Device for separating air, oxygen and nitrogen based on krypton-xenon refined liquid

Abstract

The utility model discloses an air-oxygen-nitrogen separation device based on krypton-xenon refined liquid, and relates to the technical field of liquid air energy storage. The device comprises a liquid air storage tank, a liquid pump, a rectifying tower, a subcooler, a main heat exchanger, an oxygen heat exchanger, a liquid nitrogen storage tank, a liquid oxygen storage tank, a nitrogen circulating compressor and the like. Wherein the rectifying tower completes separation of oxygen and nitrogen in liquid air through structured packing and a condensation evaporator; and the oxygen and the nitrogen are respectively output to a liquid oxygen storage tank, a liquid nitrogen storage tank or a low-pressure pipe network after being treated by processes such as multi-stage heat exchange, throttling and cyclic compression. The device makes full use of thermodynamic characteristics of liquid air, oxygen and nitrogen separation is directly carried out, external cold supplement is not needed, energy consumption is remarkably reduced, and economic benefits are improved. The combined krypton-xenon refining process solves the problems of cold source demand and nitrogen recycling, realizes zero emission of waste gas, sewage and dust, and is excellent in environmental protection performance. And the device is short in process, low in equipment requirement, high in operation reliability and suitable for industrial application, and the investment and maintenance cost is reduced.

Description

TECHNICAL FIELD

[0001] The utility model belongs to liquid air energy storage technical field relates to a device based on krypton xenon refined liquid air oxygen nitrogen separation. BACKGROUND

[0002] Liquid air energy storage technology is a new energy storage technology, its basic principle is through air liquefying device cooling air to extremely low temperature becomes liquid form, in order to store and use.This technology has wide application prospect, is a new technology that can solve our energy storage and conversion problem.

[0003] At present, liquid air energy storage is mainly applied to power generation and cold storage, but there is no corresponding precedent for directly separating low-temperature oxygen and nitrogen liquid products, and this field is still blank;Liquid air power generation and cold storage for the reuse of liquid air, the efficiency is relatively low, the potential of liquid air itself is not fully developed, if the liquid air energy storage technology is converted into liquid air and directly separated, its thermodynamic properties will be fully utilized, and the efficiency will be higher, compared with traditional full-liquid air separation, the production and operation cost will be greatly reduced.

[0004] Overall, liquid air oxygen nitrogen separation technology has wide application prospect, and is expected to provide a better choice for solving the energy storage and conversion problem. CONTENT OF THE UTILITY MODEL

[0005] Therefore, the utility model aims at solving the above problems, and provides a device based on krypton xenon refined liquid air oxygen nitrogen separation.

[0006] To achieve the above object, the utility model provides the following technical scheme.

[0007] A device based on krypton xenon refined liquid air oxygen nitrogen separation, including liquid air storage tank, liquid pump, rectifying tower, subcooler, main heat exchanger, oxygen heat exchanger, liquid nitrogen storage tank, liquid oxygen storage tank, nitrogen circulating compressor;

[0008] The rectification tower comprises a tower body, structured packing arranged in the tower body, and a condensation evaporator integrated in the lower part of the tower body; six inlets and outlets are arranged on the tower body, which are respectively a liquid nitrogen inlet, a liquid air inlet, a liquid oxygen outlet, an oxygen outlet, a nitrogen outlet, and a waste nitrogen outlet; three groups of inlets and outlets are arranged on the subcooler, which are respectively a first inlet of the subcooler, a first outlet of the subcooler, a second inlet of the subcooler, a second outlet of the subcooler, a third inlet of the subcooler, and a third outlet of the subcooler; four groups of inlets and outlets are arranged on the main heat exchanger, which are respectively a first inlet of the main heat exchanger, a first outlet of the main heat exchanger, a second inlet of the main heat exchanger, a second outlet of the main heat exchanger, a third inlet of the main heat exchanger, a third outlet of the main heat exchanger, a fourth inlet of the main heat exchanger, and a fourth outlet of the main heat exchanger; two groups of inlets and outlets are arranged on the oxygen heat exchanger, which are respectively a first inlet of the oxygen heat exchanger, a first outlet of the oxygen heat exchanger, a second inlet of the oxygen heat exchanger, and a second outlet of the oxygen heat exchanger.

