Gas dehydration system and method

Abstract

The invention discloses a gas dehydration system and method. The system comprises a dehydration device, a triethylene glycol regeneration system and an absorption type heating pump device, the dehydration device, the triethylene glycol regeneration system and the absorption type heating pump device are connected to form a triethylene glycol circulation loop; the triethylene glycol dehydration regeneration system is connected with the absorption type heating pump device to form a first heat-conducting substance circulation loop; or the system comprises a molecular sieve absorption device, a molecular sieve regeneration system, a gas-liquid separation system and an absorption type heating pump device; the molecular sieve absorption device, the molecular sieve regeneration system, the absorption type heating pump device and the gas-liquid separation system are connected to form a dry gas circulation loop; and the molecular sieve regeneration system is connected with the absorption type heating pump device to form a second closed loop of the heat-conducting substance. And the energy consumption in the gas dehydration process can be saved.

Description

Technical Field

[0001] The present invention relates to the field of carbon dioxide capture, utilization and storage, and particularly to a gas dehydration system and method. Background Art

[0002] Carbon capture, utilization and storage technology is a technology for realizing large-scale low-carbon utilization of fossil energy. As an important means to reduce CO2 emissions and achieve sustainable development, it has received increasing attention. In carbon capture, utilization and storage technology, before CO2 enters the long-distance pipeline, it needs to be deeply dehydrated to prevent the precipitation of free water in the downstream pipeline from forming highly corrosive carbonic acid.

[0003] The prior art mainly uses molecular sieve adsorption method and triethylene glycol absorption method to achieve deep dehydration of CO2. Among them, the molecular sieve adsorption method uses the adsorption force on the surface of the solid adsorbent to achieve dehydration. When the molecular sieve absorption tower enters the regeneration stage, the adsorbent is heated, and the absorbed water is separated from the solid adsorbent. Adsorption and desorption are repeated to achieve deep dehydration of CO2; the triethylene glycol absorption method uses the hydrophilicity of the glycol absorbent to counter-currently contact with CO2, and the water in CO2 is removed through absorption in the absorption tower. After the triethylene glycol rich solution absorbed with water is heated, the water is separated through fractionation. The dehydrated triethylene glycol lean solution is cooled and then recycled into the absorption tower again; however, both of these two methods have a high-temperature heating process in the regeneration stage and a cooling process after regeneration, and the energy consumption is relatively high. Therefore, it is very necessary to provide a molecular sieve regeneration device or a triethylene glycol regeneration device that saves energy. Summary of the Invention

[0004] In view of the above problems, the present invention is proposed to provide a gas dehydration system and method that overcome the above problems or at least partially solve the above problems.

[0005] In a first aspect, an embodiment of the present invention provides a gas dehydration system, including a dehydration device, a triethylene glycol regeneration system, and an absorption heat pump device:

[0006] The dehydration device, the triethylene glycol regeneration system, and the absorption heat pump device are connected to form a triethylene glycol circulation loop;

[0007] The triethylene glycol dehydration and regeneration system is connected to the absorption heat pump device to form a first circulation loop of the heat-conducting substance;

[0008] The triethylene glycol dehydration and regeneration system is used to receive the triethylene glycol rich solution and perform heat treatment on the received triethylene glycol rich solution to obtain the regenerated triethylene glycol lean solution; the absorption heat pump device is used to receive the regenerated triethylene glycol lean solution and perform temperature reduction treatment on the received regenerated triethylene glycol lean solution; the dehydration device is used to receive the cooled regenerated triethylene glycol lean solution and generate the triethylene glycol rich solution;

[0009] The triethylene glycol dehydration and regeneration system is further configured to receive a first heat-conducting substance, and heat the received rich triethylene glycol solution with the first heat-conducting substance to obtain a second heat-conducting substance; the absorption heat pump device is further configured to receive the second heat-conducting substance and heat the received second heat-conducting substance to obtain the first heat-conducting substance, and the temperature of the first heat-conducting substance is higher than that of the second heat-conducting substance.

[0010] In one embodiment, the triethylene glycol regeneration system includes a triethylene glycol regeneration device and a lean liquid pump;

[0011] The triethylene glycol regeneration device is respectively connected to one end of the lean liquid pump and the dehydration device; the triethylene glycol regeneration device is configured to receive rich triethylene glycol solution and perform a heating treatment on the received rich triethylene glycol solution to obtain regenerated lean triethylene glycol solution;

[0012] The other end of the lean liquid pump is connected to the absorption heat pump device; the lean liquid pump is configured to transport the regenerated lean triethylene glycol solution to the absorption heat pump device.

[0013] In one embodiment, the absorption heat pump device includes an evaporator;

[0014] The evaporator is configured to receive one path of regenerated lean triethylene glycol solution and perform a temperature reduction treatment on the received regenerated lean triethylene glycol solution.

