Generation system and operation method for generation system
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- KANADEVIA CORP
- Filing Date
- 2025-09-19
- Publication Date
- 2026-07-02
Smart Images
Figure JP2025033017_02072026_PF_FP_ABST
Abstract
Description
Generation system and method for operating a generation system
[0001] The present invention relates to a generation system and a method for operating a generation system.
[0002] For example, Patent Document 1 discloses a technique related to a generation apparatus and a generation method for generating a product gas and generated water in which the product gas is dissolved by an exothermic reaction of reactants in a gaseous state.
[0003] Japanese Patent No. 6984098
[0004] By the above exothermic reaction, in addition to the product gas, generated water is secondarily generated. When the generated water is condensed, dehydrated, and removed, the product gas is dissolved in the condensed generated water. When the product gas is a combustible gas, it is necessary to consider safety when treating the generated water. In order to avoid this problem, it is conceivable to remove the dissolved gas in the generated water by storing the generated water in a tank and volatilizing the product gas (dissolved gas) dissolved in the generated water with a blower. In this method, in order to surely remove the dissolved gas in the generated water, it is premised that the amount of the generated water is maximum, and a mechanism for adjusting the energy for removing the dissolved gas in the generated water is not used. However, since the amount of the generated water varies depending on the operating state, the performance of the separation mechanism, etc., when the amount of the generated water is less than the set maximum amount, the energy efficiency for removing the dissolved gas in the generated water becomes low.
[0005] An object of the present invention is to provide a technique capable of improving the energy efficiency for removing the dissolved gas in the generated water.
[0006] The present invention, which solves the above problems, is a production system comprising: a production unit that produces product gas and generated water by a catalytic reaction of a raw material gas and delivers the product gas and generated water; a degassing unit that removes dissolved gas dissolved in the generated water delivered from the production unit; a measuring unit that measures the amount of generated water flowing into the degassing unit; and a control unit that determines a control amount for the removal of dissolved gas in the degassing unit based on the amount of generated water flowing into the degassing unit and controls the degassing unit based on the control amount. In the above production system, the control amount for the removal of dissolved gas in the degassing unit is determined based on the amount of generated water flowing into the degassing unit. If the amount of generated water flowing into the degassing unit is large, the control amount for the removal of dissolved gas in the degassing unit can be increased, and if the amount of generated water flowing into the degassing unit is small, the control amount for the removal of dissolved gas in the degassing unit can be decreased. By controlling the degassing unit based on a control amount corresponding to the amount of generated water flowing into the degassing unit, the energy efficiency for removing dissolved gas in the generated water can be improved.
[0007] The degassing unit removes dissolved gas from the generated water by blowing air into the generated water, and the control amount includes the amount of air blown into the generated water. If the amount of generated water flowing into the degassing unit is large, the amount of air blown into the generated water can be increased, and if the amount of generated water flowing into the degassing unit is small, the amount of air blown into the generated water can be decreased. By controlling the degassing unit based on the amount of air corresponding to the amount of generated water flowing into the degassing unit, the energy efficiency for removing dissolved gas from the generated water can be improved.
[0008] The degassing unit removes the dissolved gas from the generated water by heating it, and the control amount includes the amount of heat required to heat the generated water. If the amount of generated water flowing into the degassing unit is large, the amount of heat required to heat the generated water can be increased, and if the amount of generated water flowing into the degassing unit is small, the amount of heat required to heat the generated water can be decreased. By controlling the degassing unit based on the amount of heat required according to the amount of generated water flowing into the degassing unit, the energy efficiency for removing dissolved gas from the generated water can be improved.
[0009] The degassing unit has a heat exchanger that heats the generated water by exchanging heat between a heat transfer medium heated by a heat source and the generated water. This improves the energy efficiency for removing dissolved gases from the generated water in the degassing unit having a heat exchanger.
[0010] If the temperature of the heat transfer medium before it flows into the heat exchanger is below a predetermined temperature, the heat transfer medium is heated by a heater. This improves the reliability of removing dissolved gases from the generated water, even if the temperature of the heat transfer medium before it flows into the heat exchanger is below a predetermined temperature.
[0011] The heat source is the generation unit, which is heated by the reaction heat during the generation of the product gas. This allows the heat transfer medium to be heated by the generation unit, which is heated by the reaction heat during the generation of the product gas.
[0012] The above-described generation system includes a condenser that condenses and liquefies the generated water discharged from the generation unit, a separation unit that separates the generated water liquefied by the condenser from the product gas and discharges the generated water, and a detection unit that detects whether the generated water discharged from the separation unit contains more than a specified value of bubbles. The generated water discharged from the separation unit flows into the degassing unit. If the detection unit detects that the generated water contains more than the specified value of bubbles, the control unit stops the operation of the generation unit and the separation unit. If the generated water discharged from the separation unit contains more than the specified value of bubbles, there is a high possibility that a malfunction has occurred in the separation unit. If the detection unit detects that the generated water contains more than the specified value of bubbles, stopping the operation of the generation unit and the separation unit allows for repair or replacement of the separation unit.
[0013] Furthermore, the present invention relates to a method for operating a production system comprising: a production unit that produces product gas and generated water by a catalytic reaction of a raw material gas and delivers the product gas and generated water; and a degassing unit that removes dissolved gases dissolved in the generated water delivered from the production unit, wherein the method for operating a production system involves measuring the amount of generated water flowing into the degassing unit, determining a control amount for the removal of dissolved gases in the degassing unit based on the amount of generated water flowing into the degassing unit, and controlling the degassing unit based on the control amount.
[0014] According to the present invention, it is possible to improve the energy efficiency for removing dissolved gases from the generated water.
[0015] Figure 1 is a diagram showing the configuration of the generation system according to the embodiment. Figure 2 is a diagram showing an example of the mounting position of the sensor. Figure 3 is a diagram showing an example of the degassing section. Figure 4 is a diagram showing an example of the degassing section. Figure 5 is a diagram showing an example of the degassing section.
