An adsorbent gas cycle heating-cooling system

Abstract

The utility model provides a kind of adsorbent gas circulation heating-cooling system, it includes at least 2 adsorbent tanks of series connection, the top of each adsorbent tank is equipped with gas outlet, bottom is equipped with gas inlet, the gas outlet of adsorbent tank of upper stage is connected with the gas inlet of adsorbent tank of lower stage and constitutes series connection structure;The gas inlet of all adsorbent tanks is communicated with nitrogen main pipe by two ways, nitrogen heater is equipped on the pipeline of one way, valve one is equipped on nitrogen main pipe;The gas outlet of adsorbent tank of last stage is connected with the import of gas cooler, the export of gas cooler is communicated with atmosphere by valve six;Except last stage, the gas outlet of other adsorbent tank is also communicated with the import of nitrogen heater.The utility model can reasonably utilize nitrogen temperature by the on-off state of control valve, carries out cross cooling-heating, can reduce nitrogen emission, can also save heating energy consumption, shorten activation operation time, reach the purpose of energy saving and efficiency increasing.

Description

Technical Field

[0001] This utility model relates to an adsorbent gas circulation heating-cooling system, belonging to the field of chemical process heating-cooling technology. Background Technology

[0002] Adsorbents used in chemical processes typically require activation by heating before use. After activation at high temperatures, they are cooled to room temperature and used according to process requirements. For feeds with high impurity content, adsorbents are usually stored in several parallel containers, and their use is switched based on the adsorbent's deactivation status. Nitrogen is typically used as both a heat carrier and cooling medium for adsorbent activation. Companies with limited nitrogen production do not want to consume large amounts of nitrogen during adsorbent activation, which could disrupt the normal operation of other units. If a conventional series connection method is used, heating several adsorbent tanks together and then cooling them simultaneously after activation is employed, this approach is not only time-consuming and wasteful of nitrogen, but also fails to effectively recover heat. Therefore, optimizing the adsorbent activation process for switching between units, and making rational use of heat and nitrogen, is highly beneficial for energy conservation and efficiency improvement for companies. This optimized process can be applied not only to adsorbent activation but also to other similar situations. Summary of the Invention

[0003] The technical problem to be solved by this utility model is to provide an optimized process for adsorbent gas circulation heating-cooling.

[0004] To address the aforementioned technical problems, this utility model provides an adsorbent gas circulation heating-cooling system, comprising at least two adsorbent tanks connected in series. Each adsorbent tank has an outlet at the top and an inlet at the bottom. The outlet of the upper-level adsorbent tank is connected to the inlet of the lower-level adsorbent tank to form a series structure. The inlets of all adsorbent tanks are connected to a nitrogen main pipe via two paths, one of which is equipped with a nitrogen heater. A valve is installed on the nitrogen main pipe. The outlet of the last-stage adsorbent tank is connected to the inlet of a gas cooler, and the outlet of the gas cooler is connected to the atmosphere via a valve. Except for the last stage, the outlets of the other adsorbent tanks are also connected to the inlet of the nitrogen heater.

[0005] Preferably, valves are provided on all pipelines between the air inlet of each adsorbent tank and the nitrogen main pipe. Specifically, on pipelines equipped with nitrogen heaters, each adsorbent tank and the nitrogen heater is equipped with a valve, and the nitrogen heater and the nitrogen main pipe are equipped with a valve. On another pipeline without a nitrogen heater, each adsorbent tank and the nitrogen main pipe are equipped with a valve, and the pipeline and the nitrogen main pipe are equipped with a valve.

[0006] Preferably, a system pressure gauge is provided upstream of the inlet of the gas cooler.

[0007] Preferably, a nitrogen flow meter is provided on the nitrogen main pipe.

[0008] Preferably, a valve is provided between the outlet of any of the adsorbent tanks and the inlet of the next-stage adsorbent tank.

[0009] Preferably, the outlet of the gas cooler is also connected to the inlet of the gas recirculation compressor via valve fifteen, and the outlet of the gas recirculation compressor is connected to the nitrogen main pipe via valve sixteen. The hot nitrogen flowing out of the final stage adsorbent tank, after being cooled by the gas cooler, will circulate back to the inlet of the flow meter to form a closed loop if a recirculation compressor is present; otherwise, the cooled nitrogen will be directly vented.

