JP5412042B2 - Foam recovery device and foam recovery system - Google Patents

Description

  The present invention relates to wastewater treatment of flue gas desulfurization equipment applied to power plants such as coal-fired, crude oil-fired, and heavy oil-fired, and in particular, removes bubbles from the wastewater of flue gas desulfurization equipment that desulfurizes using the seawater method. The present invention relates to a foam recovery apparatus and a foam recovery system.

Conventionally, in a power plant using coal, crude oil or the like as fuel, combustion exhaust gas (hereinafter referred to as “boiler exhaust gas”) discharged from the boiler is sulfur dioxide (SO ₂ ) or the like contained in the boiler exhaust gas. Sulfur oxide (SOx) is removed before being released to the atmosphere. As a desulfurization method of the flue gas desulfurization apparatus that performs such a desulfurization treatment, a limestone gypsum method, a spray dryer method, and a seawater method are known.

Among these, the flue gas desulfurization apparatus (hereinafter referred to as “seawater desulfurization apparatus”) employing the seawater method is a desulfurization system that uses seawater as an absorbent. In this system, for example, by supplying seawater and boiler exhaust gas into a desulfurization tower (absorption tower) having a cylindrical shape such as a substantially cylindrical shape, a wet-based gas-liquid contact is generated using seawater as an absorption liquid. To remove sulfur oxides.
When the desulfurized seawater (spent seawater) used as an absorbent in the desulfurization tower described above is drained by flowing through the water channel (Seawater Oxidation Treatment System; SOTS) 1, for example, as shown in FIG. 1 is decarboxylated (explosion) by aeration that causes fine aeration bubbles 3 to flow out from an aeration nozzle 2 installed on the bottom surface of 1.

When the pH value is adjusted by the above-described decarboxylation, fine aeration bubbles 3, components in boiler exhaust gas taken up into seawater in the desulfurization tower (dust etc.), organic matter contained in seawater, etc. Due to this interaction, a large amount of bubbles 4 are generated on the surface of the used seawater flowing in the water channel 1. Since the bubbles 4 not only disappear easily but also contain harmful substances, it is not preferable in view of the landscape and environmental pollution to be released from the water channel 1 to the surrounding sea area together with seawater.
Thus, the area | region of the water channel 1 which performs the aeration which flows out the fine aeration bubble 3 and decarboxylates used seawater is called the aeration area 5.

As a conventional technique similar to or related to the removal of bubbles on the water surface, an oil recovery apparatus for recovering oil floating on the water surface is known. The oil recovery apparatus includes a levitation unit that floats on the water surface and supports the oil recovery device, an oil suction unit, and an oil collection unit that collects oil from an oil collection port and guides the oil to the suction unit. (For example, see Patent Document 1)
In addition, as a device that can smoothly collect paint sludge and the like floating in the collection tank, a collection device such as sludge has been proposed. (For example, see Patent Document 2)
Japanese Patent Laying-Open No. 2004-351279 (see FIG. 1 and the like) JP-A-6-296911 (see FIG. 1 and the like)

By the way, in the used seawater after desulfurization flowing through the water channel 1 and draining to the surrounding sea area, the bubbles 4 floating on the water surface cause deterioration of the landscape and environmental pollution. For this reason, in order to eliminate such a problem, the apparatus for isolate | separating and removing the foam | bubble 4 on the water surface appropriately from seawater is needed. That is, the foam recovery apparatus which appropriately separated and removed the bubbles 4 floating on the used seawater surface after desulfurization and recovered the wastewater without bubbles 4 to the surrounding sea area and the foam Development of a foam recovery system equipped with a recovery device is desired.
This invention is made | formed in view of said situation, The place made into the objective collect | recovers the bubbles floating on the used seawater surface after desulfurization, and uses only the used seawater from which the foam was removed. An object of the present invention is to provide a foam recovery device that can drain water into the surrounding sea area and a foam recovery system including the foam recovery device.

In order to solve the above problems, the present invention employs the following means.
The foam recovery apparatus according to claim 1 is installed in a water channel for flowing and draining used seawater discharged from a desulfurization tower of a flue gas desulfurization apparatus that uses seawater as an absorbent, and floats on the surface of the used seawater. A foam recovery apparatus for removing and recovering foam, wherein the cross-sectional area of the water channel is narrowed and connected via an overflow weir formed on a side surface inclined to intersect the flow of the used seawater A foam collecting pit is provided, and a foam floating body that is held floating so as to cross the water channel is installed to separate the bubbles floating on the water surface and the surface seawater flow from the main stream of the used seawater. The foam collecting pit has a water surface portion and an underwater portion, and an inclined surface that obliquely crosses the water channel is formed on the upstream side in the flow direction of the used seawater. It is characterized by this.

According to such a foam recovery device, there is a foam recovery pit portion connected via an overflow weir formed on the side surface of the inclined surface intersecting the flow of the used seawater by narrowing the cross-sectional area of the water channel. A foam floating body that is installed and held in a floating state across the water channel is installed, and the bubbles floating on the water surface and the surface seawater flow are separated from the mainstream of the used seawater and led to the foam recovery pit section. The bubble floating body has a water surface portion and an underwater portion, and an inclined surface that obliquely crosses the water channel is formed on the upstream side in the flow direction of the used seawater. The installation position (height) changes following the fluctuation of the level of the used seawater flowing through. For this reason, the foam floating body is always held at substantially the same position on the water surface and can block the upper part of the used seawater. Therefore, the bubbles floating on the water surface and the surface seawater flow are lower than the channel side wall and the foam floating body. It is separated from the main stream of used seawater through the overflow weir on the side of the waterway and is reliably recovered in the foam recovery pit.
In this case, the overflow weir is formed on the side surface with the inclined surface intersecting the flow of the used seawater by narrowing the channel cross-sectional area of the water channel, so that the flow of taking bubbles into the overflow weir can be made smooth .

