JP2019022871A - Autoclave - Google Patents

Abstract

To achieve a long periodic repair period and repair cost reduction of an autoclave and stable leaching reaction in the autoclave.SOLUTION: An autoclave A includes a vertical agitator 4, an air blow pipe 5, and a protector P attached to a horizontal air pipe 5b located below agitator impellers 4b. The protector P is equipped with a protection plate 10 attached to the upper half part of the horizontal air pipe 5b. The protection plate 10 is fixed to the horizontal air pipe 5b by a bolt 11 that vertically penetrates the horizontal air pipe 5b and is screwed by a nut 12. Because the protection plate 10 is so small as to be attached to only upper half part of the horizontal air pipe 5b, it does not disturb slurry flow and air dispersion and thus slurry is well agitated. Because the slurry does not contact the bottom edge of the bolt 11 so much, the nut is prevented from falling caused by vibration and abrasion.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an autoclave. More particularly, the present invention relates to an autoclave used for stirring a slurry containing a metal-containing solid and leaching a metal component with blown air.

  As a conventional technique of an autoclave for leaching metal in a raw material under high temperature and high pressure, there is Patent Document 1. In the autoclave according to Patent Document 1, a cylindrical can body is partitioned into a plurality of compartments, a vertical stirrer is disposed in each compartment, and a blow-in air pipe for injecting air or the like is provided below the stirrer. It is arranged. With this configuration, by stirring the slurry charged by the stirring blades of each stirrer and bringing it into contact with air or the like, the metal-containing solid is oxidized and the metal in the raw material can be leached.

  Autoclaves are also used for leaching nickel and cobalt from mixed sulfides of nickel and cobalt (hereinafter referred to as MS), and air is blown into MS slurry at high temperature and high pressure. A mixed aqueous solution of nickel sulfate and cobalt sulfate is produced by reacting oxygen with MS.

  By the way, in order to increase the reactivity and increase the leaching rate, a method of blowing air or the like is used from the lower side of the stirrer, and therefore, the MS slurry collides with the blown air tube under the stirrer, so that wear becomes intense. . And as wear progresses, holes are opened in the blown air pipe and air dispersion becomes worse, so that it is necessary to take measures against wear in the blown air pipe installed below the stirrer.

  Conventionally, a protector as shown in FIG. 4 has been installed as a countermeasure against wear of the blown air pipe. The protector 100 is provided with a pair of upper and lower protective plate halves 101, 101 each having a cylindrical shape divided in half in a horizontal air pipe 5b in a blown air pipe 5 located below a stirring blade 4b of a stirrer 4. The flanges 102, 102 formed on the protective plate halves 101, 101 are combined and coupled with bolts and nuts 103.

  However, in the protector 100 according to the prior art, the bolts and nuts 103 may be loosened easily due to vibration accompanying the flow of the slurry, or the bolts and nuts 103 may be detached due to wear caused by contact with the slurry. When a plurality of bolts and nuts 103 come off, the protective plate half 101 may come off. If this happens, the wear of the blown air pipe 5 is accelerated, so that the holes are opened in the horizontal air pipe 5b and the air dispersion becomes worse, so that the leaching reaction efficiency is lowered. In addition, the autoclave is periodically repaired to repair the horizontal air pipe 5b. Becomes shorter. Further, when the detached protective plate half 101 collides with the stirring blade 4b and the blown air pipe 5 and breaks the stirring blade 4b and the blown air pipe 5, there is a disadvantage that sudden repair is required.

In addition to the above, since the flange portion 102 of the protector 100 has a form protruding outward from the lateral air tube 5b of the blowing air tube 5, it has an adverse effect on slurry flow and air dispersion, and stable leaching reaction. There was sometimes inhibition.
Furthermore, since the protector 100 of the prior art has a structure with many bolts and nuts, it takes time and labor for the replacement work.

Special table 2009-530077 gazette

  In view of the above circumstances, the present invention provides an autoclave that can increase the periodic repair period of the autoclave, reduce the number of sudden repairs, enable a stable leaching reaction in the autoclave, and easily replace the protector. The purpose is to provide.

