Single-cycle mixed refrigerant natural gas liquefaction equipment

Abstract

The utility model relates to single-cycle mixed refrigerant natural gas liquefaction equipment. The single-cycle mixed refrigerant natural gas liquefaction equipment comprises a heat exchange unit, a liquefaction assembly and a refrigeration assembly; the refrigeration assembly comprises a first compressor, a second compressor, a first cooler, a second cooler, a first gas-liquid separator and a second gas-liquid separator, the heat exchange unit comprises a heat exchange body, a first heat exchange component, a second heat exchange component, a first throttling valve and a second throttling valve, and the first throttling valve is arranged on the first heat exchange component; the second throttling valve is arranged on the second heat exchange part, and the heat exchange body is a coiled tube heat exchanger; the second gas-liquid separator conveys a gas refrigerant to the first heat exchange component, and the second gas-liquid separator conveys a liquid refrigerant to the second heat exchange component; the liquefaction assembly exchanges heat with refrigerants in the first heat exchange component and the second heat exchange component through the heat exchange body. Thus, natural gas liquefaction is achieved, the heat exchange efficiency is improved, the process complexity is reduced, and operation is easy.

Description

Technical Field

[0001] The present application relates to the technical field of natural gas liquefaction, and in particular to a single-cycle mixed refrigerant natural gas liquefaction device. Background Art

[0002] Natural gas is a high-quality, clean fossil energy source. After being liquefied, the volume of natural gas is about 1 / 600 of the original, so it is easy to store and transport. Compared with pipeline gas, liquefied natural gas (LNG) plays an irreplaceable role in the development of scattered gas fields, marginal gas fields, the utilization of coalbed methane, the development and utilization of offshore natural gas, and the introduction of overseas natural gas. There are three types of natural gas liquefaction: cascade refrigeration cycle, refrigerant refrigeration cycle, and expansion mechanism refrigeration cycle. Among them, the refrigerant cycle (MRC) process is relatively simple, with high energy utilization efficiency and low energy consumption, so it is the most commonly used.

[0003] In particular, the single-cycle mixed refrigerant liquefaction process (SMR) is widely used in small and medium-sized liquefaction units. In order to maintain a high liquefaction efficiency, the refrigerant in the single-cycle mixed refrigerant liquefaction process (SMR) is usually composed of nitrogen and hydrocarbon mixtures. During the staged compression and intermediate cooling, some liquid refrigerant will condense out. Based on the different treatments of liquid refrigerants, there are currently two main single-cycle mixed refrigerant liquefaction process technologies:

[0004] The first one: This process adopts two-stage compression cooling. After intermediate cooling, the refrigerant is gas-liquid two-phase. The gas-phase refrigerant enters the inlet of the second-stage compressor, and the liquid-phase refrigerant is pressurized by the refrigerant pump and remixed with the refrigerant at the outlet of the second-stage compressor. After condensation, it enters the gas-liquid separator. The high-pressure refrigerant gas and refrigerant liquid enter the cold box through pipelines respectively. The liquid refrigerant is transported by the refrigerant pump. The gas and liquid refrigerants are mixed in the brazed aluminum core of the cold box. Only one JT valve is needed for one core.

[0005] The second type: This process also uses two-stage compression cooling. After intermediate cooling, the refrigerant is gas-liquid two-phase, in which the gas-phase refrigerant enters the inlet of the second-stage compressor, and the liquid-phase refrigerant is set up in a separate flow channel to enter the cold box and is throttled and refrigerated by a separate JT valve. At the same time, in the technical solution of this process, the refrigerant after the second-stage compression and cooling of the compressor is also gas-liquid two-phase, and a second gas-liquid separation tank needs to be set up. This process also sets up flow channels for the gas and liquid two-phase refrigerants obtained in the second gas-liquid separation tank, and uses independent JT valves for throttling and refrigeration, so there are a total of three refrigerant flow channels and three JT valves.

[0006] However, the first process of the single-cycle mixed refrigerant liquefaction process uses a JT valve with low efficiency, and the second process uses a separate flow channel for the primary and secondary gas and liquid phase refrigerants to enter the cold box, and uses three JT valves, which is complex. Summary of the invention

[0007] Based on this, it is necessary to provide a single-cycle mixed refrigerant natural gas liquefaction equipment to address the problems of low heat exchange efficiency and complex process in the current single-cycle mixed refrigerant liquefaction process of natural gas, which can liquefy gaseous natural gas into liquid natural gas while ensuring heat exchange efficiency and liquefaction efficiency, reducing the complexity of the liquefaction process and facilitating operation.

[0008] A single-cycle mixed refrigerant natural gas liquefaction device comprises a heat exchange unit, a liquefaction component and a refrigeration component;

[0009] The refrigeration assembly includes a first compressor, a second compressor, a first cooler, a second cooler, a first gas-liquid separator, and a second gas-liquid separator, and the heat exchange unit, the first compressor, the first cooler, the first gas-liquid separator, the second compressor, the second cooler, and the second gas-liquid separator are connected in series to form a refrigeration circuit for the refrigerant to flow;

[0010] The heat exchange unit comprises a heat exchange body, a first heat exchange component, a second heat exchange component, a first throttle valve and a second throttle valve, wherein the first heat exchange component and the second heat exchange component are arranged in the heat exchange body, the first throttle valve is arranged in the first heat exchange component, and the second throttle valve is arranged in the second heat exchange component, wherein the heat exchange body is a coiled heat exchanger;

[0011] The second gas-liquid separator delivers the gas refrigerant to the first heat exchange component, and the second gas-liquid separator delivers the liquid refrigerant to the second heat exchange component;

[0012] The liquefaction component exchanges heat with the refrigerant in the first heat exchange component and the second heat exchange component through the heat exchange body.

[0013] In one embodiment of the present application, the first heat exchange component includes a first heat exchange pipeline, and the second heat exchange component also includes a second heat exchange pipeline, and the first heat exchange pipeline and the second heat exchange pipeline are arranged on the heat exchange body along the vertical direction;

[0014] The liquefaction component includes a liquefaction pipeline, a first pipe portion and a second pipe portion. The liquefaction pipeline is arranged in the heat exchange body and is arranged in parallel with the first heat exchange pipeline and the second heat exchange pipeline. The first pipe portion and the second pipe portion are arranged at both ends of the liquefaction pipeline.

[0015] In one embodiment of the present application, inlet ends of the first heat exchange pipeline and the second heat exchange pipeline are located at the bottom of the heat exchange body, and the refrigerant flows from bottom to top in the first heat exchange pipeline and the second heat exchange pipeline.

