JP5393065B2 - Levitation separator - Google Patents

Description

  The present invention relates to a technique of a levitation separation device that attaches bubbles to a substance to be treated in water to be treated and separates the substance to be treated as a floating substance.

  Conventionally, as a method of removing SS components, oils, and other substances to be treated contained in the water to be treated, the water to be treated and bubbles are mixed and supplied to the levitation tank. A levitation process is known that floats on the surface of a tank and separates a substance to be treated. In addition, in order to raise processing efficiency, before supplying to-be-processed water to a levitation tank, a flocculant is added and the to-be-processed substance contained in to-be-processed water is made to flock.

  FIG. 8 is a schematic diagram showing a configuration of a conventional floating separation apparatus. In the levitation separation device 4, the levitation tank 70 is provided with an inner peripheral wall 74, which has a lower end reaching the intermediate part in the tank, along the inner periphery of the outer peripheral wall 72, inside the outer peripheral wall 72 constituting the tank body. . The outer peripheral wall 72 and the inner peripheral wall 74 are cylindrical. Between the outer peripheral wall 72 and the inner peripheral wall 74, the inner peripheral wall 74 prevents a levitated material from entering, and a treated water chamber 76 in which treated water is collected is formed. A guide cylinder 78 having an open upper and lower part is provided in the central portion of the levitation tank 70. The guide cylinder 78 extends from the center of the bottom 70 a of the levitation tank 70, and is provided in the guide cylinder 78. An opening introducing pipe 80 is provided. A treated water inflow pipe 82 is connected to the introduction pipe 80 outside the floating tank 70. Further, a pressurized water inflow pipe 84 is connected to the treated water inflow pipe 82, and pressurized water in which air is dissolved under high pressure is supplied from here through a pressurized tank or the like.

  A method for operating the levitation separator 4 will be described. For example, pressurized water in which air is dissolved in the treated water under high pressure is supplied to the treated water inflow pipe 82 via the pressurized water inflow pipe 84, and a mixed liquid in which the pressurized water and the treated water are mixed passes through the treated water inflow pipe 82. As described above, the gas is supplied into the guide cylinder 78 of the levitation tank 70 through the introduction pipe 80. In the levitation tank 70, the gas dissolved in the pressurized water is precipitated as bubbles and adheres to the material to be treated contained in the water to be treated, and the material to be treated is floated and separated. The treated water from which the material to be treated has been removed passes from the lower end 76 a of the treated water chamber 76 through the treated water chamber 76, overflows the overflow weir at the upper end of the outer peripheral wall 72 of the floating tank 70, and is supplied to the adjusting tank 86. The treated water discharge pipe 88 connected here discharges the outside of the system.

  Here, in the levitation separation device 4 shown in FIG. 8, the water to be treated that flows into the levitation tank 70 through the introduction pipe 80 and the guide cylinder 78 flows toward the inner peripheral wall 74 of the levitation tank 70, and the inner peripheral wall 74. , It descends along the inner peripheral wall 74. When the flow rate of the downward flow is high, the material to be treated having insufficient buoyancy flows into the treated water chamber 76 over the lower end of the inner peripheral wall 74 along with the downward flow, thereby deteriorating the quality of the treated water. Thus, the reason why the downward flow along the inner peripheral wall 74 becomes faster is because there are many portions (for example, the shaded portions shown in FIG. 8) that are not used for the floating separation process in the floating tank 70. In the removal of the material to be treated, there is a problem that the floating separation cannot be performed efficiently unless the entire floating tank 70 can be used effectively.

  The general water area load (the amount of treated water (linear velocity LV) with respect to the horizontal sectional area of the levitation tank 70) of the levitation separator 4 shown in FIG. 8 is 5 to 10 m / h. In the levitation separator 4 shown in FIG. 8, when the LV is higher than the above range, the quality of the treated water tends to deteriorate.

  Further, Patent Document 1 proposes a levitation separator that can increase the LV compared to the levitation separator 4 shown in FIG. FIG. 9 is a schematic diagram showing the configuration of the flotation separation device of Patent Document 1. As shown in FIG. In the levitation separator 5 shown in FIG. 9, the peripheral wall 90a of the levitation tank 90 is rectangular, and in the levitation tank 90, water to be treated is detoured in the vertical direction by the upper open partition 92a and the lower open partition 92b. It is divided into three chambers that flow, a first chamber 94, a second chamber 96, and a third chamber 98. A rectifying plate 100 is horizontally installed between the partition wall 92a and the partition wall 92b of the second chamber 96. A plurality of rectifying holes 100 a are formed in the rectifying plate 100, and water from the second chamber 96 to the third chamber 98 passes through the rectifying plate 100. The first chamber 94 is connected to the treated water inflow pipe 102. One end of the pressurized water inflow pipe 104 is connected to the first chamber 94, and the other end is connected to the outlet of the air dissolution tank 105. A treated water discharge pipe 106 is connected to the third chamber 98. A communication pipe 111 is connected between the air dissolution tank 105 and the treatment discharge pipe 106 via a pump 110, and part of the treated water passing through the treatment water discharge pipe 106 passes through the communication pipe 111, and the air dissolution tank 105. To be supplied. In the air dissolution tank 105, air is dissolved in the treated water to produce pressurized water.

