Method and system for treating slag slurry product after fluidized bed hydrogenation

Abstract

The invention relates to a method and system for treating a slurry product after fluidized bed hydrogenation, and belongs to the field of fluidized bed hydrogenation, hydrogen is introduced into the slurry product and atomized to form small liquid drops, then a coking reaction is carried out, coke, light hydrocarbon and impurity gas are obtained, the hydrogen is introduced into the slurry product in two times, the first time is introduced in a microbubble form before atomization, and the second time is introduced in a microbubble form before atomization; the microbubbles stably exist in the slag slurry product; the gas is introduced in the form of gas flow during secondary atomization, an included angle alpha is formed between the flow direction of the gas and the flow direction of the slag slurry product, and alpha is more than 90 degrees and less than or equal to 180 degrees. According to the method, the slag slurry product and the hydrogen are mixed, atomized and subjected to the coking reaction, so that the slag slurry product serving as waste is converted into the light hydrocarbon product and the coke product to be sold, effective utilization of the waste is achieved, the additional value of the product is improved, and the yield of the light hydrocarbon is increased.

Description

Technical Field

[0001] The present invention relates to the field of ebullated bed hydrogenation, and specifically to a method and system for treating the slurry product after ebullated bed hydrogenation. Background Art

[0002] With the rapid development of the global economy, the rapid growth in the demand for light and clean fuel oils, and the increasingly poor quality of crude oil with a higher content of heavy components, how to effectively utilize non-renewable petroleum resources, achieve the maximum lightening of residue oil, and produce high-value petroleum products is an important issue currently faced.

[0003] Currently, the general methods for treating residue oil are hydrogenation and decarbonization. The decarbonization process has low equipment investment, but low liquid product yield and poor properties; the hydrogenation process has better product quality and high liquid yield, but high investment due to the use of high-pressure reaction equipment. The currently relatively mature residue oil hydrogenation technology is fixed-bed residue oil hydrogenation, but this process is restricted by the properties of the raw materials and has relatively strict requirements for indicators such as the metal and carbon residue of the raw materials; while the ebullated bed residue oil hydrogenation process has a wide adaptability to raw materials and is attracting more and more attention.

[0004] Whether it is residue oil or heavy oil, when undergoing a hydrogenation reaction in an ebullated bed, in addition to obtaining gas-phase products and conventional liquid-phase products, viscous slurry products that cannot be utilized will also be generated. These slurry products have very complex compositions and high heavy metal contents, making them difficult to process. The currently commonly used method is the heat treatment method, which decomposes and oxidizes the organic matter in the slurry by heating to convert it into harmless substances. This method has limited effects and requires a large amount of energy and time. Summary of the Invention

[0005] The purpose of the present invention is to provide a method and system for treating the slurry product after ebullated bed hydrogenation. The treatment method and system mix the slurry product with hydrogen, atomize it, and carry out a coking reaction, thereby converting the waste slurry product into light hydrocarbon products and coke products for sale. This not only realizes the effective utilization of waste, improves the added value of the products, but also increases the yield of light hydrocarbons.

[0006] The technical solution adopted by the present invention to achieve the above technical purpose is: a method for treating the slurry product after ebullated bed hydrogenation, introducing hydrogen into the slurry product, atomizing it to form small droplets, and then carrying out a coking reaction to obtain coke, light hydrocarbons, and impurity gases. The hydrogen is introduced into the slurry product in two times. The first time is introduced in the form of microbubbles before atomization and makes the microbubbles stably exist in the slurry product; the second time is introduced in the form of an air flow during atomization, and an included angle α is formed between the gas flow direction and the flow direction of the slurry product, where 90° < α ≤ 180°.

[0007] As an optimized solution for the treatment method of the slurry product after ebullated bed hydrogenation, after the first introduction of hydrogen microbubbles, during the flow of the mixed phase formed by the slurry product and the microbubbles, the flow direction of part of the fluid changes to alter the distribution state of the microbubbles in the mixed phase, and then atomization is carried out.

[0008] As another optimized solution for the treatment method of the slurry product after ebullated bed hydrogenation, the conditions for the coking reaction are a reaction temperature of 500 °C and a pressure of 0.5 MPa.

[0009] As another optimized solution for the treatment method of the slurry product after ebullated bed hydrogenation, the mass of hydrogen introduced in the first time in the form of microbubbles is 1 - 8% of the slurry product, the mass of hydrogen introduced in the second time in the form of a gas stream is 0.5 - 2% of the slurry product, and the mass of hydrogen introduced in the first time is greater than the mass of hydrogen introduced in the second time. The flow rate of hydrogen introduced in the second time is 80 - 200% of the flow rate of the slurry product.

