Method and system for improving gasification rate of slag slurry product of fluidized bed

Abstract

The invention relates to a method and system for improving the gasification rate of a fluidized bed slag slurry product, belonging to the field of fluidized bed hydrogenation, oxygen is introduced into the slag slurry product in the form of microbubbles, oxygen microbubbles stably exist in the slag slurry product to form a mixed phase, then the mixed phase is atomized to form small liquid drops, and a water gas reaction is carried out to obtain a gas product; when the oxygen is mixed with the slag slurry product in the form of microbubbles, the slag slurry product is divided into two parts for hedging to form a hedging mixed flow area, and the oxygen microbubbles are mixed with the slag slurry product in the hedging mixed flow area; when the mixed phase is atomized, new oxygen flow is additionally introduced, the mixed phase and the oxygen flow are impacted to change the distribution form of microbubbles, and then the microbubbles are atomized and sprayed out for water gas reaction. According to the invention, the slag slurry product and the oxygen are mixed, atomized and subjected to the water gas reaction, so that the slag slurry product as waste is converted into a gas-phase product, effective utilization of the waste is realized, and the additional value of the product is improved.

Description

Technical Field

[0001] The present invention relates to the field of ebullated bed hydrogenation, and specifically to a method and system for improving the gasification rate of ebullated bed slurry products. Background Art

[0002] With the rapid development of the global economy, the rapidly growing demand for light and clean fuel oils, and the increasingly poor quality of crude oil with higher and higher heavy component contents, 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 treatment methods for residue oil generally include 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 metals and carbon residue of the raw materials; while the ebullated bed residue oil hydrogenation process has wide raw material adaptability 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 produced. 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 improving the gasification rate of ebullated bed slurry products. The treatment method and system mix the slurry products with oxygen, atomize them, and carry out the water-gas reaction, thereby converting the slurry products as waste into gas-phase products, achieving the effective utilization of waste and increasing the added value of the products.

[0006] The technical solution adopted by the present invention to achieve the above technical purpose is: a method for improving the gasification rate of ebullated bed slurry products, introducing oxygen into the slurry products of the ebullated bed in the form of microbubbles, and making the oxygen microbubbles stably exist in the slurry products to form a mixed phase. Then, the mixed phase is atomized into small droplets and undergoes the water-gas reaction to obtain gas products. When the oxygen is mixed with the slurry products in the form of microbubbles, the slurry products are divided into two parts for counterflow to form a counterflow mixing zone, and the oxygen is mixed with the slurry products in the form of microbubbles in the counterflow mixing zone; when the mixed phase is atomized, a new oxygen stream is additionally introduced, and the mixed phase and the oxygen stream are made to collide to change the distribution form of the microbubbles, and then atomized and ejected for the water-gas reaction.

[0007] As an optimized solution of the above method for increasing the gasification rate of fluidized bed slurry products, the reaction temperature of the water-gas reaction is 400 °C and the pressure is 1.5 MPa.

[0008] As another optimized solution of the above method for increasing the gasification rate of fluidized bed slurry products, when the mixed phase impacts with the oxygen flow, an included angle α is formed between the flow direction of the oxygen flow and the flow direction of the mixed phase, where 90° < α ≤ 180°.

[0009] As another optimized solution of the above method for increasing the gasification rate of fluidized bed slurry products, the mass of oxygen introduced in the form of microbubbles is 1-8% of the slurry products, the mass of the oxygen flow is 0.5-2% of the slurry products, and the flow rate of the oxygen flow is 80-200% of the flow rate of the mixed phase.

[0010] A system for increasing the gasification rate of fluidized bed slurry products includes a counter-jet mixing device for mixing slurry products and oxygen, a gasifier for carrying out the water-gas reaction, and an atomization mechanism for atomizing the mixed phase formed by the slurry products and oxygen and spraying it into the gasifier. Two counter-jet slurry pipelines are connected to the counter-jet mixing device, so that two streams of slurry products impact and enter the mixing cavity of the counter-jet mixing device from opposite directions. A discharge port is arranged on one side of the mixing cavity, and a microbubble generator communicated with an oxygen pipeline is arranged in the mixing cavity; the atomization mechanism is provided with a secondary oxygen supply pipeline, so that the oxygen flow impacts and mixes with the slurry products with microbubbles in the atomization mechanism, and then is atomized and sprayed into the gasifier.

