CN107837554B - Quality control method of dividing wall tower - Google Patents
Quality control method of dividing wall tower Download PDFInfo
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
- B01D3/14—Fractional distillation or use of a fractionation or rectification column
- B01D3/141—Fractional distillation or use of a fractionation or rectification column where at least one distillation column contains at least one dividing wall
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- B—PERFORMING OPERATIONS; TRANSPORTING
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- B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
- B01D3/42—Regulation; Control
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- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
- B01D3/42—Regulation; Control
- B01D3/4211—Regulation; Control of columns
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- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
- C07C29/76—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment
- C07C29/80—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment by distillation
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- C—CHEMISTRY; METALLURGY
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Abstract
The invention relates to a quality control method of a dividing wall tower, which mainly solves the technical problems that the operation control of the existing dividing wall tower is difficult, the stability is not good, and the product quality and the yield are not easy to control. The invention adopts five control areas of the dividing wall tower: the technical scheme of controlling the temperature, flow and liquid level in the raw material feeding control area, the tower top reflux and extraction control area, the liquid collection and distribution control area, the side extraction control area and the tower kettle extraction control area better solves the technical problems and can be used in the industrial production of the dividing wall tower.
Description
Technical Field
The invention relates to a quality control method of a dividing wall tower, which can be used in the industrial production of the dividing wall tower.
Background
Rectification is the most mature and widely applied separation technology in petrochemical production, but the energy consumption in the rectification process is huge, and it is estimated that 40-70% of the energy consumption in the chemical process is used for separation, and the rectification energy consumption accounts for 95% of the energy consumption. In order to reduce the energy consumption in the rectification process, researchers at home and abroad carry out extensive research, and the dividing wall tower is widely concerned as a typical rectification energy-saving device or a process strengthening energy-saving technology.
The dividing wall tower is characterized in that one or more vertical partition plates with certain length or partition plates with inclined angles are arranged in one rectifying tower, and a set of vaporization and condensation system is adopted to simultaneously separate three or more products. Because only one set of vaporization and condensation system is provided and the remixing of the intermediate components is avoided when multi-tower rectification is adopted, the investment is saved by 20-30% and the energy consumption is reduced by 20-40% in the dividing wall rectification technology compared with the traditional rectification technology.
Actually, in 1930, Eeic w. luster (US1915681) provided a concept of a dividing wall column for the separation of cracked gas, but the first dividing wall column (BASF) was not put into industrial production until 1985, and only 200 or more dividing wall columns were used in industrial application so far, which was difficult to be widely popularized, and the fundamental reason is that the dividing wall column has a great difficulty in operation and control, besides the lack of reliable structural design.
Taking the most common dividing wall column for three-component separation as an example, the dividing wall is arranged along the axial direction of the column, and is divided into a common rectification section above the dividing wall, a common stripping section below the dividing wall and a dividing wall section where the dividing wall is arranged, wherein the dividing wall section is divided into a feeding side and a product side according to different feeding and intermediate component extraction. Therefore, compared with the conventional rectifying tower, the dividing wall tower has more freedom due to the structural particularity, besides the same process parameters as the conventional rectifying tower, such as operating pressure, cold and heat load, reflux ratio, product extraction amount and the like, the dividing wall tower also comprises the extraction of a side line product and the distribution of gas phase and liquid phase at two sides of a partition plate, and the process parameters are highly coupled, and the change of any one of the process parameters can bring direct influence on the operation of other parameters, for example, the change of the reflux liquid amount at the top of the tower not only influences the quality of the product at the top of the tower, but also directly changes the total amount of the distillate liquid at the bottom of a common rectifying section, and under the condition of fixing the distribution ratio of the liquid phase at two sides, the distribution liquid amount at two sides directly influences the distribution liquid amount at two sides, and also directly influences the pre-separation effect at the feeding side of the dividing wall section and the; if the amount of the liquid distributed on the two sides is fixed, the change of the amount of the reflux liquid on the top of the tower directly destroys the material balance in the tower and influences the processes of mass transfer, heat transfer and gas-liquid balance, so that the product quality and stable operation control of the dividing wall tower are obviously influenced by the high coupling and chain reaction among the process parameters in the dividing wall tower, which is the direct reason that the dividing wall tower is difficult to realize stable control, and is a research focus and difficulty in the development process of the dividing wall tower.
