JPH0726626B2 - Liquid ring pump device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a liquid ring vacuum pump (hereinafter, also simply referred to as “liquid ring pump”) device, particularly in a weightless environment such as a space station. More specifically, the present invention relates to a liquid ring pump effective for use, and more specifically, a mixed pressure increase of different gas or gas-liquid two-phase fluids (hereinafter, also referred to as mixed fluid or treatment fluid) having two or more different pressure ranges, The present invention relates to a liquid ring pump device suitable for gas-liquid separation.

[Conventional technology]

Conventionally, in general, a liquid ring pump may be used for the purpose of sucking and treating exhaust gas or a gas-liquid mixed fluid. The fluid discharged from the liquid ring pump is a mixed fluid containing gas (gas) and a part of the sealing liquid. For the purpose of separating the mixed fluid into gas and liquid and recovering the sealing liquid as the working liquid. A gas-liquid separation tank utilizing gravity may be provided on the downstream side of the liquid ring pump. Then, normally, a circulation pump for returning the separated liquid to the liquid ring pump is separately provided.

On the other hand, for the purpose of reducing the installation space, there is also known a technology in which a replenishment pump for supplying a working liquid (sealing liquid) of the liquid ring pump is integrated with the liquid ring pump body (for example, Japanese Utility Model Laid-Open No. 57-1).
42192).

[Problems to be Solved by the Invention]

However, in the former case of the conventional example, it is necessary to separately provide a gas-liquid separation tank and a circulation pump, and in the latter case, it is necessary to separately provide a gas-liquid separation tank. It becomes complicated and large / weight, and the installation space must be large.

Therefore, the space and weight of the space station are limited, and the space station is not suitable for use in a weightless place.

Further, in the above-mentioned conventional example, for two or more kinds of fluids having different pressure regions, separate liquid ring pump devices must be installed according to the respective fluid pressure regions, which makes the entire device complicated and large. It was unavoidable, and from this point too, it was not suitable for use as a space station.

Further, there is known a conventional example in which the same fluid is pressurized by a multi-stage liquid ring pump (for example, JP-A-60-132090 and JP-A-62-1830).
However, they are the same (same pressure and same pressure).
It's just for fluids.

Therefore, the present invention provides a liquid ring pump device that simplifies and downsizes the conventional device, is particularly suitable for use in a zero-gravity environment, and is suitable for processing gas-liquid two-phase fluids having different pressure ranges. The purpose is to provide.

[Means for Solving the Problems]

In order to achieve the above object, the liquid ring pump device according to the present invention,
A multi-stage compression type liquid ring pump unit having a plurality of impellers and a Pitot pump unit are directly connected to each other by the same drive shaft, and the liquid ring pump has a fluid inlet at the first stage compression stage as well as an arbitrary stage after the second stage compression stage. The intermediate compression stage is also provided with a fluid inlet capable of sucking a fluid from the outside, and further connects the fluid discharge port of the final compression stage and the fluid inlet of the pitot pump part, and the inside of the casing of the pitot pump part. A rotary drum mounted on the drive shaft is provided, an opening for inflowing a gas-liquid mixed fluid, an exhaust port for separated gas, and a liquid reservoir on the circumferential surface of the rotary drum are formed on the rotary drum wall. An impeller is provided in the drum so that the inflowing fluid is directed outward in the radial direction of the rotating drum, and an opening of a pitot tube is arranged in the liquid reservoir.
The outlet side of the pitot tube is connected to the first compression stage side of the liquid ring pump section via a cooling means.

[Action]

In the above configuration, one gas or gas-liquid mixed fluid having a certain fluid pressure is sucked from the suction port of the liquid seal pump of the previous stage (first stage), is compressed and pressure-enhanced by the liquid seal pump, and then is different in other pressure regions. When there is a suction port for gas or gas-liquid mixed fluid, it merges with the fluid and is sucked by the liquid ring pump of the subsequent stage (if there are several stages, this corresponds to the intermediate stage). And
In this case as well, after the pressure was increased by compression (if there is a liquid ring pump in the subsequent stage, and if there is a suction port for another mixed fluid with a different pressure range, it is sucked together with the fluid) and then placed in the final stage. It is discharged to the pitot pump part, where the mixed fluid is repelled by the centrifugal gas-liquid separation impeller in the pitot pump part to the radial outside of the rotating drum, the mixed fluid is separated into gas and liquid, and the gas is discharged from the exhaust port. On the other hand, while the separated liquid is discharged to the outside, the separated liquid is returned to the liquid sealing pump unit through the Pitot tube while being held in the liquid storage unit by the centrifugal force of the rotating drum, and then refluxed.

〔Example〕

An embodiment of the present invention will be described below with reference to the accompanying drawings.