[0011] As an optimized solution of the above system for increasing the gasification rate of fluidized bed slurry products, two slag inlets are symmetrically arranged on the mixing cavity, each slag inlet is communicated with a slurry pipeline, and the inner diameter of the slag inlet gradually decreases along the flow direction of the slurry products.

[0012] As another optimized solution of the above system for increasing the gasification rate of fluidized bed slurry products, the atomization mechanism has a cavity and a spray outlet. An inlet pipe is obliquely arranged on one side of the top of the cavity, and 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 obliquely upward and forms a gas guide area with an opening facing the oncoming flow direction with the cavity side wall. The secondary oxygen supply pipeline extends into the gas guide area near the spray outlet, and during the process of continuously discharging oxygen and spirally rising along the gas guide area, it impacts and mixes with the gas-liquid mixed flow entering from the inlet pipe in the cavity.

[0013] As another optimized solution of the above system for increasing the gasification rate of fluidized bed slurry products, the counter-jet mixing device is communicated with the atomization mechanism through an L-shaped mixed phase discharge pipeline, and a buffer is arranged 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 crushing baffle is arranged in the inner cavity of the vertical pipe section.

[0015] As another optimization scheme of the above system for improving the gasification rate of the fluidized bed slag slurry product, 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 beyond the gradually expanding part and then extends into the baffle area, and a diversion area for changing the flow direction of the gas-liquid mixed flow is formed between the baffle and the gradually expanding part.

[0016] As another optimization scheme of the above system for improving the gasification rate of the fluidized bed slag slurry product, a baffle plate is arranged between the baffle and the elastic crushing baffle, 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 optimization scheme of the above system for improving the gasification rate of the fluidized bed slag slurry product, 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 crushing baffle.

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

[0019] 1) After the slag slurry product is mixed with oxygen in the present invention, it is atomized and undergoes a water gas reaction, thereby converting the slag slurry product as waste into a gas-phase product, realizing the effective utilization of waste and increasing the added value of the product;

[0020] 2) Due to the extremely high viscosity of the slag slurry product, the atomization effect of the conventional atomization method is very poor. If the slag slurry product is directly fed into the gasifier without being fully atomized, it will lead to a decrease in the reaction efficiency with oxygen and a corresponding decrease in the gasification rate. On the basis of the existing "microbubble + liquid-phase mixing + atomization spraying", the present invention additionally introduces another oxygen stream, and makes the oxygen stream conduct countercurrent mixing with the slag slurry product mixed with microbubbles, so that during the process of atomization and spraying of the slag 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; through detection, the method of introducing oxygen twice in the present invention can increase the gasification rate by 1-5% compared with directly mixing all the oxygen in the form of microbubbles.

[0021] 3) 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 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 collides with the continuous oxygen flow supplemented by the secondary oxygen supply pipeline, 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) 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 inside the buffer of the present invention. Relying on the baffle plate to further change the flow state of part of the slurry product, 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 mixed phase; in addition, the presence of the conical liquid guide cylinder can guide the mixed phase 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 mixed phase, thereby improving the internal impact effect and promoting the secondary irregular distribution of microbubbles in the mixed phase;

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

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

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

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

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

[0028] Figure 5 isFigure 4 Schematic structural diagram of the middle buffer

[0029] Reference numerals: 1, counterflush mixing device; 101, slag slurry pipeline; 102, oxygen pipeline; 103, mixed-phase discharge pipeline; 104, slag inlet; 105, mixing chamber; 106, discharge port; 2, secondary oxygen supply pipeline; 3, gasifier; 4, atomization mechanism; 401, inlet pipe; 402, cavity; 403, spray outlet; 404, air guiding plate; 405, air guiding 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, guiding area; 508, conical liquid guide cylinder; 509, elastic broken flow plate; 5010, baffle plate Specific implementation manners

