Heteroatom-containing high-softening-point asphalt as well as continuous preparation method and production system thereof

Abstract

The invention provides heteroatom-containing high-softening-point asphalt and a continuous preparation method and a production system thereof, and the method comprises the following steps: heating and melting asphalt in a reaction system, carrying out a heteroatomization reaction in the reaction system to form an asphalt melt, carrying out distillation cutting on the asphalt melt to separate out unreacted components, and carrying out vacuum drying to obtain the heteroatom-containing high-softening-point asphalt. The high-softening-point asphalt containing the heteroatoms is obtained. The system comprises a feeding system used for conveying materials to a spiral reactor; the spiral reactor is used for providing a reaction place for asphalt heating melting and heteroatomization reaction; the short-path distillation device is used for distilling, cutting and separating the asphalt melt obtained by the spiral reactor; the high-softening-point asphalt tank is used for collecting high-softening-point asphalt obtained by distillation and cutting of the short-path distillation device; and the light component asphalt tank is used for collecting light components obtained by distillation and cutting of the short-path distillation device. According to the continuous production method provided by the invention, the composition of a production system is simplified while the uniformity of the prepared heteroatom-containing high-softening-point asphalt is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon material preparation, and in particular to a high softening point asphalt containing heteroatoms with simple process, low energy consumption and continuous production, and a preparation method and system thereof. Background Art

[0002] High softening point asphalt is also called high carbon resin asphalt material. Its softening point is usually above 200℃. It has excellent high temperature resistance and has been widely used. It can be used as an important engineering material. It can play the role of plugging, anti-collapse, coating and bonding under high temperature conditions, such as in deep oil and gas field drilling fluid and building waterproofing; it can also be used as a modified additive for polymer materials, such as waterproof roll preparation. In addition, it can also be used as a raw material for new carbon materials, such as asphalt-based carbon fiber, needle coke, foam carbon, high-end activated carbon, etc., which are used to prepare lithium battery negative electrode materials. The market demand is very large. In some special fields, high softening point asphalt containing heteroatoms is needed, such as coated asphalt, hard carbon, high-end activated carbon and other carbon materials. High softening point asphalt containing heteroatoms such as O, N, S, I is needed to improve the adsorption and wetting properties of carbon materials. The market demand for this type of high softening point asphalt is steadily increasing.

[0003] At present, the production of high softening point asphalt containing heteroatoms is mainly achieved by intermittent kettle reaction process.

[0004] Chinese patent CN 102464989B heats the asphalt raw material to a molten state, mixes it with 0.01%-5% of the reactant additive and air for pre-reaction, and then performs high-speed blowing oxidation to obtain oxygen-containing high-softening point asphalt. Chinese patent CN102504853B uses oxygen in the air as an oxidant to modify the purified asphalt without QI at a temperature of 150℃ to 350℃ through a three-stage kettle oxidation process, and then filters and cools it to obtain asphalt with a softening point of 220℃ to 295℃; Chinese patent CN 105567275B adds low-QI high-purity impregnating agent asphalt to a stirred reactor, and introduces air and nitrogen, and performs air oxidation at 180~330℃ for 10~30h. The obtained product is put into a scraped film evaporator for film distillation to remove light components, and obtains high-purity oxygen-containing high-softening point asphalt with a softening point of 250℃ to 300℃; Chinese patent CN 103361096B The refined soft asphalt raw material is subjected to reduced pressure distillation to remove low-boiling point components, and then the softening point is adjusted to 250°C to 280°C through oxidation and vacuum film distillation to obtain oxygen-containing high-softening point spinnable asphalt.

[0005] Chinese patent CN101259961A discloses a method for preparing nitrogen-containing high-softening point asphalt, which comprises placing raw material asphalt, naphthalene and nitrogen-containing compounds in a high-pressure reactor in a certain proportion, heating and polymerizing, preparing nitrogen-containing high-softening point asphalt, and using the raw material as the raw material through infusibility, carbonization and activation to prepare nitrogen-containing spherical activated carbon; Chinese patent CN 105413636A discloses a method for preparing high-sulfur content asphalt and activated carbon, which comprises placing elemental sulfur and heavy aromatic compounds in a reactor in a certain proportion, heating and polymerizing, preparing sulfur-containing asphalt, and then preparing high-sulfur content activated carbon through oxidation, carbonization and activation.

