WO2012048550A1 - Rectification column for preventing thermal-sensitisation and rectification separation process for preventing thermal-sensitisation of natural material - Google Patents

Abstract

Disclosed are a rectification column for preventing thermal-sensitisation and a rectification separation process for preventing thermal-sensitisation of natural material. The rectification column for preventing thermal-sensitisation comprises a rectification column (2), T-shaped condenser (4) arranged directly on the top of the rectification column (2) and connected with it without conduits, a baffle (12), a column bottom (3) and a falling-film reboiler (5), wherein the circular baffle (12) is disposed in the T-shaped condenser (4), an annular liquid-collecting slot (20) is disposed between the rectification column (2) and the T-shaped condenser (4) for collecting the liquid condensed in the T-shaped condenser (4) and introducing it into a liquid-collecting tank (6) disposed outside the column, the column bottom (3) is connected with the falling-film reboiler (5) by a centrifugal pump (7) to form a high-speed circulating system, the column bottom (3) has a shape of elongated tube, and the falling-film reboiler (5) is of stumpy shell-and-tube. The rectification column for preventing thermal-sensitisation is used in the rectification separation process for preventing thermal-sensitisation of natural material.

Description

 Anti-thermal distillation tower and natural material heat-resistant rectification separation process

 The invention relates to a natural substance anti-thermal precision separation process and equipment.

Background technique

 Say

 Spices of natural substances, etc., play an important role in the chemical, food, pharmaceutical and other industries. Natural flavors include animal flavors and vegetable flavors. Among them, animal flavors are more commonly known as musk, ambergris, etc.; there are many types of plant flavors, such as essential oils, scented resins, oleoresins, and the like. Artificial flavors include some alcohols and esters. In chemical, petrochemical, book

In the pharmaceutical, food and other industries, separation devices are essential. Conventional fine separations include batch separation (flow as shown in Figure 2) and continuous separation (flow as shown in Figure 3). The batch separation process consists mainly of batch-type fine columns, heating units, and condensing reflux units. The basic process is as follows: The material to be steamed is added to the tower kettle 29 for heating and evaporation at a time, and the generated gas passes through the fine tower 25 to enter the condenser 26 to be condensed into a liquid, and a part of the condensate is refluxed to the fine tower, and returned to the tower. The kettle is further heated to evaporate, and the other portion is taken out. After heating for a certain period of time, the light components in the tower material are completely distilled off, and the material of the tower kettle is discharged at one time, and the materials are no longer replenished. The continuous separation device has more feed device 40 and reboiler 35 than the intermittent separation device. The basic process of continuous separation is as follows: When driving, the raw materials to be steamed are added to the condensate tower to reach a certain liquid level, heating starts, the condensate obtained at the top of the tower is completely refluxed, and no feeding is required in the whole reflux stage; After the end of the stage, a part of the condensate flowing out of the condenser 34 is returned to the rest for production, and the liquid entering the tower is also partially recovered, and the remaining part enters the reboiler 35 to continue heating and evaporation, and the generated gas enters the fine stream. The column 33 flows from bottom to top, and at this time, it is continuously fed to ensure a constant liquid level of the material in the column. At present, most of the processes of fine separation are in the above two situations. Such a process requires long-term high-temperature heating of the materials. Most of the above-mentioned natural substances are sensitive to heat, and heat-sensitive reactions such as polymerization are often caused in the steam separation process due to excessive temperature and excessive heating time. Dehydration, oxidation, decomposition, etc., leading to coking, carbon deposits, discoloration, damage to the aroma, etc., which degrade the quality of the product and also cause waste of resources.

Summary of the invention

The object of the present invention is to solve the defect that the above-mentioned fine separation device is easy to cause heat sensitivity for the heat sensitive natural substance, and propose a new natural substance anti-thermal precision separation process and equipment. The technology is particularly suitable for separating a substance system which is prone to heat-sensitive reaction upon heating, and can prevent degradation of the product due to the heat-sensitive reaction, thereby ensuring Maintain the excellent quality inherent in the target product.

