JPH0669640B2 - Dehydration transport method for screen ▲ screen ▼ - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is a screen for transporting screen residue scraped and removed from a water channel of a sewage treatment plant, a pump station, etc. to a predetermined high position while dehydrating it in a duct. The present invention relates to a method for dehydrating and transporting residue.

[Conventional technology]

Conventionally, the screen residue collected from a sewage treatment plant has a high water content, and it is troublesome to dispose the collected screen waste into a hopper or an incinerator for subsequent treatment. Therefore, it is necessary to dehydrate the collected screen residue until the water content falls below a predetermined water content. Conventionally, dehydration of this screen residue is carried out by a dehydrator, and the screen residue after dehydration is carried by an unloader to a hopper or an incinerator.

Further, Japanese Patent Publication No. 46-26285 discloses a method in which a screen residue is supplied into a closed duct, pressure-dehydrated, and then pressure-fed.

[Problems to be Solved by the Invention]

In the method of dehydrating the screen residue with a dehydrator and then transporting it to a predetermined position with a transporter, the equipment installation space becomes large and it is difficult to seal the other equipment for maintenance and inspection. Is open type. For this reason, the work environment is deteriorated due to the scattering of foul odors.

On the other hand, the method of dehydrating under pressure in a closed duct and transporting it as it is is excellent. However, a part of this transport duct is generally bent due to the lift of the dehydration screen residue.

Moreover, in recent years, the sand basin has become deeper, and it is necessary to carry the screen residue with a high lift and long distance, but it is difficult to satisfy the conditions of bending of the transfer duct, long distance, and high lift by the conventional method.
There is an inevitable limit to the transportation distance and lift.

An object of the present invention is to allow the screen residue after dehydration to be transferred smoothly and for a long distance.

[Means for Solving the Problems]

The present invention has been made in order to achieve the above-mentioned object, and is pressurized dewatering mainly having a plunger at the lower end of a screen residue dewatering / transporting duct having a required diameter and a required head with a dewatering screen residue discharge port formed at the upper end. In a method for dehydrating and transporting screen residue by means of a screen residue dehydrator equipped with a means, the back pressure plate is closed and the plunger is reciprocated one or a required number of times to perform predetermined dehydration, and then locked at the plunger forward position,
Moreover, the gist is that high-pressure air is blown into the transfer duct immediately after the back pressure plate, and the screen residue after dehydration is transferred by this high-pressure air pressure flow.

In addition, the screen residue dehydrator is equipped with a dehydration screen residue discharge port at the upper end and has a required diameter and a required head. In the transportation method, the back pressure plate is closed and the plunger is reciprocated once or a required number of times to perform predetermined dehydration, and then the plunger is locked at the forward position, and the valve provided at the upper end of the transportation duct is closed and the duct is closed. The gist is that negative pressure is generated in the duct by sucking with a blower from the inside of the upper part, and the screen residue after dehydration is sucked and conveyed.

Further, the screen residue dehydrator using a screen residue dehydrator equipped with a pressurized dehydration means mainly composed of a plunger at the lower end of the screen residue dehydration / conveying duct having a required diameter and a required lift with a dehydration screen residue discharge port formed at the upper end. In the transportation method, the back pressure plate is closed and the plunger is reciprocated once or a required number of times to perform a predetermined dehydration, and then the plunger is locked at the forward position, and the valve provided above the transportation duct is closed and the duct is closed. While sucking with a blower from the top,
The gist is that high-pressure air is blown into the transfer duct immediately after the back pressure plate, and the screen residue after dehydration is transferred by suction from the upper part of the duct and high-pressure air flow from the lower part of the duct.

〔Example〕

 The present invention will be described below with reference to the illustrated embodiments.

The screen residue collected from the sewage treatment plant, the pump station, etc. is continuously or intermittently transferred, and the screen residue dehydrator 1 is arranged below the end of the transfer means, and is supplied to the upper part of the dehydrator 1. The hopper 2 of is arranged. This hopper 2 is provided above the dehydrating section 3 of the dehydrator, and
The dehydrating unit 3 is composed of a cylindrical main body 31 whose one end is bent upward at a required angle, and a pressure dehydrating means 32 mainly composed of a plunger housed in a horizontal portion of the main body 31.
A hydraulic cylinder 32a is used as the pressurizing / dehydrating means 32, and a plunger 32b is provided in the cylinder 32a, and the hopper 2 is arranged above the front end position where the plunger 32b is retracted. The outlet of the lower part of the hopper 2 is made slightly shorter than the stroke of the plunger 32b, and the pressurizing part 4 is provided at a position slightly ahead of the position where the plunger 32b projects. And this body
In 31, a dehydration hole 34 is formed from a lower position of the hopper 2 to a lower position of the pressurizing unit and a position beyond this pressurizing position,
The water contained in the screen residue is dehydrated from the time when the water content is supplied from the hopper into the main body to the pressure dehydration and then drained to the outside of the main body.

