A method and device for adjusting reflux ratio to improve distillation purity

Abstract

The present invention relates to the technical field of chemical distillation equipment, and specifically to a method and device for adjusting the reflux ratio to improve the distillation purity, the method comprising the following steps: determining the full reflux position and the full extraction position of a liquid separation module; setting an initial position, and deflecting the liquid separation module to the initial position; collecting distillate and analyzing the purity of the distillate; determining the deflection direction of the liquid separation module according to the size comparison between the obtained purity and the set purity; and adjusting the liquid separation module to deflect toward the determined deflection direction; until the measurement position when the purity of the distillate reaches the maximum is screened out; according to the screened measurement position, the treated liquid is subjected to distillation treatment to improve the distillation purity of the treated liquid. The present invention can realize the multi-point adjustment of the swing position of the liquid separation module between full reflux or full extraction through the mutual cooperation of each unit, so as to accurately control the reflux ratio and improve the distillation purity.

Description

Technical Field

[0001] The invention relates to the technical field of chemical distillation equipment, and in particular to a method and a device for adjusting a reflux ratio to improve distillation purity. Background Art

[0002] Intermittent distillation, also known as batch distillation, is widely used in the fields of fine chemicals and pharmaceutical production. It is mainly used for batch distillation of liquid feeds. The difference from the continuous distillation device is that the bottom of the intermittent distillation device has a relatively large distillation tower and distillation kettle, and the tower body of the distillation tower has no stripping section. At the beginning of the intermittent distillation operation, all the materials are added to the distillation kettle, and then gradually heated and vaporized. After the drawn steam is condensed, part of it is used as the distillate product, and the other part is sent back to the kettle as reflux, and then the next batch of distillation operations is carried out.

[0003] Intermittent distillation is a non-steady-state process, which means that the reflux ratio needs to be continuously changed during the distillation process, so that the material composition in the distillation kettle is continuously reduced. If the reflux ratio is kept unchanged during operation, the composition of the distillate will decrease accordingly; conversely, in order to keep the composition of the distillate unchanged, the reflux ratio should be continuously increased during the distillation process. In order to meet the predetermined requirements, the actual operation can be flexible and diverse. For example, in the early stage of operation, the reflux ratio can be gradually increased to maintain the composition of the distillate roughly constant; but if the reflux ratio is too large, the distillation time is too long, the energy consumption is large, and the cost is high, which is not economically reasonable. Therefore, the reflux ratio can be kept unchanged in the later stage of operation. If the distillate obtained does not meet the requirements, this part of the product can be incorporated into the next batch of raw materials for distillation again. In the entire process of distillation separation, the reflux ratio is an important parameter for distillation design and operation, and the reflux ratio has an important influence on the product purity and product yield in the distillation operation.

[0004] At present, the batch distillation equipment generally adopts the distillation reflux ratio controller to control the reflux and extraction ratio. For example, the reflux ratio control structure of the standard distillation device 5225 is mainly composed of a distillation head with a magnet funnel and a reflux ratio controller with an electromagnet. The distillation reflux ratio controller is composed of an actuator and a control circuit. According to the requirements of the distillation process, the reflux and extraction ratios are determined, and the time of the time relay in the control circuit is adjusted accordingly, so as to control the on and off of the electromagnetic coil to make the magnet funnel swing back and forth between the full reflux and full extraction positions, so that full reflux and full extraction can be alternately performed within the time set by the reflux ratio controller.

[0005] The current intermittent distillation equipment mainly controls the swing position of the magnet funnel in the set time period during the distillation process, that is, the full reflux position and the full extraction position. When the magnet funnel swings to the full reflux position, full reflux is achieved. At this time, the reflux ratio is too large, the distillation time is too long, the energy consumption is large, the cost is high, and it is economically unreasonable; when the magnet funnel swings to the full extraction position, full extraction is achieved. At this time, the reflux ratio is too small, the separation of the liquid components is not complete, the product purity is not high, and it is easy to break the material balance and temperature balance in the reactor. Summary of the invention

[0006] In order to solve the problem that the existing intermittent distillation method needs to constantly change the power on and off time to change the reflux ratio, resulting in cumbersome operation, high time consumption, low efficiency and low product purity, the purpose of the present invention is to provide a distillation multi-point reflux ratio control device and method.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows.

[0008] A first aspect of the present invention provides a method for adjusting the reflux ratio to improve distillation purity, comprising the following steps:

[0009] Determine the full reflux position and the full extraction position of the liquid separation module; set the middle position between the full reflux position and the full extraction position as the initial position, and deflect the liquid separation module to the initial position;

[0010] Collecting distillate and analyzing the purity of the distillate; determining the deflection direction and deflection position of the liquid separation module according to the comparison between the obtained purity and the set purity; and adjusting the liquid separation module to deflect toward the determined deflection direction and deflection position; repeating the operation multiple times until the measurement position at which the purity of the distillate reaches the maximum is screened out;

[0011] According to the screened measurement positions, the liquid to be treated is distilled to improve the distillation purity of the liquid to be treated.

[0012] In a preferred embodiment, the total reflux position is a configuration position of a liquid separation module for achieving total reflux of the distillate; the total extraction position is a configuration position of a liquid separation module for achieving total extraction of the distillate.

[0013] In a preferred embodiment, the set purity is the purity of the distillate that meets the qualified extraction standard. Preferably, the set purity is 85% to 90%.