[0016] The embodiments of the present invention will be described below. The embodiments shown below are examples of embodiments of the present invention and do not limit the technical scope of the present invention to the following embodiments.
[0017] Figure 1 is a diagram of the configuration of a production system (production device) 100 according to an embodiment. The production system 100 shown in Figure 1 produces methane gas and water, which are product gases, through an exothermic reaction between gaseous hydrogen and carbon dioxide, which are raw material gases (reaction gases). Furthermore, the above chemical reaction is also a reversible reaction. The above exothermic reaction can be represented by the following chemical equation: CO ２ +4H ２ →CH ４ +2H ２ O ... (1)
[0018] The production system 100 comprises reactors 1 and 2 as a production section, economizers 3 and 4, gas cooling heat exchangers 5 and 6, liquid drainers 7 and 8, a raw material gas supply section 9, a storage tank 10, and a degassing section 11. The production system 100 includes a gas path 101 through which gas flows through reactors 1 and 2. Reactors 1 and 2, economizers 3 and 4, gas cooling heat exchangers 5 and 6, and the storage tank 10 are located in the gas path 101. The gas path 101 is also provided with piping and valves. In the production system 100 shown in Figure 1, the production section is composed of reactors 1 and 2, but the system is not limited to this configuration. The production section may have a configuration in which reactors 1 and 2 and other reactors. The production system 100 may have one production section or multiple production sections. The production system 100 may have one production section composed of reactors 1 and 2. The production system 100 may include a first production section composed of a reactor 1 and a second production section composed of a reactor 2. The production system 100 may further include a third production section composed of another reactor.
[0019] The raw material gas is supplied from the raw material gas supply unit 9 into the reactor 1. The reactor 1 produces the product gas through a catalytic reaction of the raw material gas. The raw material gas is, for example, hydrogen (H ２ ) and carbon dioxide (CO2) ２ ) is included. Reactor 1 and economizer 3 are connected, and economizer 3 is connected to raw material gas supply unit 9. Heat exchange takes place in economizer 3 between the raw material gas supplied from raw material gas supply unit 9 and the gas supplied from reactor 1. The gas supplied from reactor 1 is a mixed gas of product gas and unreacted raw material gas.
[0020] The economizer 3 and the gas cooling heat exchanger 5 are connected. Reactor 1 generates water (steam) through a catalytic reaction of the raw material gas. The gas cooling heat exchanger 5 condenses the water (steam) generated in reactor 1. That is, the gas cooling heat exchanger 5 condenses and liquefies the water (steam) discharged from reactor 1. The gas cooling heat exchanger 5 is an example of a condenser. The gas cooling heat exchanger 5 and the liquid drainer 7 are connected. The liquid drainer 7 separates the water (liquid) from the product gas and unreacted raw material gas. The liquid drainer 7 separates the water liquefied by the gas cooling heat exchanger 5 from the mixed gas (product gas and unreacted raw material gas) and discharges the water. The liquid drainer 7 is an example of a separation unit.
[0021] Reactor 2 is connected to economizer 4, and economizer 4 is connected to gas cooling heat exchanger 5. The product gas and unreacted raw material gas produced in reactor 1 are sent to reactor 2 via economizer 3, gas cooling heat exchanger 5, and economizer 4. Reactor 2 produces product gas through a catalytic reaction of the raw material gas. By producing product gas from unreacted raw material gas in reactor 2, the production system 100 is able to produce high-concentration product gas.
[0022] In the economizer 4, heat exchange takes place between the gas supplied from reactor 1 and the gas supplied from reactor 2. The gas supplied from reactor 2 is either the product gas or a mixture of the product gas and unreacted raw material gas.
[0023] The economizer 4 is connected to the gas cooling heat exchanger 6, and the gas cooling heat exchanger 6 is connected to the liquid drainer 8. The reactor 2 generates product water (steam) through a catalytic reaction of the raw material gas. That is, the gas cooling heat exchanger 6 condenses and liquefies the product water (steam) sent from the reactor 2. The gas cooling heat exchanger 6 is an example of a condenser. The liquid drainer 8 separates the product water (liquid) from the product gas. Alternatively, the liquid drainer 8 separates the product water (liquid) from the product gas and unreacted raw material gas. The liquid drainer 8 separates the product water liquefied by the gas cooling heat exchanger 6 from the product gas and sends out the product water. Alternatively, the liquid drainer 8 separates the product water liquefied by the gas cooling heat exchanger 6 from the mixed gas and sends out the product water. The liquid drainer 8 is an example of a separation unit.
[0024] The storage tank 10 stores the product gas. The product gas is sent from the gas cooling heat exchanger 6 to the storage tank 10. A removal unit may be placed between the gas cooling heat exchanger 6 and the storage tank 10. The product gas may be sent to the storage tank 10 after unreacted raw material gas has been removed by the removal unit.
[0025] Liquid drainer 7 is connected to degassing unit 11, and liquid drainer 8 is connected to degassing unit 11. Liquid drainer 7 supplies only the generated water condensed in the gas cooling heat exchanger 5 to the degassing unit 11. Liquid drainer 8 supplies only the generated water condensed in the gas cooling heat exchanger 6 to the degassing unit 11. Liquid drainers 7 and 8 may be, for example, float-type gas-liquid separators that have a float inside and perform gas-liquid separation using the difference in specific gravity between gas and liquid. The generated water discharged from liquid drainers 7 and 8 flows into the degassing unit 11. The degassing unit 11 removes dissolved gases from the generated water discharged from reactors 1 and 2. The dissolved gases removed from the generated water are released into the atmosphere, and the generated water from which the dissolved gases have been removed is discharged outside the system.
