阅读说明：本技术 一种高品质浸渍沥青生产方法 (Production method of high-quality impregnating asphalt ) 是由 杜亚平 陈年连 苏绕宁 张子昂 于 2019-11-06 设计创作，主要内容包括：本发明涉及煤化工领域,具体提供一种高品质浸渍沥青生产方法。焦油通过二级换热至一定温度,使其达到较低的粘度和较好的流动性,降低其密度,通过具有较高分离因素的碟式离心机进行分离,离心机定期排渣,排渣间歇的设定须使渣相有较好的流动性,防止堵塞碟片和渣腔。离心净化后的焦油经蒸馏并适当控制参数,以达到高品质浸渍沥青的软化点、甲苯不溶物、喹啉不溶物、结焦值、灰分等要求。(The invention relates to the field of coal chemical industry, and particularly provides a production method of high-quality impregnated asphalt. The tar is subjected to secondary heat exchange to a certain temperature, so that the tar reaches lower viscosity and better fluidity, the density of the tar is reduced, the tar is separated by a disc centrifuge with higher separation factors, the centrifuge periodically discharges slag, and the slag phase needs to have better fluidity by setting the slag discharge interval, so that the disc and the slag cavity are prevented from being blocked. The tar after centrifugal purification is distilled and parameters are properly controlled to meet the requirements of high-quality dipping asphalt on softening point, toluene insoluble substances, quinoline insoluble substances, coking value, ash content and the like.)

1. The production method of the high-quality impregnated asphalt is characterized by comprising the following steps:

(1) the tar is pumped out from the raw material tank, sent to a first-stage heat exchanger, exchanges heat with the tar at the outlet of the disc centrifuge to 90-120 ℃, exchanges heat with steam through a second-stage heat exchanger to 95-180 ℃, and enables the tar to reach the viscosity of 2-30 mPa.S and the density of 1.05-1.13 g/cm³So that the chassis of the sliding rotary drum can be normally closed under the action of water pressure and a spring;

(2) after the temperature of the secondary tar heat exchange outlet rises to 95 ℃, an electric three-way valve is automatically switched into a disc centrifuge, and two phases are separated by the disc centrifuge, wherein the rotating speed of a rotary drum is 7000-9000 rpm, the separation factor is 8000-14000, and the disc interval is 0.3-0.6 mm;

(3) the disc centrifuge discharges slag for 5-30 min regularly to prevent the disc and slag cavity from being blocked, and the slag is matched into a tar production system for producing medium-temperature asphalt or modified asphalt so as to improve the QI content index;

(4) the tar at the outlet of the disc centrifuge keeps a certain backpressure of 0.1-0.2 MPa, exchanges heat with the tar from a raw material tank in a primary heat exchanger, is cooled to a safe temperature of 70-95 ℃, and enters a clean tar storage tank;

(5) the QI content of the centrifugally purified tar is less than or equal to 0.2%, the yield is 80-96%, and the tar is distilled at 380-400 ℃ and the asphalt stays at the bottom of the tower for 30-60 min to obtain high-quality impregnated asphalt.

2. The method for producing high-quality impregnated asphalt according to claim 1, wherein: when the temperature of the tar secondary heat exchange outlet is less than 95 ℃ in the startup temperature rise stage, the electric three-way valve is used for bypassing and cutting into the underground tank.

3. The method for producing high-quality impregnated asphalt according to claim 1, wherein: the high-quality impregnating asphalt: a softening point of 86-94 ℃, toluene insoluble 10-12%, quinoline insoluble 0.2-0.4%, a coking value of 47-48%, an ash content of 0.05-0.06%, etc.

4. The method for producing high-quality impregnated asphalt according to claim 1, wherein: in the step (1), the flow of the tar is 1-5 m³The reaction mixture is withdrawn from the raw material tank.

5. The method for producing high-quality impregnated asphalt according to claim 1, wherein: in the step (1), the content of tar QI is 0.5-2.0%.