[0015] In one embodiment, the absorption heat pump device includes a generator;

[0016] The generator is configured to receive another path of regenerated lean triethylene glycol solution and perform a temperature reduction treatment on the received regenerated lean triethylene glycol solution.

[0017] In one embodiment, the absorption heat pump device further includes an absorber;

[0018] The absorber is connected to the triethylene glycol regeneration device; the absorber is configured to receive the second heat-conducting substance, and is further configured to release heat and perform a heating treatment on the received second heat-conducting substance to obtain the first heat-conducting substance; the triethylene glycol regeneration device is further configured to receive the first heat-conducting substance and perform a heating treatment on the rich triethylene glycol solution with the received first heat-conducting substance to obtain the second heat-conducting substance.

[0019] In a second aspect, an embodiment of the present invention provides a gas dehydration system, including: a molecular sieve absorption device, a molecular sieve regeneration system, a gas-liquid separation system, and an absorption heat pump device;

[0020] The molecular sieve absorption device, the molecular sieve regeneration system, the absorption heat pump device, and the gas-liquid separation system are connected to form a dry gas circulation loop;

[0021] The molecular sieve regeneration system is connected to the absorption heat pump device to form a second closed loop of the heat transfer medium;

[0022] The molecular sieve regeneration system is used to receive dry gas, heat the received dry gas, and regenerate the molecular sieve with the heated dry gas to generate wet gas; the absorption heat pump device is used to receive the wet gas and cool the received wet gas; the gas-liquid separation system is used to receive the cooled wet gas and perform cooling and gas-liquid separation processing on the cooled wet gas; the molecular sieve absorption device is used to receive the wet gas after gas-liquid separation and dry the received wet gas to obtain regenerated dry gas, and the regenerated dry gas circulates into the molecular sieve regeneration system;

[0023] The molecular sieve regeneration system is also used to receive a third heat transfer medium and heat the received dry gas with the received heat transfer medium to obtain a fourth heat transfer medium; the absorption heat pump device is used to receive the fourth heat transfer medium and heat the received fourth heat transfer medium to obtain a third heat transfer medium, and the temperature of the third heat transfer medium is higher than that of the fourth heat transfer medium.

[0024] In one embodiment, the molecular sieve regeneration system includes a heater and a molecular sieve regeneration device;

[0025] One end of the heater is connected to the molecular sieve absorption device, and the heater is used to receive dry gas and heat the received dry gas;

[0026] The molecular sieve regeneration device is respectively connected to the other end of the heater and the absorption heat pump device, and the molecular sieve regeneration device is used to receive the heated dry gas and regenerate the molecular sieve to generate wet gas.

[0027] In one embodiment, the absorption heat pump device includes an evaporator;

[0028] The evaporator is used to receive a stream of wet gas and cool the received wet gas.

[0029] In one embodiment, the absorption heat pump device includes a generator;

[0030] The generator is used to receive another stream of wet gas and cool the received wet gas.

[0031] In one embodiment, the absorption heat pump device further includes an absorber;

[0032] The absorber is connected to the heater. The absorber is used to receive the fourth heat transfer medium and also used to release heat to heat the received fourth heat transfer medium to obtain a third heat transfer medium; the heater is also used to receive the third heat transfer medium and heat the received dry gas with the third heat transfer medium to obtain a fourth heat transfer medium.

[0033] In a third aspect, an embodiment of the present invention provides a gas dehydration method, which is implemented by the aforementioned gas dehydration system and includes:

[0034] The triethylene glycol dehydration and regeneration system is used to receive the rich triethylene glycol solution and heat the received rich triethylene glycol solution to obtain the regenerated lean triethylene glycol solution; the absorption heat pump device is used to receive the regenerated lean triethylene glycol solution and cool the received regenerated lean triethylene glycol solution; the dehydration device is used to receive the cooled regenerated lean triethylene glycol solution and generate the rich triethylene glycol solution;

[0035] The triethylene glycol dehydration and regeneration system is further used to receive the first heat-conducting substance and heat the received rich triethylene glycol solution with the first heat-conducting substance to obtain the second heat-conducting substance; the absorption heat pump device is further used to receive the second heat-conducting substance and heat the received second heat-conducting substance to obtain the first heat-conducting substance, and the temperature of the first heat-conducting substance is higher than that of the second heat-conducting substance.