At present, the Operation and quality control of the dividing wall column are disclosed in less patent publications, and CN102631791A discloses a control method of the dividing wall column, which is mainly to add a control loop on the basis of three-point control method (Operation of integrated route-product (petlyuk) distillation columns, e.a.wolff, s.skogestad, ind.eng.chem.res.,1995,34(6): 2094-2103) of e.a.wolff et al, i.e. to add a control loop to control the purity of the overhead product by adjusting the overhead reflux amount, to control the purity of the side product by adjusting the side draw amount, and to control the purity of the bottom product by adjusting the bottom steam amount of the tower, to control the content of heavy components in the ascending gas phase at the top of the feeding side by adjusting the liquid phase distribution ratio at both sides of the dividing wall column dividing wall. Although the product quality is correspondingly controlled, the discharge amount of products at the top of the tower and the bottom of the tower are not controlled, the yield of each product including a side product cannot be ensured, and meanwhile, the liquid levels of a plurality of areas in the tower, such as a reflux area at the top of the tower, a liquid collecting and distributing area at the bottom of a common rectifying section and a tower bottom area are not controlled, so that the material balance and stable control of the dividing wall tower are difficult to ensure.
Obviously, the control method in the prior art cannot ensure the product quality and the product yield, and cannot realize stable operation, so that a more effective quality control method needs to be developed to comprehensively control a plurality of process parameters or operation variables of the dividing wall tower, realize the stable operation of the dividing wall tower, and simultaneously ensure the quality and the yield of each product.
Disclosure of Invention
The invention aims to solve the technical problems that the operation control of the dividing wall tower is difficult, the stability is poor and the product quality and yield are difficult to control in the prior art. The invention provides a quality control method of a dividing wall tower, which realizes the comprehensive control of the dividing wall tower by controlling the temperature, the flow and the liquid level of different areas in the dividing wall tower, ensures the product quality and the product yield, realizes the stable control and can be used in the industrial production of the dividing wall tower.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows: the dividing wall tower comprises 5 control areas which are respectively: the system comprises a raw material feeding control area, a tower top reflux and extraction control area, a liquid collecting and distributing control area, a side extraction control area and a tower kettle extraction control area, wherein the control method of each control area comprises the following steps:
(1) raw material feeding control area: controlling the raw material feeding amount by adopting a flow controller;
(2) the tower top reflux and extraction control area: controlling the cold energy of a condenser at the top of the tower by adopting a temperature controller, controlling the extraction amount of products at the top of the tower by adopting a flow controller, and controlling the amount of reflux liquid at the top of the tower by adopting a liquid level controller;
(3) liquid collection and distribution control area: controlling the flow of the distillate at the bottom of the public rectification section by adopting a liquid level controller, and controlling the distribution liquid amount at the feed side of the partition section by adopting a temperature controller;
(4) side draw control zone: controlling the side product extraction amount by adopting a flow controller;
(5) the extraction control area of the tower kettle: the heat of a reboiler of the tower kettle is controlled by a temperature controller, and the product extraction amount of the tower kettle is controlled by a liquid level controller.
In the technical scheme, the flow controller in the raw material feeding control area controls the raw material feeding amount, and the actual raw material feeding amount is automatically adjusted according to the set raw material feeding amount.
In the technical scheme, the temperature controller in the tower top reflux and extraction control area controls the temperature of the sensitive plate of the public rectifying section of the dividing wall tower, and the cold quantity of the tower top condenser is automatically adjusted according to the temperature of the sensitive plate. Due to the corresponding relation between the temperature and the composition, the temperature control of the public rectification section sensitive plate is realized by adjusting the cold energy of the condenser at the top of the tower, and the product quality at the top of the tower can be ensured. Typically, the common rectification section sensitive plate is located at the top or middle upper part of the common rectification section.
In the technical scheme, the flow controller in the tower top reflux and extraction control area controls the extraction amount of the tower top product, the flow is set according to the feeding amount of the raw material and the percentage content of the corresponding light component in the feeding composition, and the actual extraction amount of the tower top product is automatically adjusted according to the set product extraction amount, so that the yield of the tower top product is ensured.
