rails follow the bottom periphery of the processing section 4, and is formed so that the bottom of the sealing material 42 can be stored between the rails. Further, the fixing member 43b can be placed on the bottom of the sealing material 42 housed between the rails of the rail-shaped fixing member 43a.
By providing the sealing means 40 having such a configuration, it is possible to prevent air from flowing in from the opposing portion between the processing section 4 and the chamber 38 during liquid removal. Further, as described later, when the gas is supplied, it is possible to prevent the supplied gas from leaking to the outside.
[0028]
The dewatering means 34 is a slurry dewatering means if the content is a slurry in order to suction-filter the content in the slurry processing section 4. Of the cleaning mixture) can be used as a means for removing the cleaning mixture. That is, the present apparatus 1 can be provided with two kinds of liquid removing means so as to realize these two kinds of functions respectively, or can be provided with liquid removing means so as to share the two kinds of functions. .
[0029]
(Cleaning liquid supply means)
The cleaning liquid supply unit 44 is not particularly limited, and may be any liquid supply unit that can supply a predetermined amount of the cleaning liquid. It is preferable that the supply unit 44 can supply the same amount of the cleaning liquid to the plurality of slurry processing units 4 synchronously and synchronously. For this reason, it is preferable to employ a supply mechanism similar to that of the above-described slurry supply means 14, and more preferably, it is preferable to share the slurry supply means 14 and the cleaning liquid supply means 44. At this time, it is preferable that the fixed amount supply means 16 has the same configuration or is also used as a slurry supply means. A cleaning liquid reservoir 48 may be provided. In the embodiment shown in FIG. 2, the slurry supply means 14 and the cleaning liquid supply means 44 are also used. When the slurry supply means 14 is also used as the cleaning liquid supply means 44, the slurry supply and the supply of the cleaning liquid can be easily realized by switching the valve.
[0030]
(Cleaning means)
The present apparatus 1 can include a cleaning unit 64 as one of the unit groups 12. The cleaning means 64 is not particularly limited as long as gas can be supplied from the lower portion of the residue of the slurry processing section 4 after supplying the cleaning liquid and the residue and the cleaning liquid can be stirred and cleaned. Preferably, gas can be supplied to the inside of the processing unit 4 via the filter 6 of the slurry processing unit 4. The gas used in the cleaning means 64 is preferably air or water vapor. As the air, a compressed air source may be used.
When the gas is supplied from the lower part of the residue, that is, from the bottom of the processing unit 4, the residue (cake) compressed by the dewatering is loosened, whereby the cleaning liquid and the residue are well stirred, and the cleaning effect is obtained. Can be secured and improved. In addition, the air permeability of the cake is improved, the suction time in the subsequent stage is shortened, and the processing capacity is improved. Further, when supplied via the filter 6, clogging of the filter 6 is also eliminated.
[0031]
In supplying the gas, it is preferable to provide a gas supply chamber on the lower surface side of the filter 6 of the processing unit 4. This chamber can have the same configuration as the suction chamber of the liquid removing means, and can be shared with the chamber. The sealing means 40 already described functions effectively when supplying gas.
[0032]
(Washing mixture dewatering means)
The cleaning mixture draining unit 54 is a unit for draining the cleaning mixture after the supply of the cleaning liquid in the slurry processing unit 4.
The washing mixture removing means 54 is not particularly limited, and may be any means capable of removing the washing mixture. Preferably, the liquid removing means 54 is only required to be able to synchronously suction the inside of the plurality of slurry processing sections 4, and is not particularly limited, but a liquid removing mechanism similar to the above-described slurry liquid removing means 34 is provided. It is preferable to employ it, and it is more preferable to share it with the slurry draining means 34. At this time, it is preferable that the chamber 38 is also shared.
