JP6158149B2 - Distillation equipment - Google Patents

Description

  The present invention relates to a distillation apparatus.

  Conventionally, a distillation apparatus using a distillation process is known. For example, the following Patent Document 1 discloses a distillation apparatus including a distillation column, a distillation condenser, a distillation reboiler, and a reflux pipe for returning the first output fluid flowing out from the distillation condenser to the distillation tower. Has been. The distillation column separates an input fluid containing methanol and hydrous ethanol into a first output fluid containing methanol and a second output fluid containing hydrous ethanol. The distillation condenser cools the first output fluid separated in the distillation column. The distillation reboiler heats the second output fluid separated in the distillation tower. A first output fluid (hereinafter referred to as “reflux fluid”) that has flowed out of the distillation condenser into the reflux pipe is returned to the distillation column through the reflux pipe. In the distillation column, methanol is again separated from the reflux fluid. Thereby, the purity of methanol contained in the first output fluid flowing out from the distillation column is increased. The reflux pipe is connected to the distillation column so that the reflux fluid is returned to a predetermined temperature range of the distillation column (a temperature range in which methanol is effectively separated from the reflux fluid).

  The distillation apparatus further includes a heat pump that supplies the distillation reboiler with the heat received by the working medium (water) in the distillation condenser. The heat pump connects the distillation condenser and the distillation reboiler and circulates the circulation path of the working medium, the compressor that compresses the working medium after evaporation in the distillation condenser, and the operation after the heat is applied by the distillation reboiler. And a pressure reducing valve that decompresses (expands) the medium. In this distillation apparatus, the thermal energy of the first output fluid flowing out from the top of the distillation column is effectively recovered in the distillation reboiler by the heat pump. That is, by effectively using the thermal energy of the first output fluid, reduction of heat energy (energy saving) required for heating the second output fluid in the distillation reboiler is achieved.

Japanese Patent Publication No. 06-009641

  In the distillation apparatus described in Patent Document 1, it is difficult to control the temperature of the reflux fluid flowing out from the distillation condenser. For example, when the temperature of the reflux fluid needs to be lowered to a predetermined temperature, the amount of heat that the working medium receives from the first output fluid in the distillation condenser by increasing the flow rate of the working medium (cooling of the first output fluid in the distillation condenser) It is conceivable to reduce the temperature of the reflux fluid by increasing the amount. In this case, in order to increase the flow rate of the working medium, it is necessary to increase the rotation speed of the compressor and increase the opening of the pressure reducing valve. However, since this operation causes a time lag until the amount of heat actually received by the working medium in the distillation condenser increases, the response is poor. For this reason, since the flow rate of the reflux fluid flowing into the distillation column increases in a state where the temperature of the reflux fluid does not decrease to the predetermined temperature, there is a concern that the distillation accuracy in the distillation column may be reduced.

  An object of the present invention is to provide a distillation apparatus that can effectively recover the thermal energy of the first output fluid and can adjust the temperature of the reflux fluid with high responsiveness.

  As means for solving the problems, the present invention separates an input fluid containing a first component and a second component into a first output fluid containing the first component and a second output fluid containing the second component. A separator for cooling the first output fluid flowing out from the separator, a heater for heating the second output fluid flowing out from the separator, and the condenser and the heater are connected to each other A circulating flow path for circulating the working medium, and a compressor for compressing the working medium after receiving heat energy from the first output fluid by exchanging heat with the first output fluid by the condenser And an expansion mechanism for expanding the working medium after giving the thermal energy to the second output fluid by exchanging heat with the second output fluid by the heater, and the first output flowing out from the condenser Fluid separator A distillation comprising: a reflux channel for returning; and a cooler provided in the reflux channel and configured to cool the reflux fluid that is the first output fluid that has flowed out of the condenser into the reflux channel. Providing equipment.

  In the present invention, the heat energy of the first output fluid can be effectively recovered in the heater via the working medium, and the recirculation flow path is provided with a cooler, so that the recirculation flowing into the separator The temperature of the fluid can be adjusted with high responsiveness. Specifically, since the cooler is provided in the reflux channel, the reflux fluid flowing out from the condenser to the reflux channel is cooled by the cooler before flowing into the separator through the reflux channel. For this reason, compared with the case where the cooling amount of the first output fluid in the condenser is increased by increasing the rotation speed of the compressor and adjusting the expansion amount (decompression amount) in the expansion mechanism, Responsiveness of temperature adjustment increases. Furthermore, since fluctuations in the rotational speed of the compressor are suppressed as compared with the case where the operation is performed, an increase in power necessary for driving the compressor due to the fluctuations is suppressed.

  In this case, the cooling device further includes an inflow amount control unit that controls an inflow amount of the cooling medium for cooling the reflux fluid to the cooler, and the inflow amount control unit flows into the separator. It is preferable to adjust the amount of the cooling medium flowing into the cooler so that the temperature of the reflux fluid falls within a specific range.

  In this way, the temperature of the reflux fluid flowing into the separator is approximately within a specific range, so that the first component is appropriately separated from the reflux fluid in the separator. Therefore, the purity of the first component contained in the first output fluid flowing out from the separator is increased.

  Further, in the present invention, a compressor control unit that controls a rotation speed of the compressor is further provided, and the compressor control unit is configured to include a temperature of the first output fluid flowing into the condenser and a return flow path. It is preferable to adjust the number of rotations of the compressor based on a temperature difference from the temperature of the reflux fluid flowing through the portion between the condenser and the cooler.