  In the above invention, it is preferable to provide a return flow path that connects between the foam recovery pit portion and the water channel, and separates at least a part of the recovered seawater from the foam and returns the water channel to the water channel. A suction conveyance device such as a pump required for the subsequent process of the foam recovery pit can be reduced in size.

  In the above invention, it is preferable that the overflow weir is provided with a variable weir height mechanism, whereby the height of the overflow weir is optimized according to the thickness of the foam, etc. Can be increased.

Next, a foam recovery device as a reference example is installed in a water channel for flowing and draining used seawater discharged from a desulfurization tower of a flue gas desulfurization device that uses seawater as an absorbent, and on the surface of the used seawater. A bubble recovery device that removes and recovers floating bubbles, and blocks a flow path from underwater to a predetermined position on the water surface, leaving a bubble recovery pit portion adjacent to the water channel and a water channel bottom side. The foam holding member installed across the water channel, and the foam recovery means for recovering the foam blocked by the foam holding member from the water surface to the foam recovery pit part, The recovery means includes a moving part that can reciprocate across the water channel, and a scraper that is suspended from the moving part so as to move up and down. An inclined wall that rises to the recovery pit It is characterized in that that example.

According to such a foam recovery device, the foam recovery pit portion provided adjacent to the water channel and the water channel bottom side are left across the water channel so as to block the flow path from the water to a predetermined position on the water surface. It comprises a foam holding member installed and a foam recovery means for recovering the foam blocked by the foam holding member from the water surface to the foam recovery pit , and the foam recovery means reciprocates across the water channel. A movable portion that is movable, and a scraper that is suspended from the movable portion so as to be movable up and down, and the foam recovery means includes an inclined wall surface that rises from the side wall portion of the water channel to the foam recovery pit portion. The foam that floats and flows upward is blocked by the foam holding member, and the accumulated foam can be reliably collected in the foam collection pit section by the foam collection means.

In the above reference example , it is preferable that the foam recovery means includes a moving part that can reciprocate across the water channel, and a scraper suspended from the moving part. The bubbles floating on the surface can be transported so as to be scraped off by a scraper that moves together with the moving part, and recovered in the foam recovery pit part.
In this case, by using the inclined wall surface from the side wall of the water channel to the foam recovery pit part, the foam can be separated and recovered from the used seawater.

In addition, a foam recovery device as a reference example is installed in a water channel that drains the used seawater discharged from the desulfurization tower of the flue gas desulfurization device that uses seawater as an absorbent, and floats on the surface of the used seawater. A foam recovery device that removes and recovers bubbles to block the flow path from underwater to a predetermined position on the water surface, leaving the foam recovery pit portion provided adjacent to the water channel and the water channel bottom side A foam retaining member installed across the water channel, and a foam recovery means for recovering the foam blocked by the foam retaining member from the water surface to the foam recovery pit section, the foam recovery The means is a rotary scraper that rotates on an arc wall that rises from a side wall portion of the water channel to the bubble recovery pit portion.
According to such a foam recovery device, since the foam recovery means is a rotary scraper that rotates on an arc wall that rises from the side wall portion of the water channel to the foam recovery pit portion, the foam that floats and accumulates on the water surface, The rotating scraper can be scraped off and transported to the foam recovery pit. At this time, since the arc wall is provided, the rotation of the rotary scraper is not hindered, and the bubbles can be separated and recovered from the used seawater.
In this case, it is preferable that the rotary scraper is rotationally driven by the hydraulic power of the used seawater flowing through the water channel, whereby the rotary scraper can save energy.

In addition, a foam recovery device as a reference example is installed in a water channel that drains the used seawater discharged from the desulfurization tower of the flue gas desulfurization device that uses seawater as an absorbent, and floats on the surface of the used seawater. A foam recovery device that removes and recovers bubbles to block the flow path from underwater to a predetermined position on the water surface, leaving the foam recovery pit portion provided adjacent to the water channel and the water channel bottom side A foam retaining member installed across the water channel, and a foam recovery means for recovering the foam blocked by the foam retaining member from the water surface to the foam recovery pit section, the foam recovery The means is an ejector that sucks bubbles from the suction port floating on the water surface and collects the bubbles to the bubble collection pit portion.
According to such a foam recovery device, since the foam recovery means is an ejector that sucks the foam from the suction port floating on the water surface and recovers it to the foam recovery pit part, the foam floating on the water surface is separated from the used seawater. Can be recovered.

In addition, a foam recovery device as a reference example is installed in a water channel that drains the used seawater discharged from the desulfurization tower of the flue gas desulfurization device that uses seawater as an absorbent, and floats on the surface of the used seawater. A foam recovery device that removes and recovers bubbles to block the flow path from underwater to a predetermined position on the water surface, leaving the foam recovery pit portion provided adjacent to the water channel and the water channel bottom side A foam retaining member installed across the water channel, and a foam recovery means for recovering the foam blocked by the foam retaining member from the water surface to the foam recovery pit section, the foam recovery The means is a mesh belt conveyor provided with a squeezing roller above the bubble recovery pit portion.
According to such a foam recovery device, since the foam recovery means is a mesh belt conveyor provided with a squeezing roller above the foam recovery pit section, the foam floating on the water surface is separated from the used seawater and recovered. can do.

