Integrated method and apparatus for catalytic cracking of heavy oil and production of syngas

Abstract

The present disclosure provides an integrated method and apparatus for catalytic cracking of heavy oil and production of syngas. A cracking-gasification coupled reactor having a cracking section and a gasification section is used as a reactor in the method. A heavy oil feedstock is fed into a cracking section to contact with a bed material in a fluidized state that contains a cracking catalyst, a catalytic cracking reaction is conducted under atmospheric pressure to obtain light oil-gas and coke. The coke is carried downward by the bed material into a gasification section to conduct a gasification reaction to generate syngas; the syngas goes upward into the cracking section to merge with the light oil-gas, and is guided out from the coupled reactor and enter a gas-solid separation system. Oil-gas fractionation is performed to a purified oil-gas product output from the gas-solid separation system to collect light oil and syngas products.

Claims

1. An integrated method for catalytic cracking of heavy oil and production of syngas, wherein a cracking-gasification coupled reactor having a cracking section and a gasification section that are internally connected with each other is used as a reactor, the integrated method comprises: feeding a heavy oil feedstock into the cracking section in an upper portion of the cracking-gasification coupled reactor to contact with a bed material in a fluidized state that contains a cracking catalyst, a catalytic cracking reaction is conducted under atmospheric pressure to obtain light oil-gas and coke; the coke is carried downward by the bed material into the gasification section in a lower portion of the cracking-gasification coupled reactor to conduct a gasification reaction to generate syngas; the syngas goes upward in the cracking-gasification coupled reactor into the cracking section to merge with the light oil-gas, and is guided out from the coupled reactor to a gas-solid separation system; subjecting the light oil-gas and the syngas in the gas-solid separation system to at least a first-stage gas-solid separation, and bed material particles separated out are collected and divided into two parts, and returned to the cracking section and the gasification section, respectively, to form a first-stage circulation and a second-stage circulation of the bed material particles accordingly; and performing oil-gas fractionation to a purified oil-gas product output from the gas-solid separation system to collect light oil and syngas products; wherein, the integrated method, before the coke is carried by the bed material downward into the gasification section in a lower portion of the cracking-gasification coupled reactor, further comprises performing a steam stripping processing and a particle size refining processing sequentially to the downward bed material particles.

2. The integrated method according to claim 1, wherein, subjecting the light oil-gas and the syngas in the gas-solid separation system comprises: the first-stage gas-solid separation and further comprises a sequential second-stage gas-solid separation, wherein first-stage bed material particles and second-stage bed material particles are separated out in sequence and the purified oil-gas product is collected; the first-stage bed material particles are returned to the cracking section to form the first-stage circulation; and the second-stage bed material particles are returned to the gasification section to form the second-stage circulation; wherein, a particle size of the first-stage bed material particles is greater than a particle size of the second-stage bed material particles; or, subjecting the light oil-gas and the syngas in the gas-solid separation system to the first-stage gas-solid separation, and the bed material particles collected are sent back to the cracking section and the gasification section, respectively, through a material returning and distributing mechanism by means of fluidizing gas blowback, to form the first-stage circulation and the second-stage circulation.

3. The integrated method according to claim 2, wherein, a particle size of the first-stage bed material particles is a, and 30≤a≤200 μm; a particle size of the second-stage bed particles is b, and 5<b<30 μm.

4. The integrated method according to claim 1, wherein, a reaction temperature of the cracking reaction is 450-700° C., an agent-oil ratio is 4-20, a reaction time is 1-20 s, and an apparent gas velocity is 1-20 m/s, wherein the agent-oil ratio is a mass ratio between an amount of the bed material fed and an amount of the heavy oil feedstock fed.

5. The integrated method according to claim 1, wherein, a reaction temperature of the gasification reaction is 850-1200□, a reaction pressure is atmospheric pressure, an apparent gas velocity is 0.1-5.0 m/s, and a residence time is 1-20 min.

6. The integrated method according to claim 2, wherein, before the coke is carried by the bed material downward into the gasification section in a lower portion of the cracking-gasification coupled reactor, further comprising performing a steam stripping processing and a particle size refining processing sequentially to the downward bed material particles.