[0030] The technical solution of the present invention will be further elaborated in detail below in conjunction with specific embodiments. For parts not clarified 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 slag slurry product and oxygen, the parameters of the continuous oxygen flow charged into the secondary oxygen supply pipeline, and the structure of other auxiliary structures of the system for pressurizing the slag slurry product and oxygen, 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 improving the gasification rate of fluidized bed slurry products, which introduces oxygen into the slurry products of the fluidized bed in the form of microbubbles. Generally, pressure is applied to the slurry products so that oxygen microbubbles are introduced into them during the flow in the pipeline. Generally, an existing microbubble generator is used to form microbubbles of hydrogen and mix them with the slurry products. The mixing ratio can be adjusted according to the actual situation, and the oxygen microbubbles are stably present in the slurry products to form a mixed phase. The mass of oxygen introduced in the form of microbubbles is 1-8% of the slurry products, preferably 5%. Of course, other ratios can also be used, such as 1%, 1.5%, 2%, 3.5%, 4.2%, 5.6%, 6.5%, 7.4% and 8%, etc. After that, the mixed phase is atomized into small droplets and then the water-gas reaction is carried out. Atomization can be achieved by using existing atomization equipment. The equipment for carrying out the water-gas reaction is generally a gasifier. The conditions and parameters of the water-gas reaction are adjusted according to the actual situation to obtain gas products and solid residues that cannot be gasified. When the oxygen is mixed with the slurry products in the form of microbubbles, the slurry products are first divided into two parts and opposed to each other to form an opposed mixing flow zone. The oxygen is mixed with the slurry products in the form of microbubbles in the opposed mixing flow zone. In practice, two slurry pipes in opposite directions are simultaneously connected to a container, pressure is applied to the slurry products, so that the slurry products are ejected from both slurry pipes and opposed to each other in the container. The microbubble generator is in the container. At this time, due to the opposition, the slurry products undergo a sharp turbulence and are mixed with the microbubbles at this time, which can achieve a better mixing effect. When the mixed phase is atomized, a new oxygen stream is additionally introduced. The mass of the oxygen stream is 0.5-2% of the slurry products, preferably 1%. Of course, other ratios can also be used, such as 0.5%, 1.2%, 1.5%, 1.6%, 1.7%, 1.8% and 2%, etc. And the flow rate of the oxygen stream is 80-200% of the flow rate of the mixed phase, preferably 100-150%. In practice, the oxygen stream is introduced into the atomizing nozzle through a separate pipeline, and the mixed phase and the oxygen stream impact each other in the atomizing nozzle to change the distribution form of the microbubbles, and then atomize and eject to carry out the water-gas reaction. When the mixed phase and the oxygen stream impact each other, an included angle α is formed between the flow direction of the oxygen stream and the flow direction of the mixed phase, 90° < α ≤ 180°, and the angle of α is preferably 160-180°.

[0033] In this embodiment, the reaction temperature of the water-gas reaction is 400 °C and the pressure is 1.5 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] A system for improving the gasification rate of fluidized bed slurry products, such as Figure 1As shown in the figure, it includes an impact mixing device 1 for mixing the slurry product with oxygen, a gasifier 3 for carrying out the water-gas reaction, and an atomization mechanism 4 for atomizing the mixed phase formed by the slurry product and oxygen and spraying it into the gasifier 3. In this embodiment, the gasifier 3 and the atomization mechanism 4 can directly adopt commercially available gasifiers and atomization nozzles, so their structures and models will not be elaborated; as Figure 2 As shown in the figure, two opposing slurry pipelines 101 are connected to the impact mixing device 1. The impact mixing device 1 is a tubular member with openings at both ends in a vertical state. The two slurry pipelines 101 are respectively located at the top and the bottom. A mixing chamber 105 is formed inside the tubular member, so that two slurry products enter the mixing chamber 105 of the impact mixing device 1 from opposite directions (i.e., one from top to bottom), and collide and mix in the mixing chamber 105. A discharge port 106 is provided at the middle position on one side of the mixing chamber 105. A microbubble generator communicating with the oxygen pipeline 102 is provided in the mixing chamber 105. In this embodiment, a commercially available microbubble generator can be selected for the microbubble generator. Its purpose is to form microbubbles of oxygen to mix with the slurry product. The size of the microbubbles is preferably below 30 microns, so that oxygen can exist stably in the slurry product in the form of microbubbles as much as possible. The installation position of the microbubble generator is generally at the impact point when the two slurry products oppose each other; the atomization mechanism 4 is provided with a secondary oxygen supply pipeline 2, and oxygen is continuously introduced into the atomization mechanism 4 through the secondary oxygen supply pipeline 2, so that the oxygen flow and the slurry product with microbubbles impact and mix in the atomization mechanism 4, and then are atomized and sprayed into the gasifier 3, and the water-gas reaction occurs under certain conditions to generate gas-phase products.