[0009] The liquid air storage tank is communicated with the liquid air inlet through a liquid pump, the nitrogen outlet is communicated with the first inlet of the subcooler, the first outlet of the subcooler is communicated with the first inlet of the main heat exchanger; the first outlet of the main heat exchanger is communicated with the inlet of the nitrogen circulating compressor, the outlet of the nitrogen circulating compressor is divided into two paths, one path goes to the instrument gas, the warming gas, and the purge gas header, and the other path is communicated with the third inlet of the main heat exchanger; the third outlet of the main heat exchanger is communicated with the inlet of the condensation evaporator, the outlet of the condensation evaporator is communicated with the second inlet of the subcooler, the second outlet of the subcooler is divided into two paths, one path is communicated with the liquid nitrogen inlet through a first throttling valve, and the other path is divided into three paths again, the first path is connected to the liquid nitrogen storage tank through a second throttling valve, the second path is connected to the second inlet of the oxygen heat exchanger through a third throttling valve, and the third path goes to the krypton-xenon refining device as a cold source; the second outlet of the oxygen heat exchanger is communicated with the inlet of the nitrogen circulating compressor, the oxygen outlet is communicated with the second inlet of the main heat exchanger, and the second outlet of the main heat exchanger is connected to the low-pressure oxygen pipe network or is connected to the atmosphere for venting; the waste nitrogen outlet is communicated with the third inlet of the subcooler, the third outlet of the subcooler is communicated with the fourth inlet of the main heat exchanger, and the fourth outlet of the main heat exchanger is connected to the atmosphere for venting.

[0010] The first inlet of the oxygen heat exchanger is connected to oxygen from krypton-xenon refining, and the first outlet of the oxygen heat exchanger is connected to the liquid oxygen storage tank after being collected through a fourth throttling valve and the liquid oxygen outlet.

[0011] Preferably, the rectification tower is a structured packing reboiling absorption tower.

[0012] Preferably, the liquid oxygen storage tank and the liquid nitrogen storage tank are both normal-pressure low-temperature liquid storage tanks.

[0013] Preferably, the liquid air storage tank is a normal-pressure low-temperature liquid storage tank.

[0014] Preferably, the liquid pump is a centrifugal low-temperature liquid pump.

[0015] Preferably, the condensing evaporator is a full-immersion liquid oxygen finned condensing evaporator.

[0016] Preferably, the nitrogen circulation compressor is a centrifugal nitrogen circulation compressor.

[0017] Preferably, the main heat exchanger, the supercooler and the oxygen heat exchanger are all finned heat exchangers.

[0018] The beneficial effects of the present application are as follows:

[0019] 1. The present application uses liquid air as raw material, directly separates oxygen and nitrogen, and obtains liquid oxygen and liquid nitrogen products, which is different from the traditional full-liquid air separation using air as raw material.

[0020] 2. In the linkage process with krypton and xenon refining, the problem of using liquid nitrogen as a cold source for krypton and xenon refining and then recycling after gasification is solved, and at the same time, liquid air obtained by liquid air energy storage can be directly separated into required liquid oxygen and nitrogen products, avoiding waste of a large amount of nitrogen and consumption of energy.

[0021] 3. The production process of the present application for separating oxygen and nitrogen using liquid air does not emit waste gas, wastewater and dust.

[0022] 4. The present application uses liquid air as raw material, and the oxygen and nitrogen separation process is short, omitting the pre-cooling system and the purification system, requiring less equipment, reducing equipment failure points, increasing the reliability of equipment operation, saving the overall investment and equipment maintenance cost.

[0023] 5. The present application uses nitrogen separated by liquid air as a heat source for recycling, without the need for external supplement, reducing production cost.

[0024] Other advantages, objects and features of the present application will be described in the following description, and to some extent, will be apparent to those skilled in the art based on the study of the following, or can be taught from the practice of the present application. The objects and other advantages of the present application can be achieved and obtained by the following description. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application will be described in detail below with reference to the drawings, in which:

[0026] Figure 1 The schematic diagram of the device for separating oxygen and nitrogen based on krypton and xenon refining in the present application.

[0027] Reference: 1 - rectifying column; 2 - subcooler; 3 - main heat exchanger; 4 - liquid air tank; 5 - liquid pump; 6 - nitrogen circulation compressor; 7 - liquid oxygen tank; 8 - liquid nitrogen tank; 9 - oxygen heat exchanger; 11 - liquid nitrogen inlet; 12 - liquid air inlet; 13 - condensing evaporator inlet; 14 - liquid oxygen outlet; 15 - condensing evaporator outlet; 16 - oxygen outlet; 17 - dirty nitrogen gas outlet; 18 - nitrogen gas outlet; 24 - subcooler first inlet; 22 - subcooler second inlet; 26 - subcooler third inlet; 21 - subcooler first outlet; 25 - subcooler second outlet; 23 - subcooler third outlet; 31 - main heat exchanger first inlet; 32 - main heat exchanger second inlet; 33 - main heat exchanger third outlet; 34 - main heat exchanger fourth inlet; 35 - main heat exchanger first outlet; 36 - main heat exchanger second outlet; 37 - main heat exchanger third inlet; 38 - main heat exchanger fourth outlet; 91 - oxygen heat exchanger first outlet; 92 - oxygen heat exchanger second inlet; 93 - oxygen heat exchanger first inlet; 94 - oxygen heat exchanger second outlet. DETAILED DESCRIPTION

