阅读说明：本技术 一种2-氯-5氯甲基吡啶精馏工艺 (Rectification process of 2-chloro-5-chloromethylpyridine ) 是由 吴振 于 2020-03-29 设计创作，主要内容包括：本发明2-氯-5氯甲基吡啶精馏工艺,包括CD-0200扑捉设备、JR-01恒温系统和自动化系统；本发明工艺设备和工艺流程具有更加可靠的控制精馏釜温度,能实现比原来的精馏工艺,JR-01恒温系统可使精馏釜温度可控制在±2℃,酸度控制≤0.3,传统工艺酸度控制在2～0.7之间,为企业带来可靠的产品。(The rectification process of the 2-chloro-5-chloromethylpyridine comprises a CD-0200 capture device, a JR-01 constant temperature system and an automatic system; the process equipment and the process flow of the invention have more reliable control of the temperature of the rectifying still, can realize the rectifying process than the original rectifying process, the JR-01 constant temperature system can control the temperature of the rectifying still to be +/-2 ℃, the acidity to be less than or equal to 0.3, and the acidity to be controlled to be between 2 and 0.7 in the traditional process, thereby bringing reliable products for enterprises.)

1. A rectification process of 2-chloro-5-chloromethylpyridine comprises a CD-0200 capture device, a JR-01 constant temperature system and an automatic system; the method is characterized in that: the method comprises the following steps:

step 1: CD-0200 capture device:

comprises a capture device (11), a rectifying still (12) and a heat-insulating layer (13); the heat insulation layer (13) is arranged on the outer side wall of the upper end of the rectifying kettle (12); meanwhile, liquid is prevented from flowing back into the rectifying still (12) to be rectified repeatedly, and byproducts of the product are prevented from being generated at high temperature for a long time;

step 2: JR-01 constant temperature system:

comprises a steam inlet (1), a hot water inlet (2), an atomizer nozzle (3), a calculating mixing plate (4), a cooling water inlet (5), a thermometer measuring (6), a pressure measuring (7), a safety valve (8), an outlet (9) and a constant temperature pipe (10); the steam inlet (1) is arranged at the left end of the thermostatic tube (10); the hot water inlet (2) is arranged at the upper end of the left end of the thermostatic tube (10); the atomizer nozzle (3) is fixedly arranged at the lower end of the hot water inlet (2) and is arranged in the constant temperature pipe (10); the three calculation mixing plates (4) are fixedly arranged on the inner wall of the thermostatic tube (10); the cooling water inlet (5) is arranged at the upper end of the constant temperature pipe (10) and is arranged on the right side of the calculation mixing plate (4); the thermometer measurement (6) is fixedly arranged at the upper end of the constant temperature pipe (10) and is arranged on the right side of the cooling water inlet (5); the pressure measurement (7) is fixedly arranged at the upper end of the constant temperature tube (10) and is arranged on the right side of the thermometer measurement (6); the safety valve (8) is fixedly arranged at the upper end of the thermostatic tube (10) and is arranged on the right side of the pressure measurement (7); the outlet (9) is arranged at the right end of the constant temperature pipe (10);

and step 3: an automation system:

1. starting a water ring vacuum recovery device, realizing vacuum pumping on a front distillation kettle and a rear distillation kettle through primary vacuum recovery and secondary vacuum recovery, wherein the vacuum reaches-99 KPa, simultaneously transferring 1000-3000L of materials into a distillation kettle (12), starting a motor for stirring, and opening steam regulating valves FV-01 and PV-01; the steam flow is automatically controlled according to a set value, when the temperature TE-05 of the jacket is higher than 100 ℃, the pressure PT-01 is automatically switched to control the TV-01 steam flow, and the PV-01 is closed, when the temperature of the rectifying still (12) is 110 ℃, the temperature TE-01 is automatically switched to control valves TV-01 and TV-02, and the temperature is controlled to be constant at 125 ℃ until the rectification is finished;

2. and (3) discharging the kettle residue, turning off TV-01, TV-02, LV-01, PV-01 and a vacuum unit when the temperature is reduced, simultaneously turning on HV-01 and HV-02 for cooling, turning off HV-01 and HV-02 when the temperature TE-02 of the rectifying kettle (12) is lower than 80 ℃, simultaneously turning on PV-01 and LV-01 nitrogen switch valves HV-04, automatically returning the liquid level to normal, and finishing discharging the kettle residue. Waiting for the next batch of materials to be transferred, and operating the same as the above;

LT-01 liquid level PID control LV-01, LT-02 liquid level switching value control LV-02, LT-03 liquid level switching value control LV-03, TE-04 temperature switching value control TV-03, PT-03 pressure PID control P01;

4. when the temperature of the reaction kettle is higher than 135 ℃, the temperature rise rate is more than or equal to 5 ℃, and the pressure PT-02 is more than or equal to 10KPa, automatically closing TV-01 and TV-02, and opening HV-01 and HV-02;

5. when the pressure of the reaction kettle jacket is more than or equal to 400KPa, PV-01 is opened.

