Heating device, unit operation system, and carbon dioxide gas recovery system

Abstract

The present invention aims to provide a heating device that is flexible enough to handle self-heat regeneration even when the compression ratio of the compressor used is low. The present invention also aims to provide a unit operation system and a carbon dioxide gas recovery system equipped with the above heating device. [Solution] A heating device 300 according to one aspect of the present invention is a device for heating water, which is a fluid to be heated, using a reboiler 330 that uses ethanol vapor introduced from a distillation column 100 as a heating fluid, and comprises a preheater 310 into which ethanol vapor from the distillation column 100 is introduced via a first flow path F1, a compressor 320 connected downstream of the preheater 310 via a second flow path F2, a third flow path F3 that supplies at least a portion of the ethanol vapor compressed by the compressor 320 to the preheater 310 as a preheat source, and a reboiler 330 into which the ethanol fluid discharged from the third flow path F3 through the preheater 310 is introduced as a heating fluid.

Description

Technical Field

[0001] The present invention relates to a heating device, a unit operation system, and a carbon dioxide gas recovery system.

Background Art

[0002] Conventionally, techniques for compressing a fluid to raise its temperature are known. For example, the following Patent Document 1 discloses a heating module shown in Figure 15. This heating module has a piping path that supplies the input fluid flowing in from the input end I to the unit operation part b via the heat exchanger a, and then sends the output fluid discharged from the unit operation part b through the heat exchanger a again before delivering it to the output end E. Here, from the time the output fluid exits the unit operation part b until it reaches the output end E, the output fluid is first compressed by the compressor c to raise its temperature, and then supplied to the heat exchanger a. Subsequently, the output fluid after passing through the heat exchanger a is expanded by the expander d to lower its temperature, and is further cooled by the cooling device e. It is described that this heating module not only has a high energy-saving effect, but also can make the pressure of the fluid input to the unit operation part b substantially the same as the pressure of the fluid input to the input end I, so that the unit operation of the unit operation part b can be performed in a substantially constant pressure state.

[0003] Further, the following Patent Document 2 discloses a distillation apparatus shown in Figure 16. This distillation apparatus includes a high-pressure column f, a low-pressure column g, a heat exchange structure h, a compressor i, a first line (lines L1A, L2A, L3A), and a second line (lines L1A and L4A). Here, the outlet vapor flowing through the first line passes through the heat exchange structure h, while the outlet vapor flowing through the second line does not pass through the heat exchange structure h. Therefore, the vapor discharged from the top of the low-pressure column g is compressed by the compressor i to raise its temperature, and is supplied to the bottom of the high-pressure column f via the first line and the second line. In this distillation apparatus, the amount of heat exchange in the heat exchange structure h can be adjusted by adjusting the ratio between the flow rate of the outlet vapor flowing through the first line and the flow rate of the outlet vapor flowing through the second line.

Prior Art Documents

Patent Documents

[0004] [Patent Document 1] Patent No. 5688784 [Patent Document 2] Patent No. 5816476 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] Both of the above-mentioned Patent Documents 1 and 2 employ a heating device that compresses and raises the temperature of the process gas. There are two types of compressors used to compress the process gas: oil-lubricated compressors and oil-free compressors. In the case of oil-lubricated compressors, if they are used for applications such as self-thermal regeneration distillation, concentration, or stripping, there is a risk of oil mist contaminating the process gas. Therefore, especially in self-thermal regeneration equipment and systems that include such equipment (for example, carbon dioxide gas recovery systems), it is considered essential to use oil-free compressors. However, due to their internal structure, oil-free compressors have inferior sealing characteristics compared to oil-lubricated compressors, making it difficult to increase the compression ratio. Because of this limitation on the compression ratio, it is not possible to raise the process gas to the required temperature, which has resulted in a lack of flexibility when applying them to self-thermal regeneration.

[0006] The present invention has been made in view of the above circumstances, and aims to provide a heating device that has the flexibility to handle self-heat regeneration even when the compression ratio of the compressor used is low. The present invention also aims to provide a unit operation system and a carbon dioxide gas recovery system equipped with the above heating device. [Means for solving the problem]

[0007] To solve the above problems and achieve the above objectives, the present invention employs the following configuration. (1) A heating device according to one aspect of the present invention is A device for heating a fluid to be heated using a heater that uses a fluid introduced from a fluid supply source as the heating fluid, A preheater that introduces the fluid from the fluid supply source through a first flow path, A compressor connected to the downstream side of the preheater via a second flow path, A third channel supplies at least a portion of the fluid compressed by the compressor to the preheater as a preheat source, The fluid discharged from the third channel through the preheater is introduced as the heating fluid, and the heater heats the fluid to be heated, It is equipped with.

[0008] According to the heating apparatus described in (1) above, the fluid introduced from the fluid supply source to the preheater via the first channel is preheated and its temperature rises before being introduced to the compressor via the second channel. Subsequently, the fluid introduced to the compressor is further heated by compression by the compressor and then introduced to the preheater through the third channel. In the preheater, the heat of the fluid introduced via the third channel is used as a preheating source to preheat the fluid moving from the first channel through the second channel to the compressor. Therefore, the fluid temperature can be raised in advance before introducing it into the compressor. As a result, the amount of work required by the compressor to compress the fluid to the temperature needed for use as a heating fluid in the heater can be reduced. Thus, the compression ratio required of the compressor can be lowered, relaxing the compression ratio requirements and allowing the use of an oil-free compressor.

[0009] (2) In the heating apparatus described in (1) above, A fourth flow path may be further provided, connecting the first flow path and the second flow path by bypassing the preheater. In the case of the heating device described in (2) above, by diverting at least a portion of the fluid flowing from the first channel through the second channel to the compressor to the fourth channel as needed, the fluid can be supplied to the compressor without preheating by a preheater. Therefore, by adjusting the flow rate of the fluid that flows through the fourth channel and bypasses the preheater as needed, the temperature of the fluid supplied to the compressor can be controlled. In other words, if no bypass is performed, the heat from the fluid heated by the compressor will move from the downstream side of the compressor, through the third channel to the preheater, and then be supplied to the fluid being preheated in the preheater before returning to the compressor, following a circulating path. In contrast, by diverting at least a portion of the fluid heading to the preheater to the fourth channel and bypassing the preheater, the amount of preheat added to the fluid flowing into the compressor can be kept low or adjusted to eliminate preheating altogether. This makes it possible to suppress heat accumulation in the above-mentioned circulating path. The fourth channel may be constructed from a steel pipe made of carbon steel or stainless steel.

[0010] (3) In the case of the heating device described in (2) above, A first acquisition unit that acquires temperature information corresponding to the temperature and pressure information corresponding to the pressure of the fluid flowing through the third channel or the fluid compressed by the compressor, A first flow control unit controls the flow rate of the fluid flowing through the fourth channel according to the temperature information and the pressure information, It may also be provided. In the heating device described in (3) above, if the first flow control unit determines, based on the temperature and pressure information acquired by the first acquisition unit, that the temperature and pressure of the fluid flowing out of the compressor exceed the appropriate range, it increases the flow rate of the fluid flowing through the fourth channel, thereby increasing the flow rate of the fluid bypassing the preheater. This makes it possible to keep the amount of preheating to the fluid entering the compressor low or to adjust it to no preheating at all, thereby suppressing heat accumulation in the circulation path.

[0011] (4) In the case of the heating device described in (2) above, The second flow path includes a confluence channel that combines the fluid led out from the downstream side of the preheater and the fluid flowing through the fourth flow path and introduces them to the upstream side of the compressor. A second acquisition unit acquires temperature information corresponding to the temperature of the fluid flowing through the aforementioned confluence channel, A first flow control unit controls the flow rate of the fluid flowing through the fourth channel according to the temperature information, It may also be provided. In the heating device described in (4) above, the second acquisition unit acquires temperature information of the mixed fluid, which consists of the fluid preheated in the preheater and the fluid that bypasses the preheater and is not preheated. If the second flow control unit determines, based on the acquired temperature information, that the temperature of the mixed fluid exceeds the appropriate range, it increases the flow rate of the fluid bypassing the preheater by increasing the flow rate of the fluid flowing through the fourth channel. This makes it possible to keep the amount of preheating added to the fluid heading to the compressor low, or even adjust it to no preheating at all, thereby suppressing heat accumulation in the circulation path.

[0012] (5) In the case of the heating device described in (2) above, A third acquisition unit acquires temperature information corresponding to the temperature of the fluid flowing through the fourth channel, A first flow control unit controls the flow rate of the fluid flowing through the fourth channel according to the temperature information, It may also be provided. In the heating device described in (5) above, if the first flow control unit determines, based on the temperature information acquired by the third acquisition unit, that the temperature of the fluid supplied from the fluid supply source is lower than the appropriate range for the temperature of the fluid to be sent to the compressor, the flow rate of the fluid flowing through the fourth flow path is reduced. This increases the flow rate of the fluid that is sent to the preheater for preheating, thereby raising the temperature of the fluid flowing into the compressor and adjusting it to the appropriate range.

[0013] (6) In the case of the heating device described in (2) above, The second flow path includes a confluence channel that combines the fluid led out from the downstream side of the preheater and the fluid flowing through the fourth flow path and introduces them to the upstream side of the compressor. a fourth acquisition unit configured to acquire temperature information corresponding to the temperature of the fluid on the downstream side of the preheater and before reaching the merging flow path; a first flow rate control unit configured to control the flow rate of the fluid flowing through the fourth flow path in accordance with the temperature information; may be further provided. In the heating device described in the above (6), the temperature information of the fluid preheated by the preheater is acquired by the fourth acquisition unit. Then, when the first flow rate control unit determines that the temperature of the preheated fluid exceeds an appropriate range based on the acquired temperature information, the flow rate of the fluid that bypasses the preheater through the fourth flow path is increased. Thereby, the amount of preheating applied to the fluid entering the compressor can be kept low, or adjusted to no preheating, and heat storage in the circulation path described above can be suppressed.

[0014] (7) In the heating device described in the above (2), a fifth flow path that connects the downstream side of the compressor and the heater may be further provided. In the case of the heating device described in the above (7), at least a part of the fluid flowing out from the compressor is caused to flow through the fifth flow path as necessary, whereby at least a part of the fluid can be bypassed without passing through the preheater, and heat storage can be suppressed. That is, when the above bypass is not performed, the heat possessed by the fluid whose temperature has been raised by the compressor moves from the downstream side of the compressor, passes through the third flow path, reaches the preheater, follows a circulation path in which the heat is supplied to the fluid to be preheated in the preheater and then returns to the compressor. In contrast, by causing at least a part of the fluid to flow through the fifth flow path to bypass the preheater, the amount of preheating applied to the fluid flowing into the compressor can be kept low, or can be adjusted to no preheating. Thereby, heat storage in the circulation path described above can be suppressed. The fifth flow path may be constituted by a steel pipe made of carbon steel or stainless steel.

[0015] (8) In the heating device described in the above (7), a fifth acquisition unit configured to acquire temperature information corresponding to the temperature of the fluid flowing in the range on the downstream side of the compressor and on the upstream side of the third flow path, and pressure information corresponding to the pressure of the fluid; A second flow control unit controls the flow rate of the fluid flowing from the downstream side of the compressor to the third flow path and the flow rate of the fluid flowing from the downstream side of the compressor to the fifth flow path, in accordance with the temperature information and the pressure information. It may also be provided. In the heating device described in (8) above, if the second flow control unit determines, based on the temperature and pressure information acquired by the fifth acquisition unit, that the temperature and pressure of the fluid flowing out of the compressor exceed the appropriate range, the flow rate of the fluid flowing through the third channel is reduced, and the remaining fluid is flowed through the fifth channel, thereby bypassing the preheater. This makes it possible to keep the amount of preheat added to the fluid entering the compressor low, or even adjust it to no preheating at all, thereby suppressing heat accumulation in the circulation path.

[0016] (9) In the heating apparatus described in (1) above, A fifth flow path may be further provided, connecting the downstream side of the compressor and the heater. In the case of the heating device described in (9) above, by directing at least a portion of the fluid flowing out of the compressor to the fifth channel as needed, at least a portion of the fluid can be bypassed without passing through the preheater, thereby suppressing heat accumulation. That is, if bypassing is not performed, the heat contained in the fluid heated by the compressor will move from the downstream side of the compressor, through the third channel to the preheater, and then be supplied to the fluid being preheated in the preheater before returning to the compressor, following a circulating path. In contrast, by directing at least a portion of the fluid to the fifth channel and bypassing the preheater, the amount of preheat added to the fluid flowing into the compressor can be kept low or adjusted to eliminate preheating altogether. This makes it possible to suppress heat accumulation in the above-mentioned circulating path. The fifth channel may be constructed from a steel pipe made of carbon steel or stainless steel.

[0017] (10) In the heating apparatus described in (9) above, A first acquisition unit acquires temperature information corresponding to the temperature and pressure information corresponding to the pressure of the fluid flowing in a range downstream of the compressor and upstream of the third flow path, A second flow control unit controls the flow rate of the fluid flowing from the downstream side of the compressor to the third flow path and the flow rate of the fluid flowing from the downstream side of the compressor to the fifth flow path, in accordance with the temperature information and the pressure information. It may also be provided. In the heating device described in (10) above, if the second flow control unit determines, based on the temperature and pressure information acquired by the first acquisition unit, that the temperature and pressure of the fluid flowing out of the compressor exceed the appropriate range, the flow rate of the fluid flowing through the third channel is reduced, and the remaining fluid is flowed through the fifth channel to bypass the preheater. This makes it possible to keep the amount of preheating applied to the fluid heading to the compressor low, or to adjust it to no preheating at all, thereby suppressing heat accumulation in the circulation path.

[0018] (11) In the heating apparatus described in (9) above, A second acquisition unit acquires temperature information corresponding to the temperature of the fluid before compression that flows into the compressor, A second flow control unit controls the flow rate of the fluid flowing from the downstream side of the compressor to the third flow path and the flow rate of the fluid flowing from the downstream side of the compressor to the fifth flow path, in accordance with the temperature information. It may also be provided. In the heating device described in (11) above, the second acquisition unit acquires temperature information of a mixed fluid consisting of a fluid preheated in a preheater and a fluid that bypasses the preheater and is not preheated. If the second flow control unit determines, based on the acquired temperature information, that the temperature of the mixed fluid exceeds the appropriate range, it reduces the flow rate of the fluid flowing through the third channel and bypasses the preheater by flowing the remaining fluid through the fifth channel. This makes it possible to keep the amount of preheating added to the fluid heading to the compressor low, or even eliminate preheating altogether, thereby suppressing heat accumulation in the circulation path.

