Raw oil multi-stage atomizing nozzle structure for heavy oil catalytic cracking

Abstract

The utility model discloses a raw oil multistage atomizing nozzle structure for heavy oil catalytic cracking, which comprises a spray pipe, an outer cavity, an inner cavity and a spray head, the spray pipe is sleeved in the spray head, a plurality of spray holes distributed at intervals are arranged at one end of a spray head body far away from the spray pipe, and a first steam inlet pipe is arranged at one end of the spray pipe far away from the spray head. A first cavity channel, a second cavity channel, a third cavity channel and a nozzle are sequentially arranged in the spray pipe from left to right, and the first steam inlet pipe is communicated with the first cavity channel; a heavy oil inlet pipe and a third steam inlet pipe are arranged on the side wall of the spray pipe, a second steam inlet pipe is arranged in the heavy oil inlet pipe, an outer cavity is formed in the heavy oil inlet pipe, a flow guide cone is arranged at the tail end of the second steam inlet pipe, and bubble holes are formed in the pipe wall, close to the flow guide cone, of the second steam inlet pipe. An inner cavity of the second steam inlet pipe is communicated with the outer cavity through the bubble holes, and the heavy oil inlet pipe is communicated with the first cavity channel.

Description

Technical Field

[0001] The utility model relates to an atomizing nozzle for catalytic cracking feed in the field of petroleum refining, in particular to a multi-stage atomizing nozzle structure for raw oil in heavy oil catalytic cracking. Background Art

[0002] Catalytic cracking is a petroleum refining process that uses heat and a catalyst to crack heavy oil, converting it into cracked gas, gasoline, and diesel. Compared to thermal cracking, it offers higher yields of light oil, higher octane numbers for gasoline, better diesel stability, and produces olefin-rich liquefied petroleum gas as a by-product.

[0003] The heavy oil catalytic cracking process is a secondary process in petroleum refining. Atomizing nozzles are used in the catalytic cracking of heavy oil. The feed atomizing nozzle is an important equipment in the heavy oil catalytic cracking unit in the petroleum refining field. Its function is to: under the action of atomizing steam, break up and atomize the raw oil into a large number of fine droplets, and then spray the raw oil droplets into the catalytic cracking riser reactor to mix and react with the catalyst in the riser reactor;

[0004] However, the atomization particle size of the existing heavy oil feed atomizing nozzle is expected to be further reduced; in addition, the atomizing steam and the raw oil affect each other in the inlet area of ​​the nozzle, and even when the pressure of the atomizing steam (or raw oil) fluctuates, the raw oil (or atomizing steam) cannot be introduced into the nozzle. Utility Model Content

[0005] The technical problem to be solved by the utility model is to overcome the defects of the above-mentioned technology and provide a multi-stage atomizing nozzle structure for raw oil of heavy oil catalytic cracking.

[0006] To solve the above technical problems, the technical solution provided by the present invention is a multi-stage atomizing nozzle structure for raw oil for catalytic cracking of heavy oil, comprising a nozzle, an outer cavity, an inner cavity, and a nozzle. The nozzle is sleeved inside the nozzle, and a plurality of spray holes distributed at intervals are opened at the end of the nozzle body away from the nozzle. A first steam inlet pipe is provided at the end of the nozzle away from the nozzle. A first cavity, a second cavity, a third cavity, and a nozzle are sequentially provided in the nozzle from left to right. The first steam inlet pipe is connected to the first cavity.

[0007] A heavy oil inlet pipe and a No. 3 steam inlet pipe are provided on the side wall of the nozzle. A No. 2 steam inlet pipe is provided inside the heavy oil inlet pipe. An outer cavity is provided inside the heavy oil inlet pipe. A guide cone is provided at the end of the No. 2 steam inlet pipe. Bubble holes are provided on the wall of the No. 2 steam inlet pipe near the guide cone. The inner cavity of the No. 2 steam inlet pipe is connected to the outer cavity through the bubble hole, and the heavy oil inlet pipe is connected to the first cavity.

[0008] Furthermore, the spray holes are distributed in a fan shape along the outer surface of the nozzle.

[0009] Furthermore, the No. 3 steam inlet pipe is connected to the first cavity.

[0010] Furthermore, the longitudinal section of the spray hole is fan-shaped.

[0011] The advantages of the present invention over the prior art are as follows: the present invention provides a multi-stage atomizing nozzle structure for crude oil, wherein a first cavity, a second cavity, a third cavity, and a nozzle are sequentially arranged from left to right in the nozzle, and a No. 1 steam inlet pipe, a heavy oil inlet pipe, a No. 2 steam inlet pipe, and a No. 3 steam inlet pipe are arranged on the nozzle. The above structure integrates the excellent features of a target nozzle and a throat nozzle. Due to the principle that droplets are generated by the rapid expansion of the flow channel in the nozzle, the sudden change in the pressure difference between the inside and outside of the bubble, and the rapid breakup of the bubble, the atomized particle size of the heavy oil after multiple breakages is further reduced, the gas flow rate and the velocity difference between the gas and liquid phases are increased as much as possible, and the atomization efficiency is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 The utility model is a structural schematic diagram of a multi-stage atomizing nozzle structure of raw oil for heavy oil catalytic cracking.

[0013] As shown in the figure: 1. Nozzle, 2. No. 1 steam inlet pipe, 3. No. 2 steam inlet pipe, 4. Heavy oil inlet pipe, 5. Outer cavity, 6. Inner cavity, 7. Bubble hole, 8. Guide cone, 9. No. 3 steam inlet pipe, 10. First cavity, 11. Second cavity, 12. Third cavity, 13. Nozzle, 14. Nozzle, 15. Spray hole. DETAILED DESCRIPTION

[0014] The following is a further detailed description of the multi-stage atomizing nozzle structure for heavy oil catalytic cracking of the present invention in conjunction with the accompanying drawings.

