Novel pre-cooling spraying system for low-temperature liquefied gas storage tank

Abstract

A novel pre-cooling spraying system for a low-temperature liquefied gas storage tank is characterized by comprising a cooling spraying pipeline and nozzles installed on the cooling spraying pipeline, the cooling spraying pipeline comprises an outer ring pipeline and an inner ring pipeline, outer ring nozzles are installed on the outer ring pipeline, inner ring nozzles are installed on the inner ring pipeline, and the outer ring nozzles are communicated with the inner ring nozzles. The outer ring pipeline and the inner ring pipeline are hung on a suspended ceiling at the top of the tank body through a pipeline support, and cooling fluid is led into a cooling fluid inlet in the center of the inner ring pipeline from the outside of the tank body through a pipeline and then flows into an inner ring nozzle on the inner ring pipeline through a radial pipeline. The cooling fluid further flows into the outer ring pipeline through a radial pipeline communicating the outer ring pipeline with the inner ring pipeline and flows out of an outer ring nozzle installed on the outer ring pipeline. The pre-cooling device can reduce the temperature at a relatively constant speed, improve the temperature field and the atomization effect at the cooling stage, and avoid the dripping leakage of the nozzle, thereby improving the pre-cooling effect of the storage tank.

Description

Technical Field

[0001] The utility model belongs to the technical field of cryogenic liquefied gas storage tanks, in particular to a large-scale storage tank atomization precooling spray system with a uniformly distributed flow diversion function, specifically a novel precooling spray system for cryogenic liquefied gas storage tanks. Background Art

[0002] The precooling process of membrane type cryogenic liquefied gas storage tanks is a key step in the tank commissioning process. The precooling spray system is the main functional system for precooling the tanks. At present, the trend of large-scale cryogenic storage tanks is becoming more and more intense, and the tank capacity is gradually increasing. As a result, the precooling spray flow rate requirements of the tanks are getting larger and larger.

[0003] As the volume of storage tanks is getting larger and larger, and the type of cryogenic liquid storage tanks is usually cylindrical, the traditional pre-cooling spray system has only one circular cooling pipe, and the distance between the tank wall and the tank bottom and the spray system is not equal, which easily leads to inconsistent cooling temperatures of the tank wall and the tank bottom. The nozzle pre-cooling effect of the traditional spray system is not good. The pre-cooling of large-volume storage tanks is uneven and insufficient. The nitrogen in the tank will roll up and down due to uneven cooling. The uneven temperature in the tank will cause uneven cold shrinkage stress of the film in the tank. In severe cases, the inner wall film may be damaged.

[0004] In addition, the structure of the traditional precooling nozzle is easy to be blocked, and the spray angle cannot fully cover the inside of the tank, which is also an important reason for the poor cooling effect inside the tank. The dripping phenomenon of the traditional precooling nozzle is relatively common. In the initial precooling stage, the low-temperature liquid drips to the bottom of the tank, causing the local temperature of the film steel plate at the bottom of the tank to drop rapidly, resulting in low-temperature stress shrinkage of the film steel plate at the bottom of the tank. In severe cases, it may cause cracks in the weld. Utility Model Content

[0005] The utility model aims to solve the problem of uneven spray cooling temperature of existing cryogenic liquefied gas storage tanks and designs a novel pre-cooling spray system for cryogenic liquefied gas storage tanks. The spray system can uniformly reduce the temperature of the film storage tank tube wall and the tank bottom, improve the temperature field and atomization effect in the cooling stage, avoid nozzle dripping, and thus improve the pre-cooling effect of the storage tank.

[0006] The new technical solution of this utility model is:

[0007] A novel precooling spray system for cryogenic liquefied gas storage tanks is characterized in that it includes a cooling spray pipe 3 and a nozzle installed thereon, wherein the cooling spray pipe enters from a reserved pipe opening on the tank top and is arranged below the suspended ceiling; the cooling spray pipe is fixed to the suspended ceiling by a support. The cooling spray pipe includes an outer ring pipe and an inner ring pipe, an outer ring nozzle is installed on the outer ring pipe, and an inner ring nozzle is installed on the inner ring pipe. The outer ring pipe and the inner ring pipe are suspended on the suspended ceiling on the top of the tank body through a pipe bracket, and the cooling fluid is introduced from the outside of the tank body through a pipe into the cooling fluid inlet at the center of the inner ring pipe, and then flows into the inner ring nozzle on the inner ring pipe through a radial pipe. At the same time, the cooling fluid flows into the outer ring pipe through a radial pipe connecting the outer ring pipe and the inner ring pipe and flows out from the outer ring nozzle installed on the outer ring pipe.

