JP2556753Y2 - Horizontal decanter centrifuge - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a horizontal decanter-type centrifugal separator for separating a suspension in which a solid component and a liquid component are mixed into a solid component and a clarified liquid by using centrifugal force.

[0002]

2. Description of the Related Art A decanter-type centrifuge is used to centrifuge a suspension having a relatively high concentration into a solid component and a liquid component. Particularly, when a solid component is continuously settled and discharged. A horizontal decanter centrifuge is used. As shown in FIG. 3, the horizontal decanter-type centrifugal sedimentation machine rotates, for example, a cylindrical-conical horizontal decanter 1 and a screw conveyor 2 housed in the decanter 1 at slightly different rotation speeds in the same direction. The solid component of the suspension supplied from the supply pipe 3 into the horizontal decanter 1 is settled on the inner peripheral surface of the decanter 1 by the centrifugal force. Then, the solid component settled on the inner peripheral surface of the decanter 1 is slowly removed by utilizing the difference in the relative speed between the horizontal decanter 1 and the screw conveyor 2.
And the liquid component is discharged to the outside, and the liquid component is discharged from a liquid component discharge port 5 formed on the other end side of the decanter 1.

[0003] That is, the suspension supplied into the horizontal decanter 1 does not accumulate at the bottom of the horizontal decanter 1, but is uniformly pressed against the inner peripheral surface by its centrifugal force, so that the solid component is settled. The liquid component becomes the supernatant.
Then, the solid component is transported in the horizontal direction toward the solid component outlet 4 by the screw conveyor 2, and the liquid component is connected to the inner peripheral surface of the horizontal decanter 1 and the screw conveyor toward the liquid component outlet 5 on the other end side. 2 and flows along a spiral flow path f formed between them, whereby a solid component and a liquid component can be separated and discharged.

[0004]

However, immediately after the operation of the centrifugal sedimenter is started or when the operation is stopped, the rotation speed of the horizontal decanter 1 is low, and the centrifugal force generated by the rotation is smaller than the gravity of the suspension. . Therefore, the suspension supplied to the horizontal decanter 1 is not uniformly pressed against the inner peripheral surface thereof, but accumulates at the bottom, and the spiral flow path between the decanter 1 and the screw conveyor 2 is also divided. The water level rises without being discharged from the liquid component discharge port 5. And
The liquid component and the solid component of the suspension collected at the bottom are both transferred to the solid component outlet 4 by the screw conveyor 2 and discharged to the tank for collecting the solid component, and the liquid component is mixed with the solid component collected in the tank. Since it is soaked in water, there is a trouble that the dehydration process has to be performed again.

Therefore, the present invention does not flood the collection tank even when the rotation speed of the horizontal decanter is low, such as immediately after the operation of the centrifugal sedimentation machine or when the operation is stopped, and the water content of the collection tank is kept low. It is a technical problem to be able to recover a small amount of a solid component without water immersion.

[0006]

In order to solve this problem, the present invention is directed to a horizontal decanter and a screw conveyor accommodated in the decanter, which are rotated in the same direction at different rotational speeds and supplied into the horizontal decanter. The solid component of the suspension is settled on the inner peripheral surface of the decanter by its centrifugal force and discharged from a solid content outlet formed at one end of the decanter by a screw conveyor, and the liquid component is discharged to the other end of the decanter. In the horizontal decanter-type centrifugal sedimentation apparatus configured to discharge the liquid component from the formed liquid component discharge port, the solid component discharge port discharges the solid component to each of two solid component recovery tanks arranged side by side below the solid component discharge port. When the horizontal decanter is rotated at a speed that generates a centrifugal force greater than the gravity of the suspension, the discharge direction of the discharge port is changed to one direction. A discharge direction switching device for directing the discharge direction of the discharge port to the other collection tank when the horizontal decanter is rotated at a rotation speed that generates only a centrifugal force smaller than the gravity of the suspension toward the collection tank. Features.

