JP2005290719A - Contamination preventing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a contamination preventing apparatus which prevents effusion of contaminated water by suppressing the turbidity of water stored in a dammed reservoir in discharging the water, thereby preventing degradation of the water quality in a downstream river. <P>SOLUTION: The contamination preventing apparatus 1 is constructed by setting a contamination preventing film 2 having a float 5 at an upper edge thereof and a weight chain 3 mounted on a lower edge thereof, in the reservoir at a location being spaced on an upstream side away from a dam body D almost in parallel with the dam body D, and therefore an upper side of the reservoir from above a bottom layer is divided into an upstream side and a downstream side by the contamination preventing film 2, to thereby prevent the turbidity of the water in the downstream-side reservoir. According to the contamination preventing apparatus, the float 5 consists of a floating-and-sinking type float unit 5a and a fixed type float unit 5b, and the floating-and-sinking type float unit 5a is sunk to a location upper than the bottom layer of the reservoir, and water in an upper layer of the reservoir is flown from the upstream side to the downstream side of the contamination preventing film 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a pollution control device that prevents the outflow of polluted water during discharge by suppressing the turbidity of water stored in a dam reservoir.

  Conventionally, as an apparatus for preventing turbidity of water in a dam reservoir, a pollution prevention apparatus having a pollution prevention film having a float at the upper end and a weight such as a chain attached to the lower end is used.

  This pollution control device is installed substantially parallel to the dam dam body at a predetermined distance from the dam dam body to the upstream side. It is divided into the downstream side.

In this way, the flow of water flowing in from the upstream river is blocked by the anti-pollution membrane and retained on the upstream side of the anti-pollution membrane, thereby promoting the sedimentation of pollutants such as sand and mud contained in the incoming water. In addition, the plankton that causes turbidity is caused to flow downward and moved to a non-light-bearing layer where it is difficult to propagate, thereby suppressing the growth, so that downstream of the pollution control film, that is, between the pollution control device and the dam body The turbidity of the stored water is prevented (for example, see Patent Document 1).
JP-A-10-60874 (pages 2 and 3)

  However, in the pollution control device described above, when the stored water is discharged to adjust the amount of water during normal times when water with low turbidity flows from the upstream river, the upstream river generated from the discharge goes to the dam body. Since the water flow having a high flow velocity is blocked by the pollution prevention film, the water flow hit the pollution prevention film is disturbed, and a flow of stirring the water stored on the downstream side of the pollution prevention film is generated. And since the agitated and turbid water is discharged from the discharge gate of the dam levee, the water in the downstream river becomes turbid and may deteriorate the water quality.

  The present invention has been made to solve such problems, and it prevents pollution water from flowing out by suppressing turbidity of water at the time of discharge in a dam reservoir, and prevents pollution of downstream rivers. The object is to provide a device.

  In order to solve the above-mentioned problem, the pollution control device according to claim 1 is provided with a float at the upper end, and a pollution prevention film having a weight such as a chain attached at the lower end to the upstream side from the dam dam body. Anti-contamination to prevent turbidity of the stored water on the downstream side by partitioning the upper side from the bottom layer of the water storage into the upstream side and the downstream side with the anti-contamination membrane The apparatus is configured to sink at least a part of the float of the pollution prevention film above the bottom layer of the stored water so that the upper layer of the stored water flows from the upstream side to the downstream side of the pollution prevention film. It is characterized by comprising.

  The pollution control device according to claim 2, wherein a pollution prevention film having a float at the upper end and a weight such as a chain at the lower end is provided at a distance from the dam dam body to the upstream side. An anti-contamination device which is installed substantially in parallel and prevents the turbidity of the stored water on the downstream side by dividing the upper side from the bottom layer of the stored water into an upstream side and a downstream side by the anti-contamination membrane, A part of the longitudinal direction of the float is composed of a float / float type float, and when the float / float type float is floated on the surface of the water, an extra length is provided so that the float / float type floats. It is characterized in that the upper layer portion of the stored water is circulated from the upstream side to the downstream side of the anti-contamination membrane by sinking upward.

  According to the pollution control apparatus of Claim 1 and 2, water storage is divided into the upstream and the downstream by the pollution prevention film, and the inflow water from the upstream river is retained on the upstream side of the pollution prevention film. In addition to preventing sedimentation of polluted components such as soil and sand and preventing turbidity of the stored water on the downstream side, the downstream side can also be used during normal discharge when low turbidity water flows from the upstream river. The turbidity of stored water can be prevented and the outflow of polluted water to the downstream river can be prevented.

