System for extracting helium from BOG (Boil Off Gas)

Abstract

The utility model discloses a system for extracting helium from BOG (Boil Off Gas). The system comprises a cooler, an adsorption device and a product gas buffer tank which are sequentially connected to the rear end of a feed gas conveying pipeline, the adsorption device comprises two adsorption columns and heating units in one-to-one correspondence with the adsorption columns, the adsorption columns have an adsorption state and a desorption state, the heating units are used for providing heat for the corresponding adsorption columns in the desorption state, and the two adsorption columns alternately perform the adsorption state and the desorption state; the gas outlet end of the product gas buffer tank is respectively communicated with subsequent treatment equipment and a cooler; the cooler is used for alternately cooling the raw material gas and the product gas generated after the adsorption treatment of the adsorption column, and after the cooler cools the raw material gas, the cooled raw material gas is conveyed to the adsorption column in an adsorption state; and after the cooler cools the product gas, the cooled product gas is conveyed to the adsorption column in the desorption state. The cooling device is good in cooling effect and high in cooling efficiency. And the operation efficiency and stability of the system are high.

Description

Technical Field

[0001] The utility model relates to the technical field of gas adsorption and separation, and in particular to a BOG gas helium extraction system. Background Art

[0002] Helium is widely used in aerospace, large scientific engineering, medical nuclear magnetic resonance, and high-end equipment manufacturing fields such as semiconductors and optical fibers due to its unique physical and chemical properties such as low density, low boiling point, excellent thermal conductivity and chemical stability. However, due to the extremely low helium content in natural gas, its extraction cost is extremely high, and currently it mainly relies on concentrated BOG gas to extract helium. In response to the problem of extracting helium from BOG, a variety of feasible technical solutions have emerged at home and abroad, some of which have been industrialized. These solutions include cryogenics, liquefaction, pressure swing adsorption, membrane separation, and their combination. In particular, pressure swing adsorption is currently widely used due to its advantages such as low energy consumption, high efficiency and strong environmental protection.

[0003] In the pressure swing adsorption method, the adsorption column is a key component. The concentrated BOG gas passes through the adsorption column filled with adsorbent, and the adsorbent adsorbs and desorbs the gas by cyclically changing the pressure, thereby separating the target gas. The heat released during the adsorption process causes the temperature of the adsorption column to rise, thereby affecting the adsorption effect. Therefore, a cold source is required to synchronously cool the adsorption column to maintain its normal adsorption capacity. As the use time increases, the adsorbent will gradually become saturated, and the adsorption column needs to be desorbed to release the adsorbed gas to restore its adsorption capacity. The desorption process requires a heat source to heat the adsorption column to prompt the adsorbent to release the adsorbed gas.

[0004] In current technology, the same heat transfer oil is usually used to achieve both cooling and heating of the adsorption column. However, due to the limited high and low temperature resistance of the same heat transfer oil, while meeting its high temperature resistance to achieve the heating effect, it leads to poor low temperature resistance, poor cooling effect, and low cooling efficiency, thus affecting production efficiency. Utility Model Content

[0005] The utility model aims to provide a BOG gas helium extraction system, which cools the raw gas by a cooler instead of cooling the adsorption column by heat transfer oil, so as to solve the problem in the prior art that the heat transfer oil has limited low temperature resistance while being resistant to high temperatures, resulting in poor cooling effect on the adsorption column and low cooling efficiency.

[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0007] A BOG gas helium extraction system comprises a cooler, an adsorption device and a product gas buffer tank which are sequentially connected to the rear end of a raw gas delivery pipeline;

[0008] The adsorption device comprises two adsorption columns and heating units corresponding to the adsorption columns one by one, the adsorption columns have an adsorption state and a desorption state, the heating unit is used to provide heat to the corresponding adsorption column in the desorption state, and the two adsorption columns rotate to perform the adsorption state and the desorption state;

[0009] The gas outlet end of the product gas buffer tank is connected to the subsequent processing equipment and the cooler respectively;

[0010] The cooler is used to alternately cool the raw gas and the product gas generated after adsorption treatment by the adsorption column;

[0011] After the cooler cools the raw gas, the cooled raw gas is transported to the adsorption column in an adsorption state;

[0012] After the cooler cools the product gas, the cooled product gas is transported to the adsorption column in the desorption state.

