CN101172922B

CN101172922B - Method for producing propylene with C_4 alkene catalytic pyrolysis

Info

Publication number: CN101172922B
Application number: CN200610117867A
Authority: CN
Inventors: 钟思青; 忻晓琦; 孙凤侠; 杨远飞
Original assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Current assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Priority date: 2006-11-02
Filing date: 2006-11-02
Publication date: 2010-05-12
Anticipated expiration: 2026-11-02
Also published as: CN101172922A

Abstract

The invention relates to a method for preparing propylene with C4olefin through catalyse and schizolysis. The invention mainly solves the problem that the prior axial fixing bed reactor with a thin bed is difficulty in amplifying, thereby influencing the utilization rate of the catalyst and the pressure decreasing of the bed during the process of producing the propylene with C4 and more than C4olefinin normal pressure or negative pressure through the catalyse and the schizolysis as the expanding of the production scale. the invention has the technical proposal that a longitudinal thermal insulation bed reactor which mainly consists of a reactor shell (1), a material inlet pipe (2), an inner distribution drum (3), an outer distribution drum (4), a catalyst basket (5) which is formed by the two distribution drums and the bottom of the shell, a sealing cover (6) positioned on the top of the catalyst basket (5) and an outlet pipe (7) is adopted. The invention preferably solves the technical problems mentioned above. The reactor has the advantages of low pressure decreasing and high catalyst utilization rate. The invention can be applied to the industrial production of preparing the propylene with C4 and more than C4olefin through the catalyse and the schizolysis.

Description

The method that is used for producing propylene with C _ 4 alkene catalytic pyrolysis

Technical field

The present invention relates to a kind of method that is used for producing propylene with C _ 4 alkene catalytic pyrolysis, particularly about a kind of gas-solid radial insulation fix bed reactor that is used for C _ 4 alkene catalytic pyrolysis system propylene.

Background technology

In recent years along with the development of petrochemical industry and the expansion of scale, the diameter of axial restraint bed bioreactor constantly increases, the uniform problem of reactor inner fluid just becomes one of key issue of engineering development, particularly for the reactive system of the thin beds that requires negative pressure, the increasing degree of reactor diameter is bigger, and the uniform fluid distribution problem in its reactor is just more difficult.Fluid distribution in the bed directly influences processes such as heat and mass in the bed and chemical reaction, influences the utilising efficiency of catalyzer and reactor, influences selectivity of catalyst and transformation efficiency.The fluid distribution structure can be divided into two big classes: a class is to increase fluid flow resistance, as packing layer or the porous plate that percentage of open area is less are set before beds.The essence of this kind method is that the impinging jet of formation causes the radial pressure gradient when making gas enter reactor by inlet pipeline on packing layer or porous plate, forces air-flow to change and flows to, and is dispersed to the whole reactor cross section.Since have in the air-flow quite a few waste of energy with the irrelevant friction and eddy loss of uniform effect in, efficient is lower; And be not suitable for thin bed reactor.Another kind of is at the fluid inlet place of fixed-bed reactor fluid distributor to be set, and as CN2075277U, US4938422, US368597, its advantage is that fluid is distributed on the reactor cross section more equably, does not cause excessive energy waste again.But to the thin bed reactor of major diameter, the fluid distributor that its Reactor inlet place is provided with requires than higher, the structure of distributor more complicated.

Reaction system for negative pressure, adopt radial fixed-bed reactor, fluid flows through beds along radius or diametric(al), therefore to have a fluid flow area big for radial reactor, the beds pressure drop is reduced greatly, can use advantages such as catalyst particle, the solving device scale enlarges the difficulty of the thin bed axial flow reactor process amplification that brings preferably.

Summary of the invention

Technical problem to be solved by this invention is along with the expansion of axially-located bed reactor diameter in the prior art, exist the reactor fluid sparger of thin bed to require than higher, the structure of distributor more complicated, engineering is amplified difficulty, influence the technical problem of reactor utilization ratio and catalyst selectivity and transformation efficiency and bed pressure drop, a kind of new method that is used for carbon four and above olefin catalytic cracking to produce propylene is provided.Use the radial adiabatic fixed-bed reactor in this method, have fluid and be evenly distributed on reactor is axial, flow area is big, and bed pressure drop is low, be fit to the requirement of carbon four and above olefin catalytic cracking to produce propylene negative pressure technology, make catalyzer can give play to the advantage of its good selectivity and transformation efficiency.