 The object of the present invention can be achieved by the following technical solutions:

 An anti-heat precision fine tower, as shown in Fig. 1, which is composed of a fine tower 2, a T-type condenser 4, a baffle 12, a tower kettle 3, a falling film reboiler 5, and a T-type condenser 4 It is placed directly on the top of the fine tower 2, without pipe connection in the middle, the distance is almost zero. The T-type condenser 4 is provided with a circular baffle 12, and the liquid condensed in the T-type condenser 4 cannot directly enter the fine tower. 2, to avoid the uncontrolled internal reflux, there is an annular sump 20 between the precision tower 2 and the T-type condenser 4, for collecting the liquid condensed in the T-type condenser 4, and introducing the liquid collection tank outside the tower In the sixth, the fine tower 2 is a plate tower or a packed tower, preferably a packed tower; the tower tank 3 and the falling film reboiler 5 are connected by a centrifugal pump 7 into a high-speed circulation system, and the tower tank 3 is elongated and tubular. The falling film type reboiler 5 is a chunky tube type.

 The above-mentioned anti-heating precision crucible tower, the T-type condenser 4, and the fine crucible tower 2 are connected by a flange, and the refrigerant of the T-type condenser 4 enters through the duct 18 and then flows out from the duct 19.

 In the above-mentioned anti-heating precision crucible tower, the liquid collection tank 20 is disposed at the top outlet of the fine crucible tower 2, and the edge of the liquid collection tank 20 is higher than the connection port of the fine crucible tower 2 and the T-type condenser 4. There is a gap between the baffle 12 and the baffle 12, and the liquid condensed in the T-type condenser 4 can flow into the sump 4.

 The above-mentioned anti-heating precision crucible tower, the baffle 12 is welded above the interface of the fine crucible tower 2 and the T-type condensation tower 4, and has a gap with the top of the fine crucible tower 2, so that the upward steam can pass, and at the same time The diameter of the baffle 12 is larger than the inner edge of the sump 20, so that the condensed liquid in the T-type condenser 4 flows into the sump 20 without directly entering the concentrating tower 2.

 In the above-mentioned anti-heat-precision precision tower, the tower tank 3 is an elongated tubular shape, and the volume is 1/10 1/50 of the conventional tower kettle, so that the residence time of the material is correspondingly greatly shortened, and the long time is not long. The ground stays in a high temperature environment.

 The above-mentioned anti-heating precision crucible tower, the falling film type tube re-boiler 5, has a short body (high aspect ratio less than 1) cylinder, and the fluid is in the column under the action of the liquid circulation pump at the bottom of the tower The average dwell time from top to bottom in each tube is very short, usually around 0.1-3 seconds. Therefore, although the temperature is the highest in the whole process, the contact time between the material and the heating wall is extremely short, so that the heat-sensitive reaction can be effectively avoided. In contrast, the conventional reboiler reboiler is the opposite. When the material is cooked at a high temperature for a long time, the heat-sensitive reaction is generally difficult to avoid.

The above-mentioned anti-heating precision crucible tower is composed of a pipe 23, a liquid collection tank 6, a pipe 16, a centrifugal pump 8, and a pipe 15, and the liquid collection tank 6 is for collecting the liquid flowing out of the liquid collection tank 20. The liquid in the liquid collection tank 6 is returned to the fine tower 2 by the centrifugal pump 8 to be refluxed, and a part is taken out as a product. A natural substance anti-heating fine separation process, as shown in Figure 1, the whole process is continuous, it adopts the above The anti-thermal precision tower, the specific steps are as follows:

 Step 1. Reduce the pressure in the entire fine column to the required operating pressure by the vacuum system 22 (usually control the operating pressure below the temperature sensitive point of the fine material). When driving, pass the mixture through the pipe 1 The tower 2 enters the tower tank 3. When a certain liquid level is reached, the pump 7 is turned on, and the material in the tower tank 3 is driven into the falling film type reboiler 5 through the pipes 13 and 14 to be heated, and the gas-liquid mixture is produced. Under the action of the pressure difference, it enters the fine tower 2 through the pipeline 11 to perform fine boring;

 Step 2. The gas enters the T-type condenser 4 and condenses into a liquid. Due to the baffle 12, the liquid can only flow from the peripheral side of the baffle into the sump 20, and then enters the sump 6 through the pipe 23, and then passes through the pipe. 16 and the centrifugal pump 8 pumps the liquid in the header tank 6 into the condensing tower 2 for total reflux, the T-type condenser 4 is placed directly above the condensing tower 2, and the gas enters from the middle of the tank of the condenser 4, Since the distance between the top of the fine column 2 and the condenser 4 is almost zero, the gas in the fine column 2 can be rapidly condensed into a liquid and cooled below the temperature sensitive temperature, due to the presence of the baffle 12, The condensed liquid can only flow from the circumferential side of the baffle 12 into the sump 20;

 Step 3. When the whole reflux is established for a period of time, the whole tower is balanced, the part is finally taken out, the valves 9 and 10 are opened, the light component of the tower top is taken out through the valve 10, and the high-boiling heavy component in the tower tank 3 passes through the valve. 9 is produced, and at the same time, the feed is started through the pipe 1, so that the liquid level in the tower 3 is maintained at a normal level, thereby entering the continuous fine operation stage.