[0010] A treatment system for the slurry product after ebullated bed hydrogenation includes a premixing device for preliminarily mixing the slurry product and hydrogen, a coking furnace for carrying out the coking reaction, and an atomization mechanism for atomizing and spraying the mixture formed by the slurry product and hydrogen into the coking furnace. The premixing device has a slurry pipeline and a microbubble generator connected to the primary hydrogen pipeline, so that hydrogen is mixed with the slurry product in the form of microbubbles; the atomization mechanism is provided with a secondary hydrogen pipeline, so that hydrogen in the form of a gas stream intersects and mixes with the slurry with microbubbles in the atomization mechanism, and then is atomized and sprayed into the coking furnace.

[0011] As an optimized solution for the treatment system for the slurry product after ebullated bed hydrogenation, the premixing device is a cylinder with openings at both ends. One end is connected to the slurry pipeline to form a liquid inlet, and the end opposite to the liquid inlet forms a discharge port. The area between the liquid inlet and the discharge port forms a mixing flow chamber. Along the flow direction of the slurry, the inner diameters of the liquid inlet and the discharge port gradually decrease, and a clamping platform is formed at the connection between the liquid inlet and the mixing flow chamber. The microbubble generator is located in the mixing flow chamber.

[0012] As another optimized solution for the treatment system for the slurry product after ebullated bed hydrogenation, the atomization mechanism has a cavity and a spray outlet. A spiral air guide plate is arranged around the inner side wall of the cavity. One side edge of the air guide plate is fixed to the inner wall of the cavity, and the other side is inclined upward and forms a gas guide area with an opening facing the incoming flow direction with the cavity side wall. The secondary air supply pipe extends into the gas guide area, so that the continuous gas phase discharged by it spirally rises along the gas guide area and impacts and mixes with the gas-liquid mixed flow in the cavity.

[0013] As another optimized solution for the treatment system of the slurry product after ebullated bed hydrogenation, the premixing device is connected to the atomization mechanism through an L-shaped mixed-phase discharge pipeline, and a buffer is provided at the corner of the mixed-phase discharge pipeline;

[0014] The buffer is L-shaped and consists of a horizontal pipe section and a vertical pipe section. The horizontal pipe section has equal-diameter holes, and the inner diameter of one end of the equal-diameter holes gradually increases to form a gradually expanding part. A baffle area is formed at the connection between the gradually expanding part and the inner cavity of the vertical pipe section. An elastic fragmentation plate is arranged in the inner cavity of the vertical pipe section.

[0015] As another optimized solution for the treatment system of the slurry product after ebullated bed hydrogenation, a baffle is inclinedly arranged on the side wall of the inner cavity of the vertical pipe section. The free end of the baffle extends into the baffle area after exceeding the gradually expanding part and forms a diversion area for changing the flow direction of the gas-liquid mixed flow with the gradually expanding part.

[0016] As another optimized solution for the treatment system of the slurry product after ebullated bed hydrogenation, a baffle plate is arranged between the baffle and the elastic fragmentation plate, and the baffle plate and the baffle are located on both sides of the axis of the vertical pipe section. The baffle plate is fixed on the side wall of the inner cavity of the vertical pipe section, and the free end is inclined towards the oncoming flow direction and forms an acute angle with the inner wall of the vertical pipe section with the opening facing the oncoming flow direction.

[0017] As another optimized solution for the treatment system of the slurry product after ebullated bed hydrogenation, a conical liquid guide cylinder is arranged on the side wall of the inner cavity of the vertical pipe section. The large-diameter end of the conical liquid guide cylinder is fixed to the vertical pipe section, and the small-diameter end is open and faces the elastic fragmentation plate.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1) After mixing the slurry product of the ebullated bed hydrogenation reaction with hydrogen, atomizing and carrying out a coking reaction, the present invention transforms the slurry product as waste into light hydrocarbon products and coke products for sale, which not only realizes the effective utilization of waste, improves the added value of products, but also increases the yield of light hydrocarbons. It has been proved by experiments that the yield of light hydrocarbons can be increased by 2-10%;

[0020] 2) Due to the extremely high viscosity of the slurry product, the atomization effect of conventional atomization methods is very poor. If the slurry product is directly fed into the coking furnace without sufficient atomization, it will lead to a decrease in the reaction efficiency with hydrogen, and the yield of light hydrocarbons will also decrease accordingly. Based on the existing "microbubble + liquid-phase mixing + atomization spraying", the present invention introduces a secondary hydrogen gas flow, and makes the secondary hydrogen gas flow counter-flow and mix with the slurry product containing mixed microbubbles, so that during the process of atomization spraying of the slurry product, the microbubbles contained in the ejected micro-droplets can quickly undergo secondary explosion, further dispersing the size of the micro-droplets, and making the droplets once dispersed by atomization be broken, refined, and dispersed again;