6. The method for producing high-quality impregnated asphalt according to claim 1, wherein: the purified tar with the QI content of less than or equal to 0.2 percent is prepared by the following steps:

(1) the tar is pumped out from the raw material tank, sent to a first-stage heat exchanger, exchanges heat with the tar at the outlet of the disc centrifuge to 90-120 ℃, exchanges heat with steam through a second-stage heat exchanger to 95-180 ℃, and enables the tar to reach the viscosity of 2-30 mPa.S and the density of 1.05-1.13 g/cm³So that the chassis of the sliding rotary drum can be normally closed under the action of water pressure and a spring;

(2) after the temperature of the secondary tar heat exchange outlet rises to 95 ℃, an electric three-way valve is automatically switched into a disc centrifuge, and two phases are separated by the disc centrifuge, wherein the rotating speed of a rotary drum is 7000-9000 rpm, the separation factor is 8000-14000, and the disc interval is 0.3-0.6 mm;

(3) the disc centrifuge discharges slag for 5-30 min regularly to prevent the disc and slag cavity from being blocked, and the slag is matched into a tar production system for producing medium-temperature asphalt or modified asphalt so as to improve the QI content index;

(4) the tar at the outlet of the disc centrifuge keeps a certain backpressure of 0.1-0.2 MPa, exchanges heat with the tar from a raw material tank in a primary heat exchanger, is cooled to a safe temperature of 70-95 ℃, and enters a clean tar storage tank; the QI content of the obtained centrifugally purified tar is less than or equal to 0.2 percent, and the yield is 80-96 percent.

7. The method for producing high-quality impregnated asphalt according to claim 6, wherein: when the temperature of the tar secondary heat exchange outlet is less than 95 ℃ in the startup temperature rise stage, the electric three-way valve is used for bypassing and cutting into the underground tank.

8. The method for producing high-quality impregnated asphalt according to claim 6, wherein: in the step (1), the flow of the tar is 1-5 m³The reaction mixture is withdrawn from the raw material tank.

9. The method for producing high-quality impregnated asphalt according to claim 6, wherein: in the step (1), the content of tar QI is 0.5-2.0%.

Technical Field

The invention relates to the field of coal chemical industry, in particular to a production method of high-quality impregnated asphalt.

Background

Impurities represented by native QI in coal tar seriously hinder the preparation of high-quality high-value-added coal pitch products, such as impregnant pitch, needle coke, mesophase pitch, pitch-based carbon fiber, spherical activated carbon and the like, and the coal tar or the coal pitch needs to be purified. QI particles are very small, with an average particle size of about 1 μm, and are therefore relatively difficult to remove. The purification method mainly comprises the following steps: standing and settling, filtering, centrifuging, solvent method, and vacuum distilling. The solvent method is classified into a solvent-settling method, a solvent-centrifugation method, a solvent-filtration method, a solvent-flocculation method, a solvent-extraction method, and the like. Wherein: (1) the standing sedimentation separation equipment has small investment and simple process. But the purifying effect is poor, and the QI content is more than 1 percent; (2) the hot melt filtration purification effect is good, but the requirement on the filter screen is strict, frequent manual cleaning is needed, and the operation cost is high; (3) the high-temperature centrifugal separation purification effect is good, but the high-temperature centrifugal separation purification effect stays in an experimental application stage, and industrial application is not seen; (4) the solvent method has good purification effect, but needs to increase a storage tank and distillation equipment, so the investment is large, the solvent consumption is large, the yield of purified asphalt is low, and the process energy consumption is large; (5) the vacuum distillation method has low yield of purified asphalt and large process energy consumption. Therefore, the economic and effective coal tar purification treatment method is to be further developed and researched to create conditions for the expansion of the coal tar deep processing field and the development of high-quality carbon materials (materials).

Shenbaoyi et al (Industrial test of needle coke raw material by centrifugation, fuel and chemical industry, 1994, 25(2): 78-81) conducted research on removing QI from tar by gravity pre-settling and centrifugal separation, and indicated that the appropriate conditions are 7500r/min of three-phase separator rotation speed, 1min of retention time, 80 ℃ of tar temperature, less than or equal to 0.1% of QI content in purified tar and 70% -75% of yield of clean tar. The requirement of preparing high-quality needle coke is met, but the yield is low, and the method only stays in pilot plant research; when a two-phase separator is adopted, the rotating speed is 7500r/min, the retention time is 2min, the tar temperature is 80 ℃, and the QI content in the purified tar is less than or equal to 0.8 percent, which can not meet the requirement of separating needle coke raw materials. And in the two-phase separation operation, the QI accumulated in the slag cavity is large, the residue is very viscous, the slag is difficult to remove, and the two-phase separation operation is difficult to apply industrially.

Patent CN201210307558.5 discloses a pretreatment method of coal tar, which is mainly to remove metals, solid impurities and the like in the coal tar by ultrasonic dehydration under the catalysis of PR-101 type demulsifier and TJ-201 type demetallizing agent, then remove the remaining solid impurities in the coal tar by automatic back washing filter to obtain purified coal tar, and recover the oil slurry discharged after purification by pressure filtration to improve the purification rate of the coal tar, so that the water content in the purified coal tar is less than 0.2%, the metals are less than 10 μ g/g, the solid impurities are less than 0.2%, and the purification rate of the coal tar is more than 95%.

The industrial production process of high-quality impregnating asphalt mainly adopts a solvent method, and generally selects washing oil, kerosene and the like as mixed solvents. CN200810038494.7 discloses a production process of impregnant asphalt. Preparing a mixed solvent by selecting an aliphatic hydrocarbon solvent and an aromatic hydrocarbon solvent; the medium temperature coal pitch or coal tar soft pitch and the mixed solvent enter at least three stages of mixers according to a certain proportion, and enter an extraction tower for separation after being fully mixed; extracting and separating light-phase asphalt and heavy-phase asphalt with low quinoline insoluble content in an extraction tower; and stripping the light-phase asphalt in a stripping tower to obtain impregnant asphalt. Because a mixed solvent is needed and the light phase (containing the solvent) is subjected to secondary distillation, the process is complex and the energy consumption is high.

Disclosure of Invention

The invention aims to provide a production method of high-quality impregnated asphalt. The tar is subjected to secondary heat exchange to a certain temperature, so that the tar reaches lower viscosity and better fluidity, the density of the tar is reduced, the tar is separated by a disc centrifuge with higher separation factors, the centrifuge periodically discharges slag, and the slag phase needs to have better fluidity by setting the slag discharge interval, so that the disc and the slag cavity are prevented from being blocked. The tar after centrifugal purification is distilled and parameters are properly controlled to meet the requirements of high-quality dipping asphalt on softening point, toluene insoluble substances, quinoline insoluble substances, coking value, ash content and the like.

The technical scheme of the invention is as follows:

a production method of high-quality impregnated asphalt comprises the following steps:

(1) the tar is pumped out from the raw material tank and sent to a first-stage heat exchanger and the tar at the outlet of a disc centrifugeThe heat exchange is carried out to 90-120 ℃, the heat exchange is carried out with steam to 95-180 ℃ through a secondary heat exchanger, so that the viscosity is 2-30 mPa.S, and the density is 1.05-1.13 g/cm³So that the chassis of the sliding rotary drum can be normally closed under the action of water pressure and a spring;

(2) after the temperature of the secondary tar heat exchange outlet rises to 95 ℃, an electric three-way valve is automatically switched into a disc centrifuge, and two phases are separated by the disc centrifuge, wherein the rotating speed of a rotary drum is 7000-9000 rpm, the separation factor is 8000-14000, and the disc interval is 0.3-0.6 mm;

(3) the disc centrifuge discharges slag for 5-30 min regularly to prevent the disc and slag cavity from being blocked, and the slag is matched into a tar production system for producing medium-temperature asphalt or modified asphalt so as to improve the QI content index;

(4) the tar at the outlet of the disc centrifuge keeps a certain backpressure of 0.1-0.2 MPa, exchanges heat with the tar from a raw material tank in a primary heat exchanger, is cooled to a safe temperature of 70-95 ℃, and enters a clean tar storage tank;

(5) the QI content of the centrifugally purified tar is less than or equal to 0.2 percent, the yield is 80-96 percent, the tar is distilled at 380-400 ℃, and the pitch stays at the bottom of the tower for 30-60 min so as to meet the requirements of the high-quality dipped pitch on softening point, toluene insoluble substances, quinoline insoluble substances, coking value, ash content and the like.

According to the production method of the high-quality impregnated asphalt, when the temperature of the secondary heat exchange outlet of the tar is not up to 95 ℃ in the startup temperature rise stage, the underground tank is cut in by bypassing the electric three-way valve.

Further, the high quality impregnating pitch: a softening point of 86-94 ℃, toluene insoluble 10-12%, quinoline insoluble 0.2-0.4%, a coking value of 47-48%, an ash content of 0.05-0.06%, etc.

Further, the flow rate of the tar in the step (1) is 1-5 m³The reaction mixture is withdrawn from the raw material tank.

According to the production method of the high-quality impregnated asphalt, the QI content of tar in the step (1) is 0.5-2.0%.

The invention also provides purified tar with the QI content of less than or equal to 0.2 percent, which is prepared by the following steps:

(1) the tar is pumped out from the raw material tank and sent to a first-stage heat exchanger,exchanging heat with tar at the outlet of the disc centrifuge to 90-120 ℃, exchanging heat with steam through a secondary heat exchanger to 95-180 ℃, and enabling the tar to reach the viscosity of 2-30 mPa.S and the density of 1.05-1.13 g/cm³So that the chassis of the sliding rotary drum can be normally closed under the action of water pressure and a spring;

(2) after the temperature of the secondary tar heat exchange outlet rises to 95 ℃, an electric three-way valve is automatically switched into a disc centrifuge, and two phases are separated by the disc centrifuge, wherein the rotating speed of a rotary drum is 7000-9000 rpm, the separation factor is 8000-14000, and the disc interval is 0.3-0.6 mm;

(3) the disc centrifuge discharges slag for 5-30 min regularly to prevent the disc and slag cavity from being blocked, and the slag is matched into a tar production system for producing medium-temperature asphalt or modified asphalt so as to improve the QI content index;

(4) the tar at the outlet of the disc centrifuge keeps a certain backpressure of 0.1-0.2 MPa, exchanges heat with the tar from a raw material tank in a primary heat exchanger, is cooled to a safe temperature of 70-95 ℃, and enters a clean tar storage tank; the QI content of the obtained centrifugally purified tar is less than or equal to 0.2 percent, and the yield is 80-96 percent.

And further, when the temperature of the secondary heat exchange outlet of the tar is not up to 95 ℃ in the startup temperature rise stage, the secondary heat exchange outlet is cut into the underground tank through a bypass of an electric three-way valve.

Further, the flow rate of the tar in the step (1) is 1-5 m³The reaction mixture is withdrawn from the raw material tank.

Further, the content of tar QI in the step (1) is 0.5-2.0%.

Detailed description of the invention:

1. the flow rate is 1-5 m³Extracting tar with a content of 0.5-2.0% per hour (QI) from the raw material tank, conveying the tar to a first-stage heat exchanger, exchanging heat with the tar at the outlet of the disc centrifuge to 90-120 ℃, exchanging heat with steam to 95-180 ℃ through a second-stage heat exchanger, and enabling the tar to reach a viscosity of 2-30 mPa.S and a density of 1.05-1.13 g/cm³So that the chassis of the sliding rotary drum can be normally closed under the action of water pressure and a spring;

2. when the temperature of the tar secondary heat exchange outlet is lower than 95 ℃ in the startup temperature rise stage, the electric three-way valve is used for bypassing and cutting into the underground tank;

3. after the temperature of the secondary tar heat exchange outlet rises to 95 ℃, an electric three-way valve is automatically switched into a disc centrifuge, and two phases are separated by the disc centrifuge, wherein the rotating speed of a rotary drum is 7000-9000 rpm, the separation factor is 8000-14000, and the disc interval is 0.3-0.6 mm;

4. the disc centrifuge discharges slag for 5-30 min regularly to prevent the disc and slag cavity from being blocked, and the slag is matched into a tar production system for producing medium-temperature asphalt or modified asphalt so as to improve the QI content index;

5. the tar at the outlet of the disc centrifuge keeps a certain backpressure of 0.1-0.2 MPa, exchanges heat with the tar from a raw material tank in a primary heat exchanger, is cooled to a safe temperature of 70-95 ℃, and enters a clean tar storage tank;

6. the QI content of the centrifugally purified tar is less than or equal to 0.2 percent, the yield is 80-96 percent, the tar is distilled at 380-400 ℃, and the pitch stays at the bottom of the tower for 30-60 min so as to meet the requirements of the high-quality dipped pitch on softening point, toluene insoluble substances, quinoline insoluble substances, coking value, ash content and the like.

The method has the advantages that the QI removal of tar can be realized only by a short-process centrifugal separation principle, the safety is improved, and the energy consumption is greatly reduced. The QI particles in the tar are separated out by heating the tar to a certain temperature and under the action of high separation factors of a disc centrifuge. Because the slag has good fluidity, the slag can be directly mixed with tar to improve the quality of the modified asphalt, and the effective utilization of resources is realized; the purified tar with the QI content of less than or equal to 0.2 percent is used for producing high-quality impregnated asphalt with the QI content of less than or equal to 0.5 percent. When the product is used for producing downstream carbon products, the permeability of the impregnation process after roasting is obviously improved, and the volume density, the mechanical strength, the conductivity and the like of the graphite products are improved.

Drawings

FIG. 1 is a flow chart of the high quality pitch impregnation process of the present invention.

Description of reference numerals: 1-tar pump, 2-flowmeter, 3-first-stage heat exchanger, 4-disk centrifuge, 4-1-sliding drum chassis, 4-2-drum, 4-3-disk, 5-second-stage heat exchanger, 6-electric three-way valve, 7-underground tank, 8-one-way valve, 9-clean tar storage tank, 10-heating furnace, 11-distillation tower.

Detailed Description

The following describes in detail a specific embodiment of the present invention with reference to the drawings of the embodiment.

The invention relates to a production method of high-quality impregnating asphalt. The tar is pumped out from the raw material tank by a tar pump 1, and the flow of a flow meter 2 is controlled to be 1-5 m³The mixture is sent to a first-stage heat exchanger 3 to exchange heat with the tar at the outlet of the disc centrifuge 4 to 90-120 ℃, and then is subjected to heat exchange with steam to 95-180 ℃ through a second-stage heat exchanger 5, so that the viscosity of the mixture reaches 2-30 mPa.S, and the density of the mixture reaches 1.05-1.13 g/cm³When in normal operation, the sliding drum chassis 4-1 is supported and closed by the water pressure and the spring action; when the temperature of the tar secondary heat exchange outlet is lower than 95 ℃ in the startup temperature rise stage, the electric three-way valve 6 is used for bypassing and cutting into the underground tank 7; after the temperature of the secondary tar heat exchange outlet rises to 95 ℃, an electric three-way valve 6 is automatically switched into a disc centrifuge 4, two phases are separated by the disc centrifuge 4, the rotating speed of a rotary drum 4-2 is 7000-9000 rpm, the separation factor is 8000-14000, the interval of discs 4-3 is 0.3-0.6 mm, QI particles are settled on a group of discs by centrifugal force and enter a slag cavity; the disc centrifuge discharges slag once every 5-30 min according to the setting, so as to prevent the disc and the slag cavity from being blocked, the slag phase is discharged into an underground tank 7, and then the slag phase is matched with a tar production system to be used for producing medium-temperature asphalt or modified asphalt, so that indexes such as QI content, coking value and the like are improved; the tar at the outlet of the disc centrifuge 4 keeps a certain backpressure of 0.1-0.2 MPa, exchanges heat with the tar in the primary heat exchanger 3 through the one-way valve 8 and the raw material tank, is cooled to a safe temperature of 70-95 ℃, and enters a clean tar storage tank 9; stopping tar feeding when the disc centrifuge stops working, and cutting into washing oil for cleaning; the QI content of the centrifugally purified tar is less than or equal to 0.2%, the yield is 80-96%, the tar is heated to 380-400 ℃ by a heating furnace 10, and the tar stays at the bottom of a distillation tower 11 for 30-60 min to meet the requirements of the high-quality dipped asphalt on the softening point of 86-94 ℃, the toluene insoluble substance of 10-12%, the quinoline insoluble substance of 0.2-0.4%, the coking value of 47-48%, the ash content of 0.05-0.06% and the like.

The first embodiment is as follows:

the tar is pumped out from the raw material tank by a tar pump 1, and the flow of the tar is controlled to be 5m by a flow meter 2³H, sending the steam to the primary heat exchanger 3, exchanging heat with steam to 90 ℃ through the secondary heat exchanger 5, and cutting into the underground tank 7 through bypassing of the electric three-way valve 6; temperature rise at outlet of secondary heat exchange of tarUp to 95 ℃ with a viscosity of 30mPa.S and a density of 1.13g/cm³The electric three-way valve 6 is automatically cut into the disc centrifuge 4, and the sliding drum chassis 4-1 is lifted and closed in normal operation; performing two-phase separation by a disc centrifuge 4, wherein the rotating speed of a rotary drum 4-2 is 9000rpm, the separation factor is 14000, the interval of discs 4-3 is 0.6mm, QI particles are settled on a group of discs by centrifugal force and enter a slag cavity; the disc centrifuge discharges slag once every 5min according to the setting, the slag phase is discharged into an underground tank 7 and then is matched into a tar production system for producing medium temperature asphalt, so that indexes such as QI content, coking value and the like of the medium temperature asphalt are improved; the tar at the outlet of the disc centrifuge 4 keeps a certain backpressure of 0.1MPa, the tar exchanges heat in the primary heat exchanger 3 through the one-way valve 8 and the raw material tank, the temperature of the raw material tar after primary heat exchange is 80 ℃, the purified tar is cooled to the safe temperature of 70 ℃, and the purified tar enters a purified tar storage tank 9; stopping tar feeding when the disc centrifuge stops working, and cutting into washing oil for cleaning; the centrifugally purified tar QI content is 0.2%, the yield is 80%, the tar is heated to 380 ℃ by a heating furnace 10 and stays at the bottom of a distillation tower 11 for 30min to obtain the high-quality dipped asphalt with the softening point of 86 ℃, the toluene insoluble substance of 10%, the quinoline insoluble substance of 0.4%, the coking value of 47% and the ash content of 0.05%.

