An ethylene tar polymerization reaction device and process

Abstract

The present invention relates to the technical field of deep processing of petrochemical by-products, and discloses a reactor, an ethylene tar polymerization reaction device, and a process. The reactor includes alternating double-spiral impellers and coil-type heat exchangers to achieve temperature uniformity, and a perforated plate is provided to reduce material back-mixing. The ethylene tar polymerization reaction device includes the aforementioned reactor and a separation tank. The ethylene tar polymerization reaction process includes the following steps: S2. Continuously performing a multi-stage catalytic polymerization reaction; S3. Multi-stage separation to obtain a liquid-phase ethylene tar catalytic polymerization product. The reactor and ethylene tar polymerization reaction device disclosed in the present invention can improve the uniformity of the ethylene tar catalytic reaction, including material uniformity, temperature uniformity, and prevention of material back-mixing. The ethylene tar polymerization reaction process, based on the use of a multi-stage polymerization reaction, further improves the uniformity of the reaction process, thereby increasing the coking value and yield.

Description

Technical Field

[0001] The present invention relates to the technical field of deep processing of petrochemical by-products, in particular to an ethylene tar polymerization reaction device and process. Background Art

[0002] Ethylene tar is a product of the high-temperature condensation of cracking feedstock during steam cracking. China has an annual production capacity of approximately 4 million tons. This heavy oil byproduct features high density, a high carbon-to-hydrogen atomic ratio, and a high aromatics content. It is a high-quality raw material for the production of high-quality, high-value new carbon materials. It is crucial for the differentiated utilization of coal chemical and petrochemical products, extending the industrial chain. However, currently, most of it is directly burned as fuel, causing serious environmental pollution and resource waste.

[0003] High softening point coated asphalt, as a new type of carbon material, can be used as a negative electrode coating material for lithium batteries to improve the first charge reversible capacity, cycle stability and battery rate performance of the negative electrode material. It can be prepared from ethylene tar.

[0004] Among existing processes for producing coated asphalt using inferior heavy oils, Chinese patent CN201110282026.6 discloses a process for producing high-softening-point, isotropic asphalt by introducing air into a tubular oxidation furnace for oxidation, followed by thermal polycondensation in a reactor. This patent and current industry data indicate that the current production of high-softening-point asphalt from heavy oils such as ethylene tar faces the following major challenges:

[0005] The existing process is generally an oxidative polymerization process with a single-pot intermittent operation. The cold material needs to be heated and the hot material needs to be cooled. The reaction temperature cannot be accurately controlled, and the process consumes a lot of energy. The auxiliary time for heating and cooling is long, and energy is not reasonably utilized. There is material backmixing in the reaction, and the molecular weight distribution of the resin asphalt is uneven. This leads to defects such as the inability to guarantee product quality and low production capacity.

[0006] Based on the above, the present application provides an ethylene tar polymerization reaction device and process to solve the existing defects. Summary of the Invention

[0007] The object of the present invention is to provide an ethylene tar polymerization reaction device and process to solve the problems raised in the above background technology.

[0008] The existing process of producing high softening point asphalt by polymerization reaction of ethylene tar has the problems of single-kettle intermittent operation, low production efficiency, low production capacity, unstable product quality and high production energy consumption.

[0009] In order to solve this problem, Chinese patent CN115948176A discloses a process for producing high softening point asphalt through a continuous reaction of multiple reactors in series. It proposes to achieve the continuity of the reaction through a multi-stage polymerization reaction, avoid the energy loss caused by intermittent temperature increase and decrease, and remove the light components that do not participate in the reaction from the system in time while the polymerization reaction is in progress, so as to strengthen the reaction process, improve the reaction efficiency, and thus solve the defects of the single-reactor intermittent operation in the traditional process.

[0010] The present invention proposes another idea, which is to focus on improving the uniformity of the reaction process on the basis of multi-stage polymerization reaction (mainly reflected in the mixing degree of materials in each stage and the precise control of temperature in each reaction stage), so as to strengthen the reaction process and improve the reaction efficiency. It is also used to solve the problems of low production capacity, unstable quality and high energy consumption in traditional processes.

[0011] Based on this idea, the present invention first proposes the following technical solution: a reaction kettle.

[0012] In general shell-and-tube heat exchangers, materials often cannot pass through the tubes evenly, resulting in difficulty in achieving uniform heating of the materials. The ethylene tar polymerization reaction progress in each area is inconsistent, and there is a problem of material mixing. This causes ethylene tar with inconsistent polymerization reaction progress to enter other areas for reaction, occupying the energy of other areas, resulting in low energy utilization and unstable product quality.