[0019] (12) In the heating device described in any one of the above items (1) to (11), The compressor may be driven by electricity derived from renewable energy. In the case of the heating device described in (12) above, by adopting electricity derived from renewable energy as the power source for the compressor, it is possible to further enhance the effect of reducing environmental impact in addition to the effect of self-heat regeneration.

[0020] (13) A unit operation system according to one aspect of the present invention is A heating device as described in any one of the above items (1) to (11), A unit operation apparatus that uses the heated fluid, heated by the heater, to perform at least one of the following operations on the unit operation fluid: distillation, stripping, concentration, drying, and evaporation. It is equipped with. According to the unit operation system described in (13) above, a heating device equipped with an oil-free compressor can be used, so even when this unit operation system is used for self-heat-regenerating distillation, concentration, stripping, etc., the problem of oil mist mixing with the process gas can be avoided. Distillation is a method of separating the components of a mixture using the difference in boiling points, and is mainly used for the separation and purification of liquid mixtures. Concentration is a process of increasing the concentration of solute by reducing the solvent in a solution. Stripping is a process of removing residual gas in a liquid using steam or the like.

[0021] (14) In the unit operation system described in (13) above, The compressor may be driven by electricity derived from renewable energy. In the case of the unit operation system described in (14) above, by adopting electricity derived from renewable energy as the power source for the compressor, it is possible to further enhance the effect of reducing the environmental burden in addition to the effect of self-heat regeneration.

[0022] (15) A carbon dioxide gas recovery system according to one aspect of the present invention is An absorption tower is provided, which introduces and brings into contact a gas to be separated containing carbon dioxide gas and a lean absorbent, thereby absorbing the carbon dioxide gas in the gas to be separated into the lean absorbent to produce a rich absorbent. A regeneration tower receives the rich absorbent from the absorption tower and regenerates the lean absorbent by heating the rich absorbent and separating the carbon dioxide gas. A heating device for heating the rich absorption liquid that is being drawn out of the regeneration tower and reintroduced into the regeneration tower, Equipped with, The heating device is the heating device described in any one of items (1) to (11) above. The fluid supply source is the regeneration tower, The fluid introduced from the fluid supply source is a mixed gas of carbon dioxide gas and the vapor components of the solute and solvent of the rich absorbent, which is discharged from the regeneration tower. The fluid to be heated is the rich absorbent liquid. According to the carbon dioxide gas recovery system described in (15) above, a heating device equipped with an oil-free compressor can be used, thus avoiding the problem of oil mist mixing with the process gas.

[0023] (16) In the carbon dioxide gas recovery system described in (15) above, The compressor may be driven by electricity derived from renewable energy. In the case of the carbon dioxide gas recovery system described in (16) above, by adopting electricity derived from renewable energy as the power source for the compressor, it is possible to further enhance the effect of reducing environmental impact in addition to the effect of self-heat regeneration. [Effects of the Invention]

[0024] According to each of the above embodiments of the present invention, it is possible to provide a heating device that has the flexibility to handle self-heat regeneration even when the compression ratio of the compressor used is low. Furthermore, according to each of the above embodiments of the present invention, it is possible to provide a unit operation system and a carbon dioxide gas recovery system equipped with the above heating device. [Brief explanation of the drawing]

[0025] [Figure 1]This is a schematic diagram showing a distillation system, which is an example of a unit operation system equipped with a heating device according to one embodiment of the present invention. [Figure 2] This is a schematic diagram showing a first modified example of the same embodiment. [Figure 3] This is a schematic diagram showing a second modified example of the same embodiment. [Figure 4] This is a schematic diagram showing a third modified example of the same embodiment. [Figure 5] This is a schematic diagram showing a fourth modified example of the same embodiment. [Figure 6] This is a schematic diagram showing a fifth modified example of the same embodiment. [Figure 7] This is a schematic diagram showing a sixth modified example of the same embodiment. [Figure 8] This is a schematic diagram showing a carbon dioxide gas recovery system, which is another example of a unit operation system equipped with a heating device according to one embodiment of the present invention. [Figure 9] This figure shows a first modified example of the same embodiment, and is a schematic diagram showing part B of Figure 8. [Figure 10] This figure shows a second modified example of the same embodiment, and is a schematic diagram showing part B of Figure 8. [Figure 11] This figure shows a third modified example of the same embodiment, and is a schematic diagram showing part B of Figure 8. [Figure 12] This figure shows a fourth modified example of the same embodiment, and is a schematic diagram showing part B of Figure 8. [Figure 13] This figure shows a fifth modified example of the same embodiment, and is a schematic diagram showing part B of Figure 8. [Figure 14] This figure shows a sixth modified example of the same embodiment, and is a schematic diagram showing part B of Figure 8. [Figure 15] This is a schematic diagram of a conventional heating module described in Patent Document 1. [Figure 16] This is a schematic diagram of a conventional internal heat exchange distillation column described in Patent Document 2. [Modes for carrying out the invention]

[0026] Embodiments and modifications thereof of the heating device, unit operation system, and carbon dioxide gas recovery system of the present invention will be described below. First, a distillation system shown in Figure 1 will be described as a first embodiment of the unit operation system equipped with the heating device of the present invention. Then, modifications of the distillation system will be described based on Figures 2 to 7. Next, a carbon dioxide gas recovery system shown in Figure 8 will be described as a second embodiment of the unit operation system equipped with the heating device of the present invention. Then, modifications of the carbon dioxide gas recovery system will be described based on Figures 9 to 14.

[0027] [First Embodiment: Distillation System] Generally, distillation systems are systems that separate the components of a mixture using the difference in boiling points, and are mainly used for the separation and purification of liquid mixtures. In this embodiment, an ethanol / water distillation system will be described as an example. In other words, the distillation system of this embodiment takes a distillation raw material liquid consisting of water and ethanol into the distillation column 100, and then separates and recovers liquid ethanol and water by distilling this distillation raw material liquid. Here, an example of the distillation raw material liquid taken into the distillation column 100 is a mixed fluid of 10% ethanol and 90% water. As shown in Figure 1, the distillation system 1000 of this embodiment includes a distillation column 100 and a heating device 300.

[0028] The distillation column 100 is a long, hollow container oriented vertically, and at its top is a vapor outlet for removing ethanol vapor separated by distillation to the outside. At the bottom of the distillation column 100 is a water storage outlet for removing water accumulated there to the outside. On the upper side of the distillation column 100 is a reflux inlet for taking in liquid ethanol for reflux introduced from the reboiler 330 (described later). Furthermore, on the lower side of the distillation column 100 is a heated fluid inlet for taking in heated fluid (a mixture of hot water and steam) introduced from the reboiler 330 into the column. Therefore, the distillation column 100 is connected to the heating device 300 at four locations: its vapor outlet, storage water outlet, flux inlet, and heating fluid inlet.

[0029] The heating device 300 comprises a preheater 310, a compressor 320, a reboiler (heater) 330, a cooler 340, a branching section 350, piping connecting these, control valves and pumps (both not shown) provided in these pipes, and a control device (not shown). The preheater 310 is a heat exchanger that heats the ethanol vapor taken from the top of the distillation column 100 using a preheat source. The vapor outlet of the distillation column 100 and the preheater 310 are connected by piping that forms the first flow path F1. That is, the upstream end of the first flow path F1 is connected to the vapor outlet of the distillation column 100, and the downstream end of the first flow path F1 is connected to the preheater 310.

[0030] The compressor 320 is a device that compresses the ethanol vapor preheated in the preheater 310 to further increase its temperature. Compressors generally come in oil-lubricated and oil-free types, but for reasons described later, an oil-free type is used as the compressor 320 in this heating device 300. It is preferable to use electricity derived from renewable energy sources to drive the compressor 320. In this case, carbon dioxide emissions from the heating device 300 can be reduced.

[0031] The preheater 310 and the suction port of the compressor 320 are connected by a pipe forming a second flow path F2. Specifically, the upstream end of the second flow path F2 is connected to the preheater 310, and the downstream end of the second flow path F2 is connected to the suction port of the compressor 320. The ethanol vapor, compressed and heated by the compressor 320, is supplied to the preheat source intake of the preheater 310 via piping forming the third flow path F3. Specifically, the upstream end of the third flow path F3 is connected to the discharge port of the compressor 320, and the downstream end of the third flow path F3 is connected to the preheat source intake of the preheater 310.

[0032] The first flow path F1 and the second flow path F2 are connected by a piping that forms a fourth flow path F4, which diverts some or all of the ethanol vapor flowing through the first flow path F1 to the second flow path F2, bypassing the preheater 310. Specifically, the upstream end of the fourth flow path F4 is connected to a connection point p1 located midway between one end and the other end of the first flow path F1, and the downstream end of the fourth flow path F4 is connected to a connection point p2 located midway between one end and the other end of the second flow path F2. A T-joint is provided at this connection point p1, connecting the piping that forms the first flow path F1 and the piping that forms the fourth flow path F4. This T-joint allows the ethanol vapor flowing through the first flow path F1 to split into a flow toward the preheater 310 and a flow toward the fourth flow path F4. Here, on the piping that forms the first flow path F1, a flow control valve (not shown) is connected at a position midway between the connection point p1 and the preheater 310. Furthermore, a flow control valve (not shown) is connected to the piping forming the fourth flow path F4. Hereafter, the flow control valve provided in the first flow path F1 and the flow control valve provided in the fourth flow path F4 may be collectively referred to as the first bypass flow control valve.

[0033] The flow control valves in the first flow path F1 and the fourth flow path F4 are each electrically connected to the control device. "Electrically connected" here is not limited to direct connections via wiring, but also includes connections via wireless or internet connections. The flow control valve in the first flow path F1 adjusts the flow rate of ethanol vapor flowing from the first flow path F1 to the preheater 310 upon receiving instructions from the control device. The flow control valve in the fourth flow path F4 adjusts the flow rate of ethanol vapor flowing from the first flow path F1 to the second flow path F2 via the fourth flow path F4, which bypasses the preheater 310. According to the first bypass flow rate control valve, when the total flow rate of ethanol vapor flowing through the first flow path F1 is set to 100%, the proportion of ethanol vapor passing through the preheater 310 can be adjusted between 0% and 100%, and the proportion of ethanol vapor flowing through the fourth flow path F4 can be adjusted to the remainder after subtracting the flow rate of ethanol vapor flowing through the first flow path F1 from the total flow rate (i.e., between 100% and 0%).

[0034] Furthermore, for the fourth channel F4, it is preferable to use a steel pipe made of carbon steel or stainless steel, from the viewpoint of allowing high-temperature and high-pressure fluids to flow without hindrance. Since ethanol vapor (gas) flows through the fourth channel F4, it is even more preferable to use a pipe made of carbon steel.

[0035] The reboiler 330 is a heat exchanger that takes in and heats water stored at the bottom of the distillation column 100. The reboiler 330 uses ethanol fluid (a mixture of ethanol vapor and liquid ethanol) taken in from the preheating fluid outlet of the preheater 310 as its heat source. The preheater 310 and the reboiler 330 are connected by piping that forms the sixth flow path F6. Specifically, the upstream end of the sixth flow path F6 is connected to the preheating fluid outlet of the preheater 310, and the downstream end of the sixth flow path F6 is connected to the heating fluid intake of the reboiler 330.

[0036] A connection point p3 located midway through the sixth flow path F6 and a connection point p4 located midway through the third flow path F3 are connected by piping that forms the fifth flow path F5. Then, some or all of the ethanol vapor flowing out from the compressor 320 can be flowed through the fifth flow path F5 to the sixth flow path F6 and further to the reboiler 330. Specifically, a T-joint is provided at connection point p4, connecting the piping from the discharge port of the compressor 320 to connection point p4 with the piping forming the third flow path F3 and the piping forming the fifth flow path F5. This T-joint allows the ethanol vapor discharged from the compressor 320 to branch into a flow toward the third flow path F3 and a flow toward the sixth flow path F6 via the fifth flow path F5. Here, a flow control valve (not shown) is connected to the piping forming the third flow path F3. Similarly, a flow control valve (not shown) is also connected to the piping forming the fifth flow path F5. Hereafter, the flow control valves provided in the third flow path F3 and the flow control valves provided in the fifth flow path F5 may be collectively referred to as the second bypass flow control valve. The flow control valves in the third flow path F3 and the fifth flow path F5 are each electrically connected to the control device. "Electrically connected" here is not limited to direct connections via wiring, but also includes connections via wireless or internet communication lines. The flow control valve in the third flow path F3 adjusts the flow rate of ethanol vapor from the compressor 320 through the third flow path F3 toward the preheat source intake of the preheater 310 upon receiving instructions from the control device. The flow control valve in the fifth flow path F5 adjusts the flow rate of ethanol vapor bypassed from the compressor 320 through the fifth flow path F5 toward the sixth flow path F6.

[0037] The second bypass flow rate control valve allows the proportion of ethanol vapor flowing to the preheater 310 to be adjusted between 0% and 100% when the total flow rate of ethanol vapor discharged from the compressor 320 is set to 100%, and also allows the proportion of ethanol vapor that bypasses the preheater 310 by passing through the fifth flow path F5 from the compressor 320 to be adjusted to the remainder after subtracting the flow rate of ethanol vapor flowing to the preheater 310 from the total flow rate (i.e., between 100% and 0%). In other words, the second bypass flow rate control valve allows the proportion of ethanol vapor that bypasses the preheater 310 by passing through the fifth flow path F5 to be adjusted between 0% and 100%, and also allows the proportion of ethanol vapor flowing to the preheater 310 from the compressor 320 to be adjusted to the remainder after subtracting the flow rate of ethanol vapor flowing through the fifth flow path F5 from the total flow rate (i.e., between 100% and 0%).

[0038] Furthermore, for the fifth channel F5, it is preferable to use a steel pipe made of carbon steel or stainless steel, from the viewpoint of allowing high-temperature and high-pressure fluids to flow without hindrance. Since ethanol vapor (gas) flows through the fifth channel F5, it is even more preferable to use a pipe made of carbon steel.