[0026] Reactors 1 and 2 are pre-filled with catalysts. Any catalyst that promotes reaction (1) may be used. The catalyst comprises, for example, a stabilized zirconia support and Ni supported on the stabilized zirconia support. The stabilized zirconia support has a tetragonal and / or cubic crystal structure in which the stabilizing element is solid-dissolved. Examples of the stabilizing element include at least one transition element selected from the group consisting of Mn, Fe, and Co.
[0027] The production system 100 includes a circulation path 102 through which a heat transfer medium circulates to regulate the temperature inside reactors 1 and 2. The heat transfer medium is, for example, heat transfer oil, but is not limited to this, and may also be water. The production system 100 includes a heater 12, a pump 13, a heat exchanger for the heat transfer medium 14, a cooling tower 15, and a cooling water circulation pump 16. Reactors 1 and 2, the heater 12, the pump 13, the heat exchanger for the heat transfer medium 14, the cooling tower 15, and the cooling water circulation pump 16 are located in the circulation path 102. The circulation path 102 is also provided with piping, valves, etc.
[0028] Reactors 1 and 2 are, for example, shell-and-tube type heat exchangers. A heat transfer medium can flow in and out of the shell of reactor 1 to exchange heat with the heat-generating part inside reactor 1. Similarly, a heat transfer medium can flow in and out of the shell of reactor 2 to exchange heat with the heat-generating part inside reactor 2. As the heat transfer medium flows into the shells of reactors 1 and 2, the heat transfer medium circulates within reactors 1 and 2, and the temperature inside reactors 1 and 2 is adjusted. The shells of reactor 1 and reactor 2 are connected by piping through which the heat transfer medium flows. Reactors 1 and 2 are not limited to shell-and-tube type heat exchangers; they may be plate type heat exchangers or other types of heat exchangers.
[0029] The shell of reactor 1 and the heater 12 are connected by piping through which a heat transfer medium flows. The heater 12 is capable of heating the heat transfer medium. The heat transfer medium heated by the heater 12 passes through reactor 1 and then through reactor 2.
[0030] The shell of reactor 2 and the heat exchanger 14 for the heat transfer medium are connected by piping through which the heat transfer medium flows. The heat exchanger 14 for the heat transfer medium cools the heat transfer medium that has passed through reactors 1 and 2. The heater 12 and the heat exchanger 14 for the heat transfer medium are connected by piping through which the heat transfer medium flows. A pump 13 is provided in the piping connecting the heater 12 and the heat exchanger 14 for the heat transfer medium to send the heat transfer medium cooled by the heat exchanger 14 to the heater 12. Control valves 17 and 18 are provided in the piping through which the heat transfer medium flows. By opening and closing the control valves 17 and 18, the heat transfer medium that has passed through reactors 1 and 2 can be sent to the heater 12 via the heat exchanger 14 for the heat transfer medium, or it can be sent to the heater 12 without passing through the heat exchanger 14 for the heat transfer medium.
[0031] The cooling tower 15 cools the cooling water that exchanges heat with the heat transfer medium in the heat transfer medium heat exchanger 14. For example, tap water supplied to the cooling tower 15 from outside the system may be used as the cooling water. The cooling water circulation pump 16 circulates the cooling water supplied into the cooling tower 15 between the heat transfer medium heat exchanger 14 and the cooling tower 15.
[0032] The generation system 100 includes a chiller 19. The chiller 19 cools the cooling water (refrigerant) used to condense the generated water in the gas cooling heat exchangers 5 and 6. The gas cooling heat exchangers 5 and 6 and the chiller 19 are interconnected by piping through which the cooling water flows. The cooling water cooled by the chiller 19 returns to the chiller 19 via the gas cooling heat exchangers 5 and 6. A cooling tower may be used instead of the chiller 19.
[0033] The generation system 100 includes a control unit 21. The control unit 21 determines a control amount for removing dissolved gas in the degassing unit 11 based on the amount of generated water flowing into the degassing unit 11, and controls the degassing unit 11 based on the determined control amount. The control unit 21 may increase the control amount for removing dissolved gas in the degassing unit 11 if the amount of generated water flowing into the degassing unit 11 is large. The control unit 21 may decrease the control amount for removing dissolved gas in the degassing unit 11 if the amount of generated water flowing into the degassing unit 11 is small. This makes it possible to increase the control amount for removing dissolved gas in the degassing unit 11 if the amount of generated water flowing into the degassing unit 11 is large, and decrease the control amount for removing dissolved gas in the degassing unit 11 if the amount of generated water flowing into the degassing unit 11 is small. By controlling the degassing unit 11 based on a control amount corresponding to the amount of generated water flowing into the degassing unit 11, the control unit 21 can improve the energy efficiency for removing dissolved gas in the generated water.
[0034] The control unit 21 is a controller that controls the overall operation of the generation system 100. The control unit 21 may also control only a part of the operation of the generation system 100. The control unit 21 may be a sequencer such as a PLC (Programmable Logic Controller). The control unit 21 may be configured using dedicated equipment or a general-purpose computer. The control unit 21 is equipped with hardware resources such as a processor (CPU), memory, storage, and a communication interface. The memory may be RAM. The storage may be a non-volatile storage device (e.g., ROM, flash memory). The functions of the control unit 21 are realized by loading programs stored in storage into memory and executing them using the processor. However, the configuration of the control unit 21 is not limited to these. For example, all or part of the functions of the control unit 21 may be configured using circuits such as ASICs or FPGAs, or all or part of the functions of the control unit 21 may be executed on a cloud server or other device.
[0035] The generation system 100 includes sensors 22 and 23. Sensor 22 is provided in the piping 24 connecting the liquid drainer 7 and the degassing section 11. Sensor 22 has a measuring unit that measures the amount of generated water discharged from the reactor 1 and flowing into the degassing section 11. The measuring unit of sensor 22 may be an ultrasonic flow meter that measures the flow rate of generated water flowing through the piping 24. The measuring unit of sensor 22 may also measure the amount of generated water flowing into the degassing section 11 based on the flow rate of generated water flowing through the piping 24. Data regarding the amount of generated water measured by the measuring unit of sensor 22 is sent to the control unit 21.