Table 1 examples operating parameters and physical Properties

Example two:

the tar is pumped out from the raw material tank by a tar pump 1, and the flow of the tar is controlled to be 3m by a flow meter 2³H, the mixture is sent to a first-stage heat exchanger 3 to exchange heat with the tar at the outlet of a disc centrifuge 4 to 90 ℃, and then is subjected to heat exchange with steam to 130 ℃ through a second-stage heat exchanger 5, the viscosity is 8mPa.S, and the density is 1.08g/cm³The electric three-way valve 6 is automatically cut into the disc centrifuge 4, and the sliding drum chassis 4-1 is lifted and closed; two-phase separation is carried out by a disk centrifuge 4, the rotating speed of a rotating drum 4-2 is 8000rpm, the separation factor is 10000, the intermittence of a disk 4-3 is 0.4mm,QI particles enter the slag cavity by centrifugal force; the disc centrifuge discharges slag once every 15min according to the setting, the slag phase is discharged into an underground tank 7 and then is matched into a tar production system for producing modified asphalt, so that indexes such as QI content, coking value and the like of the modified asphalt are improved; the tar at the outlet of the disc centrifuge 4 keeps a certain backpressure of 0.15MPa, exchanges heat with the raw material tank through the one-way valve 8 in the primary heat exchanger 3, is cooled to a safe temperature of 85 ℃, and enters a clean tar storage tank 9; the centrifugally purified tar QI content is 0.15%, the yield is 92%, the tar is heated to 390 ℃ by a heating furnace 10 and stays at the bottom of a distillation tower 11 for 40min to obtain the high-quality dipped asphalt with the softening point of 89 ℃, toluene insoluble substances of 11%, quinoline insoluble substances of 0.3%, coking value of 47% and ash content of 0.06%.

Example three:

the tar is pumped out from the raw material tank by a tar pump 1, and the flow of the tar is controlled to be 1m by a flow meter 2³H, the mixture is sent to a first-stage heat exchanger 3 to exchange heat with the tar at the outlet of a disc centrifuge 4 to 120 ℃, and then is subjected to heat exchange with steam to 180 ℃ through a second-stage heat exchanger 5, the viscosity is 2mPa.S, and the density is 1.05g/cm³The electric three-way valve 6 is automatically cut into the disc centrifuge 4, and the sliding drum chassis 4-1 is lifted and closed; performing two-phase separation by a disc centrifuge 4, wherein the rotating speed of a rotating drum 4-2 is 7000rpm, the separation factor is 8000, the interval of a disc 4-3 is 0.3mm, and QI particles enter a slag cavity by centrifugal force; the disc centrifuge discharges slag once every 30min according to the setting, the slag phase is discharged into an underground tank 7 and then is matched into a tar production system for producing modified asphalt, so that indexes such as QI content, coking value and the like of the modified asphalt are improved; the tar at the outlet of the disc centrifuge 4 keeps a certain backpressure of 0.2MPa, exchanges heat with the raw material tank through the one-way valve 8 in the primary heat exchanger 3, is cooled to a safe temperature of 95 ℃, and enters a clean tar storage tank 9; the centrifugally purified tar QI content is 0.1%, the yield is 96%, the tar is heated to 400 ℃ by a heating furnace 10, and the tar stays at the bottom of a distillation tower 11 for 60min to obtain the high-quality dipped asphalt with the softening point of 94 ℃, the toluene insoluble substance of 12%, the quinoline insoluble substance of 0.2%, the coking value of 48% and the ash content of 0.05%.

The operating parameters and physical properties of the examples are shown in Table 1.