7. The integrated method according to claim 3, wherein, before the coke is carried by the bed material downward into the gasification section in a lower portion of the cracking-gasification coupled reactor, further comprising performing a steam stripping processing and a particle size refining processing sequentially to the downward bed material particles.

8. The integrated method according to claim 4, wherein, before the coke is carried by the bed material downward into the gasification section in a lower portion of the cracking-gasification coupled reactor, further comprising performing a steam stripping processing and a particle size refining processing sequentially to the downward bed material particles.

9. The integrated method according to claim 5, wherein, before the coke is carried by the bed material downward into the gasification section in a lower portion of the cracking-gasification coupled reactor, further comprising performing a steam stripping processing and a particle size refining processing sequentially to the downward bed material particles.

10. The integrated method according to claim 1, wherein, conditions of the steam stripping processing are: a mass ratio of water vapor to the heavy oil feedstock is 0.1-0.3, a temperature of the water vapor is 200-400° C., and an apparent gas velocity of the water vapor is 0.5-5.0 m/s.

11. The integrated method according to claim 1, wherein Conradson carbon residue of the heavy oil feedstock is larger than or equal to 8%.

12. The integrated method according to claim 2, wherein Conradson carbon residue of the heavy oil feedstock is larger than or equal to 8%.

13. The integrated method according to claim 3, wherein Conradson carbon residue of the heavy oil feedstock is larger than or equal to 8%.

14. The integrated method according to claim 4, wherein Conradson carbon residue of the heavy oil feedstock is larger than or equal to 8%.

15. The integrated method according to claim 5, wherein Conradson carbon residue of the heavy oil feedstock is larger than or equal to 8%.

16. The integrated method according to claim 10, wherein Conradson carbon residue of the heavy oil feedstock is larger than or equal to 8%.

17. An integrated apparatus for catalytic cracking of heavy oil and production of syngas configured to implement the integrated method according to claim 1, comprising: a cracking-gasification coupled reactor, comprising a cracking section and a gasification section that are internally connected with each other, and an oil-gas outlet located on top of the cracking-gasification coupled reactor and connected with the cracking section; the cracking section is located above the gasification section; the cracking section is provided with a feedstock inlet and a first solid phase inlet; the gasification section is provided with a second solid phase inlet; a gas-solid separation system, comprising: a material inlet, a gas phase outlet and a solid phase outlet; a first gas-solid separator and a second gas-solid separator, the first gas-solid separator comprises a first material inlet, a first gas phase cutlet and a first solid phase outlet, and the second gas-solid separator comprises a second material inlet, a second gas phase outlet and a second solid phase outlet; and a fractionating tower, comprising: a fractionating tower inlet and multiple light component outlets; wherein the oil-gas outlet of the cracking-gasification coupled reactor is connected with the first material inlet, the first gas phase outlet is connected with the second material inlet, and the second gas phase outlet is connected with the fractionating tower inlet; the first solid phase outlet is connected with the first solid phase inlet of the cracking section; the second solid phase outlet is connected with the second solid phase inlet of the gasification section; wherein the gas-solid separation system is located outside the cracking-gasification coupled reactor.

Description

BRIEF DESCRIPTION OF DRAWING(S)

(1) FIG. 1 is a schematic diagram of an integrated apparatus for catalytic cracking of heavy oil and production of syngas in an embodiment of the present disclosure.

(2) FIG. 2 is a schematic diagram of an integrated apparatus for catalytic cracking of heavy oil and production of syngas in an embodiment of the present disclosure.

(3) FIG. 3 is a schematic diagram of an integrated apparatus for catalytic cracking of heavy oil and production of syngas in another embodiment of the present disclosure.

DESCRIPTION OF REFERENCE NUMERALS

(4) 1: cracking section; 2: gasification section; 3: gas-solid separation system; 4: fractionating tower; 5: steam stripping section; 6: particle size refining section; 7: atomizing device; 8: washing section; 9: solid phase channel; 10: preheating mixer; 11: material returning and distribution mechanism; 31: first gas-solid separator; 32: second gas-solid separator; 100: cracking-gasification coupled reactor; a: gasification agent; b: solid ash; c: heavy oil feedstock; d: cracking catalyst; e: syngas; f: to-be-separated material flow; g: first-stage bed material particles; h: preliminary purified oil-gas product; i: second-stage bed material particles; j: purified oil-gas product; k: gasification catalyst; m: bed material particles of first-stage circulation; n: bed material particles of second-stage circulation; o: fluidized gas.

