JP4319747B2 - Decanter centrifuge with rinse function - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a centrifugal separator with a rinsing function, more specifically, a rinsing zone for solid content and a filtration bush for promoting liquid removal on the wall surface which is a filtration zone, and a washing liquid for back washing of the filter medium on the filtrate discharge side The present invention relates to a decanter type centrifuge with a rinsing function provided with a supply pipe.
[0002]
[Prior art]
A decanter type centrifuge with a rinse function requires solid-liquid separation in a centrifugal field among intermediate products and products in the production process of foods, pharmaceuticals, etc., and washing of separated objects Is often used where it is needed immediately.
[0003]
As shown in FIG. 7, a conventional decanter centrifuge 100 with a rinsing function includes a frustoconical portion 101A and a rotating bowl 101 composed of a cylindrical portion 101B connected to the large-diameter end of the frustoconical portion 101A. And a screw conveyor 102 that is coaxially provided in the rotating bowl 101 and rotates with a slight differential speed, and an insertion tube hole 106 that protrudes into the center of the end plate 105 of the cylindrical portion 101B of the rotating bowl 101. The main part is composed of a supply pipe 107 that can supply the stock solution slurry and the rinsing liquid (cleaning liquid) to the predetermined positions in the rotating bowl 101 through the supply lines 107A and 107B.
[0004]
Next, an operation of the decanter type centrifuge 100 with the rinse function will be described. When the stock slurry is supplied to the separation zone shown in FIG. 7 in the rotating bowl 101 rotating at high speed, the solid content in the slurry is subjected to centrifugal force and settles on the inner wall side of the rotating bowl 101. The settled solid content is scraped up by the screw conveyor 102 toward the truncated cone portion 101A, and after being washed and drained in the beach zone by the rinse liquid (cleaning liquid) supplied to the beach zone simultaneously with the supply of the raw slurry. From the solid content outlet 108 provided on the small diameter end side of the truncated cone portion 101A, it is discharged to the outside as a washing cake.
On the other hand, the clarified liquid separated in the separation zone passes through the clarified liquid discharge port 104 provided in the end plate 105 of the cylindrical portion 101B of the rotating bowl 101, overflows the annular weir plate 103, and then is discharged to the outside as a separated liquid. Is done.
[0005]
[Problems to be solved by the invention]
However, in the conventional decanter centrifuge 100 with the rinsing function, the length of the beach zone is short and the space is small, so that sufficient washing time and drainage time of solids cannot be taken.
(1) When the particle size is relatively small (for example, 5 to 40 micrometers) and the solid content having poor cleaning properties and filterability is to be washed and dehydrated, the solid content that has been washed in the previous stage is retained in the beach zone. There is a problem that the cleaning effect of the solid content decreases due to re-adhering of dirt in the cleaning liquid. Moreover, since the drainage time was short, the solids drainage effect was not improved.
Therefore, as a cleaning method to solve this problem,
(A) As a method for increasing the cleaning effect, the solid content discharged from the solid content discharge port 108 is once received in a separate stirring tank containing a cleaning liquid and then reslurried to be cleaned.
(B) As a method for increasing the liquid removal effect, a method in which the reslurried liquid is further pumped up and again subjected to a high liquid removal treatment by a solid-liquid separator provided at a later stage
A tank replacement cleaning method is used.
In addition, as another cleaning method for solving this problem, a cleaning method in which a plurality of decanter type centrifuges 100 with a rinsing function are combined in series to perform cleaning processing and liquid removal processing in multiple stages, and the decanter with rinsing function are provided. A cleaning method is employed in which a cleaning process and a de-liquid process are performed in combination with a mold centrifuge and another solid-liquid separator.
However, both of these cleaning methods have a problem that not only the equipment cost and the operation cost are high, but also the installation space for the equipment becomes large.
And in order to raise the washing | cleaning effect of solid content, there existed a problem that an operating cost became high since the amount of rinse liquids had to be used in large quantities.