An autoclave according to a first aspect of the present invention includes a vertical stirrer having an air dispersion and slurry stirring agitator disposed inside an autoclave, a horizontal air pipe installed below the agitation blade, and the transverse air pipe. And a protector attached to the horizontal air pipe located below the stirring blade, the protector comprising an upper half of the horizontal air pipe. It is characterized by comprising a protective plate attached to.
The autoclave according to a second aspect of the present invention is the autoclave according to the first aspect, wherein the protective plate has a substantially semicircular cross section and has a length that covers the horizontal air pipe and a radius of curvature that closely contacts the outer periphery of the upper half of the horizontal air pipe. It is characterized by that.
The autoclave according to a third aspect of the present invention is the autoclave according to the second aspect, wherein the protection plate is coupled to the horizontal air pipe with a coupling bolt and a nut, and the coupling bolt penetrates the horizontal air pipe in the longitudinal direction, It is characterized by being screwed with a nut.
The autoclave according to a fourth aspect of the invention is characterized in that, in the third aspect of the invention, a protective pipe that passes through the inside of the horizontal air pipe and passes the shaft portion of the coupling bolt is vertically attached.
The autoclave according to a fifth aspect of the present invention is the autoclave according to the fourth aspect, wherein the protective pipe includes a pressure relief hole formed in a portion protruding from the lateral air pipe.

According to the first invention, the protective plate constituting the protector may be small enough to be attached to the upper half portion of the horizontal air pipe, so that good slurry agitation can be performed without adversely affecting the flow and air dispersion of the slurry. . For this reason, a stable leaching reaction is possible. Further, since the upper half of the horizontal air pipe is likely to be worn, if the portion is covered with a protective plate, it is possible to prevent holes due to wear of the horizontal air pipe.
According to the second invention, since the protective plate has a substantially semicircular arc shape and the radius of curvature is in close contact with the outer periphery of the upper half of the horizontal air pipe, there is no gap between the protector and the horizontal air pipe. The projected area is also reduced. For this reason, since the slurry flows smoothly along the outer peripheral surface of the protector, the slurry does not adversely affect the flow of the slurry and vibrations are hardly generated, so that loosening due to vibrations does not occur.
According to the third aspect of the invention, since the coupling bolt penetrates the horizontal air pipe, it does not protrude greatly to the outside of the horizontal air pipe, and good slurry agitation can be performed without hindering the flow of slurry and air dispersion. Further, since the slurry does not contact the lower end of the coupling bolt so much, it is possible to prevent the nut from loosening due to vibration or the like.
According to the fourth invention, since the inside of the horizontal air pipe is partitioned from the outside by the protective pipe, the slurry does not enter the inside of the horizontal air pipe. Further, the blown air does not leak from the gap.
According to the fifth invention, even if slurry or air is trapped in the protective pipe, it leaks out from the pressure release hole. Therefore, even if the nut fixing the coupling bolt is removed at the time of repair, the slurry or the like is ejected at a high pressure. Absent.

It is explanatory drawing of the protector part in the autoclave of this invention. (A) The figure is the elements on larger scale of the protector shown in FIG. 1, (B) The figure is sectional drawing of (A) figure. It is schematic structure explanatory drawing of an autoclave. It is explanatory drawing of the conventional protector 100, Comprising: (A) A figure is a whole explanatory drawing, (B) A figure is a longitudinal cross-sectional view.

(Schematic configuration of autoclave)
First, a schematic configuration of the autoclave A will be described based on FIG.
The autoclave A has a cylindrical horizontally long can 1. The can 1 has a plurality (5 in the figure) of compartments 2, and the adjacent compartments 2 are partitioned by a partition wall 3. Yes.
Each compartment 2 is provided with a vertical stirrer 4 for air dispersion and slurry stirring and a blown air pipe 5 for injecting air or the like.

  The vertical stirrer 4 includes a stirring shaft 4a and a stirring blade 4b inserted into a can body. Although the drive part is provided above the can body 1, illustration is abbreviate | omitted. The blow-in air pipe 5 includes a vertical air pipe 5a and a horizontal air pipe 5b attached to the lower end of the vertical air pipe 5a. Although the upper end of the blowing air pipe 5 is connected to an air source, these illustrations are omitted.

  The horizontal air pipe 5b in the blowing air pipe 5 is located below the stirring blade 4b. Moreover, the front-end | tip of the horizontal air pipe 5b, ie, the air outlet 5c, is located below the center position of the said stirring blade 4b. The reason why the air outlet 5c is opened downward is to prevent the flowing slurry from entering the blowing air pipe 5.

  The material of the blown air pipe 5 according to the above configuration is selected with emphasis on corrosion resistance. For example, SUS316L, which is titanium or austenitic stainless steel, is preferable because the cost is low and the workability is not problematic. It is also possible to use a wear-resistant steel pipe coated with a high chromium-based cobalt alloy material or ceramics.