[0016] In one embodiment of the present application, the first heat exchange component also includes a third heat exchange pipeline, the second heat exchange component also includes a fourth heat exchange pipeline, the third heat exchange pipeline is connected to the first heat exchange pipeline, the first throttle valve is arranged between the third heat exchange pipeline and the first heat exchange pipeline, the fourth heat exchange pipeline is connected to the second heat exchange pipeline, and the second throttle valve is arranged between the fourth heat exchange pipeline and the second heat exchange pipeline.

[0017] In one embodiment of the present application, the first heat exchange component further includes a first connecting pipe, and the second heat exchange component further includes a second connecting pipe;

[0018] The first connecting pipe connects the first heat exchange pipeline and the third heat exchange pipeline, and the second connecting pipe connects the second heat exchange pipeline and the fourth heat exchange pipeline;

[0019] The first throttle valve is disposed on the first connecting pipe, and the second throttle valve is disposed on the second connecting pipe.

[0020] In one embodiment of the present application, the first connecting pipe, the second connecting pipe, the first throttle valve, and the second throttle valve are located outside the heat exchange body.

[0021] In one embodiment of the present application, the third heat exchange pipeline and the fourth heat exchange pipeline are spray pipes and extend in the horizontal direction, and the third heat exchange pipeline is located at the top of the heat exchange body, and the fourth heat exchange pipeline is located in the middle of the heat exchange body;

[0022] Alternatively, the third heat exchange pipeline and the fourth heat exchange pipeline are heat exchange coils or heat exchange straight pipes.

[0023] In one embodiment of the present application, the first gas-liquid separator has a first gas outlet pipe and a first liquid outlet pipe, the first gas outlet pipe is connected to the second compressor, the first liquid outlet pipe is connected to the output port of the second compressor, and is connected to the second cooler;

[0024] And / or, the second gas-liquid separator has a second gas outlet pipe and a second liquid outlet pipe, the second gas outlet pipe is connected to the first heat exchange component, and the second liquid outlet pipe is connected to the second heat exchange component.

[0025] In one embodiment of the present application, the refrigeration assembly further includes a third gas-liquid separator, and the third gas-liquid separator is disposed between the heat exchange body and the first compressor;

[0026] And / or, the refrigeration assembly further includes a booster pump, and the booster pump is arranged between the first liquid outlet pipe of the first gas-liquid separator and the second cooler.

[0027] In an embodiment of the present application, the refrigeration assembly further includes a driving member, and the driving member is connected to the first compressor and the second compressor at the same time.

[0028] After adopting the above technical solution, this application has at least the following technical effects:

[0029] In the single-cycle mixed refrigerant natural gas liquefaction equipment of the present application, a heat exchange unit, a first compressor, a first cooler, a first gas-liquid separator, a second compressor, a second cooler and a second gas-liquid separator are connected in series to form a refrigeration circuit, and the refrigerant circulates in the refrigeration circuit. The second gas-liquid separator transports the gaseous refrigerant to the first heat exchange component, and the second gas-liquid separator transports the liquid refrigerant to the second heat exchange component. The first heat exchange component and the second heat exchange component are arranged in the heat exchange body. In this way, after the gaseous natural gas enters the liquefaction component, it can exchange heat with the refrigerant in the heat exchange body, the first heat exchange component and the second heat exchange component to output liquefied natural gas.

[0030] The single-cycle mixed refrigerant natural gas liquefaction equipment uses a refrigeration component to achieve two-stage compression of the refrigerant, and transports the compressed gas refrigerant and liquid refrigerant to the first heat exchange component and the second heat exchange component of the heat exchange unit respectively, so as to exchange heat with the gaseous natural gas in the liquefaction component, output liquefied natural gas, and realize the liquefaction of natural gas. In addition, the first throttle valve and the second throttle valve are used to cool and gasify the refrigerant in the first heat exchange component and the second heat exchange component respectively, so as to improve the heat exchange efficiency and liquefaction efficiency, reduce the complexity of the liquefaction equipment and the liquefaction process, and facilitate operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic diagram of the principle of a single-cycle mixed refrigerant natural gas liquefaction device according to an embodiment of the present application.

[0032] Figure 2 for Figure 1 The schematic diagram of the refrigeration components in the single-cycle mixed refrigerant natural gas liquefaction equipment is shown.

[0033] Figure 3 for Figure 1 The schematic diagram of the heat exchange unit in the single-cycle mixed refrigerant natural gas liquefaction equipment is shown.

[0034] Figure 4 for Figure 1 The process flow diagram of a single-cycle mixed refrigerant natural gas liquefaction equipment is shown.

[0035] Wherein: 100, single cycle mixed refrigerant natural gas liquefaction equipment; 110, heat exchange unit; 111, heat exchange body; 112, first heat exchange component; 1121, first heat exchange pipeline; 1122, third heat exchange pipeline; 1123, first connecting pipe; 113, second heat exchange component; 1131, second heat exchange pipeline; 1132, fourth heat exchange pipeline; 1133, second connecting pipe; 114, first throttle valve; 115, second throttle valve; 120, liquefaction component; 121, liquid chemical pipeline; 122, the first pipe part; 123, the second pipe part; 130, the refrigeration component; 131, the first compressor; 132, the second compressor; 133, the first cooler; 134, the second cooler; 135, the first gas-liquid separator; 1351, the first air outlet pipe; 1352, the first liquid outlet pipe; 136, the second gas-liquid separator; 1361, the second air outlet pipe; 1362, the second liquid outlet pipe; 137, the booster pump; 138, the third gas-liquid separator; 139, the driving member. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0037] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0038] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0039] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0040] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0041] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0042] See also Figure 1 , the present application provides a single-cycle mixed refrigerant natural gas liquefaction device 100. Figure 1 The schematic diagram of the principle of a single-cycle mixed refrigerant natural gas liquefaction device 100 according to an embodiment of the present application is shown in FIG. The single-cycle mixed refrigerant natural gas liquefaction device 100 can liquefy gaseous natural gas into liquid natural gas to facilitate the storage and transportation of natural gas.

[0043] It is understandable that the current single-cycle mixed refrigerant liquefaction process of natural gas either has low heat exchange efficiency or is complex. To this end, the present application provides a novel single-cycle mixed refrigerant natural gas liquefaction device 100, which can liquefy gaseous natural gas into liquid natural gas, while also ensuring heat exchange efficiency and liquefaction efficiency, reducing the complexity of the liquefaction process, and facilitating operation. The specific structure of the single-cycle mixed refrigerant natural gas liquefaction device 100 of an embodiment is introduced below.