[0006]
The present invention has been made to solve the above-described problems, and provides a decanter type centrifuge with a rinsing function that has a good solids washing effect and liquid removal effect, has low equipment costs, and has a small installation space. The issue is to provide.
[0007]
[Means for Solving the Problems]
The gist of the invention described in claim 1 for solving the above-mentioned problem is that a truncated cone part having a solid content outlet on the small diameter end side and a large diameter end side of the truncated cone part are connected. A rotating bowl composed of a cylindrical portion having a clear liquid discharge port provided with an annular weir plate at the other end, and a screw conveyor provided coaxially in the rotating bowl and rotating at a slight differential speed, The cylindrical part is configured as a separation zone, and the frustoconical part is configured as a beach zone, and is inserted into an axial center part from an intubation hole of the cylindrical part end plate of the rotating bowl, and a raw liquid slurry supply pipe for supplying the raw liquid slurry to the separation zone And a decanter type centrifuge with a rinsing function that is inserted into the stock slurry supply pipe and that supplies a rinsing liquid to the beach zone. Of the cleaning solution pooling zone to said small-diameter end side from the large diameter end, configured as a rinse zone and filtration zone, the wall portion of the rinsing zone and the filtering zone, a plurality of for draining promoting Filter material was loaded into the hollow part A filtration bush is provided on the filtrate discharge side. Of the filtration bush A cleaning liquid supply pipe for reverse cleaning the filter medium is provided.
[0008]
The beach zone of the truncated cone part of the rotating bowl is configured as a cleaning liquid pool zone, a rinse zone and a filtration zone from the large diameter end side to the small diameter end side, and is held in the cleaning liquid pool zone formed on the solid content outlet side. The washing effect of the solid content is improved by two-stage washing including washing and replacement washing with a rinse solution in the rinse zone. Further, by providing a plurality of filtration bushes for promoting liquid removal on the wall surfaces of the rinse zone and the filtration zone, the washing liquid and the filtrate in the latter stage of the beach zone can be drained to the outside. The used rinsing liquid hardly stays in the rotating bowl, passes through the filter medium as it is, and immediately escapes to the outside. Therefore, the cleaning effect of the solid content is improved. Further, the liquid content contained in the solid content immediately becomes a filtrate and escapes to the outside, so that the liquid removal effect is improved. In addition, a single centrifuge with a rinse function can provide sufficient drainage and cleaning effects, eliminating the need for facilities such as agitation tanks and reslurry pumps, which were required in the past, and lowering equipment costs and installing equipment. Space can be reduced. In addition, the amount of rinse liquid required for cleaning can be reduced.
Furthermore, the clogging period of the filter medium can be extended by providing a cleaning liquid supply pipe for reverse cleaning on the filtrate discharge side of the filter medium provided in the filter bush and performing reverse cleaning. As a result, the operating time of the decanter centrifuge with the rinse function can be extended.
[0009]
The gist of the invention described in claim 2 for solving the above-described problem is that the truncated cone portion is reduced in diameter by two steps toward the solid content discharge port, The decanter type centrifuge with a rinsing function according to claim 1, wherein a head cone portion is configured as the rinsing zone and the filtration zone.
[0010]
By providing the truncated cone portion of the rotating bowl with a diameter reduced in two steps toward the solid content outlet, and providing a rinse zone and a filtration zone on the wall surface portion (inclined portion) of the second-stage truncated cone portion, Compared with the case where the rinsing zone and the filtration zone are provided on the horizontal wall surface portion, it is possible to suitably prevent the liquid after the cleaning treatment from going to the solid content outlet side. As a result, the cleaning effect and the liquid removal effect are also improved.
[0011]
The gist of the invention described in claim 3 for solving the above-mentioned problem is that a part of the small-diameter end side of the truncated cone portion has a small-diameter cylindrical portion toward the solid content outlet. The decanter centrifuge with a rinsing function according to claim 1, wherein the small-diameter cylindrical portion is configured as the rinse zone and the filtration zone.
