JP7730730B2 - Gypsum recovery equipment - Google Patents

Description

This disclosure relates to a gypsum recovery device that dehydrates gypsum slurry and recovers gypsum.

Gypsum recovery devices that dehydrate gypsum slurry while transporting it and recover the gypsum have been known for some time. For example, Patent Document 1 discloses a gypsum recovery device that uses steam to heat the gypsum slurry while it is being transported in order to improve dehydration performance.

Japanese Patent Application Laid-Open No. 2021-074660

However, with the technology described in Patent Document 1, there is a risk that the steam sprayed onto the gypsum slurry may leak, inhibiting the improvement in dewatering performance due to the temperature increase of the gypsum slurry.

This disclosure was made in consideration of the above-mentioned issues, and aims to provide a gypsum recovery device that can improve dewatering performance.

To achieve the above-mentioned objective, the gypsum recovery device disclosed herein is a gypsum recovery device for dehydrating gypsum slurry to recover gypsum, and includes a conveying device configured to convey the gypsum slurry on a filter cloth, a steam nozzle disposed above the filter cloth for spraying steam onto the gypsum slurry being conveyed by the conveying device, at least one steam box configured to cover the steam nozzle and the space surrounding it, and a hood configured to cover the at least one steam box.

The gypsum recovery device disclosed herein can improve dewatering performance.

1 is a diagram schematically illustrating a configuration of a gypsum recovery device according to a first embodiment. FIG. 6 is a cross-sectional view of a main part of a gypsum recovery device according to a second embodiment. FIG. 10 is a diagram illustrating a schematic configuration of a hood according to a second embodiment. FIG. 10 is a diagram for explaining a configuration for supplying steam to a steam nozzle according to a second embodiment.

The following describes a gypsum recovery device according to an embodiment of the present disclosure, with reference to the drawings. This embodiment represents one aspect of the present disclosure and does not limit the disclosure, and can be modified as desired within the scope of the technical concept of the present disclosure.

First Embodiment
(composition)
1 is a diagram schematically illustrating a configuration of a gypsum recovery apparatus 1 according to a first embodiment. The gypsum recovery apparatus 1 according to the present disclosure is an apparatus for dehydrating a gypsum slurry X1 to recover gypsum X2. The gypsum recovery apparatus 1 dehydrates the gypsum slurry X1, which is a by-product of a wet flue gas desulfurization apparatus for desulfurizing exhaust gas discharged from a combustion facility such as a boiler, and recovers the gypsum X2.

As illustrated in FIG. 1, the gypsum recovery device 1 according to the first embodiment includes a conveying device 2, a steam nozzle 4, a steam box 6, and a hood 8.

The conveying device 2 conveys the gypsum slurry X1 placed on the filter cloth 10. In the embodiment illustrated in FIG. 1, the conveying device 2 includes a conveying belt 50, two rotatably supported drums 52, a motor 54 connected to one of the two drums 52, one-side drum 52A (52), and configured to rotate the one-side drum 52A, and a plurality of guide rollers 56. The conveying belt 50 is made of an endless band-shaped rubber member (elastic body) and is freely stretched around the two drums 52 arranged apart in the horizontal direction. Because the conveying belt 50 is stretched across the two drums 52, when one-side drum 52A is rotated by the motor 54, the other-side drum 52B (52) rotates and the conveying belt 50 moves around.

The filter cloth 10 is provided in the form of an endless belt, stretched freely around multiple guide rollers 56, and partially overlaps the top surface of the conveyor belt 50 in its longitudinal direction. Therefore, when the conveyor belt 50 rotates, the filter cloth 10 also rotates. The filter cloth 10 is not particularly limited as long as it is breathable, but it may include, for example, a woven fabric formed by weaving together a fibrous resin material (such as polyester or polypropylene). In some embodiments, the filter cloth 10 includes a nonwoven fabric formed by intertwining a fibrous resin material (such as polyester or polypropylene).

In the embodiment illustrated in FIG. 1, the gypsum recovery device 1 is configured so that gypsum slurry X1 is supplied onto a portion of the filter cloth 10 that is layered on the upper surface of the conveyor belt 50. The gypsum recovery device 1 is configured to dehydrate the gypsum slurry X1 as it is transported together with the filter cloth 10 by the conveyor belt 50. Here, an example of the configuration of the gypsum recovery device 1 for dehydrating the gypsum slurry X1 will be described.

