阅读说明：本技术 焦油蒸馏装置及蒸馏方法 (Tar distillation device and distillation method ) 是由 罗灿 于 2020-05-08 设计创作，主要内容包括：本发明公开了一种焦油蒸馏装置,原料焦油管路依次通过第一换热器、第一加热器后连接至脱水塔,脱水焦油循环管路通过第二加热器且两端分别与脱水塔连接,脱水焦油管路一端与脱水塔连接,另一端依次通过第二换热器、加热炉后与蒸馏塔连接,软沥青管路一端与连接,另一端依次通过第二换热器、第一换热器分别与脱水焦油管路、原料焦油管路换热,旁通管路的两端分别与第二换热器两侧的软沥青管路相连接,旁通阀设置在旁通管路上。本发明可在出现脱水塔所需能源故障时,保证整个焦油蒸馏装置的正常运行,且可以利用能源价格的变化,对能源的使用进行优化,降低生产成本。本发明还公开了一种采用上述焦油蒸馏装置进行焦油蒸馏的方法。(The invention discloses a tar distillation device, wherein a raw material tar pipeline is connected to a dehydration tower after passing through a first heat exchanger and a first heater in sequence, a dehydration tar circulating pipeline passes through a second heater, two ends of the dehydration tar circulating pipeline are respectively connected with the dehydration tower, one end of the dehydration tar pipeline is connected with the dehydration tower, the other end of the dehydration tar pipeline passes through the second heat exchanger and a heating furnace in sequence and is connected with a distillation tower, one end of a soft asphalt pipeline is connected with the soft asphalt pipeline, the other end of the soft asphalt pipeline passes through the second heat exchanger and the first heat exchanger in sequence and respectively exchanges heat with the dehydration tar pipeline and the raw material tar pipeline, two ends of a bypass pipeline are respectively connected with the. The invention can ensure the normal operation of the whole tar distillation device when the energy fault required by the dehydration tower occurs, can optimize the use of energy by utilizing the change of energy price, and reduces the production cost. The invention also discloses a method for distilling tar by adopting the tar distillation device.)

1. A tar distillation device is characterized by comprising a dehydration tower (1), a heating furnace (2), a distillation tower (3), a first heat exchanger (4), a first heater (5), a second heater (6), a second heat exchanger (7), a raw material tar pipeline (8), a dehydration tar circulation pipeline (9), a dehydration tar pipeline (10), a soft asphalt pipeline (11), a bypass pipeline (12) and a bypass valve (13), wherein the dehydration tower (1) is provided with a raw material tar inlet, a dehydration tar outlet and two dehydration tar circulation ports, the distillation tower (3) is provided with a dehydration tar inlet and a soft asphalt outlet, the raw material tar pipeline (8) is connected with the raw material tar inlet after sequentially passing through the first heat exchanger (4) and the first heater (5), the dehydration tar circulation pipeline (9) is connected with the two dehydration tar circulation ports through the second heater (6) and two ends respectively, dehydration tar pipeline (10) one end and dehydration tar exit linkage, the other end loops through second heat exchanger (7), heating furnace (2) back and dehydration tar entry linkage, maltha pipeline (11) one end and maltha exit linkage, the other end loops through second heat exchanger (7), first heat exchanger (4) respectively with dehydration tar pipeline (10), raw materials tar pipeline (8) heat transfer, the both ends of bypass pipeline (12) are connected with maltha pipeline (11) of second heat exchanger (7) both sides respectively, bypass valve (13) set up the break-make in order to control bypass pipeline (10) on bypass pipeline (10).

2. The tar distillation apparatus according to claim 1, wherein the furnace (2) is a coke oven gas furnace.

3. The tar distillation apparatus according to claim 1 or 2, wherein the first heater (5) is a heat exchanger using low-pressure steam as a heat medium.

4. The tar distillation apparatus according to claim 1 or 2, wherein the second heater (6) is a heat exchanger with medium pressure steam as a heat medium.

5. A method for distillation of tar with the tar distillation apparatus according to any of claims 1 to 4, wherein the raw tar is transported in a raw tar line (8) and, during the transportation, is heated by a first heat exchanger (4) and a first heater (5) in sequence and then enters the dehydration tower (1); dehydrating raw material tar to form dehydrated tar by the dehydrating tower (1), circulating the dehydrated tar at the bottom of the dehydrating tower (1) in a dehydrated tar circulating pipeline (9), and heating by a second heater (6) in the circulating process to maintain the temperature at the bottom of the dehydrating tower (1); the dehydrated tar output by the dehydration tower (1) is conveyed in a dehydrated tar pipeline (10), and is heated by a second heat exchanger (7) and a heating furnace (2) in sequence and then conveyed to a distillation tower (3) for distillation in the conveying process; the high-temperature soft asphalt output by the distillation tower (3) is conveyed in a soft asphalt pipeline (11), and the high-temperature soft asphalt sequentially passes through the second heat exchanger (7) and the first heat exchanger (4) in the conveying process to respectively exchange heat with dehydrated tar in the dehydrated tar pipeline (10) and raw tar in the raw material tar pipeline (8), and then is finally conveyed into a storage tank.

6. The method of distilling tar in accordance with claim 5, wherein the heating amount of the second heater (6) is increased or the bypass valve (13) is opened and the heating amount of the heating furnace (2) is increased if the first heater (5) does not provide a heat source.

7. The method of distilling tar in accordance with claim 5, wherein the heating capacity of the first heater (5) is increased or the bypass valve (13) is opened and the heating capacity of the heating furnace (2) is increased if the second heater (6) does not provide a heat source.

8. The method of distilling tar in accordance with claim 5, wherein the bypass valve (13) is opened and the heating amount of the heating furnace (2) is increased if neither the first heater (5) nor the second heater (6) is providing a heat source.

Technical Field

The invention belongs to the technical field of coal tar processing, and particularly relates to a tar distillation device and a distillation method.

Background

Coal tar is an oil product obtained from coal during high-temperature dry distillation and gasification. In the coking process, high-temperature raw gas is recycled by spraying circulating ammonia water and condensing and cooling a primary cooler, and in addition, the high-pressure ammonia water injection method is adopted for smokeless coal charging, so that a large amount of ammonia water is contained in tar. The dehydration of the coal tar is divided into pre-dehydration and final dehydration, the pre-dehydration technology generally comprises heating and standing and super centrifuge dehydration, and after the pre-dehydration, the water content in the coal tar is reduced to be within 4 percent, generally between 2 and 3 percent. After free water in the coal tar is separated by a super centrifuge and standing, the remaining water exists in a chemical combination state and cannot be removed, and the water content of the coal tar can generate a plurality of adverse effects on the subsequent distillation operation, such as increase of processing energy consumption; the operation system is disturbed; and the corrosive substances are brought along with the moisture, so that the corrosion of pipelines and equipment is caused; the water content of coal tar also has a great influence on the product quality. Therefore, dehydration must be performed before tar processing to enable distillation.

In the final dehydration stage, coal tar processing enterprises generally adopt a dehydration tower to carry out atmospheric distillation dehydration, the method has the advantages of low energy consumption and good dehydration effect, and the moisture of the coal tar can be dehydrated to 0.1-0.2%. When the dehydration tower is used for distillation dehydration of raw material tar, the dehydration tower and a heat source required by the dehydration tower are generally arranged, the raw material tar is heated and then sent into the dehydration tower, and light oil is used as reflux at the tower top. Water and light oil form an azeotropic mixture, the azeotropic mixture escapes from the top of the tower, the azeotropic mixture flows into a separator after being condensed and cooled, and the separated water is discharged; a part of the light oil is returned to the dehydration tower, and a part of the light oil is recovered, thereby reducing the moisture in the tar.

The existing tar production technology has the problems that the dehydration tower and the heat exchange equipment (heating equipment) thereof are determined, the raw material tar cannot be distilled and dehydrated when the energy required by the dehydration tower breaks down and the heat required by the dehydration tower cannot be normally supplied, so that the whole tar processing is influenced, and the shutdown and the production halt of the device are caused.

Disclosure of Invention

In order to solve the technical problems, the invention provides a tar distillation device and a distillation method.

The purpose of the invention is realized by the following technical scheme:

on the one hand, the tar distillation device comprises a dehydration tower, a heating furnace, a distillation tower, a first heat exchanger, a first heater, a second heat exchanger, a raw material tar pipeline, a dehydration tar circulation pipeline, a dehydration tar pipeline, a soft asphalt pipeline, a bypass pipeline and a bypass valve, wherein the dehydration tower is provided with a raw material tar inlet, a dehydration tar outlet and two dehydration tar circulation ports, the distillation tower is provided with a dehydration tar inlet and a soft asphalt outlet, the raw material tar pipeline is connected with the raw material tar inlet after sequentially passing through the first heat exchanger and the first heater, the dehydration tar circulation pipeline is connected with the two dehydration tar circulation ports through the second heater and two ends respectively, one end of the dehydration tar pipeline is connected with the dehydration tar outlet, and the other end of the dehydration tar pipeline is connected with the dehydration tar inlet after sequentially passing through the second heat exchanger and the heating furnace, one end of the soft asphalt pipeline is connected with a soft asphalt outlet, the other end of the soft asphalt pipeline sequentially passes through the second heat exchanger and the first heat exchanger to respectively exchange heat with the dehydrated tar pipeline and the raw material tar pipeline, two ends of the bypass pipeline are respectively connected with the soft asphalt pipelines on two sides of the second heat exchanger, and the bypass valve is arranged on the bypass pipeline to control the on-off of the bypass pipeline.

As a further improvement, the heating furnace is a coke oven gas heating furnace.

As a further improvement, the first heater is a heat exchanger with low-pressure steam as a heat medium.

As a further improvement, the second heater is a heat exchanger with medium-pressure steam as a heat medium.

The invention provides a tar distillation device, which comprises a dehydration tower, a heating furnace, a distillation tower, a first heat exchanger, a first heater, a second heat exchanger, a raw material tar pipeline, a dehydration tar circulation pipeline, a dehydration tar pipeline, a maltha pipeline, a bypass pipeline and a bypass valve, wherein the dehydration tower is provided with a raw material tar inlet, a dehydration tar outlet and two dehydration tar circulation ports, the distillation tower is provided with a dehydration tar inlet and a maltha outlet, the raw material tar pipeline is connected with the raw material tar inlet after passing through the first heat exchanger and the first heater in sequence, the dehydration tar circulation pipeline passes through the second heater, two ends of the dehydration tar circulation pipeline are respectively connected with the two dehydration tar circulation ports, one end of the dehydration tar pipeline is connected with the dehydration tar outlet, the other end of the dehydration tar pipeline passes through the second heat exchanger and the heating, one end of the soft asphalt pipeline is connected with a soft asphalt outlet, the other end of the soft asphalt pipeline sequentially passes through the second heat exchanger and the first heat exchanger to respectively exchange heat with the dehydrated tar pipeline and the raw material tar pipeline, two ends of the bypass pipeline are respectively connected with the soft asphalt pipelines on two sides of the second heat exchanger, and the bypass valve is arranged on the bypass pipeline to control the on-off of the bypass pipeline. The invention can utilize different process flows to supply heat to the dehydrating tower by utilizing other energy sources when the energy source fault required by the dehydrating tower occurs, thereby maintaining the normal operation of the dehydrating tower and further ensuring the normal operation of the whole tar distillation device. In the normal production process, the change of the energy price can be utilized to optimize the use of the energy, thereby reducing the production cost of tar processing and creating profits for enterprises.

On the other hand, the invention also provides a method for distilling tar by adopting the tar distillation device, wherein the raw material tar is conveyed in a raw material tar pipeline, and the raw material tar is heated by the first heat exchanger and the first heater in sequence and then enters the dehydration tower in the conveying process; dehydrating raw material tar by a dehydrating tower to form dehydrated tar, circulating the dehydrated tar at the bottom of the dehydrating tower in a dehydrated tar circulating pipeline, and heating by a second heater in the circulating process to maintain the temperature at the bottom of the dehydrating tower; conveying the dehydrated tar output by the dehydration tower in a dehydrated tar pipeline, heating the dehydrated tar by a second heat exchanger and a heating furnace in sequence in the conveying process, and then conveying the dehydrated tar into a distillation tower for distillation; the high-temperature soft asphalt output by the distillation tower is conveyed in a soft asphalt pipeline, and the high-temperature soft asphalt sequentially passes through the second heat exchanger and the first heat exchanger in the conveying process to respectively exchange heat with dehydrated tar in the dehydrated tar pipeline and raw tar in the raw tar pipeline, and then is conveyed into the storage tank.

As a further improvement, if the first heater does not provide a heat source, the heating amount of the second heater is increased, or the bypass valve is opened and the heating amount of the heating furnace is increased.

As a further improvement, if the second heater does not provide a heat source, the heating quantity of the first heater is increased, or the bypass valve is opened and the heating quantity of the heating furnace is increased.

As a further improvement, if the first heater and the second heater do not provide heat sources, the bypass valve is opened and the heating amount of the heating furnace is increased.

The tar distillation method can utilize different process flows to supply heat to the dehydrating tower by using other energy sources when the energy source needed by the dehydrating tower fails, so that the normal operation of the dehydrating tower is maintained, and the normal operation of the whole tar distillation device is further ensured. In the normal production process, the change of the energy price can be utilized to optimize the use of the energy, thereby reducing the production cost of tar processing and creating profits for enterprises.

Drawings

The invention is further illustrated by means of the attached drawings, but the embodiments in the drawings do not constitute any limitation to the invention, and for a person skilled in the art, other drawings can be obtained on the basis of the following drawings without inventive effort.

FIG. 1 is a schematic view showing the structure of a tar distillation apparatus according to the present invention.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the following detailed description of the present invention is provided with reference to the accompanying drawings and specific embodiments, and it is to be noted that the embodiments and features of the embodiments of the present application can be combined with each other without conflict.

The core of the invention is to provide a tar distillation device and a distillation method, in the tar distillation device, different tar processing production flows are formed by switching various energy sources, the production stability of the tar distillation device can be improved, the normal production can be maintained when the steam energy source fails, and the production cost of the tar processing device can be reduced by optimizing the use of various energy sources.

Referring to fig. 1, a tar distillation apparatus according to an embodiment of the present invention includes a dehydration tower 1, a heating furnace 2, a distillation tower 3, a first heat exchanger 4, a first heater 5, a second heater 6, a second heat exchanger 7, a raw material tar pipeline 8, a dehydrated tar circulation pipeline 9, a dehydrated tar pipeline 10, a soft pitch pipeline 11, a bypass pipeline 12, and a bypass valve 13. The heating furnace 2 is a coke oven gas heating furnace, the first heater 5 is a heat exchanger using low-pressure steam as a heat medium, and the second heater 6 is a heat exchanger using medium-pressure steam as a heat medium. The dehydration tower 1 is provided with a raw material tar inlet, a dehydrated tar outlet and two dehydrated tar circulation ports, the distillation tower 3 is provided with a dehydrated tar inlet and a maltha outlet, a raw material tar pipeline 8 is connected with the raw material tar inlet after sequentially passing through a first heat exchanger 4 and a first heater 5, the dehydrated tar circulation pipeline 9 is respectively connected with the two dehydrated tar circulation ports through a second heater 6 and two ends, one end of the dehydrated tar pipeline 10 is connected with the dehydrated tar outlet, the other end of the dehydrated tar pipeline sequentially passes through a second heat exchanger 7 and a heating furnace 2 and then is connected with the dehydrated tar inlet, one end of the maltha pipeline 11 is connected with the maltha outlet, the other end of the maltha pipeline sequentially passes through the second heat exchanger 7 and the first heat exchanger 4 and respectively exchanges heat with the dehydrated tar pipeline 10 and the raw material tar pipeline 8, and two ends of a bypass pipeline 12 are respectively, the bypass valve 13 is disposed on the bypass line 10 to control the opening and closing of the bypass line 10.

According to the tar distillation device provided by the embodiment of the invention, in the normal production process, raw material tar is conveyed in the raw material tar pipeline 8, and the raw material tar is sequentially subjected to heat exchange with soft asphalt through the first heat exchanger 4 in the conveying process, and then is subjected to heat exchange with low-pressure steam through the first heater 5 and then is sent into the dehydration tower 1; dehydrating raw material tar to form dehydrated tar in the dehydrating tower 1, circulating the dehydrated tar at the bottom of the dehydrating tower 1 in a dehydrated tar circulating pipeline 9, and exchanging heat with medium-pressure steam through a second heater 6 in the circulating process to maintain the temperature at the bottom of the dehydrating tower 1 and provide required heat for the dehydrating tower; the dehydrated tar output by the dehydration tower 1 is conveyed in a dehydrated tar pipeline 10, and in the conveying process, the dehydrated tar exchanges heat with high-temperature soft asphalt from the bottom of the distillation tower 3 through a second heat exchanger 7, and then is sent into the heating furnace 2 for heating and warming, and is sent into the distillation tower 3 for tar distillation after reaching a certain temperature; after the tar is distilled in the distillation tower 3, the high-temperature soft asphalt output by the distillation tower 3 is conveyed in a soft asphalt pipeline 11, and the high-temperature soft asphalt sequentially passes through the second heat exchanger 7 and the first heat exchanger 4 in the conveying process to respectively exchange heat with the dehydrated tar in the dehydrated tar pipeline 10 and the raw material tar in the raw material tar pipeline 8, and then is finally conveyed into a storage tank.

In the normal production flow, the heat source required by dehydration of the dehydration tower is provided by medium-pressure steam, the heat source required by distillation of the distillation tower is provided by coke oven gas, and the raw material tar and the dehydrated tar can be preheated by heat exchange of high-temperature maltha so as to save energy. When the first heater (low-pressure steam) and/or the second heater (medium-pressure steam) do not provide heat source due to failure, the bypass valve can be opened, and the heating quantity of the heating furnace is properly increased to supply heat to the dehydration tower, so that the normal operation of the dehydration tower is maintained, and the normal operation of the whole tar distillation device is further ensured. In the normal production process, the use amount of 3 energy sources can be adjusted according to the price changes of low-pressure steam, medium-pressure steam and coke oven gas, so that the aim of reducing the production cost is fulfilled, and the profit is created for enterprises.

The embodiment of the invention also provides a method for distilling tar by adopting the tar distilling device, when the atmospheric and vacuum tar is processed and normally produced, the raw material tar is conveyed in the raw material tar pipeline 8, the raw material tar is heated by the first heat exchanger 4 and the first heater 5 in sequence and then enters the dehydrating tower 1 in the conveying process, the temperature of the raw material tar is about 85 ℃, the raw material tar is heated to 150 ℃ before entering the dehydrating tower after heat exchange is carried out by the first heat exchanger 4 and the first heater 5; dehydrating raw material tar to form dehydrated tar in a dehydrating tower 1, circulating the dehydrated tar at the bottom of the dehydrating tower 1 in a dehydrated tar circulating pipeline 9, heating the dehydrated tar by a second heater 6 in the circulating process to maintain the temperature of the bottom of the dehydrating tower 1, circulating the dehydrated tar at the bottom of the dehydrating tower, heating the tar to 200 ℃ by the second heater 6, returning the heated tar to the dehydrating tower, and maintaining the temperature of the bottom of the dehydrating tower to be 190-200 ℃; the dehydrated tar output by the dehydrating tower 1 is conveyed in a dehydrated tar pipeline 10, the dehydrated tar is heated by a second heat exchanger 7 and a heating furnace 2 in sequence and then sent to a distillation tower 3 for distillation in the conveying process, and the dehydrated tar is heated to 345 ℃ and sent to the distillation tower for distillation; the high-temperature soft asphalt output by the distillation tower 3 is conveyed in a soft asphalt pipeline 11, and after heat exchange with the dehydrated tar in the dehydrated tar pipeline 10 and the raw tar in the raw tar pipeline 8 respectively sequentially through the second heat exchanger 7 and the first heat exchanger 4 in the conveying process, the soft asphalt with the extraction temperature of about 130 ℃ is finally sent into a storage tank.

When the switching use of three energy sources needs to be adjusted due to faults or energy source price, the detailed process flow is as follows:

1. the low-pressure steam cannot be supplied. If the low-pressure steam can not be supplied (the first heater 5 does not provide a heat source), the temperature of the raw material tar entering the dehydration tower can be reduced to 130-140 ℃, the supply amount of the medium-pressure steam can be slightly increased (the heating amount of the second heater 6 is increased), and the temperature of the bottom of the dehydration tower is kept at 190-200 ℃; or the bypass valve 13 is opened, the bypass pipeline is conducted, heat exchange between the high-temperature maltha and the dehydrated tar in the second heat exchanger 7 is reduced, and the temperature of the fed maltha of the first heat exchanger 4 is increased, so that the temperature of the raw material tar discharged from the first heat exchanger 4 is increased to about 150 ℃, and the feeding temperature of the dehydrating tower is kept unchanged; at this time, in order to maintain the feed temperature of the distillation tower at about 345 ℃, the consumption of the coke oven gas is slightly increased (the heating amount of the heating furnace 2 is increased);

2. medium pressure steam cannot be supplied (the second heater 6 does not provide a heat source). When the medium-pressure steam can not be supplied, the bypass valve 13 is opened, the bypass pipeline is conducted, the heat exchange between the high-temperature maltha and the dehydrated tar in the second heat exchanger 7 is reduced, the temperature of the fed maltha of the first heat exchanger 4 is increased, the temperature of the raw material tar out of the first heat exchanger 4 is increased to about 160 ℃, and the feeding temperature of the dehydration tower is kept unchanged; or, the supply amount of low-pressure steam is increased (the heating amount of the first heater 4 is increased), the feeding temperature of the dehydrating tower is increased to about 160 ℃, the operation mode of the dehydrating tower is changed into a one-time flash evaporation mode from distillation, and meanwhile, the top reflux of the dehydrating tower is adjusted, so that the dehydrating effect of the raw material tar is ensured; at this time, in order to ensure that the temperature of the dehydrated tar entering the distillation tower is maintained to be about 345 ℃, the consumption of the coke oven gas is increased (the heating quantity of the heating furnace 2 is increased);

3. when low-pressure steam and medium-pressure steam can not be supplied (the first heater 5 and the second heater 6 do not provide heat sources), the bypass valve 13 is opened, the bypass pipeline is conducted, the heat exchange between high-temperature soft asphalt and dehydrated tar in the second heat exchanger 7 is reduced, the temperature of the fed soft asphalt of the first heat exchanger 4 is increased, the tower inlet temperature of raw material tar is raised to about 160 ℃ through the first heat exchanger 4, meanwhile, the tower top reflux of the dehydration tower is adjusted, and the primary flash evaporation dehydration effect of the raw material tar is ensured; because the heat exchange quantity of the dehydrated tar and the high-temperature maltha is reduced, in order to ensure the temperature of the dehydrated tar entering the distillation tower, the consumption of the coke oven gas is correspondingly increased (the heating quantity of the heating furnace 2 is increased), and the temperature of the dehydrated tar entering the distillation tower is maintained to be about 345 ℃.

According to the method for distilling the tar by adopting the tar distilling device, provided by the embodiment of the invention, when the first heater and/or the second heater do not provide a heat source due to a fault, the bypass valve can be opened, and the heating quantity of the heating furnace is properly increased to supply heat to the dehydrating tower, so that the normal operation of the dehydrating tower is maintained, and the normal operation of the whole tar distilling device is further ensured. In the normal production process, the use amount of 3 energy sources can be adjusted according to the price changes of low-pressure steam, medium-pressure steam and coke oven gas, so that the aim of reducing the production cost is fulfilled, and the profit is created for enterprises.

In the description above, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore should not be construed as limiting the scope of the present invention.

In conclusion, although the present invention has been described with reference to the preferred embodiments, it should be noted that, although various changes and modifications may be made by those skilled in the art, they should be included in the scope of the present invention unless they depart from the scope of the present invention.