[0013] Based on this, this reactor proposes to achieve temperature uniformity by alternately setting up double-spiral impellers and coil heat exchangers, and at the same time setting up orifice plates to reduce the phenomenon of material mixing, thereby improving energy utilization, providing stable and controllable reaction conditions, and achieving an increase in coking value and yield.

[0014] Preferably, the reactor includes a main body, on which a material inlet and a material outlet are provided, so that the material moves from bottom to top. The main body is the outer shell of a traditional reactor; it also includes stirring elements and coil-tube heat exchangers alternately arranged in the extension direction of the main body, and a heat medium inlet and a heat medium outlet corresponding to each coil-tube heat exchanger, wherein the stirring element is used to stir the material to make the fluid concentration and temperature of each area in the reactor more uniform, and the coil-tube heat exchanger makes the flow state of the heat medium closer to the plug flow, avoiding large temperature differences of the materials in the area. The alternating stirring elements and coil-tube heat exchangers make it easier to control the temperature in sections and better ensure the uniformity of the temperature of the reaction materials; it also includes a orifice plate arranged between two coil-tube heat exchangers, which ensures the circulation of the material and can, to a certain extent, prevent the axial back mixing of the material, thereby achieving uniformity of the reaction process.

[0015] Further preferably, the stirring element is specifically as follows: each stirring element includes two double-spiral impellers, the two double-spiral impellers of each stirring element face opposite directions, each orifice plate corresponds to each stirring element one by one, and the orifice plate is placed between the two impellers of the stirring element.

[0016] Based on this idea, the present invention also proposes the following technical solution: an ethylene tar polymerization reaction device.

[0017] Specifically, the reaction device is designed with the above-mentioned reactor as the center, so that the reaction device is suitable for the ethylene tar polymerization process.

[0018] Preferably, the reaction device includes a stirring tank, which is used to mix the material and the catalyst; it also includes the above-mentioned multi-stage reactor, the output end of the stirring tank is connected to the material inlet of the first-stage reactor, and the multi-stage reactors are connected in series so that the material reacts continuously in the multi-stage reactor; it also includes a multi-stage separation tank, each stage of the separation tank includes a separation feed port, a light component discharge port and a heavy component discharge port, the material outlet of the last stage of the reactor is connected to the separation feed port of the first-stage separation tank, and the heavy component discharge port of each stage of the separation tank is connected to the separation feed port of the next stage of the separation tank. The multi-stage separation tank finally obtains a liquid phase ethylene tar catalytic polymerization product, and the polymerization product is then sent to a subsequent deep pressure reduction separation section to finally obtain a high softening point coated asphalt.

[0019] Based on this idea, the present invention also proposes the following technical solution: an ethylene tar polymerization reaction process, which is carried out in the aforementioned reaction device, combined with precise control of the temperature, pressure, etc. of the multi-stage catalytic polymerization reaction, and ultimately used to obtain a high-softening-point coated asphalt with high coking value and high yield.

[0020] Specifically, this reaction process includes the steps of:

[0021] S1. Stirring the ethylene tar heavy component and the catalyst;

[0022] S2. Continuously carry out multi-stage catalytic polymerization reaction;

[0023] S3. Multi-stage separation to obtain a liquid phase ethylene tar catalytic polymerization product;

[0024] S4. The high softening point coated asphalt is obtained by vacuum separation treatment.

[0025] Preferably, the ethylene tar heavy component is obtained by purifying and distilling industrial naphthalene-free ethylene tar, and the Ennsley initial boiling point (IBP) of the naphthalene-free ethylene tar is ≥170°C and the Ennsley final boiling point (FBP) is ≤680°C.

[0026] Further preferably, in step S2, the pressure of the multi-stage catalytic polymerization reaction is 0.5-3 MPa, the total time is 5-10 hours, and the temperature is 180° C.-410° C., which includes the steps of:

[0027] S2a. A primary catalytic polymerization reaction at a temperature of 180°C to 300°C, wherein the medium in the reactor is thermal oil;

[0028] S2b. Secondary catalytic polymerization reaction, the reaction temperature is 300 ℃ ~ 360 ℃, the medium in the reactor is molten salt;

[0029] S2c. Three-stage catalytic polymerization reaction, the reaction temperature is 360℃~410℃, and the medium in the reactor is molten salt.

