Deliquid system and method for desorbed gas

Abstract

The invention discloses a liquid removal system and method for desorbed gas, the liquid removal system comprises a liquid seal type driving unit, a liquid removal unit and a condensate circulating unit, the liquid seal type driving unit is used for driving the desorbed gas to flow, and the desorbed gas carries liquid through the liquid seal type driving unit; the liquid removing unit is communicated with the discharging part of the liquid sealing type driving unit and is used for removing liquid in the desorbed gas; and the condensate circulating unit is used for communicating the liquid discharge part of the liquid removal unit with the liquid seal type driving unit so as to return the removed liquid to the liquid seal type driving unit. Compared with the prior art, the invention has the advantages that the workload of operators can be reduced, the consumption of a liquid seal medium of the liquid seal type driving unit and the sewage yield are reduced, and the liquid seal type driving unit is safe and environment-friendly.

Description

Technical Field

[0001] The invention relates to the technical field of gas adsorption separation, and in particular to a deliquescence system and method for desorbed gas. Background Art

[0002] In the prior art, such as Figure 1 As shown, the pressure swing adsorption hydrogen purification process using a water ring vacuum pump is used. The desorbed gas (gas desorbed from the PSA adsorbent, including reverse desorbed gas and vacuum desorbed gas, which passes through a water ring vacuum pump in the process) contains a lot of liquid phase, which accumulates at the desorbed gas compressor inlet and the interstage buffer tank. The standby machine does not operate for a long time, and there is a lot of liquid accumulation. In an emergency, it cannot be started immediately. The current PSA units are deliquified in the following way: the deliquated gas compressor inlet pipeline and the interstage buffer tank boundary package guide are manually deliquated regularly on-site; however, the deliquation is removed once every 2 hours, which increases the workload of operators and the consumption of desalted water; second, the deliquated liquid enters the oily sewage system, increasing the sewage treatment volume; third, the condensate at the compressor inlet is dissolved with combustible gas, and direct deliquation on-site is unsafe and unenvironmentally friendly. Deliquation to the flare will cause the desorbed gas to leak into the flare system. Summary of the invention

[0003] The purpose of the present invention is to overcome the following problems existing in the prior art of manual periodic on-site dehydration: first, dehydration is performed once every 2 hours, which increases the workload of operators and the consumption of desalted water; second, the dehydrated liquid enters the oily sewage system, increasing the sewage treatment volume; third, if combustible gas is dissolved in the condensate at the compressor inlet, direct on-site dehydration is unsafe and environmentally friendly, and dehydration to the flare will cause the desorbed gas to leak into the flare system. A dehydration system and method for desorbed gas are provided, which can reduce the workload of operators, reduce the consumption of liquid sealing medium and sewage production of the liquid-sealed drive unit, and have the advantages of safety and environmental protection.

[0004] In order to achieve the above object, the present invention discloses a dehydration system for desorbed gas, the dehydration system for desorbed gas comprising:

[0005] A liquid-sealed driving unit, used for driving the desorbed gas to flow, wherein the desorbed gas carries liquid through the liquid-sealed driving unit;

[0006] A liquid removal unit, connected to the discharge portion of the liquid-sealed drive unit, for removing liquid from the desorbed gas;

[0007] The condensate circulation unit is used to connect the liquid discharge part of the deliquidation unit with the liquid-sealed driving unit so as to return the removed liquid to the liquid-sealed driving unit.

[0008] In some embodiments of the present invention, the condensate circulation unit is installed with an isolation member for preventing liquid from returning to the liquid-sealed drive unit during maintenance.

[0009] In some embodiments of the present invention, the condensate circulation unit is equipped with a check piece for preventing the desorbed gas in the liquid-sealed drive unit from escaping to the deliquescence unit through the condensate circulation unit.

[0010] In some embodiments of the present invention, the dehydration unit includes at least one dehydration group, each of the dehydration groups includes: a dehydration gas compressor and an interstage buffer tank which are sequentially connected along the dehydration gas flow direction, wherein the dehydration gas inlet of the dehydration gas compressor is provided with a first condensate discharge pipeline, the interstage buffer tank is provided with a second condensate discharge pipeline, and the condensate discharge part of the dehydration unit includes the first condensate discharge pipeline and the second condensate discharge pipeline.

[0011] In some embodiments of the present invention, the condensate circulation unit includes at least one condensate circulation pipe.

[0012] In some embodiments of the present invention, the desorption gas deliquification system comprises: a water ring vacuum pump and a buffer tank connected to each other, the buffer tank is connected to at least one deliquification group, the water ring vacuum pump is provided with a desorption gas feed pipeline, and the buffer tank is provided with a third condensate discharge pipeline;

[0013] Each deliquoring group is equipped with at least one condensate circulation pipe, wherein the condensate circulation pipe connects the first condensate discharge pipeline, the second condensate discharge pipeline and the third condensate discharge pipeline with the water ring vacuum pump.