The foam recovery system according to the present invention is installed in a water channel for flowing and draining used seawater discharged from a desulfurization tower of a flue gas desulfurization apparatus that uses seawater as an absorbent, and the foam floating on the surface of the used seawater. It is a foam recovery system provided with the foam recovery apparatus which isolate | separates and removes, It is the foam recovery apparatus in any one of Claim 1 to 3 , The foam which dehydrates and dries the foam collect | recovered with the said foam recovery apparatus The apparatus comprises a processing device and a suction conveyance device that sucks the bubbles collected in the bubble collection pit and conveys the bubbles to the bubble treatment device via a flow path.

According to such a foam recovery system, the foam recovery apparatus according to any one of claims 1 to 3 , the foam treatment apparatus for dehydrating and drying the foam recovered by the foam recovery apparatus, and the foam recovered in the foam recovery pit And a suction transfer device that transports the air to the foam treatment device through the flow path, so that the foam floating body of the foam recovery device follows the fluctuation in the water level of the used seawater flowing in the water channel by buoyancy. As a result, the installation position (height) changes. For this reason, the foam floating body is always held at substantially the same position on the water surface and can block the upper part of the used seawater. Therefore, the bubbles floating on the water surface and the surface seawater flow are lower than the channel side wall and the foam floating body. It is separated from the main stream of used seawater through the overflow weir on the side of the waterway and is reliably recovered in the foam recovery pit. The foam recovered in the foam recovery pit portion is transported to the foam processing apparatus by the suction transport apparatus, and then dehydrated and dried to be separated into the foam component and the seawater component.

  According to the present invention described above, bubbles are appropriately separated and removed from the surface of the used seawater drained from the desulfurization tower and then drained through the water channel, and only the used seawater without bubbles is collected in the surrounding sea area. Since the water can be drained, the problem that the bubbles floating on the water surface deteriorate the landscape and the problem of environmental pollution can be solved.

Hereinafter, one embodiment of a foam recovery device and a foam recovery system concerning the present invention is described based on a drawing.
<Reference configuration example>
The foam recovery system 10 shown in FIGS. 1 to 3 is aerated after passing through aeration area 5 discharged from a desulfurization tower (not shown) of a flue gas desulfurization apparatus that uses seawater as an absorbent, for example. The foam recovery device 20 that separates and recovers the bubbles 4 floating on the water surface WL of the used seawater by being installed in a water channel (SOTS) 1 for flowing and draining the used seawater as I have. The foam recovery apparatus 20 includes a foam recovery pit 40 connected via an overflow weir 30 formed on the side surface of the water channel 1 and a foam floating body 50 held in a floating state so as to cross the water channel 1. The foam collecting body 50 separates the bubbles 4 and the surface seawater flow floating on the water surface WL from the main stream of the used seawater, and the foam recovery pit section 40 passes through the overflow weir 30 as indicated by an arrow Fb in the figure. Configured to lead to.

The overflow weir 30 is a region set lower than the water surface WL so that the side wall 1a of the water channel 1 is partially cut away. A bubble recovery pit section 40 is provided adjacent to the overflow weir 30, that is, on the side wall 1 a which is the side surface of the water channel 1 where the overflow weir 30 is provided, so as to be adjacent to the water path 1. ing.
Moreover, about the overflow dam 30 mentioned above, in order to be able to optimize the height according to the thickness etc. of a bubble, it is preferable to provide the variable mechanism of the dam height mentioned later.

  The foam recovery pit unit 40 is a space connected to the water channel 1 through the overflow weir 30. The bottom surface 41 of the foam recovery pit portion 40 is set at a position lower than the overflow weir 30. Since the periphery of the bottom surface 41 is surrounded by the side wall 42, the foam recovery pit portion 40 can store the foam 4 separated from the main stream of the used seawater through the overflow dam 30 and a part of the used seawater. it can. In this case, a part of the used seawater separated from the mainstream of the used seawater is a surface seawater flow guided to the overflow weir 30 side by the foaming float 50 described later. The volume of the foam recovery pit unit 40 is determined in consideration of various conditions such as the capacity of the suction conveyance device 12 described later and the amount of used seawater.

  Moreover, it is preferable to provide the bubble collection pit part 40 with the return flow path 43 which connects between the water paths 1. The return flow path 43 is, for example, a pipe line connected to an appropriate position of the water channel 1 from the bottom surface 41 or a position near the bottom surface 41, and has a processing capacity of a post-process (a suction conveyance device 12 or the like) in a later-described foam recovery pit section 40. The purpose is to return at least a part of the surface seawater flow collected in the foam collection pit section 40 to the water channel 1 in order to reduce the amount. That is, in the above-described foam recovery pit section 40, it is desirable to reliably separate the recovered foam 4 from the surface seawater flow and return only the surface seawater flow to the water channel 1 to reduce the amount of subsequent processing.

  Therefore, in order to prevent the bubbles 4 floating on the water surface from flowing into the return flow path 43, it is desirable to install appropriate bubble separation means in the bubble recovery pit section 40. In addition, as a specific example of the bubble separating means, for example, there is a partition plate (not shown) attached so as to surround the inlet opening 44 in the vicinity of the return flow path 43, and this partition plate is an upper portion where the bubbles 4 are floating. In addition, the bubble 4 can be reliably separated from the seawater flowing out through the inlet opening 44 because the communication channel for flowing seawater is provided on the bottom surface 41 side of the lower portion.

