JP4758743B2 - Equipment for separating and removing solids in liquid - Google Patents

Description

  The present invention belongs to the technical field of a device for separating and removing solid content in drainage. More specifically, the present invention belongs to the technical field of a processing apparatus that separates and removes solids contained in the drainage discharged from a dehydrator or a concentrator of a sludge processing apparatus.

  Sludge generated from sewage treatment, industrial wastewater treatment, etc. has been subjected to sludge concentration treatment and dewatering treatment in order to reduce costs and improve treatment efficiency in subsequent treatment and disposal. In conventional concentrators and dehydrators used for concentration and dehydration, solids containing 5% to 10% of the amount of solids to be treated are contained on the separation liquid side. It was. However, in recent years, it has been required to increase the solids recovery rate to about 98% to 95%, improve the quality of the return water, and reduce the load on the water treatment system. For this reason, an apparatus in which an apparatus for further performing a solid-liquid separation process from the separated liquid is incorporated into a concentrator or a dehydrator is being developed.

Such a device is generally developed as an accessory device of the main device. Such a device is not found in the patent documents that have been publicly disclosed. Therefore, here, a conventional device (hereinafter referred to as the conventional device 1) described in the technical manual as an accessory device of the sludge treatment device described in Non-Patent Document 1 will be described. However, since the technical manual does not provide detailed descriptions of the functions, some explanations will be supplemented and briefly described. FIG. 7 shows the relevant system of the filtrate separator, and FIGS. 8 and 9 show a front view and a plan view of the apparatus. FIG. 9B is a cross-sectional view taken along arrow X in FIG.
Sludge treatment equipment, press-fit screw press dehydrator, technical manual, 2001-March issue, Sewerage New Technology Promotion Organization

  In FIG. 7, 50 is a press-fitting type screw press dehydrator, and 51 is an aggregating device. 52 is a washing water tank and 53 is a pump. The dehydrated cake dehydrated by the dehydrator 50 is mounted on the belt conveyor 54 by the chute 50a and discharged to the dehydrated cake storage hopper 55. 56 is a filtrate separator, and the filtrate is supplied to the filtrate separator 56 from the hopper 50b. Solids are removed from the filtrate supplied to the filtrate separator 56, the solid sludge is returned to the sludge storage tank, and the clarified water is supplied to the water treatment facility.

  In FIG. 8, FIG. 9 (A), (B), 60 is a filtrate separation tank, 61 is a separation sludge tank. 62 is an inflow pipe 62 for supplying filtrate, and 63 is a cleaning pipe 63 for supplying cleaning water. Reference numeral 64 denotes a filtrate separation tank scraping plate, which scrapes solids that have settled to the bottom of the filtrate separation tank 60. 65 spills the solid matter floating with the scraping blade to the separated sludge tank 61 together with the flowing water overflowing. A hopper-like chute 68 is provided at the upper part of the filtrate separation tank 60 for supplying the floating solid matter scraped by the scraping blade 65 to the separation sludge tank 61.

A small chamber 70 is formed by a partition plate 69 in a part of the separation sludge tank 61 (upper part in FIG. 9), and a communication path is provided between the filtrate separation tank 60 and the small chamber 70 as shown in FIG. 9B. 71 is provided at the intermediate liquid level from the liquid surface. A clear water pipe 73 is provided in the center of the small chamber 70. The separation sludge tank 61 is further provided with a stirring device 75 and a liquid level gauge 76. In addition, a communication pipe 78 is provided for communicating the bottom of the filtrate separation tank 60 and the bottom of the separation sludge tank 61 via an on-off valve (separated sludge extraction valve) 77, and an on-off valve (separated mixed sludge extraction valve) 79 is provided. A conduit 80 is provided between the bottom of the separated sludge tank 61 and the sludge storage tank 8 (FIG. 7).