In the technical scheme, the liquid level controller in the tower top reflux and extraction control area controls the liquid level of the tower top reflux tank, and the flow of the tower top reflux liquid is automatically adjusted according to the liquid level. Because the reflux and the extraction at the top of the tower are correspondingly controlled, the liquid level of the reflux tank at the top of the tower is stable, the stable operation of the reflux and the extraction areas at the top of the tower is equal to that of the reflux and the extraction areas at the top of the tower, and the material balance of light components in the dividing wall tower is ensured.
In the technical scheme, the liquid level controller in the liquid collection and distribution control area controls the liquid level of the liquid collection area at the bottom of the public rectifying section of the dividing wall tower, and the total flow of the bottom distillate liquid is automatically adjusted according to the liquid level. Since the liquid distribution on both sides of the partition plate directly affects the separation result of the dividing wall column, and the distributed liquid comes from the liquid in the liquid collecting area at the bottom of the common rectification section, the liquid level control is carried out on the area, which is beneficial to avoiding the material leakage of the gas phase or the overflow of the liquid phase, and simultaneously, the liquid distribution effect on the side of the partition plate and the stable operation of the dividing wall column are ensured.
In the technical scheme, the temperature controller in the liquid collection and distribution control area controls the temperature of the sensitive plate on the feeding side of the dividing wall section of the dividing wall tower, and the distribution liquid amount on the feeding side is automatically adjusted according to the temperature of the sensitive plate. The main function of the feed side is to realize the pre-separation of the raw materials, namely, part of middle components enter the public rectification section along with light components, and the rest of middle components enter the public stripping section along with heavy components, so that the temperature control of the sensitive plate at the feed side of the bulkhead section is realized by adjusting the liquid distribution amount at the feed side, the pre-separation effect can be ensured, and the heavy components are effectively prevented from entering the public rectification section from the upper part of the partition plate and then entering the product side in a liquid phase mode to influence the quality of a side line product. Usually the sensitive plate on the feed side of the dividing wall section of the dividing wall column is located at the top or in the middle upper part of the feed side.
In the technical scheme, the flow controller in the side draw control area controls the side draw amount of the side product, the flow rate of the side product is set according to the feeding amount of the raw material and the percentage content of the corresponding intermediate component in the feeding composition, and the actual side draw amount of the side product is automatically adjusted according to the set product draw amount, so that the yield of the side product is ensured.
In the technical scheme, the temperature controller in the extraction control area of the tower kettle controls the temperature of the sensitive plate of the public stripping section of the dividing wall tower, and the heat of the reboiler of the tower kettle is automatically adjusted according to the temperature of the sensitive plate. By controlling the reasonable temperature range of the sensitive plate, the heavy components can be prevented from rising too much to influence the side line product quality, and the full evaporation of the intermediate components can be ensured, so that the product quality of the tower kettle is ensured. Usually, the sensitive plates of the common stripping section of the dividing wall column are positioned at the top or in the middle upper part of the common stripping section.
In the technical scheme, the liquid level controller in the tower kettle extraction control area controls the liquid level of the tower kettle of the dividing wall tower, and the product extraction amount of the tower kettle is automatically adjusted according to the liquid level. Obviously, the liquid level of the tower kettle is controlled, so that the ascending vapor amount in the tower is favorably ensured, and the stable operation of the dividing wall tower is realized; meanwhile, on the basis of effectively controlling the extraction amount of products at the top and at the side line of the tower, the yield of products at the bottom of the tower is ensured, and the material balance of the whole tower is realized.
