A process for simultaneous desorption of a rotating wheel and a fixed bed

Abstract

The present invention relates to the technical field of flue gas recovery, and particularly to a process for simultaneous desorption of a rotating wheel and a fixed bed. The inlet end of the adsorption zone of the concentrator rotating wheel is connected to a waste gas source I, the exhaust end of the adsorption zone of the concentrator rotating wheel is connected to an exhaust main pipe, the outlet end of the desorption zone of the concentrator rotating wheel is connected to the inlet end of a mixing air box I, the outlet end of the mixing air box I is connected to the third inlet pipe of an incinerator, the third exhaust pipe of the incinerator is connected to the inlet end of a mixing air box II, the outlet end of the mixing air box II is connected to the first inlet pipe of an activated carbon adsorber, the first exhaust pipe of the activated carbon adsorber is connected to the inlet end of the mixing air box I, the second inlet pipe of the activated carbon adsorber is connected to a waste gas source II, and the second exhaust pipe of the activated carbon adsorber is connected to the exhaust main pipe. The present invention realizes the simultaneous desorption of the activated carbon in the activated carbon adsorber and the concentrator rotating wheel through an incinerator.

Description

Technical Field

[0001] This invention patent relates to the technical field of flue gas recovery, and specifically relates to a process for simultaneous desorption of a rotating wheel and a fixed bed. Background Art

[0002] The painting lines in surface coating industries such as those for electric vehicles and automobile bodies generally consist of three steps: First step, intermediate coating spraying, leveling, and drying; Second step, basecoat spraying, leveling, and drying; Third step, clearcoat spraying, leveling, and drying.

[0003] In the first and second steps, waterborne paints are generally used in the painting booths, with relatively low VOC concentrations, and are treated by the method of activated carbon adsorption + CO catalytic oxidation furnace desorption. In the third step, oil-based paints are generally used, with relatively high VOC concentrations, and need to be treated by the method of rotating wheel concentration + RTO / RCO regenerative oxidation / regenerative catalytic oxidation; Although the two systems operate simultaneously, the control and pipelines are relatively independent. At most, they share one chimney for evacuation. The exhaust gas from the three-process drying room is collected separately, with a small air volume and a high temperature, and generally enters the RTO directly.

[0004] However, during the desorption process of activated carbon adsorption + CO catalytic oxidation furnace in the first and second steps, the initial investment of the CO furnace as a single device is relatively large, it occupies a large space, and a large amount of energy (electricity, gas) is consumed during operation; In the third step, when using the rotating wheel concentration + RTO / RCO regenerative oxidation / regenerative catalytic oxidation technology, the outlet temperature of the RTO furnace is 70 - 130 °C, resulting in heat waste. Summary of the Invention

[0005] The present invention proposes a system for simultaneous desorption of a rotating wheel and a fixed bed.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A desorption system for a rotating wheel and a fixed bed, comprising a concentrator rotating wheel, an incinerator and an activated carbon adsorber. The intake end of the adsorption zone of the concentrator rotating wheel is connected to a waste gas source I, the exhaust end of the adsorption zone of the concentrator rotating wheel is connected to an exhaust main pipe, the outlet end of the desorption zone of the concentrator rotating wheel is connected to the intake end of a mixing box I, the outlet end of the mixing box I is connected to the third intake pipe of the incinerator, the third exhaust pipe of the incinerator is connected to the intake end of a mixing box II, the outlet end of the mixing box II is connected to the first intake pipe of the activated carbon adsorber, the first exhaust pipe of the activated carbon adsorber is connected to the intake end of the mixing box I, the second intake pipe of the activated carbon adsorber is connected to a waste gas source II, the second exhaust pipe of the activated carbon adsorber is connected to the exhaust main pipe, the upper part of the incinerator is connected to one end of a connecting pipe II, the other end of the connecting pipe II is connected to the intake end of the mixing box II, a connecting pipe III is arranged on the intake end of the mixing box II, the connecting pipe III is connected to an air source, a control valve I is installed on the connecting pipe III, a control valve II is installed on the connecting pipe II, a flow sensor III and a temperature sensor III are installed at the intake end where the mixing box II is connected to the third exhaust pipe of the incinerator, a flow sensor I and a temperature sensor I are installed at the intake end where the mixing box II is connected to the connecting pipe II, a flow sensor IV and a temperature sensor IV are installed at the intake end where the mixing box II is connected to the first intake pipe, and a flow sensor II and a temperature sensor II are arranged at the intake end where the mixing box II is connected to the connecting pipe III.