[0033]
Further, the present apparatus 1 can be provided with a unit 70 for discharging solids from the slurry processing unit 4 after cleaning, and a unit 80 for cleaning the inside of the slurry processing unit after discharging solids. These means may be provided as a part of a group of means. The form of the discharging means 70 and the cleaning means 80 is not particularly limited, but the discharging means and the cleaning step may be provided so as to perform the discharging step and the cleaning step synchronously for each of the arranged slurry processing sections 4. It is preferable to provide such that the discharging step and the cleaning step are performed sequentially.
[0034]
The above-mentioned means group 12 is preferably arranged so that the respective steps can be sequentially and synchronously performed on the slurry processing section 4 at a fixed position in the order of the liquid removing step and the cleaning step. That is, these units are arranged so as to be able to be performed synchronously for each of the plurality of slurry processing units 4. When the slurry supply means 14 and the cleaning liquid supply means 44 are shared, and the slurry dewatering means 34 shares the slurry dewatering and the cleaning mixture dewatering means 54, the processing units are compact. Each step can be performed within a proper range. Further, even if a plurality of such slurry processing units 4 are arranged in parallel to form a slurry processing unit group, the overall device area can be made compact.
[0035]
Further, it is preferable that after the step by these means group 12 is completed, the slurry processing section group 2 is moved from a fixed position and can be moved to a cake discharging step and a processing section cleaning step. More preferably, the slurry processing unit 4 is arranged in an endless shape, circulated after the solid content (cake) discharge and the cleaning of the processing unit have been completed, and circulated to be relocated to a process execution area for washing and removing the slurry. The configuration is as follows.
[0036]
In order to realize such a movement of the slurry processing unit 4, the processing unit group 2 is supported by a conveying means such as a rail or a conveyor, or one end of a large number of the processing units is supported on a rotating shaft. It is preferable to move using a transporting means that is provided with a processing unit or means and rotates. This is because it is easy to synchronize the fixed position with respect to the conveying means and the cycle time of each process. Such a process can be performed at low cost by arranging the slurry processing unit group 2 in a movable endless manner.
[0037]
In the embodiment shown in FIG. 2, the chain conveyor 200 transports the filter 6 of the slurry processing unit 4 in one direction while holding the filter 6 in a horizontal state, and inverts the slurry processing unit 4 at the conveyor end 200a. The slurry processing unit 4 is supported in a horizontal state at the other end 200b.
Hereinafter, the details of each step of the method of the present invention will be described with reference to this apparatus mode.
[0038]
(Slurry supply process)
First, the slurry is supplied to the slurry processing unit 4. The slurry processing section 4 is transported by the chain conveyor 200. It is preferable that the process operation area to be conveyed is a fixed position. The inside of the slurry processing section 4 transported to the process execution area has already been cleaned.
[0039]
In the present embodiment, the slurry supply means 14 is configured to be supplied from the slurry supply tank 18 to each of the slurry processing units 4 via the respective quantitative supply means 16 by a pump. First, the fixed amount supply unit 16 is moved down by the up-down mechanism 110 and set so that the free float 24 comes to a predetermined height position of the slurry processing unit 4.
When the float 24 of the fixed quantity supply means 16 is in a free state, the valve element 28 is located above the shut-off position and the supply line is open, and liquid supply is started via the supply pipes 20 and 22, and the processing section is started. When the amount of slurry in 4 reaches a predetermined level, float 24 rises by buoyancy, valve body 28 moves down and reaches the shutoff position, the supply line of supply pipe 22 is cut off, and supply pipe 22 is cut off. The supply of the slurry to the processing unit 4 via the processing unit is stopped. Once the valve body 28 reaches the shut-off position and closes the supply line, the supply line is not opened because it receives the hydraulic pressure of the slurry from above.
[0040]
According to the quantitative supply mechanism using the float 24, the supply amount can be easily and reliably controlled without using flow rate control or electrical liquid level control. That is, in supplying a constant amount to a plurality of arranged processing units 4 in a synchronous manner, conventionally, the time required for slurry supply to each processing unit due to a pressure difference generated due to a difference in the mutual positions of the metering valves has been known. Although it was difficult to control the amount of slurry supplied to each processing unit because it was different, according to this quantitative supply means 16, even if the supply time difference occurred due to the pressure difference, each slurry was kept constant. Amount can be supplied.
