JPH04171294A - Rotary pump for sludge - Google Patents

Abstract

PURPOSE:To restrain an advance of erosion of the mated part of divided type casings by providing a groove in the surface of a liner which is disposed in one casing, providing a protruding part in the surface of a liner which is disposed in the other casing, and providing a prescribed clearance between the groove and the protruding part. CONSTITUTION:A concentric groove 6a which surrounds a pump chamber 1a with the center in the diametrical direction of an inner casing 6 disposed at one divided type casing C2 centered is provided around the outer end surface of the inner casing 6, a protruding part 4a which is concentric and fitted in the concentric groove 6a is provided in a surface, facing the concentric groove 6a, of a liner disc 4 disposed at the other divided type casing C1, and a prescribed clearance (t) is provided between the concentric groove 6a and the protruding part 4a. The prescribed clearance (t) between the concentric groove 6a of the inner casing 6 and the protruding part 4a of the liner disc 4 is wave- shaped, so that the distance which reaches the mated part between the divided type casing C1 and C2 becomes long. Therefore, the swirl flow force of sludge is decreased, and it is thus possible to restrain erosion of the mated part largely.

Description

[Detailed description of the invention] [Industrial application field]

The present invention particularly relates to a sludge rotary pump used for discharging sludge produced in a coal liquefaction facility that produces liquid fuel from coal such as bituminous coal or lignite.

[Conventional technology]

As is well known, there are coal liquefaction facilities that liquefy coal, such as bituminous coal and lignite, to produce liquid fuel. Such coal liquefaction equipment is equipped with various reaction towers, synthesis towers, distillation towers, etc., and these are equipped with a slurry made of a mixture of coal pulverized to a predetermined particle size, a solvent, and a catalyst, or a plunger-type slurry supply pump. It is now powered by. By the way, sludge containing ash is generated in the liquid fuel generation process within these facilities, and the generated sludge is discharged outside the facility system.When discharging the sludge, a rotary pump for sludge having the following configuration is used. is used. As shown in FIG. 2 of its configuration explanatory diagram, this rotary pump for sludge has a pump casing 1 constructed by combining two split casings C1 and 02 via a ring-shaped seal 2, and The impeller 5 is installed inside the pump chamber 1a. More specifically, one of the upper split casings C1 shown in the figure is provided with a rotating shaft insertion hole, and the surface opposite to the lower split casing C2 is provided with the rotating shaft insertion hole. A disc-shaped liner disk 4 made of tungsten carbide (hereinafter referred to as WC) as a super hard member and having concentric through holes is removably fixed by mechanical means. A rotary shaft 3 is inserted into the rotary shaft insertion hole via a cylindrical spacer S, and the tip of the rotary shaft 3 passes through the through hole of the liner disk 4 and is formed inside the pump casing 1. Pump chamber 1a
The impeller 5 is fitted onto the tip of the rotary shaft 3. Furthermore, W is also applied to the surface opposite to the other split-type casing C1 on the upper side of the other split-type casing C2 on the lower side in the figure.
The inner casing 6 consisting of WC is removably fixed by mechanical means, and the inner wall of the pump chamber 1a is WC.
protected. In other words, by configuring the pump chamber 1a in this manner, it is possible to prevent corrosion of the inner wall of the pump chamber 1a due to erosion caused by the swirling flow of sludge. By the way, liner disk 4 and inner casing 6
A predetermined gap t is provided between the opposing surfaces near the outer ends of the impeller 5, that is, between the opposing surfaces at a position away from the impeller 5. Of course, it is preferable that such a gap t be 0. However, since it is necessary to absorb the thermal expansion between the two split casings C3 and C2, the gap t can only be set to O.
It is designed to ensure a slight gap t. Of the two split casings C1 and C2, what protrudes from the lower split casing C2 is the sludge suction lower and discharge port 8.