[0021] 3) In order to further improve the atomization effect, the present invention adds a buffer between the microbubble generator and the atomization mechanism, so that the slurry product containing microbubbles does not directly spray out by atomization, but enters the buffer. Since the buffer is L-shaped and has a gradually expanding part, a baffle area, and an elastic fragmentation plate inside, when the slurry product containing microbubbles enters the gradually expanding part, due to the gradually increasing inner diameter and just being at the corner, the overall flow direction of the slurry product changes and adjusts to varying degrees, and a confluence occurs in the baffle area. Finally, it impacts on the elastic fragmentation plate, and the flow direction changes again. During the process of flow direction change and confluence, the distribution of microbubbles in the slurry product and the thickness of the liquid film between microbubbles are changed. Then, it counter-flows with the continuous hydrogen gas flow supplemented by the secondary gas supply pipe, changing the thickness of the liquid film between microbubbles, and during the atomization spraying process, the microbubbles undergo secondary explosion, thereby causing "secondary" dispersion of the micro-droplets and improving the dispersion effect of the slurry product;

[0022] 4) In order to further change the distribution characteristics of microbubbles in the slurry product, a baffle plate with its top extending into the baffle area is arranged in the buffer of the present invention. By relying on the baffle plate, the flow state of part of the slurry product is further changed, so that the slurry product impacts itself during the flow process; and a baffle is arranged between the baffle plate and the elastic fragmentation plate, which can strengthen the internal impact effect of the gas-liquid emulsion phase oil; in addition, the presence of the conical liquid guide cylinder can guide the gas-liquid emulsion phase oil to impact on the fragmentation plate, thereby enhancing the vibration effect of the fragmentation plate and generating partial backflow. This part of the backflow deviates from the flow direction of the gas-liquid emulsion phase oil, thereby improving the internal impact effect of itself and promoting the secondary irregular distribution of microbubbles in the gas-liquid emulsion phase oil;

[0023] 5) In order to improve the counter-flow effect between the secondary hydrogen gas flow and the slurry product, the present invention arranges a spiral-shaped air guiding plate in the cavity of the atomization mechanism. The secondary hydrogen gas flow spirally ascends along the spiral groove formed by the air guiding plate and the inner wall of the cavity, and during this process, it counter-flows and mixes with the slurry product flowing from top to bottom. At the same time, the air guiding plate can also change the flow distribution of the slurry product inside the cavity, improving the mixing effect between the hydrogen gas flow and the slurry product. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic structural diagram of the system of the present invention;

[0025] Figure 2 It is a schematic structural diagram of the premixing device in the present invention;

[0026] Figure 3 It is a schematic structural diagram of the atomization mechanism in the present invention;

[0027] Figure 4 It is another schematic structural diagram of the system of the present invention;

[0028] Figure 5 is Figure 4 a schematic structural diagram of the buffer in;

[0029] Reference numerals: 1, premixing device; 101, slurry pipeline; 102, primary hydrogen pipeline; 103, mixed-phase discharge pipeline; 104, liquid inlet; 105, mixing chamber; 106, discharge port; 2, secondary hydrogen pipeline; 3, coking furnace; 4, atomization mechanism; 401, secondary gas supply pipe; 402, cavity; 403, spray outlet; 404, air guide plate; 405, gas guide area; 5, buffer; 501, horizontal pipe section; 502, vertical pipe section; 503, equal-diameter hole; 504, gradually expanding part; 505, baffle area; 506, baffle plate; 507, diversion area; 508, conical liquid guide cylinder; 509, elastic fragmentation plate; 5010, baffle plate. Detailed implementation manners

[0030] The technical solutions of the present invention will be further elaborated in detail below in conjunction with specific embodiments. For parts not elaborated in the following embodiments of the present invention, such as the specific structure of the microbubble generator, parameters such as the mixing ratio and flow rate of the slurry product and hydrogen, the parameters of the continuous hydrogen flow charged into the secondary gas supply pipe, and the structures of other auxiliary structures of the system for pressurizing the slurry product and hydrogen, are all regarded as the prior art known or should be known to those skilled in the art.

[0031] Embodiment 1

[0032] A method for treating the slurry product after ebullated bed hydrogenation, hydrogen is introduced into the slurry product. Generally, pressure is applied to the slurry product so that it is mixed with hydrogen during the flow in the pipeline and atomized into small droplets for coking reaction. Existing atomization equipment can be used for atomization. The equipment for coking reaction is generally a coking furnace. The conditions and parameters of the coking reaction are adjusted according to the actual situation to obtain coke, light hydrocarbons and impurity gases. The impurity gases can be discharged after treatment. The hydrogen is introduced into the slurry product in two times. And the first time is introduced in the form of microbubbles before atomization. Generally, with the help of existing microbubble generators, hydrogen is formed into microbubbles and mixed with the slurry product. The mixing ratio can be adjusted according to the actual situation, generally 1-8% of the mass of the slurry product, preferably 2-5%. And make the microbubbles stably exist in the slurry product. The second time is introduced in the form of gas flow during atomization, that is, hydrogen is directly introduced into the slurry product through the pipeline. At this time, the introduced mass of hydrogen is less than the mass of hydrogen introduced for the first time. The ratio is generally 0.5-2% of the mass of the slurry product, preferably 0.5-1%. The flow rate of the hydrogen flow is generally 80-200% of the flow rate of the slurry product, preferably 100-150%. And an included angle α is formed between the gas flow direction and the flow direction of the slurry product, 90° < α ≤ 180°, and the angle of α is preferably 160-180°.