  In this aspect, the amount of the reflux fluid that has flowed out of the condenser can be set to a temperature that is slightly lower than the saturation temperature (the condenser can exchange only the latent heat with the first output fluid. By adjusting the rotational speed of the compressor so that the amount of working medium flows into the condenser, it is possible to effectively recover the thermal energy in the condenser while reducing the power required to drive the compressor. Become.

  Further, in the present invention, it further includes an extraction channel that branches off from the reflux channel and extracts a part of the reflux fluid to the outside, and the extraction channel includes the condensation channel in the reflux channel. It is preferable to branch off from a portion between the cooler and the cooler.

  In this way, it is only necessary to cool the remainder of the reflux fluid that has flowed out of the condenser after being removed from the extraction flow path (the amount that returns to the separator) with the cooler. Is reduced.

  In this case, it further comprises a withdrawal amount control unit that adjusts a partial flow rate of the reflux fluid that has flowed out of the condenser to the reflux channel into the withdrawal channel, and the withdrawal amount control unit includes: The flow rate of the reflux fluid that flows through a portion downstream of the connection portion between the return flow channel and the extraction flow channel in the return flow channel, and the portion of the return flow channel that is upstream from the connection portion. The recirculation ratio represented by a value obtained by dividing the flow rate of the recirculation fluid flowing through the flow rate by subtracting the flow rate of the recirculation fluid flowing through the downstream portion of the connection from the flow rate is within the reference range. It is preferable to adjust the flow rate.

  In this way, since the reflux ratio is substantially within the reference range, even if the flow rate of the first output fluid flowing out from the separator varies, the first component contained in the first output fluid The purity of is kept almost constant.

  Further, in the present invention, it further includes a start-up control unit that drives the compressor when the flow rate of the first output fluid flowing into the condenser becomes larger than a preset start-up reference value. preferable.

  In this way, when the flow rate of the first output fluid becomes larger than the startup reference value (the amount of heat energy that can be given from the first output fluid to the second output fluid via the working medium is sufficient). The circuit for automatically recovering the thermal energy of the first output fluid is activated (started up). Therefore, it is possible to more effectively recover the thermal energy of the first output fluid while avoiding unnecessary driving of the compressor.

  In this case, the circuit further includes a start-up control valve provided in a portion of the circulation channel between the condenser and the compressor, and the start-up control unit is configured to supply the first flow into the condenser. When the flow rate of the output fluid becomes larger than the start-up reference value and the pressure of the part of the circulation channel between the condenser and the start-up control valve exceeds the start value, the start-up It is preferable to open the control valve and drive the compressor.

  In this way, the compressor is driven when the pressure in the portion of the circulation channel between the condenser and the start-up control valve exceeds the starting value (pressure at which the compressor can be driven stably). Therefore, the circuit starts up stably and automatically.

  Furthermore, in this case, provided in the parallel flow path, the parallel flow path connected to the circulation flow path so as to be parallel to the portion of the circulation flow path through which the liquid working medium flows, A pump that sends a liquid working medium to the condenser, and the start-up control unit drives the pump until a storage amount of the liquid working medium in the condenser reaches a preset reference amount. It is preferable to do.

  If it does in this way, the quantity of the liquid working medium which will be evaporated by receiving heat energy from the first output fluid in the condenser, that is, will be accumulated between the condenser and the start-up control valve after evaporating in the condenser. The liquid working medium in the parallel flow path and the circulation flow path is sent to the condenser by the pump until a sufficient amount of the gaseous working medium is secured. Therefore, the circuit can be started up earlier.

  Moreover, in this invention, it is preferable to further provide the stop control part which stops the said compressor when the flow volume of said 1st output fluid which flows in into the said condenser becomes smaller than a stop reference value.

  In this way, when the flow rate of the first output fluid flowing into the condenser is smaller than the stop reference value (thermal energy that can be given from the first output fluid to the second output fluid via the working medium). The compressor is automatically stopped when a sufficient amount of the gas cannot be secured), so that damage to the compressor can be avoided.

  In the present invention, it is preferable that the heater has a heating medium flow path through which a heating medium for heating the second output fluid flows.

  In this way, even if the heating amount of the second output fluid in the heater is insufficient with only the amount of heat input to the heater through the working medium, the heating medium is supplied to the heater from the outside. By doing so, the shortage can be compensated.

  In the present invention, it is preferable that the condenser has a cooling medium flow path through which a cooling medium for cooling the first output fluid flows.

  In this way, even if the amount of cooling of the first output fluid in the condenser is insufficient by only the amount of heat recovered by the condenser via the working medium, the cooling medium is supplied to the condenser from the outside. By doing so, the shortage can be compensated.

  As described above, according to the present invention, it is possible to provide a distillation apparatus that can effectively recover the thermal energy of the first output fluid and can adjust the temperature of the reflux fluid with high responsiveness.

It is a figure which shows the outline of a structure of the distillation apparatus of one Embodiment of this invention. It is a flowchart which shows the control content of the control part at the time of the steady operation of the distillation apparatus of FIG. It is a flowchart which shows the control content of the control part at the time of starting of the heat recovery circuit of the distillation apparatus of FIG. It is a flowchart which shows the control content of the control part at the time of the stop of the heat recovery circuit of the distillation apparatus of FIG.

