JP4967456B2 - Screen pressure feeding method and apparatus - Google Patents

Description

  The present invention is a method and apparatus for pressure-feeding residue, in particular, when the residue (sewage suspended matter such as wood, paper, vinyl, cloth, dead leaves) generated in the process of sewage treatment is pumped by a piston pump. The present invention relates to a residue pressure feeding method and apparatus capable of reliably and inexpensively preventing the residue transfer tube from being blocked due to compaction even if the properties of the residue change due to weather or the like.

  Conventionally, as a sewage treatment facility equipped with a confluence sand basin, there is one disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 11-342305). Hereinafter, this sewage treatment facility will be described with reference to the drawings.

  FIG. 5 is a partial schematic front view showing the sewage treatment facility, FIG. 6 is a schematic sectional view showing the piston pump of the residue pumping facility, FIG. 7 is a schematic plan view showing the sand basin of the sewage treatment facility, and FIG. It is a schematic front view which shows the dust remover installed in the sand basin.

  5 to 8, reference numeral 14 denotes a sand basin for slowly flowing sewage and sinking and removing sand in the sewage in the course of this flow. The sand basins 14 are installed in parallel in the basement in a plurality of rows (in this example, 5 rows). 14A is a sewage inflow port, and 14B is a sewage drain. Reference numeral 15 denotes a dust remover installed on the downstream side of each sand settling basin 14 for scraping the residue (S) in the sewage out of the sand settling basin 14. As shown in FIG. 8, the dust remover 15 is installed on the upstream side of the screen 16 provided across the width direction of the sand basin 14, and removes the residue (S) in the sewage that circulates endlessly by the motor 17. A scraper 18 for scraping out the sand basin 14 is provided.

  Reference numeral 19 denotes a stag transport facility for collecting the scum (S) scraped by the dust remover 15 and transporting the scum (S) to a scum storage hopper 20 installed on the ground. The residue transporting equipment 19 includes first transport means 21 for collecting the residue (S) scraped out by each dust remover 15, and storing the residue collected by the first transport means 21 on the ground. It consists of second conveying means 22 for conveying to the hopper 20.

  The first transport means 21 is composed of a collective transport means 21A and an intermediate transport means 21B each composed of a chain conveyor or the like, and the second transport means 22 is constituted by an adjustment tank 23 and a screen pressure feeding device 24. .

  The adjustment tank 23 is for temporarily storing the residue transported by the first transport means 21. The residue (S) stored in the adjustment tank 23 is sent to the residue pressure feeding device 24 by the conveyor 25.

  The residue pumping device 24 includes a piston pump 7 and a residue transport pipe 8 connected to the piston pump 7 via a gate valve 12 described later. As shown in FIG. 6, the piston pump 7 is provided on the discharge cylinder 9, a discharge piston 9 that reciprocates by hydraulic pressure, a discharge cylinder 10 in which the loaded residue (S) is compressed by the discharge piston 9, and the discharge cylinder 10. It comprises a hopper 11 and a gate valve 12 for opening and closing the discharge cylinder 10.

  The piston pump 7 intermittently feeds residue (S) from the hopper 11 into the discharge cylinder 10 through the residue transport pipe 8 to the residue storage hopper 20 by reciprocating movement of the discharge piston 9 and opening and closing of the gate valve 12. Pump.

  According to the sewage treatment facility configured as described above, sewage is treated as follows.

  Sewage flows into each sand basin 14 from the inflow port 14 </ b> A and flows slowly through the sand basins 14. In the course of this flow, the sand in the sewage settles and accumulates in the pit 14C at the bottom of the sand basin 14. The sand accumulated in the pit 14C is scraped out of the sand basin 14 periodically by a scraper (not shown). When the sewage flows to the downstream side of the sand basin 14, the residue (S) in the sewage is scraped out by the scraper 18 of the dust remover 15. In this way, the sewage from which the sand and the residue (S) are removed is discharged from the drain port 14B into, for example, a river or sent to the next processing step.