The figure shows a conceptual diagram of the whole liquid ring pump device according to the present invention,
Its main configuration is a gas or gas-liquid two-phase fluid (hereinafter referred to as a processing fluid or mixed fluid) with different pressure ranges.
A two-stage liquid ring pump unit W having two fluid suction pipes (ports) 5 and 8, a pitot pump unit P having a centrifugal gas-liquid separation function directly connected to the same by a same drive shaft 10, an electric motor M for driving these, It is a cooler (means) 24.

Although the illustrated embodiment is a two-stage liquid ring pump for convenience of description, it may be a multi-stage liquid pump in which the number of stages W1 to Wn corresponding to the number n of processing fluids (number of pressure regions) is increased. In any case, the pitot pump part P is connected to the liquid ring pump Wn at the last stage.

The liquid ring pumps W1 and W2 themselves in this figure are conventionally known. That is, a circular casing 1 (11) and an impeller 2 (12) form a main body, and the impeller 2 (12) is attached at a position eccentric to the casing 1 (11). When a proper amount of the sealing liquid 3 (13) is put in the casing 1 (11) and the impeller 2 (12) is rotated, the liquid forms a circular liquid film concentric with the casing 1 (11) by centrifugal force. Exercise while doing. As a result, a space closed by the blade and the blade adjacent to the liquid film is generated, and the volume of this space changes as the impeller 2 (12) rotates, and suction, compression, and exhaust are continuously performed. In the process of this action, the suction fluid is compressed and discharged together with a part of the sealing liquid 3 (13) from the discharge port 9 (15).
As the sealing liquid 3 (13), water is usually used in many cases, but other liquid may be used.

As shown in the figure, the liquid ring pump section W is composed of a first stage (front stage) liquid ring pump W1 and a second stage (rear stage) liquid ring pump W2 directly connected to the same by a same drive shaft. ing.
A pitot pump section P having a centrifugal gas-liquid separation function is directly connected to the liquid ring pump W2 at the latter stage by the same drive shaft 10. Therefore, the liquid ring pumps W1 and W2 and the pitot pump unit P are all directly connected to the same drive shaft 10 driven by the electric motor M. In addition, B is a bearing and a seal member.

A first fluid suction port 4 is provided on the front wall of the casing 1 of the liquid seal pump W1 at the preceding stage, and a first suction pipe 5 is connected to this. And the discharge port 9 of the liquid pump of the previous stage
Is connected to the suction port 14 of the second-stage liquid ring pump via a communication passage 6, and a second suction pipe 8 for sucking a second fluid is connected to the communication passage 6.

The discharge port 15 of the latter-stage liquid ring pump is connected to a fluid inlet 17A provided in a casing 17 of the Pitot pump section via a communication passage 16.

Inside the casing 17 of the pitot pump part P, a rotary drum 18 mounted on the drive shaft 10 is provided. Of the wall surfaces of this rotary drum 18, the front wall 18A on the fluid inlet side
Is provided with an opening 20 for receiving a fluid, and an exhaust port 21 for separating gas is provided on a rear wall surface 18C at a position opposed to the opening 20. However, the exhaust port 21 does not necessarily have to be provided in the rear wall 18C, and may be connected to an exhaust pipe 27 described later by an appropriate pipe. Further, a liquid reservoir 26 for holding the separated liquid is formed on the circumferential wall surface 18B of the rotary drum 18. The gas discharged from the exhaust port 21 is exhausted to the outside through an exhaust pipe 27 provided on the rear wall of the casing 17 of the pitot pump portion P.

Inside the rotary drum 18, an impeller 19 is mounted on the drive shaft 10, and a mixed fluid of liquid and gas is repelled by the centrifugal force in the radial outside direction of the rotary drum 18 to separate the liquid,
The separated liquid is held in the liquid reservoir 26. The liquid reservoir 26 is provided with the inlet ends of the two Pitot tubes. One is drainage (excess liquid)
Line 22 and the other is a circulation line 23. The drainage line 22 is required when the processing fluid is a gas-liquid mixed fluid, but is not particularly required when the processing fluid is only gas.

An opening 25 is provided at the tip of each of the pitot pipes (drainage line, circulation line) 22 and 23, and when a part of the separated liquid passes through the opening 25, it is treated as drainage and at the same time,
The other part is returned to the liquid ring pump section W via a cooler 24 provided on the circulation line 23.

Next, the operation of the liquid ring pump device will be described.

Now, the impeller 2 in the first and second stage liquid ring pumps W1 and W2
(12), rotary drum 18 and impeller in Pitot pump section P
19 is driven by the electric motor M and is rotating. Then, an external gas or gas-liquid two-phase fluid (processing fluid) in a certain pressure range is sucked from the first suction pipe 5 to the first stage liquid ring pump W1 and taken into the liquid ring pump W1. The processing fluid is compressed and pressurized, and is discharged as a mixed fluid containing a part of the sealing liquid 3 from the discharge port 9 to the second stage liquid ring pump W2 through the communication passage 6. At the same time, the second processing fluid having a pressure different from that of the processing fluid (P ₁ ≦ P ₂ ) is sucked from the second suction pipe 8 and merges with the discharged mixed fluid to generate the second processing fluid. It is taken into the liquid ring pump W2 at the stage, where it is compressed and pressurized, and is pumped from its discharge port 15 to the pitot pump section P via the communication passage 16.