The amount of slurry for one unit is determined in consideration of the type of slurry, the dehydration rate to be obtained, and the processing capacity. Although it depends on the powder characteristics of the solid content in the slurry, the slurry amount is preferably such that the solid content remains at a height of about 10 mm to about 40 mm after dewatering. If it is less than 10 mm, the efficiency is poor, and if it exceeds 40 mm, the pressure loss becomes too large and a suction time is required.
The zeolite-containing alkali slurry obtained in the step of producing zeolite from coal ash has a solid content of approximately 10 to 30 wt%, and the present apparatus and method can be preferably applied to a zeolite-containing slurry having the solid content.
When the valve bodies of all the supply pipes 22 move down and the respective supply lines are cut off, the supply of the slurry to the supply pipes 20 is stopped. Next, the quantitative supply means 16 is moved upward.
[0041]
(Slurry draining process)
In the dewatering step, the liquid is suction-filtered from the slurry. A liquid removing means 34 is disposed in the process execution area. In the present embodiment, the liquid removing means 34 is provided at a position corresponding to the fixed position of the slurry processing section 4 by the chain conveyor 200. In the present embodiment, the liquid removing means includes a chamber 38 connected to a vacuum suction source and a filtrate reservoir 36 provided in the middle of the suction path.
When the chamber 38 is in close contact with the lower surface of the slurry processing unit 4 and the vacuum suction source is operated, the liquid in the slurry flows down into the chamber 38 via the filter 6 such as a filter cloth and the suction holes 8. The filtrate further moves from a discharge port provided in the vicinity of the bottom in the chamber 38 to the storage unit 36, where it is stored.
[0042]
As described in the slurry supply step, this step is preferably performed such that the solid content thickness after dewatering is about 10 mm to about 40 mm. The suction pressure is preferably 0.02 to 0.06 MPa. This is because if each is below the lower limit, the efficiency is low and the dehydration rate is also lowered. If the upper limit is exceeded, the suction time is lengthened or a large suction device is required.
After performing suction for a predetermined time with a predetermined suction force, the valve is operated to release the airtightness of the sealing means 40.
[0043]
(Slurry washing process)
The slurry processing section 4 that has completed the liquid removing step moves to the cleaning step at that position. In the cleaning step, the cleaning liquid is supplied and the cleaning mixture is drained. Preferably, a gas is supplied to the cleaning mixture for agitating cleaning.
The supply of the cleaning liquid of the present embodiment shares the use of the slurry supply means, and the removal of the liquid uses the above-described liquid removal means provided with the suction chamber 38 having the same configuration as the slurry removal liquid means 34. The stirring cleaning uses a group of pipes connected to a compressed air source so as to share the suction chamber and supply air to the chamber.
[0044]
The cleaning liquid may be, for example, water or the like. In this embodiment, the cleaning liquid is supplied from the cleaning liquid storage unit 48 to the slurry processing unit 4 via the slurry supply unit 14.
Prior to the supply of the cleaning liquid, the float 24 of the quantitative supply unit 16 is adjusted to be located at a predetermined height in the processing unit 4. After adjusting the quantitative supply means 16, a predetermined amount of the cleaning liquid is supplied to each processing unit 4. As a result, a cleaning mixture of the slurry solids and the cleaning liquid is formed in the slurry processing section 4.
