Anti-thermosensitization rectification tower and the rectification process thereof for separating thermosensitive natural substances

Patent metadata

Field	Value
Publication number	US-10039998-B2
Application number	US-201113701840-A
Country	US
Kind code	B2
Filing date	Mar 14, 2011
Priority date	Oct 14, 2010
Publication date	Aug 7, 2018
Grant date	Aug 7, 2018

Abstract

An anti-thermosensitization rectification tower comprising a rectification tower, a T-shaped condenser, a baffle plate, a tower bottom, a falling-film reboiler and a recirculation system, wherein the T-shaped condenser is secured exactly on the top of the rectification tower without any pipeline in between, and the circular baffle plate is installed in the T-shaped condenser; an annular sump located between the rectification tower and the T-shaped condenser for collecting the liquid condensed in the T-shaped condenser and channeling it out of the rectification tower into a liquid-collecting tank, and a centrifugal pump utilized to connect together the tower bottom and the falling-film reboiler to form a high-speed circulation system, wherein the tower bottom is an elongated conduit and the falling-film reboiler is in the form of a stout shell-and-tube heat exchanger is provided.

First claim

What is claimed is:

1. A rectification system comprising:
a rectification tower;
a T-shaped condenser comprising a horizontal section perpendicular to the rectification tower and a vertical section perpendicular to the horizontal section, the horizontal section being wider than the vertical section, wherein a coolant of the T-shaped condenser is introduced to the T-shaped condenser through a coolant inlet pipe and channeled out through a coolant outlet pipe, the coolant flowing through the T-shaped condenser in a mainly horizontal direction, perpendicular to the rectification tower, across a width of the horizontal section of the T-shaped condenser, further wherein a vertical distance between the coolant inlet pipe and the coolant outlet pipe is less than a horizontal distance between the inlet coolant pipe and the outlet coolant pipe;
a circular baffle plate positioned within the horizontal section of the T-shaped condenser;
a tower bottom;
a falling-film reboiler;
a recirculation system, wherein the T-shaped condenser is secured exactly on the top of the rectification tower without any pipeline in between, and the circular baffle plate is installed in the T-shaped condenser;
an annular sump located below the circular baffle plate and between the rectification tower and the T-shaped condenser for collecting the liquid condensed in the T-shaped condenser and channeling the liquid out of the rectification tower via a first pipe positioned below the circular baffle plate, connecting the annular sump to a liquid-collecting tank; and
a centrifugal pump utilized to connect together the tower bottom and the falling-film reboiler to form the recirculation system;
wherein the tower bottom is conduit having a length that is larger than a diameter of the conduit and the falling-film reboiler is a stout shell-and-tube heat exchanger.

2. The rectification system as defined in claim 1 , wherein the rectification tower is a plate or packed tower.

3. The rectification system as defined in claim 2 , wherein the rectification tower is a packed tower.

4. The rectification system as defined in claim 1 , wherein the T-shaped condenser and the rectification tower are connected together by means of a flange.

5. The rectification system as defined in claim 1 , wherein the annular sump is located at a top outlet of the rectification tower; a brim of the annular sump is higher than a connecting section of the rectification tower and the T-shaped condenser, and the connecting section is spaced apart from the circular baffle plate in such a manner that the liquid condensed in the T-shaped condenser can only flow into the annular sump.

6. The rectification system as defined in claim 1 , wherein the circular baffle plate is welded on the rectification tower above a connecting section of the rectification tower and the T-shaped condenser, and the connecting section has a certain clearance to the top of the rectification tower so that upward-moving steam can emit through the circular baffle plate; and the circular baffle plate overlaps an inner brim of the annular sump so that the liquid condensed in the T-shaped condenser can only flow into the annular sump, rather than back into the rectification tower.

7. The rectification system as defined in claim 1 , wherein the falling-film reboiler is in the form of a stout cylinder; the centrifugal pump moves the liquid from the tower bottom through the falling-film reboiler with an average top-down retention time of the liquid in the falling-film reboiler being 0.1-3 seconds.