[0044] See also Figure 1 In one embodiment, the single-cycle mixed refrigerant natural gas liquefaction equipment 100 includes a heat exchange unit 110, a liquefaction component 120 and a refrigeration component 130. The refrigeration component 130 includes a first compressor 131, a second compressor 132, a first cooler 133, a second cooler 134, a first gas-liquid separator 135 and a second gas-liquid separator 136. The heat exchange unit 110, the first compressor 131, the first cooler 133, the first gas-liquid separator 135, the second compressor 132, the second cooler 134 and the second gas-liquid separator 136 are connected in series to form a refrigeration circuit for the refrigerant to flow. The heat exchange unit 110 includes a heat exchange body 111, a first heat exchange component 112, a second heat exchange component 113, a first throttle valve 114, and a second throttle valve 115. The first heat exchange component 112 and the second heat exchange component 113 are arranged in the heat exchange body 111, the first throttle valve 114 is arranged in the first heat exchange component 112, and the second throttle valve 115 is arranged in the second heat exchange component 113. The second gas-liquid separator 136 transports the gas refrigerant to the first heat exchange component 112, and the second gas-liquid separator 136 transports the liquid refrigerant to the second heat exchange component 113. The liquefaction component 120 exchanges heat with the refrigerants in the first heat exchange component 112 and the second heat exchange component 113 through the heat exchange body 111.

[0045] The refrigeration assembly 130 is connected to the heat exchange unit 110, and the liquefaction assembly 120 extends through the heat exchange unit 110. The refrigeration assembly 130 and the liquefaction assembly 120 are connected in parallel through the heat exchange unit 110. The refrigeration assembly 130 is used for circulating the refrigerant, and the liquefaction assembly 120 is used for flowing the natural gas. The heat exchange unit 110 can realize the heat exchange between the refrigerant in the refrigeration assembly 130 and the natural gas in the refrigeration assembly 130. The gaseous natural gas enters the liquefaction assembly 120 from one end of the heat exchange unit 110, and forms liquefied natural gas after heat exchange with the low-temperature refrigerant in the heat exchange unit 110. The liquefied natural gas flows out from the other end of the liquefaction assembly 120.

[0046] The refrigeration component 130 can cool the refrigerant so that the low-temperature refrigerant enters the heat exchange unit 110. After the gaseous natural gas enters the refrigeration component 130, it can exchange heat with the refrigerant in the heat exchange unit 110. The gaseous natural gas releases heat and liquefies into liquid natural gas. Subsequently, the liquefaction component 120 outputs the liquefied natural gas to achieve the liquefaction of natural gas. The refrigerant in the heat exchange unit 110 absorbs heat and returns to the refrigeration component 130. The refrigeration component 130 cools the refrigerant and returns to the heat exchange unit 110 to continue to liquefy the gaseous natural gas. The refrigerant circulates to cool and absorb heat to achieve continuous liquefaction of natural gas. The refrigerant is a mixed refrigerant. It is worth noting that the type of mixed refrigerant is a prior art and will not be described in detail here.

[0047] Specifically, the input port of the first compressor 131 is connected to the heat exchange body 111 of the heat exchange unit 110, the output port of the first compressor 131 is connected to the input end of the first cooler 133, the output end of the first cooler 133 is connected to the inlet of the first gas-liquid separator 135, the outlet of the first gas-liquid separator 135 is respectively connected to the input port of the second compressor 132 and the output port of the second compressor 132, the output port of the second compressor 132 is also connected to the input end of the second cooler 134, the output end of the second cooler 134 is connected to the inlet of the second gas-liquid separator 136, the outlet of the second gas-liquid separator 136 is respectively connected to the first heat exchange component 112 and the second heat exchange component 113 of the heat exchange unit 110, and the first heat exchange component 112 and the second heat exchange component 113 are also connected to the heat exchange body 111. In this way, the heat exchange unit 110, the first compressor 131, the first cooler 133, the first gas-liquid separator 135, the second compressor 132, the second cooler 134 and the second gas-liquid separator 136 are connected in series to form a refrigeration circuit, and the refrigerant flows in the refrigeration circuit.

[0048] The high-temperature refrigerant after absorbing heat in the heat exchange body 111 enters the first compressor 131. After being compressed by the first compressor 131, the refrigerant is transported to the first cooler 133 for condensation. The condensed refrigerant enters the first gas-liquid separator 135, and the gas-liquid mixed refrigerant is separated by the first gas-liquid separator 135. The first gas-liquid separator 135 transports the gas refrigerant to the second compressor 132, and transports the liquid refrigerant to the output port of the second compressor 132. The second compressor 132 compresses the gas refrigerant and outputs it, and after mixing with the liquid refrigerant transported by the first gas-liquid separator 135, it enters the second cooler 134 for condensation. The condensed refrigerant enters the second gas-liquid separator 136, and the gas-liquid mixed refrigerant is separated by the second gas-liquid separator 136. The second gas-liquid separator 136 transports the gas refrigerant to the first heat exchange component 112, and transports the liquid refrigerant to the second heat exchange component 113. At this time, the first heat exchange component 112 exchanges heat with the gaseous natural gas in the liquefaction component 120 through the gas refrigerant, and the second heat exchange component 113 exchanges heat with the gaseous natural gas in the liquefaction component 120 through the liquid refrigerant, thereby liquefying the natural gas.

[0049] Moreover, after the first heat exchange component 112 and the second heat exchange component 113 exchange heat with the gaseous natural gas in the liquefied component 120, the first throttle valve 114 and the second throttle valve 115 can also cool down the refrigerant absorbing heat in the first heat exchange component 112 and the second heat exchange component 113. Specifically, the first throttle valve 114 is provided in the first heat exchange component 112, and the second throttle valve 115 is provided in the second heat exchange component 113. The first throttle valve 114 can cause the refrigerant in the first heat exchange component 112 to throttle and expand to reduce the temperature of the refrigerant therein, and the second throttle valve 115 can cause the refrigerant in the second heat exchange component 113 to throttle and expand to reduce the temperature of the refrigerant therein. In this way, the refrigerants in the first heat exchange component 112 and the second heat exchange component 113 are both at a lower temperature, which can better exchange heat with the gaseous natural gas in the liquefied component 120, so that the liquefied component 120 outputs liquefied natural gas, thereby realizing the liquefaction of natural gas.

