JP2002331258A - Cone-type centrifugal separator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cone-type centrifugal separator which can efficiently blow off materials to be dewatered stuck on the inner wall of a discharge room installed at the opening end side of a basket and prevent the fire of the materials to be dewatered caused by a friction heat. SOLUTION: In the cone-type centrifugal separator provided with the basket 1 rotating in one direction, and a screw 3 arranged coaxially with the basket 1 in it and rotated in the same direction as the basket 1 with the difference in rotation speed between the basket 1 and the screw 3, and in the centrifugal separator raw materials fed to between the basket 1 and the screw 3 are separated into solid and liquid; an air blowing mechanism 6 is arranged in the discharge room 8 installed at the opening end side 15 of the basket 1 in order that the materials to be dewatered D stuck on the inner wall of the discharge room 8 are blown off by blowing air to the discharge room 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cone-type centrifugal separator used for solid-liquid separation, and more particularly, to a method for efficiently removing dehydrated substances adhering to the inner wall of a discharge chamber provided at the open end of a basket. The present invention relates to a cone-type centrifugal separator capable of preventing ignition due to frictional heat of a dehydrated substance.

[0002]

2. Description of the Related Art Conventionally, in a sewage treatment plant, a treatment method has been put to practical use in which sediment separated from sewage is fried with oil, and the fried residue is further solid-liquid separated by a centrifugal separator. .

As shown in FIG. 7, a cone-type centrifugal separator used in this processing method has a conical bottomed basket 1 in which a number of slits are formed and an inner peripheral surface of the basket 1. A screen 2 provided, a conical screw 3 having a screw blade 32 on an outer peripheral surface provided inside the screen 2, and provided so as to substantially coincide with the central axis of the basket 1, and face the bottom of the basket 1. A supply pipe 4 which is opened through the inner surface of the basket 1, ie, the screen 2 and the screw 3.
And a distributor 5 extending to the screw 3 for guiding the space to the space formed between the screw 3 and the screw 3.

In this cone type centrifugal separator, the basket 1 and the screw 3 are connected to the respective rotating shafts 11,
While rotating at a required rotation speed (normally, the rotation speed of the screw 3 is set slightly higher than the rotation speed of the basket 1) by an electric motor (not shown) via 31, the residue is supplied. The water is supplied from the pipe 4 to the inner peripheral surface of the basket 1 via the distributor 5, that is, the space formed between the screen 2 and the screw 3. As a result, the residue supplied to the space formed between the screen 2 and the screw 3 is centrifuged to
The liquid component passes through a screen 2 having a myriad of fine holes, and then is discharged into a separation liquid tank 7 through a slit formed in the basket 1. On the other hand, screen 2
The solid components of the residue trapped by the screw 3 are screw blades 32 of the screw 3 rotating with a slight difference from the basket 1.
Is transported toward the open end of the basket 1 and is discharged into the discharge chamber 8 as a dehydrated substance D.

[0005]

By the way, in a processing method in which sediment separated from sewage is fried in oil, and the fried residue is further solid-liquid separated by a centrifugal separator,
The dehydrated substance of the residue fried with oil contains a cotton-like substance, and the cotton-like substance (hereinafter, referred to as “dehydrated substance D”) contained in the dehydrated substance adheres to the inner wall of the discharge chamber 8. In this case, the dehydrated substance D adhered gradually grows and comes into contact with the open end of the rotating basket 1 or the like.

The present invention has been made in view of the above-mentioned problems of the conventional cone type centrifugal separator, and efficiently removes dehydrated substances adhering to the inner wall of a discharge chamber provided on the open end side of the basket, thereby removing the dehydrated substances. An object of the present invention is to provide a cone-type centrifugal separator capable of preventing ignition due to frictional heat.

[0007]

To achieve the above object, a cone-type centrifugal separator according to the present invention is provided with a basket rotating in one direction and coaxially disposed in the basket to reduce a rotational speed difference from the basket. A screw having the same direction and having a screw, and in a cone-type centrifuge that performs solid-liquid separation of the raw material supplied between the basket and the screw, in a discharge chamber provided on the open end side of the basket, air is supplied. An air ejection mechanism is provided for removing dehydrated substances adhered to the inner wall of the discharge chamber by ejection.