[0013] In some embodiments, the air inlet end of the cooler is connected to the raw gas delivery pipeline through a feed pipe, and a first ball valve is provided between the feed pipe and the raw gas delivery pipeline.

[0014] In some embodiments, the gas outlet end of the cooler is connected to the gas inlet ends of the two adsorption columns through a raw gas inlet pipeline, and the raw gas inlet pipeline includes an inlet main pipe and two inlet branches respectively connected to the inlet main pipe;

[0015] The air intake main pipe is connected to the air outlet end of the cooler, and the two air intake branch pipes are connected to the air intake ends of the two adsorption columns in a one-to-one manner. A second ball valve is arranged on the air intake main pipe, and a first pneumatic valve is arranged on the air intake branch pipe.

[0016] In some embodiments, the gas outlet ends of the two adsorption columns are connected to the gas inlet end of the product gas buffer tank through a product gas outlet pipeline, and the product gas outlet pipeline includes a gas outlet main pipe and two gas outlet branches respectively connected to the gas outlet main pipe;

[0017] The gas outlet main pipe is connected to the gas inlet end of the product gas buffer tank, and the two gas outlet branch pipes are connected to the gas outlet ends of the two adsorption columns in a one-to-one manner. A third ball valve is provided on the gas outlet main pipe, and a second pneumatic valve is provided on the gas outlet branch pipe.

[0018] In some embodiments, the gas outlet of the product gas buffer tank is connected to the subsequent processing equipment through a discharge pipe, and is connected to the gas inlet of the cooler through a reflux pipeline;

[0019] The reflux pipe is provided with a fourth ball valve and a flow regulating valve, and the discharge pipe is provided with a fifth ball valve and a pressure regulating valve.

[0020] In some embodiments, a reflux air intake pipeline is further connected between the air outlet end of the cooler and the air inlet ends of the two adsorption columns, and the reflux air intake pipeline includes a reflux air intake main pipe and two reflux air intake branch pipes respectively connected to the reflux air intake main pipe;

[0021] The return air intake main pipe is connected to the air outlet end of the cooler, and the two return air intake branch pipes are connected to the two air intake branch pipes in a one-to-one manner. A third pneumatic valve is arranged on the return air intake branch pipe.

[0022] In some embodiments, a reflux outlet pipeline is provided between the outlet ends of the two adsorption columns and the discharge pipe, and the reflux outlet pipeline includes a reflux outlet main pipe and two reflux outlet branch pipes respectively connected to the reflux outlet main pipe;

[0023] The reflux outlet main pipe is connected to the discharge pipe, and the fifth ball valve and the pressure regulating valve are located between the outlet end of the product gas buffer tank and the reflux outlet main pipe;

[0024] The two return air outlet branch pipes are connected to the two air outlet branch pipes in a one-to-one manner, and a fourth pneumatic valve is provided on the return air outlet branch pipe.

[0025] In some embodiments, a concentration detection element is disposed on the reflux outlet main pipe, and the concentration detection element is used to detect the concentration of the product gas in the reflux outlet main pipe.

[0026] In some embodiments, the heating unit is an electric heating device or a heat transfer oil device.

[0027] Due to the application of the above technical solution, the beneficial effects of the present application compared with the prior art are:

[0028] The present application provides a BOG gas helium extraction system, which cools the raw gas by setting a cooler to directly extract the heat of the raw gas, replacing the traditional method of cooling the adsorption column with heat transfer oil. It is not limited by the high and low temperature resistance of the heat transfer oil, and improves the cooling effect and efficiency.