[0036] Sensor 23 is provided in the piping 25 connecting the liquid drainer 8 and the degassing section 11. Sensor 23 has a measuring unit that measures the amount of generated water discharged from the reactor 2 and flowing into the degassing section 11. The measuring unit of sensor 23 may be an ultrasonic flow meter that measures the flow rate of generated water flowing through the piping 25. The measuring unit of sensor 23 may measure the amount of generated water flowing into the degassing section 11 based on the flow rate of generated water flowing through the piping 25. The data regarding the amount of generated water measured by the measuring unit of sensor 23 is sent to the control unit 21. The measuring unit of sensor 22 may be omitted, or the measuring unit of sensor 23 may be omitted. In the generation system 100, a measuring unit may be provided in either sensor 22 or sensor 23, or a measuring unit may be provided in both sensor 22 and sensor 23.
[0037] Sensor 22 has a detection unit that detects whether the generated water discharged from the liquid drainer 7 contains more than a specified value of bubbles. The specified value may be determined by design, experiment, or simulation. The specified value may be stored in the memory (storage unit) of sensor 22. The detection result detected by the detection unit of sensor 22 is sent to the control unit 21. If the detection unit of sensor 22 detects that the generated water contains more than a specified value of bubbles, the control unit 21 stops the operation of reactors 1 and 2 and liquid drainer 7. If the generated water discharged from liquid drainer 7 contains more than a specified value of bubbles, there is a high possibility that a malfunction has occurred in liquid drainer 7. If the detection unit of sensor 22 detects that the generated water contains more than a specified value of bubbles, stopping the operation of reactors 1 and 2 and liquid drainer 7 makes it possible to repair or replace liquid drainer 7.
[0038] The control unit 21 may output a message indicating that the generated water discharged from the liquid drainer 7 contains more than a specified amount of bubbles. The control unit 21 may also output the message as an attachment to an email or chat message. By checking the message, the user can quickly take action to repair or replace the liquid drainer 7. The control unit 21 may also issue an alarm regarding an abnormality in the liquid drainer 7 by controlling the alarm device. By being aware of the alarm, the user can recognize the abnormality in the liquid drainer 7 and quickly take action to repair or replace the liquid drainer 7.
[0039] Sensor 23 has a detection unit that detects whether the generated water discharged from the liquid drainer 8 contains more than a specified value of bubbles. The detection result detected by the detection unit of sensor 23 is sent to the control unit 21. If the detection unit of sensor 23 detects that the generated water contains more than a specified value of bubbles, the control unit 21 stops the operation of reactors 1 and 2 and liquid drainer 8. If the generated water discharged from liquid drainer 8 contains more than a specified value of bubbles, there is a high possibility that a malfunction has occurred in liquid drainer 8. If the detection unit of sensor 23 detects that the generated water contains more than a specified value of bubbles, stopping the operation of reactors 1 and 2 and liquid drainer 8 makes it possible to repair or replace liquid drainer 8.
[0040] The control unit 21 may output a message indicating that the generated water discharged from the liquid drainer 8 contains more than a specified amount of bubbles. By checking the message, the user can quickly take action to repair or replace the liquid drainer 8. The control unit 21 may also control an alarm to issue an alarm regarding an abnormality in the liquid drainer 8. By being aware of the alarm, the user can recognize the abnormality in the liquid drainer 8 and quickly take action to repair or replace the liquid drainer 8.
[0041] Figure 2 is a diagram showing an example of the mounting position of sensor 22. Sensor 22 is provided in a pipe 24 that connects the liquid drainer 7 and the degassing section 11. Since a part of the pipe 24 is U-shaped, a water seal section is formed in the part of the pipe 24 surrounded by the dotted line in Figure 2. Since the inside of the pipe 24 in the water seal section is filled with generated water, it is preferable to attach the sensor 22 to the side surface of the pipe 24 in the water seal section. For example, since the inside of the pipe 24 above the water seal section may not be filled with generated water, if the sensor 22 is attached to the side surface of the pipe 24 above the water seal section, the sensor 22 may not be able to accurately measure the flow rate of the generated water and may not be able to accurately detect whether the generated water contains bubbles exceeding a specified value. As shown in Figure 2, by attaching the sensor 22 to the side surface of the pipe 24 in the water seal section, the accuracy of measurement and detection of the sensor 22 can be improved. Similarly, by attaching the sensor 23 to the side surface of the pipe 25 in the water seal section, the accuracy of measurement and detection of the sensor 23 can be improved.
[0042] Figure 3 is a diagram showing an example of the degassing section 11. The generated water sent out from the liquid drainers 7 and 8 flows into the degassing section 11. The degassing section 11 removes dissolved gas from the generated water by blowing air into the generated water. The degassing section 11 shown in Figure 3 has a storage tank 31 in which the generated water sent out from the liquid drainers 7 and 8 is stored, and an air supply section 32 that blows air into the generated water stored in the storage tank 31. The generated water sent out from the liquid drainer 7 flows into the storage tank 31 through the pipe 33. The pipe 33 is a part of the pipe that connects the liquid drainer 7 and the degassing section 11. The generated water sent out from the liquid drainer 8 flows into the storage tank 31 through the pipe 34. The pipe 34 is a part of the pipe that connects the liquid drainer 8 and the degassing section 11.