  That is, when draining the stored water during normal times when non-turbid water flows from the upstream river, at least a part of the float is sunk, or the floating float is sunk, and the upper layer of the stored water is If it is made to circulate from the upstream side to the downstream side of the pollution prevention membrane, the inflowing water can be smoothly flowed to the downstream side without being blocked by the pollution prevention membrane. Can be suppressed. For this reason, the water storage between the anti-pollution membrane and the dam body is less likely to be turbid, and water with less turbidity can be discharged to the downstream river.

  In such a pollution prevention device according to claim 1, all the floats may be made to float and sink, so that all the floats may sink, or a predetermined distance may be provided to sink a plurality of locations. May be.

  Further, as in the pollution prevention device according to claim 2, when the surplus length is set so as to be in a slack state when the float type float is floated on the water surface, the fixed floats on both sides are set during the settlement. Therefore, it becomes easy to sink, and the upper layer part of the stored water can be smoothly distributed.

  The pollution control device according to claim 3 is a part of the float that sinks, or a part that floats and sinks by supplying and exhausting a float-float type float with a structure that can be filled with air, or a part that sinks the exhausted float, or The float / sink type float is configured to sink at least by the weight of the weight.

  According to the pollution control device of the third aspect, the structure of the device is not complicated, and it is possible to float or sink the floated part or the floated part of the float simply by supplying and exhausting air. Therefore, there is an advantage that it is possible to easily distribute the water storage upper layer.

  The pollution control device according to claim 4 is provided with a lateral hydraulic pressure belt attached to a position corresponding to a lower side of the upper layer of the stored water in the pollution prevention film, and both ends of the hydraulic hydraulic belt are attached to anchors or the like. It is characterized by stretching.

  According to such a pollution control device according to claim 4, since the flowing water pressure associated with the discharge can be provided by the flowing water pressure belt, when the subsidence portion or the floating type float is submerged in the float Therefore, it is possible to prevent the floating due to the flowing water pressure.

  That is, when the anti-contamination membrane is pushed downstream by the flowing water pressure associated with the discharge, the anti-flow water pressure belt enters a tension state and supports the anti-contamination membrane against the flowing water pressure. At this time, the lower side of the anti-flow hydraulic pressure belt of the anti-pollution membrane is maintained in a suspended state because of the downward force due to the weight, but the upper side of the anti-flow hydraulic pressure belt is caused by water flow. Since a force that pushes down downstream acts on the anti-flow hydraulic belt as a fulcrum, an upward force (that is, a direction of rising) acts on a portion of the float that has lost buoyancy or a float-float type float. This is because it becomes difficult.

  The pollution control device according to claim 5, wherein the weight is continuously provided at a lower end portion of the pollution prevention film, and both ends of the weight are attached to an anchor or the like with a mooring line to stretch the weight. It is characterized by a tension part that resists pressure.

  According to such a pollution prevention device of claim 5, the same action as in the case of the anti-flow hydraulic belt described in claim 4 is caused with the weight as a fulcrum in the pollution prevention film. Therefore, when the floated part or the floatable float is subsidized, the float can be prevented from rising.

  In other words, the weight such as a chain is continuously provided at the lower end of the pollution prevention film, and both ends of the weight are attached to anchors or the like with a mooring line, thereby being discharged to the pollution prevention film. When the flowing water pressure is applied, the weight supports the antifouling film against the flowing water pressure.

  Thereby, when sinking a portion of the float or the float-floating type float, since the pollution prevention film in which these are disposed has no buoyancy, it is in a state of being pushed down downstream with the weight as a fulcrum, This is because an upward force (ie, a rising direction) is less likely to act.

  The pollution control device according to claim 6 is at least one of a lower end portion of a portion of the float to be sunk, an upper end portion of a pollution prevention film of a portion of the float to be sunk, or at least the floatation type float. An auxiliary weight for sinking such as a chain is provided at either the lower end or the upper end of the antifouling film provided with the float / float type float.

  According to such a pollution control device according to claim 6, at least one of the lower end of the part of the float to be sunk, the upper end of the pollution prevention film of the part to be sunk, or at least the floatation type By providing an auxiliary weight for subsidence such as a chain on either the lower end of the float or the upper end of the antifouling membrane provided with the float / float type float, a force to add downward is applied, i.e. It is possible to sink the portion of the float and the float / float type float more quickly, and more reliably prevent the float from rising due to flowing water pressure.