[0039] The ethanol fluid supplied to the reboiler 330 as a heat source from the sixth channel F6 heats the water at the bottom of the distillation column 100, and then flows through the piping forming the seventh channel F7 to the cooler 340. The reboiler 330 and the cooler 340 are connected by the seventh channel F7. That is, the upstream end of the seventh channel F7 is connected to the reboiler 330, and the downstream end of the seventh channel F7 is connected to the cooler 340.

[0040] The ethanol fluid flowing from the reboiler 330 to the cooler 340 is cooled in the cooler 340 to become liquid ethanol, which then flows towards the branching section 350. The cooler 340 and the branching section 350 are connected by a pipe forming the eighth flow path F8. Specifically, the upstream end of the eighth flow path F8 is connected to the cooler 340, and the downstream end of the eighth flow path F8 is connected to the liquid ethanol intake of the branching section 350.

[0041] A portion of the liquid ethanol flowing through the eighth channel F8 passes through the branching section 350 and goes to the tenth channel F10, where it is recovered. The remaining portion is separated at the branching section 350 for use as a flux and supplied into the distillation column 100 from the flux intake located on the upper side of the distillation column 100. Both the upstream end of the tenth channel F10 and the upstream end of the ninth channel F9 are connected to the liquid ethanol discharge port of the branching section 350. The flow rate of the flux (liquid ethanol) supplied from the branching section 350 to the distillation column 100 through the ninth channel F9 may be constant, or the control device may automatically adjust it according to the amount of ethanol vapor generated in the distillation column 100.

[0042] As described above, the reboiler 330 is a heat exchanger that takes in and heats the water stored at the bottom of the distillation column 100. The forward path between the reboiler 330 and the bottom of the distillation column 100 consists of an 11th flow path F11, a pump (not shown), a branching section 360, and a 12th flow path F12. Specifically, the upstream end of the 11th flow path F11 is connected to the water outlet at the bottom of the distillation column 100, and the downstream end of the 11th flow path F11 is connected to the water inlet of the branching section 360. Downstream of the branching section 360, the flow branches into two, one of which is connected to the reboiler 330, and the other is connected to a water tank (not shown) via a 13th flow path F13. Furthermore, the return path between the reboiler 330 and the bottom of the distillation column 100 is connected via the 14th flow path F14. That is, the upstream end of the 14th flow path F14 is connected to the reboiler 330, and the downstream end of the 14th flow path F14 is connected to the lower side of the distillation column 100.

[0043] The operation of the distillation system 1000 described above will now be explained. First, in the reboiler 330, water stored at the bottom of the distillation column 100 is introduced into the reboiler 330 via the forward path consisting of the 11th flow path F11, the branch section 360, and the 12th flow path F12. The introduced water flows through a heat exchange tube (not shown) installed inside the reboiler 330. Meanwhile, the ethanol fluid, which has been compressed and heated by the compressor 320, flows outside the heat exchange tube, transferring its heat to the water inside the heat exchange tube through its walls. As a result, the water at the bottom of the column is heated by the ethanol fluid and becomes a heated fluid (a mixture of hot water and steam). After leaving the reboiler 330, this heated fluid is introduced into the distillation column 100 from the lower side via the 14th flow path F14, which is the return path.

[0044] Meanwhile, in the distillation column 100, the raw materials supplied into the column, namely the distillation raw material liquid consisting of water and ethanol, are heated by the heating fluid supplied to the bottom of the column from the reboiler 330. The heated distillation raw material liquid is separated into ethanol vapor and water due to the difference in boiling points between ethanol and water. The relatively lighter ethanol vapor rises through the column, while the relatively heavier water accumulates at the bottom. Ethanol vapor that reaches the top of the distillation column 100 is introduced into the preheater 310 through the first channel F1. The introduced ethanol vapor flows through a heat exchange tube (not shown) provided inside the preheater 310. Meanwhile, ethanol vapor that has been heated by compression in the compressor 320 and supplied from the third channel F3 flows outside the heat exchange tube, transferring heat to the ethanol vapor inside the heat exchange tube through its walls. In this way, the ethanol vapor flowing inside the preheater 310 is preheated using the ethanol vapor heated by compression in the compressor 320 as a preheat source. Therefore, since the ethanol vapor compressed by the compressor 320 is used as a preheat source, no external heating source is required.

[0045] The ethanol vapor preheated in the preheater 310 is supplied to the compressor 320 through the second channel F2. The ethanol vapor is then compressed by the compressor 320, increasing in temperature and pressure, before flowing into the third channel F3. The ethanol vapor flowing through the third channel F3 is supplied to the preheater 310 as a preheat source, heating and increasing the temperature of the ethanol vapor on its way from the first channel F1 to the second channel F2. After preheating in the preheater 310, the ethanol fluid is supplied to the reboiler 330 through the sixth channel F6. In the reboiler 330, as described above, the heat from the ethanol fluid supplied from the sixth channel F6 heats the water at the bottom of the distillation column 100, which is then used as a heating fluid and returned to the bottom of the column. Distillation continues in the distillation column 100 using the heat from this heating fluid. Furthermore, any excess water that flows from the bottom of the tower into the 11th channel F11, other than that supplied to the reboiler 330, is separated at the branching section 360 and discharged into the 13th channel F13.

[0046] Meanwhile, the ethanol fluid supplied to the reboiler 330 from the sixth channel F6, having completed its role as a heat source, is introduced to the cooler 340 via the seventh channel F7, where it is cooled and becomes liquid ethanol. A portion of the liquid ethanol flowing through the eighth channel F8 is recovered through the tenth channel F10, while the remaining portion is separated at the branching section 350 for use as a flux and supplied to the flux intake of the distillation column 100.

[0047] Of the first to fourteenth flow paths F14 described above, the fourth flow path F4 and the fifth flow path F5 are made of carbon steel piping. However, for the other piping as well, if the fluid flowing inside is at high temperature and high pressure, piping made of carbon steel or stainless steel may be used. In this case, it is more preferable to use piping made of carbon steel when the fluid flowing inside is only a gas, while it is more preferable to use piping made of stainless steel when the fluid flowing inside is a liquid or a gas-liquid mixture.

[0048] Incidentally, as mentioned above, compressors generally come in oil-lubricated and oil-free types, and the compressor 320 in this embodiment uses an oil-free type. The reason for this is that, for example, if an oil-lubricated compressor 320 were used, there would be a risk of oil mist mixing with the ethanol vapor passing through the compressor 320. Therefore, a non-oil-lubricated compressor is adopted, but this presents another problem: its sealing characteristics are inferior to those of an oil-lubricated compressor, making it difficult to increase the compression ratio. Consequently, simply adopting a non-oil-lubricated compressor 320 may not be sufficient to raise the ethanol vapor to the required temperature, resulting in insufficient heat supply to the heater 330. And if there is such a lack of heat, the temperature of the heating fluid supplied to the distillation column 100 will naturally not be sufficient, which may hinder the operation of the distillation itself.

[0049] Therefore, in the heating device 300 of this embodiment, ethanol vapor heated by compression in the compressor 320 is supplied to the preheater 310 as a preheat source, and self-heat regeneration is employed to preheat the ethanol vapor passing through the preheater 310 using this preheat source. With this configuration, by pre-heating the temperature of the ethanol vapor before compression, the amount of compression required to raise it to the required temperature at the discharge port of the compressor 320 can be reduced. As a result, the compression ratio required of the compressor 320 is relaxed, and the discharge pressure of the compressor 320 can be reduced. Therefore, it is possible to raise the temperature of the ethanol vapor to the required temperature while lowering the discharge pressure of the compressor 320.

[0050] In addition to this self-heat regeneration, the heating device 300 of this embodiment is also characterized by having the fourth flow path F4 and the fifth flow path F5 described above. To explain this further, firstly, as described above, the heating device 300 of this embodiment employs self-heat regeneration, supplying a portion of the heat contained in the ethanol vapor discharged from the compressor 320 to the ethanol vapor before it is taken into the compressor 320 via the preheater 310. As a result, a heat circulation path is formed in which the heat flows out of the compressor 320, through the third flow path F3, the preheater 310, and then back to the compressor 320 via the second flow path F2. In this circulation path, some heat accumulation may occur during the self-heat regeneration process, but this amount of heat accumulation can be suppressed by using either or both of the fourth flow path F4 and the fifth flow path F5.

[0051] In other words, when using the fourth channel F4, the ethanol vapor flowing through the first channel F1 is bypassed by the preheater 310 and flows to the second channel F2, thereby reducing or eliminating the amount of heat received by the preheater 310. This prevents an excessive increase in the amount of heat stored in the above circulation path. Similarly, when using the fifth flow path F5, the ethanol vapor compressed and heated by the compressor 320 can be bypassed by the preheater 310 and flowed to the sixth flow path F6, thereby reducing or eliminating the flow rate of the preheat source supplied to the preheater 310. This prevents an excessive increase in the amount of heat stored in the above circulation path. Thus, by limiting the amount of heat received when adjusting using the fourth flow path F4, and limiting the amount of heating when adjusting using the fifth flow path F5, it is possible to prevent excessive heat accumulation in the above circulation path. The control of heat received and the control of heating may be performed either individually or simultaneously. In other words, although this embodiment illustrates the case where the fourth channel F4 and the fifth channel F5 are provided together, the configuration is not limited to this. For example, the fifth channel F5 may be omitted and only the heat received by the fourth channel F4 may be adjusted, or the fourth channel F4 may be omitted and only the heating amount by the fifth channel F5 may be adjusted. Alternatively, as shown in Figure 1, the fourth channel F4 and the fifth channel F5 may be provided together, and the heat received by the fourth channel F4 and the heating amount by the fifth channel F5 may be adjusted simultaneously or at appropriate timings.

[0052] In the fourth flow path F4, the flow rate of ethanol vapor flowing from the first flow path F1 to the preheater 310 and the flow rate of ethanol vapor flowing from the first flow path F1 to the fourth flow path F4, bypassing the preheater 310, may be adjusted as appropriate, referring to the state of the fluid (fluid temperature, fluid pressure) flowing at each position in the circulation path. Alternatively, flow path switching control may be performed to direct all (100%) of the ethanol vapor flowing through the first flow path F1 to only one of the fourth flow path F4 and the preheater 310, and not to the other. Similarly, in the fifth flow path F5, the flow rate of ethanol vapor flowing through the third flow path F3 and the flow rate of ethanol vapor bypassing the preheater 310 by flowing through the sixth flow path F6 via the fifth flow path F5 may be adjusted as appropriate, referring to the state of the fluid flowing through each position of the heating device 300 (fluid temperature, fluid pressure). Alternatively, flow path switching control may be performed so that all (100%) of the ethanol vapor compressed by the compressor 320 flows only through one of the fifth flow path F5 and the third flow path F3, and not through the other. The specific details of the control that references the state of the fluid flowing through the above circulation path (fluid temperature, fluid pressure) will be described later as the first to sixth modified examples based on Figures 2 to 7.

[0053] The main points of the heating device 300 described above are summarized below. In other words, the heating device 300 of this embodiment is A device that heats water (fluid to be heated) introduced from the bottom of a distillation column (fluid supply source) 100 using a reboiler (heater) 330 that uses ethanol vapor, which is the fluid introduced from the top of the distillation column 100, as the heating fluid, A preheater 310 introduces ethanol vapor from the top of the distillation column 100 via the first flow path F1, A compressor 320 is connected to the downstream side of the preheater 310 via a second flow path F2, A third flow path F3 supplies at least a portion of the ethanol vapor compressed by the compressor 320 to the preheater 310 as a preheat source, The ethanol fluid, which is discharged from the third channel F3 through the preheater 310, is introduced as the heating fluid into the reboiler 330. It is equipped with.

[0054] According to the heating device 300 described above, ethanol vapor introduced into the preheater 310 from the top of the distillation column 100 via the first channel F1 is preheated and its temperature rises before being introduced into the compressor 320 via the second channel F2. Subsequently, the ethanol vapor introduced into the compressor 320 is further heated by compression by the compressor 320 and then introduced into the preheater 310 via the third channel F3. In the preheater 310, the heat of the ethanol vapor introduced via the third channel F3 is used as a preheating source to preheat the ethanol vapor traveling from the first channel F1 through the second channel F2 to the compressor 320. Therefore, the temperature of the ethanol vapor can be raised in advance before introducing it into the compressor 320. As a result, the amount of work required for the compressor 320 to compress the ethanol vapor to the temperature required for use as a heating fluid in the reboiler 330 can be reduced. Thus, the compression ratio requirements for the compressor 320 are relaxed, and a non-oil-lubricated compressor 320 can be used.

[0055] Furthermore, the heating device 300 of this embodiment is The system further includes a fourth channel F4 that connects the first channel F1 and the second channel F2, bypassing the preheater 310. With this configuration, at least a portion of the ethanol vapor flowing from the first channel F1 through the second channel F2 to the compressor 320 can be passed through the fourth channel F4 as needed, allowing it to flow to the compressor 320 without preheating by the preheater 310. Therefore, by adjusting the flow rate of the ethanol vapor that flows through the fourth channel F4 and bypasses the preheater 310 as needed, the temperature of the ethanol vapor supplied to the compressor 320 can be controlled to an appropriate temperature. In other words, the heat from the ethanol vapor heated by the compressor 320 moves from the downstream side of the compressor 320, passes through the third channel F3 to the preheater 310, and is then supplied to the ethanol vapor preheated in the preheater 310 before returning to the compressor 320. However, by utilizing the fourth channel F4 which bypasses the preheater 310, the amount of preheating can be kept low or even eliminated. This suppresses heat accumulation before and after the compressor 320.

[0056] Furthermore, the heating device 300 of this embodiment is The system further includes a fifth flow path F5 that connects the downstream side of the compressor 320 and the reboiler 330 via a sixth flow path F6. With this configuration, at least a portion of the ethanol vapor flowing out of the compressor 320 can be diverted to the fifth channel F5 as needed, thereby bypassing the preheater 310 and suppressing heat accumulation. In other words, if the above bypass is not performed, the heat from the ethanol vapor heated by the compressor 320 will move from the downstream side of the compressor 320, pass through the third channel F3 to the preheater 310, and then be supplied to the ethanol vapor being preheated in the preheater 310 before returning to the compressor 320, following a circulating path. In contrast, by diverting at least a portion of the ethanol vapor to the fifth channel F5 and bypassing the preheater 310, the amount of preheat added to the ethanol vapor flowing into the compressor 320 can be kept low or adjusted to eliminate preheating altogether. This suppresses heat accumulation in the above circulating path.