This cone type centrifugal separator has an air ejection mechanism for sweeping dewatering substances adhered to the inner wall of the ejection chamber by ejecting air into an ejection chamber provided on the open end side of the basket. Before the dewatering substance adhering to the inner wall of the discharge chamber grows, air can be blown out from the air ejection mechanism to remove the dewatering substance adhering to the inner wall of the discharge chamber. , Which
It is possible to prevent the dehydrated substance from growing until it comes into contact with the open end of the basket, thereby preventing the dehydrated substance from being ignited by frictional heat.

In this case, the air ejection mechanism can be configured to intermittently eject air every few seconds.

[0010] This makes it possible to apply an intermittent impact force to the dewatered substance adhered to the inner wall of the discharge chamber provided on the open end side of the basket, thereby more effectively removing the dewatered substance. In addition, the compressor can perform labor-saving operation.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a cone-type centrifuge according to the present invention will be described below with reference to the drawings.

1 to 6 show an embodiment of a cone type centrifugal separator according to the present invention. The basic structure of this cone-type centrifugal separator is the same as that of a conventional cone-type centrifuge. As shown in FIG. A conical basket 1 with a bottom, a screen 2 disposed on the inner peripheral surface of the basket 1 and fixed at both ends to the basket 1 by fixing members 13 and 14, and an outer peripheral surface disposed on the inner side thereof. The conical screw 3 having the screw blades 32 is disposed so as to substantially coincide with the central axis of the basket 1.
And a distributor 5 extending to a screw 3 for guiding the residue supplied from the supply pipe 4 to the inner peripheral surface of the basket 1.

The cone type centrifuge is shown in FIG.
As shown in FIG. 4, air is blown into the dehydration substance discharge chamber 8 provided on the open end 15 side of the basket 1 to blow off the dehydration substance D attached to the inner wall of the discharge chamber 8. The ejection mechanism 6 is provided.

The air jetting mechanism 6 is not particularly limited, but jetting nozzles 61 installed at two places above the dewatering substance discharge chamber 8 provided on the open end 15 side of the basket 1.
And an air supply device 62 for supplying air to the ejection nozzles 61, and a compressor (not shown) for supplying compressed air to the air supply device 62.

The ejection nozzle 61 is provided so as to penetrate the upper wall 81 of the discharge chamber 8 as shown in FIG.
The tip portion 61a is bent at an angle of 10 to 30 degrees or the like, and can be fixed to the upper wall 81 of the discharge chamber 8 at an arbitrary rotation angle so that the orientation of the tip portion 61a can be set arbitrarily. .

As shown in FIG. 5, an air supply device 62 includes an air tank 63 for storing air from the compressor at a constant pressure.
And a pipe 64 from the air tank 63 to the ejection nozzle 61
And a controller 66 for controlling the opening and closing operation of the solenoid valve 65.

The controller 66 allows the air ejection mechanism 6 to eject air intermittently. In this embodiment, the opening time is a few seconds to one second (for example, 0.5 seconds). Closing time: After repeatedly opening and closing the solenoid valve 65 several times (for example, 6 times) in several seconds (for example, 5 seconds), an interval of several minutes (for example, 3 minutes) is provided. The operation and the interval are repeated as one cycle. As described above, the air is ejected from the air ejection mechanism 6 intermittently and at appropriate intervals so that the open end 15 of the basket 1 can be opened.
The dewatering substance D adhered to the inner wall of the discharge chamber 8 provided on the side can be effectively wiped off, and the compressor can be operated in a labor-saving manner.

Next, the operation of the cone type centrifugal separator of the present embodiment will be described. The cone-type centrifugal separator rotates the basket 1 and the screw 3 at a required number of revolutions by a motor (not shown) via respective rotating shafts 11 and 31, and removes the residue from the supply pipe 4 through the distributor 4. 5 and the inner peripheral surface of the basket 1 through the residue discharge port 33;
That is, the ink is supplied to the space formed between the screen 2 and the screw 3. Thereby, the residue supplied to the inner peripheral surface of the basket 1 causes the liquid component to pass through the screen 2 having innumerable fine holes by centrifugal force,
Next, the liquid is discharged into the separation liquid tank 7 through the slit 12 formed in the basket 1. On the other hand, the solid component captured by the screen 2 is transferred toward the open end 15 of the basket 1 by the action of the screw blade 32 of the screw 3 rotating at a slight difference from the basket 1, and becomes a dewatering substance and becomes a discharge chamber. 8 is discharged.