[0030] More preferably, before the continuous multi-stage catalytic polymerization reaction in step S2, the method further comprises step S1 of performing a preheating treatment: preheating the ethylene tar heavy component to a temperature of 160°C to 200°C.

[0031] Further preferably, the catalyst in step S1 is composed of an organic solvent mixture consisting of alkylbenzene sulfonic acid, unsaturated fatty acid, petroleum cyclopentane acid compound and other polar non-hydrocarbon compounds, and the content of each compound in the catalyst is between 10% and 50%; wherein the alkylbenzene sulfonic acid compound is one or more of undecylbenzenesulfonic acid, linear dodecylbenzenesulfonic acid, branched dodecylbenzenesulfonic acid, and tetracosyl-benzenesulfonic acid, the unsaturated fatty acid is one or more of C14 to C24 unsaturated fatty acids, the petroleum cyclopentane acid compound is a salt compound of lead, cobalt or zinc cyclopentane, and the other polar non-hydrocarbon compound is a sulfonic acid functionalized B acidic ionic liquid or chloroaluminate ionic liquid; the total amount of the catalyst is 0.3% to 1% of the total mass of the heavy component of the ethylene tar.

[0032] Further preferably, the stirring speed of the reactor in step S2 is 1000-6000 r / min.

[0033] Further preferably, the separation process in step S3 includes three stages, the temperature of the heavy component material entering the secondary separation process is greater than 120°C, and the temperature of the heavy component material entering the tertiary separation process is greater than 300°C.

[0034] According to the reaction process, the final high-softening-point coated asphalt has a softening point of 220°C~260°C, a coking value ≥70%, and a yield ≥65%.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The reactor and ethylene tar polymerization reaction device disclosed in the present invention can improve the uniformity of the ethylene tar catalytic reaction, including the uniformity of materials and temperature, and prevent material backmixing, thereby improving the uniformity of the ethylene tar catalytic reaction, thereby precisely controlling the degree of polymerization by precisely controlling the temperature and improving the product yield.

[0037] The present invention discloses an ethylene tar polymerization reaction process, which adopts a multi-stage polymerization reaction to further improve the uniformity of the reaction process, which is mainly reflected in the mixing degree of materials in each stage and the precise control of temperature in each reaction stage. While avoiding the shortcomings of intermittent operation such as long auxiliary time for heating and cooling the temperature and the failure to reasonably utilize energy, it also strengthens the reaction process, improves the reaction efficiency, and achieves the effect of increasing the coking value and yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0039] Figure 1 is a schematic diagram of an ethylene tar polymerization reaction apparatus used in an embodiment of the present invention;

[0040] Figure 2 Schematic diagram of a reactor used in an embodiment of the present invention;

[0041] In the picture:

[0042] Mixing tank 1;

[0043] Reactor 2, body 21, material inlet 211, material outlet 212, stirring element 22, impeller 221, coil heat exchanger 23, heat medium inlet 231, heat medium outlet 232, orifice plate 24;

[0044] Separation tank 3, separation feed port 31, light component discharge port 32, heavy component discharge port 33. DETAILED DESCRIPTION

[0045] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0046] In the following examples, Figure 1 An ethylene tar polymerization reaction device is shown to achieve this;

[0047] The reaction device includes a stirring tank 1; a three-stage reactor 2, the output end of the stirring tank 1 is connected to the material inlet of the first-stage reactor 2, and the three-stage reactors 3 are connected in series; and a three-stage separation tank 3 is further provided. Each stage of the separation tank 3 includes a separation feed port 31, a light component discharge port 32, and a heavy component discharge port 33. The material outlet of the last stage of the reactor 2 is connected to the separation feed port of the first-stage separation tank 3, and the heavy component discharge port of each stage of the separation tank 3 is connected to the separation feed port of the next stage of the separation tank 3.

[0048] like Figure 2 , wherein the reactor 2 at each stage includes a body 21, which is provided with a material inlet and a material outlet; further includes stirring elements 22 and coil-type heat exchangers 23 alternately arranged in the extension direction of the body 21; further includes a heat medium inlet 231 and a heat medium outlet 232 corresponding to each coil-type heat exchanger 23; further includes a perforated plate 24 arranged between two coil-type heat exchangers 23; each stirring element 22 includes two impellers 221, the two impellers 221 of each stirring element 22 face opposite directions, each perforated plate 24 corresponds to each stirring element 22, and the perforated plate 24 is placed between the two impellers 221 of the stirring element 22.