[0045]
Although the washing mixture can be directly drained, washing by the washing means 64 can also be performed. When performing such a cleaning step, a gas is supplied from below the cleaning mixture using the cleaning means 64. Specifically, gas is supplied into the processing unit 4 through a filter at the bottom of the processing unit 4. By supplying the gas, the solidified residue in the processing section 4, particularly in the vicinity of the bottom thereof, is loosened and mixed with the cleaning liquid to improve the cleaning effect. Corrects the unevenness of the surface of the residual solids formed by the drop impact of the cleaning liquid when supplying the cleaning liquid, improves the permeability of the residue and makes the suction effect uniform, thereby shortening the suction dehydration time. be able to. Further, by causing gas to flow in the opposite direction to that at the time of liquid removal, clogging of the filter can be eliminated, and the amount of residue adhering to the filter at the time of cake discharge can be reduced. The pressure of the supplied gas is preferably 0.05 MPa or more and 0.15 MPa or less. When the pressure is less than 0.05 MPa, the stirring is weak, and when the pressure exceeds 0.15 MPa, excess air causes overflow or air loss.
[0046]
After supplying the cleaning liquid or after stirring and cleaning, the cleaning mixture is drained. Dewatering can be performed in the same manner as in the dewatering step.
In the cleaning step, the cleaning liquid and / or the cleaning waste liquid generated in the subsequent cleaning step is supplied to the residue of the slurry processing section 4, and then the solid content can be cleaned by suction filtration. The suction and the movement of the filtrate are the same as in the liquid removing step. Furthermore, when it is desired to increase the cleanliness, the cleaning step may be repeatedly performed twice or more in one cleaning unit.
[0047]
In the slurry washing step, as described above, when a zeolite slurry is used as the slurry, the zeolite type conversion step can be performed by supplying a zeolite type conversion liquid instead of the cleaning liquid. Such a conversion step is preferably performed after the ordinary washing step. In addition, a gas can be supplied by the washing means 64 to stir a mixture of the liquid for mold conversion and the solid content of the slurry.
[0048]
(Solid content discharge process)
At a fixed position in the process execution area, the slurry processing section 4 that has completed the steps from slurry supply to washing is transported by the chain conveyor 200 to the solid content discharge step execution area, that is, the installation position of the discharge means 70. For example, as shown in FIG. 2, a discharging unit 70 that utilizes the fact that the slurry processing unit 4 is inverted at the end 200a of the conveyor 200 can be employed. The discharging means 70 is not limited to the one by such a reversing operation, but may be any one of conventionally known various means such as a discharging means by applying vibration or impact, or a discharging means by a scraper or the like. They can be used in combination of two or more kinds.
[0049]
(Slurry processing section cleaning process)
Further, by driving the chain conveyor 200, the slurry processing unit 4 reaches the cleaning process of the slurry processing unit 4, that is, the cleaning process execution area where the cleaning unit 80 of the processing unit 4 is arranged.
Various conventionally known means can be adopted as the cleaning means 80 of the processing section. For example, as shown in FIG. 2, a cleaning liquid such as water can be supplied into the slurry processing section 4 by spraying or the like, and the residue can be removed at once with pressure and water flow. In particular, in the present embodiment, since the slurry processing section 4 is in an inverted state, cleaning is facilitated. In this embodiment, it is preferable that a plurality of cleaning means 80 are provided.
[0050]
In addition to this mode or in place of this mode, a cleaning tank 90 in which the slurry processing unit 4 can move as shown in FIG. 2 can be adopted.
The slurry processing unit 4 moves inside the cleaning tank 90 with the opening facing downward, so that solids attached to the bottom and side surfaces of the slurry processing unit 4 settle on the bottom of the tank 90, and are cleaned. It can be deposited on the bottom of the tank 90. These deposits may be discharged as needed. The sediment can be moved to the accumulating section 92 by a screw conveyor or the like provided at the bottom of the cleaning tank 90 in parallel with the traveling direction of the slurry processing section 4. Also, by moving the opening edge of the slurry processing unit 4 near the bottom of the cleaning tank 90, the sediment is pushed by this edge along with the movement of the slurry processing unit 4 and the slurry processing unit 4 is moved. Can be moved in the moving direction. By providing the discharge part or the accumulation part 92 for deposits at the transfer destination (downstream side of the process), the inside of the cleaning tank can be constantly maintained in a state suitable for cleaning.