By the way, the sediment separated from the wastewater is fried in oil, and the fried residue is solid-liquid separated by a cone centrifuge.
The dehydrated substance D easily adheres to the inner wall of the discharge chamber 8 provided on the open end 15 side of the basket 1, and the adhered dehydrated substance D grows gradually and comes into contact with the open end of the rotating basket 1. There is a risk that an accident may occur due to fire.

For this reason, in the cone-type centrifugal separator of the present embodiment, the air is ejected from the air ejection mechanism 6 provided in the ejection chamber 8 provided on the open end 15 side of the basket 1 so that the discharge chamber 8 is The dehydrated substance D adhering to the inner wall is wiped off. As described above, before the dehydrated substance D attached to the inner wall of the discharge chamber 8 grows, the air is ejected from the air ejection mechanism, so that the dehydrated substance D attached to the inner wall of the discharge chamber can be washed off. Thus, the dehydrated substance D
Can be prevented from growing until it contacts the open end of the basket, and the dehydrated substance D can be prevented from igniting due to frictional heat.

Although the cone type centrifugal separator of the present invention has been described based on the embodiment, the present invention is not limited to the configuration described in the above embodiment. For example, the jet nozzle 61 may be fixed. Instead, a drive mechanism that swings or rotates the ejection nozzle 61 within a predetermined angle range is provided (this makes it possible to widen the ejection direction of the air, and to provide the basket 1 at the open end 15 side). The configuration can be appropriately changed within a range not departing from the purpose, such as removing the dehydrated substance D attached to the inner wall portion of the provided discharge chamber 8 more effectively.)

[0022]

According to the cone type centrifuge of the present invention,
An air ejection mechanism is provided in the discharge chamber provided on the open end side of the basket to blow off dehydrated substances adhered to the inner wall of the discharge chamber by blowing air. By ejecting air from the air ejection mechanism before the dehydrated substance attached to the portion grows, the dehydrated substance attached to the inner wall of the discharge chamber can be wiped off. It is possible to prevent the dehydrated substance from igniting due to frictional heat before it grows until it comes into contact with the material. And since this cone-type centrifuge can remove the dehydration substance adhered to the inner wall portion of the discharge chamber while operating the cone-type centrifuge, the entirety including the dehydration treatment step by the cone-type centrifuge is performed. Since the dehydrated substance can be removed without affecting the processing steps, the overall processing efficiency can be improved.

Further, the air ejection mechanism is configured to intermittently eject air every few seconds, so that the dewatering substance attached to the inner wall of the discharge chamber provided on the open end side of the basket is intermittent. By applying an impact force, the dewatering substance can be more effectively wiped off, and the compressor can be operated in a labor-saving manner.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing an embodiment of a cone-type centrifuge according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a plan view of the same.

FIGS. 4A and 4B show an ejection nozzle, wherein FIG. 4A is a cross-sectional view showing an attached state, FIG. 4B is a plan view of the same, FIG. (e) is a sectional view showing a modification of the ejection nozzle.

FIG. 5 is a partial cross-sectional front view showing an air supply device.

FIG. 6 is an enlarged sectional view showing a cone portion of the cone type centrifuge.

FIG. 7 is a front sectional view showing an entire conventional cone-type centrifuge.

[Explanation of symbols]

 Reference Signs List 1 basket 11 rotation shaft 12 slit 15 open end 2 screen 3 screw 31 rotation shaft 32 screw blade 33 residue discharge port 4 supply pipe 5 distributor 6 air ejection mechanism 61 ejection nozzle 62 air supply device 63 air tank 64 pipe 65 electromagnetic valve 66 controller 7 Separation liquid tank 8 Discharge chamber D Dehydration substance (cotton-like substance)

Continued on the front page (72) Inventor Hiroki Motoyama 15-18, Nagisaminamicho, Hirakata-shi, Osaka F-term (reference) 4D057 AA11 AB01 AC02 AC06 AD01 AE03 AF03 BA36 BC05 BC16

Claims (2)

[Claims] 1. A basket rotating in one direction, and a screw coaxially disposed in the basket and rotating in the same direction with a difference in rotation speed from the basket, and supplied between the basket and the screw. In a cone-type centrifuge that performs solid-liquid separation of raw materials, air is blown into the discharge chamber provided at the open end of the basket to blow off dehydrated substances attached to the inner wall of the discharge chamber. A cone-type centrifuge having a mechanism. 2. The cone-type centrifugal separator according to claim 1, wherein the air ejection mechanism is configured to eject air intermittently every several seconds.