CN2754736Y

CN2754736Y - Atomizing feeding nozzle

Info

Publication number: CN2754736Y
Application number: CN 200420116132
Authority: CN
Inventors: 张荣克; 李进贤; 龚宏; 陈步学; 张蓉生; 杨启业; 闫涛; 余龙红; 吴雷; 濮思康; 张必强; 王俊彪
Original assignee: Sinopec Engineering Inc; Northwestern Polytechnical University; China Petrochemical Corp
Current assignee: Sinopec Engineering Inc; Northwestern Polytechnical University
Priority date: 2004-12-03
Filing date: 2004-12-03
Publication date: 2006-02-01
Anticipated expiration: 2014-12-03

Abstract

The utility model relates to an atomizing feeding nozzle which is a feeding nozzle suitable for catalytic cracking devices of heavy oil or/ and residual oil. The utility model comprises a primary air inlet, an oil inlet, a mixing chamber, an atomizing chamber, a swirler, an accelerating section, an injection pipe, a spray head and an outer nozzle; simultaneously a secondary air inlet chamber structure is used; the secondary air inlet chamber structure is composed of a secondary air inlet and a secondary air inlet chamber provided with an annular distribution pore plate; a swirler is welded between the mixing chamber and the atomizing chamber; not only is the periphery of the swirler provided with swirling flow grooves, but also the central part is provided with conical holes or arcuate orifices. Because the structure is used, the utility model has the characteristics of stable atomizing performance, favorable atomizing effect, strong operational versatility, low pressure drop, little energy consumption, wear resistance and capability of running for a long period.

Description

A kind of atomized feed nozzle

Technical field

The utility model belongs to petrochemical equipment, more particularly, is a kind ofly to be applicable to heavy oil or/and the catalytic cracking unit feed nozzle of residual oil.

Background technology

Along with the RFCC technology rapid development, people wish therefrom to obtain higher economic benefit.As adopt the heaviness raw material, make its raw material sources more extensive.The RFCC raw material develops into full atmospheric residue by the full distillate oil in past, further develops the RFCC of mixing refining certain proportion decompression residuum.Some are difficult to the low grade oils of cracking, as wax tailings also as the raw material of RFCC.

Heavy oil is or/and RFCC, because the ratio of raw material is great, viscosity is big, tenor and green coke amount height, cracking reaction is very difficult, often excessive owing to reaction system green coke amount, and cause the regenerative system carbon-burning load excessive, regeneration temperature is difficult to steadily and control; Or serious because of coking, and make the device can't long period production.Solve the problems referred to above that the RFCC technology exists, except improving technology and improving the performance of catalyst, the structure that improves equipment also is an importance.Wherein, designing a kind of new and effective atomized feed nozzle also is one of important techniques.Well behaved atomized feed nozzle not only can reduce the green coke amount and the dry gas amount of course of reaction, improves the productive rate of light oil or liquefied gas, and can prevent the coking of reaction system, is the key equipment of assurance device long-term operation.

All there is following some problem in situation from the use of present catalytic cracking unit feed nozzle in varying degrees: the one, the nozzle performance instability, atomizing effect is not ideal enough, and is relatively poor to the adaptability of operation, the time and have coking phenomenon to take place; The 2nd, jet velocity is too high, and catalyst is had fragmentation, causes slurry oil solids content and balance catalyst fines content bigger than normal; The 3rd, the nozzle wear phenomenon that has is serious, and performance just descends after coming into operation 1 year, is difficult to adapt to long-term operation.In addition, catalytic cracking is one of bigger device of petrochemical plant steam consumption quantity, in order to reduce energy consumption, wish to replace the required steam of nozzle atomization whole or in part, and existing nozzle arrangements also is difficult to adapt to this operating mode by " dry gas " that catalytic cracking unit self produces.

By retrieval, with the immediate technology of the utility model be the Chinese utility model patent ZL98233035.9 that the applicant authorized on January 5th, 2000, and the utility model is just to the further improvement of above-mentioned patent, the characteristics of ZL98233035.9 are that gas, liquid two-phase all enter mixing chamber, quicken through the cyclone rotation, smashed by air-flow behind the liquid generate film, realize primary atomization, have atomization preferably.Its shortcoming is because gas-liquid two-phase proportion difference flat stream, liquid layer skewness occur sometimes by the shower nozzle ejection behind cyclone, occurs thick liquid grain splash phenomena on the liquid layer edge.

Summary of the invention

A kind of new and effective atomized feed nozzle of the utility model is for overcoming above-mentioned shortcoming Development and design, and it is good to require it to have atomization, and strong to the adaptability of operation, pressure drop is low, energy consumption is little, and is wear-resisting, the characteristics of energy long-term operation.

For achieving the above object, the technical solution adopted in the utility model is: this catalysis feed nozzle comprises air inlet, oil inlet, mixing chamber, spray chamber, cyclone, accelerating sections, playpipe, shower nozzle and outer spout one time, adopt twice air inlet and secondary air inlet cell structure, this structure comprises secondary air inlet mouth and secondary air inlet chamber.The outer wall of mixing chamber and spray chamber is close in the secondary air inlet chamber, is the straight tube of an annular; Simultaneously be provided with distribution orifice in the secondary air inlet chamber, distribution orifice is arranged along the circumferential annular of spray chamber; Welding cyclone between mixing chamber and spray chamber, cyclone not only has the eddy flow groove at periphery, and at central part bellmouth or arcuate socket is arranged.

When the central part of cyclone was bellmouth, the front portion was a tapered conical, and the centre is a cylindrical shape, and the rear portion is the flaring taper; When the central part of cyclone was arcuate socket, the front portion was a convergent shape, and the rear portion is the diffusion arc.