[0036] In a fourth aspect, an embodiment of the present invention provides a gas dehydration method, which is implemented by the aforementioned gas dehydration system and includes:

[0037] The molecular sieve regeneration system is used to receive the dry gas and heat the received dry gas, and regenerate the molecular sieve with the heated dry gas to generate the wet gas; the absorption heat pump device is used to receive the wet gas and cool the received wet gas; the gas-liquid separation system is used to receive the cooled wet gas and perform cooling and gas-liquid separation processing on the cooled wet gas; the molecular sieve absorption device is used to receive the wet gas after gas-liquid separation and dry the received wet gas to obtain the regenerated dry gas, and the regenerated dry gas circulates into the molecular sieve regeneration system;

[0038] The molecular sieve regeneration system is further used to receive the third heat-conducting substance and heat the received dry gas with the received heat-conducting substance to obtain the fourth heat-conducting substance; the absorption heat pump device is used to receive the fourth heat-conducting substance and heat the received fourth heat-conducting substance to obtain the third heat-conducting substance, and the temperature of the third heat-conducting substance is higher than that of the fourth heat-conducting substance.

[0039] The beneficial effects of the above technical solutions provided by the embodiments of the present invention at least include:

[0040] The gas dehydration system provided by the embodiments of the present invention includes a dehydration device, a triethylene glycol regeneration system, and an absorption heat pump device; the dehydration device, the triethylene glycol regeneration system, and the absorption heat pump device are connected to form a triethylene glycol circulation loop, wherein the triethylene glycol dehydration and regeneration system is used to receive the rich triethylene glycol solution and heat the received rich triethylene glycol solution to obtain the regenerated lean triethylene glycol solution; the absorption heat pump device is used to receive the regenerated lean triethylene glycol solution and absorb the heat of the regenerated lean triethylene glycol solution, so that the temperature of the regenerated lean triethylene glycol solution decreases; the dehydration device is used to receive the cooled regenerated lean triethylene glycol solution and generate the rich triethylene glycol solution. In addition, the absorption heat pump device is also used to receive a second heat-conducting substance and heat the received second heat-conducting substance to obtain a first heat-conducting substance with a temperature higher than that of the second heat-conducting substance, and the triethylene glycol dehydration and regeneration system is used to receive the first heat-conducting substance; the triethylene glycol dehydration and regeneration is realized for recycling; in the process of triethylene glycol dehydration, an absorption heat pump is introduced, and the medium-low grade heat source after triethylene glycol regeneration is used as the driving force. By using the heat potential difference between the medium-temperature heat source and the low-temperature heat source, heat higher than the medium-temperature heat source is produced, part of the medium-low heat energy is transferred to a higher temperature level, the utilization grade of the heat energy is improved, and the heating energy consumption in the process of triethylene glycol dehydration and regeneration is saved.

[0041] The gas dehydration system provided by the embodiments of the present invention includes a molecular sieve absorption device, a molecular sieve regeneration system, a gas-liquid separation system, and an absorption heat pump device; the molecular sieve absorption device, the molecular sieve regeneration system, the absorption heat pump device, and the gas-liquid separation system are connected to form a dry gas circulation loop; the molecular sieve regeneration system is used to receive dry gas and heat the dry gas to realize the regeneration of the molecular sieve through the heated dry gas. After the molecular sieve is regenerated, the dry gas turns into wet gas. The absorption heat pump device is used to receive the wet gas, and the wet gas exchanges heat in the absorption heat pump device and the temperature decreases. The gas-liquid separation system receives the cooled wet gas and dries the wet gas to obtain the regenerated dry gas, which circulates into the molecular sieve regeneration system. The absorption heat pump device is used to receive a fourth heat-conducting substance and heat the fourth heat-conducting substance by absorbing the heat in the heat exchange process of the wet gas to obtain a third heat-conducting substance. The molecular sieve regeneration system is also used to receive the third heat-conducting substance and heat the received dry gas through the third heat-conducting substance. By recycling the waste heat at the top of the molecular sieve regeneration system through the absorption heat pump system to heat the heating medium (the third heat-conducting substance) of the molecular sieve regeneration system, the steam or heat-conducting oil used for heating the molecular sieve regeneration system is saved, the waste heat utilization is realized, and the purpose of saving energy consumption is achieved.

[0042] Other features and advantages of the present invention will be described in the following specification, and, in part, will be obvious from the specification, or will be understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained by the structures specifically pointed out in the written specification, claims, and drawings.

[0043] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Description of the Drawings

[0044] The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention, and do not constitute a limitation to the present invention. In the accompanying drawings:

[0045] Figure 1 It is one of the structural schematic diagrams of the gas dehydration system in Embodiment 1 of the present invention;

[0046] Figure 2 It is the second of the structural schematic diagrams of the gas dehydration system in Embodiment 2 of the present invention;

[0047] Figure 3 It is one of the flowcharts of the gas dehydration method in the embodiments of the present invention;

[0048] Figure 4 It is the second of the flowcharts of the gas dehydration method in the embodiments of the present invention;

[0049] Reference Signs:

[0050] 1 - Triethylene Glycol Regeneration System; 2 - Absorption Heat Pump Device; 3 - Rich and Lean Liquid Heat Exchanger; 4 - Molecular Sieve Regeneration System; 5 - Gas - Liquid Separation System;

[0051] 101 - Triethylene Glycol Fractionating Tower; 102 - Reboiler; 103 - Buffer Tank; 104 - Lean Liquid Pump; 201 - Evaporator; 202 - Absorber; 203 - Generator; 401 - Molecular Sieve Regeneration Tower; 402 - Heater; 501 - Cooler; 502 - Gas - Liquid Separation Tank. Detailed Embodiments

[0052] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be completely conveyed to those skilled in the art.

