JP2006200502A - Foreign matter discharge method and foreign matter discharge device for pumping well - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a foreign matter discharge method and a foreign matter discharge device for a pumping well using a drain pump at the time of stopping of pump drain operation after water increase caused by rain. <P>SOLUTION: At the time of stopping of pump drain operation, a delivery valve 9 of the drain pump 2 is closed in the state that the water level is maintained to be equal to or higher than a lowermost operation water level LLWL, delivery water of the drain pump 2 is force-fed to a nozzle pipe 12 of the pumping swell 1, the delivery water is injected to the pumping well 1 and the foreign matter is stirred, and after that, the delivery valve 9 of the drain pump 2 is slightly opened and the water including the foreign matter is discharged, and the delivery valve 9 is closed when the water level is lowered to be near the lowermost operation water level LLWL, the foreign matter is transferred to a drain pit 16 by injection water of the nozzle pipe 12, and the foreign matter is discharged together with the remaining water by a sewage pump 17 of the drain pit 16, and thereby the foreign matter is prevented from being accumulated on a bottom of a tank of the pumping well 1 or the sewage is prevented from being retained in the pumping well 1, and occurrence of the bad smell is prevented. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a pump well installed in a rainwater pumping station of a combined sewer or a drainage station of a river, etc., and a pump that uses a drainage pump while performing a management operation when the pump drainage operation is stopped after the increase of water due to rain or the like The present invention relates to a foreign matter discharge method and a foreign matter discharge device.

  The drainage pump station and the sewage pump station need to be operated in response to a sudden change in the amount of rainwater in the rain, and it is not allowed to be inoperable. Although it is necessary to carry out a management load operation at normal times, water for management operation cannot be secured, so only a very short time operation can be performed. Therefore, there is a case where a return pipe to the pump well is installed and a long-time management operation is performed. In addition, fine sand and other inorganic materials that could not be collected by the sand basin and dust remover, and organic matter such as sediments settle and accumulate in the pump well, and the water in the pump well stays when not in operation, causing organic matter to rot and bad odor. There was a problem that occurred. Therefore, it is also desired to discharge the sediment and suspended matter out of the system by stirring and flowing while preventing sedimentation of foreign matter in the pump well in order to discharge sand and residue and prevent bad odor due to organic matter. For example, as described in Patent Document 1, a device provided with a communication valve between a discharge side of a pump and a suction side water channel is provided as an apparatus for discharging sedimentation sand and the like, and is injected into the suction side water channel. A drainage pump device that floats accumulated sediment and discharges it to the discharge side where the sand basin is located is known. Patent Document 2 relates to a sand basin of a sewage treatment facility, and supplies pressurized water from a water tank to a nozzle disposed at the bottom of the tank to transfer sand and the like to a sand collecting pit and discharges it with a sand pump. Sand devices are also known.

Japanese Patent No. 2995600 (paragraph number 0028, FIG. 1) JP 2002-282609 A (paragraph number 0008, FIG. 1)

  The conventional device that injects discharged water into the suction-side waterway and floats the sediment is a proposal related to the closed pit and the post-sedimentation basin, and since there is a treatment tank downstream, operation and sand removal are easy. Although effective, it was insufficient to float the entire sediment of the pump well. In addition, the sand collecting device that supplies pressurized water from the water tank to the nozzle arranged at the tank bottom and transfers the earth and sand to the sand collecting pit can devise the shape of the bottom surface of the water tank in order to collect the sediment. Since the pump suction tank is made for the pump, it is difficult to devise sand collection, a water tank and a pressure pump are required, and the equipment cost becomes high. This invention prevents foreign matter in the pump well from settling, discharges foreign matter together with residual water, and prevents the generation of bad odor due to organic matter, while maintaining the actual load operation when the pump drainage operation is stopped. A method and a foreign matter discharge apparatus are provided.