[0008] Further, the first exhaust pipe of the activated carbon adsorber is connected to an exhaust collecting pipe I, and a fan III is installed on the exhaust collecting pipe I.

[0009] Further, the second exhaust pipe of the activated carbon adsorber is connected to an exhaust collecting pipe II, and the exhaust collecting pipe II is connected to a fan IV.

[0010] Further, the first intake pipe of the activated carbon adsorber is connected to an intake collecting pipe I, the intake collecting pipe I is connected to one end of a control valve V, the other end of the control valve V is connected to a connecting pipe IV, the connecting pipe IV is connected to the intake end of the mixing box II, the connecting pipe IV is connected to an exhaust pipe IV, the other end of the exhaust pipe IV is connected to the exhaust main pipe, and a control valve IV is installed on the exhaust pipe IV.

[0011] Further, the waste gas source II is divided into two parts. One part enters the activated carbon adsorber through the second intake pipe after being filtered by a filter III, and the other part enters a filter II for filtration. The outlet end of the filter II is connected to a connecting pipe V and a connecting pipe VI. A control valve VI is installed on the connecting pipe V, a control valve III is installed on the connecting pipe VI. The connecting pipe V is connected to a mixing box I, and the connecting pipe VI is connected to the intake end of the filter III.

[0012] Further, the exhaust end of the adsorption zone of the concentrator wheel is connected to the first fan, the air outlet end of the first fan is connected to the exhaust main pipe, and the exhaust main pipe is connected to the chimney.

[0013] Further, a first switching valve is installed on the first exhaust pipe of the activated carbon adsorber, a second switching valve is installed on the first intake pipe, a third switching valve is installed on the second intake pipe, and a fourth switching valve is installed on the second exhaust pipe.

[0014] Further, the desorption intake end of the concentrator wheel is connected to the outlet end of the tube side of the heat exchanger, the outlet end of the cooling zone of the concentrator wheel is connected to the intake end of the tube side of the heat exchanger, the intake end of the shell side of the heat exchanger is connected to one end of the first connecting pipe, the other end of the first connecting pipe is connected to the upper end of the incinerator, and the outlet end of the shell side of the heat exchanger is connected to the exhaust main pipe.

[0015] Further, a second fan is installed between the air outlet end of the first air mixing box and the third intake pipe of the incinerator.

[0016] Advantages: The present invention realizes the simultaneous desorption of the activated carbon in the activated carbon adsorber and the concentrator wheel through the incinerator. Description of the Drawings

[0017] Figure 1 is the overall schematic diagram of the present invention;

[0018] Figure 2 is the structural schematic diagram of the second air mixing box in the present invention;

[0019] Figure 3 is the structural schematic diagram of the activated carbon adsorber in the present invention.

[0020] In the figure: 1 first filter, 2 concentrator wheel, 3 first fan, 4 first air mixing box, 5 second fan, 6 incinerator, 7 second air mixing box, 8 first control valve, 9 second control valve, 10 second filter, 11 sixth control valve, 12 third control valve, 13 third filter, 14 activated carbon adsorber, 15 third fan, 16 fourth fan, 17 fourth control valve, 18 fifth control valve, 19 heat exchanger, 20 first waste gas source, 21 second waste gas source, 22 chimney, 23 first connecting pipe, 24 second connecting pipe;

[0021] 401 first exhaust pipe, 402 first exhaust collecting pipe, 403 second exhaust pipe, 404 second exhaust collecting pipe, 405 first intake pipe, 406 first intake collecting pipe, 407 second intake pipe, 408 first switching valve, 409 second switching valve, 410 third switching valve, 411 fourth switching valve;

[0022] 601 third intake pipe, 602 third exhaust pipe;

[0023] Flow sensor 1 of 701, temperature sensor 1 of 702, flow sensor 2 of 703, temperature sensor 2 of 704, flow sensor 3 of 705, temperature sensor 3 of 706, flow sensor 4 of 707, temperature sensor 4 of 708. Detailed implementation mode

[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0025] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and 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 should not be construed as a limitation to the present invention.