[0033] In this embodiment, the reaction temperature of the coking reaction is 500 °C and the pressure is 0.5 MPa.

[0034] The above is the basic implementation mode of the present invention. Further improvements, optimizations and limitations can be made on this basis to obtain the following embodiments:

[0035] Embodiment 2

[0036] In order to improve the distribution state of hydrogen microbubbles in the slurry product so that they can burst during atomization and improve the atomization effect, the following optimizations can be made on the basis of Embodiment 1: After the hydrogen microbubbles are introduced into the slurry product for the first time, during the flow of the mixed phase formed by the slurry product and the microbubbles, the flow direction of some fluids is changed. Generally, pipelines, containers, etc. are used to make the mixed phase collide with the attached structures or side walls in the pipelines and containers during the process of passing through these pipelines and containers to generate a flow deflection, or the flow direction of some fluids is changed and then intersects and collides with other parts of the fluids to change the distribution state of the microbubbles in the mixed phase. Then atomization is carried out, and hydrogen flow is introduced in the form of gas flow during atomization to make it collide and mix with the slurry product.

[0037] Embodiment 3

[0038] A treatment system for the slurry product after ebullated bed hydrogenation, as Figure 1As shown in the figure, it includes a premixing device 1 for preliminarily mixing the slurry product and hydrogen, a coking furnace 3 for carrying out the coking reaction, and an atomization mechanism 4 for atomizing the mixture formed by the slurry product and hydrogen and spraying it into the coking furnace 3. In this embodiment, the coking furnace 3 and the atomization mechanism 4 can directly use commercially available coking furnaces and atomization nozzles, so their structures and models will not be elaborated. Green hydrogen produced by electrolyzing water is preferably selected for hydrogen; in the premixing device 1, there is a slurry pipeline 101 and a microbubble generator communicated with the primary hydrogen pipeline 102, so that hydrogen is mixed with the slurry product in the form of microbubbles. In this embodiment, a commercially available microbubble generator can be selected as the microbubble generator. Its purpose is to form microbubbles of hydrogen to mix with the slurry product. The size of the microbubbles is preferably below 30 microns, and hydrogen is preferably made to stably exist in the slurry product in the form of microbubbles; on the atomization mechanism 4, there is a secondary hydrogen pipeline 2, and hydrogen is continuously introduced into the atomization mechanism 4 through the secondary hydrogen pipeline 2, so that hydrogen intersects and mixes and collides with the slurry with microbubbles in the form of an air flow in the atomization mechanism 4, and then is atomized into small droplets containing microbubbles and sprayed into the coking furnace 3.

[0039] In this embodiment, the premixing device 1 is a metal cylinder with both ends open. One end is connected to the slurry pipeline 101 to form a liquid inlet 104, and the end opposite to the liquid inlet 104 forms a discharge port 106. The area between the liquid inlet 104 and the discharge port 106 forms a mixing chamber 105. Along the slurry flow direction, the inner diameters of both the liquid inlet 104 and the discharge port 106 gradually decrease. The shapes of both the liquid inlet 104 and the discharge port 106 are conical. Generally, the ratio of the large diameter end to the small diameter end of the liquid inlet 104 is 10 - 20:1, and its length accounts for 10 - 20% of the total length of the cylinder. The inner diameter of the small diameter end of the liquid inlet 104 is generally 3 - 8 mm; generally, the ratio of the large diameter end to the small diameter end of the discharge port 106 is 5 - 10:1, and its length accounts for 20 - 30% of the total length of the cylinder. The inner diameter of the small diameter end of the discharge port 106 is generally 5 - 10 mm, and a clamping platform is formed at the connection between the liquid inlet 104 and the mixing chamber 105. The cross-section of the clamping platform is right-angled, and one right-angled side forms the demarcation line of the mixing chamber 105, and the hypotenuse forms the side wall of the liquid inlet 104; the microbubble generator is located in the mixing chamber 105 to mix hydrogen and the slurry in the mixing chamber 105; the unique design of the liquid inlet 104 causes the slurry to produce a jet dispersion effect when entering the mixing chamber 105 through the liquid inlet 104 because the space suddenly shrinks and then expands, and then is fully mixed with hydrogen microbubbles in the mixing chamber 105; the design of the discharge port 106 makes it difficult for the slurry to be quickly discharged, thus producing a pressure increasing effect in the mixing chamber 105, promoting the full mixing of hydrogen microbubbles and the slurry and stably existing.

