JPH0822395B2 - Continuous centrifuge - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a pool-type solid substance washing type continuous centrifuge for washing solid substances in a decanter continuous centrifuge (hereinafter referred to as "continuous centrifuge"). It concerns a separator.

[Conventional technology and its problems]

Continuous centrifuges are widely used because they can perform solid-liquid separation continuously and efficiently.

However, this continuous centrifuge removes the mother liquor adhering to the solid matter with a washing liquid because of sedimentation separation due to the difference in specific gravity.For so-called solid matter washing, the washing effect is that of another filtration type centrifuge. It had the disadvantage that it was inferior to.

By the way, as a method for washing solids in a continuous centrifuge, for solids that have been transported to the dewatering zone,
The cleaning liquid was sprinkled through the cleaning liquid hole at the center of rotation of the screw.

 However, this method has the following drawbacks.

The washing solution was not evenly and evenly sprinkled on all solids.

Looking at individual solids, a part of the solids was washed by the washing liquid, but it was difficult for the washing liquid to spin and wash the entire surface of the solids.

Even so, when the solid particles are coarse, the cleaning liquid easily passes between the particles, so that the particles come into contact with the surface of the particles to some extent and a temporary cleaning effect is obtained, but it is difficult to obtain a uniform and stable cleaning effect, and fine particles are fine. With respect to the particles, the resistance of the cleaning liquid passing between the particles was large, and therefore most of the cleaning liquid flowed on the surface of the solid layer, and the cleaning effect could hardly be obtained.

For this reason, as a commonly-used solid cleaning method,
The solid matter that was once separated and discharged by the continuous centrifuge is stirred with the washing solution in the washing solution tank to re-slurry it, and then supplied to the continuous centrifuge again for solid-liquid separation, thereby obtaining a uniform and stable washing effect. I was allowed to.

[Means for solving problems]

The present invention does not wash the solids in the washing liquid tank, but creates a pool portion of the washing liquid corresponding to the washing liquid tank in the continuous centrifuge, and continuously immersing the separated and drained solids in the pool portion, It is designed to give a cleaning effect similar to that of cleaning solids in a cleaning liquid tank (hereinafter referred to as pool type solids cleaning), has a ball and a screw, and is equipped with a cleaning liquid supply mechanism for cleaning solids. In the centrifuge, the first cone ball for separating the mother liquor from the solid matter, and the second cone ball for washing the solid matter, the inner diameter of the base end of the second cone ball is the first cone The inner diameter of the tip of the second conical ball is made larger than the inner diameter of the tip of the second conical ball, and the inner diameter of the tip of the second conical ball is made smaller than the inner diameter of the tip of the first conical ball. Tip of Forming a cleaning pool between the end faces, was supplied to the washing pool washings were Yue flow to the first conical ball side, characterized in that so as to discharge with the mother liquor.

〔Example〕

Hereinafter, the continuous centrifuge of the present invention will be described based on the illustrated embodiments.

In the drawing, 1 is a cylindrical ball, 2 is a first conical ball formed on the inner peripheral portion of the tip of the cylindrical ball 1, and 3 is at the tip of the cylindrical ball 1 and projects further forward than the first conical ball 2. With the second conical ball formed, the cylindrical ball 1, the first and second cylindrical balls 2 and 3 form a ball 4 of a required shape, and the ball 4 is concentric with the ball 4 and has a slight difference. A screw 7 composed of a rotating cylindrical screw 5 and a cylindrical screw 6 projecting from the distal end side of the cylindrical screw 5 is inserted, and the balls 4 and the screws 7 are attached to pulleys 9 and 10 via a gear unit 8. It is designed to rotate at high speed.

A washing pipe 19 and a liquid supply pipe 12 fitted in the washing pipe are inserted into the cylindrical screw 5 of the screw 7 from the side opposite to the driving side.

Then, the balls 4 and the screw 7 arranged concentrically rotate at a high speed with a slight difference, and at the time of this high speed rotation, the slurry passes from the liquid supply port 11 through the liquid supply pipe 12 and passes through the screw 7 The liquid is supplied to the liquid supply chamber 13 and further supplied from the liquid supply outlet 14 to the mother liquor pool 15 formed between the ball 4 and the cylindrical screw to receive a high centrifugal force.

As a result, the solid matter d having a higher specific gravity than the liquid is
It is pressed against the inner wall of and forms a ring-shaped liquid layer inside it.