[0014] In some embodiments of the present invention, the dehydration group connected to the buffer tank includes an operating dehydration group and a standby dehydration group, and the standby dehydration group is kept in a normally open state.

[0015] In some embodiments of the present invention, the condensate circulation unit is equipped with a normally open anti-blow-by component.

[0016] Another aspect of the present invention discloses a dehydration method for desorbed gas, wherein the dehydration method adopts the dehydration system for desorbed gas of the present invention, and preferably controls the pressure difference between the desorbed gas compressor and the inlet of the water ring vacuum pump to 0.01-0.08 MPa.

[0017] Through the above technical scheme, the present invention returns the removed liquid to the liquid-sealed drive unit through the condensate circulation unit. Compared with the prior art, it can reduce the workload of operators, reduce the consumption of liquid sealing medium and sewage production of the liquid-sealed drive unit, has the advantages of safety and environmental protection, and can achieve automatic, closed and loss-free liquid removal. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a deliquescence system for desorbed gas in the prior art;

[0019] Figure 2 The present invention is a deliquescence system for desorbed gas.

[0020] Description of Reference Numerals

[0021] 1 water ring vacuum pump; 2 buffer tank; 3 desorption gas compressor; 4 interstage buffer tank; 5 condensate circulation pipe; 6 desorption gas discharge pipeline; 11 desorption gas feed pipeline; 21 third condensate discharge pipeline; 31 first condensate discharge pipeline; 41 second condensate discharge pipeline; 51 isolation valve; 52 one-way valve; 53 flow limiting orifice. DETAILED DESCRIPTION

[0022] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0023] In the present invention, unless otherwise specified, directional words such as "first" and "last" generally refer to the order along the flow direction of the desorbed gas or liquid.

[0024] The present invention discloses a deliquescence system for desorbing gas, such as Figure 2 As shown, the dehydration system of the desorbed gas includes a liquid-sealed drive unit, a dehydration unit and a condensate circulation unit, wherein:

[0025] The liquid-sealed drive unit is provided with a desorbed gas feed portion for driving the desorbed gas to flow, wherein the desorbed gas carries liquid through the liquid-sealed drive unit, and the liquid includes a liquid sealing medium in the liquid-sealed drive unit;

[0026] The deliquidation unit is connected to the discharge portion of the liquid-sealed drive unit and is provided with a desorbed gas discharge portion and a condensate discharge portion, wherein when the desorbed gas from the liquid-sealed drive unit passes through the deliquidation unit, the liquid in the desorbed gas is precipitated and discharged from the condensate discharge portion, and the desorbed gas separated from the liquid is discharged from the desorbed gas discharge portion;

[0027] The condensate circulation unit is used to connect the liquid discharge part of the deliquidation unit with the liquid-sealed driving unit so as to return the removed liquid to the liquid-sealed driving unit.

[0028] In this way, the present invention returns the removed liquid to the liquid-sealed drive unit through the condensate circulation unit. Compared with the prior art, it can reduce the workload of operators, reduce the consumption of liquid sealing medium and sewage production of the liquid-sealed drive unit, and has the advantages of safety and environmental protection.

[0029] It is understandable that in some embodiments of the present invention, the desorption gas fed to the desorption gas feed part can come from a pressure swing adsorption device using a water ring vacuum pump, and the desorption gas feed part of the liquid-sealed drive unit is connected to the PSA system.

[0030] In order to prevent liquid from returning to the liquid-sealed drive unit during maintenance, in some embodiments of the present invention, the condensate circulation unit is installed with an isolation member.

[0031] In some embodiments of the present invention, the condensate circulation unit is equipped with a check piece to prevent the desorbed gas in the liquid-sealed drive unit from escaping to the deliquescence unit through the condensate circulation unit.

[0032] In some embodiments of the present invention, the liquid-sealed drive unit includes a water ring vacuum pump 1 .

[0033] In some embodiments of the present invention, the deliquidation unit includes at least one deliquidation group (it can be understood that in order to increase the processing capacity of the desorbed gas of the present invention or set up a backup processing path, multiple deliquidation groups can be set up), each deliquidation group includes: a desorbed gas compressor 3 and an interstage buffer tank 4 which are arranged in sequence along the desorbed gas flow direction, wherein the desorbed gas inlet of the desorbed gas compressor 3 is equipped with an inlet valve, and a first condensate discharge pipeline 31 is arranged in front of the inlet valve, and the interstage buffer tank 4 is provided with a second condensate discharge pipeline 41 and a desorbed gas discharge pipeline 6 (the desorbed gas discharge part of the deliquidation unit), and the condensate discharge part of the deliquidation unit includes a first condensate discharge pipeline 31 and a second condensate discharge pipeline 41.