[0012]
By providing a small-diameter cylindrical part on the small-diameter end side of the truncated cone part of the rotating bowl and configuring the rinse zone and the filtration zone, the washing time and the draining time can be lengthened. Compared with a decanter type centrifuge with a function, it is possible to improve the washing effect and the liquid removal effect of the solid content.
[0013]
The gist of the invention described in claim 4 for solving the above-mentioned problems is that the partition press plate is disposed at a position between the cleaning liquid pool zone and the rinse zone, and the liquid is removed at a position of the filtration zone. The rinsing according to any one of claims 1 to 3, wherein at least one press plate is erected in the axial direction between the screw blades of the screw conveyor with a certain distance from the inner wall of the rotating bowl. It is a decanter type centrifuge with a function.
[0014]
A partition press plate at the position between the cleaning liquid pool zone and the rinse zone and a depressurization press plate at the position of the filtration zone, respectively, and an axial center between the screw blades of the screw conveyor with a certain distance from the inner wall of the rotating bowl. By providing at least one or more in the direction, it is possible to further improve the cleaning effect and the liquid removal effect of the solid content coming out from the solid content outlet.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
A decanter centrifuge with a rinsing function according to the present invention will be described with reference to the embodiment shown in FIGS. FIG. 1 is a longitudinal sectional view showing a first embodiment of a decanter centrifuge with a rinsing function according to the present invention, FIG. 2 (a) is a longitudinal sectional view of a first embodiment of a filtration bush according to the present invention, 2 (b) is a longitudinal sectional view of a second embodiment of the filtration bush according to the present invention, FIG. 2 (c) is a longitudinal sectional view of a third embodiment of the filtration bush according to the present invention, and FIG. FIG. 4 is a longitudinal sectional view showing a second embodiment of a decanter type centrifuge with a rinse function according to the present invention, and FIG. 4 is a longitudinal sectional view showing a third embodiment of a decanter type centrifuge with a rinse function according to the present invention. FIG. 5 is a longitudinal sectional view showing a fourth embodiment of a decanter type centrifuge with a rinsing function according to the present invention, FIG. 6A is a perspective view of a partition press plate according to the present invention, and FIG. ) Is a perspective view of a depressurizing press plate according to the present invention.
[0016]
First, a first embodiment of a decanter centrifuge with a rinse function according to the present invention will be described with reference to FIG.
A decanter centrifuge 1 with a rinsing function according to the present invention includes:
A truncated cone portion 2b having a solid content discharge port 9 on the small diameter end side and provided with a plurality of filtration bushes f1, f2, f3 on the inclined wall surface portion 2a on the small diameter end side, and the truncated cone portion 2b A rotating bowl 2 comprising a large-diameter cylindrical portion 2c having a clarified liquid discharge port 4 provided continuously with the large-diameter end side and provided with an annular weir plate 3 on the end plate 6 which is the other end;
A screw blade 5a provided coaxially in the rotary bowl 2, rotated at a slight differential speed (for example, 5 to 50 rpm), and spirally surrounded and fixed around the screw shaft 5b; and the rotary bowl 2 And a hollow screw shaft 5b having a slurry distribution port 5c provided in a separation zone which is a large-diameter cylindrical portion 2c and a rinsing liquid distribution port 5d provided over a filtration zone and a rinse zone of the truncated cone portion 2b. A screw conveyor 5 in which the section is configured;
The raw solution slurry supply pipe 8a that is inserted through the intubation hole 7 projecting into the center of the end plate 6 of the rotating bowl 2 and extends to the separation zone, and the cleaning liquid that is inserted into the raw solution slurry supply pipe 8a and extends to the rinse zone of the beach zone. A liquid supply pipe 8 composed of a supply pipe 8b;
Cleaning liquid supply pipes BW1, BW2, BW3 for backwashing disposed opposite to the filtrate discharge side of the filtration bushes f1, f2, f3
The main part is composed of
[0017]
Next, the operation of the centrifuge 1 with the rinse function configured as described above will be described.
