Heat recovery device and methanol synthesis system
By designing a heat recovery device in the methanol synthesis system, using the heat exchange between high-temperature process gas and pre-tower kettle liquid, the problem of unused heat in the methanol synthesis process is solved, and energy consumption is reduced and operating costs is optimized.
Patent Information
- Application Number
- CN202420561320.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-22
- Publication Date
- 2025-03-14
- Estimated Expiration
- 2034-03-22
AI Technical Summary
In the methanol synthesis process, the heat of the high-temperature process gas cannot be effectively utilized, resulting in a large energy consumption of air coolers and water coolers, increasing the operating cost of the methanol synthesis system.
A heat recovery device is designed, including a pre-tower and a first heat exchanger. The high-temperature process gas and the pre-tower kettle liquid are heat exchanged in the first heat exchanger, the heat in the process gas is recovered, and the heat utilization is further optimized through a multi-stage heat exchanger.
The heat of high-temperature process gas in the methanol synthesis process is effectively recovered, the operating energy consumption of pre-tower and air cooler is reduced, and the overall energy consumption and operating cost of the methanol synthesis system is reduced.
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Figure CN222613221U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of energy-saving technology, and in particular to a heat recovery device and a methanol synthesis system. Background Art
[0002] At present, the world's methanol production mainly adopts the low-pressure method with a pressure of 5-10MPa, and the low-pressure method is the mainstream of the development of large-scale methanol industrial equipment. Various methanol process are similar, and the main difference lies in the design of the reactor, the removal of reaction heat and the different recycling methods. The main process flow of Casali methanol synthesis is: the fresh gas with a pressure of 5.21MPa and a temperature of 30℃ from the low-temperature methanol washing process is mixed with the hydrogen-rich gas from the hydrogen recovery unit and enters the fresh section of the synthesis gas compressor. The fresh gas with a pressure of 8.94MPa and a temperature of 98.8℃ after being pressurized is mixed with the gas with a pressure of 8.84MPa and a temperature of 63.9℃ from the circulation section of the synthesis gas compressor and enters the inlet and outlet heat exchangers, and exchanges heat with the outlet gas of the synthesis tower. The mixed gas is heated to 210℃ and then enters the synthesis tower for methanol synthesis reaction. The process gas from the methanol synthesis tower enters the inlet and outlet heat exchangers to exchange heat with the inlet gas of the synthesis tower. The outlet process gas is cooled to 120°C, and then cooled to about 60°C by the air cooler. The gas-liquid mixture enters the water cooler. The gas is further cooled to 40°C. Most of the methanol in the gas is condensed, and the gas-liquid mixture is separated in the methanol high-pressure separator. Most of the separated gas is sent to the inlet of the synthesis gas compressor circulation section, and a small part is sent to the hydrogen recovery device after washing in the purge gas washing tower to optimize the carbon-hydrogen ratio at the inlet of the synthesis tower. The liquid methanol coming out of the methanol high-pressure separator is decompressed to 0.45MPa in the flash tank and sent to the distillation or tank area as crude methanol at 40°C.
[0003] However, the process gas in this methanol synthesis process needs to be cooled from high temperature to low temperature. The heat of the high-temperature process gas cannot be utilized in this process. In addition, the air cooler and water cooler consume a lot of energy in the operation of the methanol synthesis system, resulting in waste heat waste, which increases the operating cost of the methanol synthesis system to a certain extent. Utility Model Content
[0004] In order to solve the above technical problems or at least partially solve the above technical problems, the present application provides a heat recovery device and a methanol synthesis system to recover and reuse part of the heat in the methanol synthesis process so as to reduce the operating energy consumption of the methanol synthesis system.