[0050] That is, the first heat exchange component 112 and the second heat exchange component 113 first cool down the gaseous natural gas in the liquefied component 120 in the heat exchange body 111, and then throttle expansion and cool down the refrigerant through the first throttle valve 114 and the second throttle valve 115, so as to cool down the first heat exchange component 112 and the second heat exchange component 113 and the gaseous natural gas in the liquefied component 120 again. At the same time, the first throttle valve 114 cooperates with the first heat exchange component 112, and the second throttle valve 115 cooperates with the second heat exchange component 113, so as to ensure the flow rate of the low-temperature refrigerant, thereby improving the heat exchange efficiency and liquefaction efficiency of the natural gas.

[0051] Since the first throttle valve 114 is arranged on the first heat exchange component 112, the second throttle valve 115 is arranged on the second heat exchange component 113, and the second gas-liquid separator 136 transports the gaseous refrigerant to the first heat exchange component 112 and transports the liquid refrigerant to the second heat exchange component 113, the first throttle valve 114 throttles and expands the gaseous refrigerant, and the second throttle valve 115 can throttle and expand the liquid refrigerant. Two flow channels are used in conjunction with two throttle valves to transport low-temperature refrigerant, which reduces the complexity of liquefaction equipment and liquefaction process while ensuring heat exchange efficiency, and facilitates operation.

[0052] The single-cycle mixed refrigerant natural gas liquefaction equipment 100 of the above embodiment uses a refrigeration component 130 to achieve two-stage compression of the refrigerant, and the compressed gas refrigerant and liquid refrigerant are respectively transported to the first heat exchange component 112 and the second heat exchange component 113 of the heat exchange unit 110 to exchange heat with the gaseous natural gas in the liquefaction component 120 to output liquefied natural gas to achieve liquefaction of natural gas. In addition, the first throttle valve 114 and the second throttle valve 115 are used to cool and gasify the refrigerant in the first heat exchange component 112 and the second heat exchange component 113, respectively, to improve the heat exchange efficiency and liquefaction efficiency, and reduce the complexity of the liquefaction equipment and the liquefaction process, which is easy to operate.

[0053] See also Figure 1 and Figure 2 In one embodiment, the first gas-liquid separator 135 has a first gas outlet pipe 1351 and a first liquid outlet pipe 1352 , the first gas outlet pipe 1351 is connected to the second compressor 132 , the first liquid outlet pipe 1352 is connected to the output port of the second compressor 132 , and is connected to the second cooler 134 . Figure 2 for Figure 1 The schematic diagram of the refrigeration assembly 130 in the single-cycle mixed refrigerant natural gas liquefaction equipment 100 is shown.

[0054] The inlet of the first gas-liquid separator 135 is connected to the outlet of the first cooler 133. The first cooler 133 condenses the refrigerant compressed by the first compressor 131 and transports it to the first gas-liquid separator 135. At this time, the refrigerant is a gas-liquid mixture. The first gas-liquid separator 135 can separate the gas refrigerant from the liquid refrigerant. The first gas-liquid separator 135 is connected to the second compressor 132 through the first gas outlet pipe 1351, and the first gas-liquid separator 135 is connected to the output port of the second compressor 132 through the first liquid outlet pipe 1352. The first gas-liquid separator 135 transports the gas refrigerant to the second compressor 132 through the first gas outlet pipe 1351 for compression, and the first gas-liquid separator 135 transports the liquid refrigerant to the output port of the second compressor 132 through the first liquid outlet pipe 1352, and after mixing with the refrigerant compressed by the second compressor 132, it is transported to the second cooler 134 for condensation.

[0055] Optionally, the first air outlet pipe 1351 and the first liquid outlet pipe 1352 are an integral structure with the first gas-liquid separator 135. Of course, in other embodiments of the present application, the first air outlet pipe 1351 and the first liquid outlet pipe 1352 can also be separately arranged from the first gas-liquid separator 135, and the first air outlet pipe 1351 and the first liquid outlet pipe 1352 are connected to the corresponding outlets of the first gas-liquid separator 135. Moreover, the arrangement of the first air outlet pipe 1351 and the first liquid outlet pipe 1352 is not limited in principle, as long as the corresponding components can be connected.

[0056] See also Figure 1 and Figure 2 In one embodiment, the second gas-liquid separator 136 has a second gas outlet pipe 1361 and a second liquid outlet pipe 1362, the second gas outlet pipe 1361 is connected to the first heat exchange component 112, and the second liquid outlet pipe 1362 is connected to the second heat exchange component 113. The inlet of the second gas-liquid separator 136 is connected to the outlet of the second cooler 134, and the second cooler 134 condenses the refrigerant compressed by the second compressor 132 and the liquid refrigerant output by the first gas-liquid separator 135 and transports them to the second gas-liquid separator 136. At this time, the refrigerant is a gas-liquid mixture. The second gas-liquid separator 136 can separate the gas refrigerant from the liquid refrigerant.

[0057] The second gas-liquid separator 136 is connected to the first heat exchange component 112 through the second gas outlet pipe 1361, and the second gas-liquid separator 136 is connected to the second heat exchange component 113 through the second liquid outlet pipe 1362. The second gas-liquid separator 136 delivers the gaseous refrigerant to the first heat exchange component 112 through the second gas outlet pipe 1361, and the second gas-liquid separator 136 delivers the liquid refrigerant to the second heat exchange component 113 through the second liquid outlet pipe 1362. The first heat exchange component 112 exchanges heat with the gaseous natural gas through the gaseous refrigerant therein, and the second heat exchange component 113 exchanges heat with the gaseous natural gas through the liquid refrigerant therein.

[0058] Optionally, the second air outlet pipe 1361 and the second liquid outlet pipe 1362 are an integral structure with the second gas-liquid separator 136. Of course, in other embodiments of the present application, the second air outlet pipe 1361 and the second liquid outlet pipe 1362 can also be separately arranged from the second gas-liquid separator 136, and the second air outlet pipe 1361 and the second liquid outlet pipe 1362 are connected to the corresponding outlets of the second gas-liquid separator 136. Moreover, the arrangement of the second air outlet pipe 1361 and the second liquid outlet pipe 1362 is not limited in principle, as long as the corresponding components can be connected.

