WO2005110927A1

WO2005110927A1 - Scum skimmer

Info

Publication number: WO2005110927A1
Application number: PCT/KR2005/001426
Authority: WO
Inventors: Gi-Ho Na; Su-Youn Lee; Jin-Woong Choi
Original assignee: Philtec Co., Ltd.
Priority date: 2004-05-17
Filing date: 2005-05-16
Publication date: 2005-11-24
Also published as: KR100758345B1; KR20060043476A

Abstract

A scum skimmer for collecting only scum using a head of water. The scum skimmer includes a main body having a flotation device, a water introduction passage disposed at the front side thereof, a cave space having an opened top and four closed sides and formed at the rear side of the water introduction passage, and a water collecting container and a scum collecting container respectively formed at the front and rear sides of the cave space by partitioning a partition, and a water collecting device disposed in the water collecting container to receive water and scum on the water surface through the water introduction passage by generating a head of water under the water surface and to discharge the introduced water such that the introduced scum floats and is accumulated on the water surface and overflows the partition to be skimmed in the scum collecting container.

Description

SCUM SKIMMER

BACKGROUND OF THE INVENTION

Field of the Invention The present invention relates to a scum skimmer for skimming scum at the water surface of a water purification plant and floating oil generated due to lake or sea contamination or accidents, and more particularly to a scum skimmer for simultaneously receiving water and scum using a head of water and for collecting and skimming only floating scum.

Description of the Related Art Generally, a great deal of scum is formed when purifying water in a water purification plant and oil floats on the water surface in the case of shipwrecks in the river, lake, or ocean.

Such scum contaminates water and destroys ecosystem. For this reason, various scum skimmers for removing scum are known and used. Among the conventional scum skimmers, Korean Utility Model Registration Application No. 2002-1325, entitled Siphon type scum skimmer' (hereinafter referred to as scum skimmer according to a first embodiment of the conventional art' ) and Korean Utility Model Registration Application No. 2001-22967, entitled ^vscum skimming apparatus of a floating purification plant' (hereinafter referred to as 'scum skimmer according to a second embodiment of the conventional art' ) are known and will be described in the following. First, the scum skimmer according to the first embodiment of the conventional art is structured such that a scum introduction passage of a hollow cylindrical scum skimmer according to the first embodiment of the conventional art supported to pivot in a settling basin and positioned on L e water surface by a weight skims the scum floating on the water surface, the scum skimmer according to the first embodiment of the conventional art rotates to position the scum introduction passage on the water surface when a siphon weight disposed at the end of the weight and connected to the scum skimmer according to the first embodiment of the conventional art by a wire is filled with water and lowered so as to discharge the collected scum. However, the scum skimmer according to the first embodiment of the conventional art simply blocks and skims the scum in the passage through which the scum passes together with a flow and the remove efficiency of the scum is lower. In other words, the scum flows together with process water and is interrupted by the scum skimmer according to the first embodiment of the conventional art so that the scum is gathered in the neighborhood of the scum introduction passage. Since there is no water flow in the scum skimmer according to the first embodiment of the conventional art, the scum cannot be easily introduced into the scum skimmer according to the first embodiment of the conventional art. Accordingly, the scum cannot be effectively skimmed. Moreover, the scum skimmer according to the second embodiment of the conventional art is structured such that a rotational scum skimmer having blades disposed in the radial direction is installed to rotate at a side of a settling basin so that the blades pump out the scum on the water surface together with water to a scum discharging passage.

However, the scum skimmer according to the second embodiment of the conventional art has shortcomings in that the scum is discharged together with a great deal of water and in that the scum skimmer cannot remove a great deal of scum in a short time.