(Configuration of protector P)
Next, the protector P will be described with reference to FIGS.
The horizontal air pipe 5b of the blow-in air pipe 5 is easily worn because the slurry stirred by the stirring blade 4b comes into contact with the fluid at a high flow rate, and this part is sometimes referred to as a protection required part in this specification.
It is the protector P that protects the protection required portion from wear, and the protector P includes the protection plate 10 and the coupling bolt 11 as main components.

  The protection plate 10 is attached to the upper half portion of the horizontal air pipe 5b as a protection required portion. The shape of the protective plate 10 has a substantially semicircular cross section. The meaning of “substantially semicircular arc shape” in the present specification is not an arc shape extending 180 ° in a strict sense, but means that it is sufficient to cover substantially the upper half of the horizontal air pipe 5b. Therefore, an arc shape with an angle smaller than 180 ° and an arc shape with an angle larger than 180 ° are included in the concept of “semi-arc shape” in this specification.

  The protection plate 10 has a radius of curvature that is in close contact with the outer periphery of the upper half portion of the horizontal air pipe 5b. That is, it is a round tile-shaped member that is in close contact with the upper surface of the horizontal air pipe 5b.

  With such a shape, when the protection plate 10 is attached to the horizontal air pipe 5b, no gap is formed between the protection plate 10 and the horizontal air pipe 5b, and the projected area of the protector P is reduced. In other words, the member has a small size.

The material of the protection plate 10 may be selected from the viewpoint that the cost for wear and replacement is low, or may be selected from the viewpoint of a material that does not easily wear.
Inexpensive materials include metals such as SUS steel, which is stainless steel, and SS steel, which is a general rolled steel, and the protective plate 10 manufactured using these materials has low production costs and can reduce repair costs.

  In the case where the protection plate 10 is provided with wear resistance, the protection plate 10 itself may be made of a wear-resistant alloy or ceramics, or an inexpensive base metal may be coated with a wear-resistant alloy or ceramics. Good. Examples of wear-resistant alloys suitable for coating include, but are not limited to, alloys (trade name “Stellite”) in which chromium, tungsten, or the like is contained in cobalt as a main component.

  The thickness of the protective plate 10 is arbitrary, and may be selected from the clearance with the stirring blade 4b and the availability of materials. In many cases, about 10 to 15 mm is preferable, and about 11 to 13 mm is particularly preferable. If the availability is high, the repair cost can be reduced.

The length of the protection plate 10 may be the entire length of the horizontal air pipe 5b, or a portion that is particularly susceptible to wear may be selected to cover the portion.
In the embodiment shown in FIG. 1, the protection plate 10 covers almost the entire length of the horizontal air pipe 5b, but does not cover the upper surface portion of the air outlet 5c. However, it goes without saying that this portion may be covered.

  A connecting bolt 11 is connected to the protective plate 10. The connecting portion of the connecting bolt 11 is a central portion in the circumferential direction of the protection plate 10, and is a plurality of locations in the longitudinal direction of the protection plate 10. As a method of coupling, a male screw formed at the base of the coupling bolt 11 may be screwed into a screw hole formed in the protective plate 10, and the base of the coupling bolt 11 is inserted into a hole formed in the protective plate 10 and welded. May be.

  The coupling bolt 11 is coupled to the horizontal air pipe 5b. The coupling bolt 11 hangs downward from the protective plate 10, and a nut 12 can be screwed to the lower end thereof.

A protective pipe 21 through which the shaft portion of the coupling bolt 11 passes is vertically attached to the horizontal air pipe 5b. The protective pipe 21 may be attached to the horizontal air pipe 5b by any method such as making a hole in the tube wall of the horizontal air pipe 5b, inserting the protective pipe 21, and welding it.
In this case, if the mounting portion of the protective pipe 21 is sealed with a weld overlay, the protective pipe 21 can partition the inside of the horizontal air pipe 5b from the outside, so that the slurry is placed inside the horizontal air pipe 5b. There is no invasion. Further, the blown air does not leak from the gap.

  As for the coupling bolt 11, the axial part is inserted in the inside of the protection pipe 21, penetrates in the vertical direction, and protrudes downward. The protection pipe 21 is fastened from above and below by screwing the nut 12 to the tip of the coupling bolt 11 so that the protection plate 10 is fixed to the horizontal air pipe 5b.

A pressure relief hole 13 is formed in a portion of the protective pipe 21 that protrudes downward from the horizontal air pipe 5b.
Due to this pressure release hole 13, the air and slurry filled in the protective pipe 21 always leak out. For this reason, the situation where only the inside of the protection pipe 21 becomes high pressure when the pressure in the can 1 is released is avoided. Therefore, even if the coupling bolt 11 or the nut 12 is loosened when the protector P is replaced, there is no inconvenience that the internal air or slurry is suddenly ejected.