As illustrated in FIG. 1, the gypsum recovery device 1 is provided below the conveyor belt 50 on the opposite side of the conveyor belt 50 from the filter cloth 10, and includes a dehydration chamber 58 whose internal pressure is maintained at a negative pressure (a pressure lower than atmospheric pressure), a vacuum pump 60, a reduced pressure line 62 connected at one end to the dehydration chamber 58 and at the other end to the vacuum pump 60, and a vacuum tank 64 provided on the reduced pressure line 62.

By operating the vacuum pump 60, the dehydration chamber 58 is depressurized to a negative pressure, and the moisture in the gypsum slurry X1 placed on the filter cloth 10 is forcibly sucked from below, dehydrating the gypsum slurry X1. The moisture dehydrated from the gypsum slurry X1 is sent from the dehydration chamber 58 to the vacuum tank 64 as filtrate X3 by operating the vacuum pump 60. The vacuum tank 64 has a drain port 65 formed at the bottom so that the filtrate X3 can be discharged from the vacuum tank 64. The gypsum X2 obtained by dehydrating the gypsum slurry X1 is removed from the filter cloth 10 downstream of the dehydration chamber 58 in the conveying direction D1 of the gypsum slurry X1. Although not shown, the conveyor belt 50 has multiple holes formed therein to allow the moisture in the gypsum slurry X1 to pass through.

Hereinafter, the conveying direction D1 of the gypsum slurry X1 will be referred to as the "conveying direction D1," the direction perpendicular to the conveying direction D1 will be referred to as the "crossing direction D2," and the direction perpendicular to both the conveying direction D1 and the crossing direction D2 will be referred to as the "vertical direction D3." The conveying direction D1 may also be referred to as the longitudinal direction of the conveyor belt 50. The crossing direction D2 may also be referred to as the width direction of the conveyor belt 50. The downward direction of the vertical direction D3 may also be referred to as the direction of gravity.

Next, we will explain the steam nozzle 4, steam box 6, and hood 8.

The steam nozzle 4 is positioned above the filter cloth 10 and sprays steam S onto the gypsum slurry X1 being transported by the transport device 2. The steam nozzle 4 is supplied with steam S from, for example, a boiler (not shown). The steam nozzle 4 then sprays this steam S onto the gypsum slurry X1 being transported, thereby raising the temperature of the gypsum slurry X1.

The gypsum recovery apparatus 1 may be equipped with multiple steam nozzles 4. In some embodiments, the number of steam nozzles 4 equipped in the gypsum recovery apparatus 1 is determined based on the supply amount of steam S and the opening area of the steam nozzles 4. For example, the number of steam nozzles 4 is increased by one until the quotient obtained by dividing the supply amount of steam S supplied from a boiler or the like by the total opening area becomes smaller than a preset value. In some embodiments, the opening area of the steam nozzles 4 is increased until the quotient becomes smaller than the set value.

The steam box 6 is configured to cover the steam nozzle 4 and the steam spray space 7, which is the space around it. The steam box 6 has a box shape that opens toward the filter cloth 10, and the steam S sprayed from the steam nozzle 4 inside the steam box 6 passes through the opening of the steam box 6 and collides with the gypsum slurry X1 on the filter cloth 10. In the first embodiment, the gypsum recovery device 1 is equipped with one steam box 6.

While the gypsum recovery apparatus 1 includes one steam box 6 in the first embodiment, the present disclosure is not limited to this configuration. In some embodiments, the gypsum recovery apparatus 1 includes multiple steam boxes 6. In some embodiments, the gypsum recovery apparatus 1 includes multiple steam boxes 6, each of which is standardized to the same dimensions and shape and modularly designed. The number of steam boxes 6 is determined based on the residence time of the steam S in the steam box 6 and the dehydration time calculated from the speed of the conveyor belt 50 and the length of the dehydration section in which the gypsum slurry X1 is dehydrated. For example, the number of steam boxes 6 is added one by one until the value obtained by dividing the residence time by the dehydration time becomes smaller than a preset value. With this configuration, the modular design of the steam boxes 6 makes it possible to accommodate changes in the required processing volume of the gypsum slurry X1 or the specifications of the gypsum recovery apparatus 1 by simply adding one or two steam boxes 6 without having to individually design the dimensions and shape of each steam box 6, thereby simplifying the design.