  In such a levitation separation device 5, the water to be treated that has flowed into the first chamber 94 from the water to be treated inflow pipe 102, and the pressurized water that has flowed into the first chamber 94 from the air dissolution tank 105 through the pressurized water inflow pipe 104 are liquid. It rises toward the surface and flows into the adjacent second chamber 96. In the second chamber 96, the substance to be treated in the water to be treated floats on the liquid surface as a floating substance, and treated water is obtained at the bottom. The treated water that has been subjected to such a floating separation process passes through the rectifying hole 100 a of the rectifying plate 100 and is discharged from the third chamber 98 to the treated water discharge pipe 106.

  Also in the levitation separation apparatus 5 shown in FIG. 9, the flow rate of the downflow of the water to be treated that descends along the partition wall 92b of the second chamber 96 is increased. However, since the levitation separation device 5 shown in FIG. 9 is provided with the rectifying plate 100, due to the rectifying effect of the rectifying plate 100, the downward flow of the water to be treated descending along the partition wall 92b remains as it is, The flow to the third chamber 98 side is prevented. As a result, the material to be treated is prevented from flowing into the third chamber 98 side along with the downward flow, and the levitating separation device 5 shown in FIG. 9 can be processed at a higher volume load than the levitating separation device 4 shown in FIG. It becomes possible.

US Patent Application Publication No. 2005/0115881

  In the levitation separation apparatus 5 shown in FIG. 9, the peripheral wall 90a of the levitation tank 90 is rectangular, the water to be treated is supplied from the first chamber 94 provided on one end side of the peripheral wall 90a, and the first is provided on the other end side. 3, the treated water is discharged from the third chamber 98. In such a structure, the flow of the water to be treated flowing from the first chamber 94 to the partition wall 92b (that is, the flow of the water to be treated flowing on the liquid surface of the levitation tank) is a guide cylinder in the levitation separation apparatus shown in FIG. The flow rate becomes faster than the flow of the water to be treated flowing from 78 to the inner peripheral wall 74 (that is, the flow of the water to be treated flowing on the liquid surface of the levitation tank).

  Further, when the load of the floating separation device is increased, the flow rate of the water to be treated flowing on the liquid surface of the floating tank 90 is further increased, and the flow rate of the descending flow descending along the partition wall 92b is also increased. As a result, a downward flow having a high flow velocity collides with the rectifying plate 100 on the side of the partition wall 92b, and it becomes difficult to sufficiently obtain the rectifying effect of the rectifying plate 100. It cannot suppress sufficiently that it flows into 98 side, etc., and the quality of treated water tends to deteriorate. Therefore, even in the floating separation apparatus 5 as shown in FIG. 9, it is necessary to enlarge the apparatus in order to increase the throughput without deteriorating the quality of the treated water.

  Accordingly, an object of the present invention is to provide a floating separation apparatus capable of high-speed processing with a small apparatus.

  The present invention is a levitation separator that attaches bubbles to a substance to be treated in water to be treated and separates the substance to be treated as a floating substance, and rectifies the levitation tank and the levitation tank into a vertical upper part and a lower part A plate, an inflow portion for allowing treated water to flow into the upper portion, and a water collecting portion that is provided in the floating tank and collects treated water separated from the treated material from the lower portion, Are formed with a plurality of rectifying holes for allowing the treated water to flow therethrough, and the inflow portion is opened at the center of the upper portion, and the treated water is caused to flow into the upper portion from the opening.

  In the levitation separation apparatus, the levitation tank is preferably cylindrical.

  Further, in the flotation separation apparatus, a levitated skimmer that rakes the levitated matter floating on the liquid level of the levitation tank, and a deposit raker that rakes the deposit that has settled at the bottom of the levitating tank among the substances to be treated. And preferably.

  Moreover, it is preferable that the levitation separation apparatus further includes a rectifying plate scraper that discharges the sediment that has settled on the rectifying plate out of the material to be treated into the rectifying holes.

  In the floating separation apparatus of the present invention, high-speed processing is possible with small equipment.

  Embodiments of the present invention will be described below. This embodiment is an example for carrying out the present invention, and the present invention is not limited to this embodiment.