(Effect of protector P)
In the autoclave A of the present embodiment, the slurry flows most vigorously in the rotating region of the stirring blade 4b and its periphery. Therefore, the slurry is flowing greatly below the stirring blade 4b and around the horizontal air pipe 5b. And it is the outer peripheral surface of the upper half of the horizontal air pipe 5b that the slurry flows in contact with the horizontal air pipe 5b. When used in such a situation, the autoclave of the present embodiment has the following effects.

(1) Since the outer periphery of the region in the upper half of the horizontal air pipe 5b in which the slurry contacts and flows is covered with the protective plate 10, the wear of the horizontal air pipe 5b can be effectively prevented.

(2) Since the protection plate 10 has a round roof shape, the projected area is small and does not obstruct the flow of the slurry. Therefore, the slurry flows smoothly and a stable leaching reaction is possible.

(3) The lower end of the coupling bolt 11 for fixing the protective plate 10 protrudes below the horizontal air pipe 5b, and the nut 12 is also positioned below the horizontal air pipe 5b. This lower position is a place where the flow of the slurry is small, so that the lower end portions of the nut 12 and the bolt 11 are not easily worn. Therefore, the replacement frequency due to the wear of the bolt and nut is reduced, and an accident such as dropping of the protection plate 10 occurs Hard to occur.

(4) Since there is no flange or bolt in the horizontal position of the circular cross section in the horizontal air pipe 5b where the flow of the slurry is large, there is no wear of the flange or the bolt due to contact with the slurry, and the protector P A drop-out accident is unlikely to occur. In addition, since the flow of the slurry is not disturbed, the slurry flows smoothly and a stable leaching reaction is possible.

(Effect compared with conventional technology)
Since the effects (1) to (4) are exhibited, in this embodiment, the slurry is less likely to come into contact with the nut 12, and a particular inconvenience arises even after about one year of operation of the actual machine according to the illustrated embodiment. There wasn't.
On the other hand, when the conventional protector 100 shown in FIG. 4 is used, the bolts and nuts 103 are worn and the protective plate 101 is detached due to wear due to contact with the mixed sulfide slurry containing nickel and cobalt. There was an accident with a frequency of about once every three months that the horizontal air pipe 5b itself was perforated due to the removal of the protective plate 101. From this comparison, the accident prevention effect by the protector P of the present embodiment is remarkable.

  From the above, according to this embodiment, the periodic repair period of the autoclave A can be lengthened, the number of sudden repairs can be reduced, stable leaching reaction in the autoclave A is enabled, and the protector P can be replaced. Can be provided.

  The autoclave of the present invention is particularly useful for measures against wear of air blowing pipes in a high pressure reaction vessel of a mixed sulfide (MS) of nickel and cobalt, realizes easy replacement of the protector P, The influence on air dispersion can be minimized.

  The autoclave of the present invention is suitable for MS leaching as described above. However, the present invention is not limited to this application, and any autoclave can be used as long as the structure blows air or the like while stirring the slurry.

DESCRIPTION OF SYMBOLS 1 Can body 2 Compartment 3 Partition wall 4 Vertical stirrer 4b Stirring blade 5 Blowing air pipe 5b Horizontal air pipe 10 Protection plate 11 Coupling bolt 12 Nut 13 Pressure release hole 21 Protection pipe

Claims (5)

A vertical stirrer having a stirring blade for air dispersion and slurry stirring, disposed inside the autoclave;
A blown air pipe comprising a horizontal air pipe installed below the stirring blade and a vertical air pipe connected to the horizontal air pipe;
A protector attached to the transverse air pipe located below the stirring blade,
The protector comprises a protective plate attached to the upper half portion of the horizontal air pipe. 2. The protection plate according to claim 1, wherein the protection plate has a substantially semicircular cross section, and has a length that covers the horizontal air pipe and a radius of curvature that closely adheres to the outer periphery of the upper half of the horizontal air pipe. Autoclave. The protective plate is coupled to the horizontal air pipe with a coupling bolt and a nut,
The autoclave according to claim 2, wherein the connecting bolt penetrates the horizontal air pipe in the vertical direction and is screwed with the nut. The autoclave according to claim 3, wherein a protective pipe that passes through the inside of the horizontal air pipe and passes the shaft portion of the coupling bolt is vertically attached. 5. The autoclave according to claim 4, wherein the protective pipe includes a pressure release hole formed in a portion protruding from the horizontal air pipe.

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