[0040] Example 4

[0041] This embodiment is an improved solution for the atomization mechanism 4 based on Embodiment 3. Its main structure is the same as that of Embodiment 3. The improvement lies in that the atomization mechanism 4 can adopt an existing atomizing nozzle, but a secondary air supply pipe 401 needs to be added to the atomizing nozzle. However, the following structure is preferably adopted, as Figure 3 shown, that is, it has a cavity 402 and a jet outlet 403. The cavity 402 is used to communicate with the mixed-phase discharge pipeline 103, so that the gas-liquid mixed flow enters the cavity 402 and is ejected through the jet outlet 403. The cavity 402 is generally a cylindrical cavity. A spiral air guiding plate 404 is arranged around the inner side wall of the cavity 402. One side edge of the air guiding plate 404 is fixed to the inner wall of the cavity 402, and the other side is inclined upward, forming a gas guiding area 405 with an opening facing the oncoming flow direction with the cavity side wall. In practice, the air guiding plate 404 is a spiral plate. When viewed from the horizontal direction, the projection of the air guiding plate 404 in the vertical direction is an inclined straight plate, and the acute angle formed between it and the inner wall of the cavity 402 is generally 20-60°. The distance between its edge and the inner wall of the cavity 402 is generally 10-20% of the diameter of the cavity 402. The finally formed gas guiding area 405 is actually a spiral groove, and the depth of the groove is generally greater than the air inlet of the secondary air supply pipe 401 for introducing the continuous-phase gas. In practice, the secondary air supply pipe 401 is an inclined hole opened on the inner side wall of the cavity 402, and the diameter of the inclined hole is less than half of the groove depth. The secondary air supply pipe 401 extends into the gas guiding area 405. The secondary air supply pipe 401 is at one end of the gas guiding area 405 close to the jet outlet 403. The axis of the secondary air supply pipe 401 can be perpendicular to the axis of the cavity 402, or can form a certain acute or obtuse angle with the axis of the cavity 402. Preferably, the secondary air supply pipe 401 is perpendicular to the axis of the cavity 402 and injects the continuous-phase gas along the tangent direction of the cavity 402. At the same time, the injection direction of the gas is away from the spiral direction of the air guiding plate 404, so that the gas moves along the spiral air guiding plate 404 in the direction away from the jet outlet 403, so that the discharged continuous gas phase collides and mixes with the gas-liquid mixed flow in the cavity 402 during the spiral upward movement along the gas guiding area 405;

[0042] In this embodiment, the cavity 402 is an integral structure formed by splicing a hollow cylindrical area and a conical area. The central axes of the cylindrical area and the conical area overlap. The diameter of the cylindrical area is equal to the large-diameter end of the conical area, and one end is connected to the large-diameter end of the conical area, and the other end is communicated with the mixed-phase discharge pipeline 103, so that the gas-liquid mixed flow enters the cavity 402. The jet outlet 403 is at the bottom tip position of the conical area. The air guiding plate 404 is distributed on the inner side wall of the cylindrical area, and both ends of the air guiding plate 404 do not extend beyond the upper and lower end faces of the cylindrical area. The secondary air supply pipe 401 is at the position of the gas guiding area 405 close to the jet outlet 403 and is within the angle formed by the air guiding plate 404 and the side wall of the cylindrical area.

[0043] Example 5

[0044] This embodiment is another improved solution based on Embodiment 3. Its main structure is the same as that of Embodiment 3. The improvement lies in that, as Figure 4 shown, the premixing device 1 is connected to the atomization mechanism 4 through an L-shaped mixed-phase discharge pipeline 103. The atomization mechanism 4 can adopt an existing atomizing nozzle, but only a secondary air supply pipe 401 needs to be added to the atomizing nozzle, or the atomization mechanism in Embodiment 4 can also be adopted; a buffer 5 is provided at the corner of the mixed-phase discharge pipeline 103;

[0045] The buffer 5 has an L-shaped hollow tubular structure, which is formed by connecting the end of a horizontal pipe section 501 and a vertical pipe section 502 integrally. The outer diameters of the horizontal pipe section 501 and the vertical pipe section 502 are generally the same, and the axes of the two are perpendicular to each other. The horizontal pipe section 501 has an equal-diameter hole 503. The equal-diameter hole 503 is located at the center of the horizontal pipe section 501. One end of the equal-diameter hole 503 forms the opening of the buffer 5, and the inner diameter of the other end gradually increases to form a gradually expanding portion 504. In fact, the equal-diameter hole 503 and the gradually expanding portion 504 constitute the continuous inner cavity of the horizontal pipe section 501, and a baffle area 505 is formed at the connection between the gradually expanding portion 504 and the inner cavity of the vertical pipe section 502. The baffle area 505 is actually the connection of two mutually perpendicular pipe sections, and its inner cavity also has a right-angled corner. The inner cavity outlet of the vertical pipe section 502 forms the outlet of the buffer 5. An elastic crushing plate 509 is provided in the inner cavity of the vertical pipe section 502, and the elastic crushing plate 509 does not affect the outflow of the mixed phase.