  A distillation apparatus according to an embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the distillation apparatus includes a separator 22, a condenser 24 that cools the first output fluid flowing out from the separator 22, and a heater that heats the second output fluid flowing out from the separator 22. 26, a reflux channel 13 for returning the first output fluid (hereinafter referred to as “reflux fluid”) flowing out of the condenser 24 to the separator 22, a cooler 28 provided in the reflux channel 13, It includes a heat recovery circuit 30 that supplies thermal energy recovered from the first output fluid to the second output fluid via the working medium, and a control unit 50 that performs various controls.

  The separator 22 separates an input fluid including a first component and a second component different from the first component into a first output fluid including the first component and a second output fluid including the second component. For example, the first output fluid is a distillate vapor (distillate) containing many low boiling (highly volatile) components as the first component, and the second output fluid is the first component as the second component. This is a bottomed liquid containing a large amount of components having a boiling point higher than that of the first component (having volatility lower than that of the first component). The input fluid flows into the separator 22 through the input flow path 11. The first output fluid flows into the condenser 24 through the output channel 12, and the second output fluid flows into the heater 26 through the output channel 16.

  The condenser 24 cools the first output fluid by exchanging heat between the first output fluid and the working medium of the heat recovery circuit 30. In the present embodiment, the condenser 24 is configured so that the first output fluid can be cooled also by a cooling medium (cooling water or the like) supplied from an external cooling source (not shown). Specifically, the condenser 24 has a cooling medium flow path 25 through which a cooling medium supplied from a cooling source flows. The cooling medium flow path 25 is provided with a cooling medium amount adjusting valve V2 whose opening degree can be adjusted. The cooling medium channel 25 may be omitted.

  The first output fluid condensed by exchanging heat with the working medium or the cooling medium in the condenser 24 flows out to the reflux passage 13 as a reflux fluid. In the present embodiment, the extraction channel 14 is branched from the reflux channel 13. The extraction channel 14 is a channel for extracting a part of the reflux fluid to the outside. For this reason, a part of the reflux fluid that has flowed out of the condenser 24 to the reflux channel 13 is extracted to the outside through the extraction channel 14, and the remainder of the reflux fluid is left above the separator 22 (first from the reflux fluid). Temperature region) where the components are effectively separated.

  The heater 26 heats the second output fluid by exchanging heat between the second output fluid and the working medium of the heat recovery circuit 30. In the present embodiment, the heater 26 is configured so that the second output fluid can also be heated by a heating medium (steam or the like) supplied from an external heat source (not shown). Specifically, the heater 26 has a heating medium flow path 27 through which a heating medium supplied from a heat source flows. The heating medium flow path 27 is provided with a heating medium amount adjusting valve V3 whose opening degree can be adjusted. The heating medium flow path 27 may be omitted.

  Part of the second output fluid that has flowed into the heater 26 is extracted to the outside through the extraction flow path 18, and the remainder of the second output fluid is heat-exchanged with the working medium or the heating medium by the heater 26. And then returned to the lower part of the separator 22 through the return channel 17.

  The cooler 28 is provided in the reflux channel 13. More specifically, the cooler 28 is provided in a portion of the reflux channel 13 on the downstream side of the connection portion between the reflux channel 13 and the extraction channel 14. The cooler 28 cools the reflux fluid by exchanging heat between the reflux fluid and a cooling medium (cooling water or the like) supplied from an external cooling source. Specifically, the cooler 28 has a cooling medium flow path 29 through which a cooling medium supplied from a cooling source flows. The cooling medium flow path 29 is provided with a cooling medium amount adjusting valve V1 whose opening degree can be adjusted.

  The reflux fluid that has flowed out of the condenser 24 into the reflux channel 13 is cooled to a predetermined temperature range by the cooler 28 (a temperature range in which the first component is effectively separated from the reflux fluid by the separator 22), and then the separator. 22 flows in.

  The heat recovery circuit 30 converts the heat energy received by the working medium from the first output fluid by heat exchange between the first output fluid and the working medium in the condenser 24 into the working medium and the second output fluid in the heater 26. This is a circuit to be given to the second output fluid by heat exchange with. That is, the heat recovery circuit 30 functions as a so-called heat pump that transfers heat from the relatively low temperature first output fluid to the relatively high temperature second output fluid via the working medium. Specifically, the heat recovery circuit 30 includes a circulation channel 32 through which the working medium circulates, a compressor 34 that compresses the working medium, and an expansion mechanism 36 that expands the working medium.

  The circulation flow path 32 connects the condenser 24, the compressor 34, the heater 26, and the expansion mechanism 36 in this order in series. A start-up control valve V <b> 5 is provided at a portion between the condenser 24 and the compressor 34 in the circulation flow path 32.

  The compressor 34 is provided in the circulation channel 32 at a site downstream of the condenser 24 and upstream of the heater 26. The compressor 34 raises the temperature by compressing the gaseous working medium flowing out of the condenser 24. The gaseous working medium that has flowed out of the compressor 34 flows into the heater 26 and becomes liquid by exchanging heat with the second output fluid in the heater 26.