[0005] In a first aspect, an embodiment of the present application provides a heat recovery device for a methanol synthesis device, the heat recovery device comprising a pre-tower and a first heat exchanger, the pre-tower having a liquid inlet and a liquid outlet;
[0006] The first heat exchanger has a high-temperature air inlet, a low-temperature air outlet, a low-temperature liquid inlet and a high-temperature liquid outlet, wherein the high-temperature air inlet is used to receive high-temperature process gas, the low-temperature air outlet is used to output low-temperature process gas, the low-temperature liquid inlet is connected to the liquid outlet of the pre-tower through a first pipeline, and the high-temperature liquid outlet is connected to the liquid inlet of the pre-tower through a second pipeline.
[0007] In some embodiments, the heat recovery device further comprises:
[0008] The second heat exchanger, the output port of the second heat exchanger is connected to the liquid inlet of the pre-tower, and the input port of the second heat exchanger is connected to the liquid outlet of the pre-tower, for realizing heat exchange between steam condensate and pre-tower bottom liquid.
[0009] In some embodiments, the heat recovery device further comprises:
[0010] The third heat exchanger, the output port of the third heat exchanger is connected to the liquid inlet of the pre-tower, and the input port of the third heat exchanger is connected to the liquid outlet of the pre-tower, for realizing heat exchange between low-pressure steam and pre-tower bottom liquid.
[0011] In some embodiments, the first heat exchanger, the second heat exchanger, and the third heat exchanger are shell and tube heat exchangers.
[0012] In the second aspect, an embodiment of the present application provides a methanol synthesis system, which includes a heat recovery device and an inlet and outlet heat exchanger, and the heat recovery device is a heat recovery device described in any one of the above items; the process gas output port of the inlet and outlet heat exchanger is connected to the high-temperature air inlet of the first heat exchanger.
[0013] In some embodiments, the methanol synthesis system further comprises:
[0014] A synthesis tower, wherein the process gas output port of the synthesis tower is connected to the process gas input port of the inlet and outlet heat exchanger;
[0015] The inlet gas input port of the synthesis tower is communicated with the inlet gas output port of the inlet and outlet heat exchanger, and the inlet gas and the process gas are heat exchanged in the inlet and outlet heat exchanger.
[0016] In some embodiments, the inlet gas input port of the synthesis tower is connected to the gas outlet of a synthesis compressor, and the synthesis compressor is used to generate the inlet gas.
[0017] In some embodiments, the methanol synthesis system further comprises:
[0018] An air cooler, wherein the low-temperature process gas inlet of the air cooler is connected to the low-temperature gas outlet of the first heat exchanger.
[0019] In some embodiments, the methanol synthesis system further comprises:
[0020] A water cooler, wherein the product inlet of the water cooler is connected to the low-temperature process gas outlet of the air cooler.
[0021] In some embodiments, the inlet and outlet heat exchangers are shell and tube heat exchangers.
[0022] Beneficial effects of the present application: Different from the prior art, the heat recovery device and methanol synthesis system provided by the embodiments of the present application; wherein, the heat recovery device includes a pre-tower and a first heat exchanger, the pre-tower having a liquid inlet and a liquid outlet; the first heat exchanger having a high-temperature air inlet, a low-temperature air outlet, a low-temperature liquid inlet and a high-temperature liquid outlet, wherein the high-temperature air inlet is used to receive high-temperature process gas, the low-temperature air outlet is used to output low-temperature process gas, the low-temperature liquid inlet is connected to the liquid outlet of the pre-tower through a first pipeline, and the high-temperature liquid outlet is connected to the liquid inlet of the pre-tower through a second pipeline. Through the above design, the high-temperature process gas and the pre-tower bottom liquid are heat exchanged in the first heat exchanger, so that the excess heat of the process gas is transferred to the pre-tower bottom liquid, realizing the recovery and utilization of the waste heat of the high-temperature process gas and reducing the operating energy consumption of the pre-tower. The methanol synthesis system provided in the embodiment of the present application includes the above-mentioned heat recovery device, inlet and outlet heat exchangers, a synthesis tower, an air cooler and a water cooler. The high-temperature process gas exiting the synthesis tower is cooled step by step through the inlet and outlet heat exchangers, the first heat exchanger, the air cooler and the water cooler, thereby achieving full utilization of the thermal energy in the process gas; among them, the first heat exchanger effectively reduces the process gas temperature at the inlet of the air cooler, thereby reducing the operating energy consumption of the air cooler, and achieving the purpose of reducing the operating energy consumption and operating cost of the methanol synthesis system. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.