[0059] See also Figure 1 In one embodiment, the refrigeration assembly 130 further includes a booster pump 137, and the booster pump 137 is disposed between the first liquid outlet pipe 1352 of the first gas-liquid separator 135 and the second cooler 134. That is, the booster pump 137 is disposed between the first gas-liquid separator 135 and the output port of the second compressor 132, and thus the booster pump 137 is located between the first gas-liquid separator 135 and the second cooler 134. The booster pump 137 can increase the liquid refrigerant output from the first gas-liquid separator 135, so as to directly mix the liquid refrigerant with the refrigerant compressed by the second compressor 132, so that the refrigerant can enter the first heat exchange component 112 and the second heat exchange component 113 after passing through the second cooler 134 and the second gas-liquid separator 136.

[0060] The present application sets a booster pump 137 at the first liquid outlet pipe 1352 of the first gas-liquid separator 135. The booster pump 137 can boost the refrigerant in the refrigeration circuit to meet the flow requirements of the refrigerant in the entire refrigeration circuit, thereby meeting the liquefaction heat exchange requirements of natural gas. Moreover, using a booster pump 137 for boosting reduces the number of moving equipment in the entire liquefaction equipment, thereby reducing the complexity of the liquefaction equipment and the liquefaction process, and facilitating operation.

[0061] See also Figure 1 In one embodiment, the refrigeration assembly 130 further includes a driving member 139, and the driving member 139 is connected to the first compressor 131 and the second compressor 132 at the same time. The driving member 139 drives the driving components of the first compressor 131 and the second compressor 132 so that the first compressor 131 and the second compressor 132 can work normally. Optionally, the driving member 139 is an electric motor. Of course, in other embodiments of the present application, the driving member 139 can also be an electric motor, etc.

[0062] See also Figure 1 In one embodiment, the refrigeration assembly 130 further includes a third gas-liquid separator 138, which is disposed between the heat exchange body 111 and the first compressor 131. The third gas-liquid separator 138 can separate the high-temperature refrigerant output by the heat exchange body 111 into gas and liquid. It is understandable that if the liquid refrigerant enters the first compressor 131, it will cause liquid hammer to the first compressor 131, affecting the performance of the first compressor 131.

[0063] It can be understood that the heat exchange body 111 generally outputs a gas refrigerant. In order to avoid the possibility of liquid refrigerant, the present application sets a third gas-liquid separator 138 between the heat exchange body 111 and the first compressor 131. The third gas-liquid separator 138 can separate the liquid refrigerant from the gas refrigerant, thereby transporting the gas refrigerant to the first compressor 131, avoiding the liquid refrigerant from being transported to the first compressor 131, and ensuring that the first compressor 131 can operate reliably. Moreover, the third gas-liquid separator 138 also has a gas-liquid conversion tube, which can convert the liquid refrigerant in the third gas-liquid separator 138 into a gas refrigerant.

[0064] See also Figure 1 and Figure 3 In one embodiment, the heat exchange body 111 is a coiled tube heat exchanger. Figure 3 for Figure 1The schematic diagram of the heat exchange unit 110 in the single-cycle mixed refrigerant natural gas liquefaction equipment 100 is shown. That is, the present application uses a tubular heat exchanger as the heat exchange body 111 to cool the gaseous natural gas in the liquefaction component 120 to achieve the liquefaction of natural gas. The single volume of the coil heat exchanger is large. After the single-cycle mixed refrigerant natural gas liquefaction equipment 100 of the present application uses the coil heat exchanger for heat exchange, the single-line output of the single-cycle mixed refrigerant natural gas liquefaction equipment 100 can be increased.

[0065] Of course, in other embodiments of the present application, the heat exchange body 111 may also be a fin heat exchanger. It is worth noting that the heat exchange principle of the coil heat exchanger and the fin heat exchanger is substantially the same, except that in the coil heat exchanger, the refrigerant flows from bottom to top, and the gaseous natural gas in the liquefied component 120 flows from bottom to top, while in the fin heat exchanger, the refrigerant flows from top to bottom, and the gaseous natural gas in the liquefied component 120 flows from top to bottom. The setting of the refrigeration component 130 is substantially the same. In this embodiment, the heat exchange body 111 is only used as an example of a coil heat exchanger for explanation.

[0066] See also Figure 1 and Figure 3 In one embodiment, the first heat exchange component 112 includes a first heat exchange pipeline 1121, and the second heat exchange component 113 also includes a second heat exchange pipeline 1131. The first heat exchange pipeline 1121 and the second heat exchange pipeline 1131 are arranged in the heat exchange body 111 along the vertical direction. The liquefaction component 120 includes a liquefaction pipeline 121, a first pipe portion 122 and a second pipe portion 123. The liquefaction pipeline 121 is arranged in the heat exchange body 111 and is arranged in parallel with the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131. The first pipe portion 122 and the second pipe portion 123 are arranged at both ends of the liquefaction pipeline 121.

[0067] The first heat exchange pipeline 1121 and the second heat exchange pipeline 1131 are main components for realizing heat exchange of natural gas. The first heat exchange pipeline 1121 and the second heat exchange pipeline 1131 are arranged in the heat exchange body 111, and the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131 can exchange heat with gaseous natural gas in the liquefaction assembly 120. Moreover, in the liquefaction assembly 120, the first pipe portion 122 is an inlet pipe, the second pipe portion 123 is an outlet pipe, the first pipe portion 122 is arranged at one end of the liquefaction pipeline 121, and the second pipe portion 123 is arranged at the other end of the liquefaction pipeline 121. The liquefaction pipeline 121 is located in the heat exchange body 111 and is arranged in parallel with the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131. The first pipe portion 122 and the second pipe portion 123 are located outside the heat exchange body 111.

[0068] The liquefied pipeline 121 can exchange heat with the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131. In this way, the refrigeration component 130 delivers the gaseous refrigerant to the first heat exchange pipeline 1121 through the second gas outlet pipe 1361, and delivers the liquid refrigerant to the second heat exchange pipeline 1131 through the second liquid outlet pipe 1362. At the same time, the liquefied natural gas enters the liquefied pipeline 121 through the first pipeline 122. At this time, the gaseous natural gas in the liquefied pipeline 121 can absorb the coldness of the refrigerants in the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131 to liquefy into liquefied natural gas, and output it through the second pipe portion 123.

[0069] Optionally, the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131 are arranged around the liquefaction pipeline 121. In this way, the heat exchange area between the liquefaction pipeline 121 and the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131 can be increased, thereby ensuring the heat exchange effect and the liquefaction effect.