[0057] Furthermore, the distillation system 1000 of this embodiment is The above heating device 300, A distillation column (unit operating device) 100 performs distillation on a raw material (unit operating fluid) using a heated fluid (a gas-liquid mixture of water and steam) heated by a reboiler 330, It is equipped with. With this configuration, the distillation operation can be performed in the reboiler 330 without using a heat source such as steam.

[0058] Furthermore, in the distillation system 1000 of this embodiment, The compressor 320 may be driven by electricity derived from renewable energy. In this case, by using electricity derived from renewable energy as the power source for the compressor 320, it becomes possible to further enhance the effect of reducing environmental impact in addition to the effect of self-heat regeneration.

[0059] <First variation> In the distillation system 1000, the heating device 400 shown in Figure 2 may be used instead of the heating device 300 shown in Figure 1. In this modified example, the amount of preheating in the preheater 310 is controlled based on the temperature and pressure information of the ethanol vapor discharged from the compressor 320. The heating device 400 of this modified example includes a first acquisition unit S1 at the discharge port of the compressor 320 or in a piping connected thereto, which acquires temperature information corresponding to the temperature of the ethanol vapor immediately after it has been compressed by the compressor 320, and pressure information corresponding to the pressure. An example of this first acquisition unit S1 is a combination of a thermometer such as a thermocouple and a pressure gauge equipped with a piezoelectric element.

[0060] Furthermore, the heating device 400 of this modified example includes a first flow control unit C1 instead of the first bypass amount control valve located downstream of the connection point p1. This first flow control unit C1 controls the flow rate of ethanol vapor flowing through the fourth flow path F4 according to the temperature information and pressure information obtained by the first acquisition unit S1. As shown by the dashed line in Figure 2, the first flow control unit C1 has a communication function that can acquire temperature information and pressure information from the first acquisition unit S1 by wired or wireless communication, and a control function that adjusts its own valve opening based on the acquired temperature information and pressure information. With this configuration, the temperature information and pressure information acquired by the first acquisition unit S1 is transmitted directly to the first flow control unit C1. The first flow control unit C1 then adjusts itself to the required valve opening based on the acquired temperature information and pressure information. This controls the flow rate of ethanol vapor flowing from the first flow path F1 that is directed towards the preheater 310 and the flow rate that is directed towards the fourth flow path F4 and bypasses the preheater 310.

[0061] Alternatively, the control device may be connected to the first acquisition unit S1 and the first flow control unit C1 via a communication line such as a wired or wireless connection. In this case, the temperature and pressure information acquired by the first acquisition unit S1 is first transmitted to the control device. The control device then transmits the required valve opening to the first flow control unit C1 based on the acquired temperature and pressure information. The first flow control unit C1 then adjusts itself to the valve opening corresponding to the received valve opening. This controls the flow rate of ethanol vapor flowing from the first flow path F1 that is directed towards the preheater 310 and the flow rate that is directed towards the fourth flow path F4 and bypasses the preheater 310. Therefore, with this modified configuration, it is possible to reliably prevent an excessive increase in the amount of heat stored in the heat circulation path described above, which goes from the compressor 320, through the third flow path F3, the preheater 310, and the second flow path F2, and then back to the compressor 320.

[0062] <Second variation> In the distillation system 1000, the heating device 500 shown in Figure 3 may be used instead of the heating device 300 shown in Figure 1. In this modified example, the amount of preheating in the preheater 310 is controlled based on the temperature information of the ethanol vapor before the intake port of the compressor 320. In this modified heating device 500, a second acquisition unit S2 is provided in the piping forming a combined flow path F2a, which is the connection point p2 where the second flow path F2 merges with the fourth flow path F4, and the suction port of the compressor 320. This unit acquires temperature information corresponding to the temperature of the ethanol vapor immediately before it is compressed by the compressor 320. An example of this second acquisition unit S2 is a thermometer such as a thermocouple.

[0063] Furthermore, the heating device 500 of this modified example includes a first flow rate control unit C1 instead of the first bypass amount control valve located downstream of the connection point p1. This first flow rate control unit C1 controls the flow rate of ethanol vapor flowing through the fourth flow path F4 according to the temperature information obtained by the second acquisition unit S2. As shown by the dashed line in Figure 3, the first flow rate control unit C1 has a communication function that can acquire temperature information from the second acquisition unit S2 by wired or wireless communication, and a control function that adjusts its own valve opening based on the acquired temperature information. With this configuration, the temperature information acquired by the second acquisition unit S2 is transmitted directly to the first flow rate control unit C1. The first flow rate control unit C1 then adjusts itself to the required valve opening based on the acquired temperature information. This controls the flow rate of ethanol vapor flowing from the first flow path F1 that is directed towards the preheater 310 and the flow rate that is directed towards the fourth flow path F4 and bypasses the preheater 310.

[0064] Alternatively, the control device may be connected to the second acquisition unit S2 and the first flow control unit C1 via a communication line such as a wired or wireless connection. In this case, the temperature information acquired by the second acquisition unit S2 is first transmitted to the control device. The control device then transmits the required valve opening to the first flow control unit C1 based on the acquired temperature information. The first flow control unit C1 then adjusts the valve to an opening corresponding to the received valve opening. This controls the flow rate of ethanol vapor flowing from the first flow path F1 that is directed towards the preheater 310 and the flow rate that is directed towards the fourth flow path F4 and bypasses the preheater 310. Therefore, with this modified configuration, it is possible to reliably prevent an excessive increase in the amount of heat stored in the heat circulation path described above, which exits from the compressor 320, passes through the third flow path F3, the preheater 310, and the second flow path F2, and then returns to the compressor 320.

[0065] <Third variation> In the distillation system 1000, the heating device 600 shown in Figure 4 may be used instead of the heating device 300 shown in Figure 1. In this modified example, the amount of preheating in the preheater 310 is controlled based on the temperature information of the ethanol vapor in the fourth flow path F4. The heating device 600 of this modified example includes a third acquisition unit S3 in the piping forming the fourth flow path F4, which acquires temperature information corresponding to the temperature of the ethanol vapor flowing through the fourth flow path F4. An example of this third acquisition unit S3 is a thermometer such as a thermocouple.

[0066] Furthermore, the heating device 600 of this modified example includes a first flow rate control unit C1 instead of the first bypass amount control valve provided at the connection point p1. This first flow rate control unit C1 controls the flow rate of ethanol vapor flowing through the fourth flow path F4 according to the temperature information obtained by the third acquisition unit S3. As shown by the dashed line in Figure 4, the first flow rate control unit C1 has a communication function that can acquire temperature information from the third acquisition unit S3 by wired or wireless communication, and a control function that adjusts its own valve opening based on the acquired temperature information. With this configuration, the temperature information acquired by the third acquisition unit S3 is transmitted directly to the first flow rate control unit C1. The first flow rate control unit C1 then adjusts itself to the required valve opening based on the acquired temperature information. This controls the flow rate of ethanol vapor flowing from the first flow path F1 that is directed towards the preheater 310 and the flow rate that is directed towards the fourth flow path F4 and bypasses the preheater 310.

[0067] Alternatively, the control device may be connected to the third acquisition unit S3 and the first flow control unit C1 via a communication line such as a wired or wireless connection. In this case, the temperature information acquired by the third acquisition unit S3 is first transmitted to the control device. The control device then transmits the required valve opening to the first flow control unit C1 based on the acquired temperature information. The first flow control unit C1 then adjusts itself to the valve opening corresponding to the received valve opening. This controls the flow rate of ethanol vapor flowing from the first flow path F1 that is directed towards the preheater 310 and the flow rate that is directed towards the fourth flow path F4 and bypasses the preheater 310. Therefore, according to the configuration of this modified example, it is possible to reliably prevent an excessive increase in the amount of heat stored in the heat circulation path described above, which exits from the compressor 320, passes through the third flow path F3, the preheater 310, and the second flow path F2, and returns to the compressor 320.

[0068] <Fourth variation> In the distillation system 1000, the heating device 700 shown in Figure 5 may be used instead of the heating device 300 shown in Figure 1. In this modified example, the amount of preheating in the preheater 310 is controlled based on the temperature information of the ethanol vapor in the range from when it leaves the preheater 310 until it reaches the inlet of the confluence channel F2a. The heating device 700 of this modified example includes a fourth acquisition unit S4 between the preheater 310 and the connection point p2, which is the junction point of the fourth flow path F4 on the second flow path F2, for acquiring temperature information corresponding to the temperature of the ethanol vapor passing through this position. An example of this fourth acquisition unit S4 is a thermometer such as a thermocouple.

[0069] Furthermore, the heating device 700 of this modified example includes a first flow control unit C1 instead of the first bypass amount control valve provided at connection point p1. This first flow control unit C1 controls the flow rate of ethanol vapor flowing through the fourth flow path F4 according to the temperature information obtained by the fourth acquisition unit S4. As shown by the dashed line in Figure 5, this first flow control unit C1 has a communication function that can acquire temperature information from the fourth acquisition unit S4 by wired or wireless communication, and a control function that adjusts its own valve opening based on the acquired temperature information. With this configuration, the temperature information acquired by the fourth acquisition unit S4 is transmitted directly to the first flow control unit C1. The first flow control unit C1 then adjusts itself to the required valve opening based on the acquired temperature information. This controls the flow rate of ethanol vapor flowing from the first flow path F1 that is directed towards the preheater 310 and the flow rate that is directed towards the fourth flow path F4 and bypasses the preheater 310.

[0070] Alternatively, the control device may be connected to the fourth acquisition unit S4 and the first flow control unit C1 via a wired or wireless communication line. In this case, the temperature information acquired by the fourth acquisition unit S4 is first transmitted to the control device. The control device then transmits the required valve opening to the first flow control unit C1 based on the acquired temperature information. The first flow control unit C1 then adjusts itself to the valve opening corresponding to the received valve opening. This controls the flow rate of ethanol vapor flowing from the first flow path F1 that is directed towards the preheater 310 and the flow rate that is directed towards the fourth flow path F4 and bypasses the preheater 310. Therefore, according to the configuration of this modified example, it is possible to reliably prevent an excessive increase in the amount of heat stored in the heat circulation path described above, which exits from the compressor 320, passes through the third flow path F3, the preheater 310, and the second flow path F2, and returns to the compressor 320.

[0071] <Fifth variation> In the distillation system 1000, the heating device 800 shown in Figure 6 may be used instead of the heating device 300 shown in Figure 1. In this modified example, the amount of preheating in the preheater 310 is controlled based on the temperature and pressure information of the ethanol vapor flowing through the third flow path F3. The heating device 800 in this modified example is equipped with a fifth data acquisition unit S5 in the piping forming the third flow path F3, which acquires temperature information corresponding to the temperature of the ethanol vapor before it reaches the preheater 310 and pressure information corresponding to the pressure. An example of this fifth data acquisition unit S5 is a combination of a thermometer such as a thermocouple and a pressure gauge equipped with a piezoelectric element.

[0072] Furthermore, the heating device 800 of this modified example includes a first flow control unit C1 instead of the first bypass amount control valve provided at connection point p1. This first flow control unit C1 controls the flow rate of ethanol vapor flowing through the fourth flow path F4 according to the temperature information and pressure information obtained by the fifth acquisition unit S5. As shown by the dashed line in Figure 6, this first flow control unit C1 has a communication function that can acquire temperature information and pressure information from the fifth acquisition unit S5 by wired or wireless communication, and a control function that adjusts the valve opening itself based on the acquired temperature information and pressure information. With this configuration, the temperature information and pressure information acquired by the fifth acquisition unit S5 is directly transmitted to the first flow control unit C1. The first flow control unit C1 then adjusts itself to the required valve opening based on the acquired temperature information and pressure information. This controls the flow rate of ethanol vapor flowing from the first flow path F1 that is directed towards the preheater 310 and the flow rate that is directed towards the fourth flow path F4 and bypasses the preheater 310.

[0073] Alternatively, the control device may be connected to the fifth data acquisition unit S5 and the first flow control unit C1 via a wired or wireless communication line. In this case, the temperature and pressure information acquired by the fifth data acquisition unit S5 is first transmitted to the control device. The control device then transmits the required valve opening to the first flow control unit C1 based on the acquired temperature and pressure information. The first flow control unit C1 then adjusts itself to the valve opening corresponding to the received valve opening. This controls the flow rate of ethanol vapor flowing from the first flow path F1 that is directed towards the preheater 310 and the flow rate that is directed towards the fourth flow path F4 and bypasses the preheater 310. Therefore, according to the configuration of this modified example, it is possible to reliably prevent an excessive increase in the amount of heat stored in the heat circulation path described above, which exits from the compressor 320, passes through the third flow path F3, the preheater 310, and the second flow path F2, and returns to the compressor 320.

[0074] <Sixth variation> In the distillation system 1000, the heating device 900 shown in Figure 7 may be used instead of the heating device 300 shown in Figure 1. In this modified example, the amount of preheat supplied to the preheater 310 as a preheat source from the ethanol vapor discharged from the compressor 320 is controlled based on the temperature and pressure information of the ethanol vapor discharged from the compressor 320. The heating device 900 of this modified example includes a sixth data acquisition unit S6 at the discharge port of the compressor 320 or in a piping connected thereto, which acquires temperature information corresponding to the temperature of the ethanol vapor immediately after it has been compressed by the compressor 320, and pressure information corresponding to the pressure. An example of this sixth data acquisition unit S6 is a combination of a thermometer such as a thermocouple and a pressure gauge equipped with a piezoelectric element.

[0075] Furthermore, the heating device 900 of this modified example includes a second flow control unit C2 that controls the flow rate of ethanol vapor discharged from the compressor 320 to the third flow path F3 and the flow rate of ethanol vapor discharged from the compressor 320 to the fifth flow path F5, according to the temperature and pressure information obtained in the sixth acquisition unit S6. The second flow control unit C2 includes a first valve C21 connected to the piping forming the third flow path F3 and a second valve C22 connected to the piping forming the fifth flow path F5. By appropriately synchronously controlling the opening degrees of these two valves, the flow rate of ethanol vapor discharged from the compressor 320 to the third flow path F3 and the flow rate of ethanol vapor discharged from the compressor 320 to the fifth flow path F5 can be controlled.

