Leakage-proof pipeline of liquid oxygen sampling valve

Abstract

The utility model belongs to the technical field of air separation device sampling equipment, and relates to a liquid oxygen sampling valve leakproof pipeline which comprises an air cooling tower, an air suction pipeline is arranged on one side of the air cooling tower, the top of the air cooling tower is connected to a molecular sieve purifier, and the molecular sieve purifier is connected to a fractionating tower through an expansion pipeline. The fractionating tower comprises an upper fractionating tower body and a lower fractionating tower body, liquid oxygen is contained in the upper fractionating tower body, a main condensation evaporator is arranged in the upper fractionating tower body, a sampling pipeline is led out of one side of the upper fractionating tower body, a liquid oxygen sampling valve, a filter and a sampling secondary valve are sequentially arranged on the sampling pipeline, and the tail end of the sampling pipeline extends into a liquid oxygen liquid receiving tank. And a sampling beaker is arranged on one side of the liquid oxygen receiving tank. The filter is used for filtering particles, the double-valve design is adopted, online cleaning and replacement of the filter and the sampling valve can be achieved, unplanned shutdown of an air separation unit is avoided, and continuous production of a steel mill is kept.

Description

TECHNICAL FIELD

[0001] The utility model belongs to air separation device sampling equipment technical field, concretely relates to a kind of liquid oxygen sampling valve anti-leakage pipeline. BACKGROUND

[0002] Steel plant supporting air separation device is provided with fractionating column, steel plant supporting air separation device separates and prepares oxygen, nitrogen and other industrial gas medium using deep freezing method, supplies steelmaking, ironmaking production use. Among them, air separation device fractionating column main condensation evaporator is key position. Air is formed into liquid air in fractionating column after refrigeration, heat exchange. After the heat exchange of filler, liquid oxygen with the purity of 99.2% is accumulated in main condensation evaporator. In rectification heat exchange process, methane, acetylene and other hydrocarbons contained in air are accumulated in the liquid oxygen of main condensation evaporator. Once the concentration of carbon hydrogen compound in main condensation is too high to produce crystallization, it is extremely easy to cause combustion explosion under the combustion of liquid oxygen. Therefore, air separation device takes main cold liquid oxygen for chemical analysis every day.

[0003] In prior art, liquid oxygen sampling valve is worn in daily use, and the problem of leakage due to poor sealing is prone to occur. When replacing valve, air separation device needs to be stopped, and main cold liquid oxygen needs to be completely discharged, which will affect the continuous operation of air separation device and the production of steel plant. At the same time, due to the influence of use environment, liquid oxygen sampling valve has the problem of poor sealing. The fractionating column of air separation device is made of aluminum material, and aluminum chips generated during installation are easy to jam in the sealing surface of liquid oxygen sampling valve, resulting in sealing failure and liquid oxygen leakage. Therefore, a kind of liquid oxygen sampling valve anti-leakage pipeline is proposed. UTILITY MODEL CONTENTS

[0004] The utility model aims at providing a kind of liquid oxygen sampling valve anti-leakage pipeline, with liquid oxygen sampling valve anti-leakage function, solve the problem that the liquid oxygen sampling valve of prior art needs to replace valve, air separation device needs to be stopped and aluminum chip is easy to jam in the sealing surface of liquid oxygen sampling valve, resulting in sealing failure.

[0005] In order to achieve the above purpose, the utility model adopts the technical scheme that the utility model provides a kind of liquid oxygen sampling valve anti-leakage pipeline, including air cooling tower, the air cooling tower one side is provided with air suction pipeline, air cooling tower top is connected to molecular sieve purifier, molecular sieve purifier is connected to fractionating column by expansion pipeline, fractionating column includes fractionating column upper tower and fractionating column lower tower, fractionating column upper tower is equipped with liquid oxygen in the inside, fractionating column upper tower is provided with main condensation evaporator in the inside, fractionating column upper tower one side leads out sampling pipeline, sampling pipeline is sequentially provided with liquid oxygen sampling valve, filter and sampling secondary valve, sampling pipeline terminal end is inserted into liquid oxygen connection liquid tank, liquid oxygen connection liquid tank one side is provided with sampling beaker.

[0006] Preferably, the air suction pipeline is provided with air compressor.

[0007] As preferred, the expansion pipeline is provided with an expander.

[0008] As preferred, the expansion pipeline is connected to an upper column of a fractionating tower, and a connecting pipeline is led out from the expansion pipeline and connected to a lower column of the fractionating tower.

[0009] As preferred, upper and lower flanges are arranged at the front and back ends of the filter.

[0010] As preferred, the filter is arranged between a liquid oxygen sampling valve and a sampling secondary valve, the filter is made of stainless steel, and the filter screen is of a 150-200 mesh type.

[0011] Compared with the prior art, the utility model has the advantages and positive effects that,

[0012] 1. The utility model utilizes the filter to filter particles, adopts a double valve design, can realize online cleaning and replacement of the filter and the sampling valve, avoids unplanned shutdown of the air separation unit, and maintains continuous production of the steel plant.