[0037] In this embodiment, two slag inlets 104 are symmetrically arranged on the mixing chamber 105. These two slag inlets 104 are symmetrically arranged one above the other. Each slag inlet 104 is connected to a slurry pipeline 101. The inner diameter of the slag inlet 104 gradually decreases along the flow direction of the slurry product. The shape of the slag inlet 104 is generally conical, and the ratio of the large diameter end to the small diameter end of the slag inlet 104 is generally 10 - 20:1. Its length accounts for 10 - 20% of the total length of the impact mixing device 1. The inner diameter of the small diameter end of the slag inlet 104 is generally 3 - 8 mm; the discharge port 106 is preferably conical, and its diameter gradually decreases along the flow direction of the mixed phase, and a discharge pipe is connected to the small diameter end; the unique design of the slag inlet 104 enables the slurry to produce a jet dispersion effect when entering the mixing chamber 105 through the slag inlet 104 because the space suddenly decreases and then expands, and then fully mixes with the oxygen microbubbles in the mixing chamber 105; and the design of the discharge port 106 makes it difficult for the slurry to be quickly discharged, thus generating a pressure-increasing effect in the mixing chamber 105, promoting the full mixing of the oxygen microbubbles and the slurry and stably existing.

[0038] Example 3

[0039] This embodiment is an improved solution for the atomization mechanism 4 based on Embodiment 2. Its main structure is the same as that of Embodiment 2. The improvement lies in that the atomization mechanism 4 can adopt an existing atomizing nozzle, but only a secondary oxygen supply pipeline 2 needs to be added to the atomizing nozzle. However, the following structure is preferably adopted, as Figure 3 shown, that is, the atomization mechanism 4 has a cavity 402 and a jet outlet 403. An inlet pipe 401 is inclinedly arranged on one side of the top of the cavity 402. The inlet pipe 401 is communicated with the mixed-phase discharge pipeline 103. The inlet pipe 401 is inclinedly arranged, generally forming an angle of not less than 50° with the vertical direction, preferably 70 - 80°. Most preferably, the slurry product is injected along the tangent direction of the cavity 402. A spiral air guide plate 404 is arranged around the inner side wall of the cavity 402. One side edge of the air guide plate 404 is fixed to the inner wall of the cavity 402, and the other side is inclined upward, forming an air guide area 405 with an opening facing the oncoming flow direction with the cavity side wall. In practice, the air guide plate 404 is a spiral plate. Looking from the horizontal direction, the projection of the air guide 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 air guide area 405 is actually a spiral groove, and the depth of the groove is generally greater than the air inlet of the secondary oxygen supply pipeline 2 introducing the continuous-phase gas. In practice, the secondary oxygen supply pipeline 2 is communicated with an inclined hole opened on the inner side wall of the cavity 402. The diameter of the inclined hole is less than half of the groove depth. The secondary oxygen supply pipeline 2 extends into the air guide area 405 near the jet outlet 403. The secondary oxygen supply pipeline 2 is at one end of the air guide area 405 near the jet outlet 403. The axial direction of the secondary oxygen supply pipeline 2 can be perpendicular to the axial direction of the cavity 402, or can form a certain acute or obtuse angle with the axial direction of the cavity 402. Preferably, the secondary oxygen supply pipeline 2 is perpendicular to the axis of the cavity 402, and the continuous-phase gas is injected 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 guide plate 404, so that the gas moves along the spiral air guide plate 404 in the direction away from the jet outlet 403, and during the process of continuously discharging oxygen and spirally rising along the air guide area 405, it impacts and mixes with the gas-liquid mixed flow entering from the inlet pipe 401 in the cavity 402.