[0010] More preferably, the nitrogen main pipe is also directly connected to the air inlet of each adsorbent tank through a valve, that is, without passing through a nitrogen heater.

[0011] Preferably, the number of adsorbent tanks is at least three.

[0012] After the adsorbent in the first-stage adsorbent tank is activated, cold nitrogen gas is introduced into the tank by opening the relevant valves to cool the adsorbent. The nitrogen gas, having recovered some heat, is returned to the nitrogen heater for reheating and then enters the next-stage adsorbent tank via a valve, and then the next-next-stage adsorbent tank, continuing to heat and activate the adsorbents in other adsorbent tanks.

[0013] When there are at least three adsorbent tanks, after the adsorbent in any n+1 stage adsorbent tank has been activated, if the n-stage adsorbent tank has not cooled to room temperature, open the valve between the outlet of the n-stage adsorbent tank and the inlet of the n+1 stage adsorbent tank, as well as the valve between the outlet of the n+1 stage adsorbent tank and the nitrogen heater, to cool the two adsorbent tanks in series. At the same time, close the valve between the outlet of the n-stage adsorbent tank and the nitrogen heater, and the valve between the outlet of the n+1 stage adsorbent tank and the inlet of the n+2 stage adsorbent tank. If the n-stage adsorbent tank has cooled to room temperature, close the valve between the inlet of the n-stage adsorbent tank and the nitrogen main pipe, as well as the valve between the outlet of the n-stage adsorbent tank and the nitrogen heater, to disconnect the n-stage adsorbent tank from the process. Open the valve between the inlet of the n+1 stage adsorbent tank and the nitrogen main pipe, and the valve between the outlet of the n+1 stage adsorbent tank and the nitrogen heater to directly cool the n+1 stage adsorbent tank. Open the valve between the nitrogen heater and the inlet of the n+2 stage adsorbent tank, and close the valve between the nitrogen heater and the inlets of the n-stage and n+1 stage adsorbent tanks. The heated nitrogen gas will only heat and activate the adsorbent in the n+2 stage adsorbent tank.

[0014] After the adsorbent activation in the final stage adsorbent tank is complete, if the previous stage adsorbent tank has not cooled to room temperature, open the valves between the inlet of the previous stage adsorbent tank and the nitrogen main pipe, and the valves between the inlet of the final stage adsorbent tank and the outlet of the previous stage adsorbent tank to cool these two adsorbent tanks in series. Simultaneously close the valves between the outlet of the previous stage adsorbent tank and the nitrogen heater, and the valves between the nitrogen heater and the inlet of the final stage adsorbent tank. If the previous stage adsorbent tank has already cooled to room temperature, close the valves between the inlet of the previous stage adsorbent tank and the nitrogen main pipe, the valves between the inlet of the final stage adsorbent tank and the outlet of the previous stage adsorbent tank, and the valves between the outlet of the previous stage adsorbent tank and the nitrogen heater to disconnect the previous stage adsorbent tank from the process. Open the valve between the inlet of the final stage adsorbent tank and the nitrogen main pipe to directly cool the final stage adsorbent tank, and simultaneously close the valve between the inlet of the final stage adsorbent tank and the nitrogen heater, stopping the nitrogen heater, until the adsorbent in the final stage adsorbent tank is cooled to room temperature.

[0015] The hot nitrogen gas flowing out of the final stage adsorbent tank is cooled by a gas cooler. If the nitrogen is not recycled, it is vented directly. If the nitrogen is recycled, it is returned to the first stage adsorbent tank for further cooling via a gas recirculation compressor. Valve two is closed, achieving optimized circulation of cold and hot nitrogen as required. The opening / closing of valve one depends on whether the nitrogen is recycled.

[0016] This invention utilizes nitrogen temperature for cross-cooling and heating by controlling the on / off state of the valve. This reduces nitrogen emissions, saves heating energy, and shortens activation time, achieving energy conservation and efficiency. This invention can be used not only for activating adsorbents but also for other similar applications. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the adsorbent gas circulation heating-cooling system provided in the embodiment. Detailed Implementation

[0018] To make this utility model more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings.