[0046] In this embodiment, the elastic crushing plate 509 can be selected from conventional metal plates, which can be drilled or not drilled. There is a gap between the edge of the metal plate and the inner wall of the vertical pipe section 502, and it is fixed on the inner wall of the vertical pipe section 502 through an elastic member, such as a spring; the elastic crushing plate 509 is preferably a Johnson screen made of metal, and is also fixed on the inner wall of the vertical pipe section 502 through an elastic member. The metal wires forming the Johnson screen generally select conventional sizes, preferably 4.0 and 4.5 mm, and the width of the mesh holes on the surface generally does not exceed 1 mm. The shape of the Johnson screen is a circle identical to the shape of the inner cavity of the vertical pipe section 502, and the two are coaxial, and its edge is fixed on the side wall of the inner cavity of the vertical pipe section 502 through an elastic member, so as to form an annular baffle channel between its edge and the inner wall of the vertical pipe section 502. The width of the annular baffle channel, that is, the distance between the edge of the Johnson screen and the inner wall of the vertical pipe section 502, is generally 20-30% of the radius of the inner cavity of the vertical pipe section 502.

[0047] On the side wall of the inner cavity of the vertical pipe section 502, a baffle plate 506 is inclinedly arranged. The baffle plate 506 is preferably made of an erosion-resistant alloy material, and forms an angle of 40-60° with the inner wall of the vertical pipe section 502. The free end of the baffle plate 506 extends beyond the side wall extension line of the gradually expanding part 504 and extends into the baffle area 505. That is to say, there is a gap between the connection point of the baffle plate 506 and the vertical pipe section 502 and the intersection of the vertical pipe section 502 and the horizontal pipe section 501, and there is also a gap between the free end of the baffle plate 506 and the other side wall of the inner cavity of the vertical pipe section 502. That is, the baffle plate 506 cannot seal the inner cavity of the vertical pipe section 502. In practice, the baffle plate 506 is actually an arc-shaped plate, and its arc-shaped side is arranged close to the side wall of the inner cavity of the vertical pipe section 502. The projection of the straight side in the radial direction of the vertical pipe section 502 does not exceed the radius of the vertical pipe section 502, generally 20-40% of the inner diameter of the vertical pipe section 502, and forms a flow guiding area 507 for changing the flow direction of the gas-liquid mixed flow with the gradually expanding part 504;

[0048] In addition, in this embodiment, a baffle plate 5010 can also be arranged between the baffle plate 506 and the elastic fragmentation plate 509, as Figure 5 shown. The baffle plate 5010 is preferably made of an erosion-resistant alloy material, and forms an angle of 20-60° with the inner wall of the vertical pipe section 502. And the baffle plate 5010 and the baffle plate 506 are located on both sides of the axis of the vertical pipe section 502. The projections of the free ends of the baffle plate 5010 and the baffle plate 506 in the radial direction of the vertical pipe section 502 do not contact. The baffle plate 5010 is fixed on the side wall of the inner cavity of the vertical pipe section 502, and the free end is inclined towards the oncoming flow direction. The so-called oncoming flow direction refers to the flow direction of the gas-liquid mixed flow, and forms an acute angle with the inner wall of the vertical pipe section 502 with the opening facing the oncoming flow direction, so that part of the gas-liquid mixed flow forms a backflow in this acute angle. In practice, the baffle plate 5010 is actually an arc-shaped plate, and its arc-shaped side is arranged close to the side wall of the inner cavity of the vertical pipe section 502. The projection of the straight side in the radial direction of the vertical pipe section 502 does not exceed the radius of the vertical pipe section 502, generally 20-30% of the inner diameter of the vertical pipe section 502;

[0049] In addition, in this embodiment, a conical liquid guide cylinder 508 can also be arranged on the side wall of the inner cavity of the vertical pipe section 502, as Figure 5 shown. The conical liquid guide cylinder 508 is preferably a cylindrical structure with both ends open and made of an erosion-resistant alloy material. Its generatrix forms an angle of 120-160° with the inner wall of the vertical pipe section 502. The large-diameter end of the conical liquid guide cylinder 508 is fixed to the vertical pipe section 502, and the small-diameter end is open and faces the elastic fragmentation plate 509, so as to guide the gas-liquid mixed flow to impact on the elastic fragmentation plate 509. In practice, the diameter of the opening at the small-diameter end of the conical liquid guide cylinder 508 is generally 60-90% of the diameter of the elastic fragmentation plate 509.