SUMMARY OF THE INVENTION Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a scum skimmer capable of gathering various bubbles, oil, and the like (hereinafter refer to as "scum") floating on the water surface of a purification plant, lakes, rivers, or oceans using a head of water and skimming only scum. Moreover, it is another object of the present invention to provide a scum skimmer for skimming a great deal of scum in a short time by collecting scum using a head of water and the principle that scum floats. In accordance with an aspect of the present invention, the above and other objects can be accomplished by the provision of a scum skimmer including: a main body including a flotation device for providing buoyancy to the main body, a water introduction passage disposed at the front side thereof, a cave space having an opened top and four closed sides and formed at the rear side of the water introduction passage, and a water collecting container and a scum collecting container respectively formed at the front and rear sides of the cave space by partitioning the cave space with a partition, and a water collecting device disposed in the water collecting container to receive water and scum on the water surface through the water introduction passage by generating a head of water under the water surface and to discharge the introduced water such that the introduced scum floats on the water surface to be accumulated and overflows the partition and is separated and skimmed into the scum collecting container. In accordance with an aspect of the present invention, the above and other objects can be accomplished by the provision of a scum skimmer including: a main body including a flotation device for providing buoyancy to the main body, a water introduction passage disposed around the outer circumference of the main body, a cave space having a closed outer circumference and disposed in the water introduction passage, and a water collecting container and a scum collecting container respectively formed in the outer side and in the inner side of the cave space by partitioning the cave space with a partition, and a water collecting device disposed in the water collecting container to receive water and scum on the v.'ater surface through the water introduction passage by generating a head of water under the water surface and to discharge the introduced water such that the introduced scum floats on the water surface to be accumulated and overflows the partition and is separated and skimmed in the scum collecting container.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: Fig. 1 is a perspective view illustrating a scum skimmer according to a first preferred embodiment of the present invention; Fig. 2 is a sectional view taken along the line A-A in Fig. 1; Fig. 3 is a sectional view taken along the line B-B in Fig. 1; Fig. 4 is a perspective view illustrating another example of a water introduction passage of the scum skimmer according to the first preferred embodiment of the present invention; Fig. 5 is a perspective view illustrating still another example of a water introduction passage of the scum skimmer according to the first preferred embodiment of the present invention; Fig. 6 is a schematic sectional view illustrating another example of a discharging device of the scum skimmer according to the first preferred embodiment of the present invention; Fig. 7 is a sectional view illustrating another example of a pump of the scum skimmer according to the first preferred embodiment of the present invention; Fig 8 is a perspective view illustrating a scum skimmer according to a second preferred embodiment of the present invention; Fig. 9 is a sectional view taken along the line C-C in Fig. 8; Fig. 10 is a perspective view illustrating another example of a scum skimmer according to the second preferred embodiment of the present invention; and Fig. 11 is a sectional view taken along the line D-D in Fig. 10.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings . Fig. 1 is a perspective view illustrating a scum skimmer according to a first preferred embodiment of the present invention, Fig. 2 is a sectional view taken along the line A-A in Fig. 1, and Fig. 3 is a sectional view taken along the line B-B in Fig. 1. The scum skimmer according to the first preferred embodiment of the present invention includes a main body 1 including a flotation device 15 for providing buoyancy to the main body 1, a water introduction passage 11 disposed at the front side thereof, a cave space having an opened top and four closed sides and formed at the rear side of the water introduction passage 11, a water collecting container 13 and a scum collecting container 14 respectively formed at the front and rear sides of the cave space by partitioning the cave space with a partition 12, and a water collecting device 2 disposed in the water collecting container 13 to receive water and scum on the water surface through the water introduction passage 11 by generating a head of water under the water surface and to discharge the introduced water such that the introduced scum floats on the water surface to be accumulated and overflows the partition 12 and is separated and skimmed in the scum collecting container 14. The scum skimmer according to the first preferred embodiment of the present invention further includes a scum discharging device 141 for compulsorily transporting the scum containing water in the scum collecting container 14 to land or to another ship. Thus, the scum discharging ^' device 141, as shown in Fig. 2, includes a discharge pump 142 disposed in the scum collecting container 14 to compulsorily transport the scum containing water to land or to another ship. In other words, the discharge pump 142 is disposed in the scum collecting container 14, compulsorily sucks the scum in the scum collecting container 14, and compulsorily transports the sucked scum to land such as the riverside, the seashore, or the