[0053] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation on the invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0054] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0055] Embodiment 1

[0056] In order to solve the problem of high energy consumption in the gas dehydration process in the prior art, an embodiment of the present invention provides a gas dehydration system, which is particularly suitable for the deep dehydration process of CO2 and the natural gas dehydration process in oil and gas field surface engineering. Its structure is as shown in Figure 1 and includes: a dehydration device (not shown in the figure), a triethylene glycol regeneration system, and an absorption heat pump device;

[0057] The dehydration device, the triethylene glycol regeneration system, and the absorption heat pump device are connected to form a triethylene glycol circulation loop;

[0058] The triethylene glycol dehydration and regeneration system is connected to the absorption heat pump device to form a first circulation loop of the heat-conducting substance;

[0059] The triethylene glycol dehydration and regeneration system is used to receive the rich triethylene glycol solution and heat the received rich triethylene glycol solution to obtain the regenerated lean triethylene glycol solution; the absorption heat pump device is used to receive the regenerated lean triethylene glycol solution and cool the received regenerated lean triethylene glycol solution; the dehydration device is used to receive the cooled regenerated lean triethylene glycol solution and generate the rich triethylene glycol solution;

[0060] The triethylene glycol dehydration and regeneration system is also used to receive the first heat-conducting substance and heat the received rich triethylene glycol solution with the first heat-conducting substance to obtain the second heat-conducting substance; the absorption heat pump device is also used to receive the second heat-conducting substance and heat the received second heat-conducting substance to obtain the first heat-conducting substance, and the temperature of the first heat-conducting substance is higher than that of the second heat-conducting substance.

[0061] In this system, an absorption heat pump device is provided to complete a triethylene glycol circulation loop and a first heat-conducting medium circulation loop in the system. In the triethylene glycol circulation loop and the first heat-conducting medium circulation loop, the absorption heat pump device uses the medium and low-grade heat source after the regeneration of triethylene glycol as the driving force, utilizes the heat potential difference between the medium-temperature heat source and the low-temperature heat source to produce heat higher than the medium-temperature heat source, transfers part of the medium and low heat energy to a higher temperature level, improves the utilization grade of heat energy, and saves the heating energy consumption in the triethylene glycol dehydration and regeneration process.

[0062] Optionally, there are various choices for the absorption heat pump device. For example, a lithium bromide-water absorption heat pump or an ammonia-water absorption heat pump, etc. The embodiments of the present invention do not limit this.

[0063] In some optional embodiments, the triethylene glycol regeneration system includes a triethylene glycol regeneration device and a lean liquid pump;

[0064] Among them, the triethylene glycol regeneration device is respectively connected to one end of the lean liquid pump and the dehydration device; the triethylene glycol regeneration device is used to receive the triethylene glycol rich liquid and heat-treat the received triethylene glycol rich liquid to obtain the regenerated triethylene glycol lean liquid;

[0065] The other end of the lean liquid pump is connected to the absorption heat pump device; the lean liquid pump is used to transport the regenerated triethylene glycol lean liquid into the absorption heat pump device.

[0066] Optionally, the triethylene glycol regeneration device includes a triethylene glycol fractionating column, a reboiler, a buffer tank and a lean liquid pump;

[0067] The bottom of the triethylene glycol fractionating column, the reboiler, the buffer tank and one end of the lean liquid pump are connected in sequence; the top of the triethylene glycol fractionating column is connected to the rich and lean liquid heat exchanger; the other end of the lean liquid pump is connected to the absorption heat pump device;

[0068] The triethylene glycol fractionating column is used to receive the triethylene glycol rich liquid that needs to be regenerated, the reboiler is used to receive the first heat-conducting medium, and under the action of the first heat-conducting medium, the water in the triethylene glycol rich liquid is evaporated to obtain the regenerated triethylene glycol lean liquid (that is, the regenerated triethylene glycol solution), the buffer tank is used to receive the regenerated triethylene glycol lean liquid overflowing from the triethylene glycol fractionating column, and the lean liquid pump is used to receive the regenerated triethylene glycol lean liquid discharged from the buffer tank and send the regenerated triethylene glycol lean liquid into the absorption heat pump device.

[0069] The system described in the embodiments of the present invention may further include: a rich and lean liquid heat exchanger;

[0070] The rich and lean liquid heat exchanger is respectively connected to the triethylene glycol fractionating column, the absorption heat pump device and the dehydration device. The rich and lean liquid heat exchanger is used to receive the triethylene glycol rich liquid or the regenerated triethylene glycol lean liquid and perform heat exchange treatment on the triethylene glycol rich liquid or the regenerated triethylene glycol lean liquid so that the temperature of the triethylene glycol rich liquid rises and the temperature of the regenerated triethylene glycol lean liquid drops.