  FIG. 1 is a schematic cross-sectional view showing an example of the configuration of the levitation separation apparatus according to the present embodiment. FIG. 2 is a schematic top view showing an example of the configuration of the levitation separation apparatus according to the present embodiment. The levitation separation device 1 shown in FIG. 1 includes a levitation tank 10, an inflow portion 12, a discharge portion 14, and a rectifying plate 22.

  As shown in FIGS. 1 and 2, the peripheral wall 10a of the levitation tank 10 has a cylindrical shape, and the bottom 10b of the levitation tank 10 has a hopper shape that becomes lower toward the center. A pit 18 is provided at the center of the bottom portion 10b to collect a deposit of the material to be treated. The pit 18 is provided with a sediment discharge port (not shown), and a sediment discharge pipe 19 is connected thereto. The peripheral wall 10a of the floating tank 10 may be rectangular. However, by forming the peripheral wall 10a of the levitation tank 10 into a cylindrical shape, the water to be treated spreads from the opening portion (the opening portion will be described later) of the inflow portion 12 disposed at the center of the levitation tank 10 to the peripheral wall 10a. It will flow while. Therefore, although the flow velocity when exiting the inflow portion 12 is relatively fast, the flow of the surface portion when hitting the peripheral wall 10a is relatively slow. As a result, a rapid downward flow does not occur in a part of the peripheral wall 10a, and the deterioration of the quality of the treated water caused by the rapid downward flow can be effectively suppressed.

  The floating tank 10 is provided with a water collecting part 10c. The water collecting part 10c collects treated water from which the material to be treated has been removed from the lower part 20b of the floating tank 10, which will be described later, and is disposed on the lower part 20b side of the floating tank 10, that is, below the current plate 22 in the vertical direction. The

  The levitation tank 10 is provided with a levitation object pot 24 for discharging the levitation material 23 (so-called scum) that has floated on the liquid surface among the substances to be treated. In a normal case, a skimmer is provided on the surface of the levitation tank 10 to scrape the levitated matter, and the levitated matter is raked up to the levitated pot 24. The levitated pot 24 has a slope extending from below the surface of the water to the surface of the water so that the levitated object that is raked down falls into the levitated object pot 24 from the surface of the water. Is preferred.

  A rectifying plate 22 is provided in the levitation tank 10 to divide the levitation tank 10 into an upper part 20a and a lower part 20b in the vertical direction. And the baffle plate 22 is formed with a plurality of baffle holes 22a through which the treated water flows. The rectifying plate 22 may have an integral structure or may be divided into a plurality of parts.

  FIG. 3 is a schematic top view showing an example of the configuration of a levitation separation apparatus according to another embodiment of the present invention. As shown in FIG. 3, a rectifying plate 22 that divides the floating tank 10 into an upper part 20 a and a lower part 20 b is formed by four fan-shaped divided bodies 25. The number of the fan-shaped divided bodies 25 is not particularly limited. The function of the current plate 22 will be described later.

  The inflow portion 12 includes a guide tube 26 and an introduction pipe 28 provided in the guide tube 26. A treated water inflow pipe 30 is connected to the introduction pipe 28, and the introduction pipe 28 extends from the pit 18 formed in the center of the bottom 10 b of the levitation tank 10 into the levitation tank 10. A pressurized water inflow pipe 32 is connected to the treated water inflow pipe 30. The guide tube 26 provided in the floating tank 10 is fixed to the bottom 10b and the peripheral wall 10a with a frame or the like. The guide tube 26 may be suspended from above. By providing the guide tube 26, the water to be treated and the pressurized water supplied from the introduction pipe 28 can be uniformly introduced from the central portion of the levitation tank 10.

  The inflow part 12 of this embodiment is opened at the center of the upper part 20a of the levitation tank 10, and the treated water (mixed with pressurized water) is supplied from the opening to the upper part 20a of the levitation tank 10. Here, when the inflow part 12 is comprised from the guide cylinder 26 and the inlet tube 28 like this embodiment, the opening part 26a of the guide cylinder 26 should just open in the center part of the upper part 20a. The inflow portion 12 of this embodiment does not necessarily need to include the guide tube 26. For example, the inflow portion 12 may be composed only of the introduction pipe 28. In this case, the opening 28a of the introduction pipe 28 needs to open at the center of the upper portion 20a. In any case, the water to be treated needs to flow into the central portion of the upper portion 20a of the floating tank 10. It is preferable to flow into a region within 1/3 from the center with respect to the distance from the center to the peripheral wall 10a in the horizontal section of the upper portion 20a of the levitation tank 10.

  The position of the opening portion of the inflow portion 12 (in FIG. 1, the opening portion 26a of the guide tube 26) is not particularly limited as long as it is vertically above the upper portion 20a of the levitation tank 10, that is, the rectifying plate 22. However, if the position of the opening of the inflow portion 12 is near the liquid level, the water to be treated supplied from the opening of the inflow portion 12 spouts up to the liquid surface, disturbs the liquid surface, and floats to the liquid surface. There is a risk of re-sedimentation of the object 23.