The hood 8 is configured to cover the steam box 6 and the inflow space 9, which is the space around it. In the example shown in Figure 1, the hood 8 has a box shape that opens toward the filter cloth 10, so that all or most of the steam S that flows out from the steam spray space 7 of the steam box 6 flows into the inflow space 9 of the hood 8.

As illustrated in FIG. 1, in the first embodiment, the gypsum recovery device 1 further includes a notch forming device 70 capable of forming notches in the surface of the gypsum slurry X1 being transported by the transport device 2. The notch forming device 70 is disposed upstream of the hood 8 in the transport direction D1.

(Actions and Effects)
According to the first embodiment, as illustrated in FIG. 1 , the steam nozzle 4 is covered by the steam box 6, and the steam box 6 is covered by the hood 8 (i.e., the steam nozzle 4 is doubly covered), thereby suppressing leakage of the steam S to the outside of the hood 8. As a result, the steam S sprayed from the steam nozzle 4 can be retained in the steam box 6, accelerating the temperature increase of the gypsum slurry X1. Therefore, it is possible to provide a gypsum recovery device 1 capable of improving dehydration performance. Furthermore, according to the first embodiment, since leakage of the steam S is suppressed, the amount of steam S supplied to the steam nozzle 4 can be increased, and the temperature of the gypsum slurry X1 can be easily increased to a temperature suitable for dehydration (e.g., 60°C to 70°C).

According to the first embodiment, as illustrated in FIG. 1, the notch forming device 70 is positioned upstream of the hood 8 in the conveying direction D1. As a result, the temperature of the gypsum slurry X1 is raised by the steam S after the surface film is destroyed, making it easier to raise the temperature of the gypsum slurry X1 compared to when the surface film is not destroyed, thereby improving dewatering performance.

Second Embodiment
A gypsum recovery apparatus 1 according to a second embodiment of the present disclosure will be described. The gypsum recovery apparatus 1 according to the second embodiment includes a plurality of steam boxes 6. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

(composition)
Fig. 2 is a cross-sectional view of a main part of a gypsum recovery apparatus 1 according to a second embodiment, and schematically shows a cross section along the conveying direction D1 of a hood 8. As illustrated in Fig. 2, in the second embodiment, the gypsum recovery apparatus 1 includes a plurality of steam boxes 6. One hood 8 covers each of the plurality of steam boxes 6. In other words, a plurality of steam boxes 6 are arranged in the inflow space 9 of one hood 8.

An example of the configuration of the hood 8 will now be described. Figure 3 is a diagram schematically illustrating the configuration of the hood 8 according to the second embodiment, showing the hood 8 as viewed from above (top view).

As illustrated in FIG. 2, in the second embodiment, the hood 8 includes a front plate 12 extending in the vertical direction D3, a rear plate 14 located downstream of the front plate 12 in the conveying direction D1 and extending in the vertical direction D3, and a top plate 15 connecting an upper end 13 of the front plate 12 to an upper end 17 of the rear plate 14. As illustrated in FIG. 3, the hood 8 also includes a plate-shaped one-side side plate 16 connecting the ends of the front plate 12 and the rear plate 14 on one side in the transverse direction D2, and a plate-shaped other-side side plate 18 connecting the ends of the front plate 12 and the rear plate 14 on the other side in the transverse direction D2. The front plate 12, rear plate 14, top plate 15, one-side side plate 16, and other-side side plate 18 that constitute the hood 8 may be integrally formed of metal as a single component.

As illustrated in FIG. 2, in the second embodiment, the multiple steam boxes 6 include a first steam box 6A (6), a second steam box 6B (6), and a third steam box 6C (6), arranged in this order from upstream to downstream in the conveying direction D1. In other words, the second steam box 6B is arranged downstream of the first steam box 6A in the conveying direction D1. The third steam box 6C is the most downstream steam box of the first steam box 6A, second steam box 6B, and third steam box 6C, and is arranged furthest downstream in the conveying direction D1.

The first steam box 6A and the second steam box 6B are arranged adjacent to each other. A gap 26 is formed between the first steam box 6A and the second steam box 6B. This gap 26 is designed, for example, to have a length of 10 cm or less in the conveying direction D1. In some embodiments, the first steam box 6A and the second steam box 6B are arranged adjacent to each other along the conveying direction D1 and are in contact with each other. This configuration prevents steam S from passing between the first steam box 6A and the second steam box 6B and flowing into the inflow space 9 of the hood 8.