[0015] With reference to the accompanying drawings, a multi-stage atomizing nozzle structure for feedstock oil for heavy oil catalytic cracking includes a nozzle 1, an outer cavity 5, an inner cavity 6, and a nozzle 14. The nozzle 1 is sleeved inside the nozzle 14. The nozzle 14 body is provided with a plurality of spaced-apart spray holes 15 at one end away from the nozzle 1. A first steam inlet pipe 2 is provided at the end of the nozzle 1 away from the nozzle 14. A first cavity 10, a second cavity 11, a third cavity 12, and a nozzle 13 are provided in the nozzle 1 from left to right. The first steam inlet pipe 2 is connected to the first cavity 10.

[0016] A heavy oil inlet pipe 4 and a No. 3 steam inlet pipe 9 are provided on the side wall of the nozzle 1. A No. 2 steam inlet pipe 3 is provided inside the heavy oil inlet pipe 4. An outer cavity 5 is provided inside the heavy oil inlet pipe 4. A guide cone 8 is provided at the end of the No. 2 steam inlet pipe 3. A bubble hole 7 is provided on the wall of the No. 2 steam inlet pipe 3 near the guide cone 8. The inner cavity 6 of the No. 2 steam inlet pipe 3 is connected to the outer cavity 5 through the bubble hole 7, and the heavy oil inlet pipe 4 is connected to the first cavity 10.

[0017] As a preferred implementation scheme of this embodiment, the spray holes 15 are distributed in a fan shape along the outer surface of the spray head 14.

[0018] As a preferred implementation scheme of this embodiment, the No. 3 steam inlet pipe 9 is connected to the first cavity 10.

[0019] As a preferred implementation scheme of this embodiment, the longitudinal section of the spray hole 15 is fan-shaped.

[0020] During the specific implementation of the present invention, the No. 1 steam inlet pipe 2 is a high-pressure steam inlet pipe. After steam is introduced into the No. 2 steam inlet pipe 3, the steam radially flows out from the inner cavity 6 to the outer cavity 5 through the bubble hole 7, and mixes with the heavy oil in the heavy oil inlet pipe 4 to generate a bubbly flow. After the bubbly flow enters the first cavity 10, it is impacted by the high-pressure steam in the No. 1 steam inlet pipe 2 to form an initial mixture. The initial mixture advances along the first cavity 10, the second cavity 11, and the third cavity 12. Due to the different diameters of the first cavity 10, the second cavity 11, and the third cavity 12, the gas-liquid velocity difference becomes larger, and the initial mixture is further torn and broken again. It is then ejected through the nozzle 13, enters the nozzle 14, and finally ejected through the nozzle 15.

[0021] The spray holes 15 are distributed in a fan shape along the outer surface of the nozzle 14, and the longitudinal section of the spray holes 15 is fan-shaped, which can avoid dead angles inside the nozzle 14 body and prevent damage to the pipeline caused by vibration caused by operation fluctuations during operation;

[0022] This device integrates the excellent features of target nozzles and throat nozzles. Due to the principle that the flow channel in the nozzle expands rapidly, the pressure difference between the inside and outside of the bubble changes suddenly, and the bubble breaks quickly to produce droplets, the atomized particle size of the heavy oil after multiple breakages can be further reduced. It also maximizes the gas flow rate and the velocity difference between the gas and liquid phases, thereby improving the atomization efficiency.

[0023] The above description of the present invention and its embodiments is non-limiting. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if a person skilled in the art is inspired by the above, and does not deviate from the purpose of the present invention, without inventive design, a structure and embodiment similar to the technical solution should fall within the scope of protection of the present invention.

Claims

1. A multi-stage atomizing nozzle structure for raw oil of heavy oil catalytic cracking, characterized in that: The invention comprises a nozzle (1), an outer cavity (5), an inner cavity (6), and a nozzle (14); the nozzle (1) is sleeved inside the nozzle (14); a plurality of spray holes (15) distributed at intervals are provided at one end of the nozzle (14) body away from the nozzle (1); a first steam inlet pipe (2) is provided at one end of the nozzle (1) away from the nozzle (14); a first cavity (10), a second cavity (11), a third cavity (12), and a nozzle (13) are provided in the nozzle (1) from left to right in sequence; and the first steam inlet pipe (2) is connected to the first cavity (10); A heavy oil inlet pipe (4) and a third steam inlet pipe (9) are provided on the side wall of the nozzle (1); a second steam inlet pipe (3) is provided inside the heavy oil inlet pipe (4); an outer cavity (5) is provided inside the heavy oil inlet pipe (4); a guide cone (8) is provided at the end of the second steam inlet pipe (3); a bubble hole (7) is provided on the wall of the second steam inlet pipe (3) near the guide cone (8); the inner cavity (6) of the second steam inlet pipe (3) is connected to the outer cavity (5) through the bubble hole (7); and the heavy oil inlet pipe (4) is connected to the first cavity (10).

2. The multi-stage atomizing nozzle structure for raw oil of heavy oil catalytic cracking according to claim 1 is characterized in that: The spray holes (15) are distributed in a fan shape along the outer surface of the spray head (14).

3. The multi-stage atomizing nozzle structure for raw oil of heavy oil catalytic cracking according to claim 1 is characterized in that: The third steam inlet pipe (9) is in communication with the first cavity (10).

4. The multi-stage atomizing nozzle structure for raw oil of heavy oil catalytic cracking according to claim 1 is characterized in that: The longitudinal section of the spray hole (15) is fan-shaped.

Images