like, or to another ship through a hose. Moreover, the water collecting device 2 includes a pumping device 21 disposed in the water collecting container 13 to generate a head of water under the water surface such that the water and the scum are introduced into the water collecting container, and a drain 22 formed in the water collecting container to drain only water from the water and scum introduced into the water collecting container to the water. The pumping device 21 is installed in the water collecting container 13 and includes a motor 212 for generating a head of water and a propeller 211 driven by the motor 212. In other words, since the propeller 211 is disposed in the water collecting container 13 and performs the operations that the water and the scum are compulsorily introduced into the water collecting container 13 due to the head of water and continuously discharged out of the water collecting container 13. In addition, the pumping device 21 includes a horizontal partition 213 having an intermediate hole 214 for partitioning the lower side of the water collecting container 13 surrounding the propeller 211 in the horizontal direction, and a water vortex prevention net 214a disposed in the upper side of the propeller 211, i.e. the upper side of the intermediate hole 214 to prevent water contained in the upper side of the horizontal partition 213 when the water is introduced into the intermediate hole 214 from rotating. In other words, the water vortex prevention net 214a prevents the rotation force of the water generated during the rotation of the propeller 211 from being transmitted to the upper side of the horizontal partition 213. Namely, since the water vortex net 214a is a net, the water vortex generated during the rotation of the propeller 211 is prevented. Meanwhile, the water collecting container 13 further includes a conventional level sensor 23 installed at the intermediate portion thereof, the scum skimmer further includes a controller 24 connected to the level sensor 23 and the motor 212 to receive the level of the water collecting container 13 from the level sensor 23 in real time and to control the rotation speed of the motor 212. In other words, the level sensor 23 detects the level of the water collecting container 13 and is installed to a sidewall of the water collecting container 13 where the level is most easily detected by an installation device. Hereinafter, the scum skimmer structured as described above according to the first preferred embodiment of the present invention will be described in detail as follows. As shown in Figs. 1 to 3, the drain 22 further includes a valve 222 for opening and closing the drain 22. Thus, when the scum skimmer according to the first preferred embodiment of the present invention is not operated, the valve 222 is closed to prevent the scum skimmer according to the first preferred embodiment of the present invention from sinking. Rotating rudders 223 are further installed at the outside of the drain 22 to adjust the moving direction and speed of the scum skimmer according to the first preferred embodiment of the present invention. In other words, the rudders 223 are rotatably installed to shafts protruded from the outside of the main body 1 by fixing devices and the direction and angle of the rudders 223 are easily adjusted by releasing and fixing the fixing devices . Moreover, the drain 22 further includes a drainpipe 221 for draining water to the water in front of the water introduction passage 11. Thus, since the water is drained to the water in front of the water introduction passage 11 so that scum contained in the drain water can be skimmed again. In addition, in front of the water introduction passage 11, a pair of expanded passage guides 111 is installed at the front side of the water introduction passage 11 to freely pivot about hinges 12 and guides scum to the water introduction passage 11 by submersing the lower sides thereof to a predetermined depth. The expanded passage guides 111 may have a plurality of blocking plates or oil fences extended from the front sides thereof so that scum is skimmed while being prevented from flowing to the outsides of the expanded passage guides 211 and the blocking plates or oil fences. In other words, the blocking plates or the oil fences extended from respective front sides of the expanded passage guides 111 prevent the scum between the blocking plates or the oil fences from flowing out of the blocking plates or the oil fences while skimming the scum. Meanwhile, the flotation device 15 includes protruding plates 151 protruded from lateral sides of the main body 1 and formed with through-holes 151, and floaters (not shown) or air tanks 153 installed to the upper sides of the protruding plates 151 to move up and down along long bolt shafts 155 and fixed by nuts to adjust the submersing level of the main body 1. In other words, according to the positions of the nuts fastened to the bolt shafts 155, the floating levels of the air tanks 153 are adjusted so that the sinking level of the main body 1 can be adjusted. Hereinafter, the operation of the scum skimmer according to the first preferred embodiment ^' of the present invention will be described as follows. As shown in Figs. 1 to 3, a predetermined amount of air is injected into the air tanks 153 of the flotation device 15 through air injection holes 154 so as to adjust the floating level of the main body 1. Thus, the water introduction passage 11 provided at the front side of the main body 1 is submersed directly below the water surface. In addition, the nuts fastened to the bolt shafts 155 provided at the upper sides of the air tanks 153 are fastened or released so that the floating level of the air tanks 153 is adjusted. The propeller 211 of the pumping device 21 provided in the water collecting container 13 is rotated so that water and scum on the water surface are introduced into the water collecting container 13 from