The raw slurry is supplied to the separation zone in the rotating bowl 2 rotating at a high speed (for example, 3000 to 5000 rpm), and the rinsing liquid (cleaning liquid) is supplied to a predetermined position through the supply pipes 8a and 8b. The solid content in the slurry supplied to the separation zone from the slurry distribution port 5c is subjected to centrifugal force and settles on the inner wall side of the large-diameter cylindrical portion 2c of the rotating bowl 2. The settled solid content is scraped up by the screw blade 5a of the screw conveyor 5 toward the truncated cone portion 2b, preliminarily held and washed in the washing liquid pool zone, and further provided with a plurality of filtration bushes f1, f2, and f3. It is conveyed to the inclined wall surface portion 2a on the small diameter end side. Here, the above-mentioned hold cleaning means that the solid content is cleaned while being conveyed by the screw conveyor 5 in the cleaning solution accumulated in the cleaning solution pool zone.
The solid content suitably washed and drained by the action of the filtration bushes f1, f2, and f3, which will be described later, on the inclined wall surface portion 2a in the truncated cone portion 2b is a solid provided on the small diameter end side of the truncated cone portion 2b. It is discharged to the outside as a washing cake from the minute discharge port 9.
On the other hand, the clarified liquid separated in the separation zone flows through the clarified liquid discharge port 4 provided in the end plate 6 of the large-diameter cylindrical portion 2c of the rotating bowl 2, overflows the annular weir plate 3, and is discharged to the outside as a separated liquid. Is done.
When the filtration bushes f1, f2, and f3 are closed, the rotational speed of the rotary bowl 2 is lowered, and the washing liquid supply pipe BW1 for backwashing provided opposite to the filtrate discharge side of the filtration bushes f1, f2, and f3. , BW2 and BW3 can be sprayed and the filter medium can be backwashed to eliminate clogging.
By doing so, clogging of the filter medium can be reduced, and the operation operation time of the decanter type centrifuge with a rinse function can be extended.
[0018]
The partition plate 10 shown in FIG. 1 is a plate member installed to separate the separation zone and the beach zone, and the cleaning liquid is supplied to the cleaning liquid pool zone configured on the solid content outlet 9 side of the partition plate 10. This is for forming a pool and preliminarily holding and washing the solid content. Here, the hold cleaning means that the solid content is cleaned while being conveyed by the screw conveyor 5 in the cleaning solution accumulated in the cleaning solution pool zone.
[0019]
Next, the configuration and operation of the filtration bushes f1, f2, and f3 according to the present invention will be described with reference to FIG.
The filtration bushes f1, f2, and f3 according to the present invention are provided on the inclined wall surface 2a on the small diameter end side of the frustoconical portion 2b of the rotary bowl 2 that is the rinse zone and the filtration zone of the decanter centrifuge 1 with the rinse function. A plurality of screw holes are provided in a plurality of rows, and the hollow portion of the bush is loaded with a filter medium and screwed into the plurality of screw holes in a plurality of rows. Note that the hollow portion of the bush is configured so that a filter medium can be loaded in the upper portion and a space can be secured in the lower portion in order to improve the drainage of the filtrate. The number of filter bushes f1, f2, and f3 varies greatly depending on the properties of the solid content, but usually 6 to 18 are provided.
[0020]
FIG. 2A is a longitudinal sectional view showing a first embodiment of the filtration bushes f1, f2, and f3, and a sintered metal SM manufactured by powder metallurgy on a support member ST1 (for example, a perforated plate) is used as a filter medium. It is loaded in the hollow part of the bush BS1. Depending on the properties of the treated material, not only the sintered metal SM but also a ceramic filter material or a plastics filter material can be used as the filter medium. This filtration bush BH1 is suitable for filtering a treated product having a small average particle size of solid content (for example, 5 to 20 micrometers) and poor filterability. SP1 is a screw portion for screwing the main filtration bush BH1 to the inclined wall surface portion 2a of the truncated cone portion 2b.