[0050] To verify the specific effects of the present invention, the following comparative experiments were conducted:

[0051] Experiment content:

[0052] The properties of the selected heavy oil are as follows: the density is 0.978 g / cm 3 (20 °C), the kinematic viscosity is 3396 mm 2 / s (80 °C), 859.6 mm 2 / s (100 °C), the carbon residue content is 3.6%, the H content is 12.53%, and the S content is 0.22%;

[0053] The heavy oil and hydrogen were fed into a fluidized bed for fluidized bed hydrocracking reaction. The reaction temperature of the hydrocracking reaction was 400 °C, the hydrogen partial pressure was 15 MPa, and the overall volume space velocity was 0.15 h -1 , and finally a viscous slurry product was obtained as the experimental raw material;

[0054] Comparative Example 1

[0055] The experimental raw material was directly fed into a coking furnace and directly coked under the conditions of a reaction temperature of 500 °C and a pressure of 0.5 MPa to obtain coke and light hydrocarbon products. After detection, the yield of coke was 33.36%, and the yield of light hydrocarbons was 55.12%.

[0056] Comparative Example 2

[0057] The experimental raw material was mixed with 6% of its weight of hydrogen and then atomized through an atomizing nozzle and fed into the coking furnace. The diameter of the spray holes in the atomizing nozzle was 0.8 mm. After the experimental raw material was mixed with hydrogen, it was atomized and sprayed into the coking furnace at a pressure of 3 MPa. Under the conditions of a reaction temperature of 500 °C and a pressure of 0.5 MPa, it was directly coked to obtain coke and light hydrocarbon products. After detection, the yield of coke was 29.82%, and the yield of light hydrocarbons was 57.23%.

[0058] Comparative Example 3

[0059] The experimental raw material was mixed with 5% of its mass of hydrogen. This part of hydrogen was formed into a microbubble flow with a size not exceeding 30 microns by an existing microbubble generator and introduced into the experimental raw material to form a mixed phase. The mixed phase was sprayed into the coking furnace through the atomizing nozzle of Comparative Example 2. Synchronously, a hydrogen gas flow of 1% of the mass of the slurry was introduced into the atomizing nozzle, and the included angle formed by the flow direction of the hydrogen gas flow and the flow direction of the slurry in the atomizing nozzle was 160°;

[0060] Under the conditions of a reaction temperature of 500 °C and a pressure of 0.5 MPa, it was directly coked to obtain coke and light hydrocarbon products. After detection, the yield of coke was 21.56%, and the yield of light hydrocarbons was 63.71%

[0061] Comparative Example 4

[0062] On the basis of Comparative Example 3, the mixed phase formed by mixing the experimental raw materials with microbubbles first passes through the buffer 5 in Example 5, and then is sprayed into the coking furnace through the atomizing nozzle in Comparative Example 2. Synchronously, a hydrogen stream accounting for 1% of the mass of the slag slurry is introduced into the atomizing nozzle, and the included angle formed by the flow direction of the hydrogen stream and the flow direction of the slag slurry in the atomizing nozzle is 160°;

[0063] Under the conditions of a reaction temperature of 500 °C and a pressure of 0.5 MPa, coking is directly carried out to obtain coke and light hydrocarbon products. After detection, the yield of coke is 17.62%, and the recovery rate of light hydrocarbons is 67.19%.

[0064] Experimental conclusion:

[0065] It can be seen from the comparison between Comparative Example 1 and Comparative Example 2 that after the slag slurry product is mixed with hydrogen and then coked, the yield of coke slightly decreases, and the recovery rate of light hydrocarbons increases slightly;

[0066] It can be seen from the comparison between Comparative Example 2 and Comparative Example 3 that for the same hydrogen, first mixing microbubbles with the slag slurry and then introducing the remaining hydrogen during the atomizing spraying process can significantly reduce the coke yield and greatly increase the light hydrocarbon recovery rate;

[0067] It can be seen from the comparison between Comparative Example 3 and Comparative Example 4 that before atomizing spraying, after additionally setting the buffer 5, the coke yield further decreases, and the light hydrocarbon recovery rate is further improved.

Claims

1. A method for treating the slurry product after fluidized bed hydrogenation, comprising introducing hydrogen into the slurry product, atomizing it to form small droplets, and then carrying out a coking reaction to obtain coke, light hydrocarbons and impurity gases, characterized in that: The hydrogen gas is introduced into the slurry product in two times. The first time, it is introduced in the form of microbubbles before atomization and the microbubbles are stably present in the slurry product. The second time, it is introduced in the form of an air flow during atomization, and an angle α, 90° < α ≤ 180°, is formed between the gas flow direction and the flow direction of the slurry product.

2. The treatment method of the slurry product after ebullated bed hydrogenation according to claim 1, characterized in that: After the hydrogen microbubbles are introduced for the first time, during the flow of the mixed phase formed by the slurry product and the microbubbles, the flow direction of part of the fluid changes to change the distribution state of the microbubbles in the mixed phase, and then atomization is carried out.

3. The treatment method of the slurry product after ebullated bed hydrogenation according to claim 1, characterized in that: The reaction temperature of the coking reaction is 500 °C and the pressure is 0.5 MPa.