[0034] In order to save costs while achieving the circulation function, in some embodiments of the present invention, the condensate circulation unit is configured as a condensate circulation pipe 5, and the number of the condensate circulation pipe is at least one.

[0035] In some embodiments of the present invention, Figure 2 As shown, the desorption gas deliquescence system includes: a water ring vacuum pump 1 and a buffer tank 2 which are connected to each other, and the buffer tank 2 is connected to at least one deliquescence group. It can be understood that in the prior art of the pressure swing adsorption hydrogen purification process using a water ring vacuum pump, the pressure of the water ring vacuum pump 1 is generally -0.06MPa to 0.01MPa, and the pressure of the desorption gas compressor 3 in the deliquescence group is generally 0.02MPa. The pressure difference between the desorption gas compressor and the inlet of the water ring vacuum pump is used to realize automatic deliquescence. The water ring vacuum pump 1 is provided with a desorption gas feed pipeline 11 (the desorption gas feed part of the liquid-sealed drive unit), and the buffer tank 2 is provided with a third condensate discharge pipeline 21. In the present invention, the functions of the buffer tank are to buffer the compressor inlet and to deliquify.

[0036] Each deliquidation group is equipped with at least one condensate circulation pipe 5, wherein the condensate circulation pipe 5 connects the first condensate discharge pipeline 31, the second condensate discharge pipeline 41 and the third condensate discharge pipeline 21 with the water ring vacuum pump 1 to return the liquid removed from the deliquidation group to the water ring vacuum pump 1 (hereinafter referred to as the vacuum pump).

[0037] In this way, the desorption gas dehydration system of the present invention can, on the one hand, realize automatic dehydration and greatly reduce the workload of operators; on the other hand, the condensate of the desorption gas compressor is drained from the compressor inlet to the vacuum pump inlet to realize closed and lossless dehydration, and the liquid sealing medium brought out by the vacuum pump returns to the vacuum pump inlet, thereby reducing the consumption of the vacuum pump liquid sealing medium (such as desalted water, hereinafter referred to as water), reducing the amount of sewage generated by the device, and realizing the recycling of water.

[0038] It is understandable that control valves may be provided on the first condensate discharge pipeline 31 , the second condensate discharge pipeline 41 and the third condensate discharge pipeline 21 as required, and the present invention has no special requirements for this and will not be described in detail.

[0039] In order to save costs while achieving the isolation function, in some embodiments of the present invention, the isolation member is configured as an isolation valve 51 installed on the condensate circulation pipe 5 .

[0040] In order to save costs while realizing the isolation function, the check piece is set as a one-way valve 52 installed on the condensate circulation pipe 5. In this way, it is possible to prevent the gas-liquid separator in the vacuum pump from being full and flowing to the desorption gas compressor.

[0041] In some embodiments of the present invention, Figure 2 As shown, the deliquidation group connected to the buffer tank 2 includes an operating deliquidation group and a standby deliquidation group. The operating deliquidation group and the standby deliquidation group are connected in parallel and the feed ends are both connected to the buffer tank. Each deliquidation group is respectively equipped with a condensate circulation pipe 5. Each condensate circulation pipe 5 is connected to the first condensate discharge pipeline 31, the second condensate discharge pipeline 41 and the third condensate discharge pipeline 21 of the corresponding deliquidation group, and the discharge end of the condensate circulation pipe is connected to the desorption gas inlet of the water ring vacuum pump 1, wherein the standby deliquidation group is kept in a normally open state.

[0042] In this way, the access point is selected at the desorption gas inlet of the vacuum pump, which does not affect the operation of the adsorption tower system and the desorption gas compressor.

[0043] Keeping the dehydration process of the standby dehydration group open can prevent condensate from entering the oily wastewater and flare system, and prevent the desorbed gas from being discharged into the atmosphere and flare, which is safer and more environmentally friendly. It can also ensure that the standby dehydration gas compressor is free of condensate, shorten the startup time, and eliminate the risk of standby compressor collision.

[0044] It should be noted that the normally open standby degassing process can easily cause the gas phase of the buffer tank to enter the vacuum pump, resulting in a decrease in the vacuum pumping capacity of the PSA system and affecting the adsorbent regeneration effect. For this reason, in some embodiments of the present invention, the condensate circulation unit is equipped with a normally open anti-gas blowby component.

[0045] The present invention has no special requirements for the normally open anti-gas blowby component, as long as the blowby caused by the normally open dehydration process can be reduced as much as possible. In some embodiments of the present invention, the normally open anti-gas blowby component is configured as a flow limiting orifice plate 53 or a check valve installed on the condensate circulation pipe 5.