[0070] See also Figure 1 and Figure 3 In one embodiment, the inlet ends of the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131 are located at the bottom of the heat exchange body 111, and the refrigerant flows from bottom to top in the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131. In other words, the gas refrigerant flows from bottom to top in the first heat exchange pipeline 1121, and the liquid refrigerant flows from bottom to top in the second heat exchange pipeline 1131, and cools down the gaseous natural gas flowing from bottom to top in the liquefaction pipeline 121 to ensure the liquefaction effect.

[0071] In one embodiment, the height of the first heat exchange pipeline 1121 is higher than that of the second heat exchange pipeline 1131. That is, in the heat exchange body 111, the dimension of the first heat exchange pipeline 1121 in the vertical direction is higher than that of the second heat exchange pipeline 1131 in the vertical direction. It can be understood that the flow resistance of the gas refrigerant is smaller than that of the liquid refrigerant. After the height of the first heat exchange pipeline 1121 is set higher than that of the second heat exchange pipeline 1131, the flow path of the gas refrigerant in the first heat exchange pipeline 1121 can be made larger than the flow path of the liquid refrigerant in the second heat exchange pipeline 1131, so as to increase the heat exchange area and ensure the liquefaction effect of the gaseous natural gas in the liquefied pipeline 121.

[0072] It can be understood that the temperature of the gaseous natural gas at the lower end of the liquefied pipeline 121 is higher than that at the upper end, so the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131 are arranged at the lower end of the liquefied pipeline 121, and the first heat exchange pipeline 1121 is arranged at the upper end of the liquefied pipeline 121. In this way, the temperature of the gaseous natural gas gradually decreases during the flow from bottom to top, the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131 cool down the gaseous natural gas in the liquefied pipeline 121 at the lower end of the liquefied pipeline 121, and the first heat exchange pipeline 1121 liquefies the gaseous natural gas in the liquefied pipeline 121 at the upper end of the liquefied pipeline 121 to achieve liquefaction of the gaseous natural gas.

[0073] See also Figure 1 and Figure 3 Optionally, the first heat exchange pipeline 1121 can extend to the top of the heat exchange body 111, and the second heat exchange pipeline 1131 can extend to the middle of the heat exchange body 111. In this way, it can be ensured that the first heat exchange pipeline 1121 covers the liquefaction pipeline 121 as much as possible in the height direction, and the second heat exchange pipeline 1131 covers the liquefaction pipeline 121 as much as possible while ensuring the flow of liquid refrigerant, so as to increase the heat exchange area and ensure the heat exchange effect. Of course, in other embodiments of the present application, the height dimensions of the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131 can also be other, as long as the liquefaction of gaseous natural gas can be guaranteed.

[0074] See also Figure 1 and Figure 3 In one embodiment, the first heat exchange component 112 also includes a third heat exchange pipeline 1122, the second heat exchange component 113 also includes a fourth heat exchange pipeline 1132, the third heat exchange pipeline 1122 is connected to the first heat exchange pipeline 1121, the first throttle valve 114 is arranged between the third heat exchange pipeline 1122 and the first heat exchange pipeline 1121, the fourth heat exchange pipeline 1132 is connected to the second heat exchange pipeline 1131, and the second throttle valve 115 is arranged between the fourth heat exchange pipeline 1132 and the second heat exchange pipeline 1131.

[0075] After the refrigerant in the first heat exchange pipeline 1121 absorbs the heat of the gaseous natural gas in the liquefied pipeline 121, it is throttled, expanded, and cooled by the first throttle valve 114, and the low-temperature refrigerant enters the third heat exchange pipeline 1122. At this time, the refrigerant in the third heat exchange pipeline 1122 can cool the refrigerant in the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131, and the gaseous natural gas in the liquefied pipeline 121. Similarly, after the refrigerant in the second heat exchange pipeline 1131 absorbs the heat of the gaseous natural gas in the liquefied pipeline 121, it is throttled, expanded, and cooled by the second throttle valve 115, and the low-temperature refrigerant enters the fourth heat exchange pipeline 1132. At this time, the refrigerant in the fourth heat exchange pipeline 1132 can cool the refrigerant in the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131, and the gaseous natural gas in the liquefied pipeline 121.

[0076] That is to say, the present application utilizes the second cooler 134 and the second gas-liquid separator 136 to transport the low-temperature gas refrigerant and the liquid refrigerant to the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131, respectively, so as to cool down the gaseous natural gas in the liquefaction pipeline 121. After the refrigerant in the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131 absorbs heat, it is throttled and expanded and cooled by the first throttle valve 114 and the second throttle valve 115. The refrigerant after absorbing heat becomes a low-temperature refrigerant, which can cool down the refrigerant in the first heat exchange pipeline 1121, the second heat exchange pipeline 1131 and the gaseous natural gas in the liquefaction pipeline 121, thereby improving the heat exchange efficiency and ensuring the liquefaction effect.

[0077] See also Figure 4 In one embodiment, the third heat exchange pipeline 1122 and the fourth heat exchange pipeline 1132 are spray pipes and extend in the horizontal direction, that is, the first heat exchange component 112 includes a first spray pipe, the second heat exchange component 113 includes a second spray pipe, and the first spray pipe and the second spray pipe extend in the horizontal direction. In this way, after the first throttle valve 114 throttles and expands the refrigerant after absorbing heat in the first heat exchange pipeline 1121 and cools it, it sprays the low-temperature refrigerant through the third heat exchange pipeline 1122 which is a spray pipe, so as to cool the refrigerant in the first heat exchange pipeline 1121, the second heat exchange pipeline 1131 and the gaseous natural gas in the liquefied pipeline 121. After the second throttle valve 115 throttles, expands and cools the refrigerant after absorbing heat in the second heat exchange pipeline 1131, it sprays low-temperature refrigerant through the fourth heat exchange pipeline 1132 which is a spray pipe to cool the refrigerant in the first heat exchange pipeline 1121, the second heat exchange pipeline 1131 and the gaseous natural gas in the liquefied pipeline 121.

[0078] In one embodiment, the third heat exchange pipeline 1122 is located above the fourth heat exchange pipeline 1132. That is, the first spray pipe is located above the second spray pipe. In this way, the low-temperature refrigerant in the third heat exchange pipeline 1122 can be sprayed from top to bottom to provide low-temperature cooling, and the low-temperature refrigerant in the fourth heat exchange pipeline 1132 can be sprayed from top to bottom to provide high-temperature cooling, so as to cool the refrigerant in the first heat exchange pipeline 1121, the second heat exchange pipeline 1131 and the gaseous natural gas in the liquefied pipeline 121. Exemplarily, the third heat exchange pipeline 1122 is located at the top of the heat exchange body 111, and the fourth heat exchange pipeline 1132 is located in the middle of the heat exchange body 111. That is, the first spray pipe is located at the top of the heat exchange body 111, and the second spray pipe is located in the middle of the heat exchange body 111.