the water introduction passage 11. Water is drained to the water through the drain 22 provided at the lower side of the water collecting container 13 and the scum is accumulated on the upper side of the water collecting container 13. In other words, when rotating the propeller 211 by the motor 212, a force of introducing water on the water surface into the water collecting container 13 is generated at the lower side of the water collecting container 13. When the water is introduced into the water collecting container 13, due to a head of water, the water on the water surface flows into the water collecting container 13 through the water introduction passage 11. Thus, the level of the water collecting container 13 becomes lower than the level of the water surface, and the scum is continuously accumulated on the lowered water surface in the water collecting container 13. As described above, when the scum is continuously accumulated on the upper side of the water collecting container 13, the height of the accumulated scum becomes higher. Due to the increased height of the accumulated scum, the scum is skimmed into the scum collecting container 14. The scum collected in the scum collecting container 14 contains water. In addition, the scum collecting container 14 includes a scum discharging pump 142 for discharging the collected scum. The scum discharging pump 141 easily transports the scum collected in a collecting tank 31 to another ship or to land such as riverside, or seashore so that the skimming of the scum can be continuously performed. Therefore, due to the structure and operation as described above, the objects of the present invention of receiving water and scum on the water surface using a head of water simultaneously and collecting and recovering only the floating scum and of collecting a great deal^' of scum in a short time can be achieved. By recovering the scum without being mixed with water, the scum skimming capacity of a ship can be maximized so that oil spills can be rapidly managed. Meanwhile, the water collecting container 13 further includes the conventional level sensor 23 installed at the intermediate portion thereof, the scum skimmer further includes the controller 24 provided between the level sensor 23 and the motor 211 to receive the level of the water collecting container 13 from the level sensor 23 in real time and to control the rotation speed of the motor 212. Thus, when the level sensor 23 detects the current water level in real time and the level is lowered, the controller 24 recognizes the lowered level and reduces the rotation speed of the motor to raise the level. On the contrary, when the level is raised, the controller 24 recognizes the risen level and increases the rotation speed of the motor 211 to lower the level . Fig. 4 is a perspective view illustrating another example of a water introduction passage of the scum skimmer according to the first preferred embodiment of the present invention. The water introduction passage 11 further includes a wave-breaking rotating body 113 disposed at the front side of the expanded passage guides 111 provided at the front side of the water introduction passage 11 and including a horizontal rotation shaft 115 protruded from the front sides of the expanded passage guides 111 and a plurality of horizontal blades 114 installed around the horizontal shaft 115. Thus, the wave-breaking rotating body 113 blocks waves coming to the front side of the water introduction passage 11 so that water of gentle waves and scum enter the water introduction passage 11. In other words, the wave-breaking rotating body 113 prevents a great deal of water and scum from entering the water introduction passage 11 so that collecting efficiency of scum is prevented from being deteriorated. Moreover, the wave-breaking rotating body 113 for water- blocking use is rotated during the movement of the main body 1 on the water surface and performs the function of making the scum flow enter the water introduction passage 11 and blocking water by being rotated. Fig. 5 is a perspective view illustrating still another example of a water introduction passage of the scum skimmer according to the first preferred embodiment of the present invention. The water introduction passage 11 is downwardly inclined from the front side to the rear side thereof. Thus, since the water introduction passage 11 is downwardly inclined from the front side to the rear side thereof, water and scum on the water surface are smoothly introduced into the water collecting container 13. Therefore, the scum collecting efficiency of the scum skimmer is enhanced when operating the scum skimmer according to the first preferred embodiment of the present invention. Fig. 6 is a schematic sectional view illustrating another example of a discharging device of the scum skimmer according to the first preferred embodiment of the present invention. The discharging device 141 includes a discharging pump 143 provided on land or on a ship to discharge the scum containing water contained in the scum collecting container 14 to land or to another ship through a hose. Thus, since the discharging pump 143 is installed on land or in a ship, total weight of the scum skimmer according to the first preferred embodiment of the present invention is reduced so that the mobility of the scum skimmer according to the first preferred embodiment of the present invention is enhanced, and the volume of the scum collecting container 14 is increased so that the recovery efficiency of scum is more enhanced. Fig. 7 is a sectional view illustrating another example of a pump of the scum skimmer according to the first preferred embodiment of the present invention. The pumping device includes a submersible pump 215 disposed on the bottom of the water collecting container 13 to compulsorily discharge water in the water collecting container 13 through the drain 22. In other words, by using a water-proof submersible pump