[0021]
FIG. 2B is a longitudinal sectional view showing a second embodiment of the filtration bushes f1, f2, and f3. The bush BS2 has a filter cloth FC as a filter medium on the support member ST2 (for example, a stainless steel wire mesh). It is loaded in the hollow part. The present filtration bush BH2 is suitable for filtering a processed product having a relatively large average particle size of a solid content (for example, 20 to 40 micrometers) and poor filterability. In addition, SP2 is a screw part for screwing this filtration bush BH2 to the inclined wall surface part 2a of the truncated cone part 2b.
[0022]
FIG. 2C is a longitudinal sectional view showing a third embodiment of the filtration bushes f1, f2, and f3, and is a filter wire mesh on a support member ST3 (for example, a member having a ceramic hole). The screen WS is used as a filter medium and is loaded in the hollow portion of the bush BS3. This filtration bush BH3 is suitable for filtering a treated product having a large average particle size of solid content (for example, 40 micrometers to several millimeters) and poor filterability. Note that SP3 is a screw portion for screwing the main filtration bush BH3 onto the inclined wall surface portion 2a of the truncated cone portion 2b.
[0023]
Next, the operation of the filtration bushes f1, f2, and f3 according to the present invention will be described with reference to FIG.
The solid content separated in the separation zone of the rotating bowl 2 and transported to the beach zone by the screw conveyor 5 is preliminarily held and washed in the cleaning liquid pool zone, and then provided with the filtration bushes f1, f2, and f3 according to the present invention. It is conveyed to the rinse zone and the filtration zone.
[0024]
First, the solid content passes over a filtration bush f3 provided in a rinse zone where countercurrent washing is performed with a rinse liquid. Here, dirt that is relatively easy to remove from the solid content is washed and removed. From the filtration bush f3, the liquid after the cleaning process having substantially the same composition as the unused rinse liquid is discharged as the filtrate.
[0025]
Next, the solid content passes over a filtration bush f2 provided at a lower portion of the rinse liquid distribution port 5d for showering the rinse liquid. Here, the solid content cleaning effect can be further improved by strongly cleaning the solid content that is difficult to be removed with a large amount of cleaning liquid showered with kinetic energy.
[0026]
During this time, since the liquid after the washing process is suitably discharged from the filtration bush f2 to the filtrate discharge side, the liquid after the washing process including dirt does not stay in the solids washing region. As a result, the solid content is always washed with a new rinse solution, and the solid content cleaning effect is improved.
[0027]
Furthermore, solid content is conveyed on the filtration bush f1 provided in the filtration zone. Here, the liquid content (for example, (1) air gap liquid, (2) wedge capillary liquid, (3) adhering liquid, (4) adsorbing liquid, etc.) contained in the solid content that has obtained a sufficient cleaning effect in the previous stage is mainly removed. This is a zone for liquefying, and the liquid content contained in the solid content is separated by centrifugal force and immediately discharged to the outside through the filtration bush f1, so that it is sufficiently drained even in a short time, and the solid content is drained. The effect is improved.
[0028]
Since the washability and filterability differ depending on the type of stock slurry, a plurality of rows of filtration bushes f1, f2, and f3 are provided on the inclined wall surface portion 2a from the beginning, and the filtration bushes f1, f2, and f3 are provided. If a blind plate is provided, the cleaning state and the liquid removal state can be controlled by the position and number of the filter bushes f1, f2, and f3 incorporated. As a result, many types of stock solution slurries can be processed with one decanter centrifuge with a rinse function.
[0029]
Thus, the beach zone which is the truncated cone portion 2b of the rotating bowl 2 is made longer than the conventional length, and is configured as a cleaning liquid pool zone, a rinse zone and a filtration zone from the large diameter end side to the small diameter end side, A plurality of filtration bushes f1, f2, f3 for promoting liquid removal are provided on the inclined wall surface portion 2a of the rinse zone and the filtration zone, and a washing liquid supply pipe BW1, for reversely washing the filter medium facing the filtrate discharge side By providing BW2 and BW3, not only the optimum washing effect and liquid removal effect of the solid content can be obtained, but also the operating time of the decanter type centrifuge with a rinsing function can be extended.