[0040] 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 spray outlet 403 is located at the bottom tip of the conical area. The air guiding plate 404 is distributed on the inner side wall of the cylindrical area. The two ends of the air guiding plate 404 do not extend beyond the upper and lower end faces of the cylindrical area. The secondary oxygen supply pipeline 2 is located at a position close to the spray outlet 403 in the air guiding area 405 and is within the included angle formed by the air guiding plate 404 and the side wall of the cylindrical area.

[0041] Embodiment 4

[0042] This embodiment is another improved solution based on Embodiment 2. Its main structure is the same as that of Embodiment 2. The improvement lies in: as Figure 4 shown, the counterflush mixing 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 atomization nozzle, but only a secondary oxygen supply pipeline 2 needs to be added to the atomization 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;

[0043] The buffer 5 is an L-shaped hollow tubular structure, which is formed by integrally connecting the end of a horizontal pipe section 501 and a vertical pipe section 502. The outer diameters of the horizontal pipe section 501 and the vertical pipe section 502 are generally the same, and their axes are perpendicular to each other. The horizontal pipe section 501 has an equal-diameter hole 503, and the equal-diameter hole 503 is 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 part 504. In fact, the equal-diameter hole 503 and the gradually expanding part 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 part 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 fragmentation plate 509 is provided in the inner cavity of the vertical pipe section 502, and the elastic fragmentation plate 509 does not affect the outflow of the mixed phase.

[0044] In this embodiment, the elastic fragmentation flow plate 509 can be a conventional metal plate, 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 fragmentation flow 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 inner cavity shape of the vertical pipe section 502, and the two are coaxial. 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.

[0045] In this embodiment, a baffle plate 506 is inclinedly arranged on the side wall of the inner cavity of the vertical pipe section 502. 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 into the baffle area 505 after exceeding the extension line of the side wall of the gradually expanding part 504. 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 close 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 attached to the side wall of the inner cavity of the vertical pipe section 502, and 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 inner cavity of the vertical pipe section 502, and forms a diversion area 507 for changing the flow direction of the gas-liquid mixed flow with the gradually expanding part 504;

[0046] In addition, in this embodiment, a baffle plate 5010 can also be arranged between the baffle plate 506 and the elastic fragmentation flow plate 509, as Figure 5As shown, the baffle 5010 is preferably made of an erosion-resistant alloy material. It forms an angle of 20 - 60° with the inner wall of the vertical pipe section 502. The baffle 5010 and the flow baffle 506 are located on both sides of the axial direction of the vertical pipe section 502. The projections of the free ends of the baffle 5010 and the flow baffle 506 in the radial direction of the vertical pipe section 502 do not touch. The baffle 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. The so-called oncoming flow direction refers to the flow direction of the mixed phase, 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 mixed phase forms a backflow within this acute angle. In practice, the baffle 5010 is actually an arc-shaped plate, its arc-shaped side is arranged against the side wall of the inner cavity of the vertical pipe section 502, and 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;

[0047] In addition, in this embodiment, a conical liquid guide cylinder 508 can also be provided 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 openings at both ends 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 baffle 509, so as to guide the gas-liquid mixed phase to impact on the elastic fragmentation baffle 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 baffle 509.

[0048] In order to verify the specific effects of the present invention, the following comparative experiments were carried out:

[0049] Experimental content:

[0050] The properties of the selected heavy oil are as follows: density is 0.978 g / cm 3 (20 °C), kinematic viscosity is 3396 mm 2 / s (80 °C), 859.6 mm 2 / s (100 °C), the residual carbon content is 3.6%, the H content is 12.53%, and the S content is 0.22%;

[0051] The heavy oil and hydrogen were sent into the fluidized bed for fluidized bed hydrotreating reaction. The conditions of the hydrotreating reaction were: temperature 400 °C, hydrogen partial pressure 15 MPa, total volume space velocity 0.15 h -1 , and finally a viscous slurry product was obtained as the experimental raw material;

[0052] Comparative Example 1

[0053] A certain amount of experimental raw materials was directly fed into the gasifier, and the water-gas reaction was directly carried out under the conditions of a reaction temperature of 400 °C and a pressure of 1.5 MPa to obtain a gaseous product and a solid residue. The mass of the remaining solid residue was weighed, and the gasification rate was calculated to be 69.26% according to the following formula;

[0054] Gasification rate = 100% - (mass of solid residue / mass of experimental raw materials * 100%).