For solving the problems of the technologies described above, the technical solution used in the present invention is as follows: a kind of method that is used for producing propylene with C _ 4 alkene catalytic pyrolysis, rich olefins with carbon containing four and above alkene is a raw material, in temperature of reaction is 480～600 ℃, reaction pressure is 0.02～0.6MPaA, and weight space velocity is 2～20 hours ^-1Under the condition, raw material is by radial adiabatic fixed-bed reactor and silica alumina ratio SiO ₂/ Al ₂O ₃Be at least 10 crystal aluminosilicate catalyzer contact reacts and generate the effluent that contains propylene, through separate propylene product, wherein said radial adiabatic fixed-bed reactor, comprise that reactor shell 1, feed-pipe 2, inside distributor 3, outer distribution tube 4, two distribution tubes and housing bottom form a catalyst basket 5, the capping 6 at catalyst basket 5 tops, outlet pipe 7, inside distributor 3 and the outer tube 4 that distributes are coaxial with reactor shell, and inside distributor 3 and the outer tube 4 that distributes are having aperture with catalyst basket 5 corresponding sections, and percentage of open area is 5～60%.

In the technique scheme, inside distributor 3 and the outer tube 4 that distributes are having aperture with catalyst basket 5 corresponding sections, and percentage of open area divides 2～10 grades, and percentage of open area is 20～45%.Inside distributor 3 and the outer tube 4 that distributes can adopt porous plate 9 and grid 10 combinations, adopt porous plate 9 in runner one side, adopt grid 10 in catalyzer one side, and its grid 10 slits are less than the granularity of catalyzer, and the grid opening rate is 20～60%.The capping 6 at catalyst basket 5 tops of radial reactor can be adopted the capping of band sieve aperture, and percentage of open area is 10～30%.Deflection cone 8 is set in the inside distributor 4.

Gas-solid radial insulation fix bed reactor in carbon four and the above preparing propylene by catalytic cracking olefin technology is to be made of the capping, outlet pipe, deflection cone etc. that tube and housing bottom form a catalyst basket, catalyst basket top that distribute of reactor shell, feed-pipe, inside distributor, the outer tube that distributes, two, sees accompanying drawing 1.

At carbon four and above alkene negative pressure preparing propylene by catalytic cracking technology, the present invention proposes to adopt the gas-solid radial insulation fix bed reactor.Carbon four and above alkene enter inside distributor by the radial reactor feed-pipe, enter the inside and outside beds generation scission reaction that distributes between the tube through shunting, reactant comes together in outer the distribution between tube and reactor shell in the annular channel through the outer tube that distributes, and upwards flows from reactor head outlet pipe outflow reactor.

These radial adiabatic fixed-bed reactor have bigger circulation area, than the advantage of low bed layer pressure drop, can use the negative pressure technological operation, are 480～600 ℃ in temperature of reaction, and weight space velocity is 2～20 hours ^-1, reaction pressure is 0.02～0.1MPaA, can improve the selectivity and the yield of purpose product propylene, has obtained better technical effect.

Description of drawings

Fig. 1 is a gas-solid radial insulation fix bed reactor synoptic diagram of the present invention;

Fig. 2 is porous plate of the present invention and grid synoptic diagram;

In Fig. 1,1 is reactor shell; 2 is feed-pipe; 3 is inside distributor; 4 is the outer tube that distributes; 5 is catalyst basket; 6 is top closure; 7 is outlet pipe; 8 is deflection cone.

In Fig. 2,9 is porous plate; 10 is grid.

The present invention is further elaborated below by embodiment.

Embodiment

[embodiment 1]

200,000 tons of/year carbon four and above preparing propylene by catalytic cracking olefin process using be the gas-solid radial insulation fix bed reactor as shown in Figure 1.1800 millimeters of reactor diameters, 300 millimeters of catalyst bed layer thicknesses, 3000 millimeters of catalyst bed floor heights, inside and outside distribution tube percentage of open area is 30～45%, pressure 0.06MPaA, 500 ℃ of temperature of reaction, air speed 10 hours ^-1, adopt al mole ratio (SiO ₂/ Al ₂O ₃) be 200 ZSM type molecular sieve catalyst, reaction raw materials is ethylene plant's etherificate carbon four, reactor pressure decrease 15KPa, propene yield are 29.5%, yield of ethene 7.05%, transformation efficiency 67.24%.