2. The rectification process of 2-chloro-5-chloromethylpyridine according to claim 1, wherein: the capture device (11) is arranged at the upper end of the rectifying still (12) and is mainly used for collecting the liquid state when the 2-chloro-5 chloromethylpyridine is in a small flow vaporization state.

3. The rectification process of 2-chloro-5-chloromethylpyridine according to claim 1, wherein: 6-8kg of steam is blown into the steam inlet (1).

4. The rectification process of 2-chloro-5-chloromethylpyridine according to claim 1, wherein: the hot water inlet (2) introduces 90-degree hot water.

5. The rectification process of 2-chloro-5-chloromethylpyridine according to claim 1, wherein: the design of the calculation mixing plate (4) is designed by taking an energy conservation law and a flow continuity law as reference.

6. The rectification process of 2-chloro-5-chloromethylpyridine according to claim 1, wherein: the JR-01 constant temperature system can directly control 0.6-0.8 MPa steam to rapidly heat the rectifying still (12); when the temperature of the rectifying still (12) rises to 110 ℃, the constant temperature device controls the constant temperature, and the inlet amount of hot water at 90 ℃ is calculated according to the heat balance principle, namely steam at 160 ℃ and hot water at 90 ℃; the condition that the output of the thermostatic device is required to be controlled at 125 ℃; controlling the ratio of the steam to the hot water to be 1: 0.781, and finishing the process at constant temperature for 6-8 hours; and closing the steam valve and the hot water valve, controlling the cooling water to enable the output temperature of the constant temperature device to be 30 ℃, and closing the cooling water when the temperature of the rectifying still (12) is reduced to 80 ℃.

Technical Field

The invention relates to the field of improvement of rectification process equipment, in particular to a rectification process of 2-chloro-5 chloromethyl pyridine.

Background

2-chloro-5-chloromethyl pyridine is an important pesticide and a medicine intermediate, is called CCMP for short, and is an important raw material for synthesizing efficient and low-toxicity pesticide imidacloprid, at present, the industrial production in China mostly adopts dicyclic cracking, and the dicyclic cracking is carried out, and then the dicyclic cracking is hydrolyzed, washed by alkali and washed by water and then enters a desolventizing section, the content of a CCMP crude product from the desolventizing section is only about 90 percent, and further rectification and extraction are needed; the traditional process has the defects of low rectification yield, large product loss in the rectification process and large toluene loss, but along with the continuous development of chemical enterprises and the improvement of product quality, the rectification process plays an important role in the chemical process, and a large number of chemical enterprises continuously improve the product yield; nowadays more and more chemical enterprises pay attention to the improvement of the process; the improvement of the product yield can help chemical enterprises to take the lead in the market and make better products. How to improve the quality of the rectification process becomes an effort direction of each chemical industry enterprise.

Disclosure of Invention

In view of the above situation, there is a need to provide a process that can solve the problems of low rectification yield, large product loss during rectification and large toluene loss in the prior art.

A rectification process of 2-chloro-5-chloromethylpyridine comprises a CD-0200 capture device, a JR-01 constant temperature system and an automatic system; the method comprises the following steps:

step 1: CD-0200 capture device:

comprises a capture device, a rectifying still and a heat-insulating layer; the heat insulation layer is arranged on the outer side wall of the upper end of the rectifying kettle; liquid is prevented from flowing back into the rectifying still to be rectified repeatedly, and byproducts are prevented from being generated in the product at high temperature for a long time;

step 2: JR-01 constant temperature system:

the system comprises a steam inlet, a hot water inlet, an atomizer nozzle, a calculation mixing plate, a cooling water inlet, thermometer measurement, pressure measurement, a safety valve, an outlet and a constant temperature pipe; the steam inlet is arranged at the left end of the constant temperature pipe; the hot water inlet is arranged at the upper end of the left end of the constant temperature pipe; the atomizer nozzle is fixedly arranged at the lower end of the hot water inlet and is arranged in the constant temperature pipe; the three calculation mixing plates are fixedly arranged on the inner wall of the thermostatic tube; the cooling water inlet is arranged at the upper end of the constant temperature pipe and is arranged on the right side of the calculation mixing plate; the thermometer is fixedly arranged at the upper end of the constant temperature pipe in a measuring way and is arranged on the right side of the cooling water inlet; the pressure measurement 7 is fixedly arranged at the upper end of the constant temperature tube and is arranged on the right side of the thermometer for measurement; the safety valve is fixedly arranged at the upper end of the constant temperature pipe and is arranged on the right side of the pressure measurement; the outlet is arranged at the right end of the constant temperature pipe;

and step 3: an automation system:

1. starting a water ring vacuum recovery device, realizing vacuum pumping on a front distillation kettle and a rear distillation kettle through primary vacuum recovery and secondary vacuum recovery, wherein the vacuum reaches-99 KPa, simultaneously transferring 1000-3000L of materials into the distillation kettle, starting a motor for stirring, and opening steam regulating valves FV-01 and PV-01; the steam flow is automatically controlled according to a set value, when the temperature TE-05 of a jacket is higher than 100 ℃, the pressure PT-01 is automatically switched to control the TV-01 steam flow, and the PV-01 is closed, when the temperature of a rectifying still is 110 ℃, the temperature TE-01 is automatically switched to control valves TV-01 and TV-02, and the temperature is controlled to be constant at 125 ℃ until the rectification is finished;

2. and (3) discharging the kettle residue, turning off TV-01, TV-02, LV-01, PV-01 and a vacuum unit when the temperature is reduced, simultaneously turning on HV-01 and HV-02 for cooling, turning off HV-01 and HV-02 when the temperature TE-02 of the rectifying kettle is lower than 80 ℃, simultaneously turning on PV-01 and LV-01 nitrogen switch valves HV-04, automatically returning the liquid level to normal, and finishing discharging the kettle residue. Waiting for the next batch of materials to be transferred, and operating the same as the above;

LT-01 liquid level PID control LV-01, LT-02 liquid level switching value control LV-02, LT-03 liquid level switching value control LV-03, TE-04 temperature switching value control TV-03, PT-03 pressure PID control P01;

4. when the temperature of the reaction kettle is higher than 135 ℃, the temperature rise rate is more than or equal to 5 ℃, and the pressure PT-02 is more than or equal to 10KPa, automatically closing TV-01 and TV-02, and opening HV-01 and HV-02;

5. when the pressure of the reaction kettle jacket is more than or equal to 400KPa, PV-01 is opened.

As a further scheme of the invention: the capture device is arranged at the upper end of the rectifying still and is mainly used for collecting the liquid state when the 2-chloro-5 chloromethyl pyridine is in a small flow vaporization state.

As a further scheme of the invention: 6-8kg of steam is blown into the steam inlet.

As a further scheme of the invention: the hot water inlet introduces 90-degree hot water.

As a further scheme of the invention: the design of the calculation mixing plate is designed by taking an energy conservation law and a flow continuity law as reference.

As a further scheme of the invention: the JR-01 constant temperature system can directly control 0.6-0.8 MPa steam to rapidly heat the rectifying still; when the temperature of the rectifying still rises to 110 ℃, the constant temperature device controls the constant temperature, and the inlet amount of 90-degree hot water, namely 160-degree steam and 90-degree hot water, is calculated according to the heat balance principle; the condition that the output of the thermostatic device is required to be controlled at 125 ℃; controlling the ratio of the steam to the hot water to be 1: 0.781, and finishing the process at constant temperature for 6-8 hours; and closing the steam valve and the hot water valve, controlling the cooling water to enable the output temperature of the constant temperature device to be 30 ℃, and closing the cooling water when the temperature of the rectifying still is reduced to 80 ℃.

Compared with the prior art, the invention has the beneficial effects that:

the process equipment and the process flow of the invention have more reliable control of the temperature of the rectifying still, can realize the rectifying process than the original rectifying process, the JR-01 constant temperature system can control the temperature of the rectifying still to be +/-2 ℃, the acidity to be less than or equal to 0.3, and the acidity to be controlled to be between 2 and 0.7 in the traditional process, thereby bringing reliable products for enterprises.

Drawings

FIG. 1 is a process flow diagram of an embodiment of the invention;

FIG. 2 is an enlarged view at A in the example of the present invention;

FIG. 3 is an enlarged view at B in the embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a JR-01 constant temperature system in an embodiment of the present invention;

FIG. 5 is a schematic diagram of a CD-0200 capture device in accordance with an embodiment of the invention;

in the figure: 1-6-8kg of steam inlet, 2-90 ℃ hot water inlet, 3-atomizer nozzle, 4-calculation mixing plate, 5-cooling water inlet, 6-thermometer measurement, 7-pressure measurement, 8-safety valve, 9-outlet, 10-constant temperature tube, 11-capture device, 12-rectifying still and 13-insulating layer.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the rectification process of 2-chloro-5-chloromethylpyridine according to the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 1-5, a rectification process of 2-chloro-5 chloromethylpyridine according to an embodiment of the present invention includes a CD-0200 capture device, a JR-01 constant temperature system, and an automation system; the method comprises the following steps:

step 1: CD-0200 capture device:

comprises a capture device 11, a rectifying still 12 and a heat-insulating layer 13; the capture device 11 is arranged at the upper end of the rectifying still 12 and is mainly used for collecting liquid when the 2-chloro-5-chloromethylpyridine is in a small-flow vaporization state; the heat insulation layer 13 is arranged on the outer side wall of the upper end of the rectifying kettle 12; liquid is prevented from flowing back into the rectifying still 12 to be rectified repeatedly, and byproducts are prevented from being generated in the product at high temperature for a long time;

step 2: JR-01 constant temperature system:

the system comprises a steam inlet 1, a hot water inlet 2, an atomizer nozzle 3, a calculation mixing plate 4, a cooling water inlet 5, a thermometer measurement 6, a pressure measurement 7, a safety valve 8, an outlet 9 and a constant temperature tube 10; the steam inlet 1 is arranged at the left end of the thermostatic tube 10, and 6-8kg of steam is blown into the steam inlet 1; the hot water inlet 2 is arranged at the upper end of the left end of the constant temperature pipe 10, and 90-degree hot water is introduced into the hot water inlet 2; the atomizer nozzle 3 is fixedly arranged at the lower end of the hot water inlet 2 and is arranged in the constant temperature pipe 10; the three calculation mixing plates 4 are fixedly arranged on the inner wall of the thermostatic tube 10, and the design of the calculation mixing plates 4 is designed by taking an energy conservation law and a flow continuity law as references; the cooling water inlet 5 is arranged at the upper end of the constant temperature pipe 10 and is arranged at the right side of the calculation mixing plate 4; the thermometer measurement 6 is fixedly arranged at the upper end of the constant temperature pipe 10 and is arranged on the right side of the cooling water inlet 5; the pressure measurement 7 is fixedly arranged at the upper end of the constant temperature tube 10 and is arranged on the right side of the thermometer measurement 6; the safety valve 8 is fixedly arranged at the upper end of the constant temperature pipe 10 and is arranged on the right side of the pressure measurement 7; the outlet 9 is arranged at the right end of the constant temperature pipe 10; the JR-01 constant temperature system can directly control 0.6-0.8 MPa steam to rapidly heat the rectifying still 12; when the temperature of the rectifying still 12 rises to 110 ℃, the constant temperature device controls the constant temperature, and the inlet amount of hot water at 90 ℃ is calculated according to the heat balance principle, namely the steam at 160 ℃ and the hot water at 90 ℃; the condition that the output of the thermostatic device is required to be controlled at 125 ℃; controlling the ratio of the steam to the hot water to be 1: 0.781, and finishing the process at constant temperature for 6-8 hours; closing the steam valve and the hot water valve, controlling the cooling water to enable the output temperature of the constant temperature device to be 30 ℃, and closing the cooling water when the temperature of the rectifying still 12 is reduced to 80 ℃;

and step 3: an automation system:

1. starting a water ring vacuum recovery device, realizing vacuum pumping on a front distillation kettle and a rear distillation kettle through primary vacuum recovery and secondary vacuum recovery, wherein the vacuum reaches-99 KPa, simultaneously transferring 1000-3000L of materials into the distillation kettle, starting a motor for stirring, and opening steam regulating valves FV-01 and PV-01; the steam flow is automatically controlled according to a set value, when the temperature TE-05 of a jacket is higher than 100 ℃, the pressure PT-01 is automatically switched to control the TV-01 steam flow, and the PV-01 is closed, when the temperature of a rectifying still 12 is 110 ℃, the temperature TE-01 is automatically switched to control valves TV-01 and TV-02, and the temperature is controlled to be constant at 125 ℃ until the rectification is finished;

2. and (3) discharging the kettle residue, turning off TV-01, TV-02, LV-01, PV-01 and a vacuum unit when the temperature is reduced, simultaneously turning on HV-01 and HV-02 for cooling, turning off HV-01 and HV-02 when the temperature TE-02 of the rectifying kettle 12 is lower than 80 ℃, simultaneously turning on PV-01 and LV-01 nitrogen switch valves HV-04, automatically returning the liquid level to normal, and finishing discharging the kettle residue. Waiting for the next batch of materials to be transferred, and operating the same as the above;

LT-01 liquid level PID control LV-01, LT-02 liquid level switching value control LV-02, LT-03 liquid level switching value control LV-03, TE-04 temperature switching value control TV-03, PT-03 pressure PID control P01;

4. when the temperature of the reaction kettle is higher than 135 ℃, the temperature rise rate is more than or equal to 5 ℃, and the pressure PT-02 is more than or equal to 10KPa, automatically closing TV-01 and TV-02, and opening HV-01 and HV-02;

5. when the pressure of the reaction kettle jacket is more than or equal to 400KPa, PV-01 is opened.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.