In summary, based on the corresponding relationship between the temperature and the composition in the rectifying tower, the temperature of the sensitive plates in the common rectifying section directly affects the quality of the product at the top of the tower, and the temperatures of the sensitive plates on the feed side of the dividing wall section and the common stripping section directly affect the contents of the heavy components falling from the top of the product side and the heavy components rising from the bottom of the common stripping section, i.e. directly affect the quality of the side product, so the quality of the products at the top of the tower and the side product can be ensured by controlling the appropriate temperature of the sensitive plates. According to the invention, the temperature of the public rectifying section sensitive plate is controlled by adjusting the cold quantity of the tower top condenser, so that the quality of a tower top product is ensured; the temperature control of sensitive plates on the feed side of a partition wall section and a public stripping section is respectively realized by adjusting the liquid distribution amount of the feed side and the heat of a reboiler of a tower kettle in a liquid collection and distribution control area, so that the control of impurities on the product side, particularly the content of heavy components is realized, and the quality of a side product is ensured; meanwhile, on the premise of ensuring the product quality, the invention respectively realizes the control of the raw material feeding amount, the tower top and side line product extraction amount through three flow controllers in the raw material feeding control area, the tower top reflux and extraction control area and the side line extraction control area, thereby ensuring the yield of the tower top and side line products; in addition, based on the stable operation of the dividing wall tower and the influence of the steam amount or the gas-liquid flow in the tower on the product extraction amount, the invention respectively realizes the control of the liquid level of the tower kettle and the liquid level of the condensing tank at the top of the tower by adjusting the tower kettle extraction amount in the tower kettle extraction control area and the reflux liquid flow in the tower top reflux and extraction control area, and realizes the liquid level control of the area by adjusting the total amount of bottom distillate liquid in the liquid collection and distribution control area, thereby ensuring the gas-liquid flow in the tower and the material balance of the whole tower on the one hand, and further ensuring the product quality and yield of the tower kettle under the condition that the effective control is realized on the product quality and yield of the tower top and side lines on the other hand, ensuring the stable operation of each area of the whole tower and realizing the stable operation of the whole dividing wall tower; therefore, the temperature, the flow and the liquid level of the five control areas, namely the raw material feeding control area, the tower top reflux and extraction control area, the liquid collection and distribution control area, the side extraction control area and the tower kettle extraction control area are respectively controlled, so that the quality and the yield of products at the tower top, the side line and the tower kettle can be ensured, the stable operation of each area including the tower top, the tower kettle, the bottom of a public rectification section and the like in the dividing wall tower can be ensured, and the stable operation of the whole tower is finally realized. Therefore, the technology disclosed by the invention can better solve the technical problems that the operation control of the conventional dividing wall tower is difficult, the stability is poor and the product quality and yield are difficult to control.
Drawings
FIG. 1 is a schematic view of a method for controlling the quality of a dividing wall column according to the present invention;
FIG. 2 is a schematic diagram of a dividing wall column control process described in comparative example 1;
FIG. 3 is a schematic diagram of a dividing wall column control process described in comparative example 2.
In FIG. 1, C101 is a dividing wall column, E101 is a top condenser, and E102 is a bottom reboiler; TIC is a temperature controller, FIC is a flow controller, and LIC is a liquid level controller; the partition plate is arranged along the middle part of the tower to divide the dividing wall tower into 4 parts, wherein I is a public rectifying section, II is a public stripping section, III is a dividing wall section feeding side, and IV is a dividing wall section product side; n1 is a common rectifying section sensitive plate, N2 is a bulkhead section feeding side sensitive plate, and N3 is a common stripping section sensitive plate; the material flow (101) is raw material, the material flow (102) is top product, the material flow (103) is side product, the material flow (104) is bottom product, the material flow (105) is top reflux liquid, the material flow (106) is bottom distillate of the public rectification section, the material flow (107) is distribution liquid at the feeding side of the dividing wall section, and the material flow (108) is distribution liquid at the product side of the dividing wall section.
In fig. 1, a raw material feeding area adopts a flow controller to control the opening of a raw material feeding valve; the tower top reflux and the temperature of a public rectification section sensitive plate N1 are adopted in the region to control the cooling power or the refrigerant flow of a tower top condenser E101, the liquid level of a tower top reflux tank is adopted to control the flow of the tower top reflux liquid, and a flow controller is adopted to control the opening degree of a tower top product extraction regulating valve; the liquid collecting and distributing area adopts the liquid level of the liquid collecting area at the bottom of the public rectifying section to control the total flow of the bottom distillate liquid and adopts the temperature of a sensitive plate N2 at the feeding side to control the opening of a regulating valve for distributing the liquid at the feeding side; the opening degree of a lateral line product extraction regulating valve is controlled by a flow controller in the lateral line extraction area; in the tower bottom extraction area, the temperature of a public stripping section sensitive plate N3 is adopted to control the heating power or the heating medium flow of a tower bottom reboiler E102, and the liquid level of the tower bottom is adopted to control the opening degree of a tower bottom product extraction regulating valve.
