JP6905211B2 - Autoclave - Google Patents

Description

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

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

An autoclave is also used for leaching nickel and cobalt from a mixed sulfide of nickel and cobalt (hereinafter referred to as MS). Air or the like is blown into the MS slurry in a high temperature and high pressure state, and the mixture is stirred by a stirring blade in the air. A mixed aqueous solution of nickel sulfate and cobalt sulfate is produced by reacting oxygen with MS.

By the way, a method of blowing air or the like from below the stirrer is used in order to increase the reactivity and the leaching rate, and therefore, the MS slurry collides with the blown air pipe under the stirrer, resulting in severe wear. .. Then, as the wear progresses, a hole is opened in the blown air pipe and the dispersion of air becomes poor. Therefore, it is necessary to take measures against wear on the blown air pipe installed below the stirrer.

Conventionally, a protector as shown in FIG. 4 has been installed as a measure against wear of the blown air pipe described above. In this protector 100, a pair of upper and lower protective plate halves 101 and 101 having a cylindrical shape divided in half are attached to the lateral air pipe 5b in the blown air pipe 5 located below the stirring blade 4b of the stirrer 4, and both of them. The flanges 102 and 102 formed on the protective plate semifields 101 and 101 are combined and joined by bolts and nuts 103.

However, in the protector 100 of the above-mentioned prior art, the bolts and nuts 103 may be easily loosened due to vibration accompanying the flow of the slurry, or the bolts and nuts 103 may come off due to wear caused by contact with the slurry. When the plurality of bolts and nuts 103 are removed, the protective plate half body 101 may be removed. In that case, the blown air pipe 5 is worn out faster, so that a hole is formed in the lateral air pipe 5b and the air dispersion is deteriorated, so that the leaching reaction efficiency is lowered, and the autoclave is regularly repaired for the repair of the lateral air pipe 5b. Becomes shorter. Further, if the detached protective plate half body 101 collides with the stirring blade 4b and the blowing air pipe 5 and damages the stirring blade 4b and the blowing air pipe 5, there is a problem that sudden repair is required.

In addition to the above, since the flange portion 102 of the protector 100 protrudes outward from the lateral air pipe 5b of the blown air pipe 5, it adversely affects the flow and air dispersion of the slurry and causes a stable leaching reaction. It sometimes hindered me.
Further, since the protector 100 of the above-mentioned conventional technique has a structure having many bolts and nuts, it takes time and effort to replace the protector 100.

Special Table 2009-530077 Gazette

In view of the above circumstances, the present invention provides an autoclave in which the periodic repair period of the autoclave can be extended, the number of sudden repairs can be reduced, a stable leaching reaction can be performed in the autoclave, and the protector can be easily replaced. The purpose is to provide.

The autoclave of the first invention includes a vertical stirrer having stirring blades for air dispersion and slurry stirring, which is arranged inside the autoclave, and a transverse air pipe and a transverse air pipe installed below the stirring blade. It is provided with a blown air pipe including a vertical air pipe connected to the above, and a protector attached to the horizontal air pipe located below the stirring blade, and the protector is an upper half portion of the horizontal air pipe. It is characterized by consisting of a protective plate attached to the air.
In the first invention, the autoclave of the second invention has a substantially semicircular cross section of the protective plate, has a length covering the lateral air pipe, and has a radius of curvature in close contact with the outer circumference of the upper half portion of the lateral air pipe. It is characterized by doing.
In the second invention, the autoclave of the third invention is such that the protective plate is connected to the lateral air pipe by a coupling bolt and a nut, and the coupling bolt penetrates the lateral air pipe in the longitudinal direction. It is characterized by being screwed with a nut.
In the third invention, the autoclave of the fourth invention is vertically attached with a protective pipe that penetrates the inside of the lateral air pipe and passes the shaft portion of the coupling bolt , and the protective pipe is attached to the lateral air pipe. The mounting portion is characterized in that it is hermetically sealed.
The autoclave of the fifth invention is characterized in that, in the fourth invention, the protective pipe is provided with a pressure relief hole formed in a portion protruding downward from the lateral air pipe.

According to the first invention, since the protective plate constituting the protector may have a small size that is only attached to the upper half of the horizontal air pipe, good slurry agitation can be performed without adversely affecting the flow and air dispersion of the slurry. .. Therefore, a stable leaching reaction is possible. Further, since it is the upper half of the lateral air pipe that is easily worn, if that portion is covered with a protective plate, it is possible to prevent holes due to wear of the lateral air pipe.
According to the second invention, since the protective plate has a substantially semicircular arc shape and the radius of curvature is such that the radius of curvature is in close contact with the outer circumference of the upper half of the lateral air pipe, there is no gap between the protector and the lateral air pipe, and the protector The projected area also becomes smaller. Therefore, since the slurry flows smoothly along the outer peripheral surface of the protector, the flow of the slurry is not adversely affected and vibration is unlikely to occur, so that loosening due to vibration does not occur.
According to the third invention, since the coupling bolt penetrates the transverse air pipe, it does not protrude significantly to the outside of the transverse air pipe, and good slurry agitation can be performed without hindering the flow and air dispersion of the slurry. Further, since the slurry does not come into contact with 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 cross air pipe is partitioned from the outside by the protective pipe, the slurry does not enter the inside of the cross air pipe. In addition, the blown air does not leak from the gap.
According to the fifth invention, even if the slurry or air is trapped in the protective pipe, it leaks from the pressure relief hole. Therefore, even if the nut fixing the coupling bolt is removed at the time of repair, the slurry or the like is not ejected at high pressure. do not have.

