Distillation apparatus

Abstract

To provide a distillation apparatus capable of obtaining high distillation treatment efficiently while achieving energy saving, decarbonization and CO2 reduction.SOLUTION: The distillation apparatus 1 comprises a heat pump type steam generating part 20 for generating heated steam by heating reboiler drain water as drain water of a reboiler circulation water for heating a reboiler 13 by a heat source of condenser drain water as drain water of a column bottom part 11 and taking out a low boiling point component from a column top part 12 as a distillate and taking out a high boiling point component from the column bottom part 11 as a drain water.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a distillation apparatus that can achieve high distillation treatment efficiency while aiming for energy conservation, decarbonization, and CO2 reduction.

Background Art

[0002] A general distillation apparatus uses a distillation column for separating components with different boiling points contained in a supplied liquid. The supplied liquid at the bottom of the column is heated by a reboiler, and the high-boiling components are taken out from the top of the column, cooled by a condenser, and taken out as a distillate, while the low-boiling components are taken out as a bottoms liquid from the bottom of the column.

[0003] Conventional distillation apparatuses have used steam supplied from a boiler as a heat source for the reboiler. However, for energy conservation, decarbonization, and CO2 reduction, there is a disclosed apparatus that uses heated warm water generated by a heat pump using the waste warm water of the cooling water supplied to the condenser as the heat source for the reboiler (see Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in the distillation apparatus described in Patent Document 1, a heat circulation heating system is configured that generates heated warm water, which is the heat source for the reboiler, using a heat pump with the waste warm water of the condenser as the heat source. However, since the heat source supplied from the heat pump to the reboiler is heated warm water, it has not been possible to obtain a higher distillation treatment efficiency compared to the steam heat source supplied to the reboiler by a conventional boiler.

[0006] The present invention has been made in view of the above, and aims to provide a distillation apparatus that can achieve high distillation efficiency while saving energy, decarbonizing, and reducing CO2 emissions. [Means for solving the problem]

[0007] To solve the above-mentioned problems and achieve the objective, the distillation apparatus according to the present invention is a distillation apparatus that supplies a feed liquid containing components with different boiling points to a distillation column, heats the feed liquid at the bottom of the column with a reboiler, cools the low-boiling point components from the top of the column with a condenser and extracts them as distillate, and extracts the high-boiling point components from the bottom of the column as bottom extract, and is characterized by comprising a heat pump type steam generation unit that generates heated steam by heating the reboiler waste water, which is the waste hot water of the reboiler circulating water that heats the reboiler, using the waste hot water of the condenser circulating water that cools the condenser as a heat source, and supplies the heated steam to the reboiler.

[0008] Furthermore, the distillation apparatus according to the present invention is characterized in that, in the above invention, the heat pump type steam generation unit has a steam separator that heats the reboiler waste hot water with a condenser and separates the heated gas-liquid two-phase water reboiler waste hot water into saturated steam and hot water, and circulates the hot water from the steam separator to the condenser side.

[0009] Furthermore, the distillation apparatus according to the present invention is characterized in that, in the above invention, a condenser-side storage tank is provided between the condenser and the heat pump type steam generation unit, and the condenser exhaust hot water is stored in the condenser-side storage tank.

[0010] Furthermore, the distillation apparatus according to the present invention is characterized in that, in the above invention, a reboiler-side storage tank is provided between the reboiler and the heat pump-type steam generation unit, and the hot water exhausted from the reboiler is stored in the reboiler-side storage tank.

[0011] Furthermore, the distillation apparatus according to the present invention is characterized in that, in the above invention, the distillation column is provided with a temperature sensor for detecting the temperature inside the distillation column, and the heat pump type steam generation unit controls the supply of the heated steam based on the temperature detected by the temperature sensor so that the temperature inside the distillation column is between the low boiling point temperature of the low boiling point component and the high boiling point temperature of the high boiling point component. [Effects of the Invention]

[0012] According to the present invention, high distillation efficiency can be obtained while achieving energy conservation, decarbonization, and CO2 reduction. [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 is a schematic diagram showing the configuration of a distillation apparatus according to an embodiment of the present invention. [Modes for carrying out the invention]

[0014] Hereinafter, embodiments for carrying out this invention will be described with reference to the attached drawings.