[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0025] Figure 1 is a schematic structural diagram of a heat recovery device provided in an embodiment of the present application;
[0026] Figure 2 is a structural schematic diagram of a heat recovery device provided in another embodiment of the present application;
[0027] Figure 3 It is a schematic diagram of the structure of the methanol synthesis system provided in the embodiment of the present application.
[0028] Figure numerals: heat recovery device 100, pre-tower 110, first heat exchanger 120, liquid inlet 111, liquid outlet 112, high-temperature air inlet 121, low-temperature air inlet 122, low-temperature liquid inlet 123, high-temperature liquid outlet 124, first pipeline 101, second pipeline 102, second heat exchanger 130, third heat exchanger 140, methanol synthesis system 200, inlet and outlet heat exchangers 210, synthesis tower 220, air cooler 230. DETAILED DESCRIPTION
[0029] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0030] In the following description, for the purpose of explanation rather than limitation, specific details such as specific system structures, interfaces, and technologies are provided to facilitate a thorough understanding of the present application.
[0031] The terms "first", "second", and "third" in this application are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second", and "third" can explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. All directional indications in the embodiments of this application (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. The terms "including" and "having" in the embodiments of this application and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or components inherent to these processes, methods, products, or devices.
[0032] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.
[0033] The present application is described in detail below with reference to the accompanying drawings and embodiments.
[0034] See also Figure 1 , Figure 1 It is a schematic diagram of the structure of the heat recovery device provided in the embodiment of the present application.
[0035] An embodiment of the present application provides a heat recovery device 100 for a methanol synthesis device. The heat recovery device 100 includes a pre-tower 110 and a first heat exchanger 120. The pre-tower 110 has a liquid inlet 111 and a liquid outlet 112; the first heat exchanger 120 has a high-temperature air inlet 121, a low-temperature air outlet 122, a low-temperature liquid inlet 123 and a high-temperature liquid outlet 124.
[0036] Specifically, the high-temperature air inlet 121 is used to receive high-temperature process gas, the low-temperature air outlet 122 is used to output low-temperature process gas, the low-temperature liquid inlet 123 is connected to the liquid outlet 112 of the pre-tower 110 through the first pipeline 101, and the high-temperature liquid outlet 124 is connected to the liquid inlet 111 of the pre-tower 110 through the second pipeline 102.
[0037] The high-temperature process gas enters the first heat exchanger 120 from the high-temperature gas inlet 121, and the low-temperature pre-tower bottom liquid flows out from the liquid outlet 112 and enters the first heat exchanger 120 from the low-temperature liquid inlet 123 through the first pipeline 101. The low-temperature pre-tower bottom liquid and the high-temperature process gas are heat-exchanged in the first heat exchanger 120 to obtain low-temperature process gas and high-temperature pre-tower bottom liquid. The low-temperature process gas flows out from the low-temperature gas outlet 122 of the first heat exchanger 120 and is transmitted to the next process; the high-temperature pre-tower bottom liquid flows out from the high-temperature liquid outlet 124 and enters the pre-tower 110 from the liquid inlet 111 through the second pipeline 102. Since there is a certain temperature difference between the temperature of the high-temperature process gas entering the first heat exchanger 120 and the temperature of the pre-tower bottom liquid, the high-temperature process gas and the pre-tower bottom liquid can be fully utilized for heat exchange, and part of the heat of the high-temperature process gas can be recovered, thereby reducing the steam consumption of the pre-tower distillation methanol and reducing the system operation cost.