It is explanatory drawing of the protector part in the autoclave of this invention. (A) is a partially enlarged view of the protector shown in FIG. 1, and (B) is a cross-sectional view of FIG. 1 (A). It is a schematic block diagram of an autoclave. It is an explanatory view of the conventional protector 100, (A) is an overall explanatory view, and (B) is a vertical sectional view.

(Outline configuration of autoclave)
First, a schematic configuration of the autoclave A will be described with reference to FIG.
The autoclave A has a cylindrical horizontally long can body 1, the can body 1 has a plurality of (five in the figure) compartments 2, and the adjacent compartments 2 are partitioned by a partition wall 3. There is.
In each of the compartments 2, a vertical stirrer 4 for air dispersion and slurry agitation and a blow-in air pipe 5 for injecting air or the like are arranged.

In the vertical stirrer 4, a stirring shaft 4a and a stirring blade 4b inserted into the can body are shown. The drive unit is provided above the can body 1, but the illustration is omitted. The blown air pipe 5 includes a vertical air pipe 5a and a horizontal air pipe 5b laterally attached to the lower end thereof. The upper end of the blown air pipe 5 is connected to the air source, but these are not shown.

The lateral air pipe 5b in the blown air pipe 5 is located below the stirring blade 4b. Further, the tip of the cross air pipe 5b, that is, the air outlet 5c is located below the center position of the stirring blade 4b. The reason why the air outlet 5c is opened downward is to prevent the flowing slurry from entering the blown air pipe 5.

The material of the blown air pipe 5 according to the above configuration is selected with an emphasis on corrosion resistance. For example, titanium or SUS316L, which is an austenitic stainless steel, is preferable because the cost is low and there is no problem in workability. It is also possible to use a wear-resistant steel pipe coated with a high-chromium cobalt alloy material or ceramics.

(Structure of protector P)
Next, the protector P will be described with reference to FIGS. 1 and 2.
The lateral air pipe 5b of the blown air pipe 5 is easily worn because the slurry stirred by the stirring blade 4b comes into contact with each other at a high flow velocity, and this portion may be referred to as a protection required portion in the present specification.
It is the protector P that protects the protection-required portion from wear, and the protector P has a protective plate 10 and a coupling bolt 11 as main components.

The protective plate 10 is attached to the upper half of the lateral air pipe 5b as a protection-requiring portion. The shape of the protective plate 10 is a substantially semicircular arc shape in cross section. In the strict sense, the meaning of "substantially semi-circular shape" in the present specification is not an arc shape extending to 180 °, but generally means that it is sufficient to cover substantially the upper half of the lateral air pipe 5b. Therefore, both an arc shape having an angle smaller than 180 ° and an arc shape having an angle larger than 180 ° are included in the concept of "semi-circular shape" as used herein.

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

Due to such a shape, when the protective plate 10 is attached to the lateral air pipe 5b, no gap is formed between the protective plate 10 and the lateral air pipe 5b, and the projected area of the protector P is also reduced. In other words, it is a member with small dimensions.

The material of the protective plate 10 may be selected from the viewpoint of low cost for wear and replacement, or may be selected from the viewpoint of a material that is hard to wear.
As an inexpensive material, there are metals such as SUS steel which is stainless steel and SS steel which is a general rolled steel material, and the protective plate 10 manufactured by these has a low production cost and can reduce the repair cost.

When the protective plate 10 is to be provided with wear resistance, the protective 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 the wear-resistant alloy suitable for coating include, but are not limited to, an alloy in which cobalt, which is the main component, contains chromium, tungsten, or the like (trade name “Stellite”).

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

The length of the protective plate 10 may be the total length of the cross air pipe 5b, or a portion that is particularly susceptible to wear may be selected and set to cover that portion.
In the embodiment shown in FIG. 1, the protective plate 10 covers almost the entire length of the lateral 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 coupling bolt 11 is coupled to the protective plate 10. The connecting points of the connecting bolts 11 are the central portions in the circumferential direction of the protective plate 10, and are a plurality of connecting points in the longitudinal direction of the protective plate 10. As for the method of joining, the male screw formed at the base of the connecting bolt 11 may be screwed into the screw hole formed in the protective plate 10, and the base of the connecting bolt 11 is inserted into the hole formed in the protective plate 10 and welded. You may.

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

A protective pipe 21 through which the shaft portion of the coupling bolt 11 is passed is vertically attached to the lateral air pipe 5b. The protective pipe 21 may be attached to the lateral air pipe 5b by any method such as making a hole in the pipe wall of the lateral air pipe 5b, inserting the protective pipe 21, and fixing the welding.
In this case, if the mounting portion of the protective pipe 21 is sealed with a weld overlay or the like, the protective pipe 21 can partition the inside of the lateral air pipe 5b from the outside, so that the slurry is inside the lateral air pipe 5b. It does not invade. In addition, the blown air does not leak from the gap.