[0030]
Next, a second embodiment of the decanter centrifuge with a rinse function according to the present invention will be described with reference to FIG. In addition, about the same member as the decanter type centrifuge 1 with the rinse function of 1st embodiment, the same code | symbol is attached and the overlapping description is abbreviate | omitted.
The centrifuge 1 'with the rinse function is such that the truncated cone portion 2'b is reduced in diameter by two steps toward the solid content outlet 9 (a small truncated cone portion 2'a and a large truncated cone portion). 2′b is a continuous arrangement) and the second stage truncated cone portion 2′a is configured as a rinse zone and a filtration zone.
[0031]
The frustoconical part of the rotating bowl is provided with a reduced diameter in two steps toward the solid content outlet 9 (the small frustoconical part 2'a and the large frustoconical part 2'b are connected in series, and the beach zone When the rinse zone and the filtration zone are provided on the horizontal wall surface portion by providing the rinse zone and the filtration zone on the wall surface portion (inclined portion) of the second stage truncated cone portion 2'a In comparison, it is possible to suitably prevent the liquid after the cleaning treatment from being accompanied by the solid content and going to the solid content outlet 9 side. As a result, it is possible to improve the solids washing effect and liquid removal effect.
[0032]
Next, a third embodiment of the decanter centrifuge with a rinsing function according to the present invention will be described with reference to FIG. In addition, about the same member as the decanter type centrifuge 1 with the rinse function of 1st embodiment, the same code | symbol is attached and the overlapping description is abbreviate | omitted.
The centrifuge 1 ″ with the rinse function has a small-diameter cylindrical portion 2 ″ a in which a part on the small-diameter end side of the truncated cone portion 2 ″ b has a small-diameter cylindrical portion 2 ″ a toward the solid content discharge port 9. The cylindrical portion 2 ″ a is configured as a rinse zone and a filtration zone.
[0033]
A small-diameter cylindrical portion 2 ″ a is provided at a part of the small-diameter end side of the truncated cone portion 2 ″ b of the rotating bowl 2 ″ to lengthen the beach zone, and the small-diameter cylindrical portion 2 ″ a is rinsed and filtered. By configuring the zone, the washing time and the drainage time can be lengthened, so that the solid content washing effect and the draining effect can be achieved as compared with the conventional decanter centrifuge 100 with the rinse function (see FIG. 7). Can be improved.
[0034]
Next, with reference to FIG. 5, 4th embodiment of the decanter type centrifuge with a rinse function which concerns on this invention is described. The same members as those in the decanter type centrifuge 1 with the rinse function of the first embodiment are denoted by the same reference numerals.
The structure of the decanter type centrifuge with the rinse function of the present invention is such that the shaft between the screw blades 5a of the screw conveyor 5 is spaced from the inner wall of the rotating bowl 2 of the decanter type centrifuge 1 with the rinse function of the first embodiment. At least one or more partitioning press plates 11 and drainage press plates 12 are erected in the center direction.
[0035]
The configuration and action of the partition press plate 11 and the liquid removal press plate 12 will be described with reference to FIG.
The partition press plate 11 is a water-impermeable plate material for isolating the rinse zone of the beach zone and the preceding cleaning liquid pool zone. As shown to Fig.6 (a), it is fixed to the screw shaft 5b which has the hollow part of the screw conveyor 5 with a volt | bolt, and stands upright. The main body WM15 is made of a fine metal mesh made of stainless steel, the corners RP are made of soft rubber, and the tip portion HC1 bent in the counter-rotating direction of the screw shaft 5b is subjected to processing for improving wear resistance. ing.
[0036]
When the partition press plate 11 rotates integrally with the screw shaft 5b of the screw conveyor 5, the solid content preliminarily held and washed in the cleaning liquid pool zone is compressed into the main body WM15 of the partition press plate 11, and the liquid in the stock slurry It is possible to reduce the amount of the minute accompanying the solid content. By doing in this way, since the amount of the rinse liquid in the rinse zone required for washing | cleaning of solid content can further be reduced rather than the decanter type centrifuge 1 with a rinse function of 1st embodiment, the cost reduction of an operating cost can be achieved. .