[0038] In one embodiment, the temperature of the high-temperature process gas may be 120°C, and the temperature of the low-temperature pre-tower bottom liquid may be 78°C.
[0039] In one embodiment, the first heat exchanger 120 may include but is not limited to a shell and tube heat exchanger; illustratively, the first heat exchanger may be a syngas or methanol heat exchanger.
[0040] See also Figure 2 , Figure 2 This is a heat recovery device provided in another embodiment of the present application.
[0041] Another embodiment of the present application provides a heat recovery device 100 including a pre-tower 110, a first heat exchanger 120, a second heat exchanger 130 and a third heat exchanger 140. The pre-tower 100 and the first heat exchanger 120 are the pre-tower 100 and the first heat exchanger 120 described in the above embodiment, so the same parts are not repeated.
[0042] Specifically, the output port (not marked in the figure) of the second heat exchanger 130 is connected to the liquid inlet 111 of the pre-tower 110, and the input port (not marked in the figure) of the second heat exchanger 130 is connected to the liquid outlet 112 of the pre-tower 110, so as to realize heat exchange between steam condensate and pre-tower bottom liquid. The output port (not marked in the figure) of the third heat exchanger 140 is connected to the liquid inlet 111 of the pre-tower 110, and the input port (not marked in the figure) of the third heat exchanger 140 is connected to the liquid outlet 112 of the pre-tower 110, so as to realize heat exchange between low-pressure steam and pre-tower bottom liquid.
[0043] In some embodiments, a condensate reboiler (not shown) and a steam reboiler (not shown) provide heat sources for the pre-tower 110. Specifically, the condensate reboiler is cyclically connected to the second heat exchanger 130, and the steam reboiler is cyclically connected to the third heat exchanger 140; the condensate reboiler uses steam condensate from the pressurized tower reboiler to provide heat, and the steam reboiler uses 0.5 MPa saturated steam to provide heat.
[0044] In some embodiments, the first heat exchanger 120, the second heat exchanger 130, and the third heat exchanger 140 may include, but are not limited to, shell and tube heat exchangers; illustratively, the first heat exchanger may be a syngas / methanol heat exchanger.
[0045] See also Figure 3 , Figure 3 It is a schematic diagram of the structure of the methanol synthesis system provided in the embodiment of the present application.
[0046] The embodiment of the present application provides a methanol synthesis system 200. The methanol synthesis system 200 includes a heat recovery device 100, an inlet and outlet heat exchanger 210, a synthesis tower 220 and an air cooler 230. The heat recovery device 100 is the heat recovery device 100 described in any of the above embodiments, so the same parts are not repeated.
[0047] In some embodiments, the process gas output port (not marked in the figure) of the synthesis tower 220 is connected to the process gas input port (not marked in the figure) of the inlet and outlet heat exchanger 210; the process gas output port (not marked in the figure) of the inlet and outlet heat exchanger 210 is connected to the high-temperature air inlet 121 of the first heat exchanger 120; the inlet gas input port of the synthesis tower 220 is connected to the inlet gas output port of the inlet and outlet heat exchanger 210, and the inlet gas and the process gas are heat exchanged in the inlet and outlet heat exchanger 210.
[0048] In some embodiments, the inlet gas input port of the synthesis tower 220 is connected to the gas outlet of a synthesis compressor (not shown), and the synthesis compressor is used to generate the inlet gas.
[0049] In some embodiments, the low-temperature process gas inlet of the air cooler 230 is in communication with the low-temperature gas outlet 122 of the first heat exchanger 120 .
[0050] In some embodiments, a water cooler (not shown) is used, and a product inlet of the water cooler is connected to a low-temperature process gas outlet of the air cooler 230 .
[0051] Exemplarily, the inlet and outlet heat exchangers 210 may include, but are not limited to, shell and tube heat exchangers, and the first heat exchanger may be a synthesis gas heat exchanger or a methanol heat exchanger.