[0049] In the following examples, the ethylene tar heavy component is obtained by purifying and distilling industrial naphthalene-free ethylene tar, and the naphthalene-free ethylene tar has an Ennoisomer initial boiling point (IBP) ≥ 170°C and a final boiling point (FBP) ≤ 680°C.

[0050] In the following examples, the catalyst consists of undecylbenzenesulfonic acid (30 wt %), C20 unsaturated fatty acid (30 wt %), and sulfonic acid functionalized B acidic ionic liquid (40 wt %).

[0051] In the following examples, the temperature of the primary reactor is controlled by thermal oil, and the temperatures of the secondary and tertiary reactors are controlled by molten salt; the molten salt is a mixture of potassium nitrate (53 wt%), sodium nitrite (40 wt%), and sodium nitrate (7 wt%).

[0052] Example 1

[0053] In this example, the ethylene tar heavy component and catalyst were uniformly stirred or preheated at 180°C. The material flow rate into reactor 2 was 88 kg / h. The volume of each reactor 2 was 100 L, and the volume of each reactor 2 was 80 L (approximately 88 kg of material). The catalyst was added in an amount of 0.45 kg (approximately 0.5% by mass). The reaction time in reactor 2 was 480 minutes, and the reaction pressure in each reactor 2 was 1 MPa(G). Specifically, the reaction temperature of the first reactor 2 was 240°C, the reaction temperature of the second reactor 2 was 320°C, and the reaction temperature of the third reactor 2 was 380°C. The stirring speed of each reactor 2 was 3000 r / min, and the materials were continuously fed into and out of the third reactor 2. The ethylene tar catalytic polymerization product discharged from reactor 2 was then fed into a subsequent deep vacuum separation section to ultimately produce a high-softening-point coated asphalt. The deep vacuum separation operation temperature was 380°C and the operating pressure was -0.1 MPa(G).

[0054] About 65.7 kg of high softening point coated asphalt was obtained, with a yield of about 74.7%. After analysis and testing, the product indicators are shown in the following table:

[0055]

[0056] Example 2

[0057] The reaction was carried out according to the conditions and steps described in Example 1, except that the operating temperature of each stage of the reactor 2 was lowered. In this embodiment, the reaction temperature of the first stage reactor 2 was 200°C, the reaction temperature of the second stage reactor 2 was 300°C, and the reaction temperature of the third stage reactor 2 was 350°C.

[0058] About 59.6 kg of high softening point coated asphalt was obtained, with a yield of about 67.8%. After analysis and testing, the product indicators are shown in the following table:

[0059]

[0060] Example 3

[0061] The reaction was carried out according to the conditions and steps described in Example 1, except that the operating pressure of each stage of the reactor 2 was reduced; wherein, the reaction pressure of each stage of the reactor 2 was 0.8 MPa (G).

[0062] About 66.9 kg of high softening point coated asphalt was obtained, with a yield of about 76.0%. After analysis and testing, the product indicators are shown in the following table.

[0063]

[0064] Example 4

[0065] The reaction was carried out according to the conditions and steps described in Example 1, except that the reaction residence time was extended; wherein, in this example, the reaction time of the reaction materials in the three-stage reactor 2 was 600 minutes.

[0066] About 71.5 kg of high softening point coated asphalt was obtained, with a yield of about 81.3%. After analysis and testing, the product indicators are shown in the following table:

[0067]

[0068] Example 5

[0069] The reaction was carried out according to the conditions and steps described in Example 1, except that the amount of catalyst was increased; wherein the added mass of the catalyst was 0.9 kg (mass content of about 1%).

[0070] About 70.8 kg of high softening point coated asphalt was obtained, with a yield of about 80.5%. After analysis and testing, the product indicators are shown in the following table:

[0071]

[0072] This application also provides comparative examples:

[0073] In this comparative example, traditional single-pot thermal polymerization was used for the reaction. The volume of the reactor was 100 L, the total amount of reaction materials was 80 L (about 88 kg of materials), the mass of catalyst added was 0.45 kg (mass content was about 0.5%), the reaction time of the reaction materials in the reactor was 480 minutes, the reaction pressure was 1 MPa (G), the reactor temperature was 320°C, the reactor stirring speed was 3000 r / min, and the reaction products entered a short-path distiller for separation treatment. The temperature of the short-path distiller was controlled at 320°C using molten salt. The obtained separated products were collected into a product tank and then granulated.