[0026] Refer to Figure 1As shown in Fig. –3, a simultaneous desorption system for a rotating wheel and a fixed bed in the present invention includes a concentrator rotating wheel 2, an incinerator 6, and an activated carbon adsorber 14. The intake end of the adsorption zone of the concentrator rotating wheel 2 is connected to a waste gas source 1, and the exhaust end of the adsorption zone of the concentrator rotating wheel 2 is connected to an exhaust main pipe. The outlet end of the desorption zone of the concentrator rotating wheel 2 is connected to the intake end of a mixing air box 1, and the outlet end of the mixing air box 1 is connected to the third intake pipe 601 of the incinerator 6. The third exhaust pipe 602 of the incinerator 6 is connected to the intake end of a mixing air box 2, and the outlet end of the mixing air box 2 is connected to the first intake pipe 405 of the activated carbon adsorber 14. The first exhaust pipe 401 of the activated carbon adsorber 14 is connected to the intake end of the mixing air box 1. The second intake pipe 407 of the activated carbon adsorber 14 is connected to a waste gas source 2, and the second exhaust pipe 403 of the activated carbon adsorber 14 is connected to the exhaust main pipe. The upper part of the incinerator 6 is connected to one end of a second connecting pipe 24, and the other end of the second connecting pipe 24 is connected to the intake end of the mixing air box 2. A third connecting pipe is provided at the intake end of the mixing air box 2, and the third connecting pipe is connected to an air source. A first control valve 8 is installed on the third connecting pipe, and a second control valve 9 is installed on the second connecting pipe 24. A third flow sensor 705 and a third temperature sensor 706 are installed at the intake end of the mixing air box 2 where it is connected to the third exhaust pipe 602 of the incinerator 6. A first flow sensor 701 and a first temperature sensor 702 are installed at the intake end of the mixing air box 2 where it is connected to the second connecting pipe 24. A fourth flow sensor 707 and a fourth temperature sensor 708 are installed at the intake end of the mixing air box 2 where it is connected to the first intake pipe 405. A second flow sensor 703 and a second temperature sensor 704 are installed at the intake end of the mixing air box 2 where it is connected to the third connecting pipe. The first exhaust pipe 401 of the activated carbon adsorber 14 is connected to a first exhaust collecting pipe 402, and a third fan 15 is installed on the first exhaust collecting pipe 402. The second exhaust pipe 403 of the activated carbon adsorber 14 is connected to a second exhaust collecting pipe 404, and the second exhaust collecting pipe 404 is connected to a fourth fan 16.

[0027] The first intake pipe 405 of the activated carbon adsorber 14 is connected to a first intake collecting pipe 406, the first intake collecting pipe 406 is connected to one end of a fifth control valve 18, the other end of the fifth control valve 18 is connected to a fourth connecting pipe, the fourth connecting pipe is connected to the intake end of the mixing air box 2, the fourth connecting pipe is connected to a fourth exhaust pipe, the other end of the fourth exhaust pipe is connected to the exhaust main pipe, and a fourth control valve 17 is installed on the fourth exhaust pipe.

[0028] The exhaust gas source two 21 is divided into two parts. One part passes through the filter three 13 and then enters the activated carbon adsorber 14 through the intake pipe two 407. The other part enters the filter two 10 for filtration. The outlet end of the filter two 10 is connected to the connecting pipe five and the connecting pipe six. A control valve six 11 is installed on the connecting pipe five, and a control valve three 12 is installed on the connecting pipe six. The connecting pipe five is connected to the mixing box one, and the connecting pipe six is connected to the intake end of the filter three 13. The exhaust gas source two includes primer painting, leveling, drying in the first step and topcoat spraying, leveling, drying in the second step. The exhaust gas source one includes clear coat spraying, leveling, drying in the third step.

[0029] The exhaust end of the adsorption zone of the concentrator wheel 2 is connected to the fan one 3. The outlet end of the fan one 3 is connected to the exhaust main pipe, and the exhaust main pipe is connected to the chimney 22. A switching valve one 408 is installed on the exhaust pipe one 401 of the activated carbon adsorber 14, a switching valve two 409 is installed on the intake pipe one 405, a switching valve three 410 is installed on the intake pipe two 407, and a switching valve four 411 is installed on the exhaust pipe two 403.

[0030] The desorption intake end of the concentrator wheel 2 is connected to the outlet end of the tube side of the heat exchanger 19. The outlet end of the cooling zone of the concentrator wheel 2 is connected to the intake end of the tube side of the heat exchanger 19. The intake end of the shell side of the heat exchanger 19 is connected to one end of the connecting pipe one 23, and the other end of the connecting pipe one 23 is connected to the upper end of the incinerator 6. The outlet end of the shell side of the heat exchanger 19 is connected to the exhaust main pipe. A fan two 5 is installed between the outlet end of the mixing box one 4 and the intake pipe three 601 of the incinerator 6.