[0028] The other advantages and effects of the present application can be easily understood by those skilled in the art from the content disclosed in the specification. The present application can also be implemented or applied in other different specific embodiments, and each detail in the specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the drawings provided in the following embodiments only illustrate the basic concept of the present application in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0029] The drawings are only used for exemplary illustration, and the representation is only a schematic diagram, not a physical diagram, and should not be understood as a limitation of the present application. In order to better illustrate the embodiments of the present application, some components in the drawings can be omitted, enlarged or reduced, and do not represent the actual size of the product. It is understandable for those skilled in the art that some known structures and their descriptions in the drawings can be omitted.

[0030] The same or similar reference signs in the drawings of the embodiments of the present application correspond to the same or similar components; in the description of the present application, it is understood that if the orientations or position relationships indicated by the terms "upper", "lower", "left", "right", "front", "back" and the like are based on the orientations or position relationships shown in the drawings, only for the convenience of describing the present application and simplifying the description, and therefore the terms describing the position relationships in the drawings are only used for exemplary illustration, and cannot be understood as a limitation on the present application; for ordinary skilled in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0031] Please refer to Figure 1 It is a kind of device based on krypton-xenon refining liquid air-oxygen-nitrogen separation, including liquid air storage tank 4, liquid pump 5, rectifying tower 1, subcooler 2, main heat exchanger 3, oxygen heat exchanger 9, liquid nitrogen storage tank 8, liquid oxygen storage tank 7, nitrogen circulating compressor 6;

[0032] Rectifying tower 1 includes tower body, regular packing arranged in the tower body, condensation evaporator integrated in the lower part of the tower body; six inlets and outlets are arranged on the tower body, which are liquid nitrogen inlet 11, liquid air inlet 12, liquid oxygen outlet 14, oxygen outlet 16, nitrogen outlet 18 and waste nitrogen outlet 17; three groups of inlets and outlets are arranged on the subcooler 2, which are subcooler first inlet 24, subcooler first outlet 21, subcooler second inlet 22, subcooler second outlet 25, subcooler third inlet 26 and subcooler third outlet 23; four groups of inlets and outlets are arranged on the main heat exchanger 3, which are main heat exchange first inlet 31, main heat exchange first outlet 35, main heat exchange second inlet 32, main heat exchange second outlet 36, main heat exchange third inlet 37, main heat exchange third outlet 33, main heat exchange fourth inlet 34 and main heat exchange fourth outlet 38; two groups of inlets and outlets are arranged on the oxygen heat exchanger 9, which are oxygen heat exchange first inlet, oxygen heat exchange first outlet, oxygen heat exchange second inlet and oxygen heat exchange second outlet;

[0033] Liquid air tank 4 is communicated with liquid air inlet 12 through liquid pump 5, nitrogen gas outlet 18 is communicated with subcooler first inlet 24, subcooler first outlet 21 is communicated with main heat exchanger first inlet 31; main heat exchanger first outlet 35 is communicated with the inlet of nitrogen gas circulating compressor 6, the outlet of nitrogen gas circulating compressor 6 is divided into two routes, one route goes to instrument gas, warming gas, purge gas header, the other route is communicated with main heat exchanger third inlet 37, main heat exchanger third outlet 33 is communicated with condenser evaporator inlet 13, condenser evaporator outlet 15 is communicated with subcooler second inlet 22, subcooler second outlet 25 is divided into two routes, one route is communicated with liquid nitrogen inlet through first throttle valve V1, the other route is divided into three routes again, the first route is connected to liquid nitrogen tank 8 through second throttle valve V2, the second route is connected to oxygen heat exchange second inlet through third throttle valve V3, the third route goes to krypton-xenon refining device as a cold source, oxygen heat exchange second outlet is communicated with the inlet of nitrogen gas circulating compressor 6, oxygen gas outlet 16 is communicated with main heat exchanger second inlet 32, main heat exchanger second outlet 36 is connected to low-pressure oxygen pipe network or connected to atmospheric venting; waste nitrogen gas outlet 17 is communicated with subcooler third inlet 26, subcooler third outlet 23 is communicated with main heat exchanger fourth inlet 34, main heat exchanger fourth outlet 38 is connected to atmospheric venting;

[0034] Oxygen heat exchange first inlet is connected to oxygen gas from krypton-xenon refining, oxygen first heat exchange outlet is connected to liquid oxygen tank 7 after being collected with liquid oxygen outlet 14 at the bottom of the tower body through fourth throttle valve V4.