215 as the pumping device 21 for introducing water and scum by generating a head of water, the structure of the scum skimmer is simplified so that the price of the scum skimmer can be lowered. Meanwhile, the water collecting container 13 further includes a level sensor 23 installed at the intermediate portion thereof, the scum skimmer further includes a controller 24 provided between the level sensor 23 and the submersible pump 215 to receive the level of the water collecting container 13 from the level sensor 23 in real time and to control the suction force of the submersible pump 215. Thus, when the level sensor 23 detects the current water level in real time and the level is lowered, the controller 24 recognizes the lowered level and reduces the suction force of the submersible pump 215 to raise the level. On the contrary, when the level is raised, the controller 24 recognizes the raised level and increases the suction force of the submersible pump 215 to lower the level. Therefore, when skimming scum via the scum skimmer, a predetermined level of the water collecting container 13 can be maintained even if the level of the water collecting container 13 changes due to external factors such as waves so that the deterioration of scum skimming efficiency is prevented. Fig 8 is a perspective view illustrating a scum skimmer according to a second preferred embodiment of the present invention, and Fig. 9 is a sectional view taken along line C-C of Fig. 8. As shown in the drawings, the scum skimmer according to the second preferred embodiment of the present invention includes a main body 3 including a flotation device 35 for providing buoyancy to the main body 3, a water introduction passage 31 disposed around the outer circumference of the main body 3, a cave space having a closed outer circumference and disposed in the water introduction passage 31, and -a water collecting container 33 and a scum collecting container 34 respectively formed in the outer side and in the inner side of the cave space by partitioning the cave space via a partition 32, and a water collecting device 4 disposed in the water collecting container 33 to receive water and scum on the water surface through the water introduction passage 31 by generating a head of water under the water surface and to discharge the introduced water such that the introduced scum floats and is accumulated on the water surface, and overflows the partition 32 to be separated and skimmed in the scum collecting container 34. Particularly, the water collecting device 4 includes a scum discharging device 341 for compulsorily transporting the scum containing water in the scum collecting container 34 to land or to another ship. The scum discharging device 341 includes a discharge pump 342 disposed in the scum collecting container 34 to compulsorily transport the scum containing water to land or to another ship through a hose. Further, the water collecting device 4 includes a pumping device 41 disposed at the lower side of the water collecting container and generating a head of water to introduce water and scum on the water surface, and a drain 42 formed in the water collecting container to drain only water from the water and scum introduced into the water collecting container to the water. The pumping device 41 includes a submersible pump 415 disposed on the bottom of the water collecting container 33 to compulsorily discharge water introduced into the water collecting container 33 out of the water collecting container 33. Meanwhile, although not shown in the drawings, the water introduction passage 31 may be downwardly inclined from the outer side to the inner side thereof. Thus, since the water introduction passage 31 is downwardly inclined from the outer side to the inner side thereof, water and scum on the water surface are smoothly introduced into the water collecting container 33. Therefore, the scum collecting efficiency of the scum skimmer is enhanced when operating the scum skimmer according to the first preferred embodiment of the present invention. Hereinafter, the scum skimmer structured as described above according to the second preferred embodiment of the ' present invention will be described in detail in the following. As shown in Figs. 8 and 9, the drain 42 further includes a valve 422 for opening and closing the drain 42. Thus, when the scum skimmer according to the second preferred embodiment of the present invention is not operated, the valve 422 is closed to prevent the scum skimmer according to the second preferred embodiment of the present invention from sinking. Rotating rudders 423 are further installed at the outside of the drain 42 to adjust the moving direction and speed of the scum skimmer according to the second preferred embodiment of the present invention. In other words, the rudders 422 are rotatably installed to shafts protruded from the outside of the main body 3 by fixing devices and the direction and angle of the rudders 423 are easily adjusted by releasing and fixing the fixing devices. Meanwhile, the flotation device 35 includes protruding plates 351 protruded from the outer side of the water collecting container 33 and formed with through-holes 352, and floaters (not shown) or air tanks 153 installed to the upper sides of the protruding plates 351 to move up and down along long bolt shafts 355 and fixed by nuts to adjust the submersing level of the main body. Thus, according to the positions of the nuts fastened to the bolt shafts 355, the floating levels of the air tanks 353 are adjusted. Hereinafter, the operation of the scum skimmer according to the second preferred embodiment of the present invention will be described in the following. As shown in Figs. 8 and 9, a predetermined amount of air is injected into the air tanks 353 of the flotation device 35 through air injection holes 354 so as to adjust the floating level of the main body 3. Thus, the water introduction passage 31 provided at the front side of the main body 3 is submersed directly below the water surface. In addition, the nuts fastened to the bolt shafts 355 provided at the upper sides of the air tanks 353 are fastened or released so that the floating level of the air tanks 353 is adjusted. When the submersible pump 415 of the pumping device 41 provided in the water collecting container 33 is operated, water and scum on the water surface are introduced into the water collecting container 33 from the water introduction passage 31. Water is drained to the water through the drain 42 provided at the lower side of the water collecting container 33 and the scum is continuously accumulated on the upper side of the water collecting container 33. In other words, when the submersible pump 415 is operated, a force of introducing water on the^' water surface into the water collecting container 33 is generated at the lower side of the water collecting container 33. When the water is introduced into the water collecting container 33, due to a head of water, the water on the water surface flows into the water collecting container 33 through the water introduction passage 31. Thus, the level of the water collecting container 33 becomes lower than the level of the water surface, and the scum is continuously accumulated on the lowered water surface in the water collecting container 33. When the scum is continuously accumulated on the upper side of the water collecting container 33, the height of the accumulated scum becomes higher. Due to the increased height of the accumulated scum, the scum is skimmed into the scum collecting container 34. The scum collected in the scum collecting container 34 contains water. In addition, since the scum collecting container 34 includes a scum discharging pump 341 for discharging the collected scum, the scum discharging pump 342 easily transports the scum collected in a collecting tank 34 to another ship or to land such as riverside, or seashore so that the skimming of the scum can be continuously performed. Therefore, due to the structure and operation as described above, the objects of the present invention of receiving water and scum on the water surface using a head of water simultaneously and collecting and recovering only the floating scum and of collecting a great deal of scum in a short time can be achieved. In addition, since the water introduction passage 31 is disposed around the outer circumference of the upper side of the main body 1, water is introduced into the water collecting container 33 through any direction and scum is skimmed. Thus, the scum is more stably skimmed and the efficiency of skimming scum is maximized. Meanwhile, the water collecting container 33 further includes the level sensor 43 installed at the intermediate portion thereof, and the scum skimmer further includes a controller 44 connected to the level sensor 43 and the submersible pump 415 to receive the level of the water collecting container 13 from the level sensor 43 in real time and to control the suction force of the submersible pump 415. Thus, when the level sensor 43 detects the current water level in real time and the level is lowered, the controller 44 recognizes the lowered level and reduces the suction force of the submersible pump 415 to raise the level. On the contrary, when the level is raised, the controller 44 recognizes the raised level and increases the suction force of the submersible pump 415 to lower the level. Therefore, when skimming scum by the scum skimmer, a predetermined level of the water collecting container 33 can be maintained even if the level of the water collecting container 33 ^'changes due to external factors such as waves so that the deterioration of scum skimming efficiency is prevented. Fig. 10 is a perspective view illustrating another example of a scum skimmer according to the second preferred embodiment of the present invention, and Fig. 11 is a sectional view taken along the line D-D in Fig. 10. In the scum skimmer according to the second preferred embodiment of the present invention, the scum collecting container 34 further includes an inner girth plate 342 protruded from the water surface and having an opened central portion and is spaced apart from the lower side of the water collecting container 33, and the pumping device 41 includes a propeller 411 disposed at the central portion of the lower side of the water collecting container 33 and rotated by a motor 412 positioned above the water surface to move water down to generate a head of water. The pumping device 41 includes a horizontal partition

