High-efficiency rectifying tower for acetone production

Abstract

The utility model provides a kind of high-efficiency rectifying column for acetone production, solve the problem that acetone is only operated under normal pressure due to the heat sensitivity of acetone, resulting in relatively weak acetone vapor mass transfer driving force, low separation efficiency from liquid, and further affect the processing efficiency of the entire acetone. The utility model prolongs the vapor mass transfer path by setting a two-stage cover structure composed of an arched bubble cover and a triangular flow guide cover, improves the single board mass transfer efficiency, and successfully solves the problem of low separation efficiency caused by insufficient acetone vapor mass transfer driving force under normal pressure operation.

Description

Technical Field

[0001] This utility model relates to the field of acetone production technology, and in particular to a high-efficiency distillation column for acetone production. Background Technology

[0002] Ethyl ketone (EK) is an organic chemical raw material and an excellent solvent, widely used in synthetic fibers, pharmaceuticals, coatings, plastics, and many other fields. In the industrial production of EK, distillation is a key operation for separating and purifying the final product. Because EK is heat-sensitive and may generate peroxides at high temperatures, peroxides are extremely unstable when concentrated or heated or subjected to shock, posing a significant safety risk of violent decomposition or even explosion. This means that EK is usually only operated at atmospheric pressure, resulting in a relatively weak driving force for mass transfer of EK vapor and low separation efficiency from the liquid, which in turn affects the overall processing efficiency of EK. Utility Model Content

[0003] To address the problem in the background art that ethyl ketone is heat-sensitive and can only be operated at atmospheric pressure, resulting in relatively weak mass transfer driving force for ethyl ketone vapor and low separation efficiency from the liquid, thus affecting the overall processing efficiency of ethyl ketone, this utility model proposes a high-efficiency distillation column for ethyl ketone production.

[0004] The technical solution of this utility model is: a high-efficiency distillation column for acetone production, including a column body and multiple tray assemblies disposed therein. The tray assembly includes a circular tray with a notch on one side, and an overflow plate is provided on one side of the notch of the circular tray. The overflow plate and the inner wall of the column body form a downcomer channel. The circular tower plate has multiple air risers arranged in a triangle. Each air riser is fixed above an arched bubble hood, and the side wall of the arched bubble hood has injection holes facing the horizontal direction. The outer cover of the arched bubble cover is a triangular guide shroud, which is an isosceles triangular columnar structure with an acute apex angle. The triangular guide shroud is fixed on the circular tower plate, and air outlets are provided at the two bottom corners of the triangular guide shroud.

[0005] Preferably, the apex of the triangular guide shield faces the direction of liquid flow, and the base of the triangular guide shield is arranged parallel to the overflow plate.

[0006] Preferably, the injection holes of the arched bubble shroud are oriented towards the apex of the triangular guide shroud.

[0007] Preferably, the tower body is provided with a feed pipe in the middle, a steam outlet pipe and a reflux liquid inlet pipe at the top, and a reboiler return pipe and a bottom extraction pipe at the bottom.

[0008] Preferably, a spiral guide vane with a hollow center is fixedly provided on the inner wall of the top of the tower.

[0009] Advantages of this utility model: (1) This utility model extends the steam mass transfer path by setting a double-stage cover structure composed of an arched bubble cover and a triangular guide cover, thereby improving the single-plate mass transfer efficiency and successfully solving the problem of low separation efficiency caused by insufficient driving force of ethyl ketone steam mass transfer under normal pressure operation.

[0010] (2) By setting up a unique triangular flow guide, the flow diversion effect of the triangular flow guide improves the uniformity of liquid distribution. Combined with the continuous cleaning effect of the horizontal jet airflow on the tower plate surface, the dead zone of flow is completely eliminated, the local accumulation of peroxide is avoided, and the inherent safety of the ethyl ketone production process is improved. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This utility model Figure 1 A cross-sectional view of the central tower. Figure 3 This utility model Figure 2 Schematic diagram of the tower tray component structure Figure 1 ; Figure 4 This utility model Figure 2 Schematic diagram of the tower tray component structure Figure 2 ; Figure 5 This is an exploded view of the bubble cover and triangular guide cover of this utility model.