[0076] The second flow control unit C2 has a communication function that can acquire temperature and pressure information from the sixth acquisition unit S6 via wired or wireless communication, and a control function that adjusts the valve opening of the first valve C21 and the second valve C22 based on the acquired temperature and pressure information. With this configuration, the temperature and pressure information acquired by the sixth acquisition unit S6 is directly transmitted to the second flow control unit C2. The second flow control unit C2 then adjusts the valve opening of the first valve C21 and the second valve C22 based on the acquired temperature and pressure information. This controls the flow rate of ethanol vapor discharged from the outlet of the compressor 320 that flows into the third flow path F3 as a preheating source, and the flow rate that flows from the fifth flow path F5 through the sixth flow path F6 to the reboiler 330.

[0077] Alternatively, the control device may be connected to the sixth data acquisition unit S6 and the second flow control unit C2 via a wired or wireless communication line. In this case, the sixth data acquisition unit S6 first transmits the acquired temperature and pressure information to the control device. The control device then transmits the valve openings of the first valve C21 and the second valve C22 to the second flow control unit C2 based on the acquired temperature and pressure information. The second flow control unit C2 then adjusts the valve openings of the first valve C21 and the second valve C22 based on the acquired temperature and pressure information. This controls the flow rate of ethanol vapor discharged from the compressor 320 to the third flow path F3 as a preheating source, and the flow rate that is directed from the fifth flow path F5 to the sixth flow path F6 and then to the reboiler 330 without going to the preheater 310. Therefore, according to the configuration of this modified example, it is possible to more reliably prevent an excessive increase in the amount of heat stored in the heat circulation path described above, which exits from the compressor 320, passes through the third flow path F3, the preheater 310, and the second flow path F2, and then returns to the compressor 320. In this modified example, the flow rates of ethanol vapor flowing through the third channel F3 and the fifth channel F5 are controlled based on the temperature and pressure information of the ethanol vapor at the location where it is discharged from the compressor 320. Alternatively, the location where the temperature and pressure information of the ethanol vapor is acquired may be the third channel F3. Or, instead of the ethanol vapor discharged from the compressor 320, the flow rates of ethanol vapor flowing through the third channel F3 and the fifth channel F5 may be adjusted based on the temperature information of the ethanol vapor flowing through one of the second channel F2, the combined channel F2a, or the fourth channel F4.

[0078] In the first embodiment and the first to sixth modifications described above, the unit operating system is a distillation system 1000, the fluid supply source and unit operating device are a distillation column 100, the fluid introduced from the fluid supply source is ethanol vapor, and the fluid to be heated by the heater (heating device 300) is water. However, the present invention is not limited to this embodiment. In the example above, the heating device 300 was used as a heat source when performing distillation in the distillation column 100. However, instead of distillation, at least one of the following processes—stripping, concentration, drying, and evaporation—may be performed on the unit working fluid, and the heating device 300 may be used as a heat source in that process. In other words, the fluid introduced from the fluid supply source may be a fluid other than ethanol vapor. Also, the fluid to be heated by the heater (heating device 300) may be a fluid other than water.

[0079] [Second Embodiment: Carbon Dioxide Gas Recovery System] As a second embodiment of the unit operation system equipped with the heating device of the present invention, a carbon dioxide gas recovery system 2000 shown in Figure 8 will be described. Subsequently, modified examples of the carbon dioxide gas recovery system 2000 will be described based on Figures 9 to 14. Furthermore, the carbon dioxide gas recovery system 2000 of this embodiment employs a heating device that has the same configuration as the heating device 300 described in the first embodiment, as a heating device for heating the rich absorbent liquid that is taken out from the regeneration tower 3 and then reintroduced into the regeneration tower 3. Therefore, in the description of this embodiment, equipment having substantially the same function / role as in the first embodiment will be described using the same part numbers as the equipment used in the first embodiment. On the other hand, equipment having a different function / role than in the first embodiment will be described using different reference numerals.

[0080] As shown in Figure 8, the carbon dioxide gas recovery system 2000 of this embodiment comprises a carbon dioxide gas recovery device 200 and a heating device 300. The carbon dioxide gas recovery device 200 will be described first, followed by the heating device 300.

[0081] (1) Carbon dioxide gas recovery device 200 The carbon dioxide gas recovery apparatus 200 of this embodiment recovers carbon dioxide gas from a carbon dioxide-containing gas by absorption and separation using a CO2 chemical absorption separation method, and also produces decarbonated gas obtained by separating carbon dioxide gas from the carbon dioxide-containing gas. In this CO2 chemical absorption separation method, an absorbent liquid capable of absorbing carbon dioxide gas is used. As this absorbent liquid, for example, an amine absorbent liquid can be used, which employs monoethanolamine (MEA) or diethanolamine (DEA) as the solute and water as the solvent.

[0082] As shown in Figure 8, the carbon dioxide gas recovery device 200 comprises an absorption tower 2, a regeneration tower 3, a rich absorbent supply passage 4, and a lean absorbent supply passage 5. Absorption tower 2 brings a carbon dioxide-containing gas into contact with a lean absorbent capable of absorbing carbon dioxide gas, allowing the carbon dioxide gas in the gas to be absorbed by the lean absorbent to produce a rich absorbent. Meanwhile, regeneration tower 3 regenerates the rich absorbent supplied from absorption tower 2 into a lean absorbent by heating it and separating the carbon dioxide gas from the rich absorbent. Rich absorbent supply channel 4 supplies the rich absorbent from absorption tower 2 to regeneration tower 3. Lean absorbent supply channel 5 supplies the lean absorbent from regeneration tower 3 to absorption tower 2.

[0083] An introduction channel 2d for introducing carbon dioxide-containing gas into the absorption tower 2 is provided at the bottom 2a of the absorption tower 2. A first nozzle 7 for supplying lean absorbent liquid downwards into the tower is installed at the top 2b of the absorption tower 2. An absorption tower packing material 8 is contained in the intermediate section 2c of the absorption tower 2, located between the top 2b and the bottom 2a of the absorption tower 2, which brings the lean absorbent liquid and carbon dioxide-containing gas into contact with each other at its surface. Furthermore, the absorption tower 2 is provided with an outlet passage 9 for dischargeing decarbonated gas from the top 2b of the absorption tower 2 to the outside of the tower, and a decarbonated gas washing system 10 for dischargeing washing water (washing liquid) stored in the top 2b of the absorption tower 2 from the absorption tower 2, cooling it, and then reintroducing it into the top 2b of the absorption tower 2.

[0084] The decarbonation gas cleaning system 10 includes a liquid receiving tray 11 positioned above the first nozzle 7 for storing cleaning water, a second nozzle 12 positioned above the liquid receiving tray 11 for supplying cleaning water downward, and piping 13 connecting the liquid receiving tray 11 and the second nozzle 12. The piping 13 is equipped with a cleaning water circulation pump 13a that transfers cleaning water from the liquid receiving tray 11 to the second nozzle 12 through the piping 13, and a water-cooled cleaning water cooler 15 that cools the cleaning water downstream of the cleaning water circulation pump 13a. Furthermore, it is preferable that the washing water is the same as the solute of the absorbent solution (for example, water). Here, the absorbent solution refers to a lean absorbent solution, a rich absorbent solution, or a mixture of a lean absorbent solution and a rich absorbent solution.

[0085] The rich absorbent liquid supply passage 4 connects the bottom 2a of the absorption tower 2 to the third nozzle 16, which is located in the top 3b of the regeneration tower 3 and supplies the rich absorbent liquid downwards. The rich absorbent liquid supply passage 4 is equipped with an absorption tower bottom pump 17 that transfers the rich absorbent liquid from the bottom 2a of the absorption tower 2 to the third nozzle 16 through the rich absorbent liquid supply passage 4.

[0086] The regeneration column packing material 18 is contained within the intermediate section 3c of the regeneration column 3, located between the top section 3b and the bottom section 3a. The absorbent liquid flowing down the surface of this regeneration column packing material 18 comes into gas-liquid contact with the vapors of the solute and solvent (e.g., water) of the absorbent liquid rising inside the regeneration column 3, as well as a gas mixture of these vapors and carbon dioxide gas.

[0087] The lean absorbent liquid supply channel 5 connects the bottom 3a of the regeneration tower 3 to the first nozzle 7 inside the absorption tower 2. The lean absorbent liquid supply channel 5 is equipped with a regeneration tower bottom pump 35 that transfers lean absorbent liquid from the bottom 3a of the regeneration tower 3 to the first nozzle 7 via the lean absorbent liquid supply channel 5. Furthermore, an amine heat exchanger 36 is interposed between the lean absorbent supply channel 5 and the rich absorbent supply channel 4 to exchange heat between the lean absorbent and the rich absorbent.

[0088] (2) Heating device 300 The heating device 300 comprises a preheater 310, a compressor 320, a reboiler (heater) 330, a cooler 340, a gas-liquid separator 350A, piping connecting these, control valves and pumps (not shown) provided in these pipes, and a control device (not shown). The preheater 310 is a heat exchanger that heats the mixed gas (a mixture of carbon dioxide gas and the vapor components of the solute and solvent of the absorbent) taken out from the top 3b of the regeneration tower 3 using a preheat source. The regeneration tower 3 and the preheater 310 are connected by piping that forms the first flow path F1. Specifically, the upstream end of the first flow path F1 is connected to the top 3b of the regeneration tower 3, and the downstream end of the first flow path F1 is connected to the preheater 310.

[0089] The compressor 320 is a device that compresses the mixed gas preheated in the preheater 310 to further increase its temperature. Generally, compressors come in oil-lubricated and oil-free types, but for reasons described later, the compressor 320 in this heating device 300 is of the oil-free type. It is preferable to use electricity derived from renewable energy sources to drive the compressor 320. In this case, carbon dioxide emissions from the heating device 300 can be reduced.

[0090] The preheater 310 and the suction port of the compressor 320 are connected by a pipe forming a second flow path F2. Specifically, the upstream end of the second flow path F2 is connected to the preheater 310, and the downstream end of the second flow path F2 is connected to the suction port of the compressor 320. The mixed gas, compressed and heated by the compressor 320, is supplied to the preheater 310 via piping forming the third flow path F3. Specifically, the upstream end of the third flow path F3 is connected to the discharge port of the compressor 320, and the downstream end of the third flow path F3 is connected to the preheater 310.

[0091] The first flow path F1 and the second flow path F2 are connected by a piping that forms a fourth flow path F4, which diverts some or all of the mixed gas flowing through the first flow path F1 to the second flow path F2, bypassing the preheater 310. Specifically, the upstream end of the fourth flow path F4 is connected to a connection point p1 located midway between one end and the other end of the first flow path F1, and the downstream end of the fourth flow path F4 is connected to a connection point p2 located midway between one end and the other end of the second flow path F2. A T-joint is provided at this connection point p1, connecting the piping that forms the first flow path F1 and the piping that forms the fourth flow path F4. This T-joint allows the mixed gas flowing through the first flow path F1 to split into a flow toward the preheater 310 and a flow toward the fourth flow path F4. Here, on the piping that forms the first flow path F1, a flow control valve (not shown) is connected at a position midway between the connection point p1 and the preheater 310. Furthermore, a flow control valve (not shown) is connected to the piping forming the fourth flow path F4. Hereafter, the flow control valve provided in the first flow path F1 and the flow control valve provided in the fourth flow path F4 may be collectively referred to as the first bypass flow control valve.

[0092] The flow control valves in the first flow path F1 and the fourth flow path F4 are each electrically connected to the control device. "Electrically connected" here includes not only direct connections via wiring, but also connections via wireless or internet connections. The flow control valve in the first flow path F1 adjusts the flow rate of the mixed gas flowing from the first flow path F1 to the preheater 310 upon receiving instructions from the control device. The flow control valve in the fourth flow path F4 adjusts the flow rate of the mixed gas flowing from the first flow path F1 through the fourth flow path F4, which bypasses the preheater 310, to the second flow path F2. According to the first bypass flow rate control valve, when the total flow rate of the mixed gas flowing through the first flow path F1 is set to 100%, the proportion of the mixed gas passing through the preheater 310 can be adjusted between 0% and 100%, and the proportion of the mixed gas flowing through the fourth flow path F4 can be adjusted to the remainder after subtracting the flow rate of the mixed gas flowing through the first flow path F1 from the total flow rate (i.e., between 100% and 0%).

[0093] Furthermore, for the fourth channel F4, it is preferable to use a steel pipe made of carbon steel or stainless steel from the viewpoint of allowing high-temperature fluids to flow without hindrance. Since a mixed gas (gas-liquid mixture) flows through the fourth channel F4, it is even more preferable to use piping made of stainless steel.

[0094] The reboiler 330 is a heat exchanger that takes in the rich absorbent liquid stored in the liquid receiving tray 21 of the regeneration tower 3 and heats it. The reboiler 330 uses the heated mixed gas (heated mixed gas by the compressor 320) taken in from the preheater 310 as its heat source. The preheater 310 and the reboiler 330 are connected by piping that forms the sixth flow path F6. That is, the upstream end of the sixth flow path F6 is connected to the preheater 310, and the downstream end of the sixth flow path F6 is connected to the reboiler 330.

[0095] A connection point p3 located midway through the sixth flow path F6 and a connection point p4 located midway through the third flow path F3 are connected by piping that forms the fifth flow path F5. Then, some or all of the heated mixed gas flowing through the third flow path F3 can be flowed through the fifth flow path F5 to the sixth flow path F6 and further to the reboiler 330. Specifically, a T-joint is provided at connection point p4, connecting the piping from the discharge port of the compressor 320 to connection point p4 with the piping forming the third flow path F3 and the piping forming the fifth flow path F5. This T-joint allows the heated mixed gas discharged from the compressor 320 to branch into a flow toward the third flow path F3 and a flow toward the sixth flow path F6 via the fifth flow path F5. Here, a flow control valve (not shown) is connected to the piping forming the third flow path F3. Similarly, a flow control valve (not shown) is also connected to the piping forming the fifth flow path F5. Hereafter, the flow control valves provided in the third flow path F3 and the flow control valves provided in the fifth flow path F5 may be collectively referred to as the second bypass flow control valve. The flow control valves in the third flow path F3 and the fifth flow path F5 are each electrically connected to the control device. "Electrically connected" here is not limited to direct connections via wiring, but also includes connections via wireless or internet communication lines. The flow control valve in the third flow path F3 adjusts the flow rate of the heated mixed gas from the compressor 320 outlet through the third flow path F3 to the preheater 310 upon receiving instructions from the control device. The flow control valve in the fifth flow path F5 adjusts the flow rate of the heated mixed gas bypassed from the compressor 320 outlet through the fifth flow path F5 to the sixth flow path F6.