[0079] Of course, in other embodiments of the present application, the third heat exchange pipeline 1122 and the fourth heat exchange pipeline 1132 may also be heat exchange coils, heat exchange straight pipes or other types of heat exchange components. In this embodiment, the third heat exchange pipeline 1122 and the fourth heat exchange pipeline 1132 extend in the vertical direction and are arranged around the first heat exchange pipeline 1121, the second heat exchange pipeline 1131 and the liquefied pipeline 121 to cool the refrigerant in the first heat exchange pipeline 1121 and the second heat exchange pipeline 1131 and the gaseous natural gas in the liquefied pipeline 121.

[0080] See also Figure 1 and Figure 3 In one embodiment, the first heat exchange component 112 also includes a first connecting pipe 1123, and the second heat exchange component 113 also includes a second connecting pipe 1133; the first connecting pipe 1123 connects the first heat exchange pipeline 1121 and the third heat exchange pipeline 1122, and the second connecting pipe 1133 connects the second heat exchange pipeline 1131 and the fourth heat exchange pipeline 1132; the first throttle valve 114 is provided on the first connecting pipe 1123, and the second throttle valve 115 is provided on the second connecting pipe 1133.

[0081] The first connecting pipe 1123 is used to realize the connection between the first heat exchange pipeline 1121 and the third heat exchange pipeline 1122, so as to facilitate the setting of the first throttle valve 114, and the second connecting pipe 1133 is used to realize the connection between the second heat exchange pipeline 1131 and the fourth heat exchange pipeline 1132, so as to facilitate the setting of the second throttle valve 115. The refrigerant after absorbing heat in the first heat exchange pipeline 1121 enters the first connecting pipe 1123, and after throttling, expansion and cooling through the first throttle valve 114 on the first connecting pipe 1123, enters the third heat exchange pipeline 1122. The refrigerant after absorbing heat in the second heat exchange pipeline 1131 enters the second connecting pipe 1133, and after throttling, expansion and cooling through the second throttle valve 115 on the second connecting pipe 1133, enters the fourth heat exchange pipeline 1132.

[0082] See also Figure 1 and Figure 3 In one embodiment, the first connecting pipe 1123, the second connecting pipe 1133, the first throttle valve 114 and the second throttle valve 115 are located outside the heat exchange body 111. That is, the first throttle valve 114 and the second throttle valve 115 perform throttling expansion and cooling outside the heat exchange body 111 to avoid releasing heat in the heat exchange body 111 when the refrigerant is cooled, thereby ensuring the liquefaction effect of natural gas.

[0083] The single-cycle mixed refrigerant natural gas liquefaction equipment 100 of the present application uses a refrigeration component 130 to achieve two-stage compression of the refrigerant, and the compressed gas refrigerant and liquid refrigerant are respectively transported to the first heat exchange component 112 and the second heat exchange component 113 of the heat exchange unit 110 to exchange heat with the gaseous natural gas in the liquefaction component 120 to output liquefied natural gas to achieve liquefaction of natural gas. In addition, the first throttle valve 114 and the second throttle valve 115 are used to cool and gasify the refrigerant in the first heat exchange component 112 and the second heat exchange component 113, respectively, to improve the heat exchange efficiency and liquefaction efficiency, and reduce the complexity of the liquefaction equipment and liquefaction process, which is easy to operate.

[0084] At the same time, a booster pump 137 is provided between the first gas-liquid separator 135 and the output port of the second compressor 132, and the liquid refrigerant outputted from the first gas-liquid separator 135 is transported to the output port of the second compressor 132 through the booster pump 137, and then transported to the second gas-liquid separator 136, so as to provide power for the circulation of the refrigerant in the refrigeration circuit. A booster pump 137 is used for pressurization, thereby reducing the number of moving equipment. In addition, the heat exchange body 111 adopts a coil heat exchanger to increase the single-line output. The single-cycle mixed refrigerant natural gas liquefaction equipment 100 has the characteristics of large single-line output, simple process, low energy consumption, and easy operation.

[0085] See also Figure 1 and Figure 4 , Figure 4 for Figure 1 The present application also provides a single-cycle mixed refrigerant natural gas liquefaction process, which is applied to the single-cycle mixed refrigerant natural gas liquefaction device 100 as in any of the above embodiments, and the single-cycle mixed refrigerant natural gas liquefaction process at least includes the following steps:

[0086] The low-pressure refrigerant outputted from the heat exchange body 111 enters the first compressor 131, is compressed by the first compressor 131, enters the first cooler 133 for condensation, and then enters the first gas-liquid separator 135;

[0087] The first gas-liquid separator 135 delivers the gas refrigerant to the second compressor 132 and delivers the liquid refrigerant to the output port of the second compressor 132;

[0088] The second compressor 132 compresses the gas refrigerant, mixes it with the liquid refrigerant delivered by the first gas-liquid separator 135, enters the second cooler 134 for condensation, and then enters the second gas-liquid separator 136;

[0089] The second gas-liquid separator 136 delivers the separated gas refrigerant to the first heat exchange component 112 and delivers the liquid refrigerant to the second heat exchange component 113;

[0090] When the gaseous natural gas is transported through the liquefaction assembly 120 , it can exchange heat with the refrigerant in the heat exchange body 111 , the first heat exchange component 112 , and the second heat exchange component 113 to output liquefied natural gas.

[0091] The high-temperature refrigerant after absorbing heat in the heat exchange body 111 enters the first compressor 131. After being compressed by the first compressor 131, the refrigerant is transported to the first cooler 133 for condensation. The condensed refrigerant enters the first gas-liquid separator 135, and the gas-liquid mixed refrigerant is separated by the first gas-liquid separator 135. The first gas-liquid separator 135 transports the gas refrigerant to the second compressor 132, and transports the liquid refrigerant to the output port of the second compressor 132. The second compressor 132 compresses the gas refrigerant and outputs it, and after mixing with the liquid refrigerant transported by the first gas-liquid separator 135, it enters the second cooler 134 for condensation. The condensed refrigerant enters the second gas-liquid separator 136, and the gas-liquid mixed refrigerant is separated by the second gas-liquid separator 136. The second gas-liquid separator 136 transports the gas refrigerant to the first heat exchange component 112, and transports the liquid refrigerant to the second heat exchange component 113. At this time, the first heat exchange component 112 exchanges heat with the gaseous natural gas in the liquefaction component 120 through the gas refrigerant, and the second heat exchange component 113 exchanges heat with the gaseous natural gas in the liquefaction component 120 through the liquid refrigerant, thereby liquefying the natural gas.