413 having an intermediate hole 414 for partitioning the lower side of the water collecting container 33 surrounding of the propeller 411 in the horizontal direction, and a water vortex prevention net 414a disposed in the upper side of the propeller 411, i.e. the upper side of the intermediate hole

414 to prevent water contained in the upper side of the horizontal partition 413 when the water is introduced into the intermediate hole 414 from rotating. In other words, since the water vortex net 414a is a net, the water vortex generated during the rotation of the propeller 411 is prevented. Thus, since the pumping device 41 includes the motor 412 and the propeller 411, a scum skimmer capable of processing a great deal of scum can be provided. Meanwhile, the water collecting container 33 further includes a level sensor 43 installed at the intermediate portion thereof, the scum skimmer further includes a controller 44 provided between the level sensor 43 and the motor 412 to receive the level of the water collecting container 33 from the level sensor 43 in real time and to control the rotation speed of the motor 412. Thus, when the level sensor 43 detects the current water level in real time and the level is lowered, the controller 44 recognizes the lowered level and reduces the rotation speed of the motor to raise the level. On the contrary, when the level is raised, the controller 44 recognizes the raised level and increases the rotation speed of the motor 412 to lower the level . Therefore, when skimming scum via the scum skimmer, a predetermined level of the water collecting container 33 can be maintained even if the level of the water collecting container 33 changes due to external factors such as waves so that the deterioration of scum skimming ^'efficiency is prevented. As described above, according to the scum skimmer of the present invention, water and scum are introduced due to a head of water and only scum is collected and skimmed so that the recovery of scum is maximized. Moreover, scum is collected using a head of water and by