DESCRIPTION OF EMBODIMENTS

(5) Content of the present disclosure is described more specifically below in combination with the following embodiments. It should be understood that the embodiment of the present disclosure is not limited to the following embodiments, and any formal adaptations and/or changes made to the present disclosure will fall within the scope of protection of the present disclosure.

(6) The following embodiments, unless otherwise indicated, may be implemented by using conventional apparatus/instruments/structures/components or the like in the art.

Embodiment 1

(7) FIG. 1 is a schematic diagram of an integrated apparatus for catalytic cracking of heavy oil and production of syngas in an embodiment of the present disclosure, the apparatus includes at least:

(8) a cracking-gasification coupled reactor 100, including a cracking section 1 and a gasification section 2 that are internally connected to each other and an oil-gas outlet located on the top of the cracking-gasification coupled reactor 100 and connected with the cracking section 1; the cracking section 1 is located on an upper portion of the gasification section 2; the cracking section 1 is provided with a feedstock inlet, a first solid phase inlet; the gasification section 2 is provided with a second solid phase inlet; wherein the feedstock inlet of the cracking section 1 leads directly to the fluidized bed material;

(9) specifically, the abovementioned cracking-gasification coupled reactor 100 may specifically be obtained by suitable modification and assembly of a cracking reactor and a gasification reactor commonly used in the art. Where, the cracking reactor may, for example, be a fluidized bed reactor, the bottom end of which is interconnected with the top end of the gasification reactor. Preferably, the cracking reactor and the gasification reactor are installed coaxially to facilitate the transport and circulation of materials;

(10) as such, the cracking section 1 may include a fluidized bed, such that solid particles such as bed material of the cracking section 1 can stay in a fluidized state by the action of the fluidized bed, and serve as carriers for the cracking reaction;

(11) the gasification section 2 may include a fluidized bed, such that solid particles such as bed material of the gasification section 2 can stay in a fluidized state by the action of the fluidized bed, and contact with a gasification agent a for gasification reaction; the gasification section 2 is also provided with a gasification agent inlet for injecting the gasification agent a and a slag outlet for the output of impurities that cannot be reactively transformed such as solid ash b;

(12) a gas-solid separation system 3, including a first gas-solid separator 31 and a second gas-solid separator 32; where the first gas-solid separator 31 includes a first material inlet, a first gas phase outlet and a first solid phase outlet, and the second gas-solid separator 32 includes a second material inlet, a second gas phase outlet and a second solid phase outlet; and

(13) a fractionating tower 4, including a fractionating tower inlet and multiple light component outlets;

(14) where the gas-solid separation system 3 is located outside the cracking-gasification coupled reactor 100, the oil-gas outlet of the cracking-gasification coupled reactor 100 is connected with the first material inlet, the first gas phase outlet is connected with the second material inlet, and the second gas phase outlet is connected with the fractionating tower inlet; the first solid phase outlet is connected with the first solid phase inlet of the cracking section 1; and the second solid phase outlet is connected with the second solid phase inlet of the gasification section 2.

(15) The abovementioned first gas-solid separator may be one or more cyclone separators connected in series or parallel with each other, and the second gas-solid separator may be one or more cyclone separators connected in series or parallel with each other.

(16) On the abovementioned basis, the interior of the cracking-gasification coupled reactor 100 of FIG. 1 further includes:

(17) a steam stripping section 5, the steam stripping section 5 may include a steam stripping baffle, thereby removing oil-gas from the surface of bed material particles in the downward process by injecting vapor;

(18) a particle size refining section 6, the particle size refining section 6 may include a steam jet grinder that grinds the bed material particles after steam stripping by injecting vapor;

(19) an atomizing apparatus 7, which is located in the cracking section 1 and is connected with the feedstock inlet of the cracking section 1, and configured to atomize the heavy oil feedstock c;

(20) a washing section 8, which is provided above the cracking section 1 and is connected with the cracking section 1, and configured to wash and cool down a to-be-separated material flow f that is about to enter the gas-solid separation system 3, and remove part of bed material particles in the to-be-separated material flow f.