[0007]

According to the present invention, the solid component discharge port is formed so as to be capable of discharging the solid component to each of two solid component recovery tanks juxtaposed below the solid component discharge port. When is rotated at a rotational speed that produces a centrifugal force greater than the gravity of the suspension, it is discharged toward one of the recovery tanks, so that solid components having a low water content are recovered in the recovery tank. Also, when the horizontal decanter is rotated at a rotation speed that generates only a centrifugal force smaller than the gravity of the suspension, such as immediately after the start of operation or when the operation is stopped, the discharge direction is switched to the other collection tank. The solid component having a high water content is recovered in the other recovery tank. Therefore, a solid component having a low moisture content discharged during normal operation and a solid component having a high moisture content discharged immediately after the start of operation or at the time of operation stop are collected in different recovery tanks.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be specifically described based on embodiments shown in the drawings. FIG. 1 is a schematic configuration diagram showing an example of the present invention, and FIG. 2 is a schematic configuration diagram showing another embodiment.

In FIG. 1, reference numeral 1 denotes a cylindrical-conical horizontal decanter in which a screw conveyor (not shown) is accommodated. For example, the horizontal decanter 1 has a slightly different rotation speed of 4000 rpm and the screw conveyor 2 has a slightly different rotation speed of 3989 rpm. Rotated in the direction. Then, the solid component of the suspension supplied into the horizontal decanter 1 is settled on the inner peripheral surface of the decanter 1 by the centrifugal force, and the solid content discharge port 4 formed at one end of the decanter 1 by the screw conveyor 2 The liquid component is discharged from a liquid component discharge port 5 formed on the other end of the decanter 1 while the solid component discharge port 4 is connected to two solid components arranged below the solid component. Each of the component recovery tanks 6 and 7 is formed to be tiltable so that the solid component can be discharged to one of the tanks.

Reference numeral 8 denotes a discharge direction switching device for switching the discharge direction at a predetermined timing by tilting the discharge port 4, and a sensor 9 for detecting the rotation speed of the horizontal decanter 1;
It comprises a comparing means 10 for comparing the number of revolutions detected by the sensor 9 with a preset value, and a cylinder 11 for swinging the discharge port 4 based on an output signal from the comparing means 10. The value set in the comparison means 10 is optimally the number of rotations at which a centrifugal force balanced with the gravity of the suspension supplied to the horizontal decanter 1 is obtained.

When the rotation speed detected by the sensor 9 is larger than the set value, the cylinder 11 is extended and the solid component discharge port 4 is tilted toward one of the recovery tanks 6, and the detected rotation speed becomes the set value. If it is smaller, the cylinder 11 is contracted, and the solid component outlet 4 is inclined toward the other recovery tank 7. Therefore, when the horizontal decanter 1 is rotated at a rotational speed that generates a centrifugal force greater than the gravity of the suspension, solid components are discharged toward one of the recovery tanks 6 and the horizontal decanter is smaller than the gravity of the suspension. When the rotation is performed at a rotation speed at which only a centrifugal force is generated, solid components are discharged toward the other recovery tank 7.

The above is an example of the configuration of the present invention, and its operation will be described below. First, when the operation of the centrifugal settling machine is started, the rotation speed of the horizontal decanter 1 is gradually increased from the stopped state. At this point, since the centrifugal force obtained by the rotation of the horizontal decanter 1 is smaller than the gravity of the suspension, not only the solid component is discharged from the solid component outlet 4 but also the liquid component flows out. Further, since the cylinder 11 of the discharge direction switching device 8 is contracted and the solid component discharge port 4 is inclined toward the recovery tank 7, the solid component having a high water content is recovered in the recovery tank 7.