[0043] The control amount for removing dissolved gas in the degassing unit 11 may include the amount of air that the air supply unit 32 blows into the generated water. The control unit 21 determines the amount of air that the air supply unit 32 blows into the generated water based on the amount of generated water flowing into the degassing unit 11. The control unit 21 controls the air supply unit 32 based on the determined amount of air. The control unit 21 may control the amount of air supplied to the air supply unit 32 by inverter control. The control unit 21 may increase the amount of air blown into the generated water if the amount of generated water flowing into the degassing unit 11 is large. The control unit 21 may decrease the amount of air blown into the generated water if the amount of generated water flowing into the degassing unit 11 is small. This makes it possible to increase the amount of air blown into the generated water if the amount of generated water flowing into the degassing unit 11 is large, and decrease the amount of air blown into the generated water if the amount of generated water flowing into the degassing unit 11 is small. The control unit 21 can improve the energy efficiency for removing dissolved gases from the generated water by controlling the degassing unit 11 based on the amount of air corresponding to the amount of generated water flowing into the degassing unit 11.
[0044] The control unit 21 may control the air supply unit 32 so that the amount of air it blows into the generated water increases or decreases in accordance with the increase or decrease in the amount of generated water flowing into the degassing unit 11. If the amount of generated water flowing into the degassing unit 11 increases or decreases linearly, the control unit 21 may control the air supply unit 32 so that the amount of air it blows into the generated water increases or decreases linearly. The amount of dissolved gas in the generated water changes depending on the operating conditions (pressure, temperature, etc.) in reactors 1, 2, gas cooling heat exchangers 5, 6, etc. If the operating conditions in reactors 1, 2, gas cooling heat exchangers 5, 6, etc. are the same, the amount of air the air supply unit 32 blows into the generated water is proportional to the amount of generated water flowing into the degassing unit 11. If the amount of generated water flowing into the degassing unit 11 increases or decreases non-linearly, the control unit 21 may control the air supply unit 32 so that the amount of air it blows into the generated water increases or decreases non-linearly.
[0045] By blowing air into the generated water, the dissolved gas in the generated water is removed, and the air and gas are stored in the storage tank 31. The air and gas in the storage tank 31 are discharged to the atmosphere through the vent pipe (exhaust pipe) 35. The check valve 36 provided in the vent pipe 35 prevents the air and gas from flowing back into the storage tank 31. The generated water in the storage tank 31 is discharged to the outside of the generation system 100 through the pipe 37. The generated water in the storage tank 31 may be temporarily stored in another storage tank. Although not shown in FIG. 3, the storage tank 31 is provided with a level gauge for measuring the liquid level height of the generated water in the storage tank 31 and a drain valve for flowing the generated water in the storage tank 31 into the pipe 37. Further, an overflow pipe for discharging the generated water in the storage tank 31 to the outside may be provided in the storage tank 31 when the liquid level height of the generated water in the storage tank 31 exceeds a predetermined value.
[0046] FIG. 4 is a diagram showing an example of the deaeration unit 11. In the generation system 100, the deaeration unit 11 shown in FIG. 4 may be adopted instead of the deaeration unit 11 shown in FIG. 3. The generated water sent from the liquid drainers 7 and 8 flows into the deaeration unit 11. The deaeration unit 11 removes the dissolved gas from the generated water by heating the generated water. The higher the temperature of the generated water, the lower the solubility of the product gas in the generated water. That is, the higher the temperature of the generated water, the easier it is to remove the dissolved gas from the generated water.
[0047] The degassing unit 11 shown in Figure 4 includes a storage tank 41 where the generated water discharged from liquid drainers 7 and 8 is stored, and a heat exchanger 42 that heats the generated water by performing heat exchange between a heat transfer medium and the generated water. The generated water discharged from liquid drainer 7 flows into the degassing unit 11 through piping 43. The generated water discharged from liquid drainer 8 flows into the degassing unit 11 through piping 44. Pipings 43 and 44 are connected to piping 45. The heat exchanger 42 is connected to piping 45 and 46. The storage tank 41 is connected to piping 46. The generated water discharged from liquid drainer 7 flows into the heat exchanger 42 through piping 43 and 45. The generated water discharged from liquid drainer 8 flows into the heat exchanger 42 through piping 44 and 45. The generated water discharged from the heat exchanger 42 flows into the storage tank 41 through piping 46.
[0048] The heat exchanger 42 is connected to pipes 51 and 52. The heat transfer medium circulating within the generation system 100 passes through pipes 51 and 52. Pipes 51 and 52 may be provided in the circulation path 102, or in another circulation path different from the circulation path 102. The other circulation path may be provided with pipes and valves through which the heat transfer medium flows. The other circulation path may be provided with heaters (heaters) for heating the heat transfer medium flowing through the pipes. Pipes 51 and 52 may be part of the piping connecting reactor 1 and reactor 2. In this case, the heat transfer medium that has passed through reactor 1 flows into the heat exchanger 42 through pipe 51. Pipes 51 and 52 may be part of the piping connecting reactor 2 and pump 13. In this case, the heat transfer medium that has passed through reactor 2 flows into the heat exchanger 42 through pipe 51. After passing through the heat exchanger 42, the heat transfer medium passes through pipe 52.
[0049] The control amount for removing dissolved gas in the degassing unit 11 may include the amount of heat required to heat the generated water. The control unit 21 determines the amount of heat required to heat the generated water based on the amount of generated water flowing into the degassing unit 11. The control unit 21 may also determine the amount of heat required to raise the temperature of the generated water flowing into the storage tank 41 to a predetermined temperature related to the generated water, based on the amount of generated water flowing into the degassing unit 11. The predetermined temperature related to the generated water may be 60°C or higher and 80°C or lower. The predetermined temperature related to the generated water may be determined by design, experiment, or simulation. The predetermined temperature related to the generated water may be stored in the memory (storage unit) of the control unit 21. For example, the control unit 21 may calculate the temperature difference (ΔT) between the first temperature and the predetermined temperature related to the generated water, and determine the amount of heat required to heat the generated water by multiplying the specific heat of the generated water, the amount of generated water, and the temperature difference (ΔT). The first temperature may be, for example, room temperature, or the temperature of the generated water measured by the temperature sensor 61.