[0014] In a preferred embodiment, the specific conditions for determining the deflection direction and deflection position of the liquid separation module are:

[0015] When the purity of the distillate is less than the set purity, the liquid separation module is adjusted to deflect toward the direction of the total reflux position to a position between the measuring position and the total reflux position; or,

[0016] When the purity of the distillate is greater than or equal to the set purity, the liquid separation module is adjusted to deflect toward the direction of the full extraction position to a middle position between the measuring position and the full extraction position.

[0017] In a preferred embodiment, the liquid separation module is adjusted to deflect toward a determined deflection direction and deflection position, specifically:

[0018] When the determined deflection direction is toward the full reflux position, the liquid dispensing module is adjusted to deflect toward the middle position between the measuring position and the full reflux position, or,

[0019] When the determined deflection direction is toward the full extraction position, the liquid separation module is adjusted to deflect toward a middle position between the measuring position and the full extraction position.

[0020] In a preferred embodiment, the measuring position is a configuration position of a liquid separation module for collecting distillate, and is configured between the total reflux position and the total extraction position.

[0021] In a preferred embodiment, the liquid separation module is adjusted to deflect toward a determined deflection direction by using a reflux ratio control system; the reflux ratio control system includes:

[0022] A permanent magnet unit is arranged on the outer wall surface of the liquid separation module;

[0023] An electromagnet module, disposed on one side of the permanent magnet unit and magnetically coupled to the permanent magnet unit;

[0024] The power supply module comprises an adjustable DC regulated power supply and a power supply polarity conversion switch; the electromagnet module is sequentially connected to the power supply polarity conversion switch and the adjustable DC regulated power supply;

[0025] By adjusting the output current of the adjustable DC regulated power supply, the magnitude of the magnetic attraction or repulsion of the electromagnet module on the permanent magnet unit is changed, so as to adjust the offset spacing or offset angle of the liquid separation module;

[0026] The current direction of the electromagnet module is adjusted by the power polarity conversion switch to change the direction of the magnetic attraction of the electromagnet module to the permanent magnet unit, so as to adjust the deflection direction of the liquid separation module.

[0027] In a preferred embodiment, the reflux ratio control system further comprises a processing module; the processing module is electrically connected to the adjustable DC regulated power supply and the power polarity conversion switch respectively;

[0028] The processing module can determine the deflection direction and deflection displacement of the liquid separation module according to the comparison result of the obtained distillate purity and the set purity; then control the power polarity conversion switch to adjust the current direction of the electromagnet module according to the determined deflection direction of the liquid separation module; and control the output current size of the adjustable DC regulated power supply according to the determined deflection displacement of the liquid separation module.

[0029] The second aspect of the present invention provides a device for adjusting the reflux ratio to improve the distillation purity. The method for adjusting the reflux ratio to improve the distillation purity described in the first aspect is performed using the device described in the second aspect. The device includes a distillation device, a liquid separation module and a reflux ratio control system. The reflux ratio control system includes:

[0030] A permanent magnet unit is arranged on the outer wall surface of the liquid separation module;

[0031] An electromagnet module, disposed on one side of the permanent magnet unit and magnetically coupled to the permanent magnet unit;

[0032] The power supply module comprises an adjustable DC regulated power supply and a power supply polarity conversion switch; the electromagnet module is sequentially connected to the power supply polarity conversion switch and the adjustable DC regulated power supply;

[0033] By adjusting the output current of the adjustable DC regulated power supply, the magnitude of the magnetic attraction or repulsion of the electromagnet module on the permanent magnet unit is changed, so as to adjust the offset spacing or offset angle of the liquid separation module;

[0034] The current direction of the electromagnet module is adjusted by the power polarity conversion switch to change the direction of the magnetic attraction of the electromagnet module to the permanent magnet unit, so as to adjust the deflection direction of the liquid separation module.

[0035] In a preferred embodiment, the reflux ratio control system further comprises a processing module; the processing module is electrically connected to the adjustable DC regulated power supply and the power polarity conversion switch respectively;

[0036] The processing module can determine the deflection direction and deflection displacement of the liquid separation module according to the comparison result of the obtained distillate purity and the set purity; then control the power polarity conversion switch to adjust the current direction of the electromagnet module according to the determined deflection direction of the liquid separation module; and control the output current size of the adjustable DC regulated power supply according to the determined deflection displacement of the liquid separation module.

[0037] In a preferred embodiment, the distillation device includes a distillation reactor, a distillation column and a condensation module, one end of the distillation column is inserted into the top of the distillation reactor, the other end of the distillation column has a distillate outlet and a reflux liquid inlet, and the condensation module has a distillate inlet, a reflux liquid outlet and a produced liquid outlet; the distillate outlet of the distillation column is connected to the distillate inlet of the condensation module through a distillate pipeline; the reflux liquid outlet of the condensation module is connected to the reflux liquid inlet of the distillation column through a reflux liquid pipeline, and the produced liquid outlet of the condensation module is connected to the produced liquid container through a produced liquid pipeline. In a preferred embodiment, the condensation module is a condenser.

[0038] In a preferred embodiment, the condensation module has a partition layer therein, a condensate outlet is extended downward from the partition layer, and the liquid separation module is arranged at the lower side of the condensate outlet.

[0039] In a preferred embodiment, the liquid separation module has a first opening and a second opening, the size of the first opening is larger than the size of the second opening, and the first opening is arranged at the lower side of the condensate outlet and corresponds to the position of the condensate outlet to facilitate the collection of the distillate flowing out of the condensate outlet.