[0029] At the same time, the two adsorption columns are used in rotation to achieve continuous adsorption and desorption. When one adsorption column is in the adsorption state, the other can be in the desorption state, thereby achieving continuous production and improving the operating efficiency and stability of the system.

[0030] In addition, the product gas generated after adsorption treatment by the adsorption column is transported to the cooler for further cooling, and then output through the adsorption column in the desorption state to take away the excess heat provided to the adsorption column by the heating unit during the desorption process. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 It is a structural schematic diagram of a BOG gas helium extraction system shown in an embodiment of the utility model.

[0033] Description of Reference Numerals

[0034] 1-Cooler; 2-Adsorption column; 3-Product gas buffer tank; 4-Feed pipe; 5-First ball valve; 6-Raw gas inlet pipeline; 61-Inlet main pipe; 62-Inlet branch pipe; 63-Second ball valve; 64-First pneumatic valve; 7-Product gas outlet pipeline; 71-Outlet main pipe; 72-Outlet branch pipe; 73-Third ball valve; 74-Second pneumatic valve; 8-Return pipeline; 9-Fourth ball valve; 10-Flow regulating valve; 20-Fifth ball valve; 30-Pressure regulating valve; 40-Return inlet pipeline; 401-Return inlet main pipe; 402-Return inlet branch pipe; 403-Third pneumatic valve; 50-Return outlet pipeline; 501-Return outlet main pipe; 502-Return outlet branch pipe; 503-Fourth pneumatic valve; 100-Subsequent processing equipment. DETAILED DESCRIPTION

[0035] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0036] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0037] In this application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the utility model and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0038] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those skilled in the art, the specific meanings of these terms in this utility model can be understood according to specific circumstances.

[0039] In addition, the terms "installed", "set", "provided with", "connected", "connected", and "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0040] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0041] See also Figure 1 The embodiment of the present application provides a BOG gas helium extraction system, which includes a cooler 1, an adsorption device and a product gas buffer tank 3 which are sequentially connected to the rear end of a raw gas delivery pipeline.

[0042] In some embodiments, the air inlet end of the cooler 1 is connected to the raw gas delivery pipeline through the feed pipe 4, and a first ball valve 5 is provided between the feed pipe 4 and the raw gas delivery pipeline.

[0043] The adsorption device includes two adsorption columns 2 and heating units (not shown) corresponding to the adsorption columns 2. The adsorption columns 2 have an adsorption state and a desorption state. The heating unit is used to provide heat to the corresponding adsorption column 2 in the desorption state. The two adsorption columns 2 rotate between the adsorption state and the desorption state.

[0044] In some embodiments, the gas outlet of the cooler 1 is connected to the gas inlet ends of the two adsorption columns 2 through the raw gas inlet pipeline 6, and the raw gas inlet pipeline 6 includes an inlet main pipe 61 and two inlet branch pipes 62 respectively connected to the inlet main pipe 61. The inlet main pipe 61 is connected to the gas outlet of the cooler 1, and the two inlet branch pipes 62 are connected to the gas inlet ends of the two adsorption columns 2 in a one-to-one manner. The inlet main pipe 61 is provided with a second ball valve 63, and the inlet branch pipe 62 is provided with a first pneumatic valve 64.

[0045] In some embodiments, the heating unit is an electric heating device or a heat transfer oil device. It is a conventional structure and will not be described in detail here.

[0046] The gas outlet end of the product gas buffer tank 3 is connected to the subsequent processing equipment 100 and the cooler 1 respectively.

[0047] In some embodiments, the gas outlet ends of the two adsorption columns 2 are connected to the gas inlet end of the product gas buffer tank 3 through the product gas outlet pipeline 7, and the product gas outlet pipeline 7 includes a gas outlet main pipe 71 and two gas outlet branch pipes 72 respectively connected to the gas outlet main pipe 71. The gas outlet main pipe 71 is connected to the gas inlet end of the product gas buffer tank 3, and the two gas outlet branch pipes 72 are connected to the gas outlet ends of the two adsorption columns 2 in a one-to-one manner. The gas outlet main pipe 71 is provided with a third ball valve 73, and the gas outlet branch pipe 72 is provided with a second pneumatic valve 74.