Here, an example of a configuration for supplying steam S to each of the first steam nozzle 4A (4) covered by the first steam box 6A, the second steam nozzle 4B (4) covered by the second steam box 6B, and the third steam nozzle 4C (4) covered by the third steam box 6C will be described. Figure 4 is a diagram illustrating the configuration for supplying steam S to the steam nozzle 4 according to the second embodiment.

As illustrated in FIG. 4 , in the second embodiment, the gypsum recovery device 1 further includes a steam pipe 20 through which steam S flows, and a steam header 24 that connects the steam pipe 20 to the steam nozzle 4 and allows the flow of steam S. One end 21 of the steam pipe 20 is connected to a steam generating device 100 that generates steam S, such as a boiler. The other end 23 of the steam pipe 20 is located within the hood 8 (within the inflow space 9 of the hood 8). In other words, a portion of the steam pipe 20, including the other end 23 of the steam pipe 20, is inserted into the inflow space 9 of the hood 8.

The steam headers 24 include a first steam header 24A (24), a second steam header 24B (24), and a third steam header 24C (24). The first steam header 24A connects a first section 25 of the steam pipe 20 located within the hood 8 to the first steam nozzle 4A. The second steam header 24B connects a second section 27 located between the other end 23 of the steam pipe 20 and the first section 25 to the second steam nozzle 4B. The third steam header 24C connects the other end 23 of the steam pipe 20 to the third steam nozzle 4C. In other words, steam S to be supplied to each of the first steam nozzle 4A, second steam nozzle 4B, and third steam nozzle 4C is extracted from a single steam pipe 20.

In the second embodiment, as illustrated in FIG. 2, the hood 8 has a suction port 30 for sucking in steam S flowing out from each of the multiple steam boxes 6. In the embodiment illustrated in FIG. 2, the suction port 30 is formed by penetrating the top plate portion 15 of the hood 8. This suction port 30 is located downstream of the third steam box 6C (the most downstream steam box) in the conveying direction D1.

In the second embodiment, the suction port 30 is formed in the top plate portion 15 of the hood 8, but the present disclosure is not limited to this configuration. In some embodiments, the suction port 30 is formed in any of the front plate portion 12, rear plate portion 14, one side plate portion 16, and the other side plate portion 18 of the hood 8. In some embodiments, the suction port 30 is located upstream of the most downstream steam box in the conveying direction D1.

In the embodiment illustrated in FIG. 2, the gypsum recovery apparatus 1 further includes a steam exhaust pipe 32 that communicates with the suction port 30 of the hood 8. The exhaust port of the steam exhaust pipe 32 communicates, for example, with the outside of the building in which the gypsum recovery apparatus 1 is located. Although not shown, in some embodiments, the gypsum recovery apparatus 1 includes a suction device that is provided on the steam exhaust pipe 32 and generates a suction force that sucks the inlet space 9 of the hood 8. The suction device is, for example, a blower fan that blows gas outside the hood 8.

As illustrated in FIG. 2, in the second embodiment, the gypsum recovery device 1 is provided downstream of the third steam box 6C (the most downstream steam box) in the conveying direction D1 and further includes a curtain 34 that hangs down to guide the steam S flowing out of each of the first steam box 6A, second steam box 6B, and third steam box 6C to the top plate portion 15.

The curtain 34 is positioned within the inflow space 9 of the hood 8, upstream of the suction port 30 in the conveying direction D1. The curtain 34 hangs down from above the third steam box 6C. The lower end 35 of the curtain 34 is located below the lower end 39 of the rear wall portion 38 of the third steam box 6C. The curtain 34 is supported by a support rod 36 connected to at least one of the one side plate portion 16 and the other side plate portion 18. A gap is formed between the support rod 36 and the top plate portion 15 to allow steam S to pass through.

In the second embodiment, the curtain 34 is positioned upstream of the suction port 30 in the conveying direction D1, but the present disclosure is not limited to this configuration. In some embodiments, the curtain 34 is positioned so that the position of the curtain 34 and the position of the suction port 30 in the conveying direction D1 overlap each other. In some embodiments, the curtain 34 is attached to the rear panel portion 14 so as to be positioned within the hood 8.