[0040] In a preferred embodiment, a produced liquid collecting assembly is installed in the condensation module, and the produced liquid collecting assembly has a first port and a second port, the size of the first port is larger than the size of the second port, and the second port is inserted in the produced liquid pipeline along the produced liquid outlet; the opening direction of the first port is toward the second opening of the liquid separation module, so as to collect the distillate flowing out of the second opening of the liquid separation module.

[0041] Beneficial effects of the present invention:

[0042] 1. The present invention accurately adjusts the swing position of the liquid separation module and compares the purity of the corresponding measurement position to select the measurement position when the purity of the distillate is the maximum as the optimal reflux ratio position; and performs distillation treatment at this position to improve the distillation purity of the liquid to be treated. The method of the present invention can directly perform distillation treatment on the corresponding liquid to be treated at the determined optimal split ratio position, thereby improving the distillation efficiency and increasing the purity of the distillate to more than 98.5%.

[0043] 2. The present invention can realize multi-point adjustment of the swing position of the liquid separation module between full reflux or full extraction through the mutual cooperation of various units such as the power module and the processing module, so as to accurately control the reflux ratio.

[0044] 3. The present invention provides a DC regulated power supply to the electromagnet module through a power module to control the magnetic attraction of the DC electromagnet coil, thereby achieving the purpose of swinging the triangular magnet funnel to the optimal reflux ratio position. The method of the present invention meets various process requirements of distillation and purification, and can significantly shorten the distillation and purification time, save costs, have high product purity, and maintain stable working conditions for a long time. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 A process flow chart for adjusting the reflux ratio to improve distillation purity is provided in one embodiment of the present invention.

[0046] Figure 2 This is a connection diagram of various units such as a power module and a processing module provided in one embodiment of the present invention.

[0047] Figure 3 A schematic structural diagram of an intermittent distillation device provided in one embodiment of the present invention.

[0048] Figure 4 for Figure 3 A partial enlarged schematic diagram of part A.

[0049] Figure 5 It is a schematic diagram of the structure of an existing intermittent distillation device.

[0050] In the figure, 110, distillation kettle; 111, distillation tower; 112, condenser; 113, produced liquid collector; 114, temperature sensor; 115, separating funnel; 116, magnet; 117, coil electromagnet; 118, time relay; 119, power supply;

[0051] 210. Distillation reactor; 211. Distillation column; 212. Condensation module; 213. Produced liquid container; 214. Temperature sensing unit; 215. Liquid separation module; 216. Permanent magnet unit; 217. Electromagnet module; 218. Power polarity conversion switch; 219. Adjustable DC regulated power supply. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0053] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0054] In the following embodiments, the reflux ratio is the ratio R of the reflux liquid flow rate returned from the top of the distillation tower to the produced liquid flow rate during intermittent distillation operation, that is, R=L / D, where R is the reflux ratio, L is the reflux liquid flow rate, and D is the produced liquid flow rate. The reflux liquid is returned to the distillation tower for further distillation, and the produced liquid is the product flowing out of the distillation tower.

[0055] Intermittent distillation is a non-steady-state process, which means that the reflux ratio needs to be continuously changed during the distillation process, so that the material composition in the distillation kettle is continuously reduced. If the reflux ratio is kept unchanged during operation, the composition of the distillate will decrease accordingly; conversely, in order to keep the composition of the distillate unchanged, the reflux ratio should be continuously increased during the distillation process. In order to meet the predetermined requirements, the actual operation can be flexible and diverse. For example, in the early stage of operation, the reflux ratio can be gradually increased to maintain the composition of the distillate roughly constant; but if the reflux ratio is too large, the distillation time is too long, the energy consumption is large, and the cost is high, which is not economically reasonable. Therefore, the reflux ratio can be kept unchanged in the later stage of operation. If the distillate obtained does not meet the requirements, this part of the product can be incorporated into the next batch of raw materials for distillation again. In the entire process of distillation separation, the reflux ratio is an important parameter for distillation design and operation, and the reflux ratio has an important influence on the product purity and product yield in the distillation operation.

[0056] In a chemical reaction, a reactor is connected through a distillation-condensation structure, and a movable funnel with a magnet is provided in the condenser. By controlling the reciprocating swing of the funnel with the magnet, full reflux and full recovery of the condensed liquid can be achieved, and by controlling the ratio of full reflux and full recovery, the purity of the reaction can be improved. However, how to control the swing position and frequency of the funnel with the magnet to achieve precise control of the reflux and recovery ratio is a difficult problem that needs to be solved urgently.

[0057] At present, the commonly used intermittent distillation device mainly uses the distillation reflux ratio controller to control the reflux and production ratio. For example, the reflux ratio control structure of the standard distillation device 5225 is mainly composed of a distillation head with a magnet funnel and a reflux ratio controller with an electromagnet. The distillation reflux ratio controller is composed of an actuator and a control circuit. According to the requirements of the distillation process, the reflux and production ratios are determined, and the time of the time relay in the control circuit is adjusted accordingly, so as to control the on and off of the electromagnetic coil to make the magnet funnel swing back and forth between the full reflux and full production positions, so that full reflux and full production can be alternately carried out within the time set by the reflux ratio controller.