The bubble floating body 50 is a floating body having a width dimension substantially the same as the width W of the water channel 1, and floats on the water surface WL so as to cross the water channel 1, that is, to block the upper part of the water channel 1. Is held by. The foam floating body 50 is installed so as to guide the foam 4 and the surface seawater flow from the overflow weir 30 to the foam recovery pit 40 out of the foam 4 and the used seawater flowing in the water channel 1.
The illustrated bubble floating body 50 is a floating body having a substantially trapezoidal shape in plan view, and has an inclined surface 51 that obliquely crosses the water channel 1 on the upstream side in the flow direction of the used seawater (arrow F in the figure). Is formed. The inclined surface 51 is inclined so that the side wall 1a side where the overflow weir 30 is provided is downstream from the opposite side wall 1b side.

Further, the height (thickness) H of the bubble floating body 50 is such that when it floats on the water surface WL, the water portion having an appropriate height h1 protruding above the water surface and the water having an appropriate height h2 submerged in the water. And have a part. In other words, the foam floating body 50 guides the flow of the foam 4 in which the surface portion of the height h1 floats on the water surface WL to the foam recovery pit 40, and the underwater portion of the height h2 foams the surface seawater flow of the used seawater. It is configured to lead to the collection pit 40. In addition, although the height h1 of the above-mentioned water part should just be determined according to the condition of the bubble 4 which floats on water, etc., it should just be made into the height comparable as the upper end of the side walls 1a and 1b, for example.
Such a bubble floating body 50 is fixed in a state in which it is allowed to move in the vertical direction by buoyancy in order to prevent it from flowing from a predetermined position in the water channel 1 to the water flow. In other words, the floating floating body 50 having a floating structure can be moved in the vertical direction according to the fluctuation of the water level in the water channel 1 but is supported at a predetermined position so as not to move in the flow direction of the used seawater flowing in the water channel 1. Has been.

By the way, the above-mentioned foam floating body 50 is not limited to the trapezoidal (plan view) side as shown in FIG. 2 and the inclined surface 51 is used, and various modifications are possible.
In the first modification shown in FIGS. 4 and 5, the inclined surface 51 is formed by arranging the bubble floating body 50 </ b> A having a substantially parallelogram shape in the water channel 1.
Further, in the second modification shown in FIG. 6, the bubbles 4 and the surface seawater flow are guided to the bubble recovery pit 40 by the curved surface 52 formed by the bubble floating body 50 </ b> B instead of the linear inclined surface 51. Good.

  As such a bubble floating body 50, a floating body having a hollow structure or the like that matches the size and shape of the water channel 1 may be employed, or a commercially available oil fence that is advantageous in terms of cost may be employed. In addition, it is desirable for the oil fence to be equipped with a tide level-adaptive slurder that can cope with fluctuations in water surface.

  The foam recovery system 10 includes a transport channel formed by a pipe 11 having a tip disposed in the foam recovery pit 40 in order to transport and process the recovered foam 4 in the foam recovery pit 40 having the above-described configuration. Yes. A suction conveyance device 12 is connected to the other end side of the pipe 11 forming the conveyance flow path, and a foam treatment device 13 is provided on the discharge side of the suction conveyance device 12.

For example, a pump such as an ejector pump or a vacuum pump is used for the suction conveyance device 12 described above.
Moreover, the centrifuge etc. which dehydrate-process the collect | recovered foam 4 and isolate | separate into a foam component and seawater are used for the foam processing apparatus 13. FIG. The seawater separated here is drained back to the surrounding sea area, and the foam component is dried to be a solid matter. This solid material is reused or buried in the facility.
That is, the foam collection system 10 sucks the bubbles 4 collected from the foam collection pit 40 and conveys them to the foam treatment device 13 in addition to the foam floating body 50 having a floating structure (water facility) disposed on the water channel 1. It is comprised by the land equipment provided with the suction conveyance apparatus 12 and the foam processing apparatus 13 which carries out the dehydration drying of the foam 4 collect | recovered by the foam collection | recovery pit 40. FIG.

Hereinafter, the effect | action is demonstrated with the foam collection | recovery process procedure about the foam collection system 10 of the structure mentioned above.
The used seawater after desulfurization drained from the desulfurization tower flows through the water channel 1 in the direction of arrow F. Bubbles 4 are floating on the surface of the used seawater flowing through the water channel 1, and when the bubbles 4 reach the bubble floating body 50, the bubbles 4 and the surface seawater flow are used to flow the used seawater. Separate from. At this time, since the bubble floating body 50 has a floating body structure, the positional relationship with the used seawater surface is maintained substantially constant regardless of the water surface fluctuation.

As a result, the surface seawater flow that flows above the bubbles 4 and the used seawater on the water surface is guided to the inclined surface 51 and separated from the mainstream of the used seawater, and falls into the foam recovery pit 40 and is recovered. On the other hand, the main stream of used seawater flows below the inclined surface 51 except for the surface seawater flow that flows above the bubbles 4 and the used seawater.
The bubbles 4 collected in the bubble collection pit 40 are sucked by operating the suction conveyance device 12 and conveyed to the bubble treatment device 13 through the pipe 11.

