Liquid nitrogen rewarming, gasifying and discharging device

Abstract

The utility model discloses a liquid nitrogen rewarming, gasifying and discharging device which comprises a cylindrical lower barrel body, an upper barrel body arranged at an opening at the upper end of the lower barrel body, a flow guide pipe arranged at an opening at the top of the upper barrel body, a Pall ring arranged in the barrel body, and a liquid nitrogen discharging pipe and an air pipeline which are arranged on the side wall of the barrel body, a liquid distributor communicated with the liquid nitrogen discharge pipe is arranged in the lower barrel body, a rainproof cap is arranged at the top of the flow guide pipe, the Pall ring is flush with the upper edge of the lower barrel body, the upper barrel body is of a conical structure with an opening in the top, the air pipeline is connected with a compressed air source, and one end of the liquid distributor is connected with the liquid nitrogen discharge pipe. The situation that in the pre-cooling process of the air separation-cryogenic liquid nitrogen pipeline, liquid nitrogen is discharged and flows to the ground, and consequently ground facilities are damaged or personnel are frostbitten due to low temperature can be effectively avoided; and the problem that after gasified nitrogen is discharged into air, a nitrogen enrichment area is formed within a certain range, and the risk of suffocation of operators is caused can be avoided, the modification cost is low, and no maintenance cost exists.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical machinery and equipment, and particularly relates to a liquid nitrogen rewarming, gasifying and discharging device. Background Art

[0002] At present, when the cryogenic unit is in abnormal conditions, during load increase or decrease, or when the inlet temperature of the hydrogen-rich gas flash tank rises to the alarm level, it is necessary to timely supplement liquid nitrogen to the cold box to balance the rising raw gas temperature. Since the liquid nitrogen pipeline from the air separation unit to the cryogenic cold box is relatively long, if the pre-cooled and discharged liquid nitrogen does not gasify, the liquid nitrogen will flow to the ground and damage the ground facilities. After gasification, a nitrogen enrichment area will be formed, and there is a risk of asphyxiation for the operating personnel within the range. Therefore, to ensure that liquid nitrogen can be timely supplemented to the cold box within a short time, this section of the pipeline must be ensured to be always in a pre-cooled standby state. Therefore, a rewarming and gasifying device that can fully gasify liquid nitrogen and discharge it to the atmosphere at a high point is required to avoid damage to ground facilities, the risks of personnel frostbite and asphyxiation, etc. Summary of the Invention

[0003] In order to solve certain or some technical problems existing in the prior art, the purpose of this application is to provide a liquid nitrogen rewarming, gasifying and discharging device, which can effectively avoid the situation that during the pre-cooling process of the air separation - cryogenic liquid nitrogen pipeline, the liquid nitrogen discharge flows to the ground and causes low-temperature damage to the ground facilities or frostbite to personnel; and can also avoid the problem that after gasification and discharge into the air, a nitrogen enrichment area is formed within a certain range, resulting in the risk of asphyxiation for the operating personnel. The transformation cost is low and there is no maintenance cost.

[0004] To solve the above-mentioned existing technical problems, this application is implemented by adopting the following technical solutions:

[0005] A liquid nitrogen rewarming, gasifying and discharging device includes a cylindrical lower barrel body, an upper barrel body provided at the upper opening of the lower barrel body, a diversion pipe provided at the top opening of the upper barrel body, Pall rings provided in the barrel body, a liquid nitrogen discharge pipe and an air pipeline provided on the side wall of the barrel body. A liquid distributor communicated with the liquid nitrogen discharge pipe is provided in the lower barrel body. A rain-proof cap is provided at the top of the diversion pipe. The Pall rings are flush with the upper edge of the lower barrel body. The upper barrel body is a conical structure with an open top. The air pipeline is connected to a compressed air source. One end of the liquid distributor is connected to the liquid nitrogen discharge pipe.

[0006] Preferably, a temperature measuring instrument is provided on the diversion pipe.

[0007] Preferably, a circle of fixed flanges is provided on the outer side of the bottom of the lower barrel body.

[0008] Preferably, the fixed flange adopts a four-hole structure with a thickness of 10 mm.

[0009] Preferably, the lower barrel body comprises a barrel wall and a barrel bottom, and the barrel wall is made of a stainless steel plate with a thickness of 6 mm.

[0010] Preferably, the liquid distributor is The circular structure is made of stainless steel pipe.

[0011] Preferably, the liquid distributor is arranged at the upper 1 / 4 position of the lower barrel body.

[0012] Preferably, the air pipeline is Seamless steel pipe.

[0013] Preferably, the lower barrel is filled with the stainless steel ball rings.