[0055] Comparative Example 2

[0056] The experimental raw materials were mixed with 5% of their weight of oxygen and then atomized through an atomizing nozzle and fed into the gasifier. The diameter of the spray holes in the atomizing nozzle was 0.8 mm. After being mixed with oxygen, the experimental raw materials were atomized and sprayed into the gasifier at a pressure of 3 MPa. Under the conditions of a reaction temperature of 400 °C and a pressure of 1.5 MPa, the water-gas reaction was directly carried out to obtain a gaseous product and a solid residue. The mass of the remaining solid residue was weighed, and the gasification rate was calculated to be 71.53% according to the formula in Comparative Example 1.

[0057] Comparative Example 3

[0058] The experimental raw materials were mixed with 5% of their mass of oxygen. This part of oxygen was used to form a microbubble stream with a size not exceeding 30 microns by an existing microbubble generator and was introduced into the experimental raw materials to form a mixed phase. The mixed phase was sprayed into the gasifier through the atomizing nozzle in Comparative Example 2. Synchronously, an oxygen stream of 1% of the mass of the experimental raw materials was introduced into the atomizing nozzle, and the flow direction of the oxygen stream formed an angle of 160° with the flow direction of the slurry in the atomizing nozzle;

[0059] Under the conditions of a reaction temperature of 400 °C and a pressure of 1.5 MPa, the water-gas reaction was carried out to obtain a gaseous product and a solid residue. The mass of the remaining solid residue was weighed, and the gasification rate was calculated to be 74.89% according to the formula in Comparative Example 1.

[0060] Comparative Example 4

[0061] On the basis of Comparative Example 3, the mixed phase formed by mixing the experimental raw materials with microbubbles was first passed through the buffer 5 in Example 5 and then sprayed into the gasifier through the atomizing nozzle in Comparative Example 2. Synchronously, an oxygen stream of 1% of the mass of the experimental raw materials was introduced into the atomizing nozzle, and the flow direction of the oxygen stream formed an angle of 160° with the flow direction of the slurry in the atomizing nozzle;

[0062] Under the conditions of a reaction temperature of 400 °C and a pressure of 1.5 MPa, the water-gas reaction was carried out to obtain a gaseous product and a solid residue. The mass of the remaining solid residue was weighed, and the gasification rate was calculated to be 76.35% according to the formula in Comparative Example 1.

[0063] Experimental conclusion:

[0064] It can be seen from the comparison between Comparative Example 1 and Comparative Example 2 that the gasification rate will increase to a certain extent when the slag slurry product is mixed with oxygen and then gasified. That is to say, introducing oxygen helps to increase the gasification rate;

[0065] It can be seen from the comparison between Comparative Example 2 and Comparative Example 3 that for the same mass of oxygen, first mixing it with the slag slurry in the form of microbubbles and then introducing the remaining oxygen during the atomizing spray process can significantly increase the gasification rate, indicating that this two-stage oxygen introduction method can effectively improve the gasification rate;

[0066] It can be seen from the comparison between Comparative Example 3 and Comparative Example 4 that after additionally setting up the buffer 5 before the atomizing spray, the gasification rate is further increased, indicating that the setting of the buffer 5 can effectively improve the gasification rate of the slag slurry product.

Claims

1. A method for improving the gasification rate of the slurry product in a fluidized bed, which comprises introducing oxygen into the slurry product of the fluidized bed in the form of microbubbles, and enabling the oxygen microbubbles to stably exist in the slurry product to form a mixed phase, and then atomizing the mixed phase to form small droplets and performing a water-gas reaction to obtain a gas product, characterized in that: When the oxygen is mixed with the slurry product in the form of microbubbles, the slurry product is divided into two parts for counter-jetting to form a counter-jet mixing zone, and the oxygen is mixed with the slurry product in the form of microbubbles in the counter-jet mixing zone; when the mixed phase is atomized, a new oxygen stream is additionally introduced, and the mixed phase is impacted by the oxygen stream to change the distribution pattern of the microbubbles, and then atomized and ejected for the water gas reaction.