The foam 4 thus transported to the foam treatment device 13 is further separated into seawater and foam components as necessary. The separated seawater is drained to the surrounding sea area without the bubbles 4. On the other hand, the foam component after separation becomes a solid substance by a drying process, and is reused in a facility or embedded in an appropriate place.
Accordingly, the bubbles 4 can be appropriately separated and removed from the surface of the used seawater discharged after flowing through the water channel 1 after being drained from the desulfurization tower, and only the used seawater without bubbles 4 can be drained to the surrounding sea area. As a result, the problem that the bubbles 4 floating on the water surface deteriorate the landscape and the problem of environmental pollution can be solved.

  By the way, the foam floating body 50, the foam recovery pit 40, and the foam recovery system 10 described above may be provided for each desulfurization tower that drains used seawater, or used seawater drained from a plurality of desulfurization towers. It may be provided at a position where it is merged into one water channel 1.

<First Embodiment>
Subsequently, the bubble recovery apparatus of the present invention will be described with reference to the first embodiment in the drawings. In addition, the same code | symbol is attached | subjected to the part similar to the structural example mentioned above, and the detailed description is abbreviate | omitted.
In the foam recovery apparatus 20A shown in FIGS. 7 and 8, a plurality of aeration areas 5 arranged on the upstream side are provided. In the illustrated configuration example, three rows of aeration areas 5A, 5B, and 5C arranged in parallel are provided. The aeration area 5 in this case enables continuous operation using the remaining two rows, for example, by sequentially maintaining one of the three rows. In addition, about the arrangement number of the aeration area 5, it is not limited to 3 rows mentioned above.

In this embodiment, an inexpensive oil fence 50C is employed as the foam floating body. The oil fence 50C is preferably provided with a slurder (not shown) that can cope with sea level tide level fluctuations.
In this embodiment, a dewatering tank 45 and a coagulation tank 46 are provided connected to the downstream side of the foam recovery pit 40. The foam guided to the oil fence 50C and collected in the foam recovery pit 40 together with the used seawater through the overflow weir 30 operates a float pump (not shown) disposed on the water surface in the foam recovery pit 40, for example. As a result, water can be drained from the foam recovery pit 40 to the dewatering tank 45. In the dewatering tank 45, the foam is separated from the used seawater and sent to the aggregation tank 46. The used seawater that has flowed into the foam recovery pit 40 is returned to the water channel 1 through a return channel 43 provided near the bottom.

  Furthermore, in this embodiment, the overflow weir 30 is provided on the inclined surface 1 c formed by narrowing the flow path cross-sectional area of the water channel 1. For this reason, since the overflow weir 30 is provided on the inclined surface 1c intersecting with the flow direction, the curved surface formed by the oil fence 50C is compared with the case where it is provided on the side wall 1a parallel to the flow direction. In cooperation, the flow of collecting the foam into the foam collection pit 40 is made smooth.

By the way, in the embodiment shown in FIGS. 7 and 8, the overflow weir 30 is provided in a part of the inclined surface 1c. For example, in the foam recovery apparatus 20A ′ of the modified example shown in FIG. An inclined surface 1c is provided over the entire area 1c. If such a structure of the overflow weir 30 is adopted, it becomes possible to recover more smoothly and efficiently.
In this modification, the return flow path 43 is not provided, but the return flow path 43 may be provided as necessary.

In addition, the overflow weir 30 described above is provided with a variable weir height mechanism so that the weir height can be adjusted according to foam thickness, water surface fluctuation, etc., as shown in FIGS. 10 to 12, for example. It is preferable. In addition, FIG. 10 is the figure which looked at the overflow weir 30 provided in the side wall 1a of the water channel 1 from the foam collection | recovery pit part 40 side.
In the illustrated configuration example, a gate board 31 is installed on the overflow weir 30. As shown in the plan view of FIG. 12, the gate board 31 is supported by guides 32 at both side ends and is slidable in the vertical direction, and a rod 33 whose height (length) can be adjusted at the upper end. Float 34 is attached through.

In this case, the rod 33 is, for example, a bolt that is screwed into a female screw portion formed on the gate board 31, and the float height can be adjusted by changing the insertion amount (screwing length). That is, the distance from the upper end of the gate board 31 that defines the height of the overflow weir 30 to the float 34 that floats on the water surface can be adjusted. Further, reference numeral 35 in the drawing denotes a seal packing attached in the vicinity of both side ends and the lower end portion of the gate board 31.
Note that the weir height variable mechanism is not limited to the above-described configuration example, and the gate board 31 may be mechanically moved up and down by a drive source such as an electric motor.

<Reference example>
Then, the reference example is demonstrated based on drawing about the foam collection | recovery apparatus of this invention. In addition, the same code | symbol is attached | subjected to the part similar to the structural example and embodiment mentioned above, and the detailed description is abbreviate | omitted.
The foam recovery apparatus 20B shown in FIG. 13 and FIG. 14 is installed in the water channel 1 for flowing and draining the used seawater discharged from the desulfurization tower of the flue gas desulfurization apparatus that uses seawater as an absorbent. It is a device that removes and collects bubbles floating on the surface. The foam recovery device 20B includes a foam recovery pit portion 40 provided adjacent to the water channel 1, a foam holding member 50D, and a scraper device 60 provided as foam recovery means.