[0050] The control unit 21 may determine the amount of heat to heat the generated water so that if the amount of generated water flowing into the degassing unit 11 is large, the amount of heat to heat the generated water will be large. The control unit 21 may also determine the amount of heat to heat the generated water so that if the amount of generated water flowing into the degassing unit 11 is small, the amount of heat to heat the generated water will be small. This makes it possible to increase the amount of heat to heat the generated water if the amount of generated water flowing into the degassing unit 11 is large, and decrease the amount of heat to heat the generated water if the amount of generated water flowing into the degassing unit 11 is small. By controlling the degassing unit 11 based on the amount of heat corresponding to the amount of generated water flowing into the degassing unit 11, the control unit 21 can improve the energy efficiency for removing dissolved gases from the generated water.
[0051] A temperature sensor 61 is installed in the piping 45. The temperature sensor 61 measures the temperature of the generated water before it flows into the heat exchanger 42. The data regarding the temperature of the generated water measured by the temperature sensor 61 is sent to the control unit 21. A temperature sensor 62 is installed in the piping 51. The temperature sensor 62 measures the temperature of the heat transfer medium flowing into the degassing section 11. The data regarding the temperature of the heat transfer medium measured by the temperature sensor 62 is sent to the control unit 21. The control unit 21 controls the amount of heat transfer medium flowing into the heat exchanger 42 based on the determined heat quantity and the temperature of the heat transfer medium flowing into the degassing section 11. The control unit 21 may also control the amount of heat transfer medium flowing into the heat exchanger 42 based on a map or relational expression that shows the relationship between the heat quantity for heating the generated water, the temperature of the heat transfer medium flowing into the degassing section 11, and the amount of heat transfer medium flowing into the heat exchanger 42. The map and relational expression may be obtained by design, experiment, or simulation. The map and relational expressions may be stored in the memory (storage unit) of the control unit 21.
[0052] Piping 53 is connected to pipes 51 and 52. A control valve 54 is provided in pipe 51. A control valve 55 is provided in pipe 53. The control unit 21 controls the amount of heat transfer medium flowing into the heat exchanger 42 by controlling the opening of control valves 54 and 55. The control unit 21 may control the opening of control valves 54 and 55 so that if the amount of generated water flowing into the degassing section 11 is large, the amount of heat transfer medium flowing into the heat exchanger 42 will increase. The control unit 21 may also control the opening of control valves 54 and 55 so that if the amount of generated water flowing into the degassing section 11 is small, the amount of heat transfer medium flowing into the heat exchanger 42 will decrease. In this way, if the amount of generated water flowing into the degassing section 11 is large, the amount of heat transfer medium flowing into the heat exchanger 42 will increase, and if the amount of generated water flowing into the degassing section 11 is small, the amount of heat transfer medium flowing into the heat exchanger 42 will decrease.
[0053] The control unit 21 may control the opening of the control valve 54 and the control valve 55 so that the amount of heat transfer medium flowing into the heat exchanger 42 increases or decreases in accordance with the increase or decrease in the amount of generated water flowing into the degassing unit 11. If the amount of generated water flowing into the degassing unit 11 increases or decreases linearly, the control unit 21 may control the opening of the control valve 54 and the control valve 55 so that the amount of heat transfer medium flowing into the heat exchanger 42 increases or decreases linearly. If the amount of generated water flowing into the degassing unit 11 increases or decreases non-linearly, the control unit 21 may control the opening of the control valve 54 and the control valve 55 so that the amount of heat transfer medium flowing into the heat exchanger 42 increases or decreases non-linearly.
[0054] The following describes the case where the heat transfer medium that has passed through reactor 1 flows into heat exchanger 42 through piping 51. Reactor 1 is heated by the reaction heat during the generation of the product gas. Therefore, the heat transfer medium flowing into heat exchanger 42 is heated by reactor 1, which acts as a heat source. Heat exchanger 42 heats the generated water by exchanging heat between the heat transfer medium heated by reactor 1 and the generated water.
[0055] The following describes the case where the heat transfer medium that has passed through reactor 2 flows into heat exchanger 42 through piping 51. Reactor 2 is heated by the reaction heat during the generation of the product gas. Therefore, the heat transfer medium flowing into heat exchanger 42 is heated by reactor 2, which acts as a heat source. Heat exchanger 42 heats the generated water by exchanging heat between the heat transfer medium heated by reactor 2 and the generated water.
[0056] By heating the generated water, dissolved gases are removed, and air and gases are stored in the storage tank 41. The air and gases in the storage tank 41 are released into the atmosphere through the vent pipe (exhaust pipe) 56. A check valve 57 provided in the vent pipe 56 prevents air and gases from flowing back into the storage tank 41. The generated water in the storage tank 41 is discharged to the outside of the generation system 100 through the piping 58. The generated water in the storage tank 41 may be temporarily stored in another storage tank. Although not shown in Figure 4, the storage tank 41 is equipped with a level gauge for measuring the liquid level of the generated water in the storage tank 41, and a drain valve for draining the generated water from the storage tank 41 into the piping 58. In addition, an overflow pipe may be provided in the storage tank 41 to discharge the generated water from the storage tank 41 to the outside when the liquid level of the generated water in the storage tank 41 exceeds a predetermined value.