The pressurizing unit 4 is constructed so as to squeeze the screen residue by the pressurizing and dehydrating means 32 and raise the applied pressure to a value required for dehydration. It is narrowed between the main body 31 and the transport duct 5 on the curved discharge side.

The pressurizing unit 4 is composed of a back pressure plate 6 which is swung by a pressurizing cylinder 6S in a bent portion of the duct 5 or the body 31, and a cylindrical draining screen 7. As shown in FIG. 4, this drainage screen 7 has flanges 71a and 71b at both ends, and a plurality of screen bars 72 are installed between the two facing flanges 71a and 71b at a predetermined pitch. The flanges 71a, 71b are integrally connected to the flange 33 provided on the main body 31 and the flange 51 provided on the duct side by pins or bolts so that they can be easily attached and detached during cleaning.

The cross-sectional shape of the dewatering screen residue transfer duct 5 may be various shapes such as a quadrangle and a semicircle in addition to the cylindrical shape. Further, whether the duct 5 has the same diameter from the starting end side to the terminating end side or has the tapered shape in which the terminating end side has a large diameter is appropriately determined according to the conveying and lifting distance. In order to carry the dehydrated screen residue in the duct with low friction, a low friction material may be attached or applied in the duct.

In addition, the air outlet is provided in the lower portion of the transport duct 5, for example, at a position passing through the back pressure plate 6 or at an advanced position of the plunger,
Air of a required pressure compressed by the compressor C is stored in this pressure outlet in the pressure accumulator B, and piping from this pressure accumulator B via a valve V is performed. By opening the valve V, the required high pressure air is discharged from the air outlet. Blow into the transfer duct. As a result, the pressure in the lower part of the duct is increased, and the dehydrated screen residue is conveyed by this pressurized air flow so as to be pushed up in the duct, and is dropped and supplied into the hopper H through the upper end opening of the duct.

Further, the upper end of the transport duct 5 is bent slightly downward and has a large diameter, a valve 9 is provided at the end of the duct so as to be openable and closable, and a blower 8 is provided at this downward large diameter bent portion.
Is provided to absorb the air in the upper chamber of the duct to create a negative pressure.

In the screen residue dewatering machine configured as described above, the screen residue normally fed from the hopper into the dewatering section 3 is dewatered by the plunger 32b performing forward and backward reciprocating motions at regular intervals and pushed out to the upper part of the back pressure plate. At this time, the back pressure plate 6 is biased in the closing direction by a predetermined force. It is possible to improve the dehydration effect by changing the speed such that the forward / backward movement speed of the plunger is fast in the initial stage of forward movement, slow in the vicinity of the final end, and fast in backward movement.

When a certain amount of the screen residue dehydrated in this way is accumulated on the upper part of the back pressure plate, the plunger is stopped at the advanced position and the valve V is opened to discharge the high pressure air.
When it is supplied into the lower part of the duct, the internal pressure of the lower part of the duct becomes higher, and the screen residue after dehydration is raised and conveyed by this air pressure, and falls into the hopper H from the upper end of the duct.

Instead of the high-pressure air outlet 100, as shown in FIG. 3A, a high-pressure air pipe 100b having a high-pressure air outlet 100a at the lower portion of the duct is slidably provided so that it can be inserted into the lower portion of the duct. Alternatively, as shown in FIG. 3 (B), a high pressure air outlet 100c is provided in the back pressure plate 6, and a high pressure air pipe 100d is connected to the inside of the back pressure plate 6 to supply high pressure air into the lower portion of the duct. Can be configured to.

In this pneumatic conveying type, when the upper valve 9 is left open, the screen residue pushed down by air pressure in the conveying duct and conveyed is sequentially supplied into the hopper. In this method, the gate 91 of the hopper can be used instead of the valve 9. In this case, suction is performed from above the hopper body.