  The pollution control device according to claim 7 is a part of the float that sinks, or a part of the float that sinks by connecting the float to a float that floats on the surface of the water. It is characterized by limiting the subsidence depth of the float.

  According to the pollution control device of the seventh aspect, since the subsidence portion of the float or the subsidence depth of the float / float type float can be limited, it is easy to handle without being oversunk. In addition, by setting the length of the rope in advance to a length corresponding to the depth of the upper layer of the water storage, it is not necessary to adjust the sinking portion of the float or the sinking amount of the floating float. This makes it easy to perform subsidence work.

  The pollution control device of the present invention made with the above-described means has the following effects.

  1. When discharging during normal times, water with less turbidity flowing from the upstream river can be smoothly guided to the discharge gate of the dam dam body, so that the flow of stirring the water does not occur and the water does not become turbid. Therefore, since water without turbidity can be discharged, there is no deterioration in water quality of the downstream river due to turbid water, and the load on the natural environment accompanying the discharge can be reduced.

  2. The anti-flow hydraulic belt is attached to the anti-contamination membrane in the lateral direction, and the weight at the lower end is used as the tension part, so that when the float sinks or the float floats, the lift is more reliable. Therefore, the water storage upper layer can be smoothly circulated and can be discharged stably. Further, when the sinking auxiliary weight is attached, the float sinking part and the float-float type float sink quickly, and it becomes difficult to lift, so that more stable discharge is possible.

  3. If you place a float on the surface of the water and connect the float and the part of the float that sinks, or the float and sink type float to limit the depth of the sink, they will not sink too much The device can be easily operated and can be easily handled.

  4). If the part of the float that sinks or the float-float type float is subtracted when not discharging, it can be used as a ship gate, so there is no need to provide a separate ship gate in the device, and the structure can be simplified. The manufacturing cost can be reduced.

  Hereinafter, an embodiment of a pollution control device according to the present invention will be described with reference to FIGS.

  As shown in FIGS. 1 and 2, the pollution prevention device 1 has a pollution prevention film 2 having a float 5 at its upper end and a weight chain 3 at its lower end, and is predetermined upstream from the dam body D. The dam levee body D is installed approximately parallel to the distance. In this way, the pollution prevention film 2 partitions the upper side from the bottom layer of the stored water into an upstream side and a downstream side.

  As shown in FIG. 3, the pollution prevention film 2 is formed by connecting a plurality of pollution prevention films 2 a and extending the length, and each pollution prevention film 2 a has a long and narrow shape constituting a float 5. The float unit (having the symbol 5a or 5b) and the weight chain unit 3a constituting the weight chain 3 are disposed.

  The float is divided into a float type float unit 5a and a fixed type float unit 5b, and the two pollution prevention membrane units 2a arranged in the central portion are provided with the float type float unit 5a, and the rest A fixed float single body 5b is disposed on the pollution prevention film single body 2a. And the pollution prevention membrane single-piece | unit 2a which provided the ship gate 21 instead of the float single-piece | unit is interposed in a part of the part by which the pollution prevention membrane single-piece | unit 2a which has the fixed type float single piece 5b is arrange | positioned continuously. The work vessel that performs maintenance etc. can be passed.

  As shown in FIG. 4 (a), the fixed type float 5b is obtained by sewing a tarpaulin into a slender bag shape and storing a cylindrical foam F having a diameter of about 400 mm as a buoyant body in a laid state. , Always floating on the surface of the water. On the other hand, as shown in FIG. 4B, the float / sink type float unit 5a is a synthetic rubber rubber tube having a circular section having a diameter of about 400 mm and having physical properties such as weather resistance, so that air can be taken in and out. It has become.

  As shown in FIG. 4 (c), the floats 5a and 5b are connected to each other via connecting fittings 6. In order to prevent the connecting portions from sinking due to their own weight, the box type is used. The auxiliary float 7 made of FRP (fiber reinforced plastic) is attached so as to be sandwiched from both sides (see FIG. 5A).

  In each float 5a, 5b, a horizontally long rectangular film body formed of a polyester sheet having a tensile strength of 800 kgf / 3 cm is suspended in such a length that the lower end reaches a water depth of 10 to 15 m. It has become. As shown in FIG. 5 (b), the film body has a reinforcing belt 8 sewn in a lattice shape, and, as shown in FIG. 5 (c), a weight chain having an epoxy tar coating on the lower end. 3a is attached.