[0008] Furthermore, the cooling fluid inlet pipe can enter the cooling spray pipeline in the tank from the tank top through the sleeve, and the cooling fluid inlet can be located at the center of the ceiling.

[0009] The number of the outer ring nozzles and the inner ring nozzles is determined according to the size of the storage tank. Furthermore, the number of the outer ring nozzles is greater than the number of the inner ring nozzles.

[0010] The inner ring nozzle is arranged on the inner ring pipe, and comprises an inner ring nozzle mounting structure, an inner ring nozzle flow guide structure and an inner ring nozzle. The inner ring nozzle is mounted on the inner ring nozzle mounting structure through an inner ring nozzle mounting nut, and each inner ring nozzle is provided with an inner ring nozzle first tapered cavity, an inner ring nozzle second tapered cavity and an inner ring nozzle third tapered cavity. The inner ring nozzle flow guide structure can ensure that the fluid flow entering each inner ring nozzle is the same.

[0011] For example, the number of inner ring nozzles in each inner ring nozzle can be five; the arrangement angle of the five inner ring nozzles can be 45 degrees. Based on the above embodiment, the spray can cover 180 degrees; the spray of each nozzle is in a 45-degree fan shape, ensuring that the spray is evenly distributed in the area inside the inner and outer rings and between the inner and outer rings.

[0012] The outer ring nozzle is arranged on the outer ring pipeline, and comprises an outer ring nozzle mounting structure, an outer ring nozzle flow guide structure and an outer ring nozzle. The outer ring nozzle is fixedly mounted on the outer ring nozzle mounting structure through an outer ring nozzle mounting nut, and each outer ring nozzle is provided with an outer ring nozzle first tapered cavity, an outer ring nozzle second tapered cavity and an outer ring nozzle third tapered cavity. The outer ring nozzle flow guide structure can ensure that the fluid flow entering each outer ring nozzle is the same.

[0013] The number of outer ring nozzles in each outer ring nozzle is three, and the arrangement angle of the outer ring nozzles is 45 degrees. The arrangement angle of the three outer ring nozzles is 45 degrees, and the spray can cover the direction of 90 degrees; the spray of each outer ring nozzle is in a 45-degree fan shape, which can ensure that the spray outside the outer ring is evenly distributed.

[0014] The beneficial effects of the utility model are:

[0015] The cooling spray system described in the utility model is composed of an outer ring pipeline and an inner ring pipeline. The pipeline is fixed on the ceiling by a bracket. The cooling fluid enters from the liquid inlet located in the center of the ceiling. The nozzles arranged on the outer ring pipeline and the inner ring pipeline can improve the overall atomization effect, optimize the spray range, and ensure the internal cooling effect of large-volume storage tanks.

[0016] The inner ring nozzle and the outer ring nozzle described in the utility model are both provided with a flow guide structure inside the nozzle, and the structure can evenly distribute the fluid entering the nozzle to the nozzle head, optimize the spray effect of the nozzle, and avoid the phenomenon of uneven nozzle.

[0017] The angles and numbers of the nozzles arranged by the inner ring nozzle and the outer ring nozzle of the utility model all take into account the characteristics of the inner ring pipeline and the outer ring pipeline, reduce the spray dead zone and the overlapping zone, optimize the spray effect, and eliminate the nitrogen tumbling swirl caused by the excessive temperature difference in the tank.

[0018] The inner ring nozzle and the outer ring nozzle described in the utility model both adopt the structure of a first tapered cavity, a second tapered cavity, and a third tapered cavity. Through the three-stage tapering, the cooling fluid can form a finer spray to prevent uneven cooling of the tank top caused by dripping.

[0019] The cooling spray system of the utility model can reduce the temperature at a relatively uniform speed, improve the temperature field and atomization effect in the tank during the cooling stage, avoid nozzle dripping, and thus improve the pre-cooling effect of the storage tank. The utility model can achieve a cooling rate of no more than 3°C / hour in the pre-cooling of a large storage tank, and a temperature difference of no more than 30°C between any two adjacent thermocouples on the tank wall or tank bottom. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a side view of the cooling spray system of an embodiment of the utility model.

[0021] Figure 2 It is a top view of the cooling spray system of an embodiment of the utility model.

[0022] Figure 3 It is a cross-sectional view of the inner ring nozzle of an embodiment of the utility model.

[0023] Figure 4 It is a cross-sectional view of the outer ring nozzle of an embodiment of the utility model.