  The foreign matter discharge method for a pump well according to the present invention is a pump well in which a drainage pump is installed in the pump well and the pump drainage operation is performed at the time of water increase due to rainfall or the like, and then the maintenance operation of the drainage pump is performed. Management operation is started with the water level maintained at or above the minimum operating water level, the drain pump discharge valve is closed, the drain pump discharge water is injected near the bottom of the pump well, and the drain pump discharge valve is slightly When the water drops to near the minimum operating water level, the discharge valve is closed, the foreign matter is transferred to the drainage pit with the spray water from the drainage pump, and the foreign matter is removed with the sewage pump. It is discharged together, and it is possible to discharge foreign matters such as sand and residue by stirring and flowing while preventing sedimentation of foreign matters in the pump well. And since foreign matter is discharged | emitted out of the system with the residual water of the tank bottom of a pump well, the water of a pump well stays at the time of non-operation, and organic matter is not decayed, and generation | occurrence | production of a bad odor can be prevented.

  The foreign matter discharge method of the pump well according to another invention may discharge the contaminated water by branching from the return pipe that is transferred to the pump well without opening the discharge valve of the drainage pump during the management operation. The amount of foreign matter mixed in the discharge tank can be reduced. Another method for discharging foreign matter from pump wells is to discharge foreign matter mixed water with the sewage pump installed in the drainage pit without opening the discharge valve of the drainage pump during management operation, requiring extra piping. In addition, foreign matter-mixed water and residual water can be discharged out of the system.

  The apparatus for carrying out the foreign matter discharging method of the pump well is configured such that the return pipe connected to the discharge pipe of the drainage pump is connected to the nozzle pipe arranged near the tank bottom of the pump well, and the diameters of the plurality of nozzles of the nozzle pipe are connected. With a partition plate standing near the lower part of the suction casing of the drainage pump, passing through a nozzle with a foreign substance passage diameter along with the discharge water without clogging the foreign matter flowing into the drainage pump. Can be made. Larger nozzles can reduce pressure loss, thus preventing abnormal vibrations and pumping temperature rise due to drain pump deadlines. The partition plate for suction rectification reduces the suction vortex flow, reduces the suction of the submersible vortex of the drainage pump, and can reduce the minimum operating water level as much as possible.

  The nozzle ejection direction provided in the nozzle piping forms a drainage pit with a sewage pump installed at an appropriate location in the pump well, and the sewage pump opens the nozzle at the direct view position toward the sewage pump and directly looks at the sewage pump. The remaining nozzles are opposed to the front surface in the jetting direction of the nozzles using the reflection angle of the partition plate, and sediment can be efficiently discharged together with residual water without sedimentation. Foreign matter and residual water are discharged with a small-diameter pump, so the water at the bottom of the drain pit formed in the pump well can be discharged. Also, the drainage pipe may be branched from the return pipe, and a water control valve and an on-off valve may be provided on the rear side of the branch point to discharge the foreign matter mixed water to another system. Since it can be transferred to a sewer or a concentration tank, the amount of foreign matter mixed in the discharge tank is reduced, and equipment can be reduced.

  By carrying out the maintenance and actual load operation of inorganic substances such as sand and the like flowing into the pump well and the organic matter such as residue when the pump drainage operation is stopped, the foreign matter settled and accumulated in the pump well can be stirred and flowed. The suspended foreign matter is discharged together with the stored water, and the sediment and residual water are discharged by a small-diameter pump installed in the drain pit, so that the water at the bottom of the pump well can be discharged. And when the drainage pump is stopped, there is no residual water and deposits staying in the pump well, and it is possible to prevent the generation of bad odor due to the decay of organic matter. Further, the nozzle having a foreign substance passage diameter is not clogged, and the nozzle having a large diameter has little pressure loss and can prevent the drainage pump from being closed.