[Invention or problem to be solved]

As described above, since it is necessary to provide a predetermined gap between the opposing surfaces near the outer ends of the liner disk and the inner casing, there are problems to be solved as described below. In other words, when the rotating shaft is rotated and the impeller is rotated, sludge is sucked in from the suction port, the sucked sludge becomes a swirling flow, and is discharged from the discharge port with the force of the swirling flow. As it rotates, it passes through the gap and reaches the joint between the two split casings, and the area around this joint is severely eroded by erosion. When erosion progresses, these two split casings must be replaced. For example, in the case of sludge produced in coal liquefaction equipment, two separate casings must be replaced every 300 hours, which not only increases maintenance costs but also hinders continuous operation of the equipment. It became. Of course, increasing the outer diameter of the liner disk and increasing the distance between the opposing surfaces of these disks would reduce the force of the swirling flow of sludge and would be effective in preventing erosion, but this does not mean that the liner This is economically unfavorable because equipment costs increase due to the larger diameter of the disk and larger casing. Therefore, an object of the present invention is to provide a rotary pump for sludge that can suppress the progress of erosion due to erosion by reducing the force of the swirling flow of sludge that enters the joining portion of two split casings.

[Means to solve the problem]

The present invention has solved the above problems by focusing on the fact that erosion occurs based on the swirling flow of sludge. Therefore, the configuration of the rotary pump for sludge according to the present invention is as follows:
A split casing with a liner made of a super hard material on opposing sides is combined with a seal near the outer periphery of the liner, and a drive shaft inserted into the casing is inserted into the pump chamber of the casing. In a rotary pump for sludge, which has a rotating impeller installed therein, a liner (of one line) surrounding the pump chamber is provided on a surface near the outer periphery of a liner disposed in one of the split casings. A groove is provided, a protruding strip that engages with the groove is provided on the surface of the liner disposed on the other split type casing, and a predetermined gap is provided between these grooves and the protruding strip. .

[Effect]

According to the rotary pump for sludge according to the present invention, the predetermined gap or wave shape between the liner groove and the protruding strip is formed, so there is no need to increase the size of the liner or casing, and instead of the conventional flat gap. In this case, the distance between the two split casings can be made longer than in the case where the two split casings meet.

【Example】

An embodiment of the rotary pump for sludge according to the present invention will be described below with reference to FIG. 1, which is an explanatory diagram of the main part configuration, using the same reference numerals to denote the same parts and parts having the same functions as the conventional pump. That is, the reference numeral 1 shown in the figure is a pump casing,
This pump casing 1 is divided into two divided casings C1
and 02 are combined through a ring-shaped seal 2. One of the upper split-type casings C2 shown in the figure is provided with a rotary shaft insertion hole, and the surface facing the other lower split-type casing C2 is provided with a rotary shaft insertion hole that is concentric with the rotary shaft insertion hole. A liner disk 4 made of WC as an ultra-hard member having a through hole is removably fixed by mechanical means. Further, a rotating shaft 3 is inserted into this rotating shaft insertion hole via a cylindrical spacer S, and the tip of this rotating shaft 3 passes through the through hole of the liner disk 4 and is inserted into the pump casing l.
The impeller 5 is fitted onto the tip of the rotating shaft 3. Further, an inner casing 6 made of WC is removably fixed to the surface of the other split casing C2 on the lower side facing the one split casing C6 on the upper side, and is attached to the inner wall of the pump chamber 1a. is protected by WC. In other words, the above configuration is exactly the same as the conventional one. A predetermined gap t is provided between the opposing surfaces near the outer ends of the liner disk 4 and the inner casing 6, and between the opposing surfaces at a position away from the impeller 5. It is being That is, a concentric groove 6a is provided in the surface near the outer edge of the inner casing 6 disposed in one of the lower split-type casings C2, and is shaped to surround the pump chamber 1a around the radial center of the casing 6. The concentric groove 6a of the liner disk 4 disposed in the other upper split type casing C1
A concentric protruding strip 4a that engages with the concentric groove 6a is provided on a surface corresponding to the concentric groove 6a, and
The configuration is such that a predetermined gap t of 0.8 mm is provided between the two. Although not shown, both the casings C1 and C
Of course, the lower split type casing C2 is provided with a sludge suction lower and a discharge port 8, as in the conventional case. Hereinafter, the working mode of the rotary pump for sludge having the above-mentioned structure will be explained. As in the case of the conventional rotary pump for sludge, when the rotary shaft 3 is rotated and the impeller 5 is rotated, Sludge is sucked in from the suction lower, and the sucked sludge is pumped into the pump chamber la.
The sludge becomes a swirling flow inside, and is discharged from the discharge port 8 with the force of the swirling flow.The swirling flow of the sludge also passes through the gap t and reaches the joining part of the two divided casings C1 and 02. However, since the predetermined gap t between the concentric groove 6a of the inner casing 6 and the protruding strip 4a of the liner disk 4 is wave-shaped, the liner disk 4 and the inner casing 6 and the pump casings C1 and 02 have to be made larger. Needless to say, the distance to the joint between the two split casings C1 and C2 is longer than in the case of a conventional flat gap, and as a result, the momentum of the swirling flow of sludge is reduced here. Erosion caused by erosion in the area will be significantly suppressed. By the way, in the case of a conventional sludge rotary pump, 300
Although both casings C1 and 02 had to be replaced every hour or so, the rotary pump for sludge according to the embodiment of the present invention was disassembled and inspected after 511 hours had elapsed. No erosion was observed in the trench. However, even if there is no erosion in the concentric grooves of the liner disk 4 and the inner casing 6, erosion due to the machining protrusions has progressed in other parts, making it unusable, so the service life is only 500 years.
It is considered appropriate to set it to about an hour. In this way, the swirling flow of sludge can be reduced without increasing the size of the liner disk 4, inner casing 6, pump casing C, and 02, so that the rotational flow of casings CI and 02 due to erosion caused by the swirling flow of sludge can be reduced. It was confirmed that erosion of the joints can be effectively suppressed and that it has a significant effect on greatly improving the operating rate of coal liquefaction equipment. In the above, the liner disk 4 and the inner casing 6
Although we have explained an example in which WC is used as the material, the material is not limited to WC, for example, it is also possible to use ceramics, etc., and other sludge materials, which are limited to applications related to coal liquefaction equipment, can also be used. It is easily understood that the present invention can also be applied to rotary supply/discharge pumps such as the above.

