Method for refining easily polymerizable matter-containing substance and apparatus therefor

• US 20040050681A1
• Filed: 08/15/2003
• Published: 03/18/2004
• Est. Priority Date: 04/05/1999
• Status: Active Grant

• Current Assignee: Takeshi Nishimura, Yukihiro Matsumoto
• Original Assignee: Takeshi Nishimura, Yukihiro Matsumoto
• Inventors: Nishimura, Takeshi, Matsumoto, Yukihiro
• Granted Patent: US 7,253,314 B2
• Time in Patent Office: Days
• US Class Current: 203/99
• CPC Class Codes: B01D 3/14 Fractional distillation or use of a fractionation or rectification column
• CPC Class Codes: B01D 3/322 Reboiler specifications
• CPC Class Codes: B01D 5/0012 Vertical tubes
• CPC Class Codes: B01D 5/0063 Reflux condensation
• CPC Class Codes: Y10S 159/42 Seals

Abstract

A method for refining an easily polymerizable matter while preventing an easily polymerizable matter-containing substance from being polymerized and an apparatus for use in the method are disclosed. The method and apparatus for refining and separating the easily polymerizable matter-containing substance by the use of a distillation column provided with a heat exchanger set the linear velocity of a vapor in a connecting line intervening between the distillation column and the heat exchanger at a level of not less than 5 m per second and the retention time of the vapor at a level of not more than 3 seconds.

Claims

1. A method for refining or separating an easily polymerizable matter-containing substance by the use of a distillation column equipped with a heat exchanger, which method comprises:

setting a linear velocity of the vapor in at least one connecting line between the distillation column and the heat exchanger at a level of not less than 5 m per second and a retention time of the vapor in the (inter) connecting line at a level of not more than 3 seconds excluding zero.

2. A method according to claim 1, wherein the linear velocity is in the range of 5 to 60 m/s.

3. A method according to claim 2, wherein the linear velocity is in the range of 20 to 60 m/s.

4. A method according to claim 1, wherein the retention time is at a level of not more than 2 seconds excluding zero.

5. A method according to claim 1, wherein the heat exchanger is a vertical shell-and-tube heat exchanger and is supported to the distillation column.

6. A method according to claim 5, wherein the connecting line for the vapor connected to the heat exchanger is disposed to the straight shell part of the distillation column.

7. A method according to claim 1, wherein the heat exchanger comprises at least two items of a condenser and a re-boiler.

8. A method according to claim 1, wherein the heat exchanger is a condenser and is disposed directly in the top part of the distillation column.

9. A method according to claim 7, wherein the heat exchanger is a re-boiler and the re-boiler being disposed directly inside the distillation column in the lower part thereof wherein a vapor guide provided above the heating tubes for the re-boiler is opened into the vapor phase part of the column and a down-take is furnished outside the heating tubes.

10. A method according to claim 1, wherein an inner diameter, against the flow of the vapor, of the connecting line substantially coincides to that of the shell of the heat exchanger.

11. A method according to claim 1, wherein the easily polymerizable matter is a vinyl compound.

12. A method according to claim 11, wherein the vinyl compound is (meth)acrylic acid and/or a (meth)acrylic ester.

13. An apparatus for refining an easily polymerizable matter-containing substance comprising:

a distillation column, and

a heat exchanger disposed directly in the top part of the distillation column,

wherein the heat exchanger serves as a condenser.

14. An apparatus according to claim 13 further comprising a re-boiler, wherein a (inter)connecting line for the vapor connected to the re-boiler is connected to the lower lateral part of the distillation column.

17. An apparatus according to claim 14 further comprising a condenser, wherein a (inter)connecting line for the vapor connected to the condenser is connected to the upper straight shell of the distillation column.

15. An apparatus for refining an easily polymerizable matter-containing substance comprising:

a distillation column, and

a heat exchanger disposed directly in the lower part inside the distillation column, in which a vapor guide provided above the heating tubes for the exchanger is opened into the vapor phase part of the column and a down-take is furnished outside the heating tubes,

wherein the heat exchanger serving as a re-boiler.

16. An apparatus according to claim 15, wherein the re-boiler comprises:

a cylindrical vessel provided on the lateral side thereof with an inlet and an outlet for a heating medium and tightly sealed in the upper and lower part thereof,

a plurality of heat transfer tubes disposed between the upper and lower sides of the cylindrical vessel and provided respectively therein with a vertically piercing hole,

a vapor guide disposed above the cylindrical vessel and having a vapor vent positioned approximately in the central part of the distillation column,

a loose lid disposed on or above the vapor vent, and

a down-take disposed in such a manner outside the heating tube as to join the upper and lower parts of the cylindrical vessel.