[embodiment 2]

300,000 tons of/year carbon four and above preparing propylene by catalytic cracking olefin process using be the gas-solid radial insulation fix bed reactor as shown in Figure 1.2400 millimeters of reactor diameters, 500 millimeters of catalyst bed layer thicknesses, 2500 millimeters of catalyst bed floor heights, the capping of band sieve aperture is adopted at the catalyst basket top, and percentage of open area is 10%, and inside and outside distribution tube percentage of open area is 30～45%, 500 ℃ of temperature of reaction, air speed 8h ^-1, pressure 0.07MPaA adopts al mole ratio (SiO ₂/ Al ₂O ₃) be 200 ZSM type molecular sieve catalyst, reaction raw materials is ethylene plant's etherificate carbon four, reactor pressure decrease 25KPa, propene yield are 27.5%, yield of ethene 7.03%, transformation efficiency 68.84%.

[embodiment 3]

400,000 tons of/year carbon four and above preparing propylene by catalytic cracking olefin process using be the gas-solid radial insulation fix bed reactor as shown in Figure 1.3100 millimeters of reactor diameters, 600 millimeters of catalyst bed layer thicknesses, 4300 millimeters of catalyst bed floor heights, the capping of band sieve aperture is adopted at the catalyst basket top, and percentage of open area is 12%, and inside and outside distribution tube percentage of open area is 30～45%, pressure 0.07MPaA, 500 ℃ of temperature of reaction, air speed 5h ^-1, adopt al mole ratio (SiO ₂/ Al ₂O ₃) be 200 ZSM type molecular sieve catalyst, reaction raw materials is ethylene plant's etherificate carbon four, reactor pressure decrease 25KPa, propene yield are 27.33%, yield of ethene 7.12%, transformation efficiency 69.18%.

[comparative example 1～3]

400,000 tons of/year carbon four and the axial insulation fix bed reactor of above preparing propylene by catalytic cracking olefin process using, reactor diameter D=2200 millimeter, 4600 millimeters of tangent line height, beds height H=2000 millimeter, pressure 0.3MPa (absolute pressure), other condition is identical with embodiment 1, reactor pressure decrease 50KPa, propene yield is 22.42%, yield of ethene 6.68%, transformation efficiency 72.90%.

Claims

1. method that is used for producing propylene with C _ 4 alkene catalytic pyrolysis is a raw material with the rich olefins of carbon containing four and above alkene, is 480～600 ℃ in temperature of reaction, and reaction pressure is 0.02～0.6MPaA, and weight space velocity is 2～20 hours ^-1Under the condition, raw material is by radial adiabatic fixed-bed reactor and silica alumina ratio SiO ₂/ Al ₂O ₃Be at least 10 crystal aluminosilicate catalyzer contact reacts and generate the effluent that contains propylene, through separate propylene product, wherein said radial adiabatic fixed-bed reactor, comprise reactor shell (1), feed-pipe (2), inside distributor (3), the outer tube (4) that distributes, two distribution tubes and housing bottom form a catalyst basket (5), the capping (6) at catalyst basket (5) top, outlet pipe (7), inside distributor (3) and the outer tube (4) that distributes are coaxial with reactor shell, and inside distributor (3) and the outer tube (4) that distributes are having aperture with catalyst basket (5) corresponding section, and percentage of open area is 5～60%.

2. according to the right 1 described method that is used for producing propylene with C _ 4 alkene catalytic pyrolysis, it is characterized in that inside distributor (3) and the outer tube (4) that distributes are having aperture with catalyst basket (5) corresponding section, percentage of open area divides 2～10 grades, and percentage of open area is 20～45%.

3. according to the right 1 described method that is used for producing propylene with C _ 4 alkene catalytic pyrolysis, it is characterized in that inside distributor (3) and the outer tube (4) that distributes adopt porous plate (9) and grid (10) combination, adopt porous plate (9) in runner one side, adopt grid (10) in catalyzer one side, its grid (10) slit is less than the granularity of catalyzer, and the grid opening rate is 20～60%.

4. according to the right 1 described method that is used for producing propylene with C _ 4 alkene catalytic pyrolysis, it is characterized in that the capping of being with sieve aperture is adopted in the capping (6) at catalyst basket (5) top of radial reactor, percentage of open area is 10～30%.

5. according to the right 1 described method that is used for producing propylene with C _ 4 alkene catalytic pyrolysis, it is characterized in that being provided with in the reactor inside distributor (4) deflection cone (8).