The foam holding member 50D is installed across the water channel 1 while blocking the flow path from underwater to a predetermined position on the water surface, leaving the water channel bottom side of the water channel 1, for example, curtain wall, foam floating body And an oil fence is desirable. That is, the foam holding member 50 </ b> D blocks and holds bubbles floating on the surface of the used seawater flowing through the water channel 1, and the used seawater flows through the bottom side of the water channel 1.
The foam blocked by the foam holding member 50D accumulates in a state of floating on the water surface upstream of the foam holding member 50D. Therefore, a scraper device 60 is provided as a foam recovery means for recovering the foam to the foam recovery pit section 40. In the illustrated example, an apparatus for processing the foam collected in the foam collection pit unit 40 is not shown, but the configuration of the above-described embodiment may be adopted as appropriate.

Below, the structural example of the scraper apparatus 60 is demonstrated based on FIGS. 13-15.
The illustrated scraper device 60 includes a moving unit 61 that can reciprocate across the water channel 1 and a scraper 62 that is suspended from the moving unit 61 and moves up and down.
The moving unit 61 is a device that travels by being driven by an electric motor or the like on a pair of rails 63 provided across the upper part of the water channel 1. In the illustrated configuration example, a curtain wall 53 is employed for the foam holding member 50D, one of the rails 63 is laid on the upper surface of the curtain wall 53, and the other rail 63 is provided on a rib 64 provided across the water channel 1. However, it is not particularly limited, for example, a dedicated frame is provided on both rails 63.

  In the scraper device 60 configured in this manner, when the moving unit 61 travels on the rail 63 and reciprocates, the scraper 62 transports the bubbles floating on the surface of the water so that the scraper 62 scrapes off the bubbles. Collected in part 40. That is, when the moving unit 61 travels toward the foam recovery pit unit 40, the lower end of the scraper 62 is lowered to a position where it enters the water, so that the bubbles floating on the water surface can be reliably transmitted to the foam recovery pit unit 40. Can be conveyed. When the moving part 61 travels from the foam recovery pit part 40 toward the side wall 1b on the opposite side, the scraper 62 is brought up to a sufficient height from the water surface so as not to contact the foam. The

Next, a first modification of the above-described scraper device 60 will be described with reference to FIG. In this first modification, the scraper moving together with the moving part 61 transports the foam so as to scrape off the foam and collects it in the foam recovery pit part 40, and the upper end of the overflow weir 30 formed on the side wall 1a of the water channel 1 From the portion to the bubble recovery pit portion 40 is an inclined wall surface 65 with a gradually increasing wall surface.
Thus, if the inclined wall surface 65 rising from the side wall portion 1a of the water channel 1 to the bubble recovery pit portion 40 is formed, the moving portion 61 moves toward the bubble recovery pit portion 40 in the right direction in FIG. 15B. As the reference numeral 61 → 61a → 61b in the drawing is reached, the lower end of the scraper 62 is lifted to the inclined wall surface 65 and is inclined (see the reference 62a in the drawing). For this reason, when passing through the inclined wall surface 65, the foam is held by the scraper 62, and the used seawater freely falls by gravity, so that the foam can be separated and recovered from the used seawater. The burden on the post process can be reduced.

In this way, when the moving part 61 moves over the inclined wall surface part 65 and above the foam recovery pit part 40, the foam conveyed to the scraper 62b having an increased inclination angle falls into the pit and is recovered. Further, the scraper 62b is released from the inclined state when the lower end portion exceeds the inclined wall surface portion 65 and is directed downward (see reference numeral 62b 'in the drawing). Thereafter, the moving unit 61 pulls up the scraper 62 and moves to the side wall 1b side.
Note that the shape of the inclined wall surface portion 65 is set so that the highest bubble recovery pit portion 40 side is higher than the maximum water level of the used seawater flowing through the water channel 1 (for example, the water level at high tide).

  According to such a foam recovery device, the foam recovery pit portion provided adjacent to the water channel and the water channel bottom side are left across the water channel so as to block the flow path from the water to a predetermined position on the water surface. Since the foam holding member is provided and the foam collecting means for collecting the foam blocked by the foam holding member from the water surface to the foam recovery pit part, the foam floating member floats on the water surface and flows. The foam that has been dammed up and collected can be reliably recovered to the foam recovery pit by the foam recovery means.

Next, a second modification of the above-described scraper device 60 will be described with reference to FIG. In the second modification, a rotary scraper 67 that rotates on an arc wall 66 that rises from the side wall 1a of the water channel 1 to the bubble recovery pit 40 is employed.
The rotary scraper 67 is provided with a plurality of arm portions 70 radially provided from a rotating shaft 69 connected to a drive device 68 equipped with an electric motor, a speed reducer, etc., and a scraper 71 is attached to the tip of each arm portion 70. is there.

The arc wall 66 in this case is basically the same as the inclined wall surface 65 described above, but has a predetermined positional relationship with the scraper 71 that rotates and moves along the wall surface without disturbing the rotation of the rotary scraper 67. The shape can be maintained. In addition, about the scraper 71 in this case, it is preferable to attach a brush etc. to the front-end | tip part.
Therefore, when the rotary scraper 67 is operated, a flow is generated that draws bubbles held on the curtain wall 53 toward the arc wall 66 side. Then, the scraper 71 that rotates sequentially conveys the used seawater together with the foam to the foam recovery pit section 40, and the foam separated from the used seawater at the arc wall 66 falls into the foam recovery pit section 40 and is recovered. Is done. On the other hand, the used seawater separated from the bubbles is returned to the water channel 1 along the arc wall 66.

