JPH06104166B2 - Screen residue dewatering conveyor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a screen for conveying the inside of a conveying pipe after squeezing and collecting the screen residue that has been scraped up from a sewer or the like such as a wastewater treatment plant or a pumping station. More specifically, the present invention relates to a screen residue dehydration / conveyance device capable of reliably dehydrating a screen residue and conveying it over a long distance.

[Conventional technology]

Conventionally, as this type of dewatering / conveying device, those described in JP-B-57-43049 and JP-A-1-117118 are known.

All of these devices dehydrate and convey the screen residue by pushing it upwards from the bottom of the pipe that has an upslope, because most of the dehydration and conveyance of the screen residue or the front process is performed inside the pipe. It has the advantages that the odor of the screen residue does not leak to the surrounding environment and the screen residue does not come in contact with the eyes of workers such as workers.

[Problems to be Solved by the Invention] However, in any of these conventional techniques, the pipes are formed of pipes having the same diameter. What is disclosed in Japanese Patent Laid-Open No. 1-117118 is a stepped tube, but even in the stepped tube, each step has the same diameter. As a result, as is clear from the findings of the inventor, which will be described later, the force required for conveyance, that is, pushing up, increases as the pushing up is repeated, and there is a risk that the conveying path will eventually be blocked.

The present invention has been made by clarifying the above-mentioned problems from the cause of its occurrence, and releases the internal pressure of the screen residue rising on the conveying path, thereby reducing the pushing force required for conveying, and also the conveying path. An object of the present invention is to provide a screen residue dewatering and conveying device that prevents clogging of the screen residue inside.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the present invention is a screen residue dewatering and conveying device that conveys a screen residue collected from a sewer or the like in a carrier pipe after squeezing and dehydrating the screen residue, and a pressurizing unit and a downstream side of the pressurizing unit. And a swingable back pressure plate that narrows the cross-sectional area of the transport path to apply a constant back pressure to the screen residue to dehydrate the back pressure portion, and is connected downstream from the back pressure portion. The gist of the present invention is that it comprises a taper-shaped upward conveying pipe whose cross-sectional area on the downstream side is sequentially enlarged.

[Action]

The screen residue supplied to the pressurizing section is placed downstream of this pressurizing section, and a certain back pressure is applied by the swingable back pressure plate. Squeezed and dehydrated. The screen residue that has been squeezed and dehydrated is sent out to a transfer section consisting of a taper-shaped transfer tube in which the cross-sectional area on the downstream side, which is continuously provided on the downstream side of this back pressure section, is enlarged. Since it is formed in a tapered shape with the cross-sectional area on the downstream side gradually increasing, it is possible to reduce the pressure caused by the compressed screen residue trying to spread toward the pipe wall direction of the carrier pipe, and to reduce the screen residue. It becomes possible to convey a long distance by power.

Here, the findings of a finder or the like regarding the behavior of the squeezed screen residue will be described.

When the screen residue is conveyed using a straight pipe conveying path, the compressed screen residue tends to spread toward the pipe wall of the conveying pipe, and the weight of the upper screen residue remains unchanged during the pushing up process. It covers the residue. As a result, as shown in FIG. 5 (a), the pressure on the side wall surface also becomes higher in the lower screen residue.

Here, the increase in the pressure on the side wall surface directly increases the frictional force between the wall surface and the screen residue.

Therefore, as shown in the state of FIG. 5 (b) in which the push-up has been completed in several steps, the internal pressure once generated is not released, but proceeds as it is.

Then, by repeating the pushing, the internal pressure is relaxed, that is, the frictional force of the wall surface gradually increases, and eventually the frictional force becomes larger than the pushing-up force to close the wall.

On the other hand, if a taper-shaped conveyance path is used in which the cross-sectional area on the downstream side is gradually increased, the internal pressure generated by the squeezing disappears by expanding laterally as the screen dust is pushed upward. . Specifically, when the diameter of the transport path is increased by about 3% of the moving distance, the pressure on the wall surface is released.

Then, no matter how many times the extrusion is repeated, the initial state shown in FIG. 5 (c) and the state after the repetition shown in FIG. 5 (d) are the same, and the resistance does not increase.

〔Example〕

 The present invention will be described below based on the illustrated embodiments.

In the figure, 1 is a hopper of a screen residue dewatering / conveying device, which is continuously or intermittently supplied with screen residue scraped and collected from a sewage treatment plant, a water channel such as a pump,
The screen residue is supplied to the pressurizing unit A via the hopper 1.