  FIG. 4 is a partially enlarged schematic cross-sectional view of the levitation separator according to this embodiment. The guide cylinder 26 is inserted into a fitting insertion hole provided in the rectifying plate 22. When a gap is formed between the insertion hole of the rectifying plate 22 and the guide tube 26, a water stop plate that blocks the gap so that the water to be treated flows from the gap and the quality of the treated water is not deteriorated. 34 is preferably provided. The water stop plate 34 is fixed to the current plate 22 by fasteners 36 such as bolts and nuts. The introduction tube 28 is inserted into a fitting insertion hole provided in the guide tube 26. When a gap is formed between the insertion hole of the guide tube 26 and the introduction pipe 28, it is preferable to provide a water stop plate 34 that closes the gap as described above. The water stop plate 34 is fixed to the guide tube 26 by fasteners 36 such as bolts and nuts. It is also preferable to provide a flange on the outer periphery of the guide tube 26 and fix the end of the rectifying plate 22 to this flange.

  The discharge unit 14 includes a treated water extraction pipe 38, a water level adjustment tank 40, and a treated water discharge pipe 42. One end of the treated water outlet pipe 38 is connected to a water collecting part 10 c provided in the floating tank 10, and the other end of the treated water outlet pipe 38 is connected to the inlet of the water level adjusting tank 40. A treated water discharge pipe 42 is connected to the outlet of the water level adjustment tank 40.

  Next, an example of the operation method by the levitation separator according to the present embodiment will be described. First, the water to be treated is caused to flow from the water to be treated inflow pipe 30 and the pressurized water in which the gas is dissolved from the pressure water inflow pipe 32 under high pressure. Pressurized water is generated by introducing a portion of treated water into a pressurized tank, where air is dissolved under high pressure.

  The pressurized water that passes through the pressurized water inflow pipe 32 is mixed with the treated water that passes through the treated water inflow pipe 30. A mixed liquid composed of water to be treated and pressurized water is supplied from the water to be treated inflow pipe 30 to the introduction pipe 28. The water to be treated and the pressurized water are supplied into the guide tube 26 from the opening 28 a of the introduction pipe 28 through the introduction pipe 28. Water to be treated and pressurized water supplied into the guide cylinder 26 (rising toward the liquid level of the levitation tank 10) flow into the upper part 20 a of the levitation tank 10 from the opening 26 a of the guide cylinder 26. Since the upper part 20a of the levitation tank 10 (and the inside of the guide cylinder 26) is in an atmospheric pressure state, the gas dissolved in the pressurized water is precipitated as bubbles, and becomes a substance to be treated (SS component, oil, etc.) in the treated water. It adheres and the material to be treated floats and is separated. The material to be treated (the levitated material 23) that has floated in this manner is collected in the levitated material pot 24. The collection of the floating object 23 is normally performed by a floating object skimmer described later, but may be performed by other methods. The float 23 collected in the float pot 24 is discharged from the float discharge pipe 44 connected to the discharge port of the float pot 24. The method of generating bubbles is not limited to the method using pressurized water as described above, but may be a method of adding a bubble generating agent such as a surfactant to the water to be treated. . Alternatively, a whole-pressure method may be employed in which the water to be treated itself is introduced into an air dissolution tank and air is directly dissolved in the water to be treated.

  When the water to be treated supplied from the opening 26a of the guide tube 26 to the upper portion 20a of the levitation tank 10 reaches the peripheral wall 10a of the levitation tank 10, a downward flow flows along the peripheral wall 10a. Therefore, in the present embodiment, it is preferable that the opening 26a of the guide cylinder 26 opens vertically upward at the center of the upper portion 20a of the levitation tank 10, and the peripheral wall 10a of the levitation tank 10 is cylindrical. With the above configuration, the water to be treated becomes a dispersed flow that spreads radially and reaches the peripheral wall 10a of the levitation tank 10 as shown in FIG. As a result, the flow of the water to be treated supplied from the opening 26a becomes gentle before reaching the peripheral wall 10a of the levitation tank 10, and the downward flow of the water to be treated flowing along the peripheral wall 10a also becomes gentle. Therefore, deterioration of the quality of the treated water caused by the rapid downward flow is suppressed.