[0058] However, the existing reflux ratio control structure can only control the swing position of the magnet funnel in a set time period, that is, the full reflux position and the full extraction position. When the magnet funnel swings to the full reflux position, full reflux is achieved. At this time, the reflux ratio is too large, the distillation time is too long, the energy consumption is large, the cost is high, and it is economically unreasonable; when the magnet funnel swings to the full extraction position, full extraction is achieved. At this time, the reflux ratio is too small, the separation of the liquid components is not complete, the product purity is not high, and it is easy to break the material balance and temperature balance in the reactor.

[0059] The current reflux ratio control structure can only achieve full reflux and full extraction, but cannot achieve smooth multi-point adjustment of the swing position of the magnet funnel between the full reflux position and the full extraction position to accurately control the reflux ratio. In addition, in order to obtain the best reflux ratio, the operator needs to frequently go to the top of the device to observe and adjust the position of the magnet funnel, which is time-consuming and labor-intensive, and prone to misoperation.

[0060] Comparative Example 1

[0061] like Figure 5 The intermittent distillation device currently used in the prior art includes a distillation structure, a separating funnel 115 and a reflux ratio control structure, wherein the distillation structure includes a distillation kettle 110, a distillation tower 111 and a condenser 112, one end of the distillation tower 111 is connected to the distillation kettle 110, the distillation tower 111 has a steam outlet and a reflux liquid inlet, the condenser 112 has a steam inlet, a reflux liquid outlet and a produced liquid outlet, the steam outlet of the distillation tower 111 is connected to the steam inlet of the condenser 112 through a pipeline, the reflux liquid outlet of the condenser 112 is connected to the reflux liquid inlet of the distillation tower 111 through a pipeline, and the produced liquid outlet of the condenser 112 is connected to the produced liquid collector 113 through a pipeline. Usually, a temperature sensor 114 is also installed at the top of the distillation tower 111 to detect the temperature of the steam outlet. Of course, the temperature sensor can be replaced by a thermometer in a small distillation tower.

[0062] A clamping ring is fixedly installed at the bottom of the condenser 112, and the clamping ring is located on the upper side of the reflux liquid outlet and the produced liquid outlet, and the separating funnel 115 is plugged into the clamping ring so that the separating funnel can swing back and forth. Of course, the separating funnel 115 can also be installed at one end of the clamping ring, and the separating funnel 115 and the clamping ring are rotatably connected, so that the separating funnel 115 can swing back and forth within the vertical plane.

[0063] The reflux ratio control structure includes a magnet 116, a coil electromagnet 117, a time relay 118 and a power supply 119. The magnet 116 is installed on the outer wall of the lower end of the separatory funnel 115. The magnet 116 can be a magnet block or a magnet ring. The coil electromagnet 117 is installed on the outer wall of the condenser 112 and corresponds to the position of the magnet 116, so as to control the movement of the magnet 116 approaching or moving away by turning on and off the current of the coil electromagnet 117. The coil electromagnet 117 is connected to the time relay 118 and the power supply 119 in turn, and the time relay 118 is used to control the time of turning on and off the power supply 119 and the coil electromagnet 117.

[0064] For example, Figure 5 , the time relay 118 and the power supply 119 are integrated into one controller. Two display screens and two indicator lights are arranged on the front side of the controller. The two display screens are respectively a power-on display screen and a power-off display screen, and the two indicator lights are respectively a power-on indicator light and a power-off indicator light. When the power is on, the power-on indicator light is on, and the power-on display screen starts timing; when the power is off, the power-off indicator light is on, and the power-off display screen starts timing. When the power supply 119 and the coil electromagnet 117 are energized for 10s through the time relay 118, the coil electromagnet 117 generates an attraction force, swings the lower end of the separating funnel 115 and sucks it in the direction of the coil electromagnet 117, and the liquid moves to the full extraction channel. When the power supply 119 and the coil electromagnet 117 are de-energized for 3s through the time relay 118, the coil electromagnet 117 loses the attraction force on the magnet 116 due to the power off, and the separating funnel 115 returns to its original position due to its own gravity, and the liquid moves to the full reflux channel. Therefore, the existing reflux ratio control structure can only realize the back and forth swing of the positions of full reflux and full extraction, so that full reflux and full extraction can be alternately performed within the time period set by the time relay 118.

[0065] However, the existing reflux ratio control structure can only control the separating funnel 115 to swing along the two positions of the full reflux position and the full extraction position in a set time period. When the separating funnel 115 swings to the full reflux position, full reflux is achieved. At this time, the reflux ratio is too large, the distillation time is too long, the energy consumption is large, the cost is high, and it is economically unreasonable; when the separating funnel swings to the full extraction position, full extraction is achieved. At this time, the reflux ratio is too small, the separation of the liquid components is not thorough, the product purity is not high, and it is easy to break the material balance and temperature balance in the distillation kettle. Since the reflux ratio control structure of the existing intermittent distillation structure can only realize the reciprocating swing of the two positions of full reflux or full extraction, there is randomness in the control of product purity, and the purity of the product cannot be accurately controlled. Moreover, the purity of the distillation product obtained by the existing method is still not high, and the product value is relatively low. In addition, in order to obtain the optimal reflux ratio, the operator needs to frequently go to the top of the device to observe and adjust the position of the separating funnel, which is time-consuming and labor-intensive, and prone to misoperation.