[0019] Example

[0020] like Figure 1As shown, this embodiment provides an adsorbent gas circulation heating-cooling system, which includes three adsorbent tanks connected in series. Each adsorbent tank has an outlet at the top and an inlet at the bottom. The outlet of the upper-level adsorbent tank is connected to the inlet of the lower-level adsorbent tank to form a series structure, namely, adsorbent tank 1 (3), adsorbent tank 2 (4), and adsorbent tank 3 (5). The outlet of adsorbent tank 1 (3) is connected to the inlet of adsorbent tank 2 (4) through valve 4 (8-4), and the outlet of adsorbent tank 2 (4) is connected to the inlet of adsorbent tank 3 (5) through valve 5 (8-5).

[0021] All adsorbent tanks have two inlets connected to the nitrogen main pipe. One inlet is directly connected to the nitrogen main pipe via a pipe and valve, while the other inlet is connected to the nitrogen main pipe via a pipe, valve, and nitrogen heater 2. A nitrogen flow meter 1 is installed on the nitrogen main pipe. The inlet of nitrogen flow meter 1 is connected to ambient temperature nitrogen via valve 1 (8-1). The outlet of nitrogen flow meter 1 is connected to valves 2 (8-2) and 7 (8-7). The outlet of valve 7 (8-7) is connected to the inlets of adsorbent tank 1 (3), adsorbent tank 2 (4), and adsorbent tank 3 (5) via valves 8 (8-8), 12 (8-12), and 14 (8-14). The outlet of valve 2 (8-2) is connected to the inlet of nitrogen heater 2. The outlet of nitrogen heater 2 is connected to the inlets of adsorbent tank 1 (3), adsorbent tank 2 (4), and adsorbent tank 3 (5) via valves 3 (8-3), 10 (8-10), and 13 (8-13). The outlets of adsorbent tank 1 (3) and adsorbent tank 2 (4) are also connected to the inlet of nitrogen heater 2 via valve 9 (8-9) and valve 11 (8-11), respectively.

[0022] The outlet of adsorbent tank 35 is connected to the inlet of gas cooler 8, and a system pressure gauge 6 is installed on the pipeline between them. The outlet of gas cooler 8 is directly vented through valve 6 8-6. A gas circulation compressor can also be added to recycle nitrogen in the system. The outlet of gas cooler 8 is connected to the inlet of gas circulation compressor 7 through valve 15 8-15, and the outlet of gas circulation compressor 7 is connected to the inlet of nitrogen flow meter 1 through valve 16 8-16.

[0023] The operation process of the above system is as follows:

[0024] The first step is the heating stage of three adsorbent tanks connected in series:

[0025] Compressorless process: Fresh nitrogen → Valve 1 (8-1) → Nitrogen flow meter 1 → Valve 2 (8-2) → Nitrogen heater 2 → Valve 3 (8-3) → Adsorbent tank 1 (3) → Valve 4 (8-4) → Adsorbent tank 2 (4) → Valve 5 (8-5) → Adsorbent tank 3 (5) → Gas cooler 8 → Valve 6 (8-6) → Vent. All other valves are closed.

[0026] The compressor flow is as follows: Gas recirculation compressor 7 → Valve 16 (8-16) → Nitrogen flow meter 1 → Valve 2 (8-2) → Nitrogen heater 2 → Valve 3 (8-3) → Adsorbent tank 1 (3) → Valve 4 (8-4) → Adsorbent tank 2 (4) → Valve 5 (8-5) → Adsorbent tank 3 (5) → Gas cooler 8 → Valve 15 (8-15) → Gas recirculation compressor 7. All other valves are closed.

[0027] The nitrogen gas required for adsorbent activation, at room temperature, is metered by nitrogen flow meter 1 and then enters nitrogen heater 2 to heat the nitrogen. The heated nitrogen gas sequentially enters adsorbent tank 1 (3), adsorbent tank 2 (4), and adsorbent tank 3 (5). After exiting adsorbent tank 3 (5), the nitrogen gas enters gas cooler 8 to cool it down. If there is no circulating compressor, valve 6 (8-6) is opened to directly vent the nitrogen, ensuring a continuous supply of fresh nitrogen to the system. If there is a compressor, valves 15 (8-15) and 16 (8-16) are opened, using gas circulating compressor 7 to pressurize and circulate the nitrogen. Once the nitrogen in the system is ready for circulation, valve 1 (8-1) is closed to stop supplying fresh nitrogen to the system. The adsorbent activation is achieved solely through repeated heating and cooling of the circulating nitrogen. The three adsorbent tanks are heated in series until adsorbent tank 3 reaches the required temperature and completes isothermal activation.