The fluid that has entered the pitot pump part P is the pitot pump part P.
By the centrifugal force of the impeller 19 rotating inside, it is repelled in the radial direction of the rotating drum. Thus, the mixed fluid of gas and liquid is separated into the substrate and the liquid, and the gas passes through the exhaust port 21 of the rear wall 18C of the rotary drum 18 to the outside of the exhaust pipe 27 provided in the casing 17 of the pitot pump unit P. Is discharged.

On the other hand, the separated liquid is stored in the liquid reservoir 2 of the circumferential wall surface 18B of the rotary drum 18.
Gathered at 6 and held by the centrifugal force of the rotating drum 18 as if they were fixed to the circumferential wall surface 18B. As a result, it is possible to circulate and recover the separated liquid in the liquid ring pump unit via the pitot pipe 23 that is a circulation line without scattering the separated liquid even in a zero-gravity environment. That is, the separated liquid is pushed into the opening 25 of the Pitot tube 23 by the discharge pressure of the liquid ring pump section W, cooled by the cooler 24 which is a cooling means provided on the way, and then returned to the liquid ring pump section W. . Then, it is sucked into the liquid ring pump portion W and functions again as the liquid seal 3 (13).

Since the vapor pressure of the sealing liquid has a great influence on the performance of the liquid sealing pump,
Since it is advantageous to lower the temperature of the sealing liquid, it is better to cool the separated liquid and return it to the liquid sealing pump section as described above. Instead of the cooler 24, this cooling means may be provided with a jacket in the liquid ring pump portion W or the pitot pump portion P to perform jacket cooling or the like.

As described above, two or more kinds of fluids having different pressure ranges (for example, gas-liquid two-phase fluid) can be simultaneously processed by one liquid ring pump device, so that the entire device can be made extremely compact. This is more advantageous as the processing fluids having different pressure regions increase.

Further, since the separated liquid is circulated and used, it is unnecessary to replenish the sealing liquid, which is the working liquid of the liquid ring pump, from the outside, which contributes to simplification of the apparatus itself. Especially, in space such as a space station, this is a great merit because replenishment of liquid is not easy.

〔The invention's effect〕

According to the liquid ring pump device according to the present invention described above, since the pitot pump unit having the centrifugal gas-liquid separation function is integrally incorporated in the multistage compression type liquid ring pump unit, for example, two or more kinds of pressure ranges are different. Transfer, circulation, mixing of gas-liquid two-phase fluid,
When applied to a gas-liquid separation / recovery process, simplification, miniaturization and weight reduction of the entire system can be achieved. If the number of process fluids having different pressure ranges increases, the number of stages of the liquid ring pumps may be changed according to the number of process fluids, so that the system can be easily handled.

In addition, since the liquid is separated by using the forced centrifugal force of the pitot pump unit, the separation of gas and liquid is ensured even in a weightless environment such as a space station.

Further, since the separated liquid is circulated and collected and reused as the sealing liquid, it is not necessary to supplement the sealing liquid from the external system, and the apparatus can be further simplified.

[Brief description of drawings]

The drawing shows a conceptual view of the whole liquid ring pump device according to the present invention. 3,13 ... Sealing liquid, 5, 8 ... Suction pipe, 18 ... Rotating drum, 26 ... Liquid reservoir, 19 ... Impeller, 20 ... Opening, 21 ...
… Exhaust port, 23… Pitot tube (circulation line), 24… Cooler (means), W… Liquid ring pump section, W1, W2… Liquid ring pump, P… Pitot pump section.

Claims (1)

[Claims] 1. A multistage compression type liquid ring pump unit having a plurality of impellers and a Pitot pump unit are directly connected by the same drive shaft, and the liquid ring pump has two stages in addition to a fluid inlet at the first stage compression stage. A fluid inlet capable of sucking a fluid from the outside is provided in any intermediate compression stage after the compression stage, and the fluid discharge port of the final compression stage and the fluid inlet of the pitot pump part are connected to each other. A rotary drum mounted on the drive shaft is provided in the casing of the casing, and an opening for inflowing a gas-liquid mixed fluid, an exhaust port for separated gas, and a liquid reservoir portion are formed on the circumferential surface of the rotary drum in the rotary drum wall. In addition, an impeller is provided in the rotary drum so that the inflowing fluid is directed outward in the radial direction of the rotary drum, and an opening portion of the pitot tube is arranged in the liquid reservoir, and the outlet side of the pitot tube is cooled by a cooling means. Through the liquid ring pump section Liquid ring pump apparatus characterized by being connected to the compression stage.