Distillation apparatus and distillation method

Abstract

To reduce required power of a compressor.SOLUTION: A distillation device includes: a batch type distillation column; a reboiler that heats a liquid, supplied to the distillation column, to evaporate the liquid to form vapor; a volumetric compressor that causes a fluid for heating the liquid to flow in so as to raise pressure and temperature of the fluid and supply the fluid to the reboiler; a condenser that condenses column top vapor of the distillation column to obtain a condensate; a distillate vent part for venting the condensate condensed by the condenser; and a column bottom liquid venting part that vents a residual liquid inside the distillation column. The compressor has an actual volume flow rate adjustment mechanism for changing the actual volume flow rate of the fluid the pressure and temperature of which is increased by the compressor in accordance with a change in the heating temperature required by the reboiler during operation of the distillation device.SELECTED DRAWING: Figure 4

Claims

1. A batch-type distillation column, A reboiler that heats the liquid process fluid supplied to the distillation column to evaporate it into vapor, A positive displacement compressor that introduces a fluid for heating the aforementioned liquid, pressurizes and heats the fluid, and supplies it to the reboiler. A condenser for condensing the top vapor of the aforementioned distillation column into a condensate, A distillation apparatus comprising a distillate draining section for extracting the condensate and a bottom draining section for extracting the residual liquid in the distillation column, The fluid retains the heat of condensation of the steam at the top of the tower, and after being pressurized and heated by the compressor, the heat of condensation is transferred to the liquid during condensation in the reboiler, causing it to condense. The compressor has an actual volume flow rate adjustment mechanism that changes the actual volume flow rate of the fluid pressurized and heated by the compressor in accordance with the change in the heating temperature required for the reboiler during the operation of the distillation apparatus. A distillation apparatus characterized by having an indirect heat pump mechanism or a direct heat pump mechanism in which the fluid is the top vapor of the column, the working fluid receives the heat of condensation from the top vapor of the column in the condenser, the working fluid condensed in the reboiler is depressurized by a pressure reducing valve and its temperature is reduced, and it is supplied to the condenser.

2. The distillation apparatus according to claim 1, wherein the distillation column does not have shelves or packing material inside and performs simple distillation without a reflux section that returns the condensate to the distillation column.

3. The distillation apparatus according to claim 1, wherein the distillation column is a rectification column having shelves or packing material inside, and has a reflux section that returns the condensate to the distillation column.

4. The distillation apparatus according to claim 1, wherein the actual volume flow rate adjustment mechanism is a step volume control system.

5. The distillation apparatus according to claim 1, wherein the actual volume flow rate adjustment mechanism is a stepless volume control system.

6. The distillation apparatus according to claim 1, comprising the indirect heat pump mechanism wherein the working fluid that has received the heat of condensation is pressurized and heated by the compressor and condensed in the reboiler, the condensed working fluid is depressurized by a pressure reducing valve and its temperature is reduced, the depressurized working fluid is separated into gas and liquid in a drum, and the liquid portion of the gas and liquid separated working fluid is supplied to the condenser.

7. After the fluid is pressurized and heated by the compressor, the liquid supplied to the distillation column is evaporated by the reboiler. The distillation apparatus according to claim 1, which has a direct heat pump mechanism that condenses the fluid pressurized and heated by the compressor in the reboiler.

8. The distillation apparatus according to claim 7, wherein the distillation column is a rectification column having shelves or packing material inside, has a reflux section that returns the condensate condensed in the reboiler back to the distillation column, and has a pressure reducing valve for reducing the pressure of the condensate condensed in the reboiler and refluxing it back to the distillation column.

9. A feeding process that supplies liquid to a batch-type distillation column, A pressurized heating step involves drawing in a fluid for heating the aforementioned liquid using a positive displacement compressor, pressurizing and heating the fluid, and supplying it to a reboiler. In the reboiler, a heating step is performed in which heat exchange is carried out between the liquid supplied to the distillation column and the pressurized and heated fluid, the liquid is heated to obtain top vapor, and the fluid is condensed. A condensation step is performed in which the steam at the top of the tower is sent to a condenser by heating in the heating step, and the steam at the top of the tower is condensed by heat exchange to form a condensate. A distillate extraction step for removing the condensate, A distillation method comprising a bottom draining step for removing residual liquid from the distillation column, In the aforementioned pressurized heating step, in order to enable the distillation of the liquid by heating with a heat pump operating with a smaller heating range, the actual volume flow rate of the fluid pressurized and heated by the compressor is changed by an actual volume flow rate adjustment mechanism in accordance with the change in the heating temperature required for the reboiler. A distillation method characterized by having an indirect heat pump mechanism or a direct heat pump mechanism in which the fluid is the top vapor of the column, the working fluid receives the heat of condensation from the top vapor of the column in the condenser, the working fluid condensed in the reboiler is depressurized by a pressure reducing valve and its temperature is reduced, and it is supplied to the condenser.

10. The distillation method according to claim 9, wherein the distillation method is a simple distillation operation in a distillation column that does not have shelves or packing material inside and does not have a reflux step to return the condensate to the distillation column.

11. The distillation method according to claim 9, wherein the distillation method is a rectification operation in a distillation column having shelves or packing material inside and a reflux step in which the condensate is returned to the distillation column.

12. The distillation method according to claim 9, wherein the actual volume flow rate adjustment mechanism is a step volume control system.

13. The distillation method according to claim 9, wherein the actual volume flow rate adjustment mechanism is a stepless volume control system.

14. The distillation method according to claim 9, comprising an indirect heat pump mechanism in which the working fluid that has received the heat of condensation is pressurized and heated by the compressor, condensed in the reboiler, depressurized by a pressure reducing valve to lower the temperature, and the liquid portion obtained by gas-liquid separation in a drum is supplied to the condenser.

15. The distillation method according to claim 9, comprising a direct heat pump mechanism in which the fluid is pressurized and heated by the compressor, the liquid supplied to the distillation column is evaporated in the reboiler, and the fluid pressurized and heated by the compressor is condensed in the reboiler.

16. The distillation method according to claim 15, further comprising a depressurization step of reducing the pressure of the condensate of the fluid obtained in the reboiler using a pressure reducing valve, and a reflux step of returning the condensate after the depressurization step to the distillation column.

Images