(Actions and Effects)
2 , the plurality of steam boxes 6 are covered by one hood 8. Therefore, it is not necessary to prepare the same number of hoods 8 as the number of steam boxes 6, or two or more hoods 8, and therefore the manufacturing cost of the gypsum recovery device 1 can be reduced.

According to the second embodiment, the gypsum recovery device 1 includes multiple steam boxes 6, so more steam S can be supplied to the steam nozzle 4 than when a single steam box 6 is included, making it easier to heat the gypsum slurry X1 to a temperature suitable for dehydration. This improves the dehydration performance of the gypsum recovery device 1.

The gypsum recovery apparatus 1 is often designed so that the width dimension of the conveyor belt 50 is a predetermined size (e.g., 2 m). Therefore, if steam boxes 6 are arranged in a line along the width direction of the conveyor belt 50, the number of steam boxes 6 that can be arranged is limited. According to the second embodiment, as illustrated in FIG. 2, multiple steam boxes 6 are arranged along the conveying direction D1, so the number of steam boxes 6 provided in the gypsum recovery apparatus 1 can be increased.

According to the second embodiment, as illustrated in FIG. 2, an inlet port 30 is formed in the top plate portion 15 of the hood 8. Therefore, steam S flowing out from each of the first steam box 6A, second steam box 6B, and third steam box 6C is sucked into the inlet port 30, thereby preventing this steam S from leaking outside the hood 8.

The steam S flowing out from each of the multiple steam boxes 6 often flows along the conveying direction D1. According to the second embodiment, the suction port 30 is positioned downstream in the conveying direction D1 from the third steam box 6C (the most downstream steam box), allowing the steam S flowing out from each of the first steam box 6A, second steam box 6B, and third steam box 6C to be smoothly sucked into the suction port 30.

According to the second embodiment, as illustrated in FIG. 2, the suction port 30 is formed in the top plate portion 15, and the curtain 34 guides the steam S flowing out from each of the multiple steam boxes 6 to the top plate portion 15. As a result, the steam S flowing out from each of the multiple steam boxes 6 is sucked into the suction port 30, preventing the steam S from leaking outside the hood 8. In particular, the curtain 34 causes the steam S to flow upward, preventing the steam S from leaking out through gaps formed below the hood 8.

The contents described in each of the above embodiments can be understood, for example, as follows:

[1] A gypsum recovery apparatus (1) according to the present disclosure is a gypsum recovery apparatus for dehydrating a gypsum slurry (X1) to recover gypsum (X2),
a conveying device (2) configured to convey the gypsum slurry on a filter cloth (10);
a steam nozzle (4) disposed above the filter cloth for spraying steam (S) onto the gypsum slurry being transported by the transport device;
At least one steam box (6) configured to cover the steam nozzle and its surrounding space (7);
a hood (8) configured to cover the at least one steam box.

According to the configuration described in [1] above, the steam nozzle is covered by the steam box, and the steam box is covered by the hood, preventing steam from leaking outside the hood. This allows the steam sprayed from the steam nozzle to remain within the steam box, accelerating the temperature rise of the gypsum slurry. This makes it possible to provide a gypsum recovery device that can improve dehydration performance.

[2] In some embodiments, in the configuration described in [1] above,
the at least one steam box comprises a plurality of steam boxes (6A, 6B, 6C);
The hood was configured to cover each of the plurality of steam boxes.

The configuration described in [2] above eliminates the need to prepare multiple hoods corresponding to the number of steam boxes, thereby reducing the manufacturing costs of the gypsum recovery device.

[3] In some embodiments, in the configuration described in [2] above,
The plurality of steam boxes include a first steam box (6A) and a second steam box (6B) disposed downstream of the first steam box in the conveying direction of the gypsum slurry.

Gypsum recovery devices are often designed so that the width of the conveyor belt is a predetermined size. Therefore, if steam boxes are arranged in a line along the width of the conveyor belt, the number of steam boxes that can be arranged is limited. According to the configuration described in [3] above, multiple steam boxes 6 are arranged along the conveyance direction, allowing for a larger number of steam boxes to be included in the gypsum recovery device.

[4] In some embodiments, in the configuration described in [2] or [3] above,
The hood has an intake port (30) for drawing in the steam exiting each of the plurality of steam boxes.

According to the configuration described in [4] above, steam flowing out of each of the multiple steam boxes is sucked into the suction port, preventing this steam from leaking outside the hood.