[0052] Specifically, fresh gas with a pressure of 5.21 MPa and a temperature of 30°C is mixed with hydrogen-rich gas from the hydrogen recovery unit and enters the fresh section of the synthesis compressor. After the gas is pressurized, the new fresh gas with a pressure of 8.94 MPa and a temperature of 98.8°C is mixed with the gas with a pressure of 8.84 MPa and a temperature of 63.9°C from the circulation section of the synthesis compressor to generate the inlet gas. The inlet gas enters the inlet and outlet heat exchangers 210 and exchanges heat with the outlet gas of the synthesis tower 220. The mixed gas is heated to 210°C and then enters the synthesis tower 220 for methanol synthesis reaction. The process gas exiting the synthesis tower 220 enters the inlet and outlet heat exchangers 220 to exchange heat with the inlet gas of the synthesis tower 220. The outlet process gas is cooled to 120°C, and the high-temperature process gas at 120°C enters the first heat exchanger 120 to exchange heat with the low-temperature pre-tower bottom liquid; the low-temperature pre-tower bottom liquid flows out from the liquid outlet 112 and enters the first heat exchanger 120 from the low-temperature liquid inlet through the first pipeline 101. The low-temperature pre-tower bottom liquid and the high-temperature process gas are heat-exchanged in the first heat exchanger 120 to obtain low-temperature process gas and high-temperature pre-tower bottom liquid. The low-temperature process gas flows out through the low-temperature gas outlet 122 of the first heat exchanger 120 and is transmitted to the next process; the high-temperature pre-tower bottom liquid flows out from the high-temperature liquid outlet 124 and is input into the pre-tower 110 from the liquid inlet 111 through the second pipeline 102. Since there is a certain temperature difference between the temperature of the high-temperature process gas entering the first heat exchanger 120 and the temperature of the pre-tower bottom liquid, the high-temperature process gas can be fully utilized for heat exchange with the pre-tower bottom liquid, and part of the heat of the high-temperature process gas can be recovered, thereby reducing the steam consumption of the pre-tower distillation methanol and reducing the system operation cost of the pre-tower distillation methanol process. After the low-temperature process gas is cooled by the first heat exchanger 120, it is cooled to about 60°C by the air cooler 230, and the gas-liquid mixture enters the water cooler. The process gas is further cooled to 40°C, and most of the methanol in the process gas is condensed. The process gas-liquid mixture is separated in the methanol high-pressure separator. Most of the separated gas is sent to the inlet of the circulation section of the synthesis gas compressor, and a small part is sent to the hydrogen recovery device after washing in the purge gas washing tower to optimize the carbon-hydrogen ratio at the inlet of the synthesis tower 220. The liquid methanol coming out of the methanol high-pressure separator is decompressed to 0.45MPa in the flash tank and sent to the distillation or tank area as crude methanol at 40°C. It should be noted that since the temperature of the process gas at the low-temperature process gas inlet of the air cooler 230 is cooled by the first heat exchanger 120, the temperature that needs to be cooled by the air cooler 230 is reduced, thereby reducing the energy consumption of the air cooler 230 in the methanol synthesis system 200, reducing resource waste, and reducing the process cost of methanol synthesis.