  FIG. 1 is a longitudinal sectional view of a pumping station, and a pumping well disposed in a rainwater pumping station of a combined sewer, a river drainage station, or the like. 1 is provided with a drainage pump 2. Pump well 1 in which inorganic substances such as sand are precipitated from turbid water flowing into the sand basin 3 by increasing water due to rainfall, etc., and organic substances such as residue are separated by a dust remover (not shown) Allow turbid water to flow down. In this embodiment, the drainage pump 2 is constituted by a vertical shaft mixed flow pump, but the drainage pump may be a vertical shaft axial flow pump or a horizontal shaft mixed flow pump. The drainage pump 2 is erected in the vicinity of the side wall on the discharge tank 4 side, the suction port 5a of the suction casing 5 on the suction side is opened near the tank bottom of the pump well 1, and the backflow prevention valve on the discharge side of the discharge pipe 6 is provided. 7 protrudes from the discharge tank 4. The diesel engine 8 linked to the drain pump 2 is driven to pump the stored water in the pump well 1 into the discharge tank 4.

  FIG. 2 is a side view of the drainage pump 2 installed in the pump well 1. A discharge valve 9 is provided in the discharge pipe 6 of the drainage pump 2, and the pump well 1 is suspended in the discharge pipe 6 on the suction side of the discharge valve 9. The return pipe 10 is connected, and a water control valve 11 is interposed in the return pipe 10. A nozzle pipe 12 installed horizontally is connected to the lower end of the return pipe 10 in the vicinity of the bottom of the pump well 1, and a plurality of nozzles 13 are fixed to the nozzle pipe 12. If the discharge valve 9 disposed in the discharge pipe 7 is closed, the water control valve 11 of the return pipe 10 is opened, and the drainage pump 2 is operated, the pressurized discharge water is caused to flow into the return pipe 10, Pressurized water is jetted from the nozzle 13 of the nozzle pipe 12. Sand and other inorganic substances such as sand that have flowed into the pump well 1 are stirred and flowed with pressurized water from the jet nozzle 13 to prevent sedimentation. Suspend organic matter.

  The diameter of the nozzle 13 to be used is (length) 70 to 150 mm × (width) 20 to 40 mm, and the diameter can be appropriately selected according to the properties of the water flowing into the pump well. It is a diameter through which foreign matter can pass. Even if inorganic substances such as fine sand that could not be collected by the sand basin and the dust remover and organic matter such as residue flow into the drainage pump 2, the nozzle 13 of the nozzle pipe 12 becomes clogged if the diameter of the nozzle 13 is set as the foreign substance passage diameter. You can pass without Since the large-diameter nozzle 13 can reduce pressure loss, it can prevent abnormal vibration and pumping water temperature rise due to the deadline of the drainage pump 2.

  FIG. 3 is a conceptual diagram of a drainage pump and nozzle piping installed in a pump well, and a plurality of drainage pumps 2 are installed, and a partition wall that prevents disturbance of water flow between the drainage pumps 2 and 2 14 is erected. The partition wall 14 prevents the drainage pumps 2... From interfering with each other's suction flow. A partition plate 15 for suction rectification is provided at the bottom of the tank near the suction port 5 a of the suction casing 5 of the drain pump 2, and the partition plate 15 reduces the suction vortex of the drain pump 2. The suction of the underwater vortex of the drainage pump 2 is reduced, and the minimum operating water level LLWL can be lowered as much as possible. A drainage pit 16 is formed at one corner of the bottom of the pump well 1 to discharge inorganic substances such as sand and organic matter such as residue with residual water, and a small-diameter sewage pump 17 is installed in the drainage pit 16. .

  As shown in FIG. 3, a pair of nozzle pipes 12, 12 extending toward the sand settling basin 3 are close to the partition wall 14 on both sides of the partition plates 15 below the plurality of drainage pumps 2. They are facing each other. The pair of nozzle pipes 12 are connected to a return pipe 10 disposed in one drain pump 2. In the ejection direction of the nozzle 13 of the nozzle pipe 12, the nozzle 13 at a position directly viewed from the sewage pump 17 is opened toward the sewage pump 17. The remaining nozzles 13 where the partition wall 14 and the partition plate 15 shield the direct view of the sewage pump 17 have a reflection angle on the front surface in the injection direction of the nozzle 13 that directly views the sewage pump 17 using the reflection angle of the partition plate 15. They are facing each other.