[0057] The degassing unit 11 shown in Figure 4 has a heater 63 and a temperature sensor 64 installed in the piping 51. The heater 63 can heat the heat transfer medium before it flows into the heat exchanger 42. The temperature sensor 64 measures the temperature of the heat transfer medium before it flows into the heat exchanger 42. The data regarding the temperature of the heat transfer medium measured by the temperature sensor 64 is sent to the control unit 21. While the heat transfer medium is passing through the piping 51, the heater 63 may heat the heat transfer medium passing through the piping 51. If the temperature of the heat transfer medium before it flows into the heat exchanger 42 is below a predetermined temperature for the heat transfer medium, the control unit 21 may control the heater 63 so that the heat transfer medium passing through the piping 51 is heated by the heater 63. This improves the reliability of removing dissolved gases from the generated water, even if the temperature of the heat transfer medium before it flows into the heat exchanger 42 is below a predetermined temperature for the heat transfer medium. For example, immediately after the operation of reactors 1 and 2 is started, the temperature of the heat transfer medium flowing into the degassing unit 11 is low. Even if the temperature of the heat transfer medium flowing into the degassing section 11 is low, the heater 63 can be used to heat the heat transfer medium passing through the pipe 51, thereby improving the reliability of removing dissolved gases from the generated water. The predetermined temperature for the heat transfer medium may be determined by design, experiment, or simulation. The predetermined temperature for the heat transfer medium may be stored in a memory or other storage unit of the control unit 21. Furthermore, in the degassing section 11 shown in Figure 4, the heater 63 and temperature sensor 64 may be omitted.
[0058] The degassing unit 11 shown in Figure 4 has a heater 65, temperature sensors 66 and 67, and is installed in the piping 46. The heater 65 is capable of heating the generated water after it has passed through the heat exchanger 42. The temperature sensor 66 is positioned between the heat exchanger 42 and the heater 65. The temperature sensor 67 is positioned between the heater 65 and the storage tank 41. The temperature sensors 66 and 67 measure the temperature of the generated water after it has passed through the heat exchanger 42. The temperature sensor 66 measures the temperature of the generated water before it is heated by the heater 65. The temperature sensor 67 measures the temperature of the generated water after it has been heated by the heater 65. The data regarding the temperature of the heat transfer medium measured by the temperature sensors 66 and 67 is sent to the control unit 21.
[0059] If the temperature of the generated water after passing through the heat exchanger 42 (the temperature of the generated water measured by the temperature sensor 66) is below a first predetermined temperature, the control unit 21 may control the heater 65 and heat the generated water passing through the pipe 46 with the heater 65. The control unit 21 may control the heater 65 until the temperature of the generated water measured by the temperature sensor 67 is above a second predetermined temperature, and heat the generated water passing through the pipe 46 with the heater 65. This improves the reliability of removing dissolved gases from the generated water by heating the generated water passing through the pipe 46 with the heater 65, even if the temperature of the generated water after passing through the heat exchanger 42 is low. The first predetermined temperature and the second predetermined temperature may be determined by design, experiment, or simulation. The first predetermined temperature and the second predetermined temperature may be stored in a memory or other storage unit of the control unit 21. In addition, the installation of the heater 65, temperature sensors 66 and 67 may be omitted in the degassing unit 11 shown in Figure 4.
[0060] Figure 5 shows an example of a degassing unit 11. In the production system 100, the degassing unit 11 shown in Figure 5 may be used instead of the degassing unit 11 shown in Figure 3 or Figure 4. The produced water discharged from the liquid drainers 7 and 8 flows into the degassing unit 11. The degassing unit 11 removes dissolved gas from the produced water by heating it. The higher the temperature of the produced water, the lower the solubility of the product gas in the produced water. In other words, the higher the temperature of the produced water, the easier it is to remove dissolved gas from the produced water.
[0061] The degassing unit 11 shown in Figure 5 has a storage tank 71 in which the generated water discharged from liquid drainers 7 and 8 is stored, and a heater (heater) 72 capable of heating the generated water. The generated water discharged from liquid drainer 7 flows into the degassing unit 11 through piping 81. The generated water discharged from liquid drainer 8 flows into the degassing unit 11 through piping 82. Pipings 81 and 82 are connected to piping 83. The storage tank 71 is connected to piping 83. The generated water discharged from liquid drainer 7 flows into the storage tank 71 through piping 81 and 83. The generated water discharged from liquid drainer 8 flows into the storage tank 71 through piping 82 and 83.
[0062] A heater 72 is installed in the piping 83. The heater 72 is capable of heating the generated water passing through the piping 83. That is, the heater 72 is capable of heating the generated water before it flows into the storage tank 71. Temperature sensors 73 and 74 are installed in the piping 83. Temperature sensor 73 measures the temperature of the generated water before it is heated by the heater 72. Temperature sensor 74 measures the temperature of the generated water after it has been heated by the heater 72. The data regarding the temperature of the generated water measured by temperature sensors 73 and 74 is sent to the control unit 21.
[0063] The control amount for removing dissolved gas in the degassing unit 11 may include the amount of heat required to heat the generated water. The control unit 21 determines the amount of heat required to heat the generated water based on the amount of generated water flowing into the degassing unit 11. The control unit 21 may also determine the amount of heat required to raise the temperature of the generated water flowing into the storage tank 41 to a predetermined temperature related to the generated water, based on the amount of generated water flowing into the degassing unit 11. The predetermined temperature related to the generated water may be 60°C or higher and 80°C or lower. The predetermined temperature related to the generated water may be determined by design, experiment, or simulation. The predetermined temperature related to the generated water may be stored in a memory or other storage unit of the control unit 21. For example, the control unit 21 may calculate the temperature difference (ΔT) between the first temperature and the predetermined temperature related to the generated water, and determine the amount of heat required to heat the generated water by multiplying the specific heat of the generated water, the amount of generated water, and the temperature difference (ΔT). The first temperature may be, for example, room temperature, or the temperature of the generated water measured by the temperature sensor 73.
[0064] The control unit 21 may determine the amount of heat to heat the generated water so that if the amount of generated water flowing into the degassing unit 11 is large, the amount of heat to heat the generated water will be large. The control unit 21 may also determine the amount of heat to heat the generated water so that if the amount of generated water flowing into the degassing unit 11 is small, the amount of heat to heat the generated water will be small. This makes it possible to increase the amount of heat to heat the generated water if the amount of generated water flowing into the degassing unit 11 is large, and decrease the amount of heat to heat the generated water if the amount of generated water flowing into the degassing unit 11 is small. By controlling the degassing unit 11 based on the amount of heat corresponding to the amount of generated water flowing into the degassing unit 11, the control unit 21 can improve the energy efficiency for removing dissolved gases from the generated water.