[0035] As a preferred, in the embodiment, rectifying tower 1 is a structured packing reboiling absorption tower. Liquid oxygen tank 7 and liquid nitrogen tank 8 are both normal-pressure low-temperature liquid tanks. Liquid air tank 4 is a normal-pressure low-temperature liquid tank. Liquid pump 5 is a centrifugal low-temperature liquid pump 5. Condenser evaporator is a full-immersion liquid oxygen plate-fin condenser evaporator. Nitrogen gas circulating compressor 6 is a centrifugal nitrogen gas circulating compressor 6. Main heat exchanger 3, subcooler 2 and oxygen heat exchanger 9 are all plate-fin heat exchangers.

[0036] The liquid air energy storage obtained liquid air is used as raw material, pressurized by liquid pump 5 and then sent into rectification tower 1 as reflux liquid to participate in rectification; the nitrogen obtained at the top of rectification tower 1 is reheated to normal temperature by main heat exchanger 3 and subcooler 2, then sent into nitrogen circulating compressor 6 to be pressurized, and then enters main heat exchanger 3 to exchange heat and be cooled, and then returns to the rectification tower 1 bottom condenser evaporator to exchange heat with liquid oxygen, and the nitrogen partially evaporates the liquid oxygen while being condensed into liquid nitrogen, and finally the liquid nitrogen enters the subcooler 2 to be subcooled, and the subcooled liquid nitrogen flows in four paths, the first path is that part of the liquid nitrogen is throttled and then sent into liquid nitrogen storage tank 8; the second path is that part of the liquid nitrogen is throttled and then enters oxygen heat exchanger 9 to exchange heat with oxygen from krypton-xenon refining, and the gaseous oxygen is converted into liquid and sent into liquid oxygen storage tank 7, and the liquid nitrogen is gasified and then combined with the nitrogen at the top of rectification tower 1 to enter nitrogen circulating compressor 6; the third path is that the liquid nitrogen is throttled and then sent into rectification tower 1 as reflux liquid to continue to participate in rectification, and the fourth path is that the liquid nitrogen is throttled and then sent into krypton-xenon refining device as a cold source; part of the liquid oxygen at the bottom of rectification tower 1 is evaporated by nitrogen, and the other part is combined with the liquid oxygen from oxygen heat exchanger 9 and then sent into liquid oxygen storage tank 7; a small amount of oxygen product is obtained at the bottom of the rectification tower during the entire rectification process.

[0037] The nitrogen obtained by rectification is recycled, so that the device does not consume additional nitrogen except during the start-up process, and only the self-produced nitrogen is recycled for use in the device.

[0038] In the process of linkage with krypton-xenon refining, the device for separating oxygen and nitrogen from liquid air based on krypton-xenon refining not only solves the problem of cold source liquid nitrogen required by krypton-xenon refining, but also directly separates the liquid air energy storage obtained liquid air into the required liquid oxygen and nitrogen products, while avoiding the waste of a large amount of nitrogen and the consumption of energy.

[0039] The liquid air is pressurized by a liquid pump and sent into the rectification tower, the interface pressure is about 0.4 MPa, and the interface pipe diameter is DN50. The nitrogen is pressurized by a nitrogen compressor and sent into the main heat exchanger, the interface pressure is about 0.55 MPa, and the interface pipe diameter is DN200. The oxygen is introduced from the main heat exchanger to the low-pressure oxygen pipeline network or vented, the interface pressure is about 135 kPa, and the interface pipe diameter is DN40. The liquid oxygen is sent to the liquid oxygen storage tank, the interface pressure is about 145 kPa, and the interface pipe diameter is DN40. The liquid nitrogen is introduced from the subcooler to the liquid nitrogen storage tank, the interface pressure is about 0.3 MPa, and the interface pipe diameter is DN50.

[0040] The raw material used in this embodiment is: liquid air: 3000 Nm 3 / h (converted to gaseous state), 0.40 MPa. The obtained products are: liquid nitrogen: 1670 Nm 3 / h (converted to gaseous state); liquid oxygen: 1000 Nm 3 / h (converted to gaseous state); oxygen: 29 Nm 3 / h, 135 kPa.