Advantages of the invention:

 1. Compared with traditional precision equipment (Figure 2, Figure 3), the anti-heat precision tower (shown in Figure 1) uses a T-type condenser, which greatly shortens the distance between the fine tower and the condenser. , thereby minimizing the residence time of the vapor phase between the top of the fine crucible and the condenser, so that the vapor rising from the fine tower to the top of the tower can be quickly condensed into a liquid and cooled below the temperature sensitive temperature. , can effectively prevent the occurrence of thermal reaction between the top of the tower and the condenser.

 2. Anti-thermal precision tower (shown in Figure 1) A circular baffle and an annular sump are designed between the T-condenser and the fine turret, so that the condensed liquid from the T-type condenser is only It can flow into the sump, thus preventing the condensate from directly entering the condensing tower, which facilitates precise control of the recirculation.

 3. Compared with the traditional precision equipment (Figure 2, Figure 3), the anti-heat precision tower (shown in Figure 1) uses a slender tubular tower, which is greatly reduced in size, only the traditional tower 1/50 1/10, and due to the action of the bottom circulation pump, the average residence time of the materials in the tower is only 1/50 1/10 of the traditional tower. Thus, the tower material is prevented from being cooked for a long time in the high temperature region of the tower, thereby greatly suppressing the occurrence of the heat-sensitive reaction in the tower.

4. Anti-thermal precision tower (shown in Figure 1) A falling film tube reboiler with a short and thick structure, with traditional fine design Compared with the conventional tube-type reboiler 35 in the preparation, the liquid from the top of the falling film tube reboiler will continuously update the vaporized surface, so that the surface heat transfer effect is good, the vaporization speed is fast, and the liquid and high temperature columns are simultaneously The contact time of the inner surface of the tube is extremely short, which can effectively prevent the liquid material from being heated by overheating and high temperature for a long time, thereby effectively avoiding the occurrence of heat-sensitive reaction in the heat exchanger. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a heat-sensitive fine separation process and equipment of the present invention, wherein 1 is a feed port, 2 is a fine sputum tower, 3 is a tower kettle, 4 is a T-type condenser, and 5 is a falling film type. Boiling device, 6 is a liquid collection tank, 7 and 8 are centrifugal pumps, 9, 10, 21, 24 are valves, 11, 13, 14 are tower material conveying pipes, 12 are baffles, 15, 16, 23 are towers The top condensate conveying pipe, 17 is the top condensate recovery port, 18, 19 is the condensing medium conveying pipe, 20 is the sump, and 22 is the vacuum system. 2 is a conventional batch fine boring equipment, wherein 25 is a fine boring tower, 26 is a condenser, 27 is a vacuum system, 28, 30, 31 are valves, and 29 is a tower kettle. Figure 3 is a conventional continuous fine boring equipment, wherein 32 is a tower kettle, 33 is a fine turret, 34 is a condenser, 35 is a reboiler, 36 is a vacuum system, 37, 38, 39 are valves, 40 is a feed port . Figure 4 shows the process and equipment for the separation of the two towers of the anti-thermal (the equipment diagram of the embodiments 2 and 3), 2 is the fine tower A, and T2 is the fine tower 8. detailed description

 Example 1

The mixed solution of the crude oil of eucalyptus leaves and ethanol is passed from the pipeline 1 through the condensing tower 2 into the tower kettle 3, the diameter of the sorghum tower 2 is 0.15 m, the number of theoretical trays is 40, and the total volume of the tower kettle 3 is 50 liters. The aspect ratio is 3:1. The vacuum system 22 is turned on, the pressure of the entire fine boring system is lowered to 400 mmHg, and the falling film reboiler 5 starts heating. The volume of the falling film reboiler 5 is 500 L, and the heating of the falling film reboiler 5 is started. The medium temperature was 140 °C. At the same time, the pump 7 is turned on to circulate the liquid material in the tower tank 3. The circulation flow rate of the centrifugal pump is 40 m ³ /h, and the vapor phase generated in the falling film type reboiler 5 enters the fine tower together with the unvaporized liquid. At the bottom of the bottom, the vapor phase is separated by the fine column 2, and the vapor phase reaching the top is rapidly condensed in the T-type condenser 4 into a liquid flowing into the liquid collecting tank 20, and then enters the liquid collecting tank 6 through the line. The centrifugal pump 8 is used to directly drive the condensate in the liquid collection tank into the fine column 2 for full reflux operation. When full reflux is carried out for a period of time After the balance is established, the part is finally taken out, and the valves 9 and 10 are opened, and the reflux ratio is 2/5. At the same time, the mixed solution of the crude oil and the ethanol of the eucalyptus leaves is started through the pipe 1, and the liquid level in the tower 3 is kept constant, and the To the continuous precision stage. The purity of 1,8-cineole in the collected liquid of the tower was 99.7%, and the amount of production was 300kg/h. Compared with the conventional continuous steaming, the residence time of the material in the tower was greatly shortened, which was only conventional continuous. The 1/40 1/30 of the steamed steam is 1/200 1/100 of the conventional intermittent steaming, and the heat-sensitive reaction can be almost completely avoided. Because of this, the recovery rate of 1,8-cineole qualified products can be as high as 98.5% or more, which is more than 3% higher than conventional continuous steaming, and the product smells pure, clear and transparent.