[0048] In some embodiments, the gas outlet of the product gas buffer tank 3 is connected to the subsequent processing equipment 100 through the discharge pipe, and is connected to the gas inlet of the cooler 1 through the reflux line 8. A fourth ball valve 9 and a flow regulating valve 10 are provided on the reflux pipe, and a fifth ball valve 20 and a pressure regulating valve 30 are provided on the discharge pipe.

[0049] In some embodiments, a reflux air intake pipeline 40 is also provided between the air outlet of the cooler 1 and the air inlet of the two adsorption columns 2, and the reflux air intake pipeline 40 includes a reflux air intake main pipe 401 and two reflux air intake branch pipes 402 respectively connected to the reflux air intake main pipe 401. The reflux air intake main pipe 401 is connected to the air outlet of the cooler 1, and the two reflux air intake branch pipes 402 are connected to the two air intake branch pipes 62 in a one-to-one manner, and a third pneumatic valve 403 is provided on the reflux air intake branch pipe 402.

[0050] In some embodiments, a reflux outlet pipeline 50 is provided between the outlet ends of the two adsorption columns 2 and the discharge pipe, and the reflux outlet pipeline 50 includes a reflux outlet main pipe 501 and two reflux outlet branch pipes 502 respectively connected to the reflux outlet main pipe 501. The reflux outlet main pipe 501 is connected to the discharge pipe, and the fifth ball valve 20 and the pressure regulating valve 30 are located between the outlet end of the product gas buffer tank 3 and the reflux outlet main pipe 501. The two reflux outlet branch pipes 502 are connected to the two outlet branch pipes 72 in a one-to-one manner, and a fourth pneumatic valve 503 is provided on the reflux outlet branch pipe 502.

[0051] In some embodiments, a concentration detection element (not shown) is disposed on the reflux outlet main pipe 501 , and the concentration detection element is used to detect the concentration of the product gas in the reflux outlet main pipe 501 .

[0052] When in use, the cooler 1 is used to alternately cool the raw gas and the product gas generated after adsorption treatment by the adsorption column 2. After the cooler 1 cools the raw gas, the cooled raw gas is transported to the adsorption column 2 in the adsorption state. After the cooler 1 cools the product gas, the cooled product gas is transported to the adsorption column 2 in the desorption state.

[0053] Due to the application of the above technical solution, the beneficial effects of the present application compared with the prior art are:

[0054] The present application provides a BOG gas helium extraction system, which cools the raw gas by setting a cooler to directly extract the heat of the raw gas, replacing the traditional method of cooling the adsorption column with heat transfer oil. It is not limited by the high and low temperature resistance of the heat transfer oil, and improves the cooling effect and efficiency.

[0055] At the same time, the two adsorption columns are used in rotation to achieve continuous adsorption and desorption. When one adsorption column is in the adsorption state, the other can be in the desorption state, thereby achieving continuous production and improving the operating efficiency and stability of the system.

[0056] In addition, the product gas generated after adsorption treatment by the adsorption column is transported to the cooler for further cooling, and then output through the adsorption column in the desorption state to take away the excess heat provided to the adsorption column by the heating unit during the desorption process.