[0013] 2. The utility model has the liquid oxygen sampling valve anti-leakage function, solves the problem that the air separation device needs to be stopped and aluminum scraps are easily jammed at the sealing surface of the liquid oxygen sampling valve to cause sealing failure when the valve of the liquid oxygen sampling valve is replaced in the prior art. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical scheme of the embodiments of the utility model, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are some embodiments of the utility model, and other drawings can also be obtained by those skilled in the art without creative labor.

[0015] Figure 1 It is a structure diagram of a liquid oxygen sampling valve anti-leakage pipeline.

[0016] In the above figure, 1 is an air suction pipeline, 2 is an air compressor, 3 is an air cooling tower, 4 is a molecular sieve purifier, 5 is an expander, 6 is an upper column of a fractionating tower, 7 is a main condenser evaporator, 8 is liquid oxygen, 9 is a lower column of the fractionating tower, 10 is a liquid oxygen sampling valve, 11 is a sampling beaker, 12 is a liquid oxygen receiving tank, 13 is an upper flange, 14 is a filter, 15 is a lower flange, and 16 is a sampling secondary valve. DETAILED DESCRIPTION

[0017] In order to more clearly illustrate the technical scheme of the embodiments of the utility model, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are some embodiments of the utility model, and other drawings can also be obtained by those skilled in the art without creative labor.

[0018] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed in the following specification.

[0019] Example 1, such as Figure 1 As shown, a leak-proof pipeline for a liquid oxygen sampling valve includes an air-cooled tower 3. An air intake pipe 1 is installed on one side of the air-cooled tower 3. The air intake pipe 1 is used to obtain external air as the feed gas for the cooling and separation processes in the air separation unit, ensuring a stable supply of feed gas and enabling continuous system operation. The air-cooled tower 3 cools the air and simultaneously exchanges heat with the surrounding environment to lower its temperature, which helps improve the efficiency of subsequent fractionation towers.

[0020] The top of the air-cooled tower 3 is connected to the molecular sieve purifier 4, which removes moisture and carbon dioxide from the air, ensuring the purity of the gas entering the fractionation tower and improving the separation effect and the quality of the final product. The molecular sieve purifier 4 is connected to the fractionation tower via an expansion pipe. The fractionation tower includes an upper fractionation tower 6 and a lower fractionation tower 9. The upper fractionation tower 6 contains liquid oxygen 8 and is equipped with a main condenser-evaporator 7, which performs condensation and evaporation, separating different gas components and collecting high-purity liquid oxygen 8. The upper fractionation tower 6 is used to fractionate liquid air, separating gases such as oxygen and nitrogen. The liquid oxygen 8 inside the tower is purified to high purity through fractionation for industrial applications such as steelmaking. The lower fractionation tower 9, together with the upper fractionation tower 6, constitutes the fractionation system, mainly used to collect the unseparated heavy gas components and continue the fractionation process. The main condenser-evaporator 7 is the link between the upper column 6 and the lower column 9 of the fractionation column, which liquefies the air and allows liquid oxygen 8 to accumulate in the main condenser-evaporator 7.

[0021] A sampling pipeline extends from one side of the upper column 6 of the fractionation tower. The sampling pipeline is sequentially equipped with a liquid oxygen sampling valve 10, a filter 14, and a secondary sampling valve 16. The sampling pipeline is used to sample liquid oxygen 8 for testing, aiming to monitor the quality and safety of the liquid oxygen 8. The liquid oxygen sampling valve 10 controls the opening and closing of the sampling pipeline, controlling the flow rate of liquid oxygen 8. The secondary sampling valve 16 is used to further control and isolate the flow of liquid oxygen 8 in the sampling pipeline to reduce the risk of leakage. The filter 14 is used to filter impurities in the liquid oxygen 8, preventing particulate matter from affecting the sealing performance of the secondary sampling valve 16, thereby avoiding leakage.

[0022] The sampling pipe end extends into the liquid oxygen contact tank 12, which is used to temporarily store the sampled liquid oxygen 8, ensuring that the sampling process does not affect the operation of the main condenser evaporator 7. The liquid oxygen contact tank 12 is provided with a sampling beaker 11 on one side, which receives the liquid oxygen 8 sample for laboratory analysis. The frequency of liquid oxygen 8 sampling and analysis is once a day, and the main analysis indicators are methane, acetylene, etc. When sampling, a sampling beaker 11 with a handle is required.

[0023] Now let's talk about the specific design of the above key components:

[0024] The air suction pipe 1 is provided with an air compressor 2. The air compressor 2 compresses the air to increase its pressure, adapting to the subsequent deep freezing separation process. In addition, the temperature of the compressed air rises and needs to be cooled to reach a suitable temperature for fractionation. The air compressor 2 consumes electrical energy to suck in the raw air and give it kinetic energy. The outlet temperature of the air compressor 2 is about 80°C, and after entering the air cooling tower 3, the temperature is reduced to 14°C.

[0025] The expansion pipeline is provided with an expander 5. The expander 5 rapidly cools the gas through the expansion process to form liquid air suitable for separation, which can help achieve gas expansion cooling and improve the efficiency of the entire separation process.