[0028] The second step involves the cooling of adsorbent tank 1 (3) and the series heating of adsorbent tank 2 (4) and adsorbent tank 3 (5).

[0029] When adsorbent tank 1 (3) completes the activation process, adsorbent tanks 2 (4) and 3 (5) may not yet have reached the required activation temperature. To effectively utilize heat and reduce nitrogen emissions, the cooling of adsorbent tank 1 (3) and the heating of adsorbent tanks 2 (4) and 3 (5) are performed alternately. The process flow is as follows:

[0030] Compressorless process: Fresh nitrogen → Valve 1 (8-1) → Nitrogen flow meter 1 → Valve 7 (8-7) → Valve 8 (8-8) → Adsorbent tank 1 (3) → Valve 9 (8-9) → Nitrogen heater 2 → Valve 10 (8-10) → Adsorbent tank 2 (4) → Valve 5 (8-5) → Adsorbent tank 3 (5) → Gas cooler 8 → Valve 6 (8-6) → Vent. Other valves are closed.

[0031] The compressor flow is as follows: Gas recirculation compressor 7 → Valve 16 (8-16) → Nitrogen flow meter 1 → Valve 7 (8-7) → Valve 8 (8-8) → Adsorbent tank 1 (3) → Valve 9 (8-9) → Nitrogen heater 2 → Valve 10 (8-10) → Adsorbent tank 2 (4) → Valve 5 (8-5) → Adsorbent tank 3 (5) → Gas cooler 8 → Valve 15 (8-15) → Gas recirculation compressor 7, forming a closed loop. All other valves are closed.

[0032] Without a compressor, fresh, room-temperature nitrogen gas is metered by flow meter 1 and enters adsorbent tank 3 to cool the activated adsorbent. The nitrogen gas, having recovered some heat, exits adsorbent tank 3 and enters nitrogen heater 2 for further heating. It then sequentially enters adsorbent tank 4 and adsorbent tank 5, continuing the heating process in each. Nitrogen gas exiting from the top of adsorbent tank 5 is cooled by gas cooler 8 and then vented. This process continues until the adsorbent in adsorbent tank 4 reaches the required temperature, completing the isothermal activation.

[0033] With a compressor, circulating cold nitrogen gas is metered by flow meter 1 and then enters adsorbent tank 3 to cool the activated adsorbent. The remaining operations are the same as without a compressor. Finally, the nitrogen gas flowing out from the top of adsorbent tank 5 is cooled by gas cooler 8 and then not vented, but instead pressurized by gas recirculation compressor 7 and recycled.

[0034] The third step involves cooling of adsorbent tank 1 (3) and adsorbent tank 2 (4), and heating of adsorbent tank 3 (5).

[0035] When adsorbent tank 2 (4) completes the activation process, adsorbent tank 3 (5) may not have reached the required activation temperature. Furthermore, adsorbent tank 1 (3) may or may not have reached room temperature. If adsorbent tank 1 (3) has reached room temperature, it is removed from the cooling process. If adsorbent tank 1 (3) has not yet reached room temperature, adsorbent tanks 1 (3) and 2 (4) are connected in series for continued cooling. To effectively utilize heat and reduce nitrogen emissions, the cooling of adsorbent tanks 1 (3) and 2 (4) and the heating of adsorbent tank 3 (5) are performed alternately. The process flow is as follows:

[0036] No compressor flow (adsorbent tank 1-3 not cooled to room temperature): Fresh nitrogen → Valve 1-8-1 → Nitrogen flow meter 1 → Valve 7-8-7 → Valve 8-8 → Adsorbent tank 1-3 → Valve 4-4 → Adsorbent tank 2-4 → Valve 11-8-11 → Nitrogen heater 2 → Valve 13-8-13 → Adsorbent tank 3-5 → Gas cooler 8 → Valve 6-8-6 → Vent. Other valves are closed.