[0096] The second bypass flow control valve allows the proportion of the heated mixed gas flowing to the preheater 310 to be adjusted between 0% and 100% when the total flow rate of the heated mixed gas discharged from the compressor 320 is 100%, and also allows the proportion of the heated mixed gas that bypasses the preheater 310 by passing through the fifth flow path F5 from the compressor 320 to be adjusted to the remainder (i.e., between 100% and 0%). In other words, the second bypass flow control valve allows the proportion of the heated mixed gas that bypasses the preheater 310 by passing through the fifth flow path F5 to be adjusted between 0% and 100%, and also allows the proportion of the heated mixed gas flowing from the compressor 320 to the preheater 310 to be adjusted to the remainder (i.e., between 100% and 0%).

[0097] Furthermore, for the fifth channel F5, it is preferable to use a steel pipe made of carbon steel or stainless steel from the viewpoint of allowing high-temperature and high-pressure fluids to flow without hindrance. Since the fifth channel F5 carries a heated mixed gas (gas-liquid mixture), it is even more preferable to use a pipe made of stainless steel.

[0098] The heated mixed gas supplied to the reboiler 330 as a heat source from the sixth channel F6 heats the rich absorbent liquid taken from the liquid receiving tray 21 of the regeneration tower 3, and then flows through the piping forming the seventh channel F7 to the cooler 340. The reboiler 330 and the cooler 340 are connected by the seventh channel F7. That is, the upstream end of the seventh channel F7 is connected to the reboiler 330, and the downstream end of the seventh channel F7 is connected to the cooler 340.

[0099] The mixed gas flowing from the reboiler 330 to the cooler 340 is cooled in the cooler 340 before being introduced to the gas-liquid separator 350A, where it is separated into condensate and carbon dioxide gas. The cooler 340 and the gas-liquid separator 350A are connected by piping forming the eighth flow path F8. That is, the upstream end of the eighth flow path F8 is connected to the cooler 340, and the downstream end of the eighth flow path F8 is connected to the gas-liquid separator 350A. The carbon dioxide gas separated in the gas-liquid separator 350A is discharged from the 10th channel F10. Meanwhile, the condensate (condensed solute and solvent vapors) separated in the gas-liquid separator 350A is reintroduced to the regeneration tower 3 through the 9th channel F9 and the 4th nozzle 28.

[0100] As described above, the reboiler 330 is a heat exchanger that takes in the rich absorbent liquid stored in the liquid receiving tray 21 of the regeneration tower 3 and heats it. The forward path between the reboiler 330 and the regeneration tower 3 consists of the 11th flow path F11 and a pump (not shown). That is, the upstream end of the 11th flow path F11 is connected to the regeneration tower 3, and the downstream end of the 11th flow path F11 is connected to the reboiler 330. Furthermore, the return path between the reboiler 330 and the regeneration tower 3 is connected via the 14th channel F14. That is, the upstream end of the 14th channel F14 is connected to the reboiler 330, and the downstream end of the 14th channel F14 is connected to the lower side of the regeneration tower 3.

[0101] The operation of the carbon dioxide gas recovery system 2000, which has the configuration described above, will be explained below. In this explanation, first, the operation mainly of the carbon dioxide gas recovery device 200 will be described, and then the operation mainly of the heating device 300 will be described.

[0102] The flow of the absorbent liquid in the carbon dioxide gas recovery device 200 will be explained starting from the absorption tower 2. First, in the absorption tower 2, the carbon dioxide-containing gas supplied to the bottom 2a rises through the tower, while the lean absorbent liquid supplied from the first nozzle 7 in the top 2b descends through the tower. During this process, the carbon dioxide-containing gas and the lean absorbent liquid come into contact with each other, and the carbon dioxide gas in the carbon dioxide-containing gas is absorbed by the lean absorbent liquid.

[0103] As described above, the absorption tower packing material 8 is placed in the intermediate section 2c of the absorption tower 2. This absorption tower packing material 8 has a fin configuration with numerous narrow gaps, resulting in a large fin surface area per unit volume. Furthermore, the gaps are configured so that the flow path angle changes regularly, intentionally causing flow turbulence. On the surface of the absorption tower packing material 8, the lean absorbent flows down on the fins, forming a wet wall, and comes into gas-liquid contact with the carbon dioxide-containing gas rising inside the absorption tower 2. In addition, the absorption tower packing material 8 is structured in such a way that the narrow gaps in the wet wall and the constant pitch of the changing direction of travel disrupt the gas-liquid flow, thereby making gas-liquid contact more efficient. Therefore, on the surface of the absorption tower packing material 8, the rising carbon dioxide-containing gas and the descending lean absorbent material come into easy contact, promoting the absorption of carbon dioxide gas by the lean absorbent material.

[0104] This generates a rich absorbent and decarbonated gas. Of these, the decarbonated gas rises towards the top 2b of the absorption tower 2 and is discharged to the outside through the outlet 9. Furthermore, in this embodiment, since the absorption tower 2 is equipped with the decarbonation gas cleaning system 10, the top portion 2b of the absorption tower 2 can be cooled by the cleaning water that is cooled by the water-cooled cleaning water cooler 15 and reintroduced. Therefore, for example, even if the solute in the lean absorption liquid is scattered or evaporated and rises along with the decarbonation gas, the solute is supplied to the decarbonation gas cleaning system 10 before reaching the outlet 9. This prevents the solute in the lean absorption liquid from flowing out of the top portion 2b of the absorption tower 2 through the outlet 9 to the outside.

[0105] Meanwhile, the rich absorbent liquid generated along with the decarbonated gas descends through the absorption tower 2 and is stored at the bottom 2a of the tower. From there, it is supplied through the rich absorbent liquid supply passage 4 to the third nozzle 16 at the top 3b of the regeneration tower 3. Here, an amine heat exchanger 36 is interposed between the lean absorbent liquid supply passage 5 and the rich absorbent liquid supply passage 4. The rich absorbent liquid flowing through the lean absorbent liquid supply passage 5 exchanges heat with the lean absorbent liquid flowing through the lean absorbent liquid supply passage 5, thereby cooling the lean absorbent liquid while heating itself.

[0106] Inside the regeneration tower 3, the rich absorbent liquid supplied from the third nozzle 16 descends through the tower, and the rich absorbent liquid, which has been discharged from the liquid receiving tray 21 and heated by the reboiler 330 in a procedure described later, is reintroduced to the bottom of the tower 3a. At this time, a portion of the heated rich absorbent liquid flashes in the vapor generation section 22, and a portion of the solute and solvent in the rich absorbent liquid turns into vapor, and the regenerated carbon dioxide turns into gas, rising inside the regeneration tower 3. In this process, the rich absorbent liquid comes into contact with the vapors of the solute and solvent, and an endothermic reaction of desorption regeneration occurs using the heat of condensation of the vapors of the solute and solvent as a heat source, separating carbon dioxide gas from the rich absorbent liquid.

[0107] As described above, regeneration column packing material 18 is arranged in the intermediate section 3c of the regeneration column 3. This regeneration column packing material 18 has a fin configuration with numerous narrow gaps, resulting in a large fin surface area per unit volume. Furthermore, the gaps are configured to change the flow path angle regularly, intentionally creating flow turbulence. On the surface of the regeneration column packing material 18, the rich absorption liquid flows down on the fins, forming a wet wall, and comes into contact with the vapors of the solute and solvent rising inside the regeneration column 3. Due to the large surface area and flow turbulence, efficient gas-liquid contact occurs, promoting the separation and release of carbon dioxide.

[0108] This separates the rich absorbent into a lean absorbent and carbon dioxide gas. Of these, the carbon dioxide gas mixes with the vapors of the solute and solvent to form a mixed gas. This mixed gas rises through the regeneration tower 3 and flows into the first flow path F1 of the heating device 300.

[0109] Next, we will explain the operation mainly involving the heating device 300. First, in the reboiler 330, the rich absorbent liquid stored in the liquid receiving tray 21 of the regeneration tower 3 is introduced into the reboiler 330 via the 11th flow path F11, which is the forward path. The introduced rich absorbent liquid flows through a heat exchange tube (not shown) provided inside the reboiler 330. Meanwhile, the heated mixed gas, which has been compressed and heated by the compressor 320, flows on the outside of the heat exchange tube, transferring its heat through the wall of the heat exchange tube to the rich absorbent liquid inside the tube. As a result, the rich absorbent liquid is heated by the heated mixed gas and becomes a heated fluid. After leaving the reboiler 330, this heated fluid is introduced into the regeneration tower 3 from the lower side of the regeneration tower 3 via the 14th flow path F14, which is the return path.

[0110] Meanwhile, at the top 3b of the regeneration tower 3, the mixed gas is introduced into the preheater 310 through the first flow path F1. The introduced mixed gas flows through a heat exchange tube (not shown) provided inside the preheater 310. During this time, the heated mixed gas, which has been heated by compression in the compressor 320 and supplied from the third flow path F3, flows outside the heat exchange tube, transferring its heat to the mixed gas inside the heat exchange tube through the wall surface of the tube. In this way, the heated mixed gas, which has been heated by compression in the compressor 320, is used as a preheat source to preheat the mixed gas flowing inside the preheater 310. Thus, in the heating device 300 of this embodiment, the heated mixed gas compressed by the compressor 320 is used as a preheat source, so no external heat source is required.

[0111] The mixed gas, preheated in the preheater 310, is supplied to the compressor 320 through the second flow path F2. The mixed gas is then compressed by the compressor 320, increasing in temperature and pressure to become a heated mixed gas. After reaching connection point p4, the heated mixed gas is directed to the third flow path F3 by adjusting the flow path control valve. If necessary, part or all of it is bypassed to the sixth flow path F6 via the fifth flow path F5 by adjusting the flow path control valve. This bypass will be described later. First, when the heated mixed gas is supplied to the third channel F3, it is supplied to the preheater 310 as a preheat source, heating the mixed gas on its way from the first channel F1 to the second channel F2 and raising its temperature. After preheating in the preheater 310, the heated mixed gas is supplied to the reboiler 330 through the sixth channel F6. In the reboiler 330, as described above, the heat from the heated mixed gas supplied from the sixth channel F6 heats the rich absorbent liquid supplied from the liquid receiving tray 21 of the regeneration tower 3 via the eleventh channel F11, and then returns it to the bottom of the tower 3a.

[0112] Meanwhile, the mixed gas supplied to the reboiler 330 from the sixth channel F6, having completed its role as a heat source, is introduced to the cooler 340 via the seventh channel F7, where it is cooled before flowing to the gas-liquid separator 350A via the eighth channel F8. Within the gas-liquid separator 350A, the mixed gas is separated into carbon dioxide gas and condensate. The separated carbon dioxide gas is then discharged from the tenth channel F10. The separated condensate passes through the ninth channel F9 and is reintroduced into the regeneration tower 3 from the fourth nozzle 28.

[0113] Of the first to fourteenth flow paths F14 described above, both the fourth flow path F4 and the fifth flow path F5 are made of stainless steel. However, for the other piping, if the fluid flowing inside is at high temperature and high pressure, piping made of carbon steel or stainless steel may be used. In this case, it is more preferable to use piping made of carbon steel when the fluid flowing inside is only a gas, while it is more preferable to use piping made of stainless steel when the fluid flowing inside is a liquid or a gas-liquid mixture.

[0114] Incidentally, as mentioned above, compressors generally come in oil-lubricated and oil-free types, and the compressor 320 in this embodiment uses an oil-free type. The reason for this is that, for example, if an oil-lubricated compressor 320 were used, there would be a risk of oil mist being mixed into the heated mixed gas that passes through this compressor 320. Therefore, a non-oil-lubricated compressor is adopted, but this presents another problem: its sealing characteristics are inferior to those of an oil-lubricated compressor, making it difficult to increase the compression ratio. Consequently, simply adopting a non-oil-lubricated compressor 320 may not be sufficient to heat the mixed gas to the required temperature, resulting in insufficient heat supply to the heater 330. And if there is such a lack of heat, the temperature of the heating fluid supplied to the regeneration tower 3 will naturally not be sufficient, which may hinder the operation of the regeneration tower 3.

[0115] Therefore, in the heating device 300 of this embodiment, a heated mixed gas, which has been heated by compression in the compressor 320, is supplied to the preheater 310 as a preheat source, and self-heat regeneration is employed to preheat the mixed gas passing through the preheater 310 using this preheat source. With this configuration, by pre-heating the temperature of the mixed gas before compression, the amount of compression required to raise it to the required temperature at the discharge port of the compressor 320 can be reduced. As a result, the compression ratio required of the compressor 320 is relaxed, and the discharge pressure of the compressor 320 can be reduced. Therefore, it is possible to raise the temperature of the heated mixed gas to the required temperature while lowering the discharge pressure of the compressor 320.

[0116] In addition to this self-heat regeneration, the heating device 300 of this embodiment is also characterized by having the fourth flow path F4 and the fifth flow path F5 described above. To explain this further, firstly, as described above, the heating device 300 of this embodiment employs self-heat regeneration, supplying a portion of the heat contained in the heated mixed gas discharged from the compressor 320 to the mixed gas before it is taken into the compressor 320 via the preheater 310. As a result, a heat circulation path is formed in which the heat flows out of the compressor 320, through the third flow path F3, the preheater 310, and then back to the compressor 320 via the second flow path F2. In this circulation path, some heat accumulation may occur during the self-heat regeneration process, but this amount of heat accumulation can be suppressed by using either or both of the fourth flow path F4 and the fifth flow path F5.