The hopper 1 is provided above the pressurizing unit A, and the pressurizing unit A is provided with a hydraulic cylinder 3 or a screw for squeezing and dewatering the screen residue supplied from the hopper 1. Arrange the device 2. The hydraulic cylinder 3 is supported by a cylinder bracket 3a, and the rod end of the hydraulic cylinder 3 is provided with a pressurizing piston 3b. By operating the cylinder 3, the pressurizing piston 3b moves within the pressurizing portion A. The screen residue supplied from the hopper 1 as it moves back and forth is intermittently squeezed to be dehydrated. Therefore, a large number of drainage holes 2H, 2H ... Are drilled in the peripheral surface of the cylindrical pressurizing portion A corresponding to the lower position of the hopper 1, and a drainage screen 4 is provided downstream of the hopper 1 as necessary. It is provided.

On the downstream side of the tubular pressurizing unit A equipped with the pressurizing device 2,
A tubular back pressure portion B is connected, and a transport portion C having a tubular transport pipe 9 having a downstream cross-sectional area sequentially enlarged is connected to the back pressure portion B.

An opening is provided in a part of the tubular tube 5 in the back pressure part B, a back pressure plate 6 is fitted in the opening and is swingably supported, and the back pressure plate 6 is supported via a lever 7 to the back pressure plate 6. A pressure hydraulic cylinder 8 is provided, and by operating this cylinder 8, the back pressure plate 6 is inserted into the cylinder to narrow the cross-sectional area of the tubular tube 5 and apply a required back pressure to the screen residue. The back pressure can be adjusted by the cylinder 8.

In this case, the internal pressure in the tubular tube 5 generated by the back pressure plate 6 is approximately proportional to the dehydration rate, so that the desired dehydration can be reliably performed.

Although a predetermined force is applied to the back pressure plate 6 by the back pressure hydraulic cylinder 8 via the swing shaft and the lever 7, a spring or the like may be used. Also, the opening of the back pressure plate is set to a predetermined size,
Instead of the back pressure hydraulic cylinder 8, a method of fixing with a bolt may be adopted.

The transport section C is mainly composed of a tapered transport tube 9 whose cross-sectional area on the downstream side is sequentially enlarged. The transport tube 9 is arranged vertically or inclined, and its shape is cylindrical.
Alternatively, a shape such as a rectangle is adopted. When the carrier pipe 9 is cylindrical, it is advantageous in strength, and the uniformity of the pressure is slightly inferior to that of the rectangular pipe as compared with the cylindrical pipe, but the operability,
Excellent in cleanability.

Furthermore, in order to carry the screen residue after dehydration more smoothly, a low friction material may be attached or applied to the inner surface of the tube.

Next, the operation of the screen residue dewatering and conveying device will be described.

The screen residue is pushed into the pressurizing section A by the forward movement of the pressurizing piston 3b, and the pressurizing force by the back pressure hydraulic cylinder 8 is applied, and the internal pressure is generated by the resistance of the back pressure plate 6 held.
The water in the screen residue is separated and discharged from the water drain hole 2H and the water drain screen 4.

Further, the screen residue that has been dehydrated and has reduced fluidity causes the back pressure plate 6 to oscillate by operating the back pressure hydraulic cylinder 8 and expands the cross-sectional area of the tubular tube 5 to increase the back pressure portion B.
Pass through. The dehydrated screen residue that has passed through the back pressure part B is
The conveying section C having a taper-shaped upward conveying pipe 9 in which the downstream cross-sectional area that is continuously provided on the downstream side of the back pressure section B is sequentially enlarged is lifted and discharged to the hopper. As a result, stable dewatering and transport can always be performed even if the properties and the lifting height of the screen residue change.

〔The invention's effect〕

According to the present invention, since the conveying pipe is formed in a tapered shape in which the downstream cross-sectional area is sequentially enlarged, the pressure exerted on the conveying pipe wall direction by the screen residue whose fluidity has been reduced by being squeezed and dehydrated. Therefore, the transport resistance can be reduced, the screen dust can be transported for a long distance with a small power, and the screen dust can be prevented from being blocked in the transport path.

[Brief description of drawings]

FIG. 1 is an enlarged cross-sectional view of a main part of a screen residue dehydration / transportation device of the present invention, FIG. 2 is a cross-sectional view of a back pressure part, FIG. 3 is a schematic explanatory view of the whole, and FIG. 5 and 5 are cross-sectional explanatory views of the carrier pipe. 2 is a pressure dehydrator, 3 is a hydraulic cylinder, 3b is a piston,
4 is a drain screen, 5 is a pipe, 6 is a back pressure plate, 8 is a hydraulic cylinder for back pressure, and 9 is a transfer pipe.

Claims (1)

[Claims] 1. A screen residue dewatering / conveying device for conveying the inside of a conveying pipe after squeezing and dewatering a screen residue collected from a sewer or the like, which is provided with a pressurizing unit and is disposed downstream of the pressurizing unit. A back pressure part that narrows the cross-sectional area of the transport path by a movable back pressure plate to apply a constant back pressure to the screen residue to dehydrate it, and a cross-sectional area of the downstream side that is connected downstream of the back pressure part. And a transport section having a taper-shaped upward transport tube, which is enlarged in sequence.