  Here, the shape of the opening of the inflow portion 12 (in FIG. 1, the opening 26a of the guide tube 26) is not particularly limited, but the water to be treated supplied from the opening of the inflow portion 12 is dispersed radially. From the viewpoint of facilitating this, it is preferable that the upper portion of the upper portion spreads in a tapered shape. In addition, the horizontal cross-sectional area of the opening of the inflow portion 12 is not particularly limited, but it is preferable that the flow rate of the water to be treated flowing through the inflow portion 12 can be appropriately controlled. It is good to set it as the range of 1/20 to 1/8 of the horizontal cross-sectional area of the horizontal cross-sectional area of the horizontal cross-sectional area of the horizontal tank of the floating tank 10, More preferably. If the horizontal cross-sectional area of the opening of the inflow portion 12 is smaller than 1/30 of the horizontal cross-sectional area of the levitation tank 10, the flow rate of the water to be treated when exiting the inflow portion 12 is increased. The flow rate of the water to be treated flowing from the opening toward the peripheral wall 10a of the levitation tank 10 is increased, the liquid surface of the levitation tank 10 is likely to be disturbed, and the floating object 23 that has floated to the liquid surface is regenerated. There is a risk of causing sedimentation. Moreover, since the downflow of the to-be-processed water which flows along the surrounding wall 10a of the levitation tank 10 also becomes fast, the whole rectification | straightening board 22 cannot be used effectively, the rectification | straightening effect reduces and the quality of treated water is reduced. It can get worse. Moreover, when the horizontal cross-sectional area of the opening part of the inflow part 12 is larger than 1/3 of the horizontal cross-sectional area of the levitation tank 10, it becomes difficult to ensure the area of the levitation tank 10, and the water area load of the levitation tank 10 is large. Therefore, efficient levitation processing cannot be performed.

  In the upper part 20 a of the levitation tank 10, the treated water from which the substance to be treated has been removed passes through the rectifying holes 22 a provided in the rectifying plate 22 and is supplied to the lower part 20 b of the levitation tank 10. By providing the rectifying plate 22, the flow of the treated water flowing from the upper part 20a to the lower part 20b is rectified, so that the downward flow of the treated water flowing along the peripheral wall 10a is prevented from flowing to the lower part 20b at the same flow rate. Is done. That is, the flow rate of the treated water flowing from the upper part 20a to the lower part 20b is made almost uniform everywhere due to the rectifying effect of the rectifying plate 22. As a result, the entire upper part 20a of the levitation tank 10 can be used for the levitation separation process, and bubbles can be efficiently attached to the material to be treated, so that the processing capacity can be improved. In addition, a material to be treated (precipitate) having a high specific gravity that cannot float even if bubbles are attached, or a material to be treated to which bubbles are not sufficiently adhered are locally deposited on the bottom 10b below the peripheral wall 10a. It settles in the whole bottom part 10b. Thus, since the entire levitation tank 10 can be used effectively in the removal of the substance to be treated, the apparatus can be downsized and the levitation separation tank apparatus can be processed at high speed.

  The treated water supplied to the lower portion 20b of the levitation tank 10 through the rectifying holes 22a formed in the rectifying plate 22 passes from the water collection section 10c of the levitation tank 10 through the treated water extraction pipe 38 to the water level adjustment tank 40. Supplied. A movable weir 41 is provided in the water level adjustment tank 40. By adjusting the height of the movable weir 41, the water level in the levitation tank 10 can be adjusted, and the water level in the levitation tank 10 is adjusted to a water level suitable for discharging the float 23 to the float pot 24. Then, the treated water is discharged from the outlet of the water level adjustment tank 40 to the treated water discharge pipe 42. In addition, it is also possible to raise the movable weir 41 intermittently and thereby overflow the floating material 23 in the floating tank 10 to the floating material pot 24.

  FIG. 5 is a schematic cross-sectional view showing an example of the configuration of a flotation separation apparatus according to another embodiment of the present invention. As shown in FIG. 5, the levitation separation device 2 includes a levitation tank 46, an inflow portion 12, a discharge portion 54, and a rectifying plate 22. In the floating separation apparatus 2 shown in FIG. 5, the same reference numerals are given to the same components as those in the floating separation apparatus 1 shown in FIG.

  The floating tank 46 is provided with an outer peripheral wall 48 and an inner peripheral wall 50 formed along the inner periphery of the outer peripheral wall 48. As described above, the outer peripheral wall 48 and the inner peripheral wall 50 of the levitation tank 46 are preferably cylindrical rather than rectangular. The bottom 46a of the levitation tank 46 has a hopper shape that becomes lower toward the center. A pit 18 for collecting sediment is provided at the center of the bottom 46a of the levitation tank 46.

  A treated water chamber 52 for collecting treated water is formed between the outer peripheral wall 48 and the inner peripheral wall 50 of the levitation tank 46. The water collecting part 52a of the treated water chamber 52 is vertically below the rectifying plate 22 in order to collect treated water from the lower part 20b of the floating tank 46 partitioned by the rectifying plate 22. Placed in.