With such a configuration, the bubbles floating on the surface of the water can be conveyed so as to be scraped off by the rotating scraper 71 and collected in the bubble recovery pit section 40. At this time, since the arc wall 66 is provided, the rotation of the rotary scraper 67 is not hindered, and the bubbles can be separated and recovered from the used seawater.
Further, in the present reference example and its modification, the foam holding member 50D and the curtain wall 53 are installed so as to be orthogonal to the water channel 1. However, as in the third modification shown in FIG. A curtain wall 53 ′ inclined so as to be led to the flow weir 30 may be employed.
Further, in the present reference example and the modification thereof, the foam holding member 50D and the curtain wall 53 are installed so as to be orthogonal to the water channel 1. However, as in the fourth modification example shown in FIG. May be adopted.

Further, the rotary scraper 67 of the second modified example described above is rotationally driven by the hydraulic power of the used seawater flowing through the water channel 1 instead of a drive source such as an electric motor as in the fifth modified example shown in FIG. You may be made to do. That is, as shown in the illustrated rotary scraper 67 ', a water turbine 72 is installed in the water channel 1, and the water turbine 72 is rotated by the flow of used seawater to obtain the driving force of the rotary scraper 67', thereby saving energy. Also good.
Reference numeral 73 in the figure denotes a gear box that decelerates the rotational driving force of the water turbine 72 and transmits it to the rotary scraper 67 '.

<Reference example>
Then, the reference example is demonstrated based on drawing about the foam collection | recovery apparatus of this invention. In addition, the same code | symbol is attached | subjected to the part similar to embodiment mentioned above, and the detailed description is abbreviate | omitted.
A foam recovery device 20C shown in FIG. 20 is an ejector that sucks bubbles from the suction port 80 floating on the water surface and recovers them to the foam recovery pit section 40.

The suction port 80 floats with the suction opening 80a facing downward by the buoyancy received by the float 81 so as to maintain a predetermined distance from the water surface. In the illustrated configuration example, an arm 82 that extends radially from the suction port 80 is bent downward, and a float 81 is attached to the tip thereof. For this reason, the space | interval from the water surface to the inlet 80 is formed only for the bending part of the arm 82, and it has floated on the water surface in the stable state.
A pipe 83 such as a pipe or a hose is connected to the suction port 80 described above. The pipe 83 is connected to an ejector portion 84 provided in the bubble recovery pit portion 40.

The ejector portion 84 is a device that blows air from the blower 85 such as a compressor or a blower to the ejector pipe 86 and sucks bubbles by generating a negative pressure at the pipe outlet 83 a that opens in the ejector pipe 86. In the illustrated configuration example, the outlet 86 a of the ejector pipe 86 is installed so as to face downward in the bubble recovery pit portion 40, and a pipe 83 is concentrically installed on the downward part of the ejector pipe 86.
Accordingly, since the air blown from the blower 85 flows at high speed in the ejector pipe 86, negative pressure is generated at the pipe outlet 83a and the pipe 83, and bubbles below and around the suction port 80 are sucked. Then, it is collected in the bubble collection pit section 40 through the pipe 83. As a result, the foam 4 floating on the water surface can be separated from the used seawater and recovered in the foam recovery pit section 40.
Although not shown in the present reference example , a sensor for detecting the height of bubbles on the seawater surface may be installed, and the blower device 85 may be driven according to the state of bubble accumulation, thereby saving energy. it is possible to achieve the reduction.

<Reference example>
Then, the reference example is demonstrated based on drawing about the foam collection | recovery apparatus of this invention. In addition, the same code | symbol is attached | subjected to the part similar to embodiment mentioned above, and the detailed description is abbreviate | omitted.
A foam recovery device 20D shown in FIG. 21 is a conveyor device provided with a mesh belt 91 provided with a squeezing roller 90 above the foam recovery pit portion 40. This foam recovery apparatus 20D recovers the foam accumulated on the water surface by being dammed up by the foam floating body 50, the oil fence 50C, etc. of each embodiment described above.

  The mesh belt 91 is a fine mesh belt that passes used seawater. The conveyor device for rotating the mesh belt 91 clockwise includes a first roller 92 positioned substantially on the water surface, a second roller 93 disposed near the upper side of the side wall 1a constituting the water channel 1, and a foam recovery pit. A third roller 94 disposed above the portion 40, a guide roller 95 disposed below the second roller 92, and a drive mechanism (not shown) are provided. In this case, the first roller 92, the second roller 93, the second roller 93, and the second roller 93 to the third roller 94 are transported downward, and the first roller 92, the second roller 93, and the second roller 93 are transported downward. The height position of the third roller 94 is set. In addition, the code | symbol 96 in a figure is a seawater guide, and the auxiliary | assistant roller is installed between each roller as needed.

When the conveyor device having the above-described configuration is operated, the first roller 92 is substantially at the water surface position, and therefore the mesh belt 91 that travels upward through the first roller 92 collects and conveys bubbles floating on the water surface. To do. At this time, used seawater is also attached to the mesh belt 91 together with the foam, but this used seawater passes through the mesh belt 91 and falls onto the water channel 1 when transported toward the second roller 93. .
During the downward belt travel from the second roller 93 to the third roller 94, relatively large bubbles out of the bubbles adhering to the mesh belt 91 naturally fall into the bubble collection pit portion 40 and are collected. The Further, relatively small foam that cannot fall naturally is removed from the mesh belt 91 when passing through the squeezing roller 90, and dropped into the foam collection pit section 40 and collected.