【Effect of the invention】

As detailed above, according to the rotary pump for sludge according to the present invention, when the rotating shaft is rotated and the impeller is rotated, sludge is sucked in from the suction port, and the sucked sludge becomes a swirling flow. The force of the flow is discharged from the discharge port, and due to the swirling flow of this sludge, it passes through the gap and reaches the joint of the two split casings.
Since the predetermined gap between the liner groove and the protruding strip is wave-shaped, there is no need to increase the size of the liner or casing.
Compared to the case of a conventional flat gap, since the distance to the joint between the two split casings is longer, the swirling flow is weakened by the long gap, and as a result, erosion due to erosion near this joint can be suppressed. The time interval between replacements of the two split casings has been extended, and an extremely large effect can be expected on the continuous operation of the equipment due to the extension of the replacement time of the sludge rotary pump.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the main part configuration of a rotary pump for sludge according to an embodiment of the present invention, and FIG. 2 is an explanatory diagram of the configuration of a conventional rotary pump for sludge. 1... pump casing, la... pump chamber, 2...
...Ring-shaped seal, 3...Rotating shaft, 4...Liner disk, 4a...Protruding strip, 5...Impeller, 6
... Inner casing, 6a... Concentric groove, 7...
・Suction port, 8...Discharge port, C1, C2...Split type casing, h...Rotary shaft insertion hole, S...Spacer,
t...Gap between the joining part of the liner disk and the inner casing Patent applicant: Japan Lignite Liquefaction Co., Ltd. Representative Patent attorney: Akira Kanemaru −

Claims (1)

[Claims] 1. A pump chamber of a casing in which a split casing with a liner made of a super hard material arranged on opposing sides is combined with a seal near the outer periphery of the liner,
A rotary pump for sludge that includes an impeller that is rotated by a drive shaft inserted into the casing,
Among the split casings, at least one groove surrounding the pump chamber is provided on the surface near the outer periphery of the liner disposed on one of the split casings, and the liner disposed on the other split casing is provided with at least one groove surrounding the pump chamber. A rotary pump for sludge, characterized in that protruding strips that engage with the grooves are provided, and a predetermined gap is provided between these grooves and the protruding strips.