  On the other hand, the residue (S) scraped out by each dust remover 15 is put into the adjustment tank 23 of the second transport means 22 by the first transport means 21. The residue (S) charged into the adjustment tank 23 is charged into the hopper 11 of the piston pump 7 by the conveyor 25. The residue (S) charged into the hopper 11 is sent into the discharge cylinder 10 with the gate valve 12 closed, and then compressed by the advance of the discharge piston 9. When the residue (S) is compressed in this way, the gate valve 12 is opened, and then the discharge piston 9 moves forward. As a result, the residue (S) in the discharge cylinder 10 is intermittently conveyed to the residue storage hopper 20 through the residue conveying pipe 8.

JP 11-342305 A

  By adopting the above-described residue pressure feeding device 24 using the piston pump 7 in such a sewage treatment facility, the following effects can be obtained.

(1) Since the residue transport pipe 8 can be completely sealed, there is no fear of generation of bad odor or water leakage between the piston pump 7 and the residue storage hopper 20.
(2) Since the residue transport pipe 8 can be bent freely, the residue (S) transport route from the piston pump 7 to the residue storage hopper 20 can be set freely.

  However, the conventional residue pressure feeding device 24 has the following problems.

  The properties of the residue change depending on the weather. In other words, paper and cloth occupy the majority of the residue component in fine weather, and vegetation accounts for the majority of the residue component in rainy weather. Therefore, the bulk density of the screen residue during rainy weather is lower than the bulk density of the screen residue during fine weather. When such bulk density is low and the residue is pushed into the residue transport pipe 8 by the piston pump 7, it is easy to consolidate. Once the residue is compacted in the residue transport pipe 8, the frictional resistance with the inner wall surface of the residue transport pipe 8 increases, and in some cases, pressure feeding cannot be performed.

  As a method of solving this problem, there is a method of adding a lubricant and injecting it into the residue transport pipe 8, but it is difficult to inject a lubricant into the compacted portion at a pinpoint, even if it can be injected at a pinpoint. When water-absorbing gel or fats and oils are used as a lubricant, running cost is increased.

  Accordingly, an object of the present invention is to reliably and inexpensively prevent clogging of a clog transport pipe due to compaction even when the slag generated in the sewage treatment process is pumped by a piston pump even if the bulk density of the slag is low. Another object is to provide a residue pressure feeding method and apparatus.

  The inventors of the present invention have made extensive studies to solve the above-described problems. As a result, if water is supplied to the residue in the residue transport pipe every cycle of the piston piston discharge piston, the residue transport tube can be reliably prevented from being blocked by compaction even if the bulk density of the residue is low. Moreover, the knowledge that it is cheap because it uses water was obtained.

  The present invention has been made on the basis of the above findings, and is characterized by the following.

The invention according to claim 1 uses a piston pump having a discharge piston, a discharge cylinder, and a gate valve provided on the discharge side of the discharge cylinder, and fills residue in the discharge cylinder with the gate valve closed. A filling step, a compression step of compressing the residue in the discharge cylinder by the discharge piston, and opening the gate valve to connect the compression residue in the discharge cylinder to the discharge cylinder by the discharge piston. In the residue pressure feeding method in which the residue is conveyed through the residue conveyance tube by repeatedly performing the extrusion step of extruding into the residue conveyance tube, in the vicinity of the connecting portion between the gate valve and the residue conveyance tube, was extruded into渣搬feed tube, one stroke compressed residue of the dispensing piston, only between the filling process of the compressing step, the Condensation to keep the filling rate of the residue to constant, after the water supply continues to compaction does not occur, through the compressed residue of the one stroke in which the water supply is performed, the newly extruded by the extrusion process The compressed residue for one stroke that is not supplied with water is previously pushed out to the residue transport pipe, and the compressed residue that has been supplied with water is pushed forward to advance the compressed residue. It is characterized in that it is moved without being compacted, thus preventing the residue transport tube from being blocked.