  And as shown to Fig.6 (a), while adjoining the film body of the pollution prevention film single-piece | unit 2a, a side end part is tied and connected with a string, and it attaches to the edge part of the sideways reinforcement belt 8. FIG. The shackle 11 is attached to the D tube 10 and the reinforcement belts 8 are connected to each other.

  Further, a belt-like polyester anti-flow hydraulic pressure belt 22 is sewn to the film body of the pollution prevention film alone 2a in parallel with the laterally-oriented reinforcing belt 8. The anti-flow hydraulic belts 22 provided on the adjacent anti-pollution membranes 2 a are connected by connecting the D pipes 10 at the ends with the shackle 11 in the same manner as the reinforcing belt 8.

  Both ends of the anti-flow hydraulic belt 22 connected in this manner are respectively attached and stretched to the anchor block 12 installed on the shore by ropes 13.

  On one bank B, an air supply compressor 14 is installed (see FIG. 2). One end of the air supply / exhaust hose 15 connected to the compressor 14 and extending toward the opposite bank is branched off in the middle. (A) As shown in (b), the end of the float / float type float unit 5a closer to the shore B where the compressor 14 is located, and the opposite end of the adjacent float / float type float unit 5a (there is the compressor 14) Are connected to the opposite side of shore B). An exhaust valve 15 a and a supply / exhaust switching valve 15 b are interposed in the land portion of the supply / exhaust hose 15.

  The float / float type float unit 5a is connected at the connecting portion by a communication hose 18 having short ends, so that air can flow through both the float / float type float units 5a.

  In addition, a float 19 is installed in the vicinity of each float / float type float 5a so that a buoyant body is housed inside and is always floated on the water surface, and is connected to the float / float float 5a by a rope 20 having a length of about 3 m. (See FIGS. 1 and 2). The length of the rope 20 is appropriately set according to the depth of the upstream river, the state of the inflowing water, and the like.

  In addition, the strength of the anti-flow hydraulic belt 22 is set low between the anti-contamination membrane unit 2a provided with the float / float type float unit 5a and the anti-contamination membrane unit 2a provided with the passage gate 21. If the flowing anti-contamination membrane 2a is applied to the device and the flowing water pressure exceeds the expected level, the anti-contamination membrane 2a (also called a breaker fence) will be damaged first, and the durability of the device will be estimated. It can be. Therefore, if the pollution prevention film 2a is broken, the apparatus can be recovered and further damage to the apparatus can be prevented.

  Next, the operation procedure of this pollution prevention apparatus 1 is demonstrated.

  When the dam is not discharged, the float 5 is floated to the surface of the water, and the anti-contamination film 2 partitions the upper part of the stored water into an upstream side and a downstream side (see FIG. 1). And the water which flows in from an upstream river is made to stay in the upstream of the pollution prevention membrane 2, and the sedimentation of turbid components, such as soil and sand contained in water, is promoted, and the water storage of the downstream of the pollution prevention membrane 2 is carried out. Avoid turbidity.

  Then, when discharging at a normal time when water with less turbidity flows from the upstream river, the exhaust valve 15a is opened before opening the discharge gate G (at this time, the supply / exhaust switching valve 15b is Closed). Then, the air inside the two float / float type single floats 5 a is discharged to the outside from the exhaust valve 15 a through the air supply / exhaust hose 15.

  In this way, by lowering the buoyancy of the two float / float type floats 5a, the float / sink type floats 5a and the like are lowered by their own weight and the weight of the weight chain 3. Since the floated and floated float unit 5a that has sunk is connected to the float 19 on the water surface by a rope 20 having a length of about 3 m, as shown in FIG. 8, it stops at a position at a depth of about 3 m. Then, the upper layer part of the water storage partitioned by the pollution prevention film 2 can be distributed between the upstream side and the downstream side.

  When the discharge gate G of the dam dam body is opened in this state, the water with less turbidity flowing from the upstream river passes smoothly above the sinking float unit 5a and is smoothly guided to the discharge gate G. . For this reason, the flow of stirring that makes the stored water turbid does not occur, and clear water with less turbidity can be discharged to the downstream river.