[0117] In other words, when using the fourth channel F4, the mixed gas flowing through the first channel F1 is bypassed by the preheater 310 and flows through the second channel F2, thereby reducing or eliminating the amount of heat received by the preheater 310. Therefore, it is possible to prevent an excessive increase in the amount of heat stored in the above circulation path. Similarly, when using the fifth flow path F5, the heated mixed gas compressed and heated by the compressor 320 can be bypassed by the preheater 310 and flowed to the sixth flow path F6, thereby reducing or eliminating the flow rate of the preheat source supplied to the preheater 310. This prevents an excessive increase in the amount of heat stored in the above circulation path. Thus, by limiting the amount of heat received when adjusting using the fourth flow path F4, and limiting the amount of heating when adjusting using the fifth flow path F5, it is possible to prevent excessive heat accumulation in the circulation path. The control of heat received and the control of heating may be performed either individually or simultaneously. In other words, although this embodiment illustrates the case where the fourth channel F4 and the fifth channel F5 are provided together, the configuration is not limited to this. For example, the fifth channel F5 may be omitted and only the heat received by the fourth channel F4 may be adjusted, or the fourth channel F4 may be omitted and only the heating amount by the fifth channel F5 may be adjusted. Alternatively, as shown in Figure 8, the fourth channel F4 and the fifth channel F5 may be provided together, and the heat received by the fourth channel F4 and the heating amount by the fifth channel F5 may be adjusted simultaneously or at an appropriate timing.

[0118] In the fourth flow path F4, the flow rate of the mixed gas flowing from the first flow path F1 to the preheater 310 and the flow rate of the mixed gas flowing from the first flow path F1 to the fourth flow path F4, bypassing the preheater 310, may be adjusted as appropriate, based on the state of the fluid (fluid temperature, fluid pressure) flowing at each position in the circulation path. Alternatively, flow path switching control may be performed so that all (100%) of the mixed gas flowing through the first flow path F1 flows only to one of the fourth flow path F4 and the preheater 310, and not to the other. Similarly, in the fifth flow path F5, the flow rate of the heated mixed gas flowing through the third flow path F3 and the flow rate of the heated mixed gas that bypasses the preheater 310 by flowing through the sixth flow path F6 via the fifth flow path F5 may be adjusted as appropriate, referring to the state of the fluid (fluid temperature, fluid pressure) flowing through each position of the heating device 300. Alternatively, flow path switching control may be performed so that all (100%) of the heated mixed gas compressed by the compressor 320 flows only through one of the fifth flow path F5 and the third flow path F3, and not through the other. Specific control methods that refer to the state of the fluid (fluid temperature, fluid pressure) flowing through the above circulation path will be described later as the first to sixth modified examples based on Figures 9 to 14.

[0119] The main points of the heating device 300 described above are summarized below. In other words, the heating device 300 of this embodiment is A reboiler (heater) 330 that uses a mixed gas discharged from the top 3b of the regeneration tower (fluid supply source) 3 as the heating fluid, heats the rich absorbent liquid (fluid to be heated) discharged from the liquid receiving tray 21 of the regeneration tower 3, A preheater 310 introduces the mixed gas from the top 3b of the regeneration tower 3 via the first flow path F1, A compressor 320 is connected to the downstream side of the preheater 310 via a second flow path F2, A third flow path F3 supplies at least a portion of the heated mixed gas compressed by the compressor 320 to the preheater 310 as a preheat source, The reboiler 330 introduces the heated mixed gas, which has been discharged from the third flow path F3 via the preheater 310, as the heating fluid. It is equipped with.

[0120] According to the heating device 300 described above, the mixed gas introduced into the preheater 310 from the top 3b of the regeneration tower 3 via the first flow path F1 is preheated and its temperature rises before being introduced into the compressor 320 via the second flow path F2. Subsequently, the mixed gas introduced into the compressor 320 is further heated by compression by the compressor 320 and then introduced into the preheater 310 via the third flow path F3. In the preheater 310, the heat from the heated mixed gas introduced via the third flow path F3 is used as a preheating source to preheat the mixed gas moving from the first flow path F1 through the second flow path F2 to the compressor 320. Therefore, the temperature of the gas mixture can be raised in advance before introducing it into the compressor 320. As a result, the amount of work required for the compressor 320 to compress the gas to the temperature needed for use as a heating fluid in the reboiler 330 can be reduced. Thus, the compression ratio requirements for the compressor 320 are relaxed, and an oil-free compressor 320 can be used.

[0121] Furthermore, the heating device 300 of this embodiment is The system further includes a fourth channel F4 that connects the first channel F1 and the second channel F2, bypassing the preheater 310. With this configuration, at least a portion of the mixed gas flowing from the first channel F1 through the second channel F2 to the compressor 320 can be passed through the fourth channel F4 as needed, allowing it to flow to the compressor 320 without preheating by the preheater 310. Therefore, by adjusting the flow rate of the mixed gas that bypasses the preheater 310 by flowing through the fourth channel F4 as needed, the temperature of the mixed gas supplied to the compressor 320 can be controlled to an appropriate temperature. In other words, the heat from the heated mixed gas heated by the compressor 320 moves from the downstream side of the compressor 320, passes through the third channel F3 to the preheater 310, and is then supplied to the mixed gas being preheated in the preheater 310 before returning to the compressor 320. However, by utilizing the fourth channel F4 which bypasses the preheater 310, the amount of preheating can be kept low or even eliminated. This makes it possible to suppress heat accumulation before and after the compressor 320.

[0122] Furthermore, the heating device 300 of this embodiment is The system further includes a fifth flow path F5 that connects the downstream side of the compressor 320 and the reboiler 330 via a sixth flow path F6. With this configuration, the heated mixed gas after being heated in the compressor 320 can be sent to the reboiler 330 via the fifth flow path F5 and the sixth flow path F6, allowing for more flexible preheating control of the mixed gas introduced into the compressor 320. For example, by diverting at least a portion of the heated mixed gas after being heated in the compressor 320 to the fifth flow path F5, the amount of heated mixed gas sent to the preheater 310 can be reduced. This allows for keeping the preheating amount low or even eliminating preheating altogether. This suppresses heat accumulation in the circulation path.

[0123] Furthermore, the carbon dioxide gas recovery system 2000 of this embodiment is An absorption tower 2 is formed by introducing and bringing into contact a gas to be separated containing carbon dioxide gas and a lean absorbent, thereby absorbing the carbon dioxide gas in the gas to be separated into the lean absorbent to produce a rich absorbent. A rich absorbent is supplied from absorption tower 2, and a regeneration tower 3 regenerates the rich absorbent into a lean absorbent by heating it and separating carbon dioxide gas. A heating device 300 heats the rich absorption liquid that is being drawn out of the regeneration tower 3 and reintroduced into the regeneration tower 3, Equipped with, The fluid supply source that flows the mixed gas into the first channel F1 is the regeneration tower 3. The fluid introduced from the fluid supply source is a mixed gas of carbon dioxide gas and the vapor components of the solute and solvent of the rich absorbent, which is discharged from the regeneration tower 3. The fluid to be heated is the absorbent liquid. This configuration allows for the recovery of carbon dioxide gas and the generation of decarbonated gas without using a heat source such as steam in the reboiler 330.

[0124] Furthermore, in the carbon dioxide gas recovery system 2000 of this embodiment, The compressor 320 may be driven by electricity derived from renewable energy. In this case, by using electricity derived from renewable energy as the power source for the compressor 320, it becomes possible to further enhance the effect of reducing environmental impact in addition to the effect of self-heat regeneration.

[0125] <First variation> In the carbon dioxide gas recovery system 2000, the heating device 400 shown in Figure 9 may be used instead of the heating device 300 shown in Figure 8. In this modified example, the amount of preheating in the preheater 310 is controlled based on the temperature and pressure information of the heated mixed gas discharged from the compressor 320. The heating device 400 of this modified example includes a first acquisition unit S1 at the discharge port of the compressor 320 or in the piping connected thereto, which acquires temperature information corresponding to the temperature of the heated mixed gas immediately after it has been compressed by the compressor 320, and pressure information corresponding to the pressure. An example of this first acquisition unit S1 is a combination of a thermometer such as a thermocouple and a pressure gauge equipped with a piezoelectric element.

[0126] Furthermore, the heating device 400 of this modified example includes a first flow control unit C1 instead of the first bypass volume control valve located downstream of the connection point p1. This first flow control unit C1 controls the flow rate of the mixed gas flowing through the fourth flow path F4 according to the temperature information and pressure information obtained by the first acquisition unit S1. As shown by the dashed line in Figure 9, the first flow control unit C1 has a communication function that can acquire temperature information and pressure information from the first acquisition unit S1 by wired or wireless communication, and a control function that adjusts its own valve opening based on the acquired temperature information and pressure information. With this configuration, the temperature information and pressure information acquired by the first acquisition unit S1 is transmitted directly to the first flow control unit C1. The first flow control unit C1 then adjusts itself to the required valve opening based on the acquired temperature information and pressure information. This controls the flow rate of the mixed gas flowing from the first flow path F1 that is directed towards the preheater 310 and the flow rate that is directed towards the fourth flow path F4 and bypasses the preheater 310.

[0127] Alternatively, the control device may be connected to the first acquisition unit S1 and the first flow control unit C1 via a communication line such as a wired or wireless connection. In this case, the temperature and pressure information acquired by the first acquisition unit S1 is first transmitted to the control device. The control device then transmits the required valve opening to the first flow control unit C1 based on the acquired temperature and pressure information. The first flow control unit C1 then adjusts itself to the valve opening corresponding to the received valve opening. This controls the flow rate of the mixed gas flowing from the first flow path F1 that goes towards the preheater 310 and the flow rate that goes towards the fourth flow path F4 and bypasses the preheater 310. Therefore, with this modified configuration, it is possible to reliably prevent an excessive increase in the amount of heat stored in the heat circulation path described above, which goes from the compressor 320, through the third flow path F3, the preheater 310, and the second flow path F2, and then back to the compressor 320.

[0128] <Second variation> In the carbon dioxide gas recovery system 2000, the heating device 500 shown in Figure 10 may be used instead of the heating device 300 shown in Figure 8. In this modified example, the amount of preheating in the preheater 310 is controlled based on the temperature information of the mixed gas before the intake port of the compressor 320. In this modified heating device 500, a second acquisition unit S2 is provided on the piping forming a combined flow path F2a, which is formed between the connection point p2, which is the point where the second flow path F2 merges with the fourth flow path F4, and the suction port of the compressor 320. This unit acquires temperature information corresponding to the temperature of the mixed gas immediately before it is compressed by the compressor 320. An example of this second acquisition unit S2 is a thermometer such as a thermocouple.

[0129] Furthermore, the heating device 500 of this modified example includes a first flow control unit C1 instead of the first bypass amount control valve located downstream of the connection point p1. This first flow control unit C1 controls the flow rate of the mixed gas flowing through the fourth flow path F4 according to the temperature information obtained by the second acquisition unit S2. As shown by the dashed line in Figure 10, the first flow control unit C1 has a communication function that can acquire temperature information from the second acquisition unit S2 by wired or wireless communication, and a control function that adjusts its own valve opening based on the acquired temperature information. With this configuration, the temperature information acquired by the second acquisition unit S2 is transmitted directly to the first flow control unit C1. The first flow control unit C1 then adjusts itself to the required valve opening based on the acquired temperature information. This controls the flow rate of the mixed gas flowing from the first flow path F1 that is directed towards the preheater 310 and the flow rate that is directed towards the fourth flow path F4 and bypasses the preheater 310.

[0130] Alternatively, the control device may be connected to the second acquisition unit S2 and the first flow control unit C1 via a wired or wireless communication line. In this case, the temperature information acquired by the second acquisition unit S2 is first transmitted to the control device. The control device then transmits the required valve opening to the first flow control unit C1 based on the acquired temperature information. The first flow control unit C1 then adjusts the valve to an opening corresponding to the received valve opening. This controls the flow rate of the mixed gas flowing from the first flow path F1 that goes towards the preheater 310 and the flow rate that goes towards the fourth flow path F4 and bypasses the preheater 310. Therefore, according to the configuration of this modified example, it is possible to reliably prevent an excessive increase in the amount of heat stored in the heat circulation path described above, which exits from the compressor 320, passes through the third flow path F3, the preheater 310, and the second flow path F2, and returns to the compressor 320.

[0131] <Third variation> In the carbon dioxide gas recovery system 2000, the heating device 600 shown in Figure 11 may be used instead of the heating device 300 shown in Figure 8. In this modified example, the amount of preheating in the preheater 310 is controlled based on the temperature information of the mixed gas in the fourth flow path F4. The heating device 600 of this modified example includes a third acquisition unit S3 in the piping forming the fourth flow path F4, which acquires temperature information corresponding to the temperature of the mixed gas flowing through the fourth flow path F4. An example of this third acquisition unit S3 is a thermometer such as a thermocouple.

[0132] Furthermore, the heating device 600 of this modified example includes a first flow rate control unit C1 instead of the first bypass volume control valve provided at the connection point p1. This first flow rate control unit C1 controls the flow rate of the mixed gas flowing through the fourth flow path F4 according to the temperature information obtained by the third acquisition unit S3. As shown by the dashed line in Figure 11, the first flow rate control unit C1 has a communication function that can acquire temperature information from the third acquisition unit S3 by wired or wireless communication, and a control function that adjusts its own valve opening based on the acquired temperature information. With this configuration, the temperature information acquired by the third acquisition unit S3 is transmitted directly to the first flow rate control unit C1. The first flow rate control unit C1 then adjusts itself to the required valve opening based on the acquired temperature information. This controls the flow rate of the mixed gas flowing from the first flow path F1 that is directed towards the preheater 310 and the flow rate that is directed towards the fourth flow path F4 and bypasses the preheater 310.

[0133] Alternatively, the control device may be connected to the third acquisition unit S3 and the first flow control unit C1 via a communication line such as a wired or wireless connection. In this case, the temperature information acquired by the third acquisition unit S3 is first transmitted to the control device. The control device then transmits the required valve opening to the first flow control unit C1 based on the acquired temperature information. The first flow control unit C1 then adjusts itself to the valve opening corresponding to the received valve opening. This controls the flow rate of the mixed gas flowing from the first flow path F1 that goes towards the preheater 310 and the flow rate that goes towards the fourth flow path F4 and bypasses the preheater 310. Therefore, according to the configuration of this modified example, it is possible to reliably prevent an excessive increase in the amount of heat stored in the heat circulation path described above, which exits from the compressor 320, passes through the third flow path F3, the preheater 310, and the second flow path F2, and returns to the compressor 320.

[0134] <Fourth variation> In the carbon dioxide gas recovery system 2000, the heating device 700 shown in Figure 12 may be used instead of the heating device 300 shown in Figure 8. In this modified example, the amount of preheating in the preheater 310 is controlled based on the temperature information of the mixed gas in the range from when it leaves the preheater 310 until it reaches the inlet of the confluence channel F2a. The heating device 700 of this modified example includes a fourth acquisition unit S4 that acquires temperature information corresponding to the temperature of the mixed gas passing through the connection point p2, which is the point where the heated fluid outlet of the preheater 310 and the fourth flow path F4 on the second flow path F2 meet. An example of this fourth acquisition unit S4 is a thermometer such as a thermocouple.