  In the levitation tank 46, a rectifying plate 22 is provided that divides the levitation tank 46 into an upper part 20a and a lower part 20b in the vertical direction. And the baffle plate 22 is formed with a plurality of baffle holes 22a through which the treated water flows. The inflow portion 12 includes a guide tube 26 and an introduction pipe 28 provided in the guide tube 26. A treated water inflow pipe 30 is connected to the introduction pipe 28, and the introduction pipe 28 extends into the levitation tank 10 from a pit 18 formed at the center of the bottom 46 a of the levitation tank 46. A pressurized water inflow pipe 32 is connected to the treated water inflow pipe 30. The guide cylinder 26 provided in the levitation tank 46 is fixed in the levitation tank 46 from the outside of the apparatus by a frame (not shown) or the like. In the present embodiment, the inflow portion 12 is opened upward in the vertical direction at the center of the upper portion 20a of the levitation tank 46, and the water to be treated is supplied from the opening to the upper portion 20a of the levitation tank 46.

  The discharge unit 54 includes an adjustment tank 56 and a treated water discharge pipe 58. The adjustment tank 56 is installed on the outer periphery of the outer peripheral wall 48 of the levitation tank 46, and a treated water discharge pipe 58 is connected to the outlet of the adjustment tank 56.

  Next, an example of the operation method by the levitation separator 2 according to the present embodiment will be described. First, the water to be treated is caused to flow from the water to be treated inflow pipe 30 and the pressurized water is caused to flow from the pressure water inflow pipe 32. The pressurized water that passes through the pressurized water inflow pipe 32 is supplied to the treated water that passes through the treated water inflow pipe 30. The treated water and the pressurized water pass through the treated water inflow pipe 30 and are supplied to the introduction pipe 28. The water to be treated and the pressurized water pass through the introduction pipe 28 and are supplied into the guide tube 26 from the opening 28 a of the introduction pipe 28. Water to be treated and pressurized water passing through the guide cylinder 26 (rising toward the liquid level of the levitation tank 46) are supplied from the opening 26a of the guide cylinder 26 to the upper portion 20a of the levitation tank 46. In the present embodiment, since the opening 26a of the guide tube 26 opens vertically upward at the center of the upper portion 20a of the levitation tank 46, the water to be treated becomes a flow that is radially dispersed, and the levitation tank 46 Reaches the inner peripheral wall 50 of. In the upper part 20a of the levitation tank 46 (and in the guide cylinder 26), the pressurized water is in an atmospheric pressure state, and the gas dissolved in the pressurized water is precipitated as bubbles, so that the substance to be treated (SS component, oil content, etc.) in the treated water The material to be treated is floated and separated. The levitated material 23 that has been levitated and separated is collected in a levitated material pot (not shown) provided in the levitating tank 46. The collection of the levitated object 23 is normally performed by a levitated skimmer described later, but may be performed by other methods. The floating material 23 collected in the floating material pot is discharged from a floating material discharge pipe (not shown) connected to the discharge port of the floating material pot.

  In the upper part 20 a of the levitation tank 46, the treated water from which the substance to be treated has been removed passes through the rectifying holes 22 a provided in the rectifying plate 22 and is supplied to the lower part 20 b of the levitation tank 46. By providing the rectifying plate 22, the flow of treated water flowing from the upper part 20a to the lower part 20b is rectified. The treated water supplied to the lower portion 20b of the levitation tank 46 through the rectifying hole 22a formed in the rectifying plate 22 passes through the treated water chamber 52 from the water collecting portion 52a of the levitation tank 46, and the outer peripheral wall of the levitation tank 46. 48 is overflowed and supplied to the adjustment tank 56. The treated water supplied to the adjustment tank 56 is discharged from the outlet of the adjustment tank 56 to the treated water discharge pipe 58.

  Even in such a configuration, the entire levitation tank can be effectively used in removing the material to be treated by using the cylindrical levitation tank 10 and the rectifying plate 22 that vertically partitions the inside of the levitation tank. And high-speed processing of the floating separation tank apparatus are possible.

  FIG. 6 is a schematic cross-sectional view showing an example of the configuration of a levitation separator according to another embodiment of the present invention. The floating separation device 3 shown in FIG. 6 is obtained by providing the floating separation device 1 shown in FIG. 1 with a floating material skimmer 60, a sediment scraper 62, and a current plate scraper 64. In the levitation separator 3 shown in FIG. 6, the same components as those of the levitation separator 1 shown in FIG.

  The levitated skimmer 60 is for scraping the levitated matter 23 that has levitated to the liquid surface. The levitated skimmer 60 is fixed to the shaft of the motor 66. When the motor 66 is driven, the levitated skimmer 60 is rotated, and the levitated matter that has levitated to the liquid surface is scraped. The levitated skimmer 60 has scraper portions such as blades and spiral vanes, and the levitated matter 23 is moved radially outward by the flow of the water surface and the movement of the scraper portion, and the levitated matter provided in the levitating tank 10. They are collected in the pot 24 and discharged from the floating material discharge pipe 44. By providing the levitated skimmer 60, the levitated material 23 can be efficiently discharged, so that deterioration of the quality of the treated water can be suppressed.

