High boiling depth separation device

Abstract

The utility model relates to a high boiling depth separating device which comprises a rectifying tower, the top of the rectifying tower is connected with a condenser through a gas phase pipeline I, the rear end of the condenser is connected with a reflux tank, the reflux tank is connected with a cracking kettle through a cracking kettle feeding pipeline, and the cracking kettle is connected with a cracking tower. According to the utility model, high-boiling residues of raw materials can be deeply separated, and the recovery rate of the high-boiling residues can be improved; high-boiling-point substances which do not participate in cracking reaction are separated through the rectifying tower, the situation that a large number of non-reaction high-boiling-point substances occupy the volume of the cracking kettle is avoided, the utilization rate of the cracking kettle is increased, meanwhile, the operation cycle of the cracking kettle is prolonged, the kettle stopping frequency is reduced, and then the processing capacity of the cracking device is improved.

Description

Technical Field

[0001] The utility model relates to a high boiling depth separation device, belonging to the technical field of organosilicon production. Background Art

[0002] Under the action of the catalyst N,N-dimethylaniline, high-boiling substances react with hydrogen chloride to undergo a cracking reaction. Disilane containing Si-Si bonds is cracked to form Si-H and Si-Cl bonds, generating new methylchlorosilane monomers. The methylchlorosilane monomers are heated and evaporated into the cracking tower. After initial distillation in the cracking tower, they are extracted and sent to the monomer separation process for further separation and purification. Due to the complex composition of high-boiling substances, only a portion of them participate in the cracking reaction. As production continues, high-boiling substances that do not participate in the reaction accumulate in the cracking kettle, occupying the cracking kettle volume and affecting the cracking kettle's processing capacity. Therefore, the cracking unit needs to be shut down regularly to discharge the high-boiling residual liquid. Utility Model Content

[0003] To address the above-mentioned issues, the present invention provides a high-boiling-point separation technology that fractionates the high-boiling materials in the raw materials by distillation. Based on the compositional differences of the high-boiling materials in the raw materials, the corresponding high-boiling materials that are suitable for cracking are separated. The technical solution of the present invention is to install a distillation tower at the front end of the cracking kettle. After separating the high-boiling materials in the raw materials, the distilled materials are then transferred to the cracking kettle for cracking. The methylchlorosilane monomer generated by the reaction is heated and evaporated into the cracking tower for further separation. Finally, new methylchlorosilane monomer is extracted from the top of the cracking tower to obtain new methylchlorosilane monomer.

[0004] A high boiling depth separation device comprises a distillation tower, the top of which is connected to a condenser via a gas phase pipeline, the rear end of the condenser is connected to a reflux tank, the reflux tank is connected to a cracking kettle via a cracking kettle feed pipeline, and the cracking kettle is connected to the cracking tower; a high boiling material feed port is provided in the middle of the distillation tower, and a reboiler is connected to the lower part.

[0005] The reboiler is provided with a steam inlet at the top, a steam condensate outlet at the bottom, and a gas phase pipeline three connected to the distillation tower at the top.

[0006] The bottom of the distillation tower is connected to the reboiler via a liquid phase pipeline 1, and a residual liquid extraction port 502 is also provided at the bottom of the distillation tower.

[0007] The reflux tank is connected to the distillation tower through a reflux pipeline.

[0008] The top of the cracking kettle is provided with a hydrogen chloride feed port, and the top is also provided with a second gas phase pipeline and a second liquid phase pipeline connected to the cracking tower.

[0009] The top of the cracking tower is connected to a crude monomer extraction pipeline.

[0010] The cracking kettle is provided with a jacket outside.

[0011] Beneficial effects of the utility model:

[0012] 1. Deep separation of high-boiling substances in raw materials can improve the recovery rate of high-boiling substances;

[0013] 2. The high-boiling products that do not participate in the cracking reaction are separated by the distillation tower, so as to avoid a large amount of non-reactive high-boiling products occupying the cracking kettle volume, improve the utilization rate of the cracking kettle, and at the same time extend the operation cycle of the cracking kettle, reduce the frequency of shutdown, and thus improve the processing capacity of the cracking unit;

[0014] 3. The high-boiling substances in the raw materials are distilled and separated before cracking reaction to reduce the amount of high-boiling residual liquid to be processed. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of the device of the present utility model.

[0016] Description of the markings in the figure: cracking kettle 1, condenser 2, reflux tank 3, cracking tower 4, distillation tower 5, reboiler 6, gas phase pipeline one 7, cracking kettle feed pipeline 8, gas phase pipeline two 9, liquid phase pipeline two 10, crude monomer production pipeline 11, hydrogen chloride feed port 12, high boiling material feed port 501, residual liquid production port 502, liquid phase pipeline one 503, steam inlet 601, steam condensate outlet 602, gas phase pipeline three 603. DETAILED DESCRIPTION

[0017] The embodiments of the present invention will be described in detail below with reference to the examples. The following examples are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention.

[0018] Example 1

[0019] like Figure 1 As shown, a high boiling depth separation device comprises a distillation tower 5, the top of the distillation tower 5 is connected to the condenser 2 via a gas phase pipeline 7, the rear end of the condenser 2 is connected to the reflux tank 3, the reflux tank 3 is connected to the cracking tank 1 via a cracking tank feed pipeline 8, and the cracking tank 1 is connected to the cracking tower 4; a high boiling material feed port 501 is provided in the middle of the distillation tower 5, and a reboiler 6 is connected to the lower part.