(21) In addition, a solid phase channel 9 is also provided between the cracking section 1 and the gasification section 2 of the cracking-gasification coupled reactor 100, the solid phase channel 9 is located on the outside of the cracking-gasification coupled reactor 100, and a feedstock inlet of the solid phase channel 9 is located below a particle size refining section 6, configured to lead bed material particles refined and grinded by the particle size refining section 6 downward into the gasification section 2.

(22) The cracking-gasification coupled reactor 100 also includes a preheating mixer 10 on the outside, the preheating mixer 10 is provided with a heavy oil feedstock inlet, a first catalyst inlet and a feedstock outlet, where, the feedstock outlet of the preheating mixer 10 is connected with the feedstock inlet of the cracking section 1, so that the heavy oil feedstock and a cracking catalyst d are mixed and preheated in the preheating mixer 10, and then enter the cracking section 1.

(23) An integrated method for catalytic cracking of heavy oil and production of syngas by using the integrated apparatus provided in the present embodiment is briefly described as follows.

(24) The heavy oil feedstock c and the cracking catalyst d are fed into the preheating mixer 10 respectively through the heavy oil feedstock inlet and the first catalyst inlet of the preheating mixer 10, and then transferred to the cracking section 1 after being fully mixed and preheated, contacting with fluidized bed material for a catalytic cracking reaction after being atomized by the atomization apparatus 7, to obtain light oil-gas and coke respectively. The coke is attached to the surface of the bed material particles, and thus forming bed material particles with different particle sizes. A part of heavily coked bed material particles goes downward under the action of gravity, and during the downward process, the light oil-gas remaining on the surface of the bed material particles is removed firstly through the steam stripping section 5, and then the bed material particles is cut and refined by a particle size refining section 6. Finally, cut and refined bed material particles go downward through the solid phase channel 9 to the gasification section 2.

(25) In the gasification section 2, the abovementioned refined bed material particles undergo a gasification reaction with the gasification agent that has entered the gasification section 2 via the gasification agent inlet, so as to obtain syngas e and a regenerated bed material. Moreover, the solid ash b that cannot react during a gasification process of bed material particles may be discharged through the slag discharge port from the cracking-gasification coupled reactor 100 after being accumulated. Heavy metals, cracking catalysts and the like in the solid ash b may be recycled by subsequent processes.

(26) With the generation of the syngas, and being driven by the gasification agent a, the syngas e (which carries part of the bed material particles (including the regenerated bed material) during the upward process) goes upward and enters into the cracking section 1, and thus providing reaction heat and reaction atmosphere to the catalytic cracking reaction of heavy oil (the amount of syngas going upward may be controlled by regulating the type of gasification agent, the gas velocity and the like, and thereby ensuring that an internal material flow of the cracking-gasification coupled reactor 100 matches with an energy flow), and then the syngas e merges with the light oil-gas. The to-be-separated material flow f (the light oil-gas, the syngas and bed material particles entrained therein) goes upward, and passes through the washing section 8 to exchange heat with low-temperature liquid in the washing section 8 to cool down the to-be-separated material flow f and remove part of bed material particles from the to-be-separated material flow f, the part of bed material particles removed falls back to the cracking section 1 and continue to act as reactive carriers; after being cooled down by the washing section 8, the to-be-separated material flow f is guided out from the cracking-gasification coupled reactor 100 via the oil-gas outlet, and enter the first gas-solid separator 31 via the first material inlet, where the preliminary separation (the first-stage gas-solid separation) is carried out in the first gas-solid separator 31 to separate out a first-stage bed material particle g (a particle size range of which is a, and 30≤a≤200 μm) and the preliminary purified oil-gas product h.

(27) In that case, the first-stage bed material particle g is exported through the first solid phase outlet, and enters the cracking section 1 through the first solid phase inlet to be continuously served as a cracking reaction carrier, and thus forming a first-stage circulation.