[0006] In summary, the preparation process of high-softening-point asphalt containing heteroatoms in the prior art mainly relies on intermittent autoclave reactions, which have too long reaction times and complex processes. At the same time, there are problems such as low oxidation / nitridation / sulfurization efficiency and uneven product asphalt components. In addition, the reactor is prone to uneven heating, and common problems such as intermediate phases and low product yields are likely to occur during high-temperature thermal polycondensation. In response to these problems, multi-stage reaction devices are often used in industrial production processes, which increase process complexity, high energy consumption, and are more prone to coking, resulting in difficulties in discharging and post-processing. Therefore, there is still a need to develop methods that can controllably, continuously and efficiently produce high-softening-point asphalt containing heteroatoms with a reasonable molecular weight distribution. Summary of the invention

[0007] In view of the problems existing in the above-mentioned prior art, an object of the present invention is to provide a high softening point asphalt containing heteroatoms and a low-cost, simple-process continuous production method and system thereof, so as to improve the uniformity of the preparation of high softening point asphalt containing heteroatoms while simplifying the system composition of producing high softening point asphalt.

[0008] In order to achieve the purpose of the present invention, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a method for continuously preparing a high-softening-point asphalt containing heteroatoms. The asphalt is heated and melted in a polymerization reaction system, and a heteroatomization reaction is carried out in the polymerization reaction system to form an asphalt melt. The asphalt melt is distilled and cut to separate unreacted light components, thereby obtaining a high-softening-point asphalt containing heteroatoms.

[0010] In some specific embodiments, the softening point of the asphalt is 80° C. to 200° C. In some preferred embodiments, the asphalt is selected from coal liquefaction asphalt, coal tar pitch, petroleum asphalt or impregnated asphalt.

[0011] In some specific embodiments, the heating and melting is carried out at 250°C to 400°C, and the asphalt is crushed to a particle size of 1 to 10 mm and then heated and melted, preferably 1 to 5 mm, for example, 2 mm, 3 mm, 4 mm.

[0012] In some specific embodiments, a heteroatom-containing gas or a heteroatom-containing solid material is introduced into the polymerization reaction to carry out a heteroatomization reaction; the heteroatomization reaction is carried out at 10-80 KPa and 280° C.-400° C. for 2-10 min. In some preferred embodiments, the heteroatom-containing gas is introduced into the reaction at a ventilation rate of 100-800 L / min.

[0013] In some specific embodiments, the heteroatom-containing gas is selected from one or more of nitrogen, ammonia or oxygen, or air; the heteroatom-containing solid material is selected from one or more of melamine, melamine formaldehyde resin, sulfur powder or elemental iodine. In some preferred embodiments, the particle size of the heteroatom-containing solid material is 1 to 5 mm, for example, 2 mm, 3 mm, 4 mm.

[0014] In a second aspect, the present invention provides a production system using the above-mentioned continuous preparation method, comprising:

[0015] A feeding system for conveying asphalt and materials containing heteroatoms to the spiral reactor;

[0016] A spiral reactor is used to provide a reaction site for asphalt heating, melting and heteroatomization reactions. The spiral reactor includes a transmission and stirring assembly, an inner cavity that can accommodate the transmission and stirring assembly, and a heavy oil tank. The heavy oil tank is connected to the upper part of the inner cavity. The feed port of the inner cavity is connected to the discharge port of the feeding system. The discharge port of the inner cavity is connected to a short-range distillation device.