'floating the sdum^" so that a great deal of scum can be collected and skimmed in a short time. Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims .

Claims

WHAT IS CLAIMED IS:

1. A scum skimmer comprising: a main body including: a flotation device for providing buoyancy to the main body; a water introduction passage disposed at the front side thereof; a cave space having an opened top and four closed sides and formed at the rear side of the water introduction passage; and a water collecting container and a scum collecting container respectively formed at the front and rear sides of the cave space by partitioning the cave space with a partition; and a water collecting device disposed in the water collecting container to receive water and scum on the water surface through the water introduction passage by generating a head of water under the water surface and to discharge the introduced water such that the introduced scum floats on the water surface to be accumulated and overflows the partition and is separated and skimmed into the scum collecting container.

2. The scum skimmer as set forth in claim 1, wherein the water introduction passage is downwardly inclined from the front side to the rear side thereof.

3. The scum skimmer as set forth in claim 1, further comprising a scum discharging device for compulsorily transporting the scum containing water in the scum collecting container to land or to another ship.

4. The scum skimmer as set forth in claim 3, wherein the scum discharging device comprises: a discharge pump disposed in the scum collecting container to compulsorily transport the scum containing water to land or to another ship.

5. The scum skimmer as set forth in claim 3, wherein the scum discharging device comprises a discharge pump disposed on land or a ship to compulsorily transport the scum contained in the scum collecting container and containing water to land or to another ship through a hose.

6. The scum skimmer as set forth in claim 1, wherein the water collecting device comprises: a pumping device disposed in the water collecting container to generate a head of water under the water surface such that the water and the scum are introduced into the water collecting container; and a drain formed in the water collecting container to drain only water from the water and scum introduced into the water collecting container to the water.

7. The scum skimmer as set forth in claim 6, wherein the pumping device comprises: a motor for generating a head of water; and a propeller driven by the motor

8. The scum skimmer as set forth in claim 7, wherein the pumping device comprises: a horizontal partition having an intermediate hole for partitioning the lower side of the water collecting container surrounding the propeller in the horizontal direction; and a water vortex prevention net disposed in the upper side of the propeller as the upper side of the intermediate hole to prevent water contained in the upper side of the horizontal partition when the water is introduced into the intermediate hole from rotating.

9. The scum skimmer as set forth in claims 7 or 8, wherein the water collecting container further comprises a level sensor installed at the intermediate portion thereof, and the scum skimmer further comprises a controller connected to the level sensor and the motor to receive the level of the water collecting container from the level sensor in real time and to control the -rotation speed of the motor.

10. The scum skimmer as set forth in claim 6, wherein the pumping device comprises a submersible pump disposed on the bottom of the water collecting container to compulsorily discharge water in the water collecting container through the drain.

11. The scum skimmer as set forth in claim 10, wherein the water collecting container further includes a level sensor installed at the intermediate portion thereof, and the scum skimmer further comprises a controller connected to the level sensor and the submersible pump to receive the level of the water collecting container from the level sensor in real time and to control the suction force of the submersible pump.