  The inorganic material such as sand and the organic matter such as sediment deposited in the pump well 1 is made to flow with the jet water from the nozzle 13 of the nozzle pipe 12 or the sediment is transferred and the floating foreign matter is discharged into the drain pit 16 by the water flow of the jet water. Accumulated and discharged by the sewage pump 17. Since sediment and residual water are discharged by the small-diameter sewage pump 17 installed in the drainage pit 16, the water at the bottom of the pump well 1 can be discharged. Since the foreign matter is discharged out of the system together with the residual water, the water in the pump well 1 does not stay and the organic matter does not decay during non-operation, and the generation of malodor can be prevented. In addition, although all the nozzles 13 of the nozzle pipes 12... Installed may be sprayed simultaneously, one or two nozzles on the side far from the drain pit 16 in consideration of the amount of water and the jet energy. It is desirable to inject pressurized water from the pipe 12 and to switch to the nozzle pipe 12 on the closer side and inject it little by little.

  The discharge method using the foreign matter discharge device of the pump well will be described in detail. In the drainage pump station of the combined sewer and the sewage pump station of the river, the inflow amount of the pump well 1 increases due to the sudden increase of rainwater during the rain. . Part of the inorganic substance such as sand and organic matter such as sediment contained in the muddy water flows into the drainage pump 2 through the sand basin and the dust remover. As shown in FIG. 1, the pump drainage operation of the drainage pump 2 operates a plurality of drainage pumps 2... According to the inflow amount from the pump operation water level HWL to the minimum operation water level LLWL. When the amount of inflow into the pump well 1 decreases and the pump drainage operation is stopped, the discharge valve 9 of the drainage pump 2 is closed while the water level is maintained at the minimum operation water level LLWL or higher. Next, the operation is switched to the actual maintenance load operation, the control valve 11 of the return pipe 10 connected to the drain pump 2... Is opened, and the discharge water of the drain pump 2 is pumped to the nozzle pipe 12 of the pump well 1. . Discharge water is jetted near the tank bottom of the pump well 1 to cause the precipitate and suspended matter to stir and flow, and after a predetermined time, the discharge valve 9 of the drain pump 2 is slightly opened to discharge the foreign matter mixed water.

  As shown in FIG. 4, when the water level decreases from the pump operation water level HWL, the backflow water of the drainage pump 2 is generated by the small flow rate operation, and the foreign matter floats and flows. When the level drops to near the minimum operating water level LLWL, the discharge valve 9 of the drainage pump 2 is closed, and the discharge water of the drainage pump 2 is injected from all the nozzle pipes 12. Is switched to the nozzle pipe 12 of the drainage pump 2, and the sediment and the suspended matter are transferred to the drainage pit 16 with the jet water, and the drainage pump 2 is stopped. Next, the sediment in the drain pit 16 is discharged together with the residual water by the small-diameter sewage pump 17 in the drain pit 16. Since the water in the drain pit 16 can be discharged, foreign matter does not accumulate on the bottom of the pump well 1 or sewage stays in the pump well 1 so that no bad odor is generated.

  FIG. 5 shows another embodiment of the foreign matter discharging apparatus, in which a drainage pipe 19 having an opening / closing valve 18 is branched on the upstream side of the water control valve 11 provided in the return pipe 10. The discharge valve 9 was closed, and the residual water in the pump well 1 was stirred and flowed with the discharge water from the drain pump 2, and then the water control valve 11 disposed in the return pipe 10 was opened. As it is, the on-off valve 18 of the branched mud pipe 19 is opened and discharged to a sewer or a concentration tank or the like of another system, or discharged to the discharge tank 4 to reduce the water level to the vicinity of the lowest operating water level LLWL. It is good. FIG. 6 shows another embodiment of the foreign matter discharging method, in which the residual water in the pump well 1 is agitated and flowed while the actual load operation of the drainage pumps 2. 17 may be operated and discharged from the drain pipe 20 to a sewer or a concentration tank, and the water level may be lowered to the vicinity of the minimum operating water level LLWL.