[0037] Compressorless process (adsorbent tank 1-3 has cooled to room temperature): Fresh nitrogen → Valve 1-8-1 → Nitrogen flow meter 1 → Valve 7-8-7 → Valve 12-8-12 → Adsorbent tank 2-4 → Valve 11-8-11 → Nitrogen heater 2 → Valve 13-8-13 → Adsorbent tank 3-5 → Gas cooler 8 → Valve 6-8-6 → Vent. Other valves are closed.

[0038] The compressor flow (adsorbent tank 1-3 not cooled to room temperature) is as follows: Gas circulation compressor 7 → Valve 16 (8-16) → Nitrogen flow meter 1 → Valve 7 (8-7) → Valve 8 (8-8) → Adsorbent tank 1-3 → Valve 4 (8-4) → Adsorbent tank 2 (4) → Valve 11 (8-11) → Nitrogen heater 2 → Valve 13 (8-13) → Adsorbent tank 3 (5) → Gas cooler 8 → Valve 15 (8-15) → Gas circulation compressor 7, forming a closed loop. All other valves are closed.

[0039] The compressor flow (adsorbent tank 1-3 has been cooled to room temperature) is as follows: Gas circulation compressor 7 → Valve 16 8-16 → Nitrogen flow meter 1 → Valve 7 8-7 → Valve 12 8-12 → Adsorbent tank 2 4 → Valve 11 8-11 → Nitrogen heater 2 → Valve 13 8-13 → Adsorbent tank 3 5 → Gas cooler 8 → Valve 15 8-15 → Gas circulation compressor 7, forming a closed loop. All other valves are closed.

[0040] Without a circulating compressor, when the activation of adsorbent tank 2 (4) is complete, if adsorbent tank 1 (3) has not yet cooled to room temperature, fresh room temperature nitrogen gas, after metering, is sequentially introduced into adsorbent tank 1 (3) and adsorbent tank 2 (4) in series for cooling. If adsorbent tank 1 (3) has already cooled to room temperature, it is removed from the process. Fresh room temperature nitrogen gas, after metering, directly enters adsorbent tank 2 (4) to cool the adsorbent therein, recovering some heat, and then returns to nitrogen heater 2 for supplemental heating before entering adsorbent tank 3 (5) to continue heating and activating the adsorbent therein. The hot nitrogen gas exiting adsorbent tank 3 (5) is vented after cooling. This process is maintained until adsorbent tank 3 (5) reaches the required temperature and completes isothermal activation.

[0041] With a circulating compressor, since the nitrogen flowing out of adsorbent tank 35 is not vented, no fresh nitrogen supply is required, and other operations are the same as without a compressor.

[0042] Step 4, Cooling stage of Adsorbent Tank 2 (4) and Adsorbent Tank 3 (5):

[0043] When adsorbent tank 3 (5) completes the activation process, if adsorbent tank 2 (4) has cooled to room temperature, it should be removed from the cooling process. If adsorbent tank 2 (4) has not yet cooled to room temperature, it should be connected in series with adsorbent tank 3 (5) for simultaneous cooling. The adjustment process is as follows:

[0044] No compressor flow (adsorbent tank 2, 4 not cooled to room temperature): Fresh nitrogen → Valve 1, 8-1 → Nitrogen flow meter 1 → Valve 7, 8-7 → Valve 12, 8-12 → Adsorbent tank 2, 4 → Valve 5, 8-5 → ​​Adsorbent tank 3, 5 → Gas cooler 8 → Valve 6, 8-6 → Vent. Other valves are closed.

[0045] Compressorless process (adsorbent tank 2, 4 has cooled to room temperature): Fresh nitrogen → Valve 1, 8-1 → Nitrogen flow meter 1 → Valve 7, 8-7 → Valve 14, 8-14 → Adsorbent tank 3, 5 → Gas cooler 8 → Valve 6, 8-6 → Vent. Other valves are closed.