[0015] Figure 1 is a schematic diagram showing the configuration of a distillation apparatus 1 according to an embodiment of the present invention. The distillation apparatus 1 includes a distillation column 10, a reboiler 13, a condenser 14, and a heat pump type steam generation unit 20. A feed liquid containing components with different boiling points is supplied to the distillation column 10, the feed liquid at the bottom 11 of the column is heated by the reboiler 13, the low-boiling point components are removed from the top 12 of the column by the condenser 14, and the high-boiling point components are removed from the bottom 11 as bottom liquid, thus performing a distillation process that separates the low-boiling point components from the high-boiling point components.

[0016] The reboiler 13 heats the circulating feed liquid in the distillation column 10 with heated steam from the reboiler circulating water supplied from the heat pump type steam generation unit 20 via piping L1. The heated reboiler waste hot water, which has condensed after heating the feed liquid, is returned to the heat pump type steam generation unit 20 via piping L2 and then circulated as heated steam. The reboiler 13 may also be located inside the distillation column 10.

[0017] The condenser 14 uses the condenser circulating water supplied from the heat pump type steam generation unit 20 via piping L3 as cooling water to cool the low-boiling point components. The condensed low-boiling point components are stored in the receiver 15, then sent out as distillate, with a portion being refluxed to the distillation column 10 as reflux liquid. After cooling in the condenser 14, the condenser circulating water is returned to the heat pump type steam generation unit 20 via piping L4 as condenser waste hot water. After heat recovery, it is circulated again as cooling water via piping L3 and supplied back to the condenser 14.

[0018] The heat pump type steam generation unit 20 has a heat pump unit 30 and a steam generation unit 40. The heat pump unit 30 forms a heat pump cycle in which a compressor 32 for compressing a refrigerant, a condenser 33 for condensing the refrigerant compressed by the compressor 32 by heat exchange with hot water from the reboiler, an expansion valve 34 which is an expansion mechanism for reducing the pressure of the refrigerant condensed in the condenser 33, and an evaporator 31 for evaporating the refrigerant expanded by the expansion valve 34 using heat recovered from the hot water from the condenser are connected in a ring shape.

[0019] The steam generation unit 40 supplies hot water from the reboiler to the condenser 33, heats this hot water with the refrigerant in the condenser 33, and performs a thermosiphon circulation in which the heated gas-liquid two-phase hot water from the reboiler is recirculated by a steam separator 41 that separates the hot water into saturated steam and hot water, and also supplies the saturated steam as heating steam to the reboiler 13 via the steam separator 41. This heating steam is supplied to the reboiler 13 via a pressure regulating valve V40.

[0020] Incidentally, the reboiler drain warm water in the pipe L2 is stored in the storage tank 52 which is a reboiler-side storage tank, and then supplied to the condenser 33 side via the pump P2. Further, the condenser drain warm water in the pipe L4 is stored in the storage tank 51 which is a condenser-side storage tank, and then supplied to the evaporator 31 side via the pump P1. These storage tanks 51 and 52 are buffer tanks provided to absorb the flow rate difference before and after the storage tanks 51 and 52. Incidentally, the heat exchanger 53 is a heat exchanger for releasing excess heat energy to the outside to achieve heat balance.

[0021] The control unit C controls the operation of the heat pump unit 30 and the steam generation unit 40. The control unit C controls the rotational speed of the compressor 32 and the opening degree of the expansion valve 34 based on the outlet refrigerant temperature and outlet refrigerant pressure of the evaporator 31, the drain warm water temperature at the inlet of the evaporator 31, the inlet refrigerant temperature and inlet refrigerant pressure of the compressor 32, as well as the outlet refrigerant temperature and outlet refrigerant pressure, the inlet refrigerant temperature and inlet refrigerant pressure of the condenser 33, as well as the outlet refrigerant temperature and outlet refrigerant pressure, the outlet refrigerant temperature and outlet refrigerant pressure of the expansion valve 34, etc. Further, the control unit C adjusts the opening degree of the pressure regulating valve V40 based on the temperature and pressure of the heating steam output from the steam separator 41, and controls so that the temperatures detected by the temperature sensors T1 and T2 in the distillation column 10 are between the temperature of the low-boiling component and the temperature of the high-boiling component.