[0017] A short-path distillation device is used to distill and cut the asphalt melt obtained from the spiral reactor, and the discharge port of the short-path distillation device is connected to the high softening point asphalt tank and the light component asphalt tank respectively;

[0018] A high softening point asphalt tank, used to collect the high softening point asphalt obtained by distillation and cutting of the short-path distillation device;

[0019] The light component asphalt tank is used to collect the light components obtained by distillation and cutting of the short-path distillation device.

[0020] In the production system provided by the present invention, the spiral reactor has multiple functions such as transmission stirring, uniform mixing of reaction materials, heteroatomization reaction, and removal of volatiles. All reaction steps in the spiral reactor can be completed in one step and a product asphalt melt with certain fluidity is formed.

[0021] In the production system provided by the present invention, the short-range distillation device can be a short-range distillation device conventionally used in the industry, or a modified short-range distillation device with a special structure; in order to ensure the separation efficiency, preferably, a scraping film evaporation method is selected, wherein the distance between the scraper and the inner wall of the device is 1 to 4 mm; in order to adapt to different asphalt components, preferably, the scraper drive motor of the short-range distillation device is an adjustable frequency motor. In some specific embodiments, a feed pump is provided between the asphalt buffer tank and the short-range distillation device to pump the product asphalt in the asphalt buffer tank into the short-range distillation device. Preferably, the feed pump can be a gear pump, and preferably, a heat-insulating jacket is also provided at the pump head of the feed pump.

[0022] In some specific embodiments, a thermal insulation jacket is provided on the periphery of the short-range distillation device, and the heating medium can be high-temperature heat transfer oil or molten salt, which can be reasonably selected according to actual needs; for example, the distillation process temperature of the short-range distillation device is 300°C to 400°C, the vacuum degree is 1 to 2000Pa, and the driving motor frequency is 5 to 100Hz.

[0023] In some specific embodiments, the production system further includes an asphalt buffer tank, the feed port of the asphalt buffer tank is connected to the discharge port of the inner cavity, and the discharge port of the asphalt buffer tank is connected to the feed port of the short-range distillation device; a condenser I is provided on the pipeline between the heavy oil tank and the inner cavity, which is used to condense the heavy oil components removed from the asphalt in the inner cavity; a condenser II is provided on the pipeline between the short-range distillation device and the light component asphalt tank, which is used to condense the gas phase components obtained by distillation and cutting in the short-range distillation device. Specifically, after the raw asphalt undergoes heteroatomization reaction and heavy oil removal process in the spiral reactor, it enters the asphalt buffer tank through the connected pipeline, and the removed heavy oil component enters the heavy oil tank after being cooled by condenser I. After being processed by the short-range distillation device, the high softening point asphalt enters the high softening point asphalt tank by gravity, while the light component enters the condenser II, and after condensation, it enters the light component asphalt tank by gravity.

[0024] In some specific embodiments, the temperature of the light component asphalt tank is controlled at 200℃~350℃, for example, 250℃, 300℃, 320℃; the temperature of the high softening point asphalt tank is controlled at 250℃~380℃, for example, 280℃, 300℃, 350℃.

[0025] In some specific embodiments, the inner cavity of the spiral reactor has a channel connected to the condenser I and the vacuum device. In order to control the internal vacuum degree and product effect, preferably, the number of vacuum interfaces on the spiral reactor is 2 to 10, for example, 3, 5, or 8.

[0026] In some specific embodiments, the feeding system includes an asphalt tank and a compressed gas tank; wherein the discharge port of the asphalt tank is connected to the feed port of the inner cavity to provide asphalt raw materials for the spiral reactor; in order to facilitate the counting of the feed amount during production, preferably, the asphalt tank is equipped with an electronic scale. In some preferred embodiments, a spiral feeder is also provided between the discharge port of the asphalt tank and the feed port of the inner cavity to transport the asphalt in the asphalt tank to the spiral reactor.