[0013] In the diagram: 1. Tower body; 2. Tray assembly; 201. Circular tray; 202. Overflow plate; 203. Gas riser hole; 3. Bubble cover; 4. Triangular guide cover; 5. Feed pipe; 6. Steam outlet pipe; 7. Reflux liquid inlet pipe; 8. Reboiler return pipe; 9. Bottom extraction pipe. Detailed Implementation

[0014] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0015] Example 1: A high-efficiency distillation column for acetone production, such as... Figure 1-5 As shown, it includes a tower body 1, which is a vertically arranged cylindrical structure. Multiple layers of horizontally arranged tower tray assemblies 2 are fixed inside the tower body 1. The multiple layers of tower tray assemblies 2 are arranged at intervals. The tower tray assemblies 2 are fixed to the inner wall of the tower body 1 by support rings.

[0016] The tray assembly 2 includes left overflow trays and right overflow trays arranged alternately. Specifically, odd-numbered trays use left overflow trays, and even-numbered trays use right overflow trays. The overflow weirs of two adjacent tray assemblies 2 are alternately arranged on both sides of the tower axis, so that the liquid flows downward in an S-shaped path inside the tower. The tray assembly 2 includes a circular tray 201. A notch is opened on one side of the circular tray 201, and an overflow plate 202 is vertically fixed at the notch. The top of the overflow plate 202 is higher than the circular tray 201 to form an overflow weir, and the bottom of the overflow plate 202 extends downward to below the circular tray 201. The overflow plate 202 and the inner wall of the tower 1 together form a downcomer channel. This structure can effectively guide the liquid to form a closed liquid curtain and prevent vapor short circuit.

[0017] The circular tray 201 has multiple triangularly arranged air risers 203. To increase the flow path of steam through the air risers 203 and the acetone-containing mixture on each tray assembly 2, an arched bubble hood 3 is fixed above each air riser 203. The side wall of the arched bubble hood 3 has horizontally oriented injection holes. After the steam enters the bubble hood 3 through the air riser 203, it is horizontally ejected from the side injection holes. The arched bubble hood 3 addresses the problem of low acetone vapor density and weak mass transfer driving force under normal pressure by converting vertical airflow into horizontal injection. While maintaining safe operation at normal pressure, it significantly enhances the turbulence and contact efficiency of the vapor and liquid phases.

[0018] To further compensate for insufficient mass transfer driving force under atmospheric pressure operation, the outer cover of the arched bubble hood 3 is a triangular guide hood 4. The triangular guide hood 4 is an isosceles triangular columnar structure with an acute apex angle. The triangular guide hood 4 is fixed on the circular tray 201. Two gas outlets are provided at the two base corners of the triangular guide hood 4. The injection holes of the arched bubble hood 3 face the apex corner of the triangular guide hood 4 and are far away from the two gas outlets of the triangular guide hood 4. This causes the vapor to undergo two turns and velocity changes on the single tray assembly 2, effectively extending the mass transfer path and solving the technical bottleneck of low separation efficiency in atmospheric pressure distillation. The apex corner of the arched bubble hood 3 faces the direction of liquid flow, and the bottom edge of the arched bubble hood 3 is arranged parallel to the overflow plate 202. This structure can evenly distribute the liquid entering the tray to both sides, while the vapor ejected from the outlet hole provides auxiliary power for the liquid flow, effectively eliminating flow dead zones and avoiding local accumulation of peroxides.

[0019] A feed pipe 5 is fixedly connected to the outer wall of the middle section of the tower body 1. The feed pipe 5 is connected to an external feed pump and preheater to feed the acetone-containing mixture to be separated into the tower. A steam outlet pipe 6 is fixedly connected to the top of the tower body 1. The steam outlet pipe 6 is connected to a condenser, where the steam at the top of the tower is condensed into liquid. A reflux liquid inlet pipe 7 is fixedly connected to the outer wall of the top of the tower body 1. The condenser is connected to a reflux tank. One outlet of the reflux tank is connected to the reflux liquid inlet pipe 7 through a reflux pipe. The reflux pipe is equipped with a reflux... A flow pump is used to pump a portion of the condensate back to the top of the column as reflux liquid. The other outlet of the reflux tank is a product collection pipe, used to collect high-purity ethyl ketone product. A reboiler return pipe 8 is fixedly connected to the bottom outer wall of column body 1. The reboiler return pipe 8 is connected to the outlet of the external reboiler. A bottom extraction pipe 9 is fixedly connected to the bottom of column body 1. The bottom extraction pipe 9 is connected to the inlet of the external reboiler. The reboiler uses steam to partially vaporize the liquid at the bottom of the column. The steam generated is returned to column body 1 through the return pipe, providing rising steam for the distillation process.