The shaft portion of the coupling bolt 11 is inserted into the protective pipe 21 to penetrate in the vertical direction and protrude downward. By screwing the nut 12 to the tip of the coupling bolt 11, the protective pipe 21 is tightened from above and below, and the protective plate 10 is fixed to the lateral air pipe 5b.

A pressure relief hole 13 is formed in a portion of the protection pipe 21 that protrudes downward from the lateral air pipe 5b.
Through the pressure release hole 13, the air or slurry filled in the protective pipe 21 always leaks out. Therefore, it is possible to avoid a situation in which only the inside of the protective pipe 21 becomes high pressure when the pressure inside the can body 1 is released. Therefore, even if the coupling bolt 11 or the nut 12 is loosened when the protector P is replaced, the inconvenience that the internal air or slurry is suddenly blown out is eliminated.

(Effect of protector P)
In the autoclave A of the present embodiment, the slurry flows most violently in and around the rotating region of the stirring blade 4b. Therefore, a large amount of slurry is flowing below the stirring blade 4b and around the cross air pipe 5b. Then, it is the outer peripheral surface of the upper half of the cross air pipe 5b that the slurry comes into contact with the cross air pipe 5b and flows. 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 lateral air pipe 5b where the slurry comes into contact and flows is covered with the protective plate 10, wear of the lateral air pipe 5b can be effectively prevented.

(2) Since the protective plate 10 has a round roof tile shape, the projected area is small and does not interfere with 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 projects below the lateral air pipe 5b, and the nut 12 is also located below the lateral air pipe 5b. Since this lower position is where the flow of slurry is small, wear of the lower ends of the nuts 12 and bolts 11 is unlikely to occur, so the frequency of replacement due to wear of the bolts and nuts is low, and accidents such as the protective plate 10 falling off may occur. It is unlikely to occur.

(4) Since there are no flanges or bolts in the lateral position of the circular cross section in the transverse air pipe 5b where the flow of the slurry is large, the flanges and bolts do not wear due to contact with the slurry, and the protector P does not wear. Dropout accidents are unlikely to occur. Further, since the flow of the slurry is not obstructed, the slurry flows smoothly and a stable leaching reaction is possible.

(Effect compared with conventional technology)
Since the above effects (1) to (4) are exhibited, the slurry rarely comes into contact with the nut 12 in this embodiment, and a particular inconvenience occurs 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 disengaged due to wear due to contact with the mixed sulfide slurry containing nickel and cobalt. An accident in which a hole was formed in the lateral air pipe 5b itself due to the protective plate 101 being removed occurred at a frequency of about once every three months. From this comparison, the accident prevention effect of the protector P of the present embodiment is remarkable.

From the above, according to the present embodiment, the periodic repair period of the autoclave A can be extended, the number of sudden repairs can be reduced, a stable leaching reaction can be performed in the autoclave A, and the protector P can be replaced. Can provide an easy autoclave A.

The autoclave of the present invention is particularly useful as a countermeasure against wear of the air blowing pipe in a high-pressure reaction vessel of a mixed sulfide (MS) of nickel and cobalt, realizes ease of replacement of the protector P, and allows the flow of the slurry and the flow of the slurry. The effect on air dispersion can be minimized.

The autoclave of the present invention is suitable for leaching MS as described above, but is not limited to this application, and can be used for any autoclave as long as it has a structure in which air or the like is blown while stirring the slurry.

1 Can body 2 Separation room 3 Partition wall 4 Vertical stirrer 4b Stirring blade 5 Blow-in air pipe 5b Horizontal air pipe 10 Protective plate 11 Coupling bolt 12 Nut 13 Depressurization hole 21 Protective pipe

Claims (5)

A vertical stirrer with agitating blades for air dispersion and slurry agitation, located inside the autoclave.
A blown air pipe composed of a horizontal air pipe installed below the stirring blade and a vertical air pipe connected to the horizontal air pipe.
It is equipped with a protector attached to the lateral air pipe located below the stirring blade.
The protector is an autoclave comprising a protective plate attached to the upper half portion of the transverse air pipe. The first aspect of the present invention, wherein the protective plate has a substantially semicircular cross section, has a length covering the cross air pipe, and has a radius of curvature that is in close contact with the outer periphery of the upper half portion of the cross air pipe. Autoclave. The protective plate is connected to the lateral air pipe by connecting bolts and nuts.
The autoclave according to claim 2, wherein the coupling bolt penetrates the transverse air pipe in the vertical direction and is screwed with the nut. A protective pipe that penetrates the inside of the lateral air pipe and passes the shaft portion of the coupling bolt is vertically attached , and the attachment portion of the protective pipe to the lateral air pipe is hermetically sealed. The autoclave according to claim 3. The autoclave according to claim 4, wherein the protective pipe is provided with a pressure relief hole formed in a portion protruding downward from the lateral air pipe.

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