[0014] Preferably, the diameter of the top opening of the upper barrel body is 50 mm, and one end of the guide tube is welded to the top opening of the upper barrel body.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] The liquid nitrogen rewarming gasification and discharge device can effectively prevent the air separation-cryogenic liquid nitrogen pipeline from discharging liquid nitrogen to the ground during the pre-cooling process, causing low temperature damage to ground facilities or frostbite to personnel; it also shortens the time for balancing the temperature of the raw gas in the cold box by replenishing liquid nitrogen, ensuring the smooth operation of the device, and avoiding the formation of nitrogen-enriched areas within a certain range after gasification and discharge into the air, which may cause the risk of suffocation to operators. The transformation cost is low and there is no maintenance cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the structure of the utility model;

[0018] In the figure: 1. fixing flange; 2. lower barrel body; 21. barrel wall; 22. barrel bottom; 3. ball ring; 4. liquid distributor; 5. flow guide pipe; 6. temperature measuring instrument; 7. rain cap; 8. upper barrel body; 9. liquid nitrogen discharge pipe; 10. air pipeline. DETAILED DESCRIPTION

[0019] Below, the present application is further described in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0020] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present application.

[0021] The terms "first", "second", etc. in the present application are used to distinguish similar objects, rather than to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here. And the objects distinguished by "first", "second", etc. are usually of the same type, and do not limit the number of objects. For example, the first object can be one or multiple. In addition, "and / or" in the specification and claims means at least one of the connected objects. The character " / ", generally represents an "or" relationship between the associated objects before and after.

[0022] As Figure 1 shown, a liquid nitrogen rewarming, gasifying and discharging device includes a cylindrical lower barrel body 2, an upper barrel body 8 provided at the upper end opening of the lower barrel body 2, a diversion pipe 5 provided at the top opening of the upper barrel body 8, a Pall ring 3 provided in the barrel body, a liquid nitrogen discharge pipe 9 and an air pipeline 10 provided on the side wall of the barrel body. A liquid distributor 4 communicating with the liquid nitrogen discharge pipe 9 is provided in the lower barrel body 2. A rain cap 7 is provided at the top of the diversion pipe 5. The Pall ring 3 is flush with the upper edge of the lower barrel body 2. The upper barrel body 8 is a conical structure with an open top. The air pipeline 10 is connected to a compressed air source. One end of the liquid distributor 4 is connected to the liquid nitrogen discharge pipe 9.

[0023] During actual use, the liquid nitrogen rewarming, gasifying and discharging device is connected to the in-service compressed air inlet valve through the air pipeline 10 and is communicated with the in-service liquid nitrogen discharge valve through the nitrogen discharge pipe. The liquid nitrogen discharge flow rate is controlled by the opening degree of the pre-cooling pipeline temperature control valve (≤ -196 °C), and the compressed air inlet flow rate is controlled by the temperature of the temperature measuring point of the high-point discharge pipe (≥ -20 °C) to control the opening degree. Take a section of material S30403. A seamless stainless steel pipe with a length of 3500 mm is used as the diversion pipe 5 and is welded to the upper end of the upper barrel body 8. A rain cap 7 is made at the top of the diversion pipe 5. After the low-temperature liquid nitrogen enters the lower barrel body 2 through the liquid nitrogen discharge pipe 9, it is first shunted by the liquid distributor 4 into the interior of the lower barrel body 2. After heat exchange with the normal-temperature nitrogen or compressed air in the lower barrel body 2, the low-temperature liquid nitrogen is vaporized, and then discharged from the top of the diversion pipe 5 at a high point. During the discharge, the rain cap 7 can not only block the entry of external rainwater, etc., but also perform shunting, so that the low-temperature nitrogen can effectively avoid the situation that the liquid nitrogen in the air separation-deep cooling liquid nitrogen pipeline flows to the ground during the pre-cooling process, resulting in low-temperature damage to ground facilities or frostbite of personnel; at the same time, it also shortens the time for supplementing liquid nitrogen to balance the temperature of the raw gas in the cold box, ensures the stable operation of the device, and can also avoid the problem of the formation of a nitrogen enrichment area within a certain range after gasification and discharge into the air, resulting in the risk of asphyxiation for operating personnel. The transformation cost is low and there is no maintenance cost.

[0024] Further improvement is that a temperature measuring instrument 6 is provided on the diversion pipe 5.

[0025] The temperature measuring instrument 6 is installed at the position 1 / 5 down from the top of the diversion pipe 5. Through the temperature measuring instrument 6, the temperature of the nitrogen discharged outward can be detected in a timely manner. When the detected temperature is too low, the inflow rate of the low-temperature nitrogen can be adjusted to effectively vaporize the low-temperature nitrogen.

[0026] Further improvement is that a circle of fixed flanges 1 is provided on the outer side of the bottom of the lower barrel body 2; the lower barrel body 2 includes a barrel wall 21 and a barrel bottom 22, and the barrel wall 21 is rolled from a stainless steel plate with a thickness of 6 mm The fixed flange 1 adopts a four-hole structure with a thickness of 10 mm.