[5] In some embodiments, in the configuration described in [4] above,
The plurality of steam boxes includes a most downstream steam box (6C) arranged on the most downstream side in the conveying direction (D1) of the gypsum slurry among the plurality of steam boxes,
The suction port is located downstream of the most downstream steam box in the conveying direction.

The steam flowing out from each of the multiple steam boxes often flows along the conveying direction. According to the configuration described in [5] above, by positioning the suction port downstream of the most downstream steam box in the conveying direction, the steam flowing out from each of the multiple steam boxes can be smoothly sucked into the suction port.

[6] In some embodiments, in the configuration described in [5] above,
The hood includes a front plate portion (12) extending along a vertical direction (D3), a rear plate portion (14) located downstream of the front plate portion in the conveying direction and extending along the vertical direction, and a top plate portion (15) connecting an upper end portion (13) of the front plate portion and an upper end portion (17) of the rear plate portion,
The suction port is formed in the top plate portion,
The steam conveying device further includes a curtain (34) that is provided downstream of the most downstream steam box in the conveying direction and hangs down so as to guide the steam flowing out from each of the plurality of steam boxes to the top plate portion.

According to the configuration described in [6] above, the suction port is formed in the top plate, and the curtain directs steam flowing out of each of the multiple steam boxes to the top plate. Therefore, steam flowing out of each of the multiple steam boxes is sucked into the suction port, preventing the steam from leaking outside the hood.

[7] In some embodiments, in the configuration according to any one of [1] to [6] above,
The method further includes a notch forming device (70) capable of forming a notch on the surface of the gypsum slurry being transported by the transport device,
The notch forming device is disposed upstream of the hood in the conveying direction of the gypsum slurry.

According to the configuration described in [7] above, the gypsum slurry is heated by steam after the surface film is destroyed, thereby improving dewatering performance.

1 Gypsum recovery device 2 Conveyor device 4 Steam nozzle 6 Steam box 6A First steam box 6B Second steam box 6C Third steam box (most downstream steam box)
7 Steam spray space 8 Hood 10 Filter cloth 12 Front plate portion 13 Upper end portion of front plate portion 14 Rear plate portion 15 Top plate portion 17 Upper end portion of rear plate portion 30 Suction port 34 Curtain 70 Notch forming device

D1 Conveying direction D2 Cross direction D3 Up-down direction S Steam X1 Gypsum slurry X2 Gypsum

Claims (7)

A gypsum recovery device for dewatering a gypsum slurry and recovering gypsum,
A conveying device configured to convey the gypsum slurry on a filter cloth;
a steam nozzle disposed above the filter cloth for spraying steam onto the gypsum slurry being transported by the transport device;
at least one steam box configured to cover the steam nozzle and a space around it;
a hood configured to cover the at least one steam box. the at least one steam box includes a plurality of steam boxes;
The hood is configured to collectively cover the plurality of steam boxes.
The gypsum recovery device according to claim 1. The plurality of steam boxes include a first steam box and a second steam box arranged downstream of the first steam box in a conveying direction of the gypsum slurry.
The gypsum recovery device according to claim 2. The hood has an intake port for sucking the steam flowing out from each of the plurality of steam boxes.
The gypsum recovery device according to claim 2 or 3. The plurality of steam boxes includes a most downstream steam box arranged on the most downstream side in a conveying direction of the gypsum slurry among the plurality of steam boxes,
The suction port is located downstream of the most downstream steam box in the conveying direction.
The gypsum recovery device according to claim 4. the hood includes a front plate portion extending along the up-down direction, a rear plate portion located downstream of the front plate portion in the conveying direction and extending along the up-down direction, and a top plate portion connecting an upper end portion of the front plate portion and an upper end portion of the rear plate portion,
The suction port is formed in the top plate portion,
The steam conveying device further includes a curtain that is provided downstream of the most downstream steam box in the conveying direction and hangs down so as to guide the steam flowing out from each of the plurality of steam boxes to the top plate portion.
The gypsum recovery device according to claim 5. The gypsum slurry conveying device further includes a notch forming device capable of forming a notch on a surface of the gypsum slurry being conveyed by the conveying device,
The notch forming device is arranged upstream of the hood in the conveying direction of the gypsum slurry.
The gypsum recovery device according to any one of claims 1 to 6.