4. A method for treating the slurry product after ebullated bed hydrogenation according to claim 1, characterized in that: The mass of the hydrogen gas introduced in the form of microbubbles for the first time is 1-8% of the slurry product, and the mass of the hydrogen gas introduced in the form of an air flow for the second time is 0.5-2% of the slurry product. Moreover, the mass of the hydrogen gas introduced for the first time is greater than the mass of the hydrogen gas introduced for the second time, and the flow rate of the hydrogen gas introduced for the second time is 80-200% of the flow rate of the slurry product.

5. A treatment system for the slurry product after fluidized bed hydroprocessing, comprising a premixing device (1) for preliminarily mixing the slurry product with hydrogen, a coking furnace (3) for carrying out the coking reaction, and an atomization mechanism (4) for atomizing the mixture formed by the slurry product and hydrogen and spraying it into the coking furnace (3), characterized in that: In the premixing device (1), there is a slurry pipeline (101) and a microbubble generator communicated with the primary hydrogen gas pipeline (102), so that the hydrogen gas is mixed with the slurry product in the form of microbubbles; on the atomization mechanism (4), there is a secondary hydrogen gas pipeline (2), so that the hydrogen gas intersects and mixes with the slurry with microbubbles in the atomization mechanism (4) in the form of an air flow, and then is atomized and sprayed into the coking furnace (3).

6. The treatment system for the slurry product after ebullated bed hydrogenation according to claim 5, wherein: The premixing device (1) is a cylinder with openings at both ends. One end is connected to the slurry pipeline (101) to form a liquid inlet (104), and the end opposite to the liquid inlet (104) forms a discharge port (106). The area between the liquid inlet (104) and the discharge port (106) forms a mixing flow cavity (105). Along the slurry flow direction, the inner diameters of the liquid inlet (104) and the discharge port (106) both gradually decrease, and a clamping platform is formed at the connection between the liquid inlet (104) and the mixing flow cavity (105). The microbubble generator is located in the mixing flow cavity (105).

7. A treatment system for the slurry product after ebullated bed hydrogenation according to claim 5, characterized in that: The atomization mechanism (4) has a cavity (402) and a spray outlet (403). A spiral air guiding plate (404) is arranged around the inner side wall of the cavity (402). One side edge of the air guiding plate (404) is fixed to the inner wall of the cavity (402), and the other side is inclined upward and forms an air guiding area (405) with an opening facing the oncoming flow direction with the cavity side wall. The secondary air supply pipe (401) extends into the air guiding area (405), so that the continuous gas phase discharged by it impacts and mixes with the gas-liquid mixed flow in the cavity (402) during the spiral upward movement along the air guiding area (405).

8. The treatment system for the slurry product after ebullated bed hydrogenation according to claim 5, characterized in that: The premixing device (1) is communicated with the atomization mechanism (4) through an L-shaped mixed phase discharge pipeline (103), and a buffer (5) is arranged at the corner of the mixed phase discharge pipeline (103); The buffer (5) is L-shaped and consists of a horizontal pipe section (501) and a vertical pipe section (502). The horizontal pipe section (501) has equal-diameter holes (503). One end of the equal-diameter hole (503) has an inner diameter that gradually increases to form a gradually expanding portion (504). A baffle region (505) is formed at the connection of the gradually expanding portion (504) and the inner cavity of the vertical pipe section (502). An elastic flow-breaking plate (509) is arranged in the inner cavity of the vertical pipe section (502).

9. The treatment system for the slurry product after ebullated bed hydrogenation according to claim 8, characterized in that: A baffle plate (506) is inclined on the side wall of the inner cavity of the vertical pipe section (502). The free end of the baffle plate (506) extends beyond the gradually expanding portion (504) and into the baffle region (505), and a flow guiding region (507) for changing the flow direction of the gas-liquid mixed flow is formed between the baffle plate (506) and the gradually expanding portion (504).

10. The treatment system for the slurry product after ebullated bed hydrogenation according to claim 9, wherein: A baffle plate (5010) is arranged between the baffle plate (506) and the elastic flow-breaking plate (509). The baffle plate (5010) and the baffle plate (506) are on both sides of the axis of the vertical pipe section (502). The baffle plate (5010) is fixed on the side wall of the inner cavity of the vertical pipe section (502), and its free end is inclined towards the oncoming flow direction and forms an acute angle with the inner wall of the vertical pipe section (502) with the opening facing the oncoming flow direction.

11. A treatment system for the slurry product after ebullated bed hydrogenation according to claim 8, characterized in that: A conical liquid guiding cylinder (508) is arranged on the side wall of the inner cavity of the vertical pipe section (502). The large-diameter end of the conical liquid guiding cylinder (508) is fixed to the vertical pipe section (502), and the small-diameter end is open and faces the elastic flow-breaking plate (509).

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