  The expansion mechanism 36 is provided in the circulation channel 32 at a site downstream of the heater 26 and upstream of the condenser 24. The expansion mechanism 36 decompresses the liquid working medium flowing out of the heater 26 by expanding it. The working medium that has flowed out of the expansion mechanism 36 flows into the condenser 24 and becomes gaseous by exchanging heat with the first output fluid in the condenser 24.

  In the present embodiment, the heat recovery circuit 30 further includes a parallel flow path 37 connected to the circulation flow path 32, a pump 38 provided in the parallel flow path 37, and an on-off valve V6.

  The parallel flow path 37 is connected to the circulation flow path 32 so as to be parallel to the portion of the circulation flow path 32 through which the liquid working medium flows. Specifically, the parallel flow path 37 is connected to the circulation flow path 32 so as to be parallel to a portion of the circulation flow path 32 between the heater 26 and the expansion mechanism 36.

  The pump 38 sends the liquid working medium to the condenser 24.

  The on-off valve V6 is located downstream of the portion of the circulation passage 32 that is in parallel with the pump 38 (the portion of the circulation passage 32 that connects the circulation passage 32 and the upstream end of the parallel passage 37). It is provided at a portion upstream of the connection portion between the circulation channel 32 and the downstream end of the parallel channel 37. The on-off valve V6 is closed during the operation of the pump 38. The on-off valve V6 may be a check valve that allows the working medium to pass in the direction from the heater 26 toward the expansion mechanism 36 while restricting the passage in the reverse direction.

  The control unit 50 includes an inflow amount control unit 51, a compressor control unit 52, a withdrawal amount control unit 53, a start-up control unit 54, and a stop control unit 55.

  The inflow amount control unit 51 adjusts the inflow amount of the cooling medium to the cooler 28 so that the temperature of the reflux fluid flowing into the separator 22 falls within a specific range. Specifically, the inflow amount control unit 51 is configured so that the detection value T1 of the temperature sensor 41 provided in the portion between the cooler 28 and the separator 22 in the reflux flow path 13 is within a specific range. The opening degree of the cooling medium amount adjusting valve V1 is adjusted. More preferably, the inflow amount control unit 51 adjusts the opening degree of the cooling medium amount adjusting valve V1 so that the detected value T1 becomes the designated recirculation temperature Tr.

  The compressor controller 52 adjusts the rotation speed of the compressor 34 based on the temperature difference between the temperature of the first output fluid flowing into the condenser 24 and the temperature of the reflux fluid flowing out of the condenser 24 into the reflux passage 13. To do. Specifically, the compressor control unit 52 determines the temperature provided at a portion between the condenser 24 and the cooler 28 in the reflux flow path 13 from the detection value T2 of the temperature sensor 42 provided in the output flow path 12. The rotational speed of the compressor 34 is adjusted so that the temperature difference ΔT obtained by subtracting the detection value T3 of the sensor 43 becomes the specified value α. The specified value α is preferably set to an arbitrary temperature higher than 0 ° C. and 5 ° C. or lower. In other words, the specified value α is preferably set to a value at which the first output fluid exchanges substantially only latent heat with the working medium in the condenser 24. That is, the compressor control unit 52 adjusts the rotation speed of the compressor 34 so that the first output fluid flowing into the condenser 24 in a gaseous state flows out of the condenser 24 in a liquid state having a temperature slightly lower than the saturation temperature. adjust.

  The withdrawal amount control unit 53 adjusts the opening degree of the withdrawal amount adjustment valve V4 so that the reflux ratio R is within the reference range. The recirculation ratio R is determined by the detection value Q1 of the flow rate sensor 44 provided at the upstream side of the connection portion between the recirculation flow path 13 and the extraction flow path 14 in the recirculation flow path 13 and the recirculation flow path 13. Of these, it is calculated based on the detection value Q2 of the flow rate sensor 45 provided in the downstream portion of the connection portion. Specifically, the reflux ratio R is represented by a value (Q2 / (Q1-Q2)) obtained by dividing the detected value Q2 by a flow rate difference (Q1-Q2) obtained by subtracting the detected value Q2 from the detected value Q1. In the present embodiment, the withdrawal amount control unit 53 adjusts the opening degree of the withdrawal amount adjustment valve V4 so that the reflux ratio R becomes the designated reflux ratio R0.

  The startup control unit 54 performs various controls when the heat recovery circuit 30 is started up (at startup). The start-up control unit 54 drives the compressor 34 when the flow rate of the first output fluid flowing out from the separator 22 becomes larger than a preset start-up reference value Q0. That is, when the flow rate of the first output fluid is equal to or less than the startup reference value Q0, the start of the compressor 34 is prohibited. In the present embodiment, the flow rate of the first output fluid flowing out from the separator 22 is detected by the flow rate sensor 44. The startup reference value Q0 is set to the flow rate of the first output fluid that can sufficiently secure the amount of thermal energy that can be given from the first output fluid to the second output fluid via the working medium. In the present embodiment, the start-up control unit 54 has the detection value Q1 of the flow sensor 44 larger than the start-up reference value Q0, and between the condenser 24 and the start-up control valve V5 in the circulation channel 32. When the detected value P1 of the pressure sensor 33 provided in the part exceeds the operating value P0, the start-up control valve V5 is opened and the compressor 34 is driven. Further, the start-up control unit 54 closes the on-off valve V6 and drives the pump 38 until the storage amount of the liquid working medium in the condenser 24 reaches a preset reference amount L0. The storage amount of the liquid working medium in the condenser 24 is detected by a liquid level sensor 40 provided in the condenser 24. The reference amount L0 is accumulated as a gaseous working medium between the condenser 24 and the start-up control valve V5 after the liquid working medium in the condenser 24 evaporates by receiving thermal energy from the first output fluid. Sometimes, the detected value P1 of the pressure sensor 33 is set to an amount that can be set to the operating value P0 or more.