[0071] In some alternative embodiments, the absorption heat pump device includes an evaporator, a generator, and an absorber;

[0072] The evaporator is configured to receive a stream of regenerated lean triethylene glycol solution and cool the received regenerated lean triethylene glycol solution.

[0073] The generator is configured to receive another stream of regenerated lean triethylene glycol solution and cool the received regenerated lean triethylene glycol solution.

[0074] The absorber is connected to the triethylene glycol regeneration device; the absorber is configured to receive a second heat-conducting substance and also release heat to heat the received second heat-conducting substance to obtain a first heat-conducting substance; the triethylene glycol regeneration device is further configured to receive the first heat-conducting substance and use the received first heat-conducting substance to heat the triethylene glycol rich solution to obtain the second heat-conducting substance.

[0075] It should be noted that the lean solution pump sends the regenerated lean triethylene glycol solution to the absorption heat pump device in two paths. Specifically, the lean solution pump divides the received triethylene glycol lean solution and sends it to the evaporator and the generator of the absorption heat pump device in two paths respectively; the evaporator and the generator respectively perform heat exchange and cooling on the received regenerated lean triethylene glycol solution. Correspondingly, the evaporator and the generator absorb part of the residual temperature (medium and low-grade heat energy) of the regenerated lean triethylene glycol solution. Driven by the part of the residual temperature of the absorbed regenerated lean triethylene glycol solution, water vapor is generated, and the water vapor and part of the heat are transferred to the absorber. The absorber receives the water vapor from the evaporator, dilutes the concentrated solution inside, and releases higher heat, realizing the process of transferring the medium and low-grade heat energy in the absorber to a higher temperature level to produce heat higher than the medium-temperature heat source. The heat of the produced medium-temperature heat source is used to heat the received second heat-conducting substance to obtain the first heat-conducting substance. The first heat-conducting substance circulates into the reboiler. The temperature of the first heat-conducting substance is higher than that of the second heat-conducting substance. In fact, the first heat-conducting substance and the second heat-conducting substance are the same substance in two temperature states and can be collectively referred to as the heat-conducting substance. For example, the heat-conducting substance can be selected as steam. Correspondingly, the first heat-conducting substance is high-temperature steam and the second heat-conducting substance is low-temperature steam.

[0076] To more clearly illustrate the gas dehydration system, the following combines Figure 1 , and details the working process of the gas dehydration system:

[0077] The rich triethylene glycol solution enters the rich-lean liquid heat exchanger and exchanges heat therein, causing the temperature of the rich triethylene glycol solution to increase initially. The rich triethylene glycol solution with the initially increased temperature enters the triethylene glycol fractionating column. The reboiler receives high-temperature steam and uses the high-temperature steam to evaporate the water in the rich triethylene glycol solution, obtaining the regenerated lean triethylene glycol solution and water vapor. The water vapor overflows from the top of the triethylene glycol fractionating column. The regenerated lean triethylene glycol solution overflows into the buffer tank and then enters the lean liquid pump from the buffer tank. The lean liquid pump pressurizes the regenerated lean triethylene glycol solution and sends the pressurized lean triethylene glycol solution to the evaporator and the generator respectively. The evaporator and the generator perform heat exchange and cooling treatment on the received lean triethylene glycol solution. After heat exchange in the rich-lean liquid heat exchanger, the cooled lean triethylene glycol solution circulates into the dehydration device to absorb the water in the gas to be dehydrated, generating a rich triethylene glycol solution.

[0078] Example 2

[0079] To solve the problem of high energy consumption in the existing gas process, an embodiment of the present invention provides a gas dehydration system, the structure of which is referred to Figure 2 as shown in the figure, including: a molecular sieve absorption device, a molecular sieve regeneration system, a gas-liquid separation system, and an absorption heat pump device;

[0080] The molecular sieve absorption device, the molecular sieve regeneration system, the absorption heat pump device, and the gas-liquid separation system are connected to form a dry gas circulation loop;

[0081] The molecular sieve regeneration system is connected to the absorption heat pump device to form a second closed loop of the heat-conducting substance;

[0082] The molecular sieve regeneration system is used to receive dry gas and heat the received dry gas, and regenerate the molecular sieve by the heated dry gas to generate wet gas; the absorption heat pump device is used to receive the wet gas and cool the received wet gas; the gas-liquid separation system is used to receive the cooled wet gas and perform cooling and gas-liquid separation treatment on the cooled wet gas; the molecular sieve absorption device is used to receive the wet gas after gas-liquid separation and perform drying treatment on the received wet gas to obtain regenerated dry gas, and the regenerated dry gas circulates into the molecular sieve regeneration system;

[0083] The molecular sieve regeneration system is further used to receive a third heat-conducting substance and heat the received dry gas by the received heat-conducting substance to obtain a fourth heat-conducting substance; the absorption heat pump device is used to receive the fourth heat-conducting substance and heat the received fourth heat-conducting substance to obtain a third heat-conducting substance, and the temperature of the third heat-conducting substance is higher than that of the fourth heat-conducting substance.