[0027] The lower barrel body 2 is made of S30403 stainless steel plate with a thickness of 6 mm and rolled into a circular barrel wall with a height of 1000 mm, and the bottom is made of a stainless steel plate of the same specification as the barrel bottom 22 and welded and sealed. A four-hole fixed flange 1 with an inner diameter of 600 mm, an outer diameter of 700 mm, and a thickness of 10 mm is welded to the outer circle of the bottom for ground fixing, which can make the production of the lower barrel body 2 more convenient, with lower production cost, better corrosion resistance, higher firmness, and convenient assembly and firm positioning.

[0028] Further improvement is that the liquid distributor 4 is made of a circular structure made of stainless steel pipe; the liquid distributor 4 is arranged at the 1 / 4 position in the upper part of the lower barrel body 2.

[0029] Using the material S30403, A circular liquid distributor 4 is made of stainless steel pipe. The size of the distributor is slightly smaller than the inner diameter of the barrel body and is installed at the upper 1 / 4 position of the lower barrel body 2. The outlet is connected to the liquid nitrogen discharge pipe 9, which can make the nitrogen more evenly distributed when entering the lower barrel body 2.

[0030] Further improvement is that the air pipeline 10 is seamless steel pipe.

[0031] At a position 100 mm above the bottom of the lower barrel body 2, a compressed air pipeline 10 is welded through an opening. The material is S30403, seamless steel pipe, which has higher firmness, longer service life and better anti-deformation ability.

[0032] Further improvement is that the lower barrel body 2 is filled with the Pall rings 3 made of stainless steel.

[0033] Further improvement is that the diameter of the opening at the top of the upper barrel body 8 is 50 mm, and one end of the diversion pipe 5 is welded at the opening at the top of the upper barrel body 8.

[0034] The upper barrel body 8 with a conical shape with an upper hole diameter of 50 mm, a lower hole diameter of 600 mm and a height of 800 mm is rolled from a stainless steel plate with the same specifications as the material of the lower barrel body 2 and is fully welded to the upper end of the lower barrel body 2.

[0035] The above embodiments are only the preferred embodiments of the present application and cannot be used to limit the protection scope of the present application. Any non-substantial changes and substitutions made by those skilled in the art based on the present application belong to the protection scope required by the present application.

Claims

1. A liquid nitrogen rewarming gasification discharge device, characterized in that: The invention comprises a cylindrical lower barrel body (2), an upper barrel body (8) provided at an opening at the upper end of the lower barrel body (2), a flow guide pipe (5) provided at the top opening of the upper barrel body (8), a ball ring (3) provided in the barrel body, a liquid nitrogen discharge pipe (9) and an air pipeline (10) provided on the side wall of the barrel body, wherein a liquid distributor (4) connected to the liquid nitrogen discharge pipe (9) is provided in the lower barrel body (2), a rainproof cap (7) is provided on the top of the flow guide pipe (5), the ball ring (3) is flush with the upper edge of the lower barrel body (2), the upper barrel body (8) is a conical structure with an opening at the top, the air pipeline (10) is connected to a compressed air source, and one end of the liquid distributor (4) is connected to the liquid nitrogen discharge pipe (9).

2. A liquid nitrogen rewarming gasification discharge device according to claim 1, characterized in that: The flow guide tube (5) is provided with a temperature measuring instrument (6).

3. The liquid nitrogen rewarming gasification discharge device according to claim 1, characterized in that: A fixing flange (1) is arranged on the outer side of the bottom of the lower barrel (2).

4. A liquid nitrogen rewarming gasification discharge device according to claim 3, characterized in that: The fixing flange (1) adopts a four-hole structure with a thickness of 10 mm.

5. The liquid nitrogen rewarming gasification discharge device according to claim 1, characterized in that: The lower barrel body (2) comprises a barrel wall (21) and a barrel bottom (22), wherein the barrel wall (21) is made of a stainless steel plate with a thickness of 6 mm.

6. The liquid nitrogen rewarming gasification discharge device according to claim 1, characterized in that: The liquid distributor (4) is composed of The circular structure is made of stainless steel pipe.

7. The liquid nitrogen rewarming gasification discharge device according to claim 6, characterized in that: The liquid distributor (4) is arranged at the upper 1 / 4 position of the lower barrel body (2).

8. The liquid nitrogen rewarming gasification discharge device according to claim 1, characterized in that: The air pipeline (10) is Seamless steel pipe.

9. The liquid nitrogen rewarming gasification discharge device according to claim 1, characterized in that: The lower barrel (2) is filled with the stainless steel ball rings (3).

10. The liquid nitrogen rewarming gasification discharge device according to claim 1, characterized in that: The diameter of the top opening of the upper barrel body (8) is 50 mm, and one end of the flow guide tube (5) is welded to the top opening of the upper barrel body (8).

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