  According to a second aspect of the present invention, in the first aspect of the present invention, when the pressure in the residue transport pipe is detected and the pressure value exceeds a reference value, the piston pump is stopped and the residue transport is performed. It is characterized by continuously supplying water into the pipe.

The invention according to claim 3 is a piston pump having a discharge piston, a discharge cylinder, and a gate valve provided on the discharge side of the discharge cylinder, and a residue transport pipe connected to the discharge cylinder via the gate valve; The piston pump includes a filling step of filling residue into the discharge cylinder with the gate valve closed, a compression step of compressing residue within the discharge cylinder by the discharge piston, and the gate Residue pressure feeding device that conveys the residue through the residue conveying pipe by repeatedly performing the extrusion process of opening the valve and extruding the compressed residue in the discharge cylinder into the residue conveying tube by the discharge piston in, at the junction vicinity of the aforementioned residue conveying pipe and the gate valve was extruded to the above渣搬feed pipe, the discharge piston The compressed residue of stroke, only between the filling process of the compressing step, said maintaining a filling rate of the compressed residue constant, by performing the water supply continues to so compaction does not occur, the aforementioned residue conveyance tube A water supply means for preventing the blockage of the water is provided, and the compressed residue for one stroke not supplied with water is newly pushed out in the extrusion process through the compressed residue for one stroke when the water is supplied. However, by pressing the compressed slag that has been previously fed into the scum transport pipe and having been supplied with water, the compressed slag is moved without being compressed, and thus the slag transport pipe is moved . It is characterized by preventing occlusion.

  According to a fourth aspect of the present invention, in the third aspect of the present invention, the pressure switch for detecting the pressure in the residue transport pipe, and a stop command to the piston pump are issued when the pressure value exceeds a reference value. And a control means for issuing a command for continuously supplying water to the residue transport pipe to the water supply means.

  According to this invention, when the residue generated in the sewage treatment process is pumped by the piston pump, even if the bulk density of the residue is low, the blockage of the residue transport pipe due to compaction is reliably and inexpensively prevented. Can do.

  Hereinafter, an embodiment of the residue pressure feeding device of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing a residue pumping device of the present invention, FIGS. 2A to 2H are diagrams of a residue pumping process of the first cycle by the residue pumping device of the present invention, FIG. ) To (P) are diagrams of the second-stage screen pressure feeding process by the screen pressure-feeding device of the present invention, FIG. 4 is a conceptual diagram showing the state of pressure-feeding of the screen residue by the piston pump, and FIG. The conceptual diagram when there is no water supply, the same figure (B) is a conceptual diagram when there is water supply.

  As shown in FIG. 1, the residue pumping device according to the present invention comprises a piston pump 7 and a residue transport pipe 8 as in the conventional residue pumping device described above. The piston pump 7 includes a discharge piston 9 that reciprocates by a hydraulic unit 13, a discharge cylinder 10 in which charged residue (S) is compressed by the discharge piston 9, a hopper 11 provided on the discharge cylinder 10, It consists of a gate valve 12 driven by a hydraulic unit 13 for opening and closing the discharge cylinder 10. The residue transport pipe 8 is connected to the discharge cylinder 10 through a gate valve 12.

  The piston pump 7 is a filling process for filling the residue in the discharge cylinder 10 with the gate valve 12 closed, a compression process for compressing the residue in the discharge cylinder 10 by the discharge piston 9, and the gate valve 12 is opened. Thus, the discharge piston 9 compresses the residue in the discharge cylinder 10 and extrudes it into the residue transport pipe 8 repeatedly, and the residue is transported through the residue transport pipe 8.

  The residue pressure feeding device of the present invention is characterized in that a compressed residue (a residue conveyance pipe near the outlet of the piston pump 7) is pushed out to the residue conveyance pipe 8 in the vicinity of the connecting portion between the gate valve 12 and the residue conveyance pipe 8. 8 is provided with a water supply means 1 for supplying water to the compressed residue in 8) from the filling step to the compression step.