  The stop control unit 55 performs various controls when the heat recovery circuit 30 is stopped. The stop control unit 55 stops the compressor 34 when the flow rate of the first output fluid flowing out from the separator 22 (detected value Q1 of the flow rate sensor 44) becomes smaller than the stop reference value. In the present embodiment, the stop reference value is set to the same value as the startup reference value Q0.

  Hereinafter, specific control contents of the control unit 50 will be described with reference to FIGS. FIG. 2 shows the control content during steady operation, FIG. 3 shows the control content when the heat recovery circuit 30 is started up, and FIG. 4 shows the control content when the heat recovery circuit 30 is stopped. .

  First, the control contents of the control unit 50 during steady operation will be described with reference to FIG.

  The controller 50 determines whether or not the temperature difference ΔT obtained by subtracting the detection value T3 of the temperature sensor 43 from the detection value T2 of the temperature sensor 42 is larger than the specified value α (step ST11).

  As a result, when the temperature difference ΔT is larger than the specified value α (YES in step ST11), that is, when the cooling amount of the first output fluid by the working medium is too large, the control unit 50 operates the working medium to the condenser 24. In order to reduce the inflow amount of the compressor 34, the rotational speed of the compressor 34 is lowered (step ST12). On the other hand, when the temperature difference ΔT is equal to or less than the specified value α (NO in step ST11), the control unit 50 determines whether or not the temperature difference ΔT is smaller than the specified value α (step ST13).

  As a result, when the temperature difference ΔT is smaller than the specified value α (YES in step ST13), that is, when the cooling amount of the first output fluid by the working medium is too small, the control unit 50 operates the working medium to the condenser 24. In order to increase the inflow amount of the compressor 34, the rotational speed of the compressor 34 is increased (step ST14).

  Then, after step ST12 or step ST14, the controller 50 determines whether or not the temperature difference ΔT is equal to the specified value α (step ST15). As a result, if the temperature difference ΔT is not equal to the specified value α (NO in step ST15), the process returns to step ST11. On the other hand, when temperature difference ΔT is equal to specified value α (YES in step ST15) and NO in step ST13 (when temperature difference ΔT is equal to specified value α), control unit 50 detects temperature sensor 41. It is determined whether or not the value T1 is higher than the designated reflux temperature Tr (step ST16).

  As a result, when the detected value T1 is larger than the designated reflux temperature Tr (YES in step ST16), the control unit 50 opens the cooling medium amount adjustment valve V1 in order to increase the cooling amount of the reflux fluid in the cooler 28. (Step ST17). On the other hand, when the detected value T1 is equal to or lower than the designated reflux temperature Tr (NO in step ST16), the control unit 50 determines whether or not the detected value T1 is smaller than the designated reflux temperature Tr (step ST18).

  As a result, when the detected value T1 is smaller than the specified reflux temperature Tr (YES in step ST18), the control unit 50 opens the cooling medium amount adjusting valve V1 in order to reduce the cooling amount of the reflux fluid in the cooler 28. (Step ST19).

  Then, after step ST17 or step ST19, the control unit 50 determines whether or not the detection value T1 is equal to the designated reflux temperature Tr (step ST20). As a result, when the detected value T1 is not equal to the designated reflux temperature Tr (NO in step ST20), the process returns to step ST16. On the other hand, when the detected value T1 is equal to the specified reflux temperature Tr (YES in step ST20) and NO in step ST18 (when the detected value T1 is equal to the specified reflux temperature Tr), the control unit 50 controls the flow rate sensor 44. And the detection value Q2 of the flow sensor 45 are read, and the reflux ratio R is calculated based on both detection values (step ST21).

  Next, the control unit 50 determines whether or not the reflux ratio R is larger than the designated reflux ratio R0 (step ST22). As a result, when the reflux ratio R is larger than the designated reflux ratio R0 (YES in step ST22), the control unit 50 increases the amount of reflux fluid extracted from the extraction channel 14 (returns to the separator 22). In order to reduce the flow rate of the reflux medium, the opening degree of the extraction amount adjusting valve V4 is increased (step ST23). On the other hand, when the reflux ratio R is equal to or less than the designated reflux ratio R0 (NO in step ST22), the control unit 50 determines whether or not the reflux ratio R is smaller than the designated reflux ratio R0 (step ST24).

  As a result, when the reflux ratio R is smaller than the designated reflux ratio R0 (YES in step ST24), the control unit 50 reduces the amount of reflux fluid extracted from the extraction flow path 14 (returns to the separator 22). In order to increase the flow rate of the reflux medium, the opening degree of the extraction amount adjusting valve V4 is lowered (step ST25).