The separated solid d is conveyed to the tip of the first conical ball 2 by the screw 7, and the mother liquor is shaken off in the liquid removal zone 17 on the inner diameter side of the liquid level e regulated by the weir plate 16 to separate and drain the liquid. To be done.

On the other hand, the separated mother liquor overflows from the dam plate 16 and is discharged to the outside of the machine.

The cleaning liquid for cleaning the solids d is supplied from the cleaning port 18 to the cleaning liquid chamber 20 of the screw 7 through the cleaning pipe 19, and one or more cleaning liquid discharge holes 21 are provided to the base end of the second conical ball 3. By forming the inner diameter of the portion larger than the inner diameter of the tip portion of the first conical ball 2 and the inner diameter of the tip portion of the second conical ball 3 smaller than the inner diameter of the tip portion of the first conical ball 2, It is supplied to the cleaning pool 22 formed by the inner peripheral surface of the conical ball 3 and the end surface of the tip of the first conical ball 2.

The solid matter d separated and deliquored in the deliquoring zone 17 flows into the washing pool 22 occupied by the washing liquid and is immersed in the washing liquid,
The mother liquor adhering to the surface of the solid particles is diluted and washed together with the stirring action of the screw 7 during the transportation of the solid material.

Subsequently, the solid matter d is conveyed to the tip side of the second conical ball 3 by the screw 7, and the washing liquid is shaken off in the washing and dewatering zone 23 on the inner diameter side of the liquid level f regulated by the tip of the first conical ball 2. The solid particles are discharged from the solid cone discharge port 24 of the second conical ball 3 to the outside of the machine.

On the other hand, the separated cleaning liquid passes through the dewatering zone 17 and overflows into the mother liquor pool 15, so that the cleaning liquid comes into contact with the solid matter conveyed by the screw 7 to preliminarily wash the solid matter.

FIG. 2 is an explanatory view showing the principle of washing solids in a continuous centrifuge.

Next, the effect of washing the solid matter between the pool type continuous centrifuge of the present invention and the conventional type (a method in which the washing liquid is directly sprinkled onto the solid matter from the washing liquid discharge hole to wash the solid matter) The comparison is shown in Table 1.

As treatment conditions, the treated material was supplied to each continuous centrifuge in a resin bead slurry 760 l / Hr having a solid concentration of 50% by weight, and pure water was supplied at 280 l / Hr as a solid washing liquid.

As is clear from Table 1, the pool-type continuous centrifuge of the present invention is several times superior to the conventional type in the washing effect of solids, and as a merit, the product purity of solids is increased. The cleaning liquid tank becomes unnecessary, and corrosion due to chlorine ions is greatly suppressed particularly in the drying process of solids, so that the economical effect is remarkably improved.

〔The invention's effect〕

According to the present invention, the solid matter separated from the mother liquor in the first conical ball can be washed in the cleaning pool of the second conical ball 3, and further the cleaning liquid supplied to the cleaning pool can be transferred to the first conical ball side. Overflow and solids can be preliminarily washed in the mother liquor pool. Therefore, there are advantages that the cleaning effect of the solid matter is excellent, the product purity of the solid matter can be improved, the cleaning liquid tank becomes unnecessary, and the facility cost can be reduced.

[Brief description of drawings]

FIG. 1 is an overall sectional view of an essential part showing an embodiment of the present invention, FIG.
The figure is an enlarged cross-sectional view of the pool type solid matter cleaning unit of FIG. 1 is a cylindrical ball, 2 is a first conical ball, 3 is a second cylindrical ball, 4 is a ball, 7 is a screw, 15 is a mother liquor pool,
16 is a barrier plate, 22 is a washing pool, d is a solid matter, e is a liquid surface, f
Is the liquid level.

Claims (1)

[Claims] A first conical ball (2) for separating a mother liquor from a solid in a continuous centrifuge having a cleaning liquid supply mechanism for washing a solid, which has a ball and a screw, and a solid. And a second conical ball (3) for cleaning the second conical ball (3), the inner diameter of the base end of the second conical ball (3) is formed larger than the inner diameter of the tip of the first conical ball (2), and The inner diameter of the tip of the two conical balls (3) is made smaller than the inner diameter of the tip of the first conical balls (2) so that the inner peripheral surface of the second conical balls (3) and the first conical balls (2) are A cleaning pool (22) is formed with the end face of the tip,
A continuous centrifuge characterized in that the washing liquid supplied to the washing pool (22) is allowed to flow toward the first conical ball (2) side and is discharged together with the mother liquor.