[0065] The control unit 21 controls the drive amount (heating amount) of the heater 72 based on the determined heat quantity. The control unit 21 may also control the drive amount of the heater 72 based on a map or relational expression that shows the relationship between the heat quantity for heating the generated water and the drive amount of the heater 72. The map and relational expression may be obtained by design, experiment, or simulation. The map and relational expression may be stored in the memory (storage unit) of the control unit 21.
[0066] The control unit 21 may control the heater 72 so that the amount of drive of the heater 72 increases or decreases in accordance with the increase or decrease in the amount of generated water flowing into the degassing unit 11. If the amount of generated water flowing into the degassing unit 11 increases or decreases linearly, the control unit 21 may control the heater 72 so that the amount of drive of the heater 72 increases or decreases linearly. If the amount of generated water flowing into the degassing unit 11 increases or decreases non-linearly, the control unit 21 may control the heater 72 so that the amount of drive of the heater 72 increases or decreases non-linearly.
[0067] By heating the generated water, dissolved gases are removed, and air and gas are stored in the storage tank 71. The air and gas in the storage tank 71 are released into the atmosphere through the vent pipe (exhaust pipe) 91. A check valve 92 provided in the vent pipe 91 prevents air and gas from flowing back into the storage tank 71. The generated water in the storage tank 71 is discharged to the outside of the generation system 100 through the piping 93. The generated water in the storage tank 71 may be temporarily stored in another storage tank. Although not shown in Figure 5, the storage tank 71 is equipped with a level gauge for measuring the liquid level of the generated water in the storage tank 71, and a drain valve for draining the generated water from the storage tank 71 into the piping 93. In addition, an overflow pipe may be provided in the storage tank 71 to discharge the generated water from the storage tank 71 to the outside when the liquid level of the generated water in the storage tank 71 exceeds a predetermined value.
[0068] For example, one possible method is to measure the concentration of the generated water or gas after diluting the generated water in a degasser (diluter) and control the amount of diluting air accordingly. However, this control method may have poor responsiveness. Another possible method is to measure the amount and concentration of the generated gas immediately after the reactor outlet and calculate the amount of generated water. However, with this calculation method, the accuracy of calculating the amount of generated water may be low depending on how well the cooling and condensation processes after the reactor outlet function.
[0069] The present invention can also be understood as an operating method or generation method in which a generation system or generation apparatus performs at least a part of the above process. Each of the above configurations and processes can be combined with each other to constitute the present invention, provided that no technical inconsistencies arise.
[0070] 1, 2... Reactors; 3, 4... Economizers; 5, 6... Heat exchangers for gas cooling; 7, 8... Liquid drainers; 9... Raw material gas supply section; 10... Storage tank; 11... Degassing section; 12, 63, 65, 72... Heaters; 13... Pumps; 14... Heat exchangers for heat transfer medium; 15... Cooling towers; 16... Cooling water circulation pumps; 17, 18... Control valves; 19... Chillers; 21... Control section; 22, 23... Sensors; 24, 25 33, 34, 37, 43, 44, 45, 46, 51, 52, 53, 58, 81, 82, 83, 93... Piping; 31, 41, 71... Storage tank; 32... Air supply section; 35, 56, 91... Vent pipe; 36, 57, 92... Check valve; 42... Heat exchanger; 54, 55... Control valve; 61, 62, 64, 66, 67, 73, 74... Temperature sensor; 100... Generation system; 101... Gas path; 102... Circulation path
Claims
1. A production system comprising: a production unit that produces product gas and generated water by a catalytic reaction of a raw material gas and delivers the product gas and the generated water; a degassing unit that removes dissolved gases from the generated water delivered from the production unit; a measuring unit that measures the amount of generated water flowing into the degassing unit; and a control unit that determines a control amount for the removal of dissolved gas in the degassing unit based on the amount of generated water flowing into the degassing unit and controls the degassing unit based on the control amount.
2. The degassing unit removes the dissolved gas from the generated water by blowing air into the generated water, and the control amount includes the amount of air blown into the generated water, the generation system according to claim 1.
3. The degassing unit removes the dissolved gas from the generated water by heating the generated water, and the control amount includes the amount of heat for heating the generated water, according to claim 1.
4. The production system according to claim 3, wherein the degassing unit has a heat exchanger that heats the produced water by performing heat exchange between a heat medium heated by a heat source and the produced water.
5. The generation system according to claim 4, wherein if the temperature of the heat transfer medium before it flows into the heat exchanger is below a predetermined temperature, the heat transfer medium is heated by a heater.
6. The generation system according to claim 4, wherein the heat source is the generation unit which is heated by the reaction heat during the generation of the product gas.
7. A production system according to any one of claims 1 to 6, comprising: a condenser that condenses and liquefies the produced water discharged from the production unit; a separation unit that separates the produced water liquefied by the condenser from the product gas and discharges the produced water; and a detection unit that detects whether the produced water discharged from the separation unit contains more than a specified value of bubbles, wherein the produced water discharged from the separation unit flows into the deaeration unit, and the control unit stops the operation of the production unit and the separation unit when the detection unit detects that the produced water contains more than the specified value of bubbles.
8. A method for operating a production system comprising: a production unit that produces product gas and generated water by a catalytic reaction of a raw material gas and delivers the product gas and the generated water; and a degassing unit that removes dissolved gases dissolved in the generated water delivered from the production unit, the method comprising: measuring the amount of generated water flowing into the degassing unit; determining a control amount for the removal of dissolved gases in the degassing unit based on the amount of generated water flowing into the degassing unit; and controlling the degassing unit based on the control amount.