(28) After being preliminarily purified, the oil-gas product h is exported through the first gas phase outlet, and enters the second gas-solid separator 32 through the second material inlet for a secondary separation (the second-stage gas-solid separation) in the second gas-solid separator 32, to separate out a second-stage bed material particle i (a particle size range of which is b, and 5<b<30 μm) and a purified oil-gas product j.

(29) As such, the second-stage bed material particles i are exported through the second solid phase outlet, and enters the gasification section 2 through the second solid phase inlet for a gasification reaction, and thus forming a secondary circulation.

(30) It can be understood that, the first-stage bed material particles g of the first-stage circulation and the bed material particles in the cracking section 1 would continue to be recycled after being mixed (a part of mixed bed material particles goes downward into the gasification section 2 as a feedstock of the gasification reaction, a part of mixed bed material particles remains in the cracking section 1 as a cracking reaction carrier, and a part of mixed bed material particles entrained within the light oil-gas and the syngas enters the gas-solid separation system 3); after entering the gasification section 2, the second-stage bed material particle i of the second-stage circulation undergoes a gasification reaction with the abovementioned bed material particles that go downward from the cracking section 1 through the solid phase channel 9 in the gasification section 2, to generate the syngas e, the syngas e will carry part of the bed material particles in the gasification section 2 upward into the cracking section 1.

(31) Purified oil-gas product j is exported through the second gas phase outlet, and enters the fractionating tower 4 through the fractionating tower inlet for fractionation, and thus products, such as light oil, cracked gas (dry gas, liquefied gas or the like) and syngas or the like, would be exported respectively through multiple light fraction outlets of the fractionating tower 4. Certainly, a further separation and fraction may be performed by providing multiple fractionating towers to obtain liquid products with different distillation range components, where, heavy oil (including part of bed material particles and the like) in the bottom of the fractionating tower may be mixed with the heavy oil feedstock c and recirculated into the cracking-gasification coupled reactor 100 for processing.

(32) The conditions for the abovementioned cracking reaction are: a reaction temperature is 450-700° C., a reaction pressure is 0.1 MPa, a reaction time of 1-20 s, and an agent oil ratio is 4 to 20. The heavy oil feedstock may be preheated to 220-350° C. before entering the cracking section.

(33) The conditions for the abovementioned gasification reaction are: a reaction temperature is 850-1200° C., a reaction pressure is 0.1 Mpa, an apparent gas velocity is 0.1-5 m/s, and a residence time of the bed material particles is 1 to 20 min.

(34) The abovementioned gasification agent in the gasification reaction may be one or more of water vapor, oxygen, oxygen-rich air and air.

(35) The conditions for the abovementioned steam stripping processing are: a mass ratio of water vapor to heavy oil feedstock is 0.1-0.3, a temperature of the water vapor is 200-400° C., and an apparent gas velocity of the water vapor in vapor striping is 0.5-5.0 m/s.

(36) In the present embodiment, the bed material particles may include an inert carrier, and certainly, some of other solid particles (for example, the cracking catalyst of the present embodiment, a gasification catalyst which has catalytic activity for the gasification reaction as described below or the like) may be added as reaction carriers as required and involved in a circulation process of the integrated process of the present embodiment, the solid particles added may also be regarded as a component of the bed material of the present embodiment. In a specific embodiment, the aforementioned inert carrier may be one or more of coke powder, quartz sand and other materials, and preferably, using the coke powder as the bed material.

(37) Generally, a particle size distribution range of the abovementioned bed material may be 10-500 μm, and further, 20-200 μm.

(38) The abovementioned cracking catalyst may include one or more of kaolin, clay (or modified clay), alumina, silica sol, montmorillonite, illite, silicon-alumina microspheric contact agent, an FCC industrial balancing agent and the like. In an embodiment, a silicon-aluminum microspheric contact agent with a micro-reactive index of about 10-20 is used as a cracking catalyst.

(39) The amount of the abovementioned added cracking catalyst may account for 0.5%-5% (by mass) of the total amount of the bed material.