[0057] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A BOG gas helium extraction system, characterized in that: It includes a cooler, an adsorption device and a product gas buffer tank which are sequentially connected to the rear end of the raw gas delivery pipeline; The adsorption device comprises two adsorption columns and heating units corresponding to the adsorption columns one by one, the adsorption columns have an adsorption state and a desorption state, the heating unit is used to provide heat to the corresponding adsorption column in the desorption state, and the two adsorption columns rotate to perform the adsorption state and the desorption state; The gas outlet end of the product gas buffer tank is connected to the subsequent processing equipment and the cooler respectively; The cooler is used to alternately cool the raw gas and the product gas generated after adsorption treatment by the adsorption column; After the cooler cools the raw gas, the cooled raw gas is transported to the adsorption column in an adsorption state; After the cooler cools the product gas, the cooled product gas is transported to the adsorption column in the desorption state.

2. A BOG gas helium extraction system as claimed in claim 1, characterized in that: The air inlet end of the cooler is connected to the raw gas delivery pipeline through a feed pipe, and a first ball valve is provided between the feed pipe and the raw gas delivery pipeline.

3. A BOG gas helium extraction system as claimed in claim 1, characterized in that: The gas outlet end of the cooler is connected to the gas inlet ends of the two adsorption columns through a raw gas inlet pipeline, and the raw gas inlet pipeline includes an inlet main pipe and two inlet branches respectively connected to the inlet main pipe; The air intake main pipe is connected to the air outlet end of the cooler, and the two air intake branch pipes are connected to the air intake ends of the two adsorption columns in a one-to-one manner. A second ball valve is arranged on the air intake main pipe, and a first pneumatic valve is arranged on the air intake branch pipe.

4. A BOG gas helium extraction system as claimed in claim 3, characterized in that: The gas outlet ends of the two adsorption columns are connected to the gas inlet end of the product gas buffer tank through a product gas outlet pipeline, and the product gas outlet pipeline includes a gas outlet main pipe and two gas outlet branches respectively connected to the gas outlet main pipe; The gas outlet main pipe is connected to the gas inlet end of the product gas buffer tank, and the two gas outlet branch pipes are connected to the gas outlet ends of the two adsorption columns in a one-to-one manner. A third ball valve is provided on the gas outlet main pipe, and a second pneumatic valve is provided on the gas outlet branch pipe.

5. A BOG gas helium extraction system as claimed in claim 4, characterized in that: The gas outlet end of the product gas buffer tank is connected to the subsequent processing equipment through a discharge pipe, and is connected to the gas inlet end of the cooler through a reflux pipeline; The reflux pipe is provided with a fourth ball valve and a flow regulating valve, and the discharge pipe is provided with a fifth ball valve and a pressure regulating valve.

6. A BOG gas helium extraction system as claimed in claim 5, characterized in that: A reflux air intake pipeline is also provided between the air outlet end of the cooler and the air inlet ends of the two adsorption columns, and the reflux air intake pipeline includes a reflux air intake main pipe and two reflux air intake branch pipes respectively connected to the reflux air intake main pipe; The return air intake main pipe is connected to the air outlet end of the cooler, and the two return air intake branch pipes are connected to the two air intake branch pipes in a one-to-one manner. A third pneumatic valve is arranged on the return air intake branch pipe.

7. A BOG gas helium extraction system as claimed in claim 6, characterized in that: A reflux outlet pipeline is provided between the outlet ends of the two adsorption columns and the discharge pipe, and the reflux outlet pipeline includes a reflux outlet main pipe and two reflux outlet branch pipes respectively connected to the reflux outlet main pipe; The reflux outlet main pipe is connected to the discharge pipe, and the fifth ball valve and the pressure regulating valve are located between the outlet end of the product gas buffer tank and the reflux outlet main pipe; The two return air outlet branch pipes are connected to the two air outlet branch pipes in a one-to-one manner, and a fourth pneumatic valve is provided on the return air outlet branch pipe.

8. A BOG gas helium extraction system as claimed in claim 7, characterized in that: The reflux outlet main pipe is provided with a concentration detection component, and the concentration detection component is used to detect the concentration of the product gas in the reflux outlet main pipe.

9. A BOG gas helium extraction system as claimed in claim 1, characterized in that: The heating unit is an electric heating device or a heat transfer oil device.

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