[0024] In the figure, 1, liquefied gas storage tank, 2, suspended ceiling, 3, cooling spray pipe, 4, pipe support, 5, cooling fluid inlet, 31, inner ring nozzle, 32-outer ring nozzle. 311, inner ring nozzle mounting structure, 312, inner ring nozzle guide structure, 313, inner ring nozzle first tapered cavity, 314, inner ring nozzle mounting nut, 315, inner ring nozzle second tapered cavity, 316, inner ring nozzle third tapered cavity. 321, outer ring nozzle mounting structure, 322, outer ring nozzle guide structure, 323, outer ring nozzle first tapered cavity, 324, outer ring nozzle mounting nut, 325, outer ring nozzle second tapered cavity, 326, outer ring nozzle third tapered cavity. DETAILED DESCRIPTION

[0025] The specific embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. The following embodiments are provided in order to enable a more thorough understanding of the present invention.

[0026] like Figure 1-4 shown.

[0027] A novel precooling spray system for cryogenic liquefied gas storage tanks, which consists of a cooling spray pipe 3 and a nozzle installed thereon, wherein the cooling spray pipe 3 includes an outer ring pipe and an inner ring pipe, an outer ring nozzle 32 is installed on the outer ring pipe, and an inner ring nozzle 31 is installed on the inner ring pipe. Figure 2 As shown, the outer ring pipeline and the inner ring pipeline are suspended on the ceiling 2 on the top of the tank body 1 through the pipeline support 4, as shown in FIG. Figure 1 As shown, the cooling fluid is introduced from the outside of the tank body 1 through a pipe into the cooling fluid inlet 5 at the center of the inner ring pipe, and then flows into the inner ring nozzle 31 on the inner ring pipe through a radial pipe. At the same time, the cooling fluid flows into the outer ring pipe through a radial pipe connecting the outer ring pipe and the inner ring pipe and flows out from the outer ring nozzle 32 installed on the outer ring pipe. The number of the outer ring nozzles is greater than the number of the inner ring nozzles. The structure of the inner ring nozzle 31 of the utility model is as follows Figure 3 As shown, they are arranged on the inner ring pipe, and consist of an inner ring nozzle mounting structure 311, an inner ring nozzle flow guide structure 312 and an inner ring nozzle. The inner ring nozzle is mounted on the inner ring nozzle mounting structure 311 through an inner ring nozzle mounting nut 314. Each inner ring nozzle is provided with an inner ring nozzle first tapered cavity 313, an inner ring nozzle second tapered cavity 315 and an inner ring nozzle third tapered cavity 316. The number of inner ring nozzles in each inner ring nozzle 31 is five, and the inner ring nozzle flow guide structure 312 can ensure that the fluid flow entering each inner ring nozzle is the same; the arrangement angle of the five nozzles is 45 degrees, and the spray can cover 180 degrees; the spray of each nozzle is in a 45-degree fan shape, ensuring that the spray is evenly distributed in the area within the inner and outer rings and between the inner and outer rings. The structure of the outer ring nozzle 32 of the utility model is as shown in FIG. Figure 4As shown, they are arranged on the outer ring pipeline, and are composed of an outer ring nozzle mounting structure 321, an outer ring nozzle flow guide structure 322 and an outer ring nozzle. The outer ring nozzle is fixedly mounted on the outer ring nozzle mounting structure 321 through an outer ring nozzle mounting nut 324, and each outer ring nozzle is provided with an outer ring nozzle first tapered cavity 323, an outer ring nozzle second tapered cavity 325 and an outer ring nozzle third tapered cavity 326. The number of outer ring nozzles in each outer ring nozzle 32 is three, and they can ensure the same fluid flow entering each outer ring nozzle through the outer ring nozzle flow guide structure 322. The arrangement angle of the three outer ring nozzles is 45 degrees, and the spray can cover a 90-degree direction; the spray of each outer ring nozzle is in a 45-degree fan shape, which can ensure that the spray is evenly distributed in the area outside the outer ring.

[0028] Details are as follows:

[0029] like Figure 1 and Figure 2 As shown, the cooling spray pipe enters from the reserved pipe opening on the tank top and is arranged below the suspended ceiling 2; the cooling spray pipe 3 is fixed on the suspended ceiling by a pipe bracket 4;

[0030] The cooling spray pipeline is composed of an outer ring pipeline, an inner ring pipeline, and a radial pipeline. The cooling fluid inlet is located at the center of the spray pipeline, wherein:

[0031] The nozzle is arranged on the cooling spray pipe 3, and the cooling spray pipe is divided into an outer ring pipe and an inner ring pipe; the outer ring pipe and the inner ring pipe are connected by a radial pipe; the nozzle is divided into an outer ring nozzle 32 and an inner ring nozzle 31; the number of the outer ring nozzle 32 and the inner ring nozzle 31 is determined according to the size of the storage tank, and the number of the outer ring nozzle is greater than the number of the inner ring nozzle.