[0027] The transmission stirring assembly includes a transmission shaft and a spiral impeller fixed on the rotating shaft, a gas feed port is provided on the spiral impeller, and the compressed gas tank is connected to the gas feed port on the spiral impeller, so as to provide the spiral reactor with heteroatom-containing gas. As is well known in the art, the transmission shaft is fixedly connected to the spiral impeller, and the transmission shaft is driven to rotate by a motor so that the spiral impeller also rotates, thereby achieving mixing disturbance of the asphalt and the heteroatom-containing material in the inner cavity.

[0028] In some preferred embodiments, the aperture of the gas feed port is 3 to 8 mm, and further, the distribution density of the gas feed port is 1 to 3 per cm 2 When it is necessary to transport heteroatom-containing gas to the spiral reactor, the compressed gas tank transports the heteroatom-containing gas to the inner cavity of the spiral reactor through the gas feed port on the spiral impeller. When it is necessary to transport solid materials containing heteroatoms to the spiral reactor, the solid materials can be placed in an asphalt tank and mixed with asphalt before being transported to the spiral reactor.

[0029] In some specific embodiments, in order to optimize the preheating effect of the raw materials in the spiral reactor, the length-to-diameter ratio of the inner cavity is (30-65):1, for example, 35:1, 40:1, 45:1, 50:1, 55:1, 60:1.

[0030] In some specific embodiments, the asphalt buffer tank is a storage tank commonly used in the industry. In order to control the temperature in the asphalt buffer tank, preferably, the periphery of the asphalt buffer tank is provided with an insulation jacket. The setting of the insulation jacket can be carried out by conventional process means in the art, wherein there are no special requirements for the selection of the heating medium and the selection of the heating system (used to heat the heating medium), which can be reasonably selected according to the temperature requirements of the asphalt buffer tank. A mechanical stirring mechanism is provided inside the asphalt buffer tank to achieve uniform heating of the asphalt in the tank and uniform distribution of the asphalt components. For example, the temperature of the asphalt buffer tank is controlled at 250°C to 350°C, such as 280°C, 300°C, and 320°C; the stirring rate can be 5 to 100rpm / min, such as 20rpm / min, 50rpm / min, and 80rpm / min. In some specific embodiments, the high softening point asphalt tank, the light component asphalt tank, and the short-range distillation device are all provided with a heating system.

[0031] In some preferred embodiments, the heating system can be selected from an insulation jacket. Specifically, the heating medium in the insulation jacket of the high softening point asphalt tank and the short-path distillation unit is the same; the heating medium in the insulation jacket of the light component asphalt tank and the asphalt buffer tank is the same.

[0032] In some specific embodiments, the high softening point asphalt tank and the light component asphalt tank are connected to a granulation device for granulation, packaging and storage.

[0033] In a third aspect, the present invention provides a high softening point asphalt containing heteroatoms, wherein the high softening point asphalt is prepared according to the above-mentioned continuous preparation method or using the above-mentioned production system, and the softening point of the high softening point asphalt is 240°C to 270°C, for example, 245°C, 250°C, 255°C, 260°C, 265°C.

[0034] The above technical solution has the following technical effects:

[0035] The preparation method provided by the present invention can complete the preparation of high-softening-point asphalt containing heteroatoms in one step. The polymerization reaction system is used to heat the asphalt raw material to a predetermined temperature for melting, and after reacting with the material containing heteroatoms, it enters into a short-range distillation cutting to separate different components. This can effectively simplify the continuous production device of high-softening-point asphalt containing heteroatoms, reduce equipment costs, improve production efficiency, and be pollution-free to the environment. At the same time, it also avoids the problems of intermediate phases and coking in the product caused by uneven heating due to the complex process in the intermittent production method.