[0074] 45.0 kg of high softening point asphalt was obtained, with a product yield of about 51.1%. After analysis and testing, the product indicators are shown in the following table:

[0075]

[0076] The product indicators obtained in Examples 1 to 5 and the comparative examples are summarized in Table 1:

[0077] Table 1 Summary of product indicators of various embodiments

[0078]

[0079] It can be seen from Table 1 that Examples 1 to 5 achieve a significant increase in coking value and yield compared to the comparative example, and have great advantages and economic benefits.

[0080] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0081] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. An ethylene tar polymerization reaction device, characterized in that: Including: stirring tank; reactor, The reactor is a stirred tower polymerization reactor, which comprises: a body, on which a material inlet and a material outlet are provided; and stirring elements and coil-type heat exchangers alternately arranged in the extending direction of the body; and a heat medium inlet and a heat medium outlet corresponding to each of the coil heat exchangers; and a perforated plate arranged between two of the coil-type heat exchangers; The output end of the stirring tank is connected to the material inlet of the first-stage reactor, and the reactors of several stages are connected in series; And several levels of separation tanks, each level of the separation tank includes a separation feed port, a light component discharge port and a heavy component discharge port, the material outlet of the last level of the reactor is connected to the separation feed port of the first level of the separation tank, and the heavy component discharge port of each level of the separation tank is connected to the separation feed port of the next level of the separation tank.

2. An ethylene tar polymerization reaction device according to claim 1, characterized in that: Each stirring member includes two impellers, the two impellers of each stirring member face opposite directions, each orifice plate corresponds to each stirring member one by one, and the orifice plate is placed between the two impellers of the stirring member.

3. An ethylene tar polymerization process, characterized in that: The ethylene tar polymerization reaction device according to claim 1 or 2 comprises the steps of: S1. uniformly stirring the ethylene tar heavy component and the catalyst; S2 continuously carries out multi-stage catalytic polymerization reaction, the catalytic polymerization reaction reactor used is a reactor according to claim 1 or 2 of the several stages; S3. Multi-stage separation to obtain a liquid phase ethylene tar catalytic polymerization product; S4. The high softening point coated asphalt is obtained by vacuum separation treatment.

4. An ethylene tar polymerization process according to claim 3, characterized in that: The ethylene tar heavy component is obtained by purifying and distilling industrial naphthalene-free ethylene tar. The Ennium initial boiling point (IBP) of the naphthalene-free ethylene tar is ≥170°C and the Ennium final boiling point (FBP) is ≤680°C.

5. An ethylene tar polymerization process according to claim 4, characterized in that, In the step S2, the multi-stage catalytic polymerization reaction is carried out at a pressure of 0.5 to 3 MPa, a total time of 5 to 10 hours, and a temperature of 180° C. to 410° C., and comprises the steps of: S2a. a first-stage catalytic polymerization reaction at a reaction temperature of 180° C. to 300° C.; S2b. Secondary catalytic polymerization reaction, the reaction temperature is 300 ℃ ~ 360 ℃; S2c. Three-stage catalytic polymerization reaction, the reaction temperature is 360℃~410℃.

6. The ethylene tar polymerization process according to claim 5, characterized in that: Before the continuous multi-stage catalytic polymerization reaction in step S2, the method further comprises: S1. Preheating treatment: preheating the ethylene tar heavy component to a temperature of 160°C to 200°C.

7. An ethylene tar polymerization process according to claim 6, characterized in that: The catalyst in step S1 is composed of an organic solvent mixture of alkylbenzene sulfonic acid, unsaturated fatty acid, petroleum naphthenic acid compound and other polar non-hydrocarbon compounds, and the content of each compound in the catalyst is between 10% and 50%; Wherein, the alkylbenzenesulfonic acid compound is one or more of undecylbenzenesulfonic acid, linear dodecylbenzenesulfonic acid, branched dodecylbenzenesulfonic acid, and tetracosylbenzenesulfonic acid; the unsaturated fatty acid is one or more of C14 to C24 unsaturated fatty acids; the petroleum naphthenic acid compound is a salt compound of lead, cobalt, or zinc naphthenate; and the other polar non-hydrocarbon compound is a sulfonic acid functionalized B acidic ionic liquid or a chloroaluminate ionic liquid; The total amount of the catalyst is 0.3% to 1% of the total mass of the ethylene tar heavy components.

8. The ethylene tar polymerization process according to claim 5, wherein: The stirring speed of the reactor in step S2 is 1000-6000 r / min.

9. The ethylene tar polymerization process according to claim 5, wherein: The separation process in step S3 includes three stages. The temperature of the heavy component material entering the secondary separation process is greater than 120° C., and the temperature of the heavy component material entering the tertiary separation process is greater than 300° C.

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