[0020] The reboiler 6 is provided with a steam inlet 601 at the top, a steam condensate outlet 602 at the bottom, and a gas phase pipeline 3 603 connected to the distillation tower 5 at the top.

[0021] The bottom of the distillation tower 5 is connected to the reboiler 6 via a liquid phase pipeline 503, and a residual liquid outlet 502 is also provided at the bottom of the distillation tower 5.

[0022] The reflux tank 3 is connected to the distillation tower 5 through a reflux pipe.

[0023] The top of the cracking kettle 1 is provided with a hydrogen chloride feed port 12, and the top is also provided with a gas phase pipeline 9 and a liquid phase pipeline 10 connected to the cracking tower 4.

[0024] The top of the cracking tower 4 is connected to a crude monomer extraction pipeline 11 .

[0025] The cracking kettle 1 is provided with a jacket outside.

[0026] Example 2

[0027] Using the apparatus described in Example 1, the process for producing methylchlorosilane is as follows:

[0028] Steam enters the shell side of the reboiler 6 through the steam inlet 601; high boiling materials enter the distillation tower 5 through the high boiling material feed port 501, the light components enter the condenser 2 through the gas phase pipe 17, and the heavy components enter the tube side of the reboiler 6 through the liquid phase pipe 1503 at the bottom of the distillation tower 5, and the steam and the high boiling materials exchange heat; the steam flows out of the reboiler 6 through the steam condensate outlet 602, and the vaporized high boiling materials enter the distillation tower 5 through the gas phase pipe 3 603, and then enter the condenser 2 through the gas phase pipe 17; the gas phase in the condenser 2 enters the reflux tank 3 after condensation, and a part of the liquid phase in the reflux tank 3 is passed through the cracking kettle feed pipe 8 The product enters the cracking kettle 1, and the other part is refluxed to the distillation tower 5 through the reflux pipe; the outer jacket of the cracking kettle 1 is passed with steam, and the catalyst N,N-dimethylaniline is loaded inside. Hydrogen chloride enters the cracking kettle 1 through the hydrogen chloride feed port 12, and hydrogen chloride reacts with the liquid high-boiling substances inside the cracking kettle 1 under the action of the catalyst to produce methylchlorosilane; the product enters the cracking tower 4 through the gas phase pipeline 2 9, and is preliminarily distilled by the cracking tower 4 to obtain gaseous crude methylchlorosilane, which flows to the subsequent separation and purification process through the crude monomer extraction pipeline 11; the liquid phase in the cracking tower 4 flows back to the cracking kettle 1 through the bottom liquid phase pipeline 2 10.

[0029] The high-boiling substances that are not involved in the reaction and are enriched in the distillation tower 5 are regularly discharged through the residual liquid outlet 502 at the bottom.

[0030] The cracking reactor 1 was continuously fed with materials, and the liquid level of the cracking reactor 1 was maintained at about 1500mm. The mass ratio of the catalyst N,N-dimethylaniline to the high-boiling substances was controlled at 1%, and the hydrogen chloride introduction rate was 30~40Nm³ / h for the reaction.

[0031] The cracking kettle 1 and the reboiler 6 are both heated by 10 kg of saturated steam. The temperature of the cracking kettle 1 is controlled at 120-155°C, and the temperature of the kettle of the distillation tower 5 is controlled at 130-160°C.

[0032] Through the nitrogen vent valve, the pressure of the cracking kettle 1 was controlled at 50 kPa, and the pressure at the top of the distillation tower 5 was controlled at 30 kPa.

Claims

1. A high boiling depth separation device, characterized in that, The invention comprises a distillation tower (5), wherein the top of the distillation tower (5) is connected to a condenser (2) via a gas phase pipeline (7), the rear end of the condenser (2) is connected to a reflux tank (3), the reflux tank (3) is connected to a cracking tank (1) via a cracking tank feed pipeline (8), and the cracking tank (1) is connected to the cracking tower (4); the middle of the distillation tower (5) is provided with a high-boiling material feed port (501), and the lower part is connected to a reboiler (6).

2. A high boiling depth separation device according to claim 1, characterized in that, The reboiler (6) is provided with a steam inlet (601) at the top, a steam condensate outlet (602) at the bottom, and a gas phase pipeline (603) at the top for connection with the distillation tower (5).

3. A high boiling depth separation device according to claim 1, characterized in that, The bottom of the distillation tower (5) is connected to the reboiler (6) via a liquid phase pipeline (503), and a residual liquid extraction port (502) is also provided at the bottom of the distillation tower (5).

4. A high boiling depth separation device according to claim 1, characterized in that, The reflux tank (3) is connected to the distillation tower (5) via a reflux pipeline.

5. A high boiling depth separation device according to claim 1, characterized in that, The top of the cracking kettle (1) is provided with a hydrogen chloride feed port (12), and the top is also provided with a second gas phase pipeline (9) and a second liquid phase pipeline (10) connected to the cracking tower (4).

6. A high boiling depth separation device according to claim 1, characterized in that, The top of the cracking tower (4) is connected to a crude monomer extraction pipeline (11).

7. A high boiling depth separation device according to claim 1, characterized in that: The cracking kettle (1) is provided with a jacket on the outside.

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