Then, after step ST23 or step ST25, the controller 50 determines whether or not the reflux ratio R is equal to the designated reflux ratio R0 (step ST26). As a result, when the reflux ratio R is not equal to the designated reflux ratio R0 (NO in step ST26), the process returns to step ST21.
On the other hand, when the reflux ratio R is equal to the designated reflux ratio R0 (YES in step ST26) and NO in step ST24 (when the reflux ratio R is equal to the designated reflux ratio R0), the control unit 50 controls the heater 26. The flow rate of the heating medium supplied to is determined, and the heating medium amount adjustment valve V3 is opened at the opening degree (step ST27). Then, it returns to step ST11. In this way, the temperature difference ΔT, the detected value T1, and the reflux ratio R are controlled to be constant.

  Next, the control contents of the control unit 50 when starting up (starting up) the heat recovery circuit 30 will be described with reference to FIG. In a state before the heat recovery circuit 30 is started up, the compressor 34 and the pump 38 are stopped, and the start-up control valve V5 is closed. In order to cool the first output fluid in the condenser 24, the cooling medium amount adjusting valve V2 is open.

  In this state, the controller 50 first reads the detection value Q1 of the flow sensor 44 (step ST31), and determines whether or not the detection value Q1 is larger than the starting reference value Q0 (step ST32).

  If the detected value Q1 is equal to or lower than the starting reference value Q0 (NO in step ST32), the process returns to step ST31. On the other hand, when detected value Q1 is larger than startup reference value Q0 (YES in step ST32), control unit 50 closes cooling medium amount adjustment valve V2 (step ST33). The reason why the cooling medium amount adjusting valve V2 is closed is that the first output fluid can be cooled by the liquid working medium in the condenser 24. Then, the detection value L1 of the liquid level sensor 40 is read (step ST34), and it is determined whether or not the detection value L1 is larger than the reference amount L0 (step ST35).

  As a result, when the detected value L1 is equal to or smaller than the reference amount L0 (NO in step ST35), the control unit 50 closes the on-off valve V6 and drives the pump 38 in order to increase the amount of the liquid working medium in the condenser 24. (Step ST36). By closing the on-off valve V6, the working medium discharged from the pump 38 surely flows into the condenser 24. On the other hand, when the detected value L1 is larger than the reference amount L0 (TES in step ST35), the control unit 50 stops the pump 38 and opens the on-off valve V6 (step ST37), and reads the detected value P1 of the pressure sensor 33. (Step ST38). Thereafter, the control unit 50 determines whether or not the detected value P1 is larger than the operating value P0 (step ST39).

  As a result, when the detected value P1 is equal to or less than the operating value P0 (NO in step ST39), the process returns to step ST38. On the other hand, when detected value P1 is larger than operating value P0 (YES in step ST39), control unit 50 opens start-up control valve V5 and drives compressor 34 (step ST40). Thereby, the heat recovery circuit 30 starts up.

  And the control part 50 determines the flow volume of the heating medium supplied to the heater 26, and opens the heating medium amount adjustment valve V3 with the opening degree (step ST41). Then, it moves to step ST11, ie, the flow at the time of steady operation.

  Then, the control content of the control part 50 at the time of the stop of the heat recovery circuit 30 is demonstrated, referring FIG. In FIG. 4, the same content as the control content during the steady operation is denoted by the same reference numerals as the control content during the steady operation.

  During the steady operation, the control unit 50 reads the detection value Q1 of the flow sensor 44 (step ST51), and determines whether or not the detection value Q1 is larger than the stop reference value Q0 (step ST52).

  If the detected value Q1 is larger than the stop reference value Q0 (YES in step ST52), the process returns to step ST31. On the other hand, when detected value Q1 is equal to or smaller than stop reference value Q0 (NO in step ST52), control unit 50 stops compressor 34 (step ST53). Thereby, the heat recovery circuit 30 stops.

  Then, the control part 50 determines the flow volume of the heating medium supplied to the heater 26, and opens the heating medium amount adjustment valve V3 with the opening degree (step ST54). At the same time, the control unit 50 determines the flow rate of the cooling medium supplied to the condenser 24, and opens the cooling medium amount adjusting valve V2 at the opening degree (step ST55).

  Since the control content after this is the same as the control content in steps ST16 to ST26 during steady operation, the description thereof is omitted. However, if NO in step ST24 and YES in step ST26, the process returns to step ST54.

  As described above, in this distillation apparatus, the heat energy of the first output fluid can be effectively recovered in the heater 26 via the working medium, and the cooler 28 is provided in the reflux channel 13. Therefore, the temperature of the reflux fluid flowing into the separator 22 can be adjusted with high responsiveness. Specifically, since the refrigerating channel 13 is provided with the cooler 28, the recirculating fluid that has flowed out of the condenser 24 to the recirculating flow channel 13 flows into the separator 22 through the recirculating flow channel 13 before the cooler 28. Cooled by. For this reason, compared with the case where the cooling amount of the first output fluid in the condenser 24 is increased by performing an operation of increasing the rotation speed of the compressor 34 and adjusting the expansion amount (decompression amount) in the expansion mechanism 36, Responsiveness of temperature adjustment of the reflux fluid is increased. Furthermore, since fluctuations in the rotational speed of the compressor 34 are suppressed as compared with the case of performing the operation, an increase in power necessary for driving the compressor 34 due to the fluctuations is suppressed.

  Further, in the present embodiment, the opening degree of the cooling medium amount adjusting valve V1 is adjusted by the inflow amount control unit 51 so that the detected value T1 of the temperature sensor 41 becomes the designated recirculation temperature Tr. For this reason, since the temperature of the reflux fluid flowing into the separator 22 becomes substantially equal to the designated reflux temperature Tr, the first component is appropriately separated from the reflux fluid in the separator 22. Therefore, the purity of the first component contained in the first output fluid flowing out from the separator 22 is increased.