Further, since the seawater guide 96 is installed above the side wall 1a so as to descend from the foam recovery pit section 40 side to the waterway 1 side, the used seawater dropped from the mesh belt 91 passing above the seawater guide 96. Is surely returned to the water channel 1 side without falling to the bubble recovery pit part 40 side.
Even in the foam recovery device 20D having such a configuration, the foam 4 floating on the water surface can be separated from the used seawater and recovered. Moreover, this foam collection | recovery apparatus 20D does not require the overflow dam 30. FIG.

  Further, for the above-described conveyor device, for example, as shown in FIG. 22, a modification in which the third roller 94 that causes the mesh belt 91 to travel downward is omitted, and its conveyance path and the like are particularly limited. Various embodiments are possible.

As described above, since the foam recovery apparatus of the present invention appropriately separates and removes the foam 4 from the surface of the used seawater drained by flowing through the water channel 1 after being drained from the desulfurization tower, the foam 4 is recovered. Only used seawater without water can be drained into the surrounding sea area. As a result, the problem that the bubbles 4 floating on the water surface deteriorate the landscape and the problem of environmental pollution can be solved. Moreover, about the foam 4 collect | recovered with the foam collection | recovery apparatus of each embodiment mentioned above, after conveying to the foam processing apparatus 13, as it demonstrated in 1st Embodiment, it spin-dry | dehydrates and carries out a foam component and seawater component. Can be separated.
In addition, this invention is not limited to embodiment mentioned above, In the range which does not deviate from the summary of this invention, it can change suitably.

The reference example of a foam recovery device and a foam recovery system concerning the present invention is shown, and is the figure which added the composition of land equipment to the section which looked at the foam recovery device from the flow direction. It is a top view of the foam collection | recovery apparatus which concerns on a reference structural example . It is a side view of the foam collection | recovery apparatus which concerns on a reference structural example . It is a perspective view of the principal part which shows the 1st modification of the foam collection | recovery apparatus in a reference structural example . It is a top view of the 1st modification shown in FIG. It is a top view which shows the 2nd modification of the foam collection | recovery apparatus in a reference structural example . It is a top view which shows 1st Embodiment about the foam recovery apparatus which concerns on this invention. It is a perspective view which shows the principal part about the foam collection | recovery apparatus of FIG. It is a top view which shows the modification concerning 1st Embodiment. It is a figure which shows the variable mechanism of a weir height, and is the figure which looked at the overflow weir provided in the side wall of the water channel from the foam recovery pit part side. It is sectional drawing which shows the gate board of FIG. It is a top view of FIG. It is a top view which shows a reference example about the foam collection | recovery apparatus which concerns on this invention. It is a perspective view which shows the structural example of the scraper apparatus shown in FIG. It is a figure which shows the 1st modification based on the reference example of FIG. 13 , (a) is a top view, (b) is sectional drawing. It is a figure which shows the 2nd modification based on the reference example of FIG. 13 , (a) is a top view, (b) is sectional drawing. It is a top view which shows the 3rd modification based on the reference example of FIG. It is a top view which shows the 4th modification concerning the reference example of FIG. It is a top view which shows the 5th modification concerning the reference example of FIG. It is a side view which shows a reference example about the foam collection | recovery apparatus which concerns on this invention. It is a side view which shows a reference example about the foam collection | recovery apparatus which concerns on this invention. It is a side view which shows the modification concerning the reference example of FIG. It is a side view which shows a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Waterway 1c Inclined surface 4 Foam 5,5A-5C Aeration area 10 Foam collection system 12 Suction conveyance apparatus 13 Foam treatment apparatus 20, 20A-20D, 20A ', 20D' Foam collection apparatus 30 Overflow weir 31 Gate board 40 Foam collection Pit part 43 Return flow path 50, 50A-50C Foam floating body 50D Foam holding member (curtain wall)
51 Inclined Surface 52 Curved Surface 60 Scraper Device 65 Inclined Wall Surface 66 Arc Wall 67 Rotary Scraper 80 Suction Port 81 Float 84 Ejector Portion 85 Blower 90 Squeezing Roller 91 Mesh Belt

Claims (4)

A foam recovery device that is installed in a water channel that drains the used seawater discharged from the desulfurization tower of the flue gas desulfurization apparatus that uses seawater as an absorbent, and removes and collects bubbles floating on the surface of the used seawater. Because
A foam recovery pit portion connected via an overflow weir formed on the side surface of the inclined surface intersecting the flow of the used seawater by narrowing the cross-sectional area of the water channel is provided, so as to cross the water channel The foam floating body that is held in a floating state is installed, and the foam floating on the water surface and the surface seawater flow are separated from the mainstream of the used seawater and led to the foam recovery pit section,
The foam recovery apparatus according to claim 1, wherein the foam floating body has a water portion and an underwater portion, and an inclined surface that obliquely crosses the water channel is formed on an upstream side in the flow direction of the used seawater.   The return path which connects between the said foam recovery pit part and the said water channel, isolate | separates at least one part of the collect | recovered seawater from a foam, and returns to the said water channel is provided. Foam recovery device.   The foam recovery apparatus according to claim 1, wherein the overflow weir includes a weir height variable mechanism. Bubble recovery that separates and recovers bubbles floating on the surface of the used seawater, installed in a water channel that drains the used seawater discharged from the desulfurization tower of the flue gas desulfurization equipment that uses seawater as an absorbent. A foam recovery system comprising a device,
The foam recovery apparatus according to any one of claims 1 to 3 ,
A foam treatment device for dehydrating and drying the foam collected by the foam collection device;
A foam recovery system comprising: a suction transport device that sucks the foam recovered in the foam recovery pit portion and transports the foam to the foam processing device via a flow path.

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