Further, when a negative pressure is generated by sucking the inside of the transport duct with a blower, the valve 9 is closed, the blower is driven, and the screen dust sucked from the duct upper portion is dropped onto the valve 9 and temporarily stored. After that, by opening the valve 9, the material is dropped and supplied into the hopper at once.

The screen dust can be conveyed by a combination of suction of the upper part of the duct by this blower and blowing of high-pressure air into the lower part, and a screen dust suction prevention device such as a wire mesh may be provided at the suction port.

〔The invention's effect〕

According to the present invention, the screen residue in the transport duct dehydrated by the forward / backward movement of the plunger is blown with high-pressure air from the lower part of the duct or negative pressure sucked with a blower from the upper part of the duct, and further, the lower part of the duct is pressurized and the upper part is removed. Since the negative pressure allows the air to be pushed up and carried by the air flow, the carrying duct length is long, and the carrying can be carried smoothly without clogging the duct even at a high lift.

[Brief description of drawings]

FIG. 1 is an overall external view, FIG. 2 is a vertical sectional front view of a screen residue dehydrator, FIG. 3 is an explanatory view of an outlet, and FIG. 4 is a perspective view showing a drainage screen. 2 is a hopper, 3 is a dehydrator, 3H is an inlet, 31 is a main body, 32
a is a hydraulic cylinder, 32b is a plunger, 4 is a pressurizing unit,
5 is a duct, 6 is a back pressure plate, 7 is a drain screen, C is a compressor, B is a cover pressure device, V is a valve, and 8 is a blower.

Continuation of front page (56) Reference JP-A-3-268897 (JP, A) JP-A-3-268896 (JP, A) JP-A-3-238199 (JP, A) JP-A-3-234397 (JP , A) Japanese Unexamined Patent Publication No. 3-181400 (JP, A) Actually opened 55-49894 (JP, U) Actually opened 57-16292 (JP, U) JP-B 46-26285 (JP, B1) JP-B 57-43049 (JP, B2) Actual public Sho-56-34874 (JP, Y2) Actual public Sho-59-14068 (JP, Y2)

Claims (4)

[Claims] Claim: What is claimed is: 1. A screen by a screen residue dehydrator equipped with a pressurized dehydration means mainly consisting of a plunger at the lower end of a screen residue dehydration / transporting duct having a required diameter and a required lift with a dehydration screen residue discharge port formed at the upper end. In the method of dehydration transfer of residue, after closing the back pressure plate and reciprocating the plunger one or a required number of times to perform the predetermined dehydration, the plunger is locked at the forward position, and the high pressure is applied to the transfer duct immediately after the back pressure plate. A method for dehydrating and transporting screen residue, characterized in that air is blown out and the screen residue after dehydration is transported by this high-pressure pneumatic flow. 2. A screen by means of a screen residue dehydrator equipped with a pressurized dehydration means mainly consisting of a plunger at the lower end of a screen residue dehydration / conveying duct having a required diameter and a required lift with a dehydration screen residue discharge port formed at the upper end. In the drainage transport method of residue, after closing the back pressure plate and reciprocating the plunger once or a required number of times to perform a predetermined dehydration, the plunger is locked at the plunger forward position, and a valve provided at the upper end of the transport duct is used. A method for dehydrating and transporting screen residue, characterized in that a negative pressure is generated in the duct by suctioning with a blower from the inside of the duct while closing and the screen residue after dehydration is suctioned and transported. 3. The method for dehydrating and transporting screen residue according to claim 2, wherein when sucking from the upper part of the duct with a blower, the air is sucked from the lower part of the duct. 4. A screen by means of a screen residue dehydrator equipped with a pressurized dehydration means mainly consisting of a plunger at the lower end of a screen residue dehydration / conveying duct having a required diameter and a required head with a dehydration screen residue discharge port formed at the upper end. In the drainage transport method of residue, after closing the back pressure plate and reciprocating the plunger once or a required number of times to perform a predetermined drainage, the plunger is locked at the forward position, and the valve provided above the transport duct is used. While closing and sucking with a blower from the upper part of the duct, high-pressure air is blown into the transport duct immediately after the back pressure plate, and the screen residue after dehydration is sucked from the upper part of the duct.
A method for dehydrating and transporting screen residue, characterized in that it is transported by a high-pressure pneumatic flow from the lower part of the duct.