  The sediment scraper 62 is for scraping the sediment deposited on the bottom 10 b of the floating tank 10. The sediment scraper 62 is attached to the guide tube 26, and the angle of the sediment scraper 62 is reinforced by a support 68. The guide cylinder 26 is attached to the shaft of the motor 66 and is rotated by driving of the motor 66. That is, the sediment scraper 62 is rotated integrally with the guide cylinder 26 by the drive of the motor 66. As the sediment scraper 62 rotates, the sediment deposited on the bottom 10 b of the floating tank 10 is scraped, collected in the pit 18 of the floating tank 10, and discharged from the sediment discharge pipe 19. In addition, this sediment scraper 62 also has scraper parts, such as a blade | wing and a spiral blade, and scrapes a sediment inward by this scraper part.

  Here, in the past, regular maintenance was required to clean the sediment. However, by providing the sediment scraper 62, the sediment can be efficiently discharged, so the number of maintenance times is reduced. The system can be operated continuously for a long time.

  The rectifying plate scraper 64 scrapes the sediment that has settled on the rectifying plate 22 and drops it downward from the rectifying holes 22a of the rectifying plate 22 to discharge it. The rectifying plate scraper 64 is attached to the guide cylinder 26, and is rotated integrally with the guide cylinder 26 by driving of the motor 66. As the rectifying plate scraper 64 rotates, the sediment deposited on the rectifying plate 22 is scraped off, and the precipitate is discharged from the rectifying holes 22 a of the rectifying plate 22. By providing the rectifying plate scraper 64, the number of times of maintenance for cleaning the rectifying plate 22 is reduced, and long-term continuous operation of the apparatus becomes possible. The baffle scraper 64 also has blades or the like, but the blades do not have to transport sediment in the radial direction. However, since it is preferable to transport the precipitate in a direction far from the water collection portion 10c of the treated water, it is preferable to use a blade that scrapes the precipitate inward.

  Note that the rotational speeds of the levitated skimmer 60, the sediment scraper 62, and the current plate scraper 64 are not the same, and may be different from each other. However, if the rotation speed is the same, a speed reduction mechanism or the like is unnecessary, and the drive mechanism can be simplified. In particular, it is preferable to set the blade inclination to an appropriate value according to the object.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated in detail more concretely, this invention is not limited to a following example.

Example 1
Using the floatation separation apparatus with the floatation skimmer 60 of FIG. 6 attached to the floatation separation apparatus 1 of FIG. 1, the surface separation of the treated water is performed under the following conditions, and the turbidity of the treated water after the floatation separation is measured. did. The water to be treated supplied to the levitation separator was previously agglomerated in a flocculation tank (size: 3000 L, 1600 mmΦ × height 2000 mm).
<Floating separator size>
Levitation tank: 1600mmΦ
Guide tube: 300mmΦ
<Test conditions>
Water to be treated: Toda City industrial water added with 10 mg / L of kaolin and 1 mg / L of humin Water to be treated Turbidity: 8.7 degrees Flocculant used during agglomeration treatment: Polyaluminum chloride (PAC) 30 mg / L L addition Water to be treated at the time of aggregation pH: 7 (addition of HCl and NaOH as pH adjusters)
Processed water flow rate: 50 m ³ / hr
Pressurized water ratio: 20%
Water flow rate: 30.9m / h
Float skimmer speed: 2 minutes / lap Test time: 14 days continuous operation

(Example 2)
The test was performed under the same conditions as in Example 1 except that the levitating separation apparatus 1 of FIG. 1 was equipped with the levitating skimmer 60 and the current plate scraper 64 of FIG. The speed of the current plate scraper 64 was 2 minutes / circumference.

(Example 3)
A test was performed under the same conditions as in Example 1 using the floating separator 3 of FIG. 6 (that is, the float skimmer 60, the current plate scraper 64, and the sediment scraper 62). The sediment accumulated in the 10 pits 18 was extracted from the sediment discharge pipe 19 once every 2 hours. Moreover, the speed of the baffle scraper 64 and the speed of the sediment scraper 62 were each 2 minutes / circumference.

  FIG. 7 is a diagram illustrating the results of treated water turbidity in Examples 1 to 3. As shown in FIG. 7, the turbidity of the treated water averaged 2 degrees or less on average, except for the value of the 10th day of continuous operation, when using the floating separator with the floating skimmer 60 attached thereto in Example 1. became. Since the turbidity of the water to be treated is 8.7 degrees on average, it can be determined that it is sufficient as a floating separation process for the water to be treated. The reason why the treated water turbidity increased on the 10th day of continuous operation is that the sediment precipitated on the rectifying plate 22 and the bottom portion 10b of the levitation tank 10 flowed into the water collecting portion 10c all at once.