[0031] The outlet end of the cooling zone of the concentrator wheel 2 enters the heat exchanger 19 to exchange heat with the hot gas led out from the incinerator 6, and then enters the desorption zone intake end of the concentrator wheel 2 to desorb the concentrator wheel 2. The desorbed gas enters the mixing box one 4. The hot gas led out from the incinerator 6 is discharged into the exhaust main pipe after heat exchange in the heat exchanger 19.

[0032] The present invention provides an embodiment, a process for simultaneous desorption of a rotating wheel and a fixed bed. When the outlet detector of the activated carbon adsorber 14 indicates the corresponding design value or the time accumulation module of the activated carbon adsorber 14 indicates the adsorption time, the switching control valve six 11 of the waste gas source two 21 is closed and the control valve three 12 is opened, and the activated carbon adsorber 14 starts to be desorbed by the incinerator. The activated carbon adsorbers 14 in the system start to be desorbed in sequence from left to right. During desorption, the switching valve three 410 of the second intake pipe 407 of one of the activated carbon adsorbers 14 is closed, the switching valve four 411 of the second exhaust pipe 403 is closed, the switching valve two 409 of the first intake pipe 405 is opened, and the switching valve one 408 of the first exhaust pipe 401 is opened. The fan three 15 is started. The third exhaust pipe 602 of the incinerator 6 and the connecting pipe two 24 discharge the gas after heating and oxidation in the incinerator 6 into the mixing air box two 7, and enter the activated carbon adsorber 14 through the fourth connecting pipe, the first intake collecting pipe 406 and the first intake pipe 405 of the mixing air box two 7. At this time, the control valve five 18 on the fourth connecting pipe is in the open state. When the air volume in the fourth connecting pipe is too large, the control valve four 17 on the fourth exhaust pipe can be opened, and part of the gas in the fourth connecting pipe is discharged from the exhaust main pipe through the fourth exhaust pipe to desorb the activated carbon in the activated carbon adsorber 14. Finally, it enters the first exhaust collecting pipe 402 from the first exhaust pipe 401 at the bottom of the activated carbon adsorber 14. The desorbed gas enters the mixing air box one 4 under the action of the fan three 15. The mixing air box one 4 mixes the gas desorbed from the concentrating rotating wheel 2 and the gas desorbed from the activated carbon adsorber 14, and enters the incinerator 6 through the third intake pipe 601 under the action of the fan two 5 for incineration and oxidation. After one activated carbon adsorber 14 is desorbed, the switching valve three 410 of the second intake pipe 407 of this activated carbon adsorber 14 is opened, the switching valve four 411 of the second exhaust pipe 403 is opened, the switching valve two 409 of the first intake pipe 405 is closed, and the switching valve one 408 of the first exhaust pipe 401 is closed. Then, the switching valve three 410 of the second intake pipe 407 of another activated carbon adsorber 14 is closed, the switching valve four 411 of the second exhaust pipe 403 is closed, the switching valve two 409 of the first intake pipe 405 is opened, and the switching valve one 408 of the first exhaust pipe 401 is opened, and then this activated carbon adsorber 14 is desorbed. The cycle is carried out until all the activated carbon adsorbers 14 are completely desorbed, the control valve six 11 is opened, and the control valve three 12 is closed, and the system normally adsorbs waste gas.

[0033] The waste gas source one 20 enters the adsorption zone of the concentrating rotating wheel 2 after being filtered by the filter one 1, and finally is discharged from the chimney 22 through the action of the fan one 3 and the exhaust main pipe.

[0034] For the remaining activated carbon adsorbers 14, the switching valve three 410 of the second intake pipe 407 is opened, the switching valve four 411 of the second exhaust pipe 403 is opened, the switching valve two 409 of the first intake pipe 405 is closed, and the switching valve one 408 of the first exhaust pipe 401 is closed. During adsorption, the waste gas source two 21 enters the activated carbon adsorber 14 through the second intake pipe 407 after being filtered by the filter three 13, enters the activated carbon adsorber 14, is adsorbed by the internal activated carbon, and is discharged through the second exhaust pipe 403 at the upper part of the activated carbon adsorber 14 and the exhaust manifold, and is discharged through the chimney 22 under the action of the fan four 16.

[0035] When desorption is not required, the control valve five 18 on the fourth connecting pipe is in the closed state, and the control valve four 17 on the fourth exhaust pipe is in the open state. The gas discharged from the incinerator 6 enters the exhaust manifold through the exhaust pipe and is discharged.