  Further, in the present embodiment, the rotation speed of the compressor 34 is adjusted by the compressor control unit 52 so that the temperature difference ΔT becomes the specified value α. For this reason, in the condenser 24, the first output fluid and the working medium perform heat exchange with substantially only latent heat. In other words, the first output fluid that has flowed into the condenser 24 in a gaseous state flows out of the condenser 24 in a liquid state having a temperature slightly lower than the saturation temperature. Therefore, it is possible to effectively recover the thermal energy in the condenser 24 while reducing the power required for driving the compressor 34.

  Further, in the present embodiment, the extraction flow path 14 is branched from a portion of the reflux flow path 13 between the condenser 24 and the cooler 28. For this reason, it is sufficient that only the remaining portion (returned to the separator 22) after being extracted from the extraction flow path 14 of the reflux fluid flowing out from the condenser 24 is cooled by the cooler 28. 28 load is reduced.

  Further, in the present embodiment, the opening degree of the extraction amount adjustment valve V4 is adjusted by the extraction amount control unit 53 so that the recirculation ratio R becomes the designated recirculation ratio R0. For this reason, since the reflux ratio R is substantially maintained at the designated reflux ratio R0, even when the flow rate of the first output fluid flowing out from the separator 22 fluctuates, the first output fluid included in the first output fluid is included. The purity of one component is kept almost constant.

  In this embodiment, when the detection value Q1 of the flow sensor 44 is larger than the startup reference value Q0 and the detection value P1 of the pressure sensor 33 exceeds the operating value P0, the startup control unit 54 The raising control valve V5 is opened and the compressor 34 is driven. In other words, a sufficient amount of heat energy can be provided from the first output fluid to the second output fluid via the working medium, and the pressure of the gaseous working medium flowing into the compressor 34 is compressed. When the pressure that can stably drive the machine 34 is exceeded, the start-up control valve V5 is opened and the compressor 34 is driven. Therefore, the heat recovery circuit 30 starts up stably and automatically. Further, since the start-up control valve V5 is closed until the detected value P1 exceeds the operating value P0, the gaseous working medium compressor 34 from the upstream side to the downstream side before the detected value P1 exceeds the operating value P0. And the time for the detection value P1 to reach the operating value P0 due to the leakage is avoided.

  Further, in the present embodiment, the start-up control unit 54 drives the pump 38 until the detection value L1 of the liquid level sensor 40 reaches the reference amount L0. Therefore, the heat recovery circuit 30 starts up earlier.

  In the present embodiment, the compressor 34 is stopped by the stop control unit 55 when the detection value Q1 of the flow sensor 44 becomes smaller than the stop reference value Q0. Therefore, damage to the compressor 34 and the like are avoided.

  In the present embodiment, the heater 26 includes a heating medium flow path 27. For this reason, even if the heating amount of the second output fluid in the heater 26 is insufficient only by the amount of heat input to the heater 26 through the working medium, the heating medium is supplied to the heater 26 from the outside. By doing so, the shortage can be compensated.

  In the present embodiment, the condenser 24 has a cooling medium flow path 25. For this reason, even if only the amount of heat recovered from the condenser 24 via the working medium is insufficient for cooling the first output fluid in the condenser 24, the cooling medium is supplied to the condenser 24 from the outside. By doing so, the shortage can be compensated.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the above-described embodiment, the example in which the inflow amount control unit 51 adjusts the opening degree of the cooling medium amount adjustment valve V1 so that the detection value T1 of the temperature sensor 41 becomes the specified recirculation temperature Tr has been shown. The control unit 51 may adjust the opening of the cooling medium amount adjusting valve V1 so that the detection value T1 falls within a specific range. In this case, when the detected value T1 is smaller than the lower limit value of the specific range, the inflow amount control unit 51 decreases the opening of the cooling medium amount adjusting valve V1, and the detected value T1 is lower than the upper limit value of the specific range. Is larger, the opening degree of the cooling medium amount adjusting valve V1 is increased.

  Moreover, in the said embodiment, although the extraction amount control part 53 showed the example which adjusts the opening degree of the extraction amount adjustment valve V4 so that the recirculation | reflux ratio R may become the designated recirculation | reflux ratio R0, the extraction amount control part was shown. 53 may adjust the opening degree of the extraction amount adjusting valve V4 so that the reflux ratio R falls within the reference range. In this case, when the reflux ratio R is smaller than the lower limit value of the reference range, the withdrawal amount control unit 53 reduces the opening degree of the withdrawal amount adjustment valve V4, and the reflux ratio R is smaller than the upper limit value of the reference range. If larger, the opening degree of the extraction amount adjusting valve V4 is increased.

  Further, in the above embodiment, the example in which the extraction flow path 14 is connected to the upstream side of the cooler 28 in the reflux flow path 13 is shown. Of these, it may be connected to the downstream side of the cooler 28.

  In the above embodiment, the example in which the adjustment of the inflow amount of the cooling medium to the cooler 28 is performed by adjusting the opening degree of the cooling medium amount adjusting valve V1, but the method for adjusting the inflow amount of the cooling medium has been described. Is not limited to this. For example, a pump capable of adjusting the number of rotations may be provided in the cooling medium flow path 29, and the amount of the cooling medium flowing into the cooler 28 may be adjusted by adjusting the number of rotations of the pump.