[0092] Moreover, after the first heat exchange component 112 and the second heat exchange component 113 exchange heat with the gaseous natural gas in the liquefied component 120, the first throttle valve 114 and the second throttle valve 115 can also reduce the temperature of the refrigerant absorbing heat in the first heat exchange component 112 and the second heat exchange component 113. Specifically, the first throttle valve 114 is provided in the first heat exchange component 112, and the second throttle valve 115 is provided in the second heat exchange component 113. The first throttle valve 114 can cause the refrigerant in the first heat exchange component 112 to throttle and expand to reduce the temperature of the refrigerant, and the second throttle valve 115 can cause the refrigerant in the second heat exchange component 113 to throttle and expand to reduce the temperature of the refrigerant. In this way, the refrigerants in the first heat exchange component 112 and the second heat exchange component 113 are both at a lower temperature, which can better exchange heat with the gaseous natural gas in the liquefied component 120, so that the liquefied component 120 outputs liquefied natural gas to achieve liquefaction of natural gas.

[0093] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0094] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A single-cycle mixed refrigerant natural gas liquefaction equipment, characterized in that: It includes a heat exchange unit, a liquefaction component and a refrigeration component; The refrigeration assembly includes a first compressor, a second compressor, a first cooler, a second cooler, a first gas-liquid separator, and a second gas-liquid separator, and the heat exchange unit, the first compressor, the first cooler, the first gas-liquid separator, the second compressor, the second cooler, and the second gas-liquid separator are connected in series to form a refrigeration circuit for the refrigerant to flow; The heat exchange unit comprises a heat exchange body, a first heat exchange component, a second heat exchange component, a first throttle valve and a second throttle valve, wherein the first heat exchange component and the second heat exchange component are arranged in the heat exchange body, the first throttle valve is arranged in the first heat exchange component, and the second throttle valve is arranged in the second heat exchange component, wherein the heat exchange body is a coiled heat exchanger; The second gas-liquid separator delivers the gas refrigerant to the first heat exchange component, and the second gas-liquid separator delivers the liquid refrigerant to the second heat exchange component; The liquefaction component exchanges heat with the refrigerant in the first heat exchange component and the second heat exchange component through the heat exchange body.

2. The single-cycle mixed refrigerant natural gas liquefaction equipment according to claim 1, characterized in that: The first heat exchange component includes a first heat exchange pipeline, and the second heat exchange component also includes a second heat exchange pipeline, and the first heat exchange pipeline and the second heat exchange pipeline are arranged on the heat exchange body along the vertical direction; The liquefaction component includes a liquefaction pipeline, a first pipe portion and a second pipe portion. The liquefaction pipeline is arranged in the heat exchange body and is arranged in parallel with the first heat exchange pipeline and the second heat exchange pipeline. The first pipe portion and the second pipe portion are arranged at both ends of the liquefaction pipeline.

3. The single-cycle mixed refrigerant natural gas liquefaction equipment according to claim 2, characterized in that: The inlet ends of the first heat exchange pipeline and the second heat exchange pipeline are located at the bottom of the heat exchange body, and the refrigerant flows from bottom to top in the first heat exchange pipeline and the second heat exchange pipeline.

4. The single-cycle mixed refrigerant natural gas liquefaction equipment according to claim 2, characterized in that: The first heat exchange component also includes a third heat exchange pipeline, and the second heat exchange component also includes a fourth heat exchange pipeline, the third heat exchange pipeline is connected to the first heat exchange pipeline, the first throttle valve is arranged between the third heat exchange pipeline and the first heat exchange pipeline, the fourth heat exchange pipeline is connected to the second heat exchange pipeline, and the second throttle valve is arranged between the fourth heat exchange pipeline and the second heat exchange pipeline.

5. The single-cycle mixed refrigerant natural gas liquefaction equipment according to claim 4, characterized in that: The first heat exchange component further includes a first connecting pipe, and the second heat exchange component further includes a second connecting pipe; The first connecting pipe connects the first heat exchange pipeline and the third heat exchange pipeline, and the second connecting pipe connects the second heat exchange pipeline and the fourth heat exchange pipeline; The first throttle valve is disposed on the first connecting pipe, and the second throttle valve is disposed on the second connecting pipe.

6. The single-cycle mixed refrigerant natural gas liquefaction equipment according to claim 5, characterized in that: The first connecting pipe, the second connecting pipe, the first throttle valve and the second throttle valve are located outside the heat exchange body.

7. The single-cycle mixed refrigerant natural gas liquefaction equipment according to claim 5, characterized in that: The third heat exchange pipeline and the fourth heat exchange pipeline are spray pipes and extend in the horizontal direction, and the third heat exchange pipeline is located at the top of the heat exchange body, and the fourth heat exchange pipeline is located in the middle of the heat exchange body; Alternatively, the third heat exchange pipeline and the fourth heat exchange pipeline are heat exchange coils or heat exchange straight pipes.

8. The single-cycle mixed refrigerant natural gas liquefaction equipment according to any one of claims 1 to 7, characterized in that: The first gas-liquid separator has a first gas outlet pipe and a first liquid outlet pipe, the first gas outlet pipe is connected to the second compressor, the first liquid outlet pipe is connected to the output port of the second compressor and is connected to the second cooler; And / or, the second gas-liquid separator has a second gas outlet pipe and a second liquid outlet pipe, the second gas outlet pipe is connected to the first heat exchange component, and the second liquid outlet pipe is connected to the second heat exchange component.

9. The single-cycle mixed refrigerant natural gas liquefaction equipment according to any one of claims 1 to 7, characterized in that: The refrigeration assembly further includes a third gas-liquid separator, which is disposed between the heat exchange body and the first compressor; And / or, the refrigeration assembly further includes a booster pump, and the booster pump is arranged between the first liquid outlet pipe of the first gas-liquid separator and the second cooler.

10. The single-cycle mixed refrigerant natural gas liquefaction equipment according to any one of claims 1 to 7, characterized in that: The refrigeration assembly further includes a driving member, and the driving member is connected to the first compressor and the second compressor at the same time.

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