  Further, when the stored water is discharged, a water flow having a high flow velocity from the upstream side toward the discharge gate G is generated, so that the pollution prevention film 2 receives a large flowing water pressure due to this flowing water. And although the pollution prevention film 2 is pushed downstream by the flowing water pressure, both ends are supported so as to resist the flowing water pressure by the anti-flow water pressure belts 22 attached to the anchors 12 on both banks B. The

  As a result, as shown in FIG. 9, the pollution prevention film 2 below the anti-flow hydraulic pressure belt 22 is maintained in a state of being suspended almost directly by the weight of the weight chain 3. A force that pushes down on the downstream side with the anti-flow hydraulic pressure belt 22 as a fulcrum acts on the anti-pollution film single body 2a (including the float / float type float single body 5a) on the upper side of the flowing water pressure belt 22. Therefore, the upward force is less likely to act, so that the float / float type float unit 2a is difficult to lift.

  In this case, if the weight block 9 is attached as an auxiliary weight for subsidence to the lower end portion of the float / float type float unit 5a or the upper end portion of the pollution prevention film unit 2a, it is possible to more reliably prevent lifting due to flowing water pressure. (See FIG. 6B). Also, if the weight block 9 near the center of the two float / float type floats 2a, that is, near the connecting portion is increased in weight or arranged with a narrow pitch, when the subsidence is caused to sink, In the beginning, air can be smoothly discharged from both sides to which the air supply / exhaust hose 15 is connected, so that the floating float unit 2a can be surely and quickly settled without air remaining inside. Become. Further, it is possible to prevent the connecting portion between the float / sink type float unit 2a and the fixed type float unit 5b from sinking as the float / sink type float unit 2a sinks.

  When the discharge is completed, the discharge gate G is closed, the exhaust valve 15a is closed, the supply / exhaust switching valve 15b is opened, and the compressor 14 is driven. Then, compressed air is supplied from the supply / exhaust hose 15 to each float / float type float unit 5a to give buoyancy and to float on the water surface.

  In this embodiment, the ship gate 21 is provided. However, if the float / float type float unit 5a is lowered to allow the work ship to pass, the ship gate 21 can be omitted and the structure can be simplified. .

  As shown in FIG. 10, the pollution prevention apparatus configured in this way has a length in the longitudinal direction of the float-float type float unit 5 a so as to be loose when it floats on the water surface. It can also be left. In this case, in a state where the anti-flow hydraulic pressure belt shorter than the lateral length is folded on the anti-contamination membrane attached over the entire length in the longitudinal direction of the float / sink type float unit 5a, the extra length of the anti-contamination membrane unit is folded. Sewing.

  In this way, by allowing the float / sink type float unit 5a to have an extra length, when sinking, it is difficult to be pulled by the fixed type float unit 5b on both sides so that it can be smoothly sunk. Further, the anti-contamination membrane attached to the float / float type float unit 5a may have an extra length only in the upper portion, for example, the anti-contamination membrane unit above the anti-flow hydraulic belt is inverted trapezoidal. The upper side may be wide.

  Further, the float may be constituted by only the float / sink type float, and the entire float may be sunk to circulate the stored water upper layer.

  Then, instead of the anti-flow hydraulic pressure belt, both ends of the weight chain are attached to the land anchors with ropes, etc. It is possible to prevent the floating of the single type float or the like.

  On the other hand, when the water pressure applied to the pollution control film is weak, such as when the water flow speed associated with the discharge is slow, it is possible to prevent the floating float / float type float from rising due to the weight of the pollution prevention film and the weight of the weight chain. Since it can, the anti-flow hydraulic belt can be omitted and the structure can be simplified. In this case, the anti-fouling film is moored at both ends of a reinforcement belt (tension belt), a float, etc. provided on the film body with an anchor rope or the like on the shore anchor block.

  And when sinking a float-float type float alone, the inside air is discharged to lose buoyancy and sink due to its own weight or the weight of the weight chain. If the weight chains located in the vicinity of the connecting portions are made heavy or doubled, the float / float type float can be sunk reliably and quickly. In other words, if the buoyancy is lost by discharging the air of the float / float float unit, the settlement starts from the connecting part of the float / float float unit, and the air is smoothly discharged from both sides to which the air supply / exhaust hose is connected without remaining. It is because it can be made. Furthermore, it is possible to prevent the connecting portion between the float / sink type float unit and the fixed type float unit from sinking as the float / sink type float unit sinks.