In FIG. 2, the apparatus and the streams of the dividing wall column, except for the feed preheater, are in accordance with FIG. 1, and the control scheme is: the liquid amount of the reflux at the top of the tower is controlled by the composition of the product at the top of the tower, the output amount of the side product is controlled by the composition of the side product, the heat load of a reboiler at the bottom of the tower is controlled by the composition of the product at the bottom of the tower, and the proportion of the liquid distributed at the two sides of the partition plate is controlled by the content of the heavy component in the gas phase at the top of the.
In FIG. 3, the apparatus and the streams of the dividing wall column correspond to those of FIG. 1, and the control scheme is as follows: the method comprises the steps of controlling the amount of tower top reflux liquid through the temperature of a sensitive plate at the top of the product side of a partition section, controlling the amount of tower top product extracted through the liquid level of a tower top condenser, controlling the amount of distribution liquid at the feed side of the partition section through the liquid level of a liquid collection region at the bottom of a public rectification section, controlling the proportion between the amounts of distribution liquid at two sides of a partition plate through a proportion controller, controlling the amount of side line product extracted through the temperature of the sensitive plate at the bottom of the product side of the partition section, and controlling the.
The invention is further illustrated by the following examples.
Detailed Description
[ example 1 ]
The benzene/toluene/mixed xylene material is used as a raw material, and the composition of the benzene/toluene/mixed xylene material is 12.80 percent of benzene, 70.69 percent of toluene and 16.51 percent of mixed xylene by weight percentage. Taking the feeding flow rate of 80g/min as a reference, separating according to the operation control method of the dividing wall tower shown in figure 1, obtaining a benzene product at the tower top, obtaining a toluene product at the side line, and obtaining a mixed xylene product at the tower bottom. The total number of theoretical plates of the dividing wall tower is 70, the number of theoretical plates of the public rectification section is 15, the number of theoretical plates of the feed side and the product side of the dividing wall section is 35, raw materials enter from the 23 rd theoretical plate of the feed side I of the dividing wall section from top to bottom, methylbenzene is extracted from the 17 th theoretical plate of the product side III of the dividing wall section from top to bottom, the operation pressure is normal pressure, the control temperatures of sensitive plates N1, N2 and N3 are 79.8 ℃, 108.4 ℃ and 113.5 ℃, the extraction amounts of the tower top and the side line are respectively controlled to be 10.2g/min and 56.5g/min, the liquid levels of a condensing tank, a liquid collecting region and a tower kettle at the tower top are respectively controlled to be 50%, 65% and 75%, and the control results are shown in Table 1. It can be seen that the purity of the benzene, toluene and mixed xylene products reaches more than 99.9%, the yield of the benzene and toluene also reaches more than 99.9%, meanwhile, the stabilization time of the whole tower is shorter, about 3-4 hr, and the separation effect and the stabilization time are obviously superior to those of the comparative example, which shows that the quality control method related by the invention realizes the ideal control effect of the dividing wall tower.
[ example 2 ]
The benzene/toluene/mixed xylene material is used as a raw material, and the composition of the benzene/toluene/mixed xylene material is 33.85 percent of benzene, 54.61 percent of toluene and 11.54 percent of mixed xylene by weight percentage. Taking a feeding flow rate of 80g/min as a reference, separating according to an operation control method of the dividing wall tower shown in figure 1, wherein the total theoretical plate number of the dividing wall tower is 70, the theoretical plate number of a common rectification section is 20, the theoretical plate numbers of a feeding side and a product side of the dividing wall tower are both 30, raw materials enter from a 17 th theoretical plate of a feeding side I of the dividing wall section from top to bottom, methylbenzene is extracted from a 15 th theoretical plate of a product side III of the dividing wall section from top to bottom, the operation pressure is normal pressure, the control temperatures of sensitive plates N1, N2 and N3 are respectively 80 ℃, 108.6 ℃ and 113.9 ℃, the extraction amounts of a tower top and a side line are respectively controlled to be 27.1g/min and 43.6g/min, the liquid levels of a tower top condensation tank, a liquid collection region and a tower kettle are respectively controlled to be 60%, 60% and 75%, and the control results are shown in table 1. It can be seen that the quality control method related by the invention also achieves ideal control effect after the raw material composition and the structural parameters of the dividing wall tower are replaced.