  The water supply means 1 includes a water supply pipe 2 connected to the residue transport pipe 8 in the immediate vicinity of the outlet of the piston pump 7, a water supply valve 3 provided in the middle of the water supply pipe 2, and water in the water supply tank 4 through the water supply valve 3. And a pump 5 for supplying to the water supply pipe 2. The pump 5 is preferably a constant flow pump such as a plunger pump that hardly changes the amount of water supplied even if the pressure changes.

  Next, the residue transporting process by the residue pressure feeding apparatus of the present invention will be described with reference to FIGS.

  First, as shown in FIG. 2A, the residue (S) in the hopper 11 is filled in the discharge cylinder 10, and the operation in the first cycle is started. At this time, the gate valve 12 is closed. Next, as shown in FIG. 5B, the discharge piston 9 advances to the intermediate position and stops. In this manner, the residue (S) compression process is completed.

  Next, as shown in FIG. 6C, after the gate valve 12 is opened, as shown in FIG. 4D, the discharge piston 9 moves forward, and the residue (S) is removed in the residue transport pipe 8. To be pumped. When the pumping of the residue (S) for one stroke is completed in this way, the gate valve 12 is closed as shown in FIG. In this way, the residue extrusion process is completed.

  Thereafter, as shown in FIG. 5F, water supply from the water supply pipe 2 is started to the compressed residue (S) pushed out to the residue transport pipe 8. During this period, as shown in FIG. Water supply continues during this time. And as shown to the figure (H), the discharge piston 9 reverse | retreats to the operation start position of the following 2nd cycle, and stops. During this time, new residue is filled in the discharge cylinder 10. Water supply continues during this time. In this way, the residue (S) filling process is completed.

  Next, as shown in FIGS. 3I to 3P, the compression process, the extrusion process, and the filling process in the second cycle are performed. That is, (I) and (J) in the figure are compression steps, (K), (L) and (M) are extrusion steps, and (F), (G) and (H) are filling steps. It is.

  By repeatedly performing the above steps, the residue (S) is conveyed through the residue conveying tube 8. Then, by supplying water to the compressed residue (S) pushed out to the residue transport pipe 8 during the filling process to the compression process, the bulk density is low as in the case of a residue in rainy weather. However, the residue (S) can be reliably conveyed to the residue storage hopper 20 or the like of the sewage treatment facility without causing the residue conveyance tube 8 to be blocked due to compaction.

  FIG. 4 shows a state in which the residue is pumped by the piston pump. As shown in FIG. 4 (A), when there is no water supply, the residue is gradually consolidated as the pressure is fed. As shown in B), when there is water supply, the filling rate of one residue to the residue transport pipe 8 is kept constant, so that compaction does not occur.

  It should be noted that water supply to the compressed residue (S) is always performed regardless of the properties of the residue, or when the bulk density of the residue is known in advance, the bulk density is low. Water may be supplied only in this case.

  Further, as shown in FIG. 1, when a pressure switch 6 is provided in the feed water pipe 2 and the pressure feed pressure value of the residue in the residue transport pipe 8 exceeds a reference value, a control means (not shown) In addition to issuing a stop command to the piston pump 7, a command may be issued to the water supply means 1 to continuously feed water into the residue transport pipe 8 and discharge the compacted residue.

  As described above, according to the residue pumping device of the present invention, when the residue generated in the sewage treatment process is pumped by the piston pump 7, even if the bulk density of the residue is low, the gate valve 12 is used as the residue. By supplying water to the compressed residue pushed out into the residue transport tube 8 in the vicinity of the connecting portion with the transport tube 8 from the filling process to the compression process, the residue transport tube 8 is surely blocked by the compaction. Can be prevented. Moreover, it is inexpensive because it uses water without using expensive lubricants.