[0020] A spiral guide vane 10 is fixedly installed on the inner wall of the top of the tower body 1. The center of the spiral guide vane 10 is a hollow part, which allows some of the vapor carrying liquid droplets to rotate along the spiral guide vane, generating a strong centrifugal force that throws the denser liquid droplets toward the tower wall. After the liquid droplets collide with the wall, they condense and fall. The pure vapor that has separated the liquid droplets passes directly through the central hollow part, realizing the separation of vapor and liquid phases.

[0021] Working principle: The ethyl ketone-containing feed liquid enters through the feed pipe 5 in the middle of the tower. The steam generated by the reboiler at the bottom of the tower flows from bottom to top and forms a countercurrent contact with the downward liquid on the tray. The steam enters the arched bubble hood 3 through the riser hole 203 on the tray and is ejected from the horizontal injection hole on its side wall, which transforms the vertical airflow into a horizontal jet, significantly enhancing the vapor-liquid contact. Subsequently, the steam enters the triangular guide hood 4, forming a vortex inside the hood and exiting from the bottom corner outlet hole, completing the secondary mass transfer. The steam reaching the top of the tower is finally purified by the spiral guide plate 10, in which the central channel ensures a low pressure drop. After the pure ethyl ketone steam is condensed, part of it is collected as product and part of it is returned to the top of the tower as reflux.

[0022] When the liquid flows on the tray assembly 2, it is evenly diverted to both sides by the apex of the triangular flow guide shroud 4, forming an orthogonal flow contact with the vapor, eliminating the flow dead zone. Through the overflow weirs arranged alternately on the left and right, the liquid flows downward in an S-shaped path in the tower. During the stepwise mass transfer process, acetone is continuously transferred from the liquid phase to the vapor phase, realizing component separation.

[0023] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims and not by the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A high-efficiency distillation column for acetone production, characterized in that: It includes a tower body (1) and multiple tray assemblies (2) inside it. The tray assembly (2) includes a circular tray (201) with a notch on one side. An overflow plate (202) is provided on one side of the notch of the circular tray (201). The overflow plate (202) forms a liquid downcomer channel with the inner wall of the tower body. The circular tower plate (201) is provided with multiple air risers (203) arranged in a triangular pattern. Each air riser (203) is fixedly provided with an arched bubble cover (3) above it. The side wall of the arched bubble cover (3) is provided with injection holes facing the horizontal direction. The outer cover of the arched bubble cover (3) is provided by a triangular guide cover (4). The triangular guide cover (4) is an isosceles triangular column structure with an acute apex angle. The triangular guide cover (4) is fixed on the circular tower plate (201). Air outlets are provided at the two bottom corners of the triangular guide cover (4).

2. The high-efficiency rectifying column for ketone production according to claim 1, characterized in that: The apex of the triangular guide shield (4) faces the direction of the liquid flow, and the bottom edge of the triangular guide shield (4) is arranged parallel to the overflow plate (202).

3. The high-efficiency distillation column for acetone production according to claim 1, characterized in that: The injection holes of the arched bubble cover (3) are oriented toward the apex of the triangular guide cover (4).

4. The high-efficiency distillation column for acetone production according to claim 1, characterized in that: The tower body (1) is provided with a feed pipe (5) in the middle, a steam outlet pipe (6) and a reflux liquid inlet pipe (7) at the top of the tower body (1), and a reboiler return pipe (8) and a bottom extraction pipe (9) at the bottom of the tower body (1).

5. The high-efficiency distillation column for acetone production according to claim 1, characterized in that: The top inner wall of the tower body (1) is fixed with a spiral guide vane (10) with a hollow center.

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