Further, by storing and transporting the sediment and using it as part or all of the slurry supplied to the slurry processing unit 4 and again performing solid-liquid separation again, the solid content can be recovered without waste. .
[0051]
After the cleaning process of the slurry processing unit 4 is completed, the slurry processing unit 4 is sent out again to the process execution area, and the above-described steps are repeatedly performed.
[0052]
In the above description, the configuration in which the processing means group 12 is moved from the process execution area has been described. However, the discharge means and the cleaning means may be moved or arranged in the process execution area.
[0053]
As described above, by performing the solid-liquid separation process for the slurry processing section group synchronously and sequentially, automatic operation is easy, and the production efficiency can be dramatically improved. In addition, dehydration efficiency and recovery efficiency can be easily increased without increasing energy cost.
[0054]
Incidentally, those skilled in the art, according to the common general technical knowledge in this field, to drive the slurry processing unit group in which the slurry processing unit in the present invention is arranged, and to drive the means group in which each step performing means is arranged, In addition to the above description, various modified forms can be easily created, and the present invention includes such modified forms and modified forms.
According to the present invention, there is also provided a method and an apparatus for dewatering and cleaning a slurry having the following constitution.
That is, the slurry is supplied, drained, supplied with a cleaning liquid, and supplied with a gas through the filter section into the cleaning mixture in a container-shaped slurry processing section having a filter section and capable of containing the slurry. A method and an apparatus are provided for agitating and washing the mixture and draining the washing mixture.
[0055]
【Example】
Hereinafter, a specific example of the present invention will be described. Note that these specific examples are for better explanation of the present invention and do not limit the present invention.
[0056]
(Example 1)
A coal-ash zeolite slurry having a temperature of 72 ° C., a solid concentration of 25 wt%, and a NaOH concentration of 1.4 N produced by a coal ash zeolite reactor is converted into a pan-like slurry processing section 5 having a length of 640 mm, a width of 440 mm and a depth of 150 mm. Each was supplied with 19.2 L / 96 L in total.
After the slurry was supplied, a dewatering and washing step of the slurry processing section was performed. In the dewatering step, the dewatering steps in all the processing sections were completed in a suction time of 20 seconds, and the pressure during suction showed 0.06 MPa. By this draining step, a cake having an average thickness of 30 mm was obtained.
In the stirring and washing step, 15 L (75 L in total) of hot water at 65 ° C. was supplied to each slurry processing section. Next, compressed air at a pressure of 0.08 MPa was sent for 25 seconds to stir the washing mixture. Thereafter, the washing mixture was suctioned and drained, and the draining steps of all the processing units were completed in 45 seconds. The pressure during suction was 0.06 MPa, and a dehydrated cake having an average thickness of 30 mm was obtained.
This washing step was repeated four times in total (300 L of the washing solution was compatible). The obtained cake had a residual moisture of 50.0%, and the pH of a 5 wt% slurry after drying the cake was 11.45. Was.
[0057]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the dewatering and washing apparatus and method of slurry which can implement | achieve high processing efficiency can be provided.
[Brief description of the drawings]
FIG. 1 is a diagram showing an outline of a slurry dewatering / cleaning step of the present invention.
FIG. 2 is a view schematically showing an overall configuration of a slurry dewatering / cleaning apparatus of the present invention.
FIG. 3 is a diagram showing a cross-sectional structure of a slurry processing unit in the present invention.
FIG. 4 is a diagram showing a structure when the slurry processing section of the present invention is viewed from above.
FIG. 5 is a cross-sectional view showing an example of a quantitative supply unit directed to each slurry processing unit in the slurry supply unit (cleaning liquid supply unit) of the present invention.
FIG. 6 is a plan view of an installation structure of a fixed amount supply unit shown in FIG.
FIG. 7 is a side view of the installation structure of the fixed amount supply unit shown in FIG.