(40) In the present embodiment, the amount of the cracking catalyst added to the preheating mixer 10 to be mixed with the heavy oil feedstock is about 0.5%-5% of the amount of added heavy oil. Certainly, depending on the total amount of the cracking catalyst added into the coupled reactor, for example, when the total amount of the added cracking catalyst is greater than the amount of the abovementioned cracking catalyst mixed with the heavy oil feedstock, a remaining part of the cracking catalyst may enter the cracking section by other means in addition to the abovementioned part of the cracking catalyst being mixed with the heavy oil feedstock that enters the cracking section. As shown in FIG. 2, a cracking catalyst inlet may be provided at the cracking section 1 and/or the first-stage circulation for the addition of the remaining part of the cracking catalyst.

(41) In addition, in another embodiment, the heavy oil feedstock may enter the cracking section 1 separately via a feedstock inlet, rather than being preheated and mixed with the cracking catalyst, in that case, the cracking catalyst enters the cracking section 1 by other means. In the integrated apparatus as shown in FIG. 2, no preheating mixer is provided, and the heavy oil feedstock is allowed to enter the cracking section 1 directly via a feedstock inlet, and the cracking catalyst may enter the cracking section 1 through the abovementioned cracking catalyst inlet.

(42) In addition, a gasification catalyst k may be added into the gasification section 2, for example, a corresponding second gasification catalyst inlet may be provided at the gasification section and/or the second-stage circulation and/or the solid phase pass 9 for the addition of the gasification catalyst k. The amount of added gasification catalyst is generally 0.05-0.3 (by mass) of the total amount of the bed material.

(43) Generally, the abovementioned gasification catalyst may include one or more of a natural ore, a synthetic material and a derivative compound, which contain a single metal or a combination of multiple metals of an alkali metal, an alkaline-earth metal or a Group VIII metal, and an industrial solid waste, such as sludge, slag and blast-furnace dust, which is rich in an alkali metal and an alkaline-earth metal. For example, in an embodiment, an alkaline metal salt compound may be used as the gasification catalyst, where, the compound is composed mainly of potassium carbonate (with content of about 91.5%), with the rest are a carbonate of calcium, magnesium and the like.

(44) In the present embodiment, Conradson carbon residue of the heavy oil feedstock is larger than or equal to 8%. The heavy oil feedstock may be one heavy oil or a heavy oil mixture of any proportion, such as thickened oil, highly thickened oil, oil sand asphalt, atmospheric residual oil, vacuum residual oil, catalytic cracking slurry, solvent deoiled asphalt or the like, or may be one derived heavy oil or a derived heavy oil mixture of any proportion, such as heavy tar and residual oil in a coal pyrolysis or a liquefaction process, heavy oil produced by retorting oil shale, a low-temperature pyrolysis liquid product in biomass or the like.

Embodiment 2

(45) The integrated method and the integration apparatus used in the present embodiment are generally the same as embodiment 1, and thus the following only illustrates the differences between the present embodiment and embodiment 1 without repeating the same part, reference may be made to the details of embodiment 1.

(46) FIG. 3 is a schematic diagram of an integrated apparatus for catalytic cracking of heavy oil and production of syngas in the present embodiment, which has differences from the integrated apparatus of embodiment 1 (FIG. 1) as follows.

(47) (1) Heavy oil feedstock inlet: the cracking section 1 of the cracking-gasification coupled reactor 100 includes a first feedstock inlet and a second feedstock inlet (i.e., two feedstock inlets), where the first feed inlet leads directly to the fluidized bed material and the second feed inlet leads to the washing section 8.

(48) (2) Gas-solid separation system 3: the gas-solid separation system 3 includes a material inlet, a gas phase outlet and a solid phase outlet;

(49) in that case, the gas-solid separation system 3 is located outside the cracking-gasification coupled reactor 100, with the oil-gas outlet of the cracking-gasification coupled reactor 100 being connected with the material inlet, the first solid phase inlet of the cracking section 1 and the second solid phase inlet of the gasification section 2 being connected respectively with the solid phase outlet of the gas-solid separation system 3, and the gas-solid phase outlet of the gas-solid separation system 3 being connected to the fractionating tower inlet.