[0032] like Figure 3 The inner ring nozzle 31 is arranged on the inner ring pipe, and is composed of an inner ring nozzle mounting structure, a nozzle flow guide structure, a first nozzle tapered cavity, a nozzle mounting nut, a second nozzle tapered cavity, and a third nozzle tapered cavity. The outer ring nozzle is arranged on the outer ring pipe, and is composed of an outer ring nozzle mounting structure, a nozzle flow guide structure, a first nozzle tapered cavity, a nozzle mounting nut, a second nozzle tapered cavity, and a third nozzle tapered cavity.

[0033] The cooling fluid pipeline can enter the cooling spray pipeline inside the tank from the tank top through the sleeve, and the inlet of the cooling fluid is located at the center of the ceiling.

[0034] The outer ring pipeline and the inner ring pipeline are connected by radial pipelines, and the cooling fluid enters the outer ring pipeline and the inner ring pipeline through the radial pipelines.

[0035] like Figure 3The inner ring nozzle 31 is composed of five nozzles, and a flow guide structure is arranged inside the nozzle to ensure that the fluid flow entering each nozzle is the same. The five nozzles are arranged at an angle of 45 degrees, and the spray can cover 180 degrees. Furthermore, the spray of each nozzle is in a 45-degree fan shape, which can ensure that the spray is evenly distributed in the area between the inner and outer rings and between the inner and outer rings.

[0036] like Figure 4 The outer ring nozzle 32 shown is composed of three nozzles, and a flow guide structure is arranged inside the nozzle to ensure that the fluid flow entering each nozzle is the same. The three nozzles are arranged at an angle of 45 degrees, and the spray can cover a 90-degree direction. Furthermore, the spray of each nozzle is in a 45-degree fan shape, which can ensure that the spray is evenly distributed in the area outside the outer ring.

[0037] The parts not involved in the present invention are the same as the prior art or can be implemented by using the prior art.

Claims

1. A new type of precooling spray system for cryogenic liquefied gas storage tanks, characterized in that: It comprises a cooling spray pipe (3) and a nozzle mounted thereon, the cooling spray pipe (3) comprising an outer ring pipe and an inner ring pipe, the outer ring pipe being mounted with an outer ring nozzle (32), the inner ring pipe being mounted with an inner ring nozzle (31), the outer ring pipe and the inner ring pipe being suspended on a suspended ceiling (2) at the top of a tank body (1) via a pipe bracket (4), a cooling fluid is introduced from the outside of the tank body (1) into a cooling fluid inlet (5) at the center of the inner ring pipe through a pipe, and then flows into the inner ring nozzle (31) on the inner ring pipe through a radial pipe, the cooling fluid flows into the outer ring pipe through a radial pipe connecting the outer ring pipe and the inner ring pipe, and flows out from the outer ring nozzle (32) mounted on the outer ring pipe.

2. The novel precooling spray system for cryogenic liquefied gas storage tanks according to claim 1 is characterized in that: The number of the outer ring nozzles is greater than the number of the inner ring nozzles.

3. The novel precooling spray system for cryogenic liquefied gas storage tanks according to claim 1 is characterized in that: The inner ring nozzle (31) is arranged on the inner ring pipe, and the inner ring nozzle (31) comprises an inner ring nozzle mounting structure (311), an inner ring nozzle flow guide structure (312), and an inner ring nozzle. The inner ring nozzle is mounted on the inner ring nozzle mounting structure (311) via an inner ring nozzle mounting nut (314), and each inner ring nozzle is provided with an inner ring nozzle first tapered cavity (313), an inner ring nozzle second tapered cavity (315), and an inner ring nozzle third tapered cavity (316).

4. The novel precooling spray system for cryogenic liquefied gas storage tanks according to claim 3 is characterized in that: The number of inner ring nozzles in each inner ring nozzle (31) is five; the five inner ring nozzles are arranged at an angle of 45 degrees.

5. The novel precooling spray system for cryogenic liquefied gas storage tanks according to claim 1 is characterized in that: The outer ring nozzle (32) is arranged on the outer ring pipeline, and comprises an outer ring nozzle mounting structure (321), an outer ring nozzle flow guide structure (322) and an outer ring nozzle. The outer ring nozzle is fixedly mounted on the outer ring nozzle mounting structure (321) via an outer ring nozzle mounting nut (324), and each outer ring nozzle is provided with an outer ring nozzle first tapered cavity (323), an outer ring nozzle second tapered cavity (325) and an outer ring nozzle third tapered cavity (326).

6. The novel precooling spray system for cryogenic liquefied gas storage tanks according to claim 5 is characterized in that: The number of outer ring nozzles in each outer ring nozzle (32) is three, and the three outer ring nozzles are arranged at an angle of 45 degrees.

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