[0084] In this system, an absorption heat pump device is provided to complete a dry gas circulation loop and a second closed loop of a heat transfer medium in the system. The waste heat of the high-temperature regenerated gas at the top of the molecular sieve regeneration tower of the absorption heat pump device is recovered and heated by the absorption heat pump device and then used for heating the heating medium of the molecular sieve regeneration tower, saving the steam or heat transfer oil used for heating the molecular sieve regeneration tower and realizing waste heat utilization.

[0085] Optionally, there are various choices for the absorption heat pump device. For example, a lithium bromide-water absorption heat pump or an ammonia-water absorption heat pump, etc. The embodiments of the present invention do not limit this.

[0086] In some alternative embodiments, the molecular sieve regeneration system includes a heater and a molecular sieve regeneration device;

[0087] One end of the heater is connected to the molecular sieve absorption device, and the heater is used to receive dry gas and heat the received dry gas;

[0088] The molecular sieve regeneration device is respectively connected to the other end of the heater and the absorption heat pump device. The molecular sieve regeneration device is used to receive the heated dry gas and perform regeneration treatment on the molecular sieve to generate wet gas.

[0089] In some alternative embodiments, the gas-liquid separation system includes a cooler and a gas-liquid separation tank.

[0090] In some alternative embodiments, the absorption heat pump device includes an evaporator, a generator, and an absorber;

[0091] The evaporator is used to receive a path of wet gas and cool the received wet gas.

[0092] The generator is used to receive another path of wet gas and cool the received wet gas.

[0093] The absorber is connected to the heater. The absorber is used to receive the fourth heat transfer medium and also used to release heat to heat the received fourth heat transfer medium to obtain the third heat transfer medium; the heater is also used to receive the third heat transfer medium and use the third heat transfer medium to heat the received dry gas to obtain the fourth heat transfer medium.

[0094] It should be noted that the high-temperature regenerated gas at the top of the molecular sieve regeneration tower is sent to the absorption heat pump device in two paths respectively.

[0095] For a clearer description of the gas dehydration system, the following combines Figure 2 , and details the working process of the gas dehydration system:

[0096] The dry gas enters the heater for heating to obtain high-temperature dry gas. The high-temperature dry gas enters the molecular sieve regeneration tower to regenerate the molecular sieve and obtain high-temperature wet gas (high-temperature regeneration gas). The regeneration gas enters the evaporator and generator of the absorption heat pump device for heat exchange and cooling. After being cooled by the cooler, the cooled regeneration gas enters the gas-liquid separation tank for separation. The regeneration gas after dehydration and separation is pressurized and then dried. The obtained dry gas enters the molecular sieve regeneration tower for circulation. The high-temperature heat-conducting oil / steam heats the dry gas regenerated in the molecular sieve regeneration tower through the heater. The heat-conducting oil / steam after cooling enters the absorber of the absorption heat pump device for heat exchange and heating, and then returns to the heat-conducting oil furnace / steam boiler for further heating and circulation.

[0097] Based on the same inventive concept, an embodiment of the present invention further provides a gas dehydration method, which is realized by the aforementioned gas dehydration system, and its process reference Figure 3 is shown as follows:

[0098] Step S31: The triethylene glycol dehydration and regeneration system is used to receive the rich triethylene glycol solution and heat the received rich triethylene glycol solution to obtain the regenerated lean triethylene glycol solution; the absorption heat pump device is used to receive the regenerated lean triethylene glycol solution and cool the received regenerated lean triethylene glycol solution; the dehydration device is used to receive the cooled regenerated lean triethylene glycol solution and generate the rich triethylene glycol solution;

[0099] Step S32: The triethylene glycol dehydration and regeneration system is further used to receive the first heat-conducting substance and heat the received rich triethylene glycol solution with the first heat-conducting substance to obtain the second heat-conducting substance; the absorption heat pump device is further used to receive the second heat-conducting substance and heat the received second heat-conducting substance to obtain the first heat-conducting substance, and the temperature of the first heat-conducting substance is higher than that of the second heat-conducting substance.

[0100] Based on the same inventive concept, an embodiment of the present invention further provides a gas dehydration method, which is realized by the aforementioned gas dehydration system, and its process reference Figure 4 is shown as follows:

[0101] Step S41: The molecular sieve regeneration system is used to receive the dry gas and heat the received dry gas. The molecular sieve is regenerated by the heated dry gas to generate wet gas; the absorption heat pump device is used to receive the wet gas and cool the received wet gas; the gas-liquid separation system is used to receive the cooled wet gas and perform cooling and gas-liquid separation processing on the cooled wet gas; the molecular sieve absorption device is used to receive the wet gas after gas-liquid separation and dry the received wet gas to obtain the regenerated dry gas, and the regenerated dry gas circulates into the molecular sieve regeneration system;

[0102] Step S42: The molecular sieve regeneration system is further configured to receive a third heat-conducting substance, and heat the received dry gas with the received heat-conducting substance to obtain a fourth heat-conducting substance; the absorption heat pump device is configured to receive the fourth heat-conducting substance and heat the received fourth heat-conducting substance to obtain a third heat-conducting substance, and the temperature of the third heat-conducting substance is higher than that of the fourth heat-conducting substance.

[0103] Unless otherwise specifically stated, terms such as process, compute, calculate, determine, display, etc. may refer to the actions and / or processes of one or more processing or computing systems, or similar devices, which operate on and transform data represented as physical (such as electronic) quantities within the registers or memories of the processing system into other data similarly represented as physical quantities within the memories, registers, or other such information storage, transmission, or display devices of the processing system. Information and signals can be represented using any of a variety of different technologies and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chipsets mentioned throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0104] It should be understood that the specific order or hierarchy of steps in the disclosed processes are examples of exemplary methods. Based on design preferences, it should be understood that the specific order or hierarchy of steps in a process may be rearranged without departing from the scope of the present disclosure. The appended method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy recited.

[0105] In the above detailed description, various features are combined in a single embodiment to simplify the present disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are expressly recited in each claim. Rather, as reflected in the appended claims, the invention lies in less than all of the features of a single disclosed embodiment. Accordingly, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0106] The foregoing description includes examples of one or more embodiments. Of course, it is not possible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but those of ordinary skill in the art should recognize that the various embodiments can be further combined and arranged. Accordingly, the embodiments described herein are intended to cover all such changes, modifications, and variations that fall within the scope of the appended claims. In addition, with respect to the term "comprising" as used in the specification or claims, that term is inclusive in a manner similar to the term "including" as that term is interpreted when used as a transitional word in a claim. Further, any use of the term "or" in a claim or the specification is to be meant "non-exclusive or".

Claims

1. A gas dehydration system, comprising a dehydration device and a triethylene glycol regeneration system, characterized in that, Further comprising: An absorption heat pump device; The dehydration device, the triethylene glycol regeneration system and the absorption heat pump device are connected to form a triethylene glycol circulation loop; The triethylene glycol dehydration and regeneration system is connected to the absorption heat pump device to form a first circulation loop of the heat-conducting substance; The triethylene glycol dehydration and regeneration system is configured to receive the rich triethylene glycol solution, and heat the received rich triethylene glycol solution to obtain the regenerated lean triethylene glycol solution; the absorption heat pump device is configured to receive the regenerated lean triethylene glycol solution, and cool the received regenerated lean triethylene glycol solution; the dehydration device is configured to receive the cooled regenerated lean triethylene glycol solution and generate the rich triethylene glycol solution; The triethylene glycol dehydration and regeneration system is further configured to receive a first heat-conducting substance, and heat the received rich triethylene glycol solution with the first heat-conducting substance to obtain a second heat-conducting substance; The absorption heat pump device is further configured to receive the second heat-conducting substance, and heat the received second heat-conducting substance to obtain the first heat-conducting substance, and the temperature of the first heat-conducting substance is higher than that of the second heat-conducting substance.

2. The gas dehydration system according to claim 1, wherein The triethylene glycol regeneration system includes a triethylene glycol regeneration device and a lean solution pump; The triethylene glycol regeneration device is respectively connected to one end of the lean solution pump and the dehydration device; the triethylene glycol regeneration device is configured to receive the rich triethylene glycol solution, and heat the received rich triethylene glycol solution to obtain the regenerated lean triethylene glycol solution; The other end of the lean solution pump is connected to the absorption heat pump device; the lean solution pump is configured to transport the regenerated lean triethylene glycol solution to the absorption heat pump device.

3. The gas dehydration system according to claim 2, characterized in that, The absorption heat pump device includes an evaporator; The evaporator is configured to receive a path of the regenerated lean triethylene glycol solution, and cool the received regenerated lean triethylene glycol solution.

4. The gas dehydration system according to claim 2, wherein The absorption heat pump device includes a generator; The generator is configured to receive another path of the regenerated lean triethylene glycol solution, and cool the received regenerated lean triethylene glycol solution.