[0135] Furthermore, the heating device 700 of this modified example includes a first flow rate control unit C1 instead of the first bypass amount control valve provided at the connection point p1. This first flow rate control unit C1 controls the flow rate of the mixed gas flowing through the fourth flow path F4 according to the temperature information obtained by the fourth acquisition unit S4. As shown by the dashed line in Figure 12, this first flow rate control unit C1 has a communication function that can acquire temperature information from the fourth acquisition unit S4 by wired or wireless communication, and a control function that adjusts its own valve opening based on the acquired temperature information. With this configuration, the temperature information acquired by the fourth acquisition unit S4 is transmitted directly to the first flow rate control unit C1. The first flow rate control unit C1 then adjusts itself to the required valve opening based on the acquired temperature information. This controls the flow rate of the mixed gas flowing from the first flow path F1 that is directed towards the preheater 310 and the flow rate that is directed towards the fourth flow path F4 and bypasses the preheater 310.

[0136] Alternatively, the control device may be connected to the fourth acquisition unit S4 and the first flow control unit C1 via a wired or wireless communication line. In this case, the temperature information acquired by the fourth acquisition unit S4 is first transmitted to the control device. The control device then transmits the required valve opening to the first flow control unit C1 based on the acquired temperature information. The first flow control unit C1 then adjusts itself to the valve opening corresponding to the received valve opening. This controls the flow rate of the mixed gas flowing from the first flow path F1 that goes towards the preheater 310 and the flow rate that goes towards the fourth flow path F4 and bypasses the preheater 310. Therefore, according to the configuration of this modified example, it is possible to reliably prevent an excessive increase in the amount of heat stored in the heat circulation path described above, which exits from the compressor 320, passes through the third flow path F3, the preheater 310, and the second flow path F2, and returns to the compressor 320.

[0137] <Fifth variation> In the carbon dioxide gas recovery system 2000, the heating device 800 shown in Figure 13 may be used instead of the heating device 300 shown in Figure 8. In this modified example, the amount of preheating in the preheater 310 is controlled based on the temperature and pressure information of the heated mixed gas flowing through the third flow path F3. The heating device 800 in this modified example is equipped with a fifth data acquisition unit S5 in the piping forming the third flow path F3, which acquires temperature information corresponding to the temperature of the heated mixed gas before it reaches the preheater 310 and pressure information corresponding to the pressure. An example of this fifth data acquisition unit S5 is a combination of a thermometer such as a thermocouple and a pressure gauge equipped with a piezoelectric element.

[0138] Furthermore, the heating device 800 of this modified example includes a first flow control unit C1 instead of the first bypass volume control valve provided at connection point p1. This first flow control unit C1 controls the flow rate of the mixed gas flowing through the fourth flow path F4 according to the temperature information and pressure information obtained by the fifth acquisition unit S5. As shown by the dashed line in Figure 13, this first flow control unit C1 has a communication function that can acquire temperature information and pressure information from the fifth acquisition unit S5 by wired or wireless communication, and a control function that adjusts the valve opening itself based on the acquired temperature information and pressure information. With this configuration, the temperature information and pressure information acquired by the fifth acquisition unit S5 is directly transmitted to the first flow control unit C1. The first flow control unit C1 then adjusts itself to the required valve opening based on the acquired temperature information and pressure information. This controls the flow rate of the mixed gas flowing from the first flow path F1 that is directed toward the preheater 310 and the flow rate that is directed toward the fourth flow path F4 and bypasses the preheater 310.

[0139] Alternatively, the control device may be connected to the fifth acquisition unit S5 and the first flow control unit C1 via a communication line such as a wired or wireless connection. In this case, the temperature and pressure information acquired by the fifth acquisition unit S5 is first transmitted to the control device. The control device then transmits the required valve opening to the first flow control unit C1 based on the acquired temperature and pressure information. The first flow control unit C1 then adjusts itself to the valve opening corresponding to the received valve opening. This controls the flow rate of the mixed gas flowing from the first flow path F1 that goes towards the preheater 310 and the flow rate that goes towards the fourth flow path F4 and bypasses the preheater 310. Therefore, according to the configuration of this modified example, it is possible to reliably prevent an excessive increase in the amount of heat stored in the heat circulation path described above, which exits from the compressor 320, passes through the third flow path F3, the preheater 310, and the second flow path F2, and returns to the compressor 320.

[0140] <Sixth variation> In the carbon dioxide gas recovery system 2000, the heating device 900 shown in Figure 14 may be used instead of the heating device 300 shown in Figure 8. In this modified example, the amount of preheat supplied to the preheater 310 as a preheat source from the heated mixed gas discharged from the compressor 320 is controlled based on the temperature and pressure information of the heated mixed gas discharged from the compressor 320. The heating device 900 of this modified example includes a sixth data acquisition unit S6 at the discharge port of the compressor 320 or in the piping connected thereto, which acquires temperature information corresponding to the temperature of the heated mixed gas immediately after it has been compressed by the compressor 320, and pressure information corresponding to the pressure. An example of this sixth data acquisition unit S6 is a combination of a thermometer such as a thermocouple and a pressure gauge equipped with a piezoelectric element.

[0141] Furthermore, the heating device 900 of this modified example includes a second flow control unit C2 that controls the flow rate of the heated mixed gas discharged from the outlet of the compressor 320 to the third flow path F3 and the flow rate of the heated mixed gas to the fifth flow path F5, according to the temperature information and pressure information obtained in the sixth acquisition unit S6. The second flow control unit C2 includes a first valve C21 connected to the piping forming the third flow path F3 and a second valve C22 connected to the piping forming the fifth flow path F5. By appropriately synchronously controlling the opening degrees of these two valves, the flow rate of the heated mixed gas discharged from the outlet of the compressor 320 to the third flow path F3 and the flow rate of the heated mixed gas to the fifth flow path F5 can be controlled.

[0142] The second flow control unit C2 has a communication function that can acquire temperature and pressure information from the sixth acquisition unit S6 via wired or wireless communication, and a control function that adjusts the valve opening of the first valve C21 and the second valve C22 based on the acquired temperature and pressure information. With this configuration, the temperature and pressure information acquired by the sixth acquisition unit S6 is directly transmitted to the second flow control unit C2. The second flow control unit C2 then adjusts the valve opening of the first valve C21 and the second valve C22 based on the acquired temperature and pressure information. This controls the flow rate of the heated mixed gas discharged from the outlet of the compressor 320 that flows into the third flow path F3 as a preheating source, and the flow rate that flows from the fifth flow path F5 through the sixth flow path F6 to the reboiler 330.

[0143] Alternatively, the control device may be connected to the sixth data acquisition unit S6 and the second flow control unit C2 via a wired or wireless communication line. In this case, the sixth data acquisition unit S6 first transmits the acquired temperature and pressure information to the control device. The control device then transmits the valve openings of the first valve C21 and the second valve C22 to the second flow control unit C2 based on the acquired temperature and pressure information. The second flow control unit C2 then adjusts the valve openings of the first valve C21 and the second valve C22 based on the acquired temperature and pressure information. This controls the flow rate of the heated mixed gas discharged from the outlet of the compressor 320 that flows into the third flow path F3 as a preheating source, and the flow rate that is directed to the reboiler 330 via the fifth flow path F5 and the sixth flow path F6 without going to the preheater 310. Therefore, according to the configuration of this modified example, it is possible to reliably prevent an excessive increase in the amount of heat stored in the heat circulation path described above, which exits from the compressor 320, passes through the third flow path F3, the preheater 310, and the second flow path F2, and returns to the compressor 320. In this modified example, the flow rate of the heated mixed gas flowing through the third channel F3 and the flow rate of the heated mixed gas flowing through the fifth channel F5 are controlled based on the temperature and pressure information of the heated mixed gas at the location where it is discharged from the compressor 320. Alternatively, the location where the temperature and pressure information of the heated mixed gas is acquired may be the third channel F3. Or, instead of the heated mixed gas discharged from the compressor 320, the flow rate of the heated mixed gas flowing through the third channel F3 and the flow rate of the heated mixed gas flowing through the fifth channel F5 may be adjusted based on the temperature information of the mixed gas flowing through one of the second channel F2, the combined channel F2a, or the fourth channel F4. [Explanation of Symbols]

[0144] 2. Absorption Tower 3 Regeneration tower (fluid supply source) 100 Distillation Column (Unit Operating Device) 200 Carbon Dioxide Gas Recovery System (Unit Operating Device) 300 Heating device 310 Preheater 320 Compressor 330 Reboiler (heater) 340 Cooler 350 Branch section 360 Branching point 400 Heating device (first modified example) 500 Heating device (second modified example) 600 Heating device (third modified example) 700 Heating device (fourth modified example) 800 Heating device (5th modified example) 900 Heating device (6th modified example) 1000 Distillation Systems (Unit Operating Systems) 2000 Carbon Dioxide Gas Recovery System (Unit Operation System) C1 First Flow Control Unit C2 Second flow control unit F1 First channel F2 Second channel F2a convergence road F3 Third channel F4 Fourth channel F5 Fifth channel F6 6th flow path S1, S5 First Acquisition Section S2 Second Acquisition Section S3 Third Acquisition Section S4, Part 4 S6, 5th Acquisition Section

Claims

1. A device for heating a fluid to be heated using a heater that uses a fluid introduced from a fluid supply source as the heating fluid, A preheater that introduces the fluid from the fluid supply source through a first flow path, A compressor connected to the downstream side of the preheater via a second flow path, A third channel supplies at least a portion of the fluid compressed by the compressor to the preheater as a preheat source, The heater introduces the fluid that has been led out from the third channel through the preheater as the heating fluid and heats the fluid to be heated, A heating device characterized by comprising the following features.

2. The heating apparatus according to claim 1, further comprising a fourth flow path that connects the first flow path and the second flow path by bypassing the preheater.

3. A first acquisition unit acquires temperature information corresponding to the temperature and pressure information corresponding to the pressure of the fluid flowing through the third channel or the fluid compressed by the compressor, A first flow control unit controls the flow rate of the fluid flowing through the fourth channel according to the temperature information and the pressure information, The heating device according to claim 2, further comprising:

4. The second flow path includes a confluence channel that combines the fluid led out from the downstream side of the preheater and the fluid flowing through the fourth flow path and introduces them to the upstream side of the compressor. A second acquisition unit acquires temperature information corresponding to the temperature of the fluid flowing through the aforementioned confluence channel, A first flow control unit controls the flow rate of the fluid flowing through the fourth channel according to the temperature information, The heating device according to claim 2, further comprising:

5. A third acquisition unit acquires temperature information corresponding to the temperature of the fluid flowing through the fourth channel, A first flow control unit controls the flow rate of the fluid flowing through the fourth channel according to the temperature information, The heating device according to claim 2, further comprising:

6. The second flow path includes a confluence channel that combines the fluid led out from the downstream side of the preheater and the fluid flowing through the fourth flow path and introduces them to the upstream side of the compressor. A fourth acquisition unit acquires temperature information corresponding to the temperature of the fluid downstream of the preheater and before it reaches the confluence channel, A first flow control unit controls the flow rate of the fluid flowing through the fourth channel according to the temperature information, The heating device according to claim 2, further comprising:

7. The heating apparatus according to claim 2, further comprising a fifth flow path connecting the downstream side of the compressor and the heater.

8. A fifth acquisition unit acquires temperature information corresponding to the temperature and pressure information corresponding to the pressure of the fluid flowing in a range downstream of the compressor and upstream of the third flow path, A second flow control unit controls the flow rate of the fluid flowing from the downstream side of the compressor to the third flow path and the flow rate of the fluid flowing from the downstream side of the compressor to the fifth flow path, in accordance with the temperature information and the pressure information. The heating device according to claim 7, further comprising:

9. The heating apparatus according to claim 1, further comprising a fifth flow path connecting the downstream side of the compressor and the heater.

10. A first acquisition unit acquires temperature information corresponding to the temperature and pressure information corresponding to the pressure of the fluid flowing in a range downstream of the compressor and upstream of the third flow path, A second flow control unit controls the flow rate of the fluid flowing from the downstream side of the compressor to the third flow path and the flow rate of the fluid flowing from the downstream side of the compressor to the fifth flow path, in accordance with the temperature information and the pressure information. The heating device according to claim 9, further comprising:

11. A second acquisition unit acquires temperature information corresponding to the temperature of the fluid before compression that flows into the compressor, A second flow control unit controls the flow rate of the fluid flowing from the downstream side of the compressor to the third flow path and the flow rate of the fluid flowing from the downstream side of the compressor to the fifth flow path, in accordance with the temperature information. The heating device according to claim 9, further comprising:

12. The compressor is powered by electricity derived from renewable energy. A heating apparatus according to any one of claims 1 to 11.

13. A heating device according to any one of claims 1 to 11, A unit operation apparatus that uses the heated fluid heated by the heater to perform at least one of the following operations on the unit operation fluid: distillation, stripping, concentration, drying, and evaporation. A unit manipulation system characterized by comprising the following features.

14. The compressor is powered by electricity derived from renewable energy. The unit manipulation system according to feature 13.

15. An absorption tower is provided, which introduces and brings into contact a gas to be separated containing carbon dioxide gas and a lean absorbent, thereby absorbing the carbon dioxide gas in the gas to be separated into the lean absorbent to produce a rich absorbent. A regeneration tower receives the rich absorbent from the absorption tower and regenerates the lean absorbent by heating the rich absorbent and separating the carbon dioxide gas. A heating device for heating the rich absorption liquid that is being drawn out of the regeneration tower and reintroduced into the regeneration tower, Equipped with, The heating device is the heating device described in any one of claims 1 to 11. The fluid supply source is the regeneration tower, The fluid introduced from the fluid supply source is a mixed gas of carbon dioxide gas and the vapor components of the solute and solvent of the rich absorbent, which is discharged from the regeneration tower. The fluid to be heated is the rich absorbent liquid. A carbon dioxide gas recovery system characterized by the following features.

16. The compressor is powered by electricity derived from renewable energy. The carbon dioxide gas recovery system according to claim 15, characterized in that it is as described above.

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