[0066] In order to solve the above technical problems, the following embodiments of the present invention mainly improve the reflux ratio control structure, and use an adjustable DC voltage-stabilized power supply in conjunction with an electromagnet module to achieve multi-point adjustment of the separatory funnel between full reflux and full extraction smoothly, thereby screening out the measurement position when the purity of the distillate reaches the maximum, so as to achieve the purpose of accurately controlling the reflux ratio to obtain a high-purity product and improve the separation efficiency. In addition, the present invention improves the distillation method, and judges the deflection direction of the separatory funnel according to the purity of the distillate, and circulates in this way to screen out the swing position of the separatory funnel when the purity of the distillate is the maximum, thereby determining the optimal reflux ratio.

[0067] In addition, since the distillation structures of small and medium-sized chemical and pharmaceutical R&D experiments are at a certain height from the ground, in order to obtain the best reflux ratio, operators need to frequently go to the top of the device to observe and adjust the position of the magnet funnel, which is time-consuming, labor-intensive and unsafe. In order to solve this problem, the following embodiments of the present invention mainly install a camera and a display screen at the position of the distillation head, so that operators can achieve intuitive and safe visual operation on the ground, thereby improving the operation time efficiency and the operation safety.

[0068] The method and device for adjusting the reflux ratio to improve the distillation purity provided by the present invention are further described in detail below in conjunction with the embodiments and drawings.

[0069] Example 1

[0070] like Figure 3 On the one hand, the present invention provides a device for adjusting the reflux ratio to improve the distillation purity, including a distillation device, a liquid separation module 215 and a reflux ratio control device, wherein the reflux ratio control device includes: a permanent magnet unit 216, an electromagnet module 217, a power polarity conversion switch 218 and an adjustable DC regulated power supply 219.

[0071] The distillation device is basically the same as the distillation device of Comparative Example 1, such as Figure 3, the distillation device includes: a distillation reactor 210, a distillation column 211 and a condensation module 212. One end of the distillation column 211 is connected to the distillation reactor 210, for example, one end of the distillation column 211 is inserted at the top of the distillation reactor 210. The top of the distillation column 211 has a distillate outlet and a reflux inlet, the condensation module 212 has a distillate inlet, a reflux outlet and a produced liquid outlet, the steam outlet of the distillation column 211 is connected to the distillate inlet of the condensation module 212 through a distillation pipeline, the reflux outlet of the condensation module 212 is connected to the reflux inlet of the distillation column 211 through a reflux pipeline, and the produced liquid outlet of the condensation module 212 is connected to the produced liquid container 213 through a produced liquid pipeline. Usually, a temperature sensing unit 214 is also installed on the top of the distillation column 211 for detecting the temperature of the distillate outlet. Of course, the temperature sensing unit 214 can be a temperature sensor, and the temperature sensor can be replaced by a thermometer in a small distillation tower.

[0072] In a preferred embodiment, a partition layer is provided in the condensation module 212 , and a condensate outlet is extended downward from the partition layer. The liquid separation module 215 is disposed at the lower side of the condensate outlet.

[0073] In a preferred embodiment, the liquid separation module 215 has a first opening and a second opening, the size of the first opening is larger than the size of the second opening, and the first opening is arranged at the lower side of the condensate outlet and corresponds to the position of the condensate outlet to facilitate the collection of the distillate flowing out of the condensate outlet.

[0074] In a preferred embodiment, a produced liquid collecting assembly is installed in the condensation module 212, and the produced liquid collecting assembly has a first port and a second port. The size of the first port is larger than that of the second port, and the second port is inserted in the produced liquid pipeline along the produced liquid outlet; the opening direction of the first port is toward the second opening of the liquid separation module 215, so as to collect the distillate flowing out of the second opening of the liquid separation module 215.

[0075] In a preferred embodiment, in order to obtain the best reflux ratio, the operator needs to frequently go to the top of the device to observe and adjust the position of the liquid separation module, which is time-consuming, laborious and unsafe. Therefore, in order to solve the observation problem of the liquid separation module 215, the present invention is provided with a display device on one side of the condensation module 212 close to the liquid separation module 215 in one preferred embodiment, and the video information or photo information taken in real time by the display device is transmitted to the computer, and the operator can realize intuitive and safe visual operation on the ground through the computer. Preferably, the display device is a camera, which is connected to the computer, and the camera can capture the swinging image information of the liquid separation module 215 and transmit it to the computer in real time, and the display screen of the computer can display the received image information.

[0076] The liquid separation module 215 is rotatably installed in the condensation module 212, and is located near the reflux liquid outlet and the produced liquid outlet of the condensation module 212, so that the liquid separation module 215 can swing back and forth within the vertical plane. For example, the condensation module 212 is horizontally fixed with a support member near the reflux liquid outlet and the produced liquid outlet, and the side wall of the liquid separation module 215 is provided with a fixed ring, which is sleeved on the support member, and the fixed ring can rotate around the support member on the support member, thereby realizing a rotatable connection between the liquid separation module 215 and the condensation module 212 in the vertical plane direction. Of course, in other embodiments, other assembly relationships can also be used to realize a rotatable connection between the liquid separation module 215 and the condensation module 212 in the vertical plane direction. The rotatable connection belongs to the prior art in this field and will not be repeated here.

[0077] like Figure 2 and Figure 4 The reflux ratio control system is used to adjust the liquid separation module 215 to deflect toward a determined deflection direction. The reflux ratio control system includes: a permanent magnet unit 216, an electromagnet module 217, a power module and a processing module.

[0078] The permanent magnet unit 216 is disposed on the outer wall of the liquid separation module 215 ; according to the magnitude of the magnetic attraction or repulsion provided by the electromagnet module 217 , the permanent magnet unit 216 is used to drive the liquid separation module 215 to swing left or right within the vertical plane.