[0022] For example, when the supplied liquid is a mixture of ethanol and water, since the boiling point of ethanol is 78°C and the boiling point of water is 100°C, the control unit C adjusts the temperature and pressure of the heating steam so that the temperature in the distillation column 10 becomes 90°C, for example.

[0023] In this embodiment, a heat circulation mechanism for heating the reboiler 13 using the heat pump type steam generation unit 20 is formed. Specifically, the condenser circulating water (cooling water) flowing through the pipe L3 is at 40 to 70°C, and the condenser discharged warm water flowing through the pipe L4 is at 50 to 80°C. Further, the heating steam flowing through the pipe L1 is at 105 to 150°C, and the reboiler discharged warm water flowing through the pipe L2 is at 90 to 95°C. Thereby, the temperature difference between the temperature of the condenser discharged warm water and the temperature of the heating steam can be made higher than 40°C.

[0024] Here, the physical properties of the heating steam are that it is a heat source with a large amount of retained heat and can stably supply an optimal temperature. That is, steam is a heat energy medium that can be heated at a constant temperature even if it loses energy as long as the pressure is maintained constant, and stable temperature control is possible. In addition, since it is heated by the latent heat released when the heating steam condenses and undergoes a phase change, heating can be performed faster than in the case of hot water heating. Also, since steam can be introduced due to the phase change, no power is required for steam introduction.

[0025] In particular, in this embodiment, since it is possible to supply a sufficient and stable amount of heat to the distillation column 10, there is no need to perform a pressure reduction by a vacuum suction mechanism to lower the boiling point, and thus there is no need to provide a vacuum suction mechanism for that purpose.

[0026] That is, in this embodiment, since the heat circulation by the heat pump type steam generation unit 20 is performed by steam heating, it is possible to obtain a high distillation treatment efficiency equivalent to that when using a boiler and achieve energy saving. In addition, since no boiler or the like is used, decarbonization and CO2 reduction can be achieved.

[0027] Note that the distillation apparatus 1 is not limited to alcohol-based substances such as ethanol described above, and can be applied to a wide range of fields where hydrocarbons such as toluene and petrochemical substances such as benzene are also distillation targets.

[0028] Furthermore, the configurations illustrated in the above embodiments and modifications are functionally schematic and do not necessarily have to be physically represented as shown. In other words, the forms of distribution and integration of each device and component are not limited to those shown, and all or part of them can be functionally or physically distributed and integrated in any unit according to various usage situations. [Explanation of Symbols]

[0029] 1. Distillation apparatus 10 Distillation column 11 Tower bottom 12 Tower top 13 Reboiler 14 Capacitors 15 Receiver 20 Heat pump type steam generation unit 30 Heat pump section 31 Evaporator 32 Compressors 33 Condenser 34 Expansion valve 40 Steam generation section 41. Steam separator 51, 52 Storage tanks 53 Heat exchanger C control section L1~L4 Piping T1, T2 temperature sensors V40 Pressure Regulating Valve

Claims

1. A distillation apparatus that supplies a feed liquid containing components with different boiling points to a distillation column, heats the feed liquid at the bottom of the column with a reboiler, cools the low-boiling point components from the top of the column with a condenser and extracts them as distillate, and extracts the high-boiling point components from the bottom of the column as bottom output, A heat pump type steam generation unit generates heated steam by heating the hot water from the hot water circulating in the reboiler, which heats the hot water from the hot water circulating in the reboiler, using the hot water circulating in the condenser, which heats the reboiler, as a heat source, and supplies the heated steam to the reboiler via a pressure regulating valve. A temperature sensor for detecting the temperature inside the distillation column, A steam separator is provided in the heat pump type steam generation unit, which heats the reboiler exhaust hot water with a condenser and separates the heated gas-liquid two-phase water reboiler exhaust hot water into saturated steam and hot water, Control unit and It has, The heat pump type steam generation unit forms a heat pump cycle in which a compressor for compressing a refrigerant, a condenser for condensing the refrigerant compressed by the compressor by exchanging heat with hot water from a reboiler, an expansion valve which is an expansion mechanism for reducing the pressure of the refrigerant condensed in the condenser, and an evaporator for evaporating the refrigerant expanded by the expansion valve using heat recovered from hot water from a condenser, are connected in a ring shape. The control unit, Based on the temperature detected by the temperature sensor, the supply of the heating vapor is controlled so that the temperature inside the distillation column is between the low boiling point temperature of the low boiling point component and the high boiling point temperature of the high boiling point component. Based on the temperature and pressure of the heated steam output from the steam separator, the opening degree of the pressure regulating valve is adjusted. A distillation apparatus characterized by controlling the rotational speed of the compressor and the opening degree of the expansion valve based on the outlet refrigerant pressure of the evaporator, the inlet refrigerant temperature and inlet refrigerant pressure of the compressor, and the outlet refrigerant pressure of the expansion valve.