  Moreover, in the said embodiment, although the example which adjusts the extraction amount of the recirculation | reflux fluid from the extraction flow path 14 by adjusting the opening degree of the extraction amount adjustment valve V4 was shown, adjustment of the said extraction amount is shown. The method is not limited to this. For example, a plurality of pipes may be connected in parallel to the extraction flow path 14, and an opening / closing valve may be provided in these pipes, and the extraction amount may be adjusted by the number of opening each opening / closing valve.

DESCRIPTION OF SYMBOLS 13 Reflux flow path 14 Extraction flow path 22 Separator 24 Condenser 25 Cooling medium flow path 26 Heater 27 Heating medium flow path 28 Cooler 29 Cooling medium flow path 30 Heat recovery circuit 32 Circulation flow path 34 Compressor 36 Expansion mechanism 37 Parallel flow path 38 Pump 40 Liquid level sensor 50 Control unit 51 Inflow control unit 52 Compressor control unit 53 Extraction amount control unit 54 Start-up control unit 55 Stop control unit V1 Cooling medium amount adjustment valve V2 Cooling medium amount adjustment valve V3 Heating medium amount adjustment valve V4 Extraction amount adjustment valve V5 Startup control valve V6 On-off valve

Claims (10)

A separator for separating an input fluid including a first component and a second component into a first output fluid including the first component and a second output fluid including the second component;
A condenser for cooling the first output fluid flowing out of the separator;
A heater for heating the second output fluid flowing out of the separator;
A circulation channel for connecting the condenser and the heater and circulating the working medium;
A compressor that compresses the working medium after receiving heat energy from the first output fluid by exchanging heat with the first output fluid in the condenser;
An expansion mechanism that expands the working medium after giving the thermal energy to the second output fluid by exchanging heat with the second output fluid in the heater;
A reflux flow path for returning the first output fluid flowing out of the condenser to the separator;
A cooler for cooling the reflux fluid that is the first output fluid that is provided in the reflux channel and flows out of the condenser into the reflux channel;
An extraction channel that branches off from the reflux channel and extracts a part of the reflux fluid to the outside ,
The said extraction flow path is a distillation apparatus branched from the site | part between the said condenser and the said cooler among the said reflux flow paths . The distillation apparatus according to claim 1,
An inflow amount control unit for controlling an inflow amount of a cooling medium for cooling the reflux fluid to the cooler in the cooler;
The inflow amount control unit adjusts the inflow amount of the cooling medium to the cooler so that the temperature of the reflux fluid flowing into the separator falls within a specific range. In the distillation apparatus according to claim 1 or 2,
A compressor control unit for controlling the rotation speed of the compressor;
The compressor control unit is configured such that a temperature difference between the temperature of the first output fluid flowing into the condenser and the temperature of the reflux fluid flowing through a portion of the reflux channel between the condenser and the cooler. A distillation apparatus for adjusting the rotational speed of the compressor based on the above. In the distillation apparatus in any one of Claims 1 thru | or 3 ,
An extraction amount control unit for adjusting a partial flow rate of the reflux fluid that has flowed out of the condenser to the reflux channel to the extraction channel;
The extraction amount control unit is configured to determine a flow rate of the reflux fluid that flows through a portion downstream of a connection portion between the reflux channel and the extraction channel in the reflux channel. A recirculation ratio represented by a value obtained by dividing a flow rate of the reflux fluid flowing through the site upstream of the connection part by a flow rate difference obtained by subtracting the flow rate of the reflux fluid flowing through the site downstream of the connection unit is a reference range. A distillation apparatus for adjusting the partial flow rate so as to be contained within the distillation apparatus. The distillation apparatus according to any one of claims 1 to 4 ,
A distillation apparatus further comprising a start-up control unit that drives the compressor when the flow rate of the first output fluid flowing into the condenser becomes larger than a preset start-up reference value. The distillation apparatus according to claim 5 ,
Further comprising a start-up control valve provided in a portion of the circulation channel between the condenser and the compressor;
The start-up control unit is configured such that the flow rate of the first output fluid flowing into the condenser is greater than the start-up reference value, and between the condenser and the start-up control valve in the circulation channel. A distillation apparatus that opens the start-up control valve and drives the compressor when the pressure at the part exceeds the starting value. The distillation apparatus according to claim 6 ,
A parallel flow path connected to the circulation flow path so as to be parallel to a portion of the circulation flow path through which the liquid working medium flows;
A pump that is provided in the parallel flow path and sends the liquid working medium to the condenser;
The start-up control unit is a distillation apparatus that drives the pump until a storage amount of the liquid working medium in the condenser reaches a preset reference amount. The distillation apparatus according to any one of claims 1 to 7 ,
A distillation apparatus further comprising a stop control unit that stops the compressor when a flow rate of the first output fluid flowing into the condenser becomes smaller than a stop reference value. The distillation apparatus according to any one of claims 1 to 8 ,
The said heater has a heating-medium flow path through which the heating medium for heating said 2nd output fluid flows. The distillation apparatus according to any one of claims 1 to 9 ,
The condenser has a cooling medium flow path through which a cooling medium for cooling the first output fluid flows.

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