[0079] The electromagnet module 217 is disposed on one side of the permanent magnet unit 216 and is magnetically coupled to the permanent magnet unit 216. The electromagnet module 217 is used to provide a magnetic attraction force or a repulsive force to the electromagnet module 217 to adjust the swing direction and swing distance of the permanent magnet unit 216. The electromagnet module 217 is a DC electromagnet.

[0080] The power module includes an adjustable DC regulated power supply 219 and a power polarity conversion switch 218; the electromagnet module 217 is connected to the power polarity conversion switch 218 and the adjustable DC regulated power supply 219 in sequence; by adjusting the output current of the adjustable DC regulated power supply 219, the magnitude of the magnetic attraction or repulsion of the electromagnet module 217 on the permanent magnet unit 216 is changed, so as to adjust the offset spacing or offset angle of the liquid separation module 215; by adjusting the current direction of the electromagnet module 217 through the power polarity conversion switch 218, the direction of the magnetic attraction of the electromagnet module 217 on the permanent magnet unit 216 is changed, so as to adjust the deflection direction of the liquid separation module 215. Thus, the magnitude of the magnetic attraction or repulsion of the electromagnet module 217 on the electromagnet module 217 is adjusted through the control of the adjustable DC regulated power supply 219 and the power polarity conversion switch 218, so as to adjust the swing direction and swing distance of the permanent magnet unit 216.

[0081] It should be noted that the embodiment of the present invention provides an adjustable 0-24V power supply to the electromagnet module 217 through an adjustable DC regulated power supply 219. The higher the voltage provided by the adjustable DC regulated power supply 219, the greater the current intensity passing through the electromagnet module 217, and the stronger the electromagnetic attraction or repulsion of the electromagnet module 217. In this way, the magnetic attraction of the DC electromagnet coil of the electromagnet module 217 can be controlled by adjusting the output voltage of the adjustable DC regulated power supply 219, thereby achieving the purpose of swinging the liquid separation module 215 to the optimal reflux ratio position.

[0082] The reflux ratio control system also includes a processing module; the processing module is electrically connected to the adjustable DC regulated power supply 219 and the power polarity conversion switch 218 respectively; the processing module can determine the deflection direction and deflection displacement of the liquid separation module 215 according to the comparison result of the obtained purity of the distillate and the set purity; then control the power polarity conversion switch 218 to adjust the current direction of the electromagnet module 217 according to the determined deflection direction of the liquid separation module 215; and control the output current size of the adjustable DC regulated power supply 219 according to the determined deflection displacement of the liquid separation module 215. The specific process is:

[0083] The processing module first performs the purity of the distillate P x With the set purity P 设 The deflection direction and deflection displacement of the liquid separation module 215 are determined according to the comparison result of the obtained purity of the distillate and the set purity.

[0084] For example, when the purity of the distillate obtained is P x <Set Purity P 设 When the processing module obtains the comparison result, it is determined that the deflection direction of the liquid separation module 215 is deflected toward the full reflux position, and the deflection displacement is the middle position between the measurement position where the liquid separation module 215 is located and the full reflux position when measuring the purity of the distillate. Then, according to the determined deflection direction of the liquid separation module 215, the power polarity conversion switch 218 is controlled to adjust the current direction of the electromagnet module 217, so that the liquid separation module 215 swings toward the determined deflection direction and deflection position.

[0085] For example, when the purity of the distillate obtained is P x ≥Set purity P 设 When the processing module obtains the comparison result, it is determined that the deflection direction of the liquid separation module 215 is deflected toward the full extraction position, and the deflection displacement is the middle position between the measurement position where the liquid separation module 215 is located and the full extraction position when measuring the purity of the distillate. Then, according to the determined deflection direction of the liquid separation module 215, the power polarity conversion switch 218 is controlled to adjust the current direction of the electromagnet module 217, so that the liquid separation module 215 swings toward the determined deflection direction and deflection position.

[0086] The method for adjusting the reflux ratio to improve the distillation purity is further described below.

[0087] like Figure 1 and Figure 2 , a method for adjusting the reflux ratio to improve the distillation purity, comprising the following steps:

[0088] (1) Determine the full reflux position and the full extraction position of the liquid separation module; set the middle position between the full reflux position and the full extraction position as the initial position, deflect the liquid separation module to the initial position, and start collecting the distillate at the initial position.

[0089] In step (1), the total reflux position is the configuration position of the liquid separation module for achieving total reflux of the distillate; the total extraction position is the configuration position of the liquid separation module for achieving total extraction of the distillate.

[0090] (2) collecting the distillate and analyzing the purity of the distillate; determining the deflection direction and deflection position of the liquid separation module according to the comparison between the obtained purity and the set purity; and adjusting the liquid separation module to deflect toward the determined deflection direction and deflection position; repeating the operation multiple times until the measurement position at which the purity of the distillate reaches the maximum is screened out.

[0091] In step (2), the set purity is the purity of the distillate that meets the qualified extraction standard. Preferably, the set purity is 85% to 90%, such as 85%, 86%, 87%, 88%, 89%, 90%, etc. Of course, the specific set purity can also be determined according to actual needs.

[0092] The measuring position is a configuration position of a liquid separation module for collecting distillate, and is configured between the total reflux position and the total extraction position. The measuring position is determined according to a comparison result between the obtained purity and the set purity.