[0026] The expansion pipeline is connected to the upper tower 6 of the fractionation column, and a connecting pipeline is drawn from the expansion pipeline to the lower tower 9 of the fractionation column. One route of expanded air in the expansion pipeline enters the upper tower 6 of the fractionation column for rectification, and the other route of air enters the lower tower 9 of the fractionation column to form oxygen-rich liquid air.

[0027] The filter 14 is provided with an upper flange 13 and a lower flange 15 at both ends. The upper flange 13 and the lower flange 15 are used to connect the filter 14 to the sampling pipe to achieve sealed connection.

[0028] The filter 14 is arranged between the liquid oxygen sampling valve 10 and the sampling secondary valve 16. The filter 14 is made of stainless steel, which meets the requirements of use in a low-temperature environment of liquid oxygen 8. The filter 14 has a filter mesh size of 150-200 mesh, which can effectively filter out small aluminum chips.

[0029] Example 2, the liquid oxygen sampling valve leak-proof pipeline shown in example 1 has the following design points:

[0030] (1) Double valve design: the liquid oxygen sampling valve 10 is normally open, and the sampling secondary valve 16 is operated during daily sampling. When sampling, open the sampling secondary valve 16, and close it after sampling is completed.

[0031] (2) On-line replacement of liquid oxygen sampling valve 10: when the sampling secondary valve 16 is not tightly closed and leakage occurs, temporarily close the liquid oxygen sampling valve 10. Open the sampling secondary valve 16 to discharge the liquid oxygen 8 remaining in the pipeline into the liquid oxygen receiving tank 12, remove the lower flange 15 of the filter 14, and take the sampling secondary valve 16 offline and replace it with a new valve. After the new valve is online, switch the valve. Open the liquid oxygen sampling valve 10 and keep it open. By operating the sampling secondary valve 16, the daily liquid oxygen 8 sampling operation is carried out.

[0032] (3) On-line cleaning of filter 14: in the daily sampling operation, the filter 14 collects the aluminum scraps flowing into the fractionating column with the liquid oxygen 8. As the aluminum scraps are gradually collected, the discharge flow of the liquid oxygen 8 gradually decreases during the sampling operation, and the filter 14 needs to be cleaned at this time. Before cleaning, the discharge pipeline remains liquid oxygen 8. First, close the liquid oxygen sampling valve 10 and open the lower sampling secondary valve 16 to discharge the remaining liquid oxygen 8 into the liquid oxygen receiving tank 12; second, remove the filter 14 from the pipeline system by disassembling the upper flange 13 and the lower flange 15, and take it offline for cleaning; third, connect the upper flange 13 and the lower flange 15 to bring the filter 14 online. Then open the liquid oxygen sampling valve 10 and close the sampling secondary valve 16.

[0033] The standard parts used in the utility model can be purchased from the market, and the special-shaped parts can be ordered according to the description and the drawings, the specific connection mode of each part adopts the conventional means such as bolts, rivets and welding in the prior art, the machinery, parts and equipment adopt the conventional types in the prior art, and the circuit connection adopts the conventional connection mode in the prior art, which will not be described in detail here, and the contents not described in detail in the specification belong to the prior art known to those skilled in the art.

[0034] The above is only a preferred embodiment of the utility model, and is not intended to limit other forms of the utility model. Any skilled person in the art can modify or retrofit the above disclosed technical content to equivalent embodiments applied to other fields, but any simple modification, equivalent change and retrofit made according to the technical essence of the utility model to the above embodiments still belongs to the protection scope of the technical scheme of the utility model.

Claims

1. A LOX sampling valve leak-proof line, characterized in that, The air cooling tower is provided with an air suction pipeline on one side, the top of the air cooling tower is connected to a molecular sieve purifier, the molecular sieve purifier is connected to a fractionating tower through an expansion pipeline, the fractionating tower comprises an upper fractionating tower and a lower fractionating tower, the upper fractionating tower is internally provided with liquid oxygen, the upper fractionating tower is internally provided with a main condenser evaporator, a sampling pipeline is led out from one side of the upper fractionating tower, the sampling pipeline is sequentially provided with a liquid oxygen sampling valve, a filter and a sampling secondary valve, the sampling pipeline is inserted into a liquid oxygen receiving tank at the end, and a sampling beaker is arranged on one side of the liquid oxygen receiving tank.

2. The LOX sampling valve leak-proof line of claim 1, wherein, An air compressor is arranged on the air suction pipeline.

3. The LOX sampling valve leak-proof line of claim 1, wherein, An expander is arranged on the expansion pipeline.

4. The LOX sampling valve leak-proof line of claim 1, wherein, The expansion pipeline is connected to the upper fractionating tower, and a connecting pipeline is led out from the expansion pipeline and connected to the lower fractionating tower.

5. The LOX sampling valve leak-proof line of claim 1, wherein, The filter is provided with upper and lower flanges at the front and rear ends.

6. The LOX sampling valve leak-proof line of claim 1, wherein, The filter is arranged between the liquid oxygen sampling valve and the sampling secondary valve, is made of stainless steel, and has a filter screen with a mesh size of 150-200.

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