It is a schematic block diagram which shows the residue pressure feeding apparatus of this invention. It is a 1st cycle residue pressure feed process figure by the residue pressure feed apparatus of this invention. FIG. 4 is a second cycle residue pressure feeding process diagram by the residue pressure feeding device of the present invention. It is a conceptual diagram which shows the pumping state of the residue by a piston pump, The figure (A) is a conceptual diagram when there is no water supply, and the same figure (B) is a conceptual diagram when there is water supply. It is a partial schematic front view which shows a sewage treatment facility. It is a schematic sectional drawing which shows the piston pump of a residue pressure feeding equipment. It is a schematic plan view which shows the sand basin of a sewage treatment facility. It is a schematic front view which shows the dust remover installed in the sand basin.

Explanation of symbols

1: Water supply means 2: Water supply pipe 3: Water supply valve 4: Water supply tank 5: Pump 6: Pressure switch 7: Piston pump 8: Slag transport pipe 9: Discharge piston 10: Discharge cylinder 11: Hopper 12: Gate valve 13: Hydraulic unit 14: Sand basin 14A: Inlet 14B: Drain port 14C: Pit 15: Dust remover 16: Screen 17: Motor 18: Scraper 19: Sediment transport equipment 20: Sediment storage hopper 21: First transport means 21A: Collective conveying means 21B: intermediate conveying means 22: second conveying means 23: adjustment tank 24: residue pressure feeding device 25: conveyor

Claims (4)

Using a piston pump having a discharge piston, a discharge cylinder and a gate valve provided on the discharge side of the discharge cylinder, and filling the residue into the discharge cylinder with the gate valve closed; A compression step of compressing the residue in the discharge cylinder, and opening the gate valve to push the compressed residue in the discharge cylinder into the residue transport pipe connected to the discharge cylinder by the discharge piston. In the residue pressure feeding method in which the residue is conveyed through the residue conveyance tube by repeatedly performing the extrusion step.
In the vicinity of the connecting portion between the gate valve and the residue transporting pipe, the compressed residue for one stroke of the discharge piston pushed into the residue transporting pipe, only during the compression process from the filling process, After the compression, the filling rate of the residue is kept constant, and water is continuously supplied so that the compaction does not occur. The compressed residue for one stroke that has been pushed out and is not supplied with water is pushed forward by the compressed residue that has been previously pushed into the residue transport pipe and has been supplied with water. The method for transporting a residue is characterized in that the residue is moved without being compacted, thus preventing the residue transport tube from being blocked.   The pressure in the residue transport pipe is detected, and when the pressure value exceeds a reference value, the piston pump is stopped and water is continuously supplied into the residue transport tube. Debris pressure feeding method as described. A piston pump having a discharge piston, a discharge cylinder, and a gate valve provided on the discharge side of the discharge cylinder; and a residue transport pipe connected to the discharge cylinder via the gate valve, A filling step of filling residue into the discharge cylinder with the gate valve closed; a compression step of compressing residue within the discharge cylinder by the discharge piston; and opening the gate valve to open the discharge piston. In the residue pressure feeding device that conveys the residue through the residue conveyance tube by repeatedly performing the extrusion process of extruding the compressed residue in the discharge cylinder into the residue conveyance tube by:
In the vicinity of the connecting portion between the gate valve and the residue transporting pipe, the compressed residue for one stroke of the discharge piston pushed into the residue transporting pipe, only during the compression process from the filling process, The one-stroke in which the water supply means is provided to keep the filling rate of the compressed residue constant and to continuously supply water so that compaction does not occur and to prevent the residue transfer tube from being blocked. The compressed residue for one stroke, which is newly pushed out in the extrusion process and is not supplied with water, is first pushed out to the residue transport pipe, and water is supplied. A squeeze pressure feeding device characterized in that the squeeze is pushed and moved forward to move the compressed scum without compaction, thus preventing clogging of the scum transport pipe.   A pressure switch for detecting the pressure in the residue transport pipe, and a stop command to the piston pump when the pressure value exceeds a reference value, and a command for continuously supplying water into the residue transport pipe The screen pressure feeding device according to claim 3, further comprising control means for emitting the means.

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