[0093] The specific conditions for determining the deflection direction and deflection position of the liquid separation module are: when the purity of the distillate is x <Set Purity P 设 When the liquid separation module is adjusted to deflect toward the direction of the total reflux position to the middle position between the measuring position and the total reflux position; or, when the purity P of the distillate is x ≥Set purity P 设 When the liquid separation module is adjusted to deflect toward the direction of the full extraction position to the middle position between the measuring position and the full extraction position.

[0094] The liquid separation module is adjusted to deflect toward a determined deflection direction and deflection position, specifically: when the determined deflection direction is toward the full reflux position, the liquid separation module is adjusted to deflect toward the middle position between the measuring position and the full reflux position, or, when the determined deflection direction is toward the full extraction position, the liquid separation module is adjusted to deflect toward the middle position between the measuring position and the full extraction position.

[0095] Then repeat step (2) several times until the measurement position where the purity of the distillate reaches the maximum is screened out. Specifically:

[0096] When the purity of the distillate is P x '<Set purity P 设 When the measuring position is set, the liquid separation module is adjusted to deflect toward the direction of the full reflux position to a middle position between the measuring position and the full reflux position.

[0097] When the purity of the distillate is P x '≥Set purity P 设 , and the purity of the distillate is P x '>The purity of the distillate measured in the previous step P x When the liquid separation module is adjusted to deflect toward the direction of the full extraction position to the middle position between the measuring position and the full extraction position.

[0098] When the purity of the distillate is P x '≥Set purity P 设 , and the purity of the distillate is P x '≈Purity of distillate measured in the previous step x , the measurement position here is determined to be the measurement position when the purity of the distillate reaches the maximum. The purity of the distillate P x '≈Purity of distillate measured in the previous step x , for example, P x =P x ±b, the value range of b is 0.1 to 0.5, for example, 0.1, 0.2, 0.3, 0.4, 0.5, etc.

[0099] In a preferred embodiment, the liquid separation module is adjusted to deflect toward a determined deflection direction, and a reflux ratio control system is used. The reflux ratio control system is the reflux ratio control system of Example 1. Through the mutual cooperation of various units such as the current control module and the microprocessor module, the swing position of the liquid separation module can be adjusted at multiple points between full reflux or full extraction to accurately control the reflux ratio.

[0100] (3) According to the selected measurement positions, the liquid to be treated is distilled to improve the distillation purity of the liquid to be treated.

[0101] The following is an example of the distillation operation of the waste acetone solution produced in daily production to further illustrate the above method.

[0102] In the following examples, the daily produced waste acetone solution mainly contains 75% acetone, 20% N-methylpyrrolidone and other impurities and high-boiling point wastes.

[0103] The method for adjusting the reflux ratio to improve the distillation purity comprises the following steps:

[0104] (1) Determine the full reflux position and the full extraction position of the liquid separation module; set the middle position between the full reflux position and the full extraction position as the initial position, deflect the liquid separation module to the initial position, and start collecting the distillate at the initial position.

[0105] (2) Collect the distillate and analyze its purity; compare the obtained purity with the set purity. The set purity is the purity of the distillate that meets the qualified extraction standard. Here, the set purity P is proposed. 设 The liquid separation module is adjusted to deflect in a certain deflection direction by using the reflux ratio control system of Example 1. Specifically:

[0106] When the purity of the distillate is P x <Set Purity P 设 When the measuring position is set, the liquid separation module is adjusted to deflect toward the direction of the full reflux position to a middle position between the measuring position and the full reflux position.

[0107] When the purity of the distillate is P x ≥Set purity P 设 When the liquid separation module is adjusted to deflect toward the direction of the full extraction position to the middle position between the measuring position and the full extraction position.

[0108] (3) Repeat step (2) for multiple times until the measurement position where the purity of the distillate reaches the maximum is screened out. Specifically:

[0109] When the purity of the distillate is P x '<Set purity P 设 When the measuring position is set, the liquid separation module is adjusted to deflect toward the direction of the full reflux position to a middle position between the measuring position and the full reflux position.

[0110] When the purity of the distillate is P x '≥Set purity P 设 , and the purity of the distillate is P x '>The purity of the distillate measured in the previous step P x When the liquid separation module is adjusted to deflect toward the direction of the full extraction position to the middle position between the measuring position and the full extraction position.

[0111] When the purity of the distillate is P x '≥Set purity P 设 , and the purity of the distillate is P x '≈Purity of distillate measured in the previous step x , the measurement position here is determined to be the measurement position when the purity of the distillate reaches the maximum. The purity of the distillate P x '≈Purity of distillate measured in the previous step x , for example, P x =P x ±b, the value range of b is 0.1~0.5, and b=0.3 is proposed here.

[0112] (4) According to the measurement positions selected in step (3), the reflux ratio of the determined measurement positions is 75 / 25, and the waste acetone solution is subjected to batch distillation treatment at the reflux ratio.

[0113] The purity of each batch of distillate after distillation is measured and tested. If the result is above 98.5%, the distillate (acetone) can be recycled and reused.

[0114] In summary, the embodiment of the present invention can realize the multi-point adjustment of the swing position of the liquid separation module between full reflux or full extraction through the mutual cooperation of various units such as the power module and the processing module, so as to accurately control the reflux ratio and quickly adjust it to the optimal reflux ratio. In the whole process of distillation separation, the method of the embodiment of the present invention can adjust the reflux ratio flexibly, smoothly and at multiple points. Rapidly and accurately adjusting the optimal reflux ratio is of great significance to the product purity, product yield and time cost in the distillation operation. Moreover, the method of the embodiment of the present invention meets various process requirements of distillation and purification, and has extremely high application prospects in the recovery and application of waste reagents in daily production, the purification of liquid products and multi-component separation. It can significantly shorten the distillation and purification time, save costs, have high product purity, and maintain the advantages of stable working conditions for a long time; while improving the separation efficiency, the purpose of high-purity separation is achieved.