  As described above, the conventional apparatus 1 always operates the drive unit 67 while the dehydrator 50 is in operation, and the lower solids of the filtrate separation tank 60 are obtained by the lower blade 64 of the scraping machine. Then, the separated sludge extraction valve 77 is opened and moved to the separated sludge tank 61. Further, the solid matter that has floated and separated is scraped by the blade 65 of the scraper, and is discharged from the chute 68 protruding to the upper part of the separated sludge tank 61 to the separated sludge tank 61. Therefore, a power machine for driving the scraping blade 64 and the scraping blade 65 is required. The blade 64, the blade 65, and the drive mechanism complicate the device, increase the size, and increase the weight. Therefore, there arises a problem that the running cost becomes expensive in addition to the device itself. Furthermore, since there are many worn parts, there is a problem that failure is likely to occur and reliability is lacking.

  As described above, the present invention improves the reliability by reducing the number of moving parts as much as possible, and simplifies and downsizes the apparatus by separating the solid content naturally, thereby reducing the cost and reliability of the apparatus. It is an issue to provide.

In order to solve the above problems, the present invention employs the following means. That is,
The invention according to claim 1 is a separation / removal device that separates and removes solids contained in the drainage discharged from a dehydrator, a concentrator, etc. of the sludge treatment apparatus, and the floating solids contained in the drainage. , A separation tank that naturally separates the settled solid content from the liquid content, a drainage supply pipe having an outlet for the drainage in the liquid of the separation tank, a guide groove for collecting the floating solid content, and a solid content storage A storage tank, a second on-off valve provided in a communication path between the guide groove and the storage tank, a liquid level gauge for measuring a liquid level of the storage tank, and an intermediate liquid level of the separation tank. A clarified water separation tank having a communicating hole, a clarified water pipe having a water intake in the clarified water separation tank, a first on-off valve provided in a communication path between the bottom of the separation tank and the bottom of the storage tank, A third on-off valve provided in a communication path communicating the bottom of the storage tank and an external device disposed at an appropriate external position; It is characterized by comprising a control device for controlling the valves.

The invention according to claim 2 is the invention according to claim 1, wherein the liquid level gauge detects a high level, a medium level, and a low level of the liquid level in the storage tank,
The controller is
When the separation and removal device is in operation and the liquid level of the storage tank is at a low level or an intermediate level, the second on-off valve is opened and closed at regular intervals to release the floating solids to the storage tank. The first on-off valve is opened for a predetermined time after the second on-off valve is closed, and the solid content settled on the bottom of the separation tank is caused to flow into the storage tank due to the difference in water level head,
When the liquid level of the storage tank is equal to or higher than the medium level, the stirrer of the storage tank is rotated to mix the floating solids and the precipitated solids,
A control is performed such that when the liquid level of the storage tank reaches a high level, a third on-off valve is opened to deliver the mixed solid content to an external device .

A third aspect of the invention is characterized in that, in the first or second aspect of the invention, a watering device is provided above the liquid level of the separation tank.

  In the present invention, since the rotating members such as the scraping plate and the scraping blade and the driving device are eliminated, it is difficult to cause a failure and the durability is improved. Further, since the solid content is floated or settled by gravity, it is possible to achieve an effect that quiet and smooth separation is possible and that the apparatus can be made compact and inexpensive.

  Embodiments of the present invention will be described below with reference to the drawings. This embodiment is a separation and removal device that separates and removes solids in the drainage (filtrate) of the dehydrator 50 (hereinafter referred to as a filtrate separation device), and is an example provided on the downstream side of the dehydrator. is there. FIG. 1 is a front view of the present embodiment, and FIG. 2 is an upper plan view. FIG. 3 is a flowchart showing the procedure of the controller. FIG. 4 is a time chart. FIGS. 5A to 6D are diagrams showing the states of the respective steps. In the figure, the reference numbers do not correspond because there are many parts different from the conventional apparatus (FIGS. 7 to 9).