 Example 2

The two-column process was used to separate the masson pine turpentine. The specific device structure and operation method are similar to those of Embodiment 1 (as shown in FIG. 4). Add the masson pine turpentine to the fine boring tower A2. The precision tower A2 has a diameter of 0.15 m, the theoretical number of plates is 40, the total volume of the tower kettle 3 is 50 L, and the height to diameter ratio of the tower kettle is 3:1. The pressure control of the fine column A2 is 40 mmHg, and the heating temperature of the falling film reboiler 5 is 140 °C. The circulating flow rate of the centrifugal pump is 30 m ³ /h. After the whole reflux temperature is stable for a period of time, the top temperature of the fine tower A1 is controlled at about 90 °C, and α-pinene is produced at the top. The recovery amount is 180 kg/h, and its purity can reach 98% or more. The yield of terpenes can reach over 99.5%, which is more than 8 percentage points higher than conventional continuous steaming. The material at the bottom of the crucible 2 crucible is separated into the fine crucible 2 by the bottom pump 7. The pressure of the fine crucible 2 is controlled to 40 mmHg, and the temperature of the falling film reboiler is 150 °C. The circulating flow rate of the centrifugal pump is 30 m ³ /h. The top part is produced with β-pinene, the amount of production is 80kg/h, and the heavy component of turpentine is produced at the bottom, commonly known as heavy oil. The purity of β-pinene can reach above 98.5, and the yield can reach over 99.0%, which is more than 7 percentage points higher than conventional continuous steaming.

 Compared with the conventional continuous steaming, the residence time of the materials in the two towers is greatly shortened, which is only 1/60 1/50 of the continuous steaming of the conventional two towers, which is 1/500 1/400 of the conventional intermittent steaming. , The heat-sensitive reaction of the turpentine component can be almost completely avoided.

 Example 3

Similar to the operation of Example 2, a mixed solution of dihydromyrcenol, dihydromyrcene, and isopropyl alcohol was added to the fine boring system, and the operating pressure of the fine enthalpy 2 was controlled by a vacuum system of 20 mmHg. The diameter of the diaphragm is 0.15m, the number of theoretical plates is 40), the heating temperature of the falling film reboiler 5 is 140 °C, the circulating flow rate of the centrifugal pump 7 is 40m ³ /h, and the total reflux temperature is maintained for a period of time after the temperature of the whole tower is stabilized. Dihydromyrcenol was produced at the bottom of the fine tower A2 (recovery amount 300 kg/h, reflux ratio 2/5), and its purity was 95.6%. Then, it is sent to the fine turret BT2 for fine boring, and more than 99.5% of the dihydromyrcenol product can be obtained from the top of the condensing tower BT2. Through this anti-heat-sensitive device and process operation, the average residence time of the materials in the two towers is only about 1/50 of the continuous distillation of the conventional two towers, which is a routine interval. About 1/400 of steamed rice. Therefore, the yield of dihydromyrcenol can be as high as 92% or more, which is about 14% higher than that of conventional continuous steaming, and more than 20% higher than conventional intermittent steaming. The resulting product has a pure odor and does not have any scorching odor.