[0115] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for adjusting the reflux ratio to improve distillation purity, characterized in that: The following steps are involved: Determine the full reflux position and the full extraction position of the liquid separation module; set the middle position between the full reflux position and the full extraction position as the initial position, and deflect the liquid separation module to the initial position; Collecting distillate and analyzing the purity of the distillate; determining the deflection direction and deflection position of the liquid separation module according to the comparison between the obtained purity and the set purity; and adjusting the liquid separation module to deflect toward the determined deflection direction and deflection position; repeating the operation multiple times until the measurement position at which the purity of the distillate reaches the maximum is screened out; According to the screened measurement positions, the liquid to be treated is distilled to improve the distillation purity of the liquid to be treated; The specific conditions for determining the deflection direction and deflection position of the liquid separation module are: When the purity of the distillate is less than the set purity, the liquid separation module is adjusted to deflect toward the direction of the total reflux position to a position between the measuring position and the total reflux position; or, When the purity of the distillate is greater than or equal to the set purity, the liquid separation module is adjusted to deflect toward the direction of the full extraction position to a position between the measuring position and the full extraction position; The liquid separation module is adjusted to deflect in a determined deflection direction, and a reflux ratio control system is used; the reflux ratio control system includes: A permanent magnet unit is arranged on the outer wall surface of the liquid separation module; An electromagnet module, disposed on one side of the permanent magnet unit and magnetically coupled to the permanent magnet unit; The power supply module comprises an adjustable DC regulated power supply and a power supply polarity conversion switch; the electromagnet module is sequentially connected to the power supply polarity conversion switch and the adjustable DC regulated power supply; By adjusting the output current of the adjustable DC regulated power supply, the magnitude of the magnetic attraction or repulsion of the electromagnet module on the permanent magnet unit is changed, so as to adjust the offset spacing or offset angle of the liquid separation module; The current direction of the electromagnet module is adjusted by the power polarity conversion switch to change the direction of the magnetic attraction of the electromagnet module to the permanent magnet unit, so as to adjust the deflection direction of the liquid separation module.

2. The method for improving distillation purity by adjusting the reflux ratio according to claim 1, characterized in that: The total reflux position is a configuration position of a liquid separation module for achieving total reflux of the distillate; The full extraction position is a configuration position of a liquid separation module for achieving full extraction of distillate.

3. The method for improving distillation purity by adjusting the reflux ratio according to claim 1, characterized in that: The set purity is the purity of the distillate reaching the qualified extraction standard.

4. The method for improving distillation purity by adjusting the reflux ratio according to claim 3, characterized in that: The set purity is 85% to 90%.

5. The method for improving distillation purity by adjusting the reflux ratio according to claim 1, characterized in that: The measuring position is a configuration position of a liquid separation module for collecting distillate, and is configured between the total reflux position and the total collection position.

6. The method for improving distillation purity by adjusting the reflux ratio according to claim 1, characterized in that: The reflux ratio control system further includes a processing module; the processing module is electrically connected to the adjustable DC regulated power supply and the power polarity conversion switch respectively; The processing module can determine the deflection direction and deflection displacement of the liquid separation module according to the comparison result of the obtained distillate purity and the set purity; then control the power polarity conversion switch to adjust the current direction of the electromagnet module according to the determined deflection direction of the liquid separation module; and control the output current size of the adjustable DC regulated power supply according to the determined deflection displacement of the liquid separation module.

7. A device for adjusting the reflux ratio to improve the distillation purity, characterized in that: The method for adjusting the reflux ratio to improve the distillation purity according to claim 1 is carried out by using the device, which comprises a distillation device, a liquid separation module and a reflux ratio control system, and the reflux ratio control system comprises: A permanent magnet unit is arranged on the outer wall surface of the liquid separation module; An electromagnet module, disposed on one side of the permanent magnet unit and magnetically coupled to the permanent magnet unit; The power supply module comprises an adjustable DC regulated power supply and a power supply polarity conversion switch; the electromagnet module is sequentially connected to the power supply polarity conversion switch and the adjustable DC regulated power supply; By adjusting the output current of the adjustable DC regulated power supply, the magnitude of the magnetic attraction or repulsion of the electromagnet module on the permanent magnet unit is changed, so as to adjust the offset spacing or offset angle of the liquid separation module; The current direction of the electromagnet module is adjusted by the power polarity conversion switch to change the direction of the magnetic attraction of the electromagnet module to the permanent magnet unit, so as to adjust the deflection direction of the liquid separation module.

8. The device for adjusting the reflux ratio to improve the distillation purity according to claim 7, characterized in that: The reflux ratio control system further includes a processing module; the processing module is electrically connected to the adjustable DC regulated power supply and the power polarity conversion switch respectively; The processing module can determine the deflection direction and deflection displacement of the liquid separation module according to the comparison result of the obtained distillate purity and the set purity; then control the power polarity conversion switch to adjust the current direction of the electromagnet module according to the determined deflection direction of the liquid separation module; and control the output current size of the adjustable DC regulated power supply according to the determined deflection displacement of the liquid separation module.

Images