8. The rectification system as defined in claim 1 , wherein the recirculation system further comprises:
a second pipe connecting the liquid-collecting tank to a second centrifugal pump; and
a third pipe connecting the second centrifugal pump to the rectification tower, wherein the liquid-collecting tank-collects the liquid flowing out of the annular sump and a part of the liquid in the liquid-collecting tank is channeled by the second centrifugal pump back into the rectification tower for recirculation while a remainder of the liquid is discharged as a final product.

9. A rectification process for continuously separating thermosensitive natural substances using the rectification system as defined in claim 1 comprising the steps of:
reducing a pressure in the rectification tower through a vacuum system;
introducing the liquid comprising the thermosensitive natural substances into the rectification tower through a feeding inlet;
turning on the centrifugal pump when the liquid in the tower bottom reaches a certain level;
pumping the liquid in the tower bottom through a first pipe into the falling-film reboiler for heating wherein due to a pressure difference, a gas-liquid mixture generated from the liquid, flows through a first pipe into the rectification tower for rectification processing;
a gas of the gas-liquid mixture entering the rectification tower flows into the T-shaped condenser and is cooled into a condensed liquid therein, wherein the gas flows upward into the t-shaped condenser from the rectification tower and the gas is cooled below a thermosensitization point;
flowing the condensed liquid-over the circular baffle plate into the annular sump;
further flowing the condensed liquid through a second pipe into the liquid-collecting tank;
channeling the condensed liquid from the liquid-collecting tank through a third pipe into a second centrifugal pump;
pumping the liquid from the second centrifugal pump back into the rectification tower, establishing a full recirculation;
opening a first valve and a second valve after establishing a reaction equilibrium;
discharging a final product from the first valve connected to the liquid-collecting tank at the top of the rectification tower, wherein a light component of a distillate of the liquid is discharged out from the first valve and a heavy component of the distillate of the liquid discharges at the tower bottom from the second valve while simultaneously introducing via the feed inlet an additional amount of the liquid to maintain the liquid in the tower bottom at constant level so that the rectification process operates continuously.

10. A rectification system comprising:
a rectification tower, a T-shaped condenser comprising a horizontal section perpendicular to the rectification tower and a vertical section perpendicular to the horizontal section, a circular baffle plate, a tower bottom, a falling-film reboiler and a recirculation system, wherein the T-shaped condenser is secured exactly on the top of the rectification tower without any pipeline in between, and the circular baffle plate is installed in the T-shaped condenser, wherein a coolant of the T-shaped condenser is introduced to the T-shaped condenser through a coolant inlet pipe and channeled out through a coolant outlet pipe, the coolant flowing through the T-shaped condenser in a mainly horizontal direction, perpendicular to the rectification tower, across a width of the horizontal section of the T-shaped condenser, further wherein a vertical distance between the coolant inlet pipe and the coolant outlet pipe is less than a horizontal distance between the inlet coolant pipe and the outlet coolant pipe;
an annular sump located below the circular baffle plate and between the rectification tower and the T-shaped condenser for collecting the liquid condensed in the T-shaped condenser and channeling the liquid out of the rectification tower via a first pipe positioned below the circular baffle plate, connecting the annular sump to a liquid-collecting tank; and
a centrifugal pump utilized to connect together the tower bottom and the falling-film reboiler to form a circulation system;
wherein the tower bott

Assignees

• Zhang Zhibing
• Zhou Zheng
• Yang Gaodong
• Sun Defang
• Zhang Ling
• Nanjing University Of Technology

Inventors

• Zhang Zhibing
• Zhou Zheng
• Yang Gaodong
• Sun Defang
• Zhang Ling

Classifications

• B01D3/14

  Fractional distillation {or use of a fractionation or rectification column} · CPC title

• B01D3/148 Primary

  in combination with at least one evaporator · CPC title

• B01D5/006

  with evaporation or distillation · CPC title

• B01D3/28 Primary

  Fractionating columns with surface contact and vertical guides, e.g. film action · CPC title

• B01D3/322

  Reboiler specifications · CPC title