12. The scum skimmer as set forth in claim 6, wherein the drain further comprises a drainpipe for draining water to the water in front of the water introduction passage.

13. The scum skimmer as set forth in claim 6, further comprising rotating rudders installed at the outside of the drain to adjust the moving direction and speed of the scum skimmer.

14. The scum skimmer as set forth in claims 1 or 2, wherein the water introduction passage further comprises a pair of expanded passage guides installed at the front side of the water introduction passage to freely pivot about hinges, having a lower side kept submersed in water to a predetermined depth and a blocking plate or an oil fence disposed at the front sides thereof.

15. The scum skimmer as set forth in claim 14, wherein the water introduction passage further comprises a wave- breaking rotating body disposed at the front side of the expanded passage guides provided at the front side of the water introduction passage and including: a horizontal rotation shaft protruded from the front sides of the expanded passage guides; and a plurality of horizontal blades installed around the horizontal shaft.

16. The scum skimmer as set forth in claim 1, wherein the flotation device comprises: protruding plates protruded from lateral sides of the main body and formed with through-holes; and floaters or air tanks installed to the upper sides of the protruding plates to move up and down along long bolt shafts and fixed by nuts to adjust the submersion level of the main body.

17. A scum skimmer comprising: a main body including: a flotation device for providing buoyancy to the main body; a water introduction passage disposed around the outer circumference of the main body; a cave space having a closed outer circumference and disposed in the water introduction passage; and a water collecting container and a scum collecting container respectively formed in the outer side and in the inner side of the cave space by partitioning the cave space with a partition; and a water collecting device disposed in the water collecting container to receive water and scum on the water surface through the water introduction passage by generating a head of water under the water surface and to discharge the introduced water such that the introduced scum floats on the water surface to be accumulated and overflows the partition and is separated and skimmed in the scum collecting container.

18. The scum skimmer as set forth in claim 17, wherein the water introduction passage is downwardly inclined from the outer side to the inner side thereof.

19. The scum skimmer as set forth in claim 17, further comprising a scum discharging device for compulsorily transporting the scum containing water in the scum collecting container to land or to another ship.

20. The scum skimmer as set forth in claim 19, wherein the scum discharging device comprises a discharge pump disposed in the scum collecting container to compulsorily transport the scum containing water to land or to another ship through a hose.

21. The scum skimmer as set forth in claim 19, wherein the scum discharging device comprises a discharge pump disposed on land or in a ship to compulsorily transport the scum containing water to land or to another ship through a hose.

22. The scum skimmer as set forth in claim 17, wherein the water collecting device comprises: a pumping device disposed at the lower side of the water collecting container and generating a head of water to introduce water and scum on the water surface; and a drain formed in the water collecting container to drain only water from the water and scum introduced into the water collecting container to the water.

23. The scum skimmer as set forth in claim 22, wherein the pumping device comprises a submersible pump disposed on the bottom of the water collecting container to compulsorily discharge water introduced into the water collecting container from the water collecting container.

24. The scum skimmer as set forth in claim 23, wherein the water collecting container further comprises a level sensor installed at the intermediate portion thereof, and the scum skimmer further comprises a controller connected to the level sensor and the submersible pump to receive the level of the water collecting container from the level sensor in real time and to control the suction force of the submersible pump.

25. The scum skimmer as set forth in claim 22, wherein the scum collecting container further comprises an inner girth plate protruded from the water surface and having an opened central portion and spaced apart from the lower side of the water collecting container, and the pumping device comprises a propeller disposed at the central portion of the lower side of the water collecting container and rotated by a motor positioned above the water surface to move water down to generate a head of water.

26. The scum skimmer as set forth in claim 25, wherein the pumping device comprises: a horizontal partition having an intermediate hole for partitioning the lower side of the water collecting container surrounding the propeller in the horizontal direction; and a water vortex prevention net disposed in the upper side of the propeller as the upper side of the intermediate hole to prevent water contained in the upper side of the horizontal partition when the water is introduced into the intermediate hole from rotating.

27. The scum skimmer as set forth in claims 25 or 26, wherein the water collecting container further comprises a level sensor installed at the intermediate portion thereof, and the scum skimmer further comprises a controller connected to the level sensor and the motor to receive the level of the water collecting container from the level sensor in real time and to control the rotation speed of the motor.