  Then, the subsidence depth of the float / float type float unit may be adjusted by the amount of air to be supplied. In this case, the float can be used as a safety device for suppressing excessive settlement. Further, the number and position of the exhaust valves and the supply / exhaust switching valves can be arbitrarily set. For example, these valves can be mounted on the float and disposed on the water, and can be configured to be operated by remote operation.

It is explanatory drawing which shows the installation state of the pollution control apparatus concerning this invention. It is explanatory drawing which showed the arrangement | positioning relationship between a pollution prevention apparatus and a dam dam body. It is a front view which shows the float and pollution prevention film | membrane part of a pollution prevention apparatus. (A) is the elements on larger scale of the A section in FIG. 3, (b) is the XX direction arrow view in FIG. 3, (c) is the elements on larger scale of the B section in FIG. (A) is a top view of the connection part of the float single-piece | unit, (b) is the elements on larger scale of the C section in FIG. 3, (c) is the elements on larger scale of the D section in FIG. (A) is the elements on larger scale of the E section in FIG. 3, (b) is the elements on larger scale of the pollution prevention film | membrane which shows the state which attached the weight block to the pollution prevention film | membrane upper part. (A) is explanatory drawing which shows arrangement | positioning of an air supply / exhaust hose, (b) is the elements on larger scale of the yy direction arrow in (a). It is explanatory drawing which shows the state which sunk the float / float type float simple substance. It is explanatory drawing which shows the state of the pollution prevention film | membrane at the time of discharging stored water. It is a top view which shows the state which floated the float-and-sink type float which gave extra length on the water surface.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pollution prevention apparatus 2 Pollution prevention film 3 Weight chain 5 Float 5a Floating / floating type single unit 5b Fixed type floating unit 14 Anchor 19 Float 22 Anti-flow hydraulic belt D Dam dam body

Claims (7)

The bottom layer of the water storage is provided with a pollution prevention membrane equipped with a float at the top and a weight such as a chain at the bottom at a distance from the dam dam body to the upstream side and approximately parallel to the dam dam body. An anti-contamination device that prevents turbidity of stored water on the downstream side by partitioning the upper side into an upstream side and a downstream side with the anti-contamination membrane,
The upper layer part of the stored water is circulated from the upstream side to the downstream side of the pollution control film by sinking at least a part of the float of the pollution prevention film above the bottom layer part of the stored water. A pollution control device. The bottom layer of the water storage is provided with a pollution prevention membrane equipped with a float at the top and a weight such as a chain at the bottom at a distance from the dam dam body to the upstream side and approximately parallel to the dam dam body. An anti-contamination device that prevents turbidity of stored water on the downstream side by partitioning the upper side into an upstream side and a downstream side with the anti-contamination membrane,
A part of the float in the longitudinal direction is composed of a float / float type float, and when the float / float type float is floated on the water surface, it has a surplus length so as to be loosened. An anti-turbidity device characterized in that the upper layer portion of the stored water is circulated from the upstream side to the downstream side of the anti-contamination membrane by being submerged above.   A portion of the float that sinks or the floatable float is made to be capable of floating by supplying and exhausting air in a configuration that can be filled with air, and the exhausted float sinkable portion or the floatable float is at least The pollution control device according to claim 1, wherein the pollution control device is configured to sink with a weight of a weight.   A anti-flow hydraulic belt is attached to the position corresponding to the lower side of the upper layer of the stored water in the anti-contamination membrane, and both ends of the anti-flow hydraulic belt are attached to an anchor or the like and stretched. The pollution control device according to claim 1 or 2, characterized by the above-mentioned.   The weight is continuously provided at the lower end portion of the antifouling film, and both ends of the weight are attached to an anchor or the like with a mooring cable, and the weight is used as a tension portion that resists flowing water pressure. The pollution control device according to claim 1 or 2 characterized by things.   At least one of the lower end of the floated portion of the float and the upper end of the pollution prevention film of the lowered portion, or at least the lower end of the floatable float, or the pollution prevention provided with the floatable float The pollution control device according to any one of claims 1 to 5, wherein an auxiliary weight for subsidence such as a chain is provided at any one of the upper end portions of the membrane. Claim that the subsidence depth of the float or the subsidence type float is limited by connecting the subsidence part of the float or the subsidence float to a float installed on the water surface with a rope. Item 7. The pollution control device according to any one of Items 1 to 6.

Images