[0037]
On the other hand, the depressurizing press plate 12 is a water-permeable plate material provided in the filtration zone to separate the filtration zone from the previous rinse zone. As shown in FIG.6 (b), it fixes to the screw shaft 5b which has the hollow part of the screw conveyor 5 with a volt | bolt, and is erected vertically. The main body WM50 is made of a stainless steel rough wire mesh, both corners PB are made of a press plate, and the tip HC2 bent in the counter-rotating direction of the screw shaft 5b is processed to improve wear resistance for edging. It has been subjected.
[0038]
The dewatering press plate 12 is a water-permeable plate material provided in the filtration zone, and when rotated integrally with the screw shaft 5b of the screw conveyor 5, the solid content sufficiently cleaned of dirt in the rinsing zone is used for dewatering. The liquid component pressed by the wire mesh which is the main body WM50 of the press plate 12 and accompanying the solid content can be suitably drained. By squeezing in this way, in the filtration zone, only the liquid that is difficult to drain can be drained over time, so the draining effect is improved.
[0039]
According to the above configuration and operation, the axial direction between the screw conveyor 5 of the decanter type centrifugal separator 1 with the rinse function and the inner wall of the rotary bowl 2 of the first embodiment and the screw blades 5a of the screw conveyor 5 with a certain distance. Further, by providing at least one of the partition press plate 11 and the liquid removal press plate 12 in a standing state, the solid content cleaning effect and removal can be further improved as compared with the decanter centrifuge 1 with the rinse function of the first embodiment. The liquid effect can be improved.
[0040]
As described above, the beach zone of the rotating bowl of the conventional decanter centrifuge with the rinse function is lengthened, and the cleaning liquid pool zone, the rinse zone, and the filtration zone are moved from the large diameter end side to the small diameter end side of the truncated cone portion. By providing a plurality of filtration bushes for promoting liquid removal on the wall surfaces of the rinse zone and the filtration zone, it is possible to install solid components with a good cleaning effect and liquid removal effect and at low equipment costs. A decanter centrifuge with a rinse function with a small space can be provided.
Furthermore, by providing at least one or more partition press plates and dewatering press plates in the axial direction between the screw conveyor and the screw blades of the screw conveyor at a certain distance from the inner wall of the screw conveyor and the rotary bowl, The decanter type centrifuge with a rinse function that can further improve the washing effect and the liquid removal effect of the solid content than the decanter type centrifuge with the rinse function of the embodiment can be provided.
[0041]
【The invention's effect】
According to the present invention having the above configuration and operation,
1) A plurality of filtration bushes for promoting liquid removal are provided on the wall surface on the small-diameter end side of the truncated cone portion of the rotating bowl to improve the drainage of the washing liquid and the filtrate in the subsequent stage of the beach zone. The rinsing liquid used in the above is hardly accumulated in the rotating bowl, passes through the filter medium as it is, and immediately escapes to the outside. Therefore, the cleaning effect of the solid content is improved.
2) Also, liquids contained in the solid content that are relatively easy to drain will be drained by the preceding filtration bush, so that the liquid that is difficult to drain is removed by taking the time with the subsequent filtering bush. Can be liquid. Therefore, the liquid removal effect is also improved.
3) Therefore, since a sufficient washing effect and liquid removal effect can be obtained with only one centrifuge with a rinsing function, facilities such as a stirring tank and a reslurry pump, which have been necessary in the past, are not required, resulting in an increase in equipment cost. It becomes inexpensive and the installation space for equipment can be reduced.
4) Moreover, the clogging period of the filter medium can be extended by providing a liquid supply pipe for backwashing on the filtrate discharge side of the filter medium provided in the filter bush and backwashing. As a result, the operating time of the decanter centrifuge with the rinse function can be extended.
5) Further, a partition press plate at the position between the cleaning liquid pool zone and the rinse zone and a depressurization press plate at the position of the filtration zone, and between the screw blades of the screw conveyor at a certain distance from the inner wall of the rotating bowl, respectively. By providing at least one or more in the axial direction, it is possible to further improve the cleaning effect and the draining effect of the solid content coming out of the solid content outlet.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a first embodiment of a decanter centrifuge with a rinse function according to the present invention.