[ example 3 ]
The ethanol/isobutanol/n-pentanol mixture is used as a raw material, and the composition of the ethanol/isobutanol/n-pentanol mixture is 12.80 percent of ethanol, 70.69 percent of isobutanol and 16.51 percent of n-pentanol in percentage by weight. Taking the feeding flow rate of 80g/min as a reference, separating according to the operation control method of the dividing wall tower shown in figure 1, obtaining an ethanol product at the tower top, obtaining an isobutanol product at the side line, and obtaining an n-pentanol product at the tower bottom. The structural parameters of the dividing wall tower are the same as those of the embodiment 1, the operation pressure is normal pressure, the control temperatures of the sensitive plates N1, N2 and N3 are 77.6 ℃, 105.7 ℃ and 110.2 ℃, the extraction amounts of the top and the side line are respectively controlled to be 10.2g/min and 56.5g/min, the liquid levels of the condensation tank at the top of the tower, the liquid collecting region and the tower kettle are respectively controlled to be 60 percent, 60 percent and 80 percent, and the control results are shown in the table 1. It can be seen that the quality control method of the present invention still achieves the desired control effect after the separator system is replaced.
TABLE 1 control Effect
Comparative example 1
The same dividing wall column and raw material composition as in example 1 were used to conduct separation in accordance with the control method shown in FIG. 2, and the control results are shown in Table 2. It can be seen that, under the control method, in order to ensure that the product purity of the benzene and the toluene is not less than 99.9%, the purity and the yield of the mixed xylene in the tower bottom are difficult to ensure and are only 99.78%, and meanwhile, the stabilization time of the whole tower is longer and exceeds 10 hr; if the heat load of the reboiler of the tower kettle is further increased, the purity of the mixed xylene in the tower kettle can be improved to 99.9 percent, but the pressure difference below the public stripping section and the partition plate is obviously increased at the moment and is increased from 0.5KPa to 3KPa, and the stable operation of the dividing wall tower is damaged.
Comparative example 2
The same dividing wall column and raw material composition as in example 1 were used to conduct separation in accordance with the control method shown in FIG. 3, and the control results are shown in Table 2. It can be seen that under the control method, the purity of benzene and toluene products is obviously lower, especially benzene, because only the temperature of the tower plate at the top of the product side and the liquid phase distribution at the two sides of the partition wall section are controlled, the content of impurity benzene and xylene in the side line products can be effectively controlled, namely the product quality of the side line toluene is controlled, but the product quality of the tower top benzene and the tower bottom xylene cannot be ensured; meanwhile, in the control scheme, because the evaporation capacity or the gas-liquid flow in the tower is not correspondingly controlled, the product yield cannot be effectively controlled, for example, the yield of mixed xylene in the tower kettle is obviously lower, and the stabilization time of the dividing wall tower is relatively longer.