(50) Furthermore, a material returning and distributing mechanism 11 is also provided outside the cracking-gasification coupled reactor 100 between the gas-solid separation system 3 and the cracking-gasification coupled reactor 100, with the solid phase outlet of the gas-solid separation system 3 being connected respectively with the first solid phase inlet and the second solid phase inlet via the material returning and distributing mechanism 11. The material returning and distributing mechanism 11 includes a material returning inlet and a material returning outlet, with the material returning inlet being connected with the solid phase outlet of the gas-solid separation system 3, and the material returning outlet being connected with the first solid phase inlet and the second solid phase inlet respectively.

(51) The abovementioned first gas-solid separator may be formed by one or more cyclone separators connected in series or in parallel to each other.

(52) The differences between the integration method of the present embodiment and embodiment 1 are briefly described as follows.

(53) (1) Heavy oil feedstock c enters the cracking-gasification coupled reactor in two paths: the heavy oil feedstock c is divided into two parts, where, one part of the heavy oil feedstock c is preheated and mixed with the cracking catalyst d in the preheating mixer 10 and transported to the cracking section 1 via the first feedstock inlet, and then contacts with the fluidized bed material for a catalytic cracking reaction after being atomized by the atomization apparatus 7; the other part of the heavy oil feedstock c is fed into the cracking-gasification coupled reactor 100 via the second feedstock inlet, and firstly passes through the washing section 8 for heat exchange with the to-be-separated material flow f which is about to enter the gas-solid separation system 3, and then goes downward into the cracking section 1, and contacts with the fluidized bed material for catalytic cracking reaction.

(54) (2) The to-be-separated material flow f cooled down by the washing section 8 is led out from the cracking-gasification coupled reactor 100 through the oil-gas outlet and enters the gas-solid separation system 3 through the material inlet.

(55) The gas-solid separation system 3 of the present embodiment is a first-stage gas-solid separation (only one gas-solid separation), and the separated bed material particles are exported through the solid phase outlet and enter the material returning and distributing mechanism 11 through the material returning inlet, and enter the cracking section 1 and the gasification section 2 respectively in two paths separately from the material returning outlet under the blowback action of the fluidizing gas o, where the bed material particles entering the cracking section 1 through the first solid phase inlet are first-stage circulation bed particles m, and the bed material particles entering the gasification section 2 through the second solid phase inlet are second-stage circulation bed particles n.

(56) The abovementioned fluidizing gas o may include a mixture of one or more gases of water vapor, nitrogen, or syngas generated in the present disclosure. A blowback gas velocity of the fluidizing gas is 0.2-3.0 m/s.

Application Embodiment

(57) In order to illustrate effects of the present disclosure, the Venezuelan vacuum residual oil was tested by using the apparatus and process shown in embodiment 1.

(58) Test 1. Coke powder was used as the bed material; no cracking catalyst and gasification catalyst were added.

(59) Test 2. Coke powder with silica-aluminum microspheric contact agent (about 5% of the total bed material) as bed material, no gas catalyst was added.

(60) Test 3. Coke powder and alkaline metal salt compounds (about 5% of the total bed material) were used as the bed material; no cracking catalyst was added.

(61) The properties of the heavy oil feedstock used in the present application embodiment are shown in Table 1. The heavy oil feedstock has high oil density, high residual carbon value, low H/C ratio, high contents of asphaltene and heavy oil fraction greater than 500° C., and contains high contents of sulfur, nitrogen and heavy metal components, and has a serious tendency to coke in the traditional catalytic cracking process, which is prone to lead to inactivation of catalyst due to rapid coke deposition or heavy metal poisoning.

(62) TABLE-US-00001 TABLE 1 Sample name Venezuelan residual oil Density (20° C.)/g .Math. cm.sup.−3 1.0251 Kinematic viscosity (100° C.)/mm.sup.2 .Math. s.sup.−1 4080 Conradson carbon residue/wt % 21.15 C/wt % 84.74 H/wt % 9.96 S/wt % 0.75 N/wt % 3.64 n(H)/n(C) 1.41 Saturate/wt % 19.14 Aromatics/wt % 43.75 Colloid/wt % 24.7 Asphaltene/wt % 12.41 Ni/ppm 99 V/ppm 423 Initial boiling point 357 10% 394 30% 477 50% 558 70% 636 90% 701 Final boiling point 795 VGO ratio (350-500° C.) 36.00% Heavy oil fraction ratio (>500° C.) 64.00%

(63) The coke powder used in this application example has a particle size of 20-120 μm, which is mainly fixed carbon, with a dense carbon layer structure on the surface, and the specific composition of components is shown in Table 2 (which may be determined by conventional industrial analysis).