  1 and 2, the filtrate separator 10 is provided below the dehydrator 50. The filtrate separation device 10 includes a filtrate separation tank 11 for separating solids and liquids, a storage tank 12 for storing solids, and a clarified water separation tank 13 for taking out clarified water. A storage tank 12 and a clarified water separation tank 13 are provided on both sides of the tank 11. The storage tank 12 is necessary when the separated solid content is returned to the stock solution storage tank by a pump, but can be omitted if the stock solution storage tank is located below and can be returned by natural flow. A filtrate supply pipe 15 is fixed through the side wall so that the filtrate flows horizontally to a level slightly higher than half the full liquid level of the filtrate separation tank 11. Thus, it is desirable to prevent stirring of floating solids and precipitated solids due to the dynamic pressure of the feed water. In addition, a water spray tube 17 is provided on the upstream side above the liquid surface of the filtrate separation tank 11 to eliminate bubbles that have floated together with the solid content, thereby generating ripples due to the agitation effect near the liquid surface by the air bubbles and bubble burst on the liquid surface. It is desirable to prevent the dispersion of floating solids in the liquid by flattening the liquid surface.

  On the side of the storage tank 12 adjacent to the filtrate separation tank 11 (downstream side), a guide groove 19 for smoothly discharging the floated light solid content to the storage tank 12 is provided in the upper part of the storage tank 12. The guide groove 19 and the storage tank 12 are connected to each other by pipe lines 21 and 21 via a second opening / closing valve 20. Further, the storage tank 12 is provided with a stirrer 22 for stirring the stored solid content and a liquid level gauge 23 for measuring the liquid level 12a in the storage tank. The level gauge 23 may be a conventionally known one.

  On the other hand, a clarified water separation tank 13 is provided adjacent to the other side, and the clarified water separation tank 13 communicates with an opening 27 provided at a substantially intermediate liquid level. A clarified water pipe 28 for taking out clarified water is provided at an appropriate position. The height level of the intake port 28 a of the clarified water pipe 28 is slightly lower than the water level during normal operation of the filtrate separation tank 11. It is desirable to make it low enough to allow clear water to flow smoothly through the clear water pipe 28.

  In addition, the bottom of the filtrate separation tank 11 and the bottom of the storage tank 12 are communicated with each other via pipes 31 and 31 via a first on-off valve 30, and the bottom of the storage tank 12 is further connected via a third on-off valve 32. And communicate with the outside (for example, a sludge storage tank). The first on-off valve 30, the second on-off valve 20, the third on-off valve 32, and the agitator 22 are controlled by a control device 35. The operation and control procedures of the apparatus according to this embodiment will be described below.

  In FIG. 3, step S <b> 1 fills the filtrate separation tank 11 with dehydrated filtrate, and starts operation in a state where discharge of clarified water from the clarified water pipe 28 starts. The situation at this time is shown in FIG. The amount of solids in the storage tank 12 is small, and the liquid level of the liquid level gauge 23 is below the medium level, and the first on-off valve 30, the second on-off valve 20, and the third on-off valve 32 are closed. In step S2, when the predetermined time T1 has elapsed from the start of operation, the second on-off valve 20 is opened for a time T2, and the floating solid content is sent from the guide groove 19 to the storage tank 12. The situation at this time is shown in FIG. In step S3, after closing the 2nd on-off valve 20, the 1st on-off valve 30 is opened only for time T4, and precipitation solid content is sent to the storage tank 12 from the filtrate separation tank 11. FIG. At this time, the precipitated solid content is sent out by the difference in water level head between the filtrate separation tank 11 and the storage tank 12. The situation at this time is shown in FIG. At this time, the liquid level in the filtrate separation tank 11 is somewhat lowered, and the amount of clarified water from the clarified water pipe 28 is decreased.