[0053] In summary, the heat recovery device and methanol synthesis system provided by the embodiment of the present application; wherein, the heat recovery device includes a pre-tower and a first heat exchanger, the pre-tower having a liquid inlet and a liquid outlet; the first heat exchanger having a high-temperature air inlet, a low-temperature air outlet, a low-temperature liquid inlet and a high-temperature liquid outlet, wherein the high-temperature air inlet is used to receive high-temperature process gas, the low-temperature air outlet is used to output low-temperature process gas, the low-temperature liquid inlet is connected to the liquid outlet of the pre-tower through a first pipeline, and the high-temperature liquid outlet is connected to the liquid inlet of the pre-tower through a second pipeline. Through the above design, the high-temperature process gas and the pre-tower bottom liquid are heat exchanged in the first heat exchanger, so that the excess heat of the process gas is transferred to the pre-tower bottom liquid, realizing the recovery and utilization of the waste heat of the high-temperature process gas, and reducing the operating energy consumption of the pre-tower and the operating cost of the methanol distillation system. The methanol synthesis system provided in the embodiment of the present application includes the above-mentioned heat recovery device, inlet and outlet heat exchangers, a synthesis tower, an air cooler and a water cooler. The high-temperature process gas exiting the synthesis tower is cooled step by step through the inlet and outlet heat exchangers, the first heat exchanger, the air cooler and the water cooler, thereby achieving full utilization of the thermal energy in the process gas; among them, the first heat exchanger effectively reduces the process gas temperature at the inlet of the air cooler, thereby reducing the operating energy consumption of the air cooler, and achieving the purpose of reducing the operating energy consumption and operating cost of the methanol synthesis system.
[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.
Claims
1. A heat recovery device for a methanol synthesis device, characterized in that: include: A pre-tower having a liquid inlet and a liquid outlet; The first heat exchanger has a high-temperature air inlet, a low-temperature air outlet, a low-temperature liquid inlet and a high-temperature liquid outlet, wherein the high-temperature air inlet is used to receive high-temperature process gas, the low-temperature air outlet is used to output low-temperature process gas, the low-temperature liquid inlet is connected to the liquid outlet of the pre-tower through a first pipeline, and the high-temperature liquid outlet is connected to the liquid inlet of the pre-tower through a second pipeline.
2. The heat recovery device according to claim 1, characterized in that: The heat recovery device also includes: The second heat exchanger, the output port of the second heat exchanger is connected to the liquid inlet of the pre-tower, and the input port of the second heat exchanger is connected to the liquid outlet of the pre-tower, for realizing heat exchange between steam condensate and pre-tower bottom liquid.
3. The heat recovery device according to claim 2, characterized in that: The heat recovery device also includes: The third heat exchanger, the output port of the third heat exchanger is connected to the liquid inlet of the pre-tower, and the input port of the third heat exchanger is connected to the liquid outlet of the pre-tower, for realizing heat exchange between low-pressure steam and pre-tower bottom liquid.
4. The heat recovery device according to any one of claims 1 to 3, characterized in that: The heat exchanger is a shell and tube heat exchanger.
5. A methanol synthesis system, characterized in that: include: A heat recovery device and an inlet and outlet heat exchanger, wherein the heat recovery device is the heat recovery device according to any one of claims 1 to 3; the process gas output port of the inlet and outlet heat exchanger is connected to the high-temperature air inlet of the first heat exchanger.
6. The methanol synthesis system according to claim 5, characterized in that: The methanol synthesis system also includes: A synthesis tower, wherein the process gas output port of the synthesis tower is connected to the process gas input port of the inlet and outlet heat exchanger; The inlet gas input port of the synthesis tower is connected to the inlet gas output port of the inlet and outlet heat exchanger, and the inlet gas and the process gas are heat exchanged in the inlet and outlet heat exchanger.
7. The methanol synthesis system according to claim 6, characterized in that: The inlet gas input port of the synthesis tower is connected to the gas outlet of the synthesis compressor, and the synthesis compressor is used to generate the inlet gas.
8. The methanol synthesis system according to claim 5, characterized in that: The methanol synthesis system also includes: An air cooler, wherein the low-temperature process gas inlet of the air cooler is connected to the low-temperature gas outlet of the first heat exchanger.
9. The methanol synthesis system according to claim 8, characterized in that: The methanol synthesis system also includes: A water cooler, wherein the product inlet of the water cooler is connected to the low-temperature process gas outlet of the air cooler.
10. The methanol synthesis system according to claim 5, characterized in that: The inlet and outlet heat exchangers are shell and tube heat exchangers.