(64) A silica-aluminum microspheric contact agent used in the present application embodiment (which may be homemade using conventional methods) has a particle size distribution of 20-100 μm and a micro-reactivity index about 10-20, and the specific composition of components is shown in Table 2 (which may be determined by an X-ray fluorescence spectroscopy (XRF) analytical method, where an excited sample is measured, and the type and content of the various elements are finally obtained according to specific energy and wavelength characteristics of secondary X-rays emitted by different elements), where, alkali metal oxides are mainly Na.sub.2O and K.sub.2O, and the other components are mainly MgO, Fe.sub.2O.sub.3 and a small amount of rare earth metal oxides.

(65) The main component of the alkaline metal salt compounds used in the present application embodiment is potassium carbonate (content of about 91.5%), and the rest are carbonates of calcium, magnesium and the like.

(66) TABLE-US-00002 TABLE 2 Volatile Ash Fixed carbon component Coke powder 0.63 91.42 7.95 (wt %, dry basis) Aluminum Silicon Alkali metal Other oxide dioxide oxide components Silicon-aluminum 26.79 67.38 0.56 3.02 microspheric contact agent (wt. %)

(67) In addition, other reaction parameters of the present application embodiment are listed in Table 3.

(68) TABLE-US-00003 TABLE 3 Ratio of Apparent Reactive agent to gas Temperature time oil Pressure velocity Cracking 476° C. 16 s 7.5 0.1 MPa 2.5 m/s reaction Gasifi- Apparent Reactive cation gas Temperature time agent Pressure velocity Gasifi- 850° C. 600 s Water 0.1 MPa 0.2 m/s cation vapor + reaction oxygen Apparent gas velocity of Ratio of water Temperature water vapor vapor to oil Steam 350° C. 1.25 m/s 0.20 stripping processing

(69) After the processing of the abovementioned heavy oil feedstock in this application embodiment, good cracking product distribution and syngas product distribution were achieved in Test 1-Test 3, where a yield of liquid over 74%, and a yield of syngas (including H.sub.2 and CO) over 68% can be achieved, with most of the syngas products being H.sub.2.

(70) To further illustrate positive effects of the addition of the cracking catalyst and gasification catalyst, detailed cracking product distribution obtained from Test 1 and Test 2 is presented in Table 4, and detailed gasification syngas product distribution obtained from Test 1 and Test 3 is presented in Table 5.

(71) TABLE-US-00004 TABLE 4 Experiment No. Test 1 Test 2 Yield of gas/wt % 6.6 5.5 Yield of liquid/wt % 74.5 77.0 Yield of coke/wt % 18.9 17.7 Gasoline fraction/wt % 2.6 11.1 Diesel fraction/wt % 6.9 18.1 Vacuum fraction oil/wt % 40.7 34.1 Heavy oil fraction/wt % 24.3 13.1

(72) It can be seen from Table 4 that good distribution of cracking products can be obtained in both Test 1 and Test 2, which can significantly improve the yield of light oil and inhibit the production of coke. Compared with the initial residual carbon value of the heavy oil feedstock, a ratio of coke yield to residual carbon is about 0.8-0.9, which is much smaller than a coke/residual carbon ratio of 1.4-1.6 in the delayed coking processing; liquid yields are approximately 74.5% and 77.0% respectively, where the liquid contains some of the heavy oil fractions greater than 500° C., which may be subsequently processed by refining.

(73) However, by comparing the cracking product distributions of Test 1 and Test 2, it can be seen that addition of the silica-aluminum microspheric contact agent with some catalytic activity leads to a higher liquid yield and a lower gas and coke yield, indicating that the introduction of a cracking catalyst with catalytic activity as a bed material resulted in a better cracking performance than an inert carrier such as coke powder, which was mainly used in the thermal cracking reaction alