Molecular sieve dehydration device and method utilizing photo-thermal energy supply

Abstract

The invention discloses a molecular sieve dehydration device and method utilizing photo-thermal energy supply, and relates to the technical field of natural gas purification. The dehydration device comprises a dehydration tower I, a dehydration tower II, a dust filter, a regenerated gas heater, a regenerated gas cooler, a regenerated gas separator, a photo-thermal heating system, a heat conduction oil circulating tank, a heat conduction oil circulating pump and a photo-thermal control system; the invention further provides a dehydration method. Compared with the traditional two-tower dehydration process, the heat-conducting oil is heated by fully utilizing photo-thermal energy to supply heat, and the regeneration system realizes the regeneration functions of heating in the presence of light and cold blowing in the absence of light. The biggest photo-thermal advantage is that the consumption of fossil energy is greatly reduced, and the device is clean and pollution-free; and meanwhile, the photo-thermal heating system absorbs sunlight to heat the heat-conducting oil, and the heating speed and efficiency are higher than those of natural gas heating.

Description

Technical Field

[0001] The present invention relates to the technical field of natural gas purification, and in particular to a molecular sieve dehydration device and method utilizing photothermal energy supply. Background Art

[0002] The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

[0003] Gas dehydration methods generally include membrane separation, solid adsorption, solvent absorption, cryogenic methods, etc. Solid adsorption dehydration usually uses desiccants such as molecular sieves and activated alumina for adsorption dehydration, and the molecular sieves after adsorption are then heated with regenerated gas to remove moisture.

[0004] The commonly used dehydration process is the two-tower dehydration process. In the current two-tower dehydration device, the regeneration gas of the desiccant is usually a low-pressure gas that is first heated and then desorbed in the dehydration tower after adsorption of water, and then the gas heater stops working, and the regeneration gas from the same source is cold-blown in the dehydration tower after heating and desorption, and then cooled and separated to enter the downstream process. Since the regeneration gas is usually heated with fuel gas or electricity as the heat source, the energy consumption required by the heating system is relatively high. Summary of the invention

[0005] The purpose of the present invention is to provide a molecular sieve dehydration device and method using photothermal energy to address the problems existing in the prior art, thereby achieving heating of the regenerated gas by photothermal energy, and also independently setting up a set of photothermal heating system to heat the regenerated gas for regeneration of the dehydration tower.

[0006] The technical solution of the present invention is as follows:

[0007] A molecular sieve dehydration device using photothermal energy, comprising: a dehydration tower I, a dehydration tower II, a dust filter, a regeneration gas heater, a regeneration gas cooler and a regeneration gas separator;

[0008] The tops of the dehydration towers I and II are respectively connected to the wet raw gas pipeline; the tops of the dehydration towers I and II are also respectively connected to the regeneration pipeline II, the regeneration gas cooler is arranged on the regeneration pipeline II, and the end of the regeneration pipeline II is connected to the regeneration gas separator;

[0009] The bottoms of the dehydration towers I and II are respectively connected to the inlet of the dust filter; the bottoms of the dehydration towers I and II are also respectively connected to the regeneration pipeline I, the end of the regeneration pipeline I is connected to the outlet of the regeneration gas heater, and the inlet of the regeneration gas heater is connected to the outlet of the dust filter; the outlet of the dust filter is also connected to the regeneration pipeline I; the regeneration pipeline I is also connected to the regeneration pipeline II.

[0010] Furthermore, it also includes: a solar thermal heating system, a thermal oil circulation tank and a thermal oil circulation pump;

[0011] The thermal oil output end of the photothermal heating system is connected to the thermal oil input end of the regeneration gas heater, the thermal oil output end of the regeneration gas heater is connected to the thermal oil input end of the thermal oil circulation tank, and the thermal oil output end of the thermal oil circulation tank is connected to the photothermal heating system.

[0012] Further, it also includes: a light and heat control system;

[0013] The photothermal control system is used to monitor the temperature of the heated regenerated gas and control the photothermal heating system to heat the heat transfer oil.

[0014] Furthermore, a KV-1A valve is provided on the pipeline connecting the top of the dehydration tower I and the wet raw gas pipeline, and a KV-3A valve is provided on the pipeline connecting the top of the dehydration tower I and the regeneration pipeline II;

[0015] A KV-1B valve is provided on the pipeline connecting the top of the dehydration tower II and the wet raw gas pipeline, and a KV-3B valve is provided on the pipeline connecting the top of the dehydration tower II and the regeneration pipeline II.

[0016] Furthermore, a KV-2A valve is provided on the pipeline connecting the bottom of the dehydration tower I and the dust filter inlet, and a KV-4A valve is provided on the pipeline connecting the bottom of the dehydration tower I and the regeneration pipeline I;

[0017] A KV-2B valve is provided on the pipeline connecting the bottom of the dehydration tower II and the dust filter inlet, and a KV-4B valve is provided on the pipeline connecting the bottom of the dehydration tower II and the regeneration pipeline I.

[0018] Furthermore, a KV-5 valve is provided on the pipeline connecting the regeneration pipeline I and the regeneration pipeline II, a KV-6 valve is provided on the pipeline connecting the dust filter outlet and the regeneration pipeline I, and a KV-7 valve is provided on the pipeline connecting the dust filter outlet and the regeneration gas heater inlet.

[0019] A molecular sieve dehydration method using photothermal energy supply, based on the above molecular sieve dehydration device, comprising:

[0020] Molecular sieve dehydration is achieved by controlling KV-1A valve, KV-1B valve, KV-2A valve, KV-2B valve, KV-3A valve, KV-3B valve, KV-4A valve, KV-4B valve, KV-5 valve, KV-6 valve and KV-7 valve.

[0021] Furthermore, when only dehydration tower I is performing the adsorption dehydration process, it is only necessary to control the KV-1A valve and the KV-2A valve to be opened, and the other valves to be closed;

[0022] When only dehydration tower II is performing the adsorption dehydration process, it is only necessary to control the KV-1B valve and KV-2B valve to be opened, and the other valves to be closed.

[0023] Furthermore, when dehydration tower I is in adsorption and dehydration tower II is in regeneration heating, it is only necessary to control KV-1A valve, KV-2A valve, KV-7 valve, KV-4B valve, and KV-3B valve to be opened, and the remaining valves to be closed.

[0024] Furthermore, when the dehydration tower I is adsorbed and the dehydration tower II is regenerated and heated for cold blowing, it is only necessary to control the KV-1A valve, KV-2A valve, KV-6 valve, KV-4B valve, and KV-3B valve to be opened, and the other valves to be closed.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] A molecular sieve dehydration device and method using photothermal energy supply. Compared with the traditional two-tower dehydration process, the present invention fully utilizes the energy of photothermal to heat the thermal oil for heating, and the regeneration system realizes the regeneration function of heating when there is light and cooling when there is no light. The biggest advantage of photothermal is that it greatly reduces the consumption of fossil energy and is clean and pollution-free; at the same time, the photothermal heating system absorbs sunlight to heat the thermal oil, which is faster and more efficient than natural gas heating. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the structure of a molecular sieve dehydration device using photothermal energy;

[0028] Figure 2 Schematic diagram of adsorption in dehydration tower I;

[0029] Figure 3 This is a schematic diagram of the heating regeneration of the dehydration tower II;

[0030] Figure 4 This is a schematic diagram of the cold-blowing regeneration of dehydration tower II.

[0031] Figure numerals: 1-dehydration tower I, 2-dehydration tower II, 3-regeneration gas cooler, 4-regeneration gas separator, 5-photothermal control system, 6-photothermal heating system, 7-thermal oil circulation tank, 8-thermal oil circulation pump, 9-regeneration gas heater, 10-dust filter. DETAILED DESCRIPTION

[0032] It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0033] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0034] Embodiment 1

[0035] See also Figure 1 , a molecular sieve dehydration device using photothermal energy, comprising: a dehydration tower Ⅰ1, a dehydration tower Ⅱ2, a dust filter 10, a regeneration gas heater 9, a regeneration gas cooler 3 and a regeneration gas separator 4;

[0036] The tops of the dehydration towers Ⅰ1 and Ⅱ2 are connected to the wet raw gas pipeline respectively; the tops of the dehydration towers Ⅰ1 and Ⅱ2 are also connected to the regeneration pipeline Ⅱ respectively, the regeneration gas cooler 3 is arranged on the regeneration pipeline Ⅱ, and the end of the regeneration pipeline Ⅱ is connected to the regeneration gas separator 4; that is, the dehydration towers Ⅰ1 and Ⅱ2 are arranged between the wet raw gas pipeline (i.e., the raw gas inlet pipeline) and the dry raw gas pipeline (i.e., the dryer outflow pipeline); it should be noted that the gas phase of the regeneration gas separator 4 can enter the downstream process, which will not be described in detail here;

[0037] The bottoms of the dehydration towers Ⅰ1 and Ⅱ2 are respectively connected to the inlets of the dust filter 10; the bottoms of the dehydration towers Ⅰ1 and Ⅱ2 are also respectively connected to the regeneration pipeline Ⅰ, the end of the regeneration pipeline Ⅰ is connected to the outlet of the regeneration gas heater 9, and the inlet of the regeneration gas heater 9 is connected to the outlet of the dust filter 10; the outlet of the dust filter 10 is also connected to the regeneration pipeline Ⅰ; the regeneration pipeline Ⅰ is also connected to the regeneration pipeline Ⅱ.

[0038] In this embodiment, specifically, it also includes: a photothermal heating system 6, a thermal oil circulation tank 7 and a thermal oil circulation pump 8;

[0039] The thermal oil output end of the photothermal heating system 6 is connected to the thermal oil input end of the regeneration gas heater 9, the thermal oil output end of the regeneration gas heater 9 is connected to the thermal oil input end of the thermal oil circulation tank 7, and the thermal oil output end of the thermal oil circulation tank 7 is connected to the photothermal heating system 6.

[0040] In this embodiment, specifically, it also includes: a light and heat control system 5;

[0041] The photothermal control system 5 is used to monitor the temperature of the heated regenerated gas and control the photothermal heating system 6 to heat the thermal oil;

[0042] That is, the thermal oil circulation pump 8 is used to pump the thermal oil in the thermal oil circulation tank 7 into the photothermal heating system 6, and the thermal oil is heated to the required temperature by photothermal heating. The heated thermal oil enters the regeneration gas heater 9 to heat the regeneration dry gas and then returns to the thermal oil circulation tank 7. The temperature of the heated regeneration gas is monitored by the photothermal control system 5 and the photothermal heating system 6 is used to control the temperature stability of the regeneration gas.

[0043] In this embodiment, specifically, a KV-1A valve is provided on the pipeline connecting the top of the dehydration tower Ⅰ1 and the wet raw gas pipeline, and a KV-3A valve is provided on the pipeline connecting the top of the dehydration tower Ⅰ1 and the regeneration pipeline Ⅱ;

[0044] A KV-1B valve is provided on the pipeline connecting the top of the dehydration tower II2 and the wet raw gas pipeline, and a KV-3B valve is provided on the pipeline connecting the top of the dehydration tower II2 and the regeneration pipeline II;

[0045] A KV-2A valve is provided on the pipeline connecting the bottom of the dehydration tower Ⅰ1 and the inlet of the dust filter 10, and a KV-4A valve is provided on the pipeline connecting the bottom of the dehydration tower Ⅰ1 and the regeneration pipeline Ⅰ;

[0046] A KV-2B valve is provided on the pipeline connecting the bottom of the dehydration tower II2 and the inlet of the dust filter 10, and a KV-4B valve is provided on the pipeline connecting the bottom of the dehydration tower II2 and the regeneration pipeline I;

[0047] A KV-5 valve is provided on the pipeline connecting the regeneration pipeline I and the regeneration pipeline II, a KV-6 valve is provided on the pipeline connecting the outlet of the dust filter 10 and the regeneration pipeline I, and a KV-7 valve is provided on the pipeline connecting the outlet of the dust filter 10 and the inlet of the regeneration gas heater 9;

[0048] It should be noted that the above-mentioned KV-1A valve, KV-1B valve, KV-2A valve, and KV-2B valve belong to the adsorption program KV valves, which are controlled by the adsorption program; the above-mentioned KV-3A valve, KV-3B valve, KV-4A valve, KV-4B valve, KV-5 valve, KV-6 valve, and KV-7 valve belong to the regeneration program KV valves, which are controlled by the regeneration program. At the same time, for the adsorption program and the regeneration program, those skilled in the art can complete the writing based on the molecular sieve dehydration method proposed in the present invention, which will not be repeated here.

[0049] The specific usage is as follows:

[0050] Step 1: Raw natural gas enters dehydration tower Ⅰ1 or dehydration tower Ⅱ2 through KV-1A valve or KV-1B valve for adsorption, and then the dry gas enters dust filter 10 through KV-2A valve or KV-2B valve and enters the downstream process.

[0051] Step 2: The dry gas after passing through the dust filter 10 enters the regeneration gas heater 9 through the KV-7 valve, and the heated dry gas enters the dehydration tower through the KV-4A valve or the KV-4B valve to achieve hot-blow regeneration. The regeneration gas that has completed the hot-blow regeneration in the dehydration tower enters the regeneration gas cooler 3 through the KV-3A valve or the KV-3B valve, and the cooled regeneration gas is separated into the liquid phase by the regeneration gas separator 4 and enters the downstream sewage pipeline, and the gas phase enters the downstream process.

[0052] Step 3: Use the thermal oil circulation pump 8 to pump the thermal oil in the thermal oil circulation tank 7 into the photothermal heating system 6, and heat the thermal oil to the required temperature through photothermal heating. The heated thermal oil enters the regeneration gas heater 9 to heat the regeneration dry gas and then returns to the thermal oil circulation tank 7. The control system monitors the temperature of the heated regeneration gas and the photothermal heating system 6 to achieve temperature stability of the regeneration gas.

[0053] Step 4: The dry gas after passing through the dust filter 10 enters the branch line of the regeneration gas heater 9 through the KV-6 valve, and the dry gas enters the dehydration tower through the KV-4A valve or the KV-4B valve to achieve cold blowing regeneration. The regeneration gas that has completed the cold blowing of the dehydration tower enters the regeneration gas cooler 3 through the KV-3A valve or the KV-3B valve. The cooled regeneration gas is separated into the liquid phase by the regeneration gas separator 4 and enters the downstream sewage pipeline, and the gas phase enters the downstream process.

[0054] Embodiment 2

[0055] When only dehydration tower Ⅰ1 is performing adsorption dehydration process, only KV-1A valve and KV-2A valve need to be controlled to open, and other valves need to be closed;

[0056] When only dehydration tower Ⅱ2 is performing adsorption dehydration process, it is only necessary to control KV-1B valve and KV-2B valve to be opened, and the other valves to be closed.

[0057] See also Figure 2 , the thick black line in the figure is the flow path; taking the adsorption dehydration process of dehydration tower Ⅰ1 as an example, it specifically includes:

[0058] The wet raw gas enters the dehydration tower I1 through the KV-1A valve, where it undergoes adsorption dehydration. The dehydrated dry gas enters the dust filter 10 through the KV-2A valve for filtration and then passes to the downstream process.

[0059] Embodiment 3

[0060] When dehydration tower I is adsorbing and dehydration tower II2 is in regeneration heating, it is only necessary to control KV-1A valve, KV-2A valve, KV-7 valve, KV-4B valve, and KV-3B valve to open, and the other valves to close.

[0061] See also Figure 3 , the thick black line in the figure is the flow path; taking the dehydration tower I adsorption and the dehydration tower II2 in regeneration heating as an example, it specifically includes:

[0062] The outlet raw dry gas of the dust filter 10 enters the regeneration gas heater 9 through the KV-7 valve for heating and temperature increase. The heated regeneration gas passes through the regeneration gas heater 9 and the dehydration tower Ⅱ2 connecting pipeline, and enters the dehydration tower Ⅱ2 through the KV-4B valve to regenerate and heat the dehydration tower Ⅱ2. The regeneration gas that completes the regeneration process passes through the KV-3B valve and enters the regeneration gas cooler 3 through the regeneration pipeline Ⅱ for cooling. The cooled regeneration gas enters the regeneration gas separator 4 through the outlet pipeline of the regeneration gas cooler 3 for gas-liquid separation. The gas phase in the regeneration gas separator 4 is passed to the downstream process through the gas phase outlet pipeline of the regeneration gas separator 4.

[0063] Embodiment 4

[0064] When the dehydration tower I adsorbs and the dehydration tower Ⅱ2 regenerates and heats up before cold blowing, it is only necessary to control the KV-1A valve, KV-2A valve, KV-6 valve, KV-4B valve, and KV-3B valve to open, and the other valves to close.

[0065] See also Figure 4 The thick black line in the figure is the flow path; taking the dehydration tower I adsorption, the dehydration tower II 2 regeneration heating after the cold blowing as an example, specifically including:

[0066] The raw dry gas from the outlet of the dust filter 10 passes through a branch pipeline, passes through the KV-6 valve and the KV-4B valve, enters the dehydration tower Ⅱ2, and performs cold blowing on the dehydration tower Ⅱ2. The regenerated gas after cold blowing passes through the KV-3B valve, and enters the regenerated gas separator 4 through the regenerated gas cooler 3 for gas-liquid separation. The gas phase in the regenerated gas separator 4 enters the downstream process through the gas phase outlet pipeline of the regenerated gas separator 4.

[0067] That is, the dehydration towers in the dehydration device of the present invention are switched in sequence according to adsorption, heating / cold blowing. In the first cycle (such as Figure 2 , Figure 3 and Figure 4 ), the dehydration tower I performs the adsorption process, while the dehydration tower II2 first performs the heating process (such as Figure 3 ), and then cold blowing process (such as Figure 4 ).

[0068] Therefore, in the next cycle, the dehydration tower II2 that has completed the cold blowing switches to the adsorption dehydration process, and the dehydration tower I first switches to the regeneration heating process. At this time, the KV-1B valve and the KV-2B valve are switched to the open state, the KV-1A valve and the KV-2A valve are switched to the closed state, the KV-3B valve and the KV-4B valve are switched to the closed state, and the KV-3A valve and the KV-4A valve are switched to the open state.

[0069] After the regeneration heating of dehydration tower I is completed, it switches to the cold blowing process, and dehydration tower II 2 is still performing the adsorption dehydration process.

[0070] The above two cycle times can be exactly the same. After the second cycle is completed, the two dehydration towers are operated again in the first cycle (such as Figure 2 , Figure 3 and Figure 4 ), and then repeat the above process.

[0071] The above-mentioned embodiments only express the specific implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the protection scope of the present application. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the technical solution concept of the present application, and these all belong to the protection scope of the present application.

[0072] This background section is provided to generally present the context of the invention, and the work of the presently named inventors, the work to the extent described in this background section, and aspects of this section that did not constitute prior art at the time of application are neither explicitly nor implicitly admitted to be prior art to the present invention.

Claims

1. A molecular sieve dehydration device using photothermal energy, It is characterized in that include: Dehydration tower I (1), dehydration tower II (2), dust filter (10), regeneration gas heater (9), regeneration gas cooler (3) and regeneration gas separator (4); The tops of the dehydration tower I (1) and the dehydration tower II (2) are respectively connected to the wet raw gas pipeline; the tops of the dehydration tower I (1) and the dehydration tower II (2) are also respectively connected to the regeneration pipeline II, the regeneration gas cooler (3) is arranged on the regeneration pipeline II, and the end of the regeneration pipeline II is connected to the regeneration gas separator (4); The bottoms of the dehydration towers I (1) and II (2) are respectively connected to the inlet of the dust filter (10); the bottoms of the dehydration towers I (1) and II (2) are also respectively connected to the regeneration pipeline I, the end of the regeneration pipeline I is connected to the outlet of the regeneration gas heater (9), the inlet of the regeneration gas heater (9) is connected to the outlet of the dust filter (10); the outlet of the dust filter (10) is also connected to the regeneration pipeline I; the regeneration pipeline I is also connected to the regeneration pipeline II.

2. A molecular sieve dehydration device using photothermal energy according to claim 1, It is characterized in that Also includes: A solar thermal heating system (6), a thermal oil circulation tank (7) and a thermal oil circulation pump (8); The thermal oil output end of the photothermal heating system (6) is connected to the thermal oil input end of the regeneration gas heater (9), the thermal oil output end of the regeneration gas heater (9) is connected to the thermal oil input end of the thermal oil circulation tank (7), and the thermal oil output end of the thermal oil circulation tank (7) is connected to the photothermal heating system (6).

3. A molecular sieve dehydration device using photothermal energy according to claim 2, It is characterized in that Also includes: Photothermal control system (5); The photothermal control system (5) is used to monitor the temperature of the heated regenerated gas and control the photothermal heating system (6) to heat the heat transfer oil.

4. A molecular sieve dehydration device using photothermal energy according to claim 1, It is characterized in that A KV-1A valve is provided on the pipeline connecting the top of the dehydration tower I (1) with the wet raw gas pipeline, and a KV-3A valve is provided on the pipeline connecting the top of the dehydration tower I (1) with the regeneration pipeline II; A KV-1B valve is provided on the pipeline connecting the top of the dehydration tower II (2) with the wet raw gas pipeline, and a KV-3B valve is provided on the pipeline connecting the top of the dehydration tower II (2) with the regeneration pipeline II.

5. A molecular sieve dehydration device using photothermal energy according to claim 4, It is characterized in that A KV-2A valve is provided on the pipeline connecting the bottom of the dehydration tower I (1) and the inlet of the dust filter (10), and a KV-4A valve is provided on the pipeline connecting the bottom of the dehydration tower I (1) and the regeneration pipeline I; A KV-2B valve is provided on the pipeline connecting the bottom of the dehydration tower II (2) and the inlet of the dust filter (10), and a KV-4B valve is provided on the pipeline connecting the bottom of the dehydration tower II (2) and the regeneration pipeline I.

6. A molecular sieve dehydration device using photothermal energy according to claim 5, It is characterized in that A KV-5 valve is provided on the pipeline connecting the regeneration pipeline I and the regeneration pipeline II, a KV-6 valve is provided on the pipeline connecting the outlet of the dust filter (10) and the regeneration pipeline I, and a KV-7 valve is provided on the pipeline connecting the outlet of the dust filter (10) and the inlet of the regeneration gas heater (9).

7. A molecular sieve dehydration method using photothermal energy, It is characterized in that The molecular sieve dehydration device according to any one of claims 1 to 6 comprises: Molecular sieve dehydration is achieved by controlling KV-1A valve, KV-1B valve, KV-2A valve, KV-2B valve, KV-3A valve, KV-3B valve, KV-4A valve, KV-4B valve, KV-5 valve, KV-6 valve and KV-7 valve.

8. A method for dehydrating molecular sieves using photothermal energy according to claim 7, It is characterized in that When only dehydration tower Ⅰ(1) is performing the adsorption dehydration process, only valves KV-1A and KV-2A need to be opened, and the other valves closed; When only dehydration tower II (2) is performing the adsorption dehydration process, it is only necessary to control valves KV-1B and KV-2B to be open, and the other valves to be closed.

9. The method for dehydrating molecular sieves using photothermal energy according to claim 7, It is characterized in that When dehydration tower I (1) is in adsorption and dehydration tower II (2) is in regeneration heating, it is only necessary to control KV-1A valve, KV-2A valve, KV-7 valve, KV-4B valve, and KV-3B valve to open, and the other valves to close.

10. A molecular sieve dehydration method using photothermal energy according to claim 9, It is characterized in that When the dehydration tower I (1) adsorbs and the dehydration tower II (2) regenerates and heats up and then performs cold blowing, it is only necessary to control the KV-1A valve, KV-2A valve, KV-6 valve, KV-4B valve, and KV-3B valve to be opened, and the other valves to be closed.

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