[0041] Finally, it is explained that the above examples are merely to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced equivalently without departing from the purpose and scope of the present application, and all should be covered in the scope of the claims of the present application.

Claims

1. A device for separating oxygen from air based on krypton-xenon refined liquid, characterized in that: The liquid air storage tank, the liquid pump, the rectifying tower, the subcooler, the main heat exchanger, the oxygen heat exchanger, the liquid nitrogen storage tank, the liquid oxygen storage tank and the nitrogen circulating compressor; The rectifying tower comprises a tower body, structured packing arranged in the tower body and a condensation evaporator integrated in the lower part of the tower body; six inlets and outlets are arranged on the tower body, which are a liquid nitrogen inlet, a liquid air inlet, a liquid oxygen outlet, an oxygen outlet, a nitrogen outlet and a waste nitrogen gas outlet; three groups of inlets and outlets are arranged on the subcooler, which are a first inlet, a first outlet, a second inlet, a second outlet and a third inlet, a third outlet; four groups of inlets and outlets are arranged on the main heat exchanger, which are a first inlet, a first outlet, a second inlet, a second outlet, a third inlet, a third outlet and a fourth inlet, a fourth outlet; two groups of inlets and outlets are arranged on the oxygen heat exchanger, which are a first inlet, a first outlet, a second inlet and a second outlet. The liquid air storage tank is communicated with the liquid air inlet through the liquid pump; the nitrogen outlet is communicated with the first inlet of the subcooler; the first outlet of the subcooler is communicated with the first inlet of the main heat exchanger; the first outlet of the main heat exchanger is communicated with the inlet of the nitrogen circulating compressor; the outlet of the nitrogen circulating compressor is divided into two paths, one of which is connected to an instrument gas, a warming gas and a purge gas header, and the other of which is communicated with the third inlet of the main heat exchanger; the third outlet of the main heat exchanger is communicated with the inlet of the condensation evaporator; the outlet of the condensation evaporator is communicated with the second inlet of the subcooler; the second outlet of the subcooler is divided into two paths, one of which is communicated with the liquid nitrogen inlet through a first throttling valve, and the other of which is divided into three paths again, one of which is connected to the liquid nitrogen storage tank through a second throttling valve, one of which is connected to the second inlet of the oxygen heat exchanger through a third throttling valve, and one of which is connected to a krypton-xenon refining device as a cold source; the second outlet of the oxygen heat exchanger is communicated with the inlet of the nitrogen circulating compressor; the oxygen outlet is communicated with the second inlet of the main heat exchanger; the second outlet of the main heat exchanger is connected to a low-pressure oxygen pipe network or is connected to the atmosphere for venting; the waste nitrogen gas outlet is communicated with the third inlet of the subcooler; the third outlet of the subcooler is communicated with the fourth inlet of the main heat exchanger; the fourth outlet of the main heat exchanger is connected to the atmosphere for venting. The first inlet of the oxygen heat exchanger is connected to oxygen from krypton-xenon refining; the first outlet of the oxygen heat exchanger is connected to the liquid oxygen outlet through a fourth throttling valve and then to the liquid oxygen storage tank.

2. The device for separation of oxygen and nitrogen based on krypton-xenon refining liquid according to claim 1, characterized by the fact that: The rectifying tower is a structured packing reboiling absorption tower.

3. The device for separation of oxygen and nitrogen based on krypton-xenon refining liquid according to claim 1, characterized by the fact that: The liquid oxygen storage tank and the liquid nitrogen storage tank are both normal-pressure low-temperature liquid storage tanks.

4. The device for separation of oxygen and nitrogen based on krypton-xenon refining liquid according to claim 1, characterized by the fact that: The liquid air storage tank is a normal-pressure low-temperature liquid storage tank.

5. The device for separation of oxygen and nitrogen based on krypton-xenon refining liquid according to claim 1, characterized by the fact that: The liquid pump is a centrifugal low-temperature liquid pump.

6. The device for separation of oxygen and nitrogen based on krypton-xenon refining liquid according to claim 1, characterized by the fact that: The condensation evaporator is a full-immersion liquid oxygen finned condensation evaporator.

7. The device for separation of oxygen and nitrogen based on krypton-xenon refining liquid according to claim 1, characterized by the fact that: The nitrogen circulating compressor is a centrifugal nitrogen circulating compressor.

8. The device for separation of oxygen and nitrogen based on krypton-xenon refining liquid according to claim 1, characterized by the fact that: The main heat exchanger, the subcooler and the oxygen heat exchanger are all finned heat exchangers.

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