Next, when the horizontal decanter 1 is accelerated and the number of revolutions reaches a set value, the centrifugal force becomes larger than the gravity of the suspension, so that the suspension is pressed against the inner peripheral surface of the horizontal decanter 1. The solid component is settled on the inner peripheral surface, and the liquid component becomes a supernatant. Then, the solid component is transferred to and discharged from the solid component outlet 4 by the screw conveyor 2, and the liquid component flows out of the liquid component outlet 5 along the spiral flow path f formed by the screw conveyor 2. At this time, the cylinder 1 of the collection tank switching device 8
1 is extended and the solid component outlet 4 is inclined toward the collection tank 6, so that the solid component having a low water content is collected in the collection tank 6.

Finally, the operation of the centrifugal sedimentation machine is paused or stopped, and when the rotation speed of the horizontal decanter 1 gradually decreases to a set value or less, the liquid component flows out of the solid component discharge port 4 again. The cylinder 11 of the switching device 8 is contracted to tilt the discharge port 4 toward the collection tank 7. This allows
The low-moisture-content solid components collected in the collection tank 6 do not become flooded, and therefore only the high-moisture-content solid components collected in the collection tank 7 need be reprocessed.

The present invention is not limited to the case where the discharge direction is switched by inclining the solid component discharge port 4, but any means may be used. For example, as shown in FIG. 2, a movable damper 12 is provided at the tip of the discharge port 4 and the damper 12 is provided.
In this case, a motor 13 for tilting the damper 12 is provided in place of the cylinder 11 of the above-described embodiment, and the rotation speed detected by the sensor 9 is larger than the set value. When the motor 13
Is rotated forward to tilt the damper 12 toward one of the recovery tanks 6. When the rotation speed detected by the sensor 9 is smaller than the set value, the motor 13 is reversed to tilt the damper 12 toward the other recovery tank 7. Let it. Alternatively, a flexible duct may be connected to the solid component discharge port 4 so that the opening at the end thereof is positioned above each of the recovery tanks 6 and 7.

[0016]

As described above, according to the present invention, according to the present invention, the solid component having a low water content discharged when the rotation speed of the horizontal decanter is high, and the rotation such as immediately after the start of operation or when stopping the operation. The solid component with a high moisture content discharged when the number is low can be collected in a separate collection tank, so that the solid component with a low moisture content obtained by centrifuging the water is not soaked. It has a very good effect that it can be recovered.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing an example of a horizontal decanter-type centrifugal sedimenter according to the present invention.

FIG. 2 is a schematic explanatory view showing cooling in another embodiment.

FIG. 3 is a sectional view showing the internal structure of a horizontal decanter-type centrifuge.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Horizontal decanter 2 ... Screw conveyor 4 ... Solid component discharge port 5 ... Liquid component discharge port 6, 7 ... Collection tank 8 .... Discharge direction switching device

Claims (1)

(57) [Scope of request for utility model registration] A suspension supplied to the horizontal decanter (1) by rotating the horizontal decanter (1) and the screw conveyor (2) stored in the decanter (1) in the same direction at different rotational speeds. The solid component is settled on the inner peripheral surface of the decanter (1) by the centrifugal force and discharged from the solids discharge port (4) formed at one end of the decanter by the screw conveyor (2), and the liquid component is decanted. In the horizontal decanter-type centrifugal sedimentation machine configured to discharge from the liquid component discharge port (5) formed on the other end side of (1), the solid component discharge port (4) is juxtaposed below the solid component discharge port. The two solid component recovery tanks (6, 7) are formed so as to be capable of discharging the solid component to each one of the two tanks so that the discharge direction can be changed.
When the horizontal decanter (1) is rotated at a rotational speed that generates a centrifugal force greater than the gravity of the suspension, the discharge direction of the discharge port (4) is directed to one of the recovery tanks (6), and the horizontal decanter (1) is rotated. A discharge direction switching device (8) for directing the discharge direction of the discharge port (4) to the other recovery tank (7) when the liquid is rotated at a rotational speed that generates only a centrifugal force smaller than the gravity of the suspension. A horizontal decanter centrifuge.