TABLE 2 control Effect of different control schemes
Claims (6)
1. A quality control method of a dividing wall tower comprises the following five control areas:
(1) raw material feeding control area: controlling the raw material feeding amount by adopting a flow controller;
(2) the tower top reflux and extraction control area: controlling the cold energy of a condenser at the top of the tower by adopting a temperature controller, controlling the extraction amount of products at the top of the tower by adopting a flow controller, and controlling the amount of reflux liquid at the top of the tower by adopting a liquid level controller;
(3) liquid collection and distribution control area: controlling the flow of the distillate at the bottom of the public rectification section by adopting a liquid level controller, and controlling the distribution liquid amount at the feed side of the partition section by adopting a temperature controller;
(4) side draw control zone: controlling the side product extraction amount by adopting a flow controller;
(5) the extraction control area of the tower kettle: controlling the heat of a reboiler of the tower kettle by adopting a temperature controller and controlling the product extraction amount of the tower kettle by adopting a liquid level controller;
wherein, the temperature controller in the tower top reflux and extraction control area controls the temperature of a sensitive plate of the public rectifying section of the dividing wall tower, and the cold quantity of the tower top condenser is automatically adjusted according to the temperature of the sensitive plate;
the liquid level controller in the tower top reflux and extraction control area controls the liquid level of the tower top reflux tank, and the flow of the tower top reflux liquid is automatically adjusted according to the liquid level;
the temperature controller in the liquid collection and distribution control area controls the temperature of a sensitive plate at the feeding side of the dividing wall section of the dividing wall tower, and the distribution liquid amount at the feeding side is automatically adjusted according to the temperature of the sensitive plate;
the temperature controller in the tower kettle extraction control area controls the temperature of a sensitive plate of a public stripping section of the dividing wall tower, and the heat of a reboiler of the tower kettle is automatically adjusted according to the temperature of the sensitive plate.
2. The method of claim 1, wherein the flow controller in the feed control zone controls the feed rate of the feed material, and the actual feed rate is automatically adjusted based on the set feed rate.
3. The quality control method of the dividing wall column according to claim 1, characterized in that the flow controller in the reflux and extraction control area at the top of the column controls the extraction amount of the product at the top of the column, the flow rate is set according to the feeding amount of the raw material and the percentage content of the corresponding light component in the feeding composition, and the actual extraction amount of the product at the top of the column is automatically adjusted according to the set extraction amount of the product.
4. The method of claim 1, wherein the liquid level controller in the liquid collection and distribution control section controls the liquid level in the bottom liquid collection section of the common rectifying section of the dividing wall column, and the total flow rate of the bottom distillate liquid is automatically adjusted according to the liquid level.
5. The quality control method of the dividing wall tower according to claim 1, characterized in that the flow controller in the side draw control area controls the side draw amount of the side product, the flow rate is set according to the raw material feeding amount and the percentage content of the corresponding intermediate component in the feeding composition, and the actual side draw amount is automatically adjusted according to the set product draw amount.
6. The method for controlling the quality of a dividing wall tower as claimed in claim 1, wherein the liquid level controller in the tower bottom extraction control area controls the liquid level of the tower bottom of the dividing wall tower, and the extraction amount of the product in the tower bottom is automatically adjusted according to the liquid level.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610831425.6A CN107837554B (en) | 2016-09-19 | 2016-09-19 | Quality control method of dividing wall tower |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610831425.6A CN107837554B (en) | 2016-09-19 | 2016-09-19 | Quality control method of dividing wall tower |
Publications (2)
| Publication Number | Publication Date |
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| CN107837554A CN107837554A (en) | 2018-03-27 |
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| US4230533A (en) * | 1978-06-19 | 1980-10-28 | Phillips Petroleum Company | Fractionation method and apparatus |
| WO2004071618A1 (en) * | 2003-02-12 | 2004-08-26 | Uop Llc | Dividing wall column control system |
| CN101198913A (en) * | 2005-06-15 | 2008-06-11 | 查尔斯·R·卡勒 | Online dynamic advisor from MPC models |
| CN102631791A (en) * | 2012-03-31 | 2012-08-15 | 中国石油化工股份有限公司 | Method for controlling dividing-wall distillation column |
| CN102872609A (en) * | 2011-07-11 | 2013-01-16 | 中国石油化工股份有限公司 | Dividing wall rectifying tower |
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| US4230533A (en) * | 1978-06-19 | 1980-10-28 | Phillips Petroleum Company | Fractionation method and apparatus |
| WO2004071618A1 (en) * | 2003-02-12 | 2004-08-26 | Uop Llc | Dividing wall column control system |
| CN101198913A (en) * | 2005-06-15 | 2008-06-11 | 查尔斯·R·卡勒 | Online dynamic advisor from MPC models |
| CN102872609A (en) * | 2011-07-11 | 2013-01-16 | 中国石油化工股份有限公司 | Dividing wall rectifying tower |
| CN102631791A (en) * | 2012-03-31 | 2012-08-15 | 中国石油化工股份有限公司 | Method for controlling dividing-wall distillation column |
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