5. The gas dehydration system according to claim 3, wherein The absorption heat pump device further includes an absorber; The absorber is connected to the triethylene glycol regeneration device; the absorber is configured to receive the second heat-conducting substance, and is further configured to release heat to heat the received second heat-conducting substance to obtain the first heat-conducting substance; the triethylene glycol regeneration device is further configured to receive the first heat-conducting substance, and heat the rich triethylene glycol solution with the received first heat-conducting substance to obtain the second heat-conducting substance.

6. A gas dehydration system, comprising a molecular sieve absorption device, a molecular sieve regeneration system, and a gas-liquid separation system, characterized in that, Further comprising: An absorption heat pump device; The molecular sieve absorption device, the molecular sieve regeneration system, the absorption heat pump device, and the gas-liquid separation system are connected to form a dry gas circulation loop; The molecular sieve regeneration system is connected to the absorption heat pump device to form a second closed loop of the heat-conducting substance; The molecular sieve regeneration system is configured to receive dry gas, heat the received dry gas, and regenerate the molecular sieve with the heated dry gas to generate wet gas; the absorption heat pump device is configured to receive the wet gas and cool the received wet gas; the gas-liquid separation system is configured to receive the cooled wet gas, and perform cooling and gas-liquid separation processing on the cooled wet gas; The molecular sieve absorption device is used to receive the wet gas after gas-liquid separation and dry the received wet gas to obtain regenerated dry gas, and the regenerated dry gas circulates into the molecular sieve regeneration system; The molecular sieve regeneration system is also used to receive the third heat-conducting substance and heat the received dry gas with the received heat-conducting substance to obtain the fourth heat-conducting substance; The absorption heat pump device is used to receive the fourth heat-conducting substance and heat the received fourth heat-conducting substance to obtain the third heat-conducting substance, and the temperature of the third heat-conducting substance is higher than that of the fourth heat-conducting substance.

7. The gas dehydration system according to claim 6, wherein The molecular sieve regeneration system includes a heater and a molecular sieve regeneration device; One end of the heater is connected to the molecular sieve absorption device, and the heater is used to receive dry gas and heat the received dry gas; The molecular sieve regeneration device is respectively connected to the other end of the heater and the absorption heat pump device, and the molecular sieve regeneration device is used to receive the heated dry gas and regenerate the molecular sieve to generate wet gas.

8. The gas dehydration system according to claim 7, wherein, The absorption heat pump device includes an evaporator; The evaporator is used to receive a stream of wet gas and cool the received wet gas.

9. The gas dehydration system according to claim 7, wherein, The absorption heat pump device includes a generator; The generator is used to receive another stream of wet gas and cool the received wet gas.

10. The gas dehydration system according to claim 8, characterized in that, The absorption heat pump device further includes an absorber; The absorber is connected to the heater. The absorber is used to receive the fourth heat-conducting substance and also used to release heat to heat the received fourth heat-conducting substance to obtain the third heat-conducting substance; the heater is also used to receive the third heat-conducting substance and heat the received dry gas with the third heat-conducting substance to obtain the fourth heat-conducting substance.

11. A gas dehydration method, which is realized by the gas dehydration system described in claims 1-5, characterized in that, Including: The triethylene glycol dehydration and regeneration system is used to receive the rich triethylene glycol solution and heat the received rich triethylene glycol solution to obtain the regenerated lean triethylene glycol solution; the absorption heat pump device is used to receive the regenerated lean triethylene glycol solution and cool the received regenerated lean triethylene glycol solution; the dehydration device is used to receive the cooled regenerated lean triethylene glycol solution and generate the rich triethylene glycol solution; The triethylene glycol dehydration and regeneration system is also used to receive the first heat-conducting substance and heat the received rich triethylene glycol solution with the first heat-conducting substance to obtain the second heat-conducting substance; The absorption heat pump device is also used to receive the second heat-conducting substance and heat the received second heat-conducting substance to obtain the first heat-conducting substance, and the temperature of the first heat-conducting substance is higher than that of the second heat-conducting substance.

12. A gas dehydration method, which is realized by the gas dehydration system described in claims 6-10, characterized in that, Including: The molecular sieve regeneration system is used to receive dry gas, heat the received dry gas, and regenerate the molecular sieve with the heated dry gas to generate wet gas; The absorption heat pump device is used to receive wet gas and cool the received wet gas; the gas-liquid separation system is used to receive the cooled wet gas and perform cooling and gas-liquid separation treatment on the cooled wet gas; The molecular sieve absorption device is used to receive the wet gas after gas-liquid separation and dry the received wet gas to obtain regenerated dry gas, and the regenerated dry gas circulates into the molecular sieve regeneration system; The molecular sieve regeneration system is also used to receive the third heat-conducting substance and heat the received dry gas with the received heat-conducting substance to obtain the fourth heat-conducting substance; An absorption heat pump device is used to receive a fourth heat-conducting substance and heat the received fourth heat-conducting substance to obtain a third heat-conducting substance, and the temperature of the third heat-conducting substance is higher than that of the fourth heat-conducting substance.

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