[0036] When the activated carbon adsorber 14 is desorbed, the opening degrees of the control valve one 8 and the control valve two 9 are adjusted to adjust the temperature of the gas entering the fourth connecting pipe. The adjustment method is to adjust by increasing or decreasing the amount of normal temperature air entering the second mixing box 7. The specific adjustment formula is:

[0037] Q3 = (Q1(1 - T 目标 / T1) + Q2(1 - T 目标 / T2)) / (T 目标 / T3 - 1)

[0038] The data measured by the first flow sensor 701 is Q1, and the data measured by the first temperature sensor 702 is T1.

[0039] The data measured by the second flow sensor 703 is Q2, and the data measured by the second temperature sensor 704 is T2.

[0040] The data measured by the third flow sensor 705 is Q3, and the data measured by the third temperature sensor 706 is T3.

[0041] The data measured by the fourth flow sensor 707 is Qmix, and the data measured by the fourth temperature sensor 708 is Tmix;

[0042] By the real-time detection of the gas temperature Tmix at the outlet end of the second mixing box 7 by the fourth temperature sensor 708, comparing Tmix with the target desorption temperature T 目标 of the activated carbon adsorber 14, when Tmix > T 目标 , the system increases the opening degree of the control valve one 8, and when Tmix < T 目标 , the system decreases the opening degree of the control valve one 8.

[0043] The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent substitutions or changes, shall be covered by the protection scope of the present invention.

Claims

1. A process for simultaneous desorption of a rotating wheel and a fixed bed, characterized in that: When the outlet detector of the activated carbon adsorber indicates the corresponding design value or the time accumulation module of the activated carbon adsorber indicates that the adsorption time has been reached, the exhaust gas source two switching control valve six closes and the control valve three opens. The activated carbon adsorber starts to be desorbed using the incinerator. The activated carbon adsorbers in the system are desorbed sequentially from left to right. During desorption, the switching valve three of the second intake pipe of one of the activated carbon adsorbers closes, the switching valve four of the second exhaust pipe closes, the switching valve two of the first intake pipe opens, and the switching valve one of the first exhaust pipe opens. The fan three starts. The third exhaust pipe of the incinerator and the connecting pipe two discharge the gas heated and oxidized in the incinerator into the mixing air box two. It enters the activated carbon adsorber through the connecting pipe four, the intake air collecting pipe one and the first intake pipe of the mixing air box two. At this time, the control valve five on the connecting pipe four is in the open state. When the air volume in the connecting pipe four is too large, the control valve four on the exhaust pipe four is opened, and part of the gas in the connecting pipe four is discharged from the exhaust main pipe through the exhaust pipe four to desorb the activated carbon in the activated carbon adsorber. According to the optimal adsorption temperature T of the activated carbon in the activated carbon adsorber 目标 , the amount of normal temperature air entering the mixing air box two is adjusted by adjusting the opening degree of the control valve one on the connecting pipe three. The specific calculation formula is: Q3 = (Q1(1 - T 目标 / T1) + Q2(1 - T 目标 / T2)) / (T 目标 / T3 - 1); Finally, it enters the exhaust air collecting pipe one from the first exhaust pipe at the bottom of the activated carbon adsorber. The desorbed gas enters the mixing air box one under the action of the fan three. The gas desorbed by the concentrator wheel and the gas desorbed by the activated carbon adsorber are mixed in the mixing air box one and enter the incinerator for incineration oxidation under the action of the fan two. After one activated carbon adsorber is desorbed, the switching valve three of the second intake pipe of this activated carbon adsorber is opened, the switching valve four of the second exhaust pipe is opened, the switching valve two of the first intake pipe is closed, and the switching valve one of the first exhaust pipe is closed. Then the switching valve three of the second intake pipe of another activated carbon adsorber is closed, the switching valve four of the second exhaust pipe is closed, the switching valve two of the first intake pipe is opened, and the switching valve one of the first exhaust pipe is opened. Then this activated carbon adsorber is desorbed. The cycle continues until all the activated carbon adsorbers are desorbed. Then the control valve six is opened and the control valve three is closed, and the system normally adsorbs exhaust gas.

2. The simultaneous desorption process of a rotating wheel and a fixed bed according to claim 1, characterized in that: The gas temperature Tmix at the outlet end of the mixing box 2 is detected in real time by the temperature sensor 4, and Tmix is compared with the target desorption temperature T of the activated carbon adsorber. 目标 When Tmix > T 目标 , the system increases the opening degree of the control valve 1. When Tmix < T 目标 , the system decreases the opening degree of the control valve 1.

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