[0046] The compressor flow (adsorbent tank 2, 4 not cooled to room temperature) is as follows: Gas circulation compressor 7 → Valve 16 (8-16) → Nitrogen flow meter 1 → Valve 7 (8-7) → Valve 12 (8-12) → Adsorbent tank 2, 4 → Valve 5 (8-5) → Adsorbent tank 3, 5 → Gas cooler 8 → Valve 15 (8-15) → Gas circulation compressor 7, forming a closed loop. All other valves are closed.

[0047] The compressor flow (adsorbent tank 2, 4 has been cooled to room temperature) is as follows: Gas circulation compressor 7 → Valve 16 (8-16) → Nitrogen flow meter 1 → Valve 7 (8-7) → Valve 14 (8-14) → Adsorbent tank 3 (5) → Gas cooler 8 → Valve 15 (8-15) → Gas circulation compressor 7, forming a closed loop. Other valves are closed.

[0048] Without a circulating compressor, when the activation of adsorbent tank 3 (5) is complete, if adsorbent tank 2 (4) has not yet cooled to room temperature, fresh room temperature nitrogen gas, after being metered, is sequentially introduced into adsorbent tank 2 (4) and adsorbent tank 3 (5) in series for cooling. If adsorbent tank 2 (4) has already cooled to room temperature, it is disconnected from the process, and fresh room temperature nitrogen gas, after being metered, is used to cool the adsorbent in adsorbent tank 3 (5) separately. The nitrogen gas flowing out of adsorbent tank 3 (5) is cooled and vented.

[0049] With a circulating compressor, since the nitrogen flowing out of adsorbent tank 35 is not vented, no fresh nitrogen supply is required, and other operations are the same as without a circulating compressor.

[0050] Without a compressor to recycle the discharged nitrogen, a significant amount of nitrogen is wasted; however, adding a compressor requires additional equipment investment. Therefore, the specific process to be adopted needs to be determined through a comprehensive evaluation of the economics of both scenarios. Regardless of whether nitrogen is recycled, the optimized cross-heating and cooling process, due to its rational use of nitrogen temperature—that is, using room-temperature nitrogen to cool the adsorbent that needs cooling, and then using the recovered hot nitrogen as a heating medium for the adsorbent that needs heating—shortens the overall activation time of the adsorbent, reduces nitrogen emissions, and lowers heating energy consumption.

Claims

1. An adsorbent gas circulation heating-cooling system, characterized in that, It includes at least two adsorbent tanks connected in series. Each adsorbent tank has an outlet at the top and an inlet at the bottom. The outlet of the adsorbent tank of the previous stage is connected to the inlet of the adsorbent tank of the next stage to form a series structure. The inlets of all adsorbent tanks are connected to the nitrogen main pipe through two paths. One of the paths is equipped with a nitrogen heater (2). The nitrogen main pipe is equipped with valve one (8-1). The outlet of the last stage adsorbent tank is connected to the inlet of the gas cooler (8). The outlet of the gas cooler (8) is connected to the atmosphere through valve six (8-6). Except for the last stage, the outlets of the other adsorbent tanks are also connected to the inlet of the nitrogen heater (2).

2. The adsorbent gas circulation heating-cooling system as described in claim 1, characterized in that, Valves are installed on all pipelines between the air inlet of each adsorbent tank and the nitrogen main.

3. The adsorbent gas circulation heating-cooling system as described in claim 1, characterized in that, The gas cooler (8) is equipped with a system pressure gauge (6) upstream of its inlet.

4. The adsorbent gas circulation heating-cooling system as described in claim 1, characterized in that, A nitrogen flow meter (1) is installed on the nitrogen main pipe.

5. The adsorbent gas circulation heating-cooling system as described in claim 1, characterized in that, A valve is provided between the outlet of any of the adsorbent tanks and the inlet of the next-stage adsorbent tank.

6. The adsorbent gas circulation heating-cooling system as described in claim 1, characterized in that, The outlet of the gas cooler (8) is also connected to the inlet of the gas circulation compressor (7) through valve fifteen (8-15), and the outlet of the gas circulation compressor (7) is connected to the nitrogen main pipe through valve sixteen (8-16).

7. The adsorbent gas circulation heating-cooling system as described in claim 1, characterized in that, The number of adsorbent tanks is at least three.

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