At this time, if the liquid level in the storage tank 12 exceeds the middle level, the stirrer 22 is rotated to mix the solid content (the solid content that has floated and the solid content that has precipitated) in the storage tank 12 (step S4). This operation (step S2 to step S4) is repeated until the liquid level in the storage tank 12 exceeds the high level. When the liquid level exceeds the high level, the third on-off valve 32 is opened to send the mixed solid content in the storage tank 12 to the outside. The situation at this time is shown in FIG. Delivery of the mixed solids continues until the liquid level reaches the bottom level. The above operation is performed until the operation is stopped. T1 (floating solid initial discharge start time) and T3 (floating solid discharge start time) are both selected from the range of (0-60) minutes, and T2 (floating solid discharge time), T4 (precipitated solid) It is desirable to select any of (minute discharge time) from the range of (0 to 60) minutes. By selecting the time, overflow from the water tank can be prevented, a difference in the water level head can be secured well, and the processing continuity of the apparatus can be secured.
FIG. 4 is a time chart showing the above flow.

  As described above, according to the present embodiment, light solids are separated and removed by using natural separation instead of the scraping blades 64 and 65 as compared with the conventional apparatus, so that eddy currents are not generated. In addition, the sedimentation and floating of the solid content is performed smoothly and smoothly, the apparatus can be made compact, the structure is simplified, the failure is less likely to occur, and the reliability is improved. In addition, the manufacturing cost is reduced, the device for driving the scraping blades 64 and 65 is not required, and the cost of the device and the running cost can be reduced.

  The embodiments and examples of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to the examples, and there are design changes and the like without departing from the gist of the present invention. Are also included in the present invention.

The whole front view of the embodiment which carried out the present invention is shown. The top view of this embodiment is shown. The flowchart of operation of this embodiment is shown. The time chart of this embodiment is shown. (A), (B) shows the situation in the process of this embodiment. (C) and (D) show the situation in the subsequent steps of this embodiment. The peripheral system of a conventional apparatus is shown. The front view of a conventional apparatus is shown. The top view of a conventional apparatus is shown.

Explanation of symbols

10 Filtrate separation device (separation removal device)
11 Filtrate separation tank (separation tank)
12 Reservation tank 13 Clear water separation tank 15 Filtrate supply pipe (drainage supply pipe)
17 Watering device 19 Guide groove 20 Second on-off valve 22 Stirrer 27 Clear water communication hole 28 Clear water pipe 30 First on-off valve 32 Third on-off valve 35 Controller (control device)

Claims (3)

In a separation / removal device that separates and removes solids contained in the effluent discharged from the dehydrator, concentrator, etc. of the sludge treatment device, the floating solids, the precipitated solids and the liquids contained in the effluents A separation tank that naturally separates the liquid, a drainage supply pipe having an outlet for the drainage in the liquid of the separation tank, a guide groove that collects floating solids, a storage tank that stores solids, and the guide And a second open / close valve provided in a connection path between the storage tank, a liquid level gauge for measuring the liquid level of the storage tank, and a clear water separation having a communication hole communicating at an intermediate liquid level of the separation tank A tank, a clarified water pipe having a water intake in the clarified water separation tank, a first on-off valve provided in a communication path between the bottom of the separation tank and the bottom of the storage tank, the bottom of the storage tank, and an external A third on-off valve provided in a communication path communicating with an external device arranged at an appropriate position, and control for controlling each on-off valve Solids separating device in the liquid, characterized by comprising the location.
The liquid level gauge detects the high level, medium level, and low level of the liquid level in the storage tank,
The controller is
When the separation and removal device is in operation and the liquid level of the storage tank is at a low level or an intermediate level, the second on-off valve is opened and closed at regular intervals to release the floating solids to the storage tank. The first on-off valve is opened for a predetermined time after the second on-off valve is closed, and the solid content settled on the bottom of the separation tank is caused to flow into the storage tank due to the difference in water level head,
When the liquid level of the storage tank is equal to or higher than the medium level, the stirrer of the storage tank is rotated to mix the floating solids and the precipitated solids,
The control according to claim 1, wherein when the liquid level of the storage tank becomes a high level, the third on-off valve is opened and the mixed solid content is sent to an external device. A device for separating and removing solid components in the liquid. The apparatus for separating and removing solid content in a liquid according to claim 1, wherein a watering device is provided above the liquid level of the separation tank.

Images