  The turbidity of the treated water could be reduced as compared with Example 1 when Example 2 was used, that is, when the levitating separator equipped with the levitated skimmer 60 and the current plate scraper 64 was used. Furthermore, it was found that even in continuous operation for 14 days, the turbidity of the treated water does not increase rapidly and stable treatment is possible. This is a result of the sediment being prevented from being deposited on the rectifying plate 22 by the rectifying plate scraper 64, so that the sediment is prevented from being discharged from the floating tank 10 together with the treated water.

  When the floating separator equipped with the float skimmer 60, the baffle scraper 64, and the sediment scraper 62 was used in Example 3, the turbidity of the treated water could be reduced as compared with Example 2. This is because the sediment deposited on the rectifying plate 22 and the bottom portion 10b of the levitation tank 10 is scraped by the rectifying plate scraper 64 and the sediment scraper 62 and discharged from the sediment discharge pipe 19, so that the sediment is treated. It is the result that it was further controlled that it was discharged from floating tank 10 with water.

It is a schematic cross section which shows an example of a structure of the floating separation apparatus which concerns on this embodiment. It is a model top view which shows an example of a structure of the floating separation apparatus which concerns on this embodiment. It is an upper surface schematic diagram which shows an example of a structure of the floating separation apparatus which concerns on other embodiment of this invention. It is a partially expanded schematic cross section which shows an example of a structure of the floating separation apparatus which concerns on embodiment of this invention. It is a schematic cross section which shows an example of a structure of the floating separation apparatus which concerns on other embodiment of this invention. It is a schematic cross section which shows an example of a structure of the floating separation apparatus which concerns on other embodiment of this invention. It is a figure showing the result of the treated water turbidity in Examples 1-3. It is a schematic diagram which shows the structure of the conventional floating separation apparatus. It is a schematic diagram which shows the structure of the floating separation apparatus of patent document 1.

Explanation of symbols

  1-5 Floating separation device 10, 46, 70, 90 Floating tank, 10a, 90a Perimeter wall, 10b, 46a, 70a Bottom, 10c, 52a Water collecting part, 12 Inflow part, 14, 54 Discharge part, 18 pits, 19 Precipitate discharge pipe, 20a upper part, 20b lower part, 22,100 rectifying plate, 22a, 100a rectifying hole, 23 levitated object, 24 levitated substance pot, 25 fan-shaped divided body, 26, 78 guide tube, 26a opening, 28 , 80 Introducing pipe, 28a opening, 30, 82, 102 treated water inflow pipe, 32, 84, 104 pressurized water inflow pipe, 34 water stop plate, 36 fastener, 38 treated water outlet pipe, 40 water level adjusting tank, 41 movable Weir, 42, 58, 88, 106 Treated water discharge pipe, 44 Floating matter discharge pipe, 48, 72 Outer peripheral wall, 50, 74 Inner peripheral wall, 52, 76 Treated water chamber, 56, 86 Tank, 60 Levitated skimmer, 62 Sediment scraper, 64 Rectifier scraper, 66 Motor, 68 Support, 76a Lower end, 92a, 92b Bulkhead, 94 First chamber, 96 Second chamber, 98 Third Chamber, 105 air dissolution tank, 110 pump, 111 communication pipe.

Claims (3)

A levitation separation device that attaches bubbles to a substance to be treated in the water to be treated and separates the substance to be treated as a floating substance,
A cylindrical levitation tank, a rectifying plate that divides the levitation tank into an upper part and a lower part in the vertical direction, an inflow part for allowing water to be treated to flow into the upper part, and the levitation tank are provided to separate the substance to be treated. And a water collection part for collecting the treated water from the lower part,
The rectifying plate is formed with a plurality of rectifying holes for allowing the treated water to flow therethrough,
The inlet portion is opened in the center of the upper, and the guide tube from the opening Ru allowed to flow into the water to be treated to the upper, the inlet pipe for introducing into the guide tube the treatment water upflow Have
The horizontal separation area of the opening is in the range of 1/30 to 1/3 of the horizontal sectional area of the levitation tank. It is a floatation separation apparatus of Claim 1, Comprising: The float skimmer which scrapes the float which floated on the liquid level of the said float tank, and the deposit which settled to the bottom part of the float tank of the said to-be-processed substance is scraped A flotation separator comprising: a sediment scraper; The levitation separation apparatus according to claim 1 or 2 , further comprising a rectifying plate scraper that discharges sediments deposited on the rectifying plate out of the material to be treated downward from the rectifying holes. Separation device.

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