Claims

Claim 1. A heat-sensitive precision boring tower, which is characterized in that: it consists of a fine turret (2), a T-type condenser (4), a baffle (12), a tower kettle (3), a falling film reboiler (5) It consists of a recirculating system. The T-type condenser (4) is placed directly on the top of the fine tower (2). The middle is not connected by pipes. The distance is almost zero. The T-type condenser (4) has a circular block. The liquid condensed in the plate (12), T-type condenser (4) cannot directly enter the fine column (2), the fine column (2) and the T-type condenser (4) There is an annular sump (20) for collecting the condensed liquid in the T-type condenser (4), and introducing it into the liquid collecting tank (6) outside the tower, the tower tank (3) and the falling film The reboiler (5) is connected to a high-speed circulation system by a centrifugal pump (7), the tower tank (3) is elongated and tubular; and the falling film reboiler (5) is a chunky tube type.  2. The anti-heating precision crucible tower according to claim 1, wherein: the fine crucible tower (2) is a plate tower or a packed tower.  3. The anti-heating precision crucible tower according to claim 2, characterized in that: the fine crucible tower (2) is a packed tower. 4. The anti-heating precision crucible tower according to claim 1, wherein: the T-type condenser (4) and the fine crucible tower (2) are connected by a flange, and the T-type condenser (4) The refrigerant enters the pipe (18) and flows out of the pipe (19).  5. The anti-heating precision crucible tower according to claim 1, wherein: the sump (20) is disposed at a top outlet of the fine boring tower (2), and the sump (20) The edge is higher than the connection between the fine tower (2) and the T-type condenser (4), and there is a gap between the baffle (12), and the liquid condensed in the T-type condenser (4) can only flow into In the sump (4).  6. The anti-heating precision crucible tower according to claim 1, wherein: the baffle (12) is welded above the interface between the fine crucible tower (2) and the T-type condensation tower (4), There is a gap between the top of the fine tower (2) to allow the upward steam to pass, while the diameter of the baffle (12) is larger than the inner edge of the sump (20), and the liquid condensed in the T-type condenser (4) It can flow into the sump (20) without going directly into the concentrating tower (2).  7. The heat-sensitive precision turret according to claim 1, wherein: said tower kettle (3) is in the form of an elongated tube having a volume of 1/10 1/50 of a conventional tower.  8. The anti-heating precision crucible tower according to claim 1, wherein: said falling film type tube reboiler (5) has a appearance of a short, obese cylinder, and functions as a liquid circulation pump at the bottom of the column. Underneath, the average residence time of the fluid in the column from top to bottom is very short, usually about 0.1-3 seconds.  9. The anti-heating precision crucible tower according to claim 1, wherein: said reflow system is provided by a pipe (23), 1 The liquid collection tank (6), the pipeline (16), the centrifugal pump (8) and the pipeline (15) are used, and the liquid collection tank (6) is used for collecting the liquid flowing out of the sump (20), and the liquid collection tank (6) In the liquid, a part of the liquid is sent back to the fine column (2) by a centrifugal pump (8) for reflux, and a part is taken as a product. 10. A natural substance heat-sensitive fine separation process using the heat-sensitive precision boring tower according to claim 1, wherein the entire process is continuous, and the heat-sensitive precision turret according to claim 1 is used. The specific steps are as follows: Step 1. Reduce the pressure in the entire fine tower to the required operating pressure by the vacuum system 22, and drive the mixture from the pipeline (1) through the fine tower (2) to the tower when driving ( 3), when the certain level is reached, turn on the pump (7), the material in the tower kettle (3) is driven into the falling film reboiler (5) through pipes (13 and 14) for heating, and the resulting gas-liquid mixture passes through the pipe under the pressure difference (11) Enter the fine column (2) for fine boring; Step 2. The gas enters the T-type condenser (4) and condenses into a liquid. Due to the baffle (12), the liquid can only be removed from the side of the baffle (12). Flow into the sump (20), then enter the sump (6) through the pipe (23), and then pump the liquid in the sump (6) into the sump through the pipe (16) and the centrifugal pump (8). In column (2), full reflux is performed, the T-type condenser (4) is placed directly above the fine column (2), and gas enters from the middle of the tank of the condenser (4), due to the top of the fine tower (2) The distance between the condensers (4) is almost zero, so the gas in the fine column (2) can be quickly condensed into a liquid and cooled below the temperature sensitive temperature, condensed due to the presence of the baffle (12) The liquid can only flow from the peripheral side of the baffle (12) into the sump (20);  Step 3. When the whole reflux is established for a period of time, the whole tower is equilibrated, and part of the production is started. The valve (9) and the valve (10) are opened, and the light component of the top of the tower is taken out through the valve (10). 3) The high-boiling heavy component is produced through the valve (9), and the feed is started through the pipe (1), so that the liquid level in the tower (3) is maintained at a normal level, thereby entering the continuous fine operation stage. . 2