Owing to adopted above-mentioned twice air inlet and secondary air inlet cell structure, and the secondary air inlet chamber has distribution orifice, by the effect of secondary air inlet chamber and distribution orifice, both air-flow evenly can be distributed along annular space, air-flow can be quickened again.It is very high that gas ejects speed through aperture, utilizes the speed difference of gas and fluid further oil film to be torn up.Simultaneously, secondary gas flows along the injection pipe wall, has destroyed the viscous flow of the elaioleucite behind the primary atomization at playpipe tube wall place, thereby eliminates the phenomenon that aggregates into big liquid grain once more, realizes the secondary-atomizing of feedstock oil.Because adopt the cyclone of said structure, different with the cyclone that peripheral eddy flow groove is only arranged, the bellmouth of central part or arcuate socket can make the liquid layer distribution uniform of ejection.Reduce jet velocity simultaneously, help the even contact of catalyst and elaioleucite, help the carrying out of catalytic reaction, guarantee the good operation of catalytic cracking unit.

Below in conjunction with the drawings and specific embodiments the utility model is done detailed description further

Description of drawings

The structural representation of accompanying drawing 1 the utility model high-efficient atomizing feed nozzle

Accompanying drawing 2 cyclone central parts are the structural representation of bellmouth

Accompanying drawing 3 cyclone central parts are the structural representation of arcuate socket

The specific embodiment

As shown in Figure 1, a kind of new and effective atomized feed nozzle of the utility model comprises air inlet 1, oil inlet 2, mixing chamber 3, spray chamber 7, cyclone 4, accelerating sections 12, playpipe 9, shower nozzle 10 and outer spout 11 one time, adopt twice air inlet and secondary air inlet cell structure, this structure comprises secondary air inlet mouth 6 and secondary air inlet chamber 5.The outer wall of mixing chamber 3 and spray chamber 7 is close in secondary air inlet chamber 5, is the straight tube of an annular.Be provided with simultaneously distribution orifice 8 in the secondary air inlet chamber, distribution orifice 8 is arranged along the circumferential annular of spray chamber 7; Be welded with cyclone 4 between mixing chamber 3 and spray chamber 7, cyclone 4 not only has eddy flow groove 13 at periphery, and at central part bellmouth 14 or arcuate socket 15 is arranged.

As shown in Figure 2, when the central part of cyclone 4 was bellmouth 14, the front portion was a tapered conical, and the centre is a cylindrical shape, and the rear portion is the flaring taper.

As shown in Figure 3, when the central part of cyclone 4 was arcuate socket 15, the front portion was the convergent arc, and the rear portion is the diffusion arc.

The course of work of this catalytic cracking feed nozzle is: a part of steam (or dry gas) mixes at mixing chamber 3 with feedstock oil from oil inlet 2 through air inlet 1, through cyclone 4 rotation after-acceleration ejections.Cyclone can mix steam (or dry gas) and fluid effectively, and utilizes turning effort with liquid generate film, utilizes gas at a high speed to destroy the intermolecular surface tension of liquid grain, and liquid film is broken into particle, realizes the primary atomization of feedstock oil.Another part steam (or dry gas) enters secondary air inlet chamber 5 from secondary air inlet mouth 6, and secondary gas utilizes the speed difference of gas and fluid through distribution orifice 8 ejection at a high speed, further oil film is torn up; Also destroyed the viscous flow of the elaioleucite behind the primary atomization simultaneously, avoided little elaioleucite to aggregate into the phenomenon of big liquid grain once more, realized the secondary-atomizing of fluid at playpipe tube wall place.Further gas-liquid mixture is by playpipe 9, after flat collar extension 11 ejections of shower nozzle 10.Utilize the contraction and the diffusion of spray orifice, a constant pressure drop and the speed of generation, liquid crushing becomes particulate the most at last, finishes the atomizing for the third time of feedstock oil.

The result of the test of the utility model model machine is as follows: the one, and atomization is stable, and atomizing effect is good, and the green coke amount and the operating flexibility that can reduce catalytic reaction are big; The 2nd, can reduce jet velocity, avoid catalyst breakage and cause device catalyst consumption to increase; The 3rd, wear resistance is good, is expected long-term operation; The 4th, can replace atomizing steam with the atomizing dry gas, thereby reduce the energy consumption of device.

Claims

1, a kind of atomized feed nozzle, comprise an air inlet (1), oil inlet (2), mixing chamber (3), spray chamber (7), cyclone (4), accelerating sections (12), playpipe (9), shower nozzle (10) and outer spray (11), it is characterized in that adopting the structure of secondary air inlet chamber, this structure comprises secondary air inlet mouth (6) and secondary air inlet chamber (5), the outer wall of mixing chamber (3) and spray chamber (7) is close in secondary air inlet chamber (5), is the straight tube of an annular; Be provided with simultaneously distribution orifice (8) in secondary air inlet chamber (5), distribution orifice (8) is arranged along the circumferential annular of spray chamber (7); Welding cyclone (4) between mixing chamber (3) and spray chamber (7), cyclone (4) not only has eddy flow groove (13) at periphery, and at central part bellmouth (14) or arcuate socket (15) is arranged.

2, atomized feed nozzle as claimed in claim 1, when the central part that it is characterized in that cyclone (4) was bellmouth (14), the front portion was a convergent shape, and the centre is a cylindrical shape, and the rear portion is the flaring taper.

3, atomized feed nozzle as claimed in claim 1, when the central part that it is characterized in that cyclone (4) was arcuate socket (15), the front portion was the convergent arc, the rear portion is the diffusion arc.