2. A distillation apparatus that supplies a feed liquid containing components with different boiling points to a distillation column, heats the feed liquid at the bottom of the column with a reboiler, cools the low-boiling point components from the top of the column with a condenser and extracts them as distillate, and extracts the high-boiling point components from the bottom of the column as bottom output, A heat pump type steam generation unit generates heated steam by heating the hot water from the hot water circulating in the reboiler, which heats the hot water from the hot water circulating in the reboiler, using the hot water circulating in the condenser, which heats the reboiler, as a heat source, and supplies the heated steam to the reboiler via a pressure regulating valve. A temperature sensor for detecting the temperature inside the distillation column, A steam separator is provided in the heat pump type steam generation unit, which heats the reboiler exhaust hot water with a condenser and separates the heated gas-liquid two-phase water reboiler exhaust hot water into saturated steam and hot water, Control unit and It has, The heat pump type steam generation unit forms a heat pump cycle in which a compressor for compressing a refrigerant, a condenser for condensing the refrigerant compressed by the compressor by exchanging heat with hot water from a reboiler, an expansion valve which is an expansion mechanism for reducing the pressure of the refrigerant condensed in the condenser, and an evaporator for evaporating the refrigerant expanded by the expansion valve using heat recovered from hot water from a condenser, are connected in a ring shape. The control unit, Based on the temperature detected by the temperature sensor, the supply of the heating vapor is controlled so that the temperature inside the distillation column is between the low boiling point temperature of the low boiling point component and the high boiling point temperature of the high boiling point component. Based on the temperature and pressure of the heated steam output from the steam separator, the opening degree of the pressure regulating valve is adjusted. A distillation apparatus characterized by controlling the rotational speed of the compressor and the opening degree of the expansion valve based on one or more of the following: the outlet refrigerant temperature and outlet refrigerant pressure of the evaporator; the exhaust hot water temperature at the inlet of the evaporator; the inlet refrigerant temperature and inlet refrigerant pressure and outlet refrigerant temperature and outlet refrigerant pressure of the compressor; the inlet refrigerant temperature and inlet refrigerant pressure and outlet refrigerant temperature and outlet refrigerant pressure of the condenser; and the outlet refrigerant temperature and outlet refrigerant pressure of the expansion valve.

3. The control unit is The distillation apparatus according to claim 2, characterized in that the rotational speed of the compressor and the opening degree of the expansion valve are controlled based on four or more of the following: the outlet refrigerant temperature of the evaporator, the outlet refrigerant pressure, the waste hot water temperature at the inlet of the evaporator, the inlet refrigerant temperature and the inlet refrigerant pressure of the compressor, the outlet refrigerant temperature and the outlet refrigerant pressure of the condenser, and the outlet refrigerant temperature and the outlet refrigerant pressure of the expansion valve.

4. The distillation apparatus according to claim 1 or 2, characterized in that the hot water from the steam separator is circulated to the condenser side.

5. The distillation apparatus according to claim 1 or 2, characterized in that a condenser-side storage tank is provided between the condenser and the heat pump-type steam generation unit, and the condenser exhaust hot water is stored in the condenser-side storage tank.

6. The distillation apparatus according to claim 1 or 2, characterized in that a reboiler-side storage tank is provided between the reboiler and the heat pump-type steam generation unit, and the hot water exhausted from the reboiler is stored in the reboiler-side storage tank.

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