[0046] It is understandable that if Figure 2 As shown, the present invention installs the isolation member, the check member and the normally open anti-gas blowby member in the section of the condensate circulation pipe 5 after the liquids in the first condensate discharge pipeline 31, the second condensate discharge pipeline 41 and the third condensate discharge pipeline 21 are collected along the liquid flow direction. The present invention has no special requirements for the sequential position relationship of the isolation member, the check member and the normally open anti-gas blowby member in the condensate circulation pipe 5, which will not be elaborated herein.

[0047] Another aspect of the present invention discloses a dehydration method for desorbed gas, wherein the dehydration method adopts the dehydration system for desorbed gas of the present invention. The method of the present invention can achieve closed and lossless dehydration.

[0048] In some embodiments of the present invention, the pressure difference between the desorption gas compressor and the inlet of the water ring vacuum pump is preferably controlled to be 0.01-0.08 MPa. The pressure difference between the desorption gas compressor and the inlet of the water ring vacuum pump is used to achieve automatic dehydration.

[0049] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various specific technical features in any appropriate manner. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations. However, these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A deliquescence system for desorbing gas, It is characterized in that The deliquescence system of the desorbed gas comprises: A liquid-sealed driving unit, used for driving the desorbed gas to flow, wherein the desorbed gas carries liquid through the liquid-sealed driving unit; A liquid removal unit, connected to the discharge portion of the liquid-sealed drive unit, for removing liquid from the desorbed gas; The condensate circulation unit is used to connect the liquid discharge part of the deliquidation unit with the liquid-sealed driving unit so as to return the removed liquid to the liquid-sealed driving unit.

2. The degassing system according to claim 1, It is characterized in that The condensate circulation unit is provided with an isolator for preventing liquid from returning to the liquid-sealed drive unit during maintenance; and / or The condensate circulation unit is provided with a check piece for preventing the desorbed gas in the liquid-sealed drive unit from passing through the condensate circulation unit to the deliquescence unit.

3. The degassing system of claim 1, It is characterized in that The liquid-sealed drive unit comprises a water ring vacuum pump (1); and / or The dehydration unit comprises at least one dehydration group, each of which comprises: a dehydration gas compressor (3) and an interstage buffer tank (4) which are sequentially connected and arranged along the dehydration gas flow direction, wherein the dehydration gas inlet of the dehydration gas compressor (3) is provided with a first condensate discharge pipeline (31), the interstage buffer tank (4) is provided with a second condensate discharge pipeline (41), and the condensate discharge part of the dehydration unit comprises the first condensate discharge pipeline (31) and the second condensate discharge pipeline (41); and / or The condensate circulation unit comprises at least one condensate circulation pipe (5).

4. The deliquification system of the desorbed gas according to claim 3, It is characterized in that The desorption gas deliquification system comprises: a water ring vacuum pump (1) and a buffer tank (2) which are connected to each other, the buffer tank (2) being connected to at least one deliquification group, the water ring vacuum pump (1) being provided with a desorption gas feed pipeline (11), and the buffer tank (2) being provided with a third condensate discharge pipeline (21); Each deliquoring group is equipped with at least one condensate circulation pipe (5), wherein the condensate circulation pipe (5) connects the first condensate discharge pipeline (31), the second condensate discharge pipeline (41) and the third condensate discharge pipeline (21) to the water ring vacuum pump (1).

5. The deliquification system of the desorbed gas according to claim 4, It is characterized in that The isolating member is configured as an isolating valve (51) installed on the condensate circulation pipe (5).

6. The deliquification system of the desorbed gas according to claim 4 or 5, It is characterized in that The check member is configured as a one-way valve (52) installed on the condensate circulation pipe (5).

7. The deliquification system of the desorbed gas according to claim 6, It is characterized in that The dehydration group connected to the buffer tank (2) comprises an operating dehydration group and a standby dehydration group, and the standby dehydration group is kept in a normally open state.

8. The deliquification system of the desorbed gas according to claim 7, It is characterized in that The condensate circulation unit is equipped with normally open anti-gas blowby parts.

9. The deliquification system of the desorbed gas according to claim 8, It is characterized in that The normally open anti-gas blowby component is configured as a flow limiting orifice plate (53) or a check valve installed on the condensate circulation pipe (5).

10. A method for degassing gas, It is characterized in that The deliquescence method adopts the deliquescence system of the desorbed gas according to any one of claims 1 to 9, and preferably controls the pressure difference between the desorbed gas compressor and the inlet of the water ring vacuum pump to 0.01 to 0.08 MPa.

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