[0036] The high softening point asphalt containing heteroatoms provided by the present invention has isotropy and good uniformity, and the softening point can be controlled at 240°C to 270°C. It can be used as a raw material for high-end carbon materials such as coated asphalt, asphalt-based carbon fiber, needle coke, foamed carbon, high-end activated carbon, and hard carbon. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 : A specific implementation of the heteroatom-containing high softening point asphalt production system provided by the present invention;

[0038] Figure 2 : A specific structural schematic diagram of a spiral reactor in a production system provided by the present invention;

[0039] Figure 3 : Polarized image of the high softening point asphalt containing heteroatoms obtained in Example 1;

[0040] Figure 4 : Polarized image of the high softening point asphalt containing heteroatoms obtained in Example 2;

[0041] Figure 5 : Polarized image of the high softening point asphalt containing heteroatoms obtained in Example 3;

[0042] Among them, 1. Asphalt storage tank, 2. Screw loader, 3. Screw reactor, 31. Drive shaft, 32. Screw impeller, 33. Inner cavity, 34. Gas feed port, 4. Condenser I, 5. Heavy oil tank, 6. Asphalt buffer tank, 7. Compressed gas tank, 8. Short-range distillation unit, 9. High softening point asphalt tank, 10. Condenser II, 11. Light component asphalt tank. DETAILED DESCRIPTION

[0043] In order to facilitate the understanding of the present invention, the present invention will be further described below in conjunction with examples. It should be understood that the following examples are only for a better understanding of the present invention and do not mean that the present invention is limited to the following examples.

[0044] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0045] The asphalt raw materials used in the following embodiments of the present invention are:

[0046] (1) Coal liquefaction pitch produced by Shenhua Coal-to-Liquid Chemical Company Ordos Coal-to-Liquid Branch in the coal liquefaction oil residue extraction process: the softening point of the pitch is 162°C, the coking value is 61%, the ash content is 0.1%, and the softening point deviation is ±3°C;

[0047] (2) Petroleum-based modified asphalt: The softening point of this asphalt is 116°C, the coking value is 55%, the ash content is 0.4%, and the softening point deviation is ±5°C.

[0048] like Figure 1 As shown, the production system provided by the present invention comprises:

[0049] A feeding system, used for conveying asphalt and materials containing heteroatoms to the spiral reactor 3;

[0050] The spiral reactor 3 is used to provide a reaction site for asphalt heating, melting and heteroatomization reaction. The spiral reactor 3 includes a transmission stirring assembly, an inner cavity 33 that can accommodate the stirring assembly and a heavy oil tank 5. The heavy oil tank 5 is connected to the upper part of the inner cavity. The feed port of the inner cavity is connected to the inlet of the feeding system, and the discharge port of the inner cavity is connected to the short-range distillation device 8.

[0051] The asphalt buffer tank 6 is connected to the discharge port of the inner cavity 33 of the spiral reactor 3, and the discharge port is connected to the feed port of the short-path distillation device 8;

[0052] A short-path distillation device 8 is used to distill and cut the asphalt melt obtained from the spiral reactor 3, and the discharge port of the short-path distillation device 8 is connected to a high softening point asphalt tank 9 and a light component asphalt tank 11 respectively;

[0053] The high softening point asphalt tank 9 is used to collect the high softening point asphalt obtained by distillation and cutting of the short-path distillation device 8;

[0054] The light component asphalt tank 11 is used to collect the light components obtained by distillation and cutting in the short-path distillation device 8.

[0055] A condenser I4 is provided on the pipeline between the heavy oil tank 5 and the inner cavity, which is used to condense the heavy oil component removed from the asphalt in the inner cavity; a condenser II10 is provided on the pipeline between the short-path distillation device 8 and the light component asphalt tank 11 to condense the gas phase component obtained by distillation and cutting in the short-path distillation device 8.

[0056] In the production system, the feeding system includes an asphalt tank 1 and a compressed gas tank 7; wherein the discharge port of the asphalt tank 1 is connected to the feed port of the inner cavity to provide the raw material of asphalt to the spiral reactor 3; a spiral feeder 2 is also provided between the discharge port of the asphalt tank 1 and the feed port of the inner cavity;

[0057] like Figure 2 As shown, the transmission stirring assembly in the specific spiral reactor 3 includes a spiral impeller 32 and a transmission shaft 31 that drives the spiral impeller 32 to rotate. A gas feed port 34 is opened on the surface of the spiral impeller 32. The gas feed port 34 is connected to the compressed gas tank 7 to provide the spiral reactor 3 with heteroatom-containing gas.