2. A method for improving the gasification rate of fluidized bed slag slurry products according to claim 1, characterized in that: The reaction temperature of the water gas reaction is 400 °C and the pressure is 1.5 MPa.

3. A method for improving the gasification rate of the fluidized bed slag slurry product according to claim 1, characterized in that: When the mixed phase is impacted by the oxygen stream, an included angle α is formed between the flow direction of the oxygen stream and the flow direction of the mixed phase, and 90° < α ≤ 180°.

4. A method for improving the gasification rate of the fluidized bed slag slurry product according to claim 1, characterized in that: The mass of the oxygen introduced in the form of microbubbles is 1-8% of the slurry product, the mass of the oxygen stream is 0.5-2% of the slurry product, and the flow rate of the oxygen stream is 80-200% of the flow rate of the mixed phase.

5. A system for improving the gasification rate of fluidized bed slag slurry products, comprising a counter-jet mixing device (1) for mixing the slag slurry products with oxygen, a gasifier (3) for carrying out the water gas reaction, and an atomization mechanism (4) for atomizing the mixed phase formed by the slag slurry products and oxygen and injecting it into the gasifier (3), characterized in that: Two counter-jet slurry pipelines (101) are connected to the counter-jet mixing device (1), so that two slurry products are impacted and enter the mixing chamber (105) of the counter-jet mixing device (1) from opposite directions. A discharge port (106) is arranged on one side of the mixing chamber (105), and a microbubble generator communicated with the oxygen pipeline (102) is arranged in the mixing chamber (105); a secondary oxygen supply pipeline (2) is arranged on the atomization mechanism (4) so that the oxygen stream and the slurry product with microbubbles are impacted and mixed in the atomization mechanism (4), and then atomized and ejected into the gasifier (3).

6. The system for improving the gasification rate of the fluidized bed slag slurry product according to claim 5, characterized in that: Two slag inlets (104) are symmetrically arranged on the mixing chamber (105), each slag inlet (104) is communicated with a slurry pipeline (101), and the inner diameter of the slag inlet (104) gradually decreases along the flow direction of the slurry product.

7. A system for improving the gasification rate of fluidized bed slag slurry products according to claim 5, characterized in that: The atomization mechanism (4) has a cavity (402) and a spray outlet (403). An inlet pipe (401) is inclinedly arranged on one side of the top of the cavity (402). A spiral air guide plate (404) is arranged around the inner side wall of the cavity (402). One side edge of the air guide plate (404) is fixed to the inner wall of the cavity (402), and the other side is inclined upward and forms a gas guide area (405) with an opening facing the oncoming flow direction with the cavity side wall. The secondary oxygen supply pipeline (2) extends into the gas guide area (405) at a position close to the spray outlet (403), and during the process that the oxygen continuously discharged along the spiral upward in the gas guide area (405), it impacts and mixes with the gas-liquid mixed flow entering from the inlet pipe (401) in the cavity (402).

8. A system for improving the gasification rate of fluidized bed slag slurry products according to claim 5, characterized in that: The counter-jet mixing 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 is composed of a horizontal pipe section (501) and a vertical pipe section (502). Equal-diameter holes (503) are arranged in the horizontal pipe section (501). One end of the equal-diameter hole (503) has an inner diameter gradually increasing to form a gradually expanding part (504), and a flow-through area (505) is formed at the connection of the gradually expanding part (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. A system for improving the gasification rate of fluidized bed slag slurry products according to claim 8, characterized in that: On the side wall of the inner cavity of the vertical pipe section (502), a baffle plate (506) is inclined. The free end of the baffle plate (506) extends beyond the gradually expanding part (504) and then into the flow deflection area (505), and a diversion area (507) for changing the flow direction of the gas-liquid mixed flow is formed between the baffle plate (506) and the gradually expanding part (504).

10. A system for improving the gasification rate of fluidized bed slag slurry products according to claim 9, characterized in that: A baffle plate (5010) is arranged between the baffle plate (506) and the elastic flow-breaking plate (509), 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 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 an acute angle with an opening facing the oncoming flow direction is formed between the baffle plate (5010) and the inner wall of the vertical pipe section (502).

11. A system for improving the gasification rate of fluidized bed slag slurry products according to claim 8, characterized in that: A conical liquid guide 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 guide 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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