  The foreign matter discharge method and foreign matter discharge device of the pump well according to the present invention are configured as described above, and when the pump drainage operation is stopped, the precipitate and the suspended matter are agitated and flowed while performing the operation and maintenance actual load operation. Since the water up to the pit 16 can be discharged, no foreign matter accumulates on the bottom of the pump well 1 or sewage stays in the pump well 1 so that no bad odor is generated. Therefore, it is suitable as a foreign matter discharging method and a foreign matter discharging device for a pump well disposed in a rainwater pumping station of a combined sewer or a drainage station of a river.

It is a longitudinal cross-sectional view of the pump station which arrange | positioned the foreign material discharge apparatus in the pump well which concerns on this invention. Similarly, it is a side view of the drainage pump installed in the pump well. Similarly, it is the conceptual diagram of the drainage pump and nozzle piping installed in the pump well. Similarly, it is a conceptual diagram which shows the state which the backflow water of a drainage pump generate | occur | produces by a small flow rate driving | operation. Similarly, it is a side view of the other Example of a foreign material discharge apparatus. Similarly, it is a side view of another embodiment of the foreign matter discharging apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pump well 2 Drain pump 5 Suction casing 6 Discharge pipe 9 Discharge valve 10 Return pipe 12 Nozzle pipe 11 Water control valve 13 Nozzle 15 Partition plate 16 Drain pit 17 Sewage pump 18 On-off valve 19 Drain pipe LLWL Minimum operation water level

Claims (6)

After installing the drainage pump (2) in the pump well (1) and performing pump drainage operation at the time of water increase due to rain, etc., in the pump well (1) performing maintenance operation of the drainage pump (2), Management operation is started with the water level of 1) maintained at the minimum operating water level (LLWL) or more, the discharge valve (9) of the drain pump (2) is closed, and the water is drained near the bottom of the pump well (1). When the discharge water of the pump (2) is injected, the discharge valve (9) of the drainage pump (2) is slightly opened to discharge the flowing foreign material mixed water, and the discharge valve is lowered to the vicinity of the minimum operating water level (LLWL) (9) is closed, the foreign matter is transferred to the drainage pit (16) with the jet water from the drainage pump (2), and the foreign matter is discharged together with residual water by the sewage pump (17). Foreign matter discharge method. At the time of the management operation, the discharge valve (9) of the drain pump (2) is not opened, and the branch water is branched from the return pipe (10) to be transferred to the pump well (1) to discharge the foreign water. The method for discharging foreign matter from a pump well according to claim 1. 2. The foreign matter mixed water is discharged by the sewage pump (17) installed in the drain pit (16) without opening the discharge valve (9) of the drain pump (2) during the management operation. The foreign matter discharge method of the pump well as described in 2. In the pump well (1) which installs the drainage pump (2) in the pump well (1) and performs the pump drainage operation at the time of water increase due to rain, etc., and then performs the maintenance operation of the drainage pump (2).
A return pipe (10) connected to the discharge pipe (6) of the drainage pump (2) is connected to a nozzle pipe (12) disposed near the bottom of the pump well (1), and a plurality of nozzle pipes (12) are connected. The nozzle well (13...) Has a foreign substance passage diameter, and a partition plate (15) is erected in the vicinity of the lower portion of the suction casing (5) of the drainage pump (2). Foreign matter discharge device. A drainage pit (16) in which a sewage pump (17) is installed at an appropriate position of the pump well (1) is formed, and the ejection direction of the nozzle (13 ...) of the nozzle pipe (12) is directed to the sewage pump (17). The nozzle (13...) At the direct viewing position is opened toward the sewage pump (17), and the partition plate (15 The foreign matter discharging apparatus for a pump well according to claim 4, wherein the remaining nozzles (13. The mud pipe (19) is branched from the return pipe (10), and a water control valve (11) and an on-off valve (18) are arranged on the rear side of the branch point, respectively, to discharge foreign matter mixed water to another system. The foreign matter discharging apparatus for a pump well according to claim 5.

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