[0058] Example 1

[0059] Using the above production system, the coal liquefied asphalt with a particle size of ≤5mm after crushing and screening is placed in the asphalt tank 1, enters the screw feeder 2 through the channel at the bottom of the asphalt tank 1, and is transported to the spiral reactor 3. At the same time, a mixed gas of ammonia and nitrogen (mixed volume ratio of 1:1, ventilation volume of 300L / min) is introduced into the spiral impeller 32 of the spiral reactor 3 through the compressed gas tank 7. Specifically, the aperture of the gas feed port 34 on the surface of the spiral impeller 32 is 4mm, and the distribution density is 1 / cm 2 ; Under the conditions of temperature of 320°C and vacuum degree of 80 kPa, the asphalt stays in the spiral reactor 3 for 8 minutes to be heated and melted and undergo nitridation polymerization reaction to form asphalt melt;

[0060] The asphalt melt enters the asphalt buffer tank 6, the temperature of which is 300°C, and the agitator rotates at a speed of 150rpm / min. Then the product asphalt enters the scraped film evaporation short-range distillation device 8 through the feed pump, the distance between the scraper and the inner wall of the device is 2mm, the temperature is 380°C, the vacuum degree is 1500Pa, and the drive motor frequency is 40Hz. After distillation separation, the light component enters the multi-stage condenser 10 and is cooled and then enters the light component asphalt tank 11, and then is sent to different cooling and molding devices for molding; the heavy component with a high softening point enters the high softening point asphalt tank 9 by gravity, and then is also sent to the cooling and molding device for molding to obtain nitrogen-containing high softening point asphalt.

[0061] According to the test, the nitrogen content in the nitrogen-containing high softening point asphalt is 4wt%, the softening point is 244℃, and the coking value is 68%.

[0062] Example 2

[0063] Using the above production system, the petroleum-based modified asphalt with a particle size of ≤5 mm after crushing and screening is placed in the asphalt tank 1, enters the screw feeder 2 through the channel at the bottom of the asphalt tank 1, and is transported to the spiral reactor 3. At the same time, a mixed gas of oxygen and nitrogen (mixed volume ratio of 1:1, ventilation volume of 200L / min) is introduced into the spiral impeller 32 of the spiral reactor 3 through the compressed gas tank 7. Specifically, the aperture of the gas feed port 34 on the surface of the spiral impeller 32 is 4mm, and the distribution density is 1 / cm 2 ; Under the conditions of temperature of 350°C and vacuum degree of 80 kPa, the asphalt stays in the spiral reactor 3 for 5 minutes to be heated and melted and undergo oxidative polymerization reaction to form asphalt melt;

[0064] The asphalt melt enters the asphalt buffer tank 6, the temperature of which is 300°C, and the agitator rotates at a speed of 130rpm / min. Then the product asphalt enters the scraped film evaporation short-range distillation device 8 through the feed pump, the distance between the scraper and the inner wall of the device is 1mm, the temperature is 380°C, the vacuum degree is 200Pa, and the drive motor frequency is 200Hz. After distillation separation, the light component enters the multi-stage condenser 10 and is cooled and then enters the light component asphalt tank 11, and then is sent to different cooling and molding devices for molding; the heavy component with a high softening point enters the high softening point asphalt tank 9 by gravity, and then is also sent to the cooling and molding device for molding to obtain oxygen-containing high softening point asphalt.

[0065] After testing, the oxygen content of the oxygen-containing high softening point asphalt is 5wt%, the softening point is 255℃, and the coking value is 76.2%.