FIG. 8 is a diagram showing a cross-sectional structure of an example of a slurry dewatering means (washing mixture dewatering means).
9 is a top view of the chamber shown in FIG. 8, showing a planar structure of a seal structure with a slurry processing unit. 1 Slurry dewatering and washing device
2 Slurry processing group
4 Slurry processing section
6 Filter
8 holes
10 Bottom plate
12 means group
14 Slurry supply means
16 Quantitative supply means
20 Slurry supply pipe
22 Supply pipe
24 float
28 valve
30 Buoyancy transmission mechanism
34 Slurry dewatering means
36 Reservoir
38 Suction chamber
40 sealing means
42 Sealing material
44 Cleaning liquid supply means
54 Washing mixture dewatering means
64 Cleaning means
70 discharging means
80 Slurry treatment section cleaning means
100 mount
110 Vertical mechanism
120 Support frame
200 conveyor

Claims (13)

A slurry dewatering and washing device,
A slurry processing unit group in which two or more slurry processing units are arranged independently of each other, each of which is capable of containing a slurry and having a filter, and
The following means arranged in connection with this slurry processing unit group:
Slurry dewatering means for suction-filtering the slurry contained in the slurry processing section through the filter,
A cleaning liquid supply unit that supplies a cleaning liquid to the processing unit after the liquid removal, and a cleaning mixture dewatering unit that suction-filters the cleaning mixture in the processing unit via the filter.
An apparatus comprising: The apparatus according to claim 1, wherein the means group further comprises a slurry supply means for supplying a slurry to the slurry processing section. 3. A quantitative supply unit having a valve mechanism for controlling supply of a slurry and / or a cleaning liquid to each of the slurry processing units in accordance with a height position of the surface of the content of each of the slurry processing units. An apparatus according to claim 1. The valve mechanism is provided corresponding to each of the slurry processing units, and is a float capable of generating buoyancy for the contents of each of the slurry processing units, and supplying a slurry and / or a cleaning liquid to each of the slurry processing units. 4. The apparatus according to claim 3, further comprising a valve that shuts off the supply of the supply target to the slurry processing unit when the float reaches a predetermined height position. The quantitative supply means is disposed along the slurry processing unit group, and corresponds to the arrangement position of each of the slurry processing units with respect to a pipe for supplying a cleaning liquid and / or slurry to each of the slurry processing units. Apparatus according to claim 3 or 4, provided. Each of the slurry processing units at a fixed position is sequentially and synchronously performed by the slurry dewatering unit, the cleaning liquid supply unit, and the cleaning mixture dewatering unit. The apparatus according to any one of claims 1 to 5. The apparatus according to claim 6, wherein, after the operations performed by the respective units performed in synchronization with each other, the slurry processing unit group moves to a slurry discharging step. The apparatus according to any one of claims 1 to 7, further comprising cleaning means for supplying a gas to the cleaning mixture in the slurry processing section to perform stirring cleaning. 9. The apparatus according to claim 8, wherein gas supply by said cleaning means is performed through said filter. The apparatus according to any one of claims 1 to 9, which is an apparatus for removing and washing a zeolite-containing slurry. The apparatus according to claim 10, further comprising means for supplying a zeolite-type conversion liquid to the slurry processing section. A method for washing and removing a slurry,
The following steps are performed for each slurry processing unit fixed at a fixed position in a slurry processing unit group including two or more slurry processing units each having a filter and being capable of storing a slurry, each of which is independent of each other;
(A) supplying a slurry to a slurry processing unit;
(B) a dewatering step of suction-filtering the slurry through the filter;
(C) a washing step of supplying a washing liquid to the residue after dewatering to wash the residue, and suction-filtering the washing mixture through the filter;
Are performed sequentially and synchronously. 13. The method according to claim 12, wherein in the cleaning step, after supplying the cleaning liquid, a gas is supplied to the slurry processing unit through the filter, and the cleaning liquid containing the residue is cleaned by gas stirring.

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