FIG. 2 (a) is a longitudinal sectional view of a first embodiment of a filtration bush according to the present invention.
(B) It is a longitudinal cross-sectional view of 2nd embodiment of the filtration bush concerning this invention.
(C) It is a longitudinal cross-sectional view of 3rd embodiment of the filtration bush concerning this invention.
FIG. 3 is a longitudinal sectional view of a second embodiment of a decanter centrifuge with a rinsing function according to the present invention.
FIG. 4 is a longitudinal sectional view of a third embodiment of a decanter centrifuge with a rinsing function according to the present invention.
FIG. 5 is a longitudinal sectional view of a fourth embodiment of a decanter centrifuge with a rinsing function according to the present invention.
FIG. 6A is a perspective view of a partition press plate according to the present invention.
(B) It is a perspective view of the press plate for liquid removal which concerns on this invention.
FIG. 7 is a longitudinal sectional view of a conventional decanter centrifuge with a rinse function.
[Explanation of symbols]
1 Decanter centrifuge with rinse function
2 Rotating bowl
2a Inclined wall
2b truncated cone
2c Large diameter cylindrical part
3 Annular dam plate
4 Clear liquid outlet
5 Screw conveyor
5a Screw blade
5b Screw shaft
5c Slurry distribution port
5d Rinse solution (cleaning solution) distribution port
6 End plate
7 Intubation hole
8 Liquid supply pipe
8a Stock solution slurry supply pipe
8b Rinse solution (cleaning solution) supply pipe
9 Solids outlet
10 Bulkhead plate
11 Partition press plate
12 Press plate for liquid removal
f1 to f3 Filtration bush
BW1 to BW3 Cleaning liquid supply piping for reverse cleaning

Claims (4)

Rotation comprising a truncated cone part having a solid content outlet on the small diameter end and a cylindrical part having a clarified liquid outlet connected to the large diameter end side of the truncated cone part and provided with an annular weir plate at the other end And a screw conveyor provided coaxially in the rotating bowl and rotating at a slight differential speed, wherein the cylindrical portion is configured as a separation zone and the truncated cone portion is configured as a beach zone, A stock solution slurry supply pipe that is inserted into the shaft center portion from the intubation hole of the cylindrical end plate and supplies the stock solution slurry to the separation zone, and a rinse solution that is inserted through the stock solution slurry supply pipe and supplies the rinse solution to the beach zone In the decanter centrifuge with the rinse function composed of the supply pipe,
The beach zone is configured as a cleaning liquid pool zone, a rinse zone, and a filtration zone from the large-diameter end side to the small-diameter end side of the truncated cone portion, and a plurality of liquid removals are provided on the rinse zone and the wall surface of the filtration zone. A decanter type centrifugal separator with a rinsing function, characterized in that a filter bush loaded with a filter medium is provided in a hollow portion for promotion, and a cleaning liquid supply pipe for back cleaning the filter medium of the filter bush is provided on the filtrate discharge side. Machine. The said truncated cone part is diameter-reduced to 2 steps | paragraphs toward the said solid content discharge port, The 2nd stage truncated cone part was comprised as the said rinse zone and the said filtration zone, It is characterized by the above-mentioned. A decanter centrifuge with a rinse function as described in 1. A part of the small-diameter end side of the truncated cone portion has a small-diameter cylindrical portion toward the solid content discharge port, and the small-diameter cylindrical portion is configured as the rinse zone and the filtration zone, The decanter type centrifuge with a rinsing function according to claim 1. A partition press plate at a position between the cleaning liquid pool zone and the rinse zone, and a depressurization press plate at a position of the filtration zone, and between the screw blades of the screw conveyor with a certain distance from the inner wall of the rotary bowl, respectively. The decanter type centrifuge with a rinsing function according to claim 1, wherein at least one of the decanter type centrifuges is erected in the axial direction.

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