[0066] Example 3

[0067] Using the above production system, coal liquefaction asphalt with a particle size of ≤5 mm after crushing and screening and elemental sulfur powder are placed in an asphalt tank 1 at a mass ratio of 10:1, and then enter the screw feeder 2 through the channel at the bottom of the asphalt tank 1 and are transported to the screw reactor 3; at the same time, nitrogen is introduced into the spiral impeller 32 of the spiral reactor 3 (the ventilation volume is 100L / min). Specifically, the aperture of the gas feed port 34 on the surface of the spiral impeller 32 is 4mm, and the distribution density is 1 / cm 2 ; Under the conditions of temperature of 320°C and vacuum degree of 60 kPa, the asphalt stays in the spiral reactor 3 for 8 minutes to be heated and melted and undergo a sulfide polymerization reaction to form an asphalt melt;

[0068] The asphalt melt enters the asphalt buffer tank 6, the temperature of which is 300°C, and the agitator rotates at a speed of 150rpm / min. Then the product asphalt enters the scraped film evaporation short-range distillation device 8 through the feed pump, the distance between the scraper and the inner wall of the device is 2mm, the temperature is 380°C, the vacuum degree is 1000Pa, and the drive motor frequency is 30Hz. After distillation and separation, the light component enters the multi-stage condenser 10 and is cooled and then enters the light component asphalt tank 11, and then is sent to different cooling and molding devices for molding; the heavy component with a high softening point enters the high softening point asphalt tank 9 by gravity, and then is also sent to the cooling and molding device for molding to obtain nitrogen-containing high softening point asphalt.

[0069] According to the test, the sulfur-containing high softening point asphalt has a nitrogen content of 7wt%, a softening point of 264°C, and a coking value of 80%.

[0070] Example 4

[0071] The same production system as in Example 1 is used to prepare nitrogen-containing high softening point asphalt, the difference in the method being that the flow rate of the mixed gas introduced from the compressed gas tank 7 into the spiral impeller 32 of the spiral reactor 3 is 500 L / min.

[0072] According to the test, the nitrogen content in the nitrogen-containing high softening point asphalt is 5.6wt%, the softening point is 253℃, and the coking value is 75%.

[0073] Example 5

[0074] The same production system as in Example 1 is used to prepare nitrogen-containing high softening point asphalt, the difference in the method being that the temperature of the nitridation polymerization reaction in the spiral reactor 3 is 350°C.

[0075] According to the test, the nitrogen content in the nitrogen-containing high softening point asphalt is 5.2wt%, the softening point is 254°C, and the coking value is 76.4%.

[0076] Example 6

[0077] The same production system as in Example 1 is used to prepare nitrogen-containing high softening point asphalt, the difference in the method being that the asphalt stays in the spiral reactor 3 for 10 minutes for heating, melting and nitridation polymerization reaction.

[0078] According to the test, the nitrogen content in the nitrogen-containing high softening point asphalt is 4.3wt%, the softening point is 248°C, and the coking value is 73%.

[0079] Example 7

[0080] The same production system as in Example 2 is used to prepare nitrogen-containing high softening point asphalt, the difference in the method being that the air flow rate of the mixed gas introduced from the compressed gas tank 7 into the spiral impeller 32 of the spiral reactor 3 is 400 L / min.

[0081] According to the test, the nitrogen content in the oxygen-containing high softening point asphalt is 7wt%, the softening point is 265℃, and the coking value is 81%.

[0082] Example 8

[0083] The same production system as in Example 3 is used to prepare nitrogen-containing high softening point asphalt, the difference in the method being that the elemental sulfur powder is replaced by a nitrogen-containing material - melamine.

[0084] According to the test, the nitrogen content of the nitrogen-containing high softening point asphalt is 6wt%, the softening point is 268°C, and the coking value is 77%.

[0085] From the attached Figure 3-5 It can be seen from the polarized light image that the high softening point asphalt containing heteroatoms prepared by the method of the present invention is isotropic and has high uniformity.

Claims

1. A continuous preparation method of high softening point asphalt containing heteroatoms, characterized in that: The asphalt is heated and melted in a reaction system, and then a heteroatomization reaction is carried out in the reaction system to form an asphalt melt. The asphalt melt is distilled and cut to separate unreacted light components, thereby obtaining a high softening point asphalt containing heteroatoms.

2. The continuous preparation method according to claim 1, characterized in that: The softening point of the asphalt is 80-200°C; Preferably, the asphalt is selected from coal liquefaction asphalt, coal tar, petroleum asphalt or impregnated asphalt.

3. The continuous preparation method according to claim 2, characterized in that: The heating and melting is carried out at 250-400°C and 10-80kPa; Preferably, the asphalt is crushed to a particle size of 1 to 10 mm, preferably 1 to 5 mm, and then heated and melted.

4. The continuous preparation method according to claim 3, characterized in that: The heteroatomization reaction is carried out at 10-80 kPa and 280-400° C. for 2-10 minutes; Preferably, a gas containing heteroatoms or a solid material containing heteroatoms is introduced into the reaction to carry out a heteroatomization reaction; More preferably, the flow rate of the heteroatom-containing gas introduced into the reaction is 100 to 800 L / min.

5. The continuous preparation method according to claim 4, characterized in that: The heteroatom-containing gas is selected from one or more of nitrogen, ammonia or oxygen; The solid material containing heteroatoms is selected from one or more of melamine, melamine formaldehyde resin, sulfur powder or elemental iodine; Preferably, the particle size of the solid material containing heteroatoms is 1 to 5 mm.

6. A production system using the continuous preparation method according to any one of claims 1 to 5, characterized in that: include: A feeding system for conveying asphalt and materials containing heteroatoms to the spiral reactor; A spiral reactor is used to provide a reaction site for asphalt heating, melting and heteroatomization reactions. The spiral reactor includes a transmission and stirring assembly, an inner cavity that can accommodate the transmission and stirring assembly, and a heavy oil tank. The heavy oil tank is connected to the upper part of the inner cavity. The feed port of the inner cavity is connected to the discharge port of the feeding system. The discharge port of the inner cavity is connected to a short-range distillation device. A short-path distillation device is used to distill and cut the asphalt melt obtained from the spiral reactor, and the discharge port of the short-path distillation device is connected to the high softening point asphalt tank and the light component asphalt tank respectively; A high softening point asphalt tank, used to collect the high softening point asphalt obtained by distillation and cutting of the short-path distillation device; The light component asphalt tank is used to collect the light components obtained by distillation and cutting of the short-path distillation device.

7. The production system according to claim 6, characterized in that: The feeding system includes an asphalt tank and a compressed gas tank; The discharge port of the asphalt tank is connected to the feed port of the inner cavity to provide asphalt to the spiral reactor; preferably, a spiral feeder is also provided between the discharge port of the asphalt tank and the feed port of the inner cavity; The transmission stirring assembly includes a transmission shaft and a spiral impeller fixed on the transmission shaft. The spiral impeller is provided with a gas feed port. The compressed gas tank is connected to the gas feed port on the spiral impeller to provide the spiral reactor with a gas containing heteroatoms.

8. The production system according to claim 6 or 7, characterized in that: The production system further comprises an asphalt buffer tank, wherein the feed port of the asphalt buffer tank is connected to the discharge port of the inner cavity, and the discharge port of the asphalt buffer tank is connected to the feed port of the short-range distillation device; A condenser I is provided on the pipeline between the heavy oil tank and the inner cavity, for condensing the heavy oil components removed from the asphalt in the inner cavity; A condenser II is provided on the pipeline between the short-path distillation device and the light component asphalt tank, and is used to condense the gas phase components obtained by distillation cutting in the short-path distillation device.

9. The production system according to any one of claims 6 to 8, characterized in that: The high softening point asphalt tank, light component asphalt tank, asphalt buffer tank and short-range distillation device are all provided with a heating system.

10. A high softening point asphalt containing heteroatoms, characterized in that: The high softening point asphalt is prepared by the continuous preparation method according to any one of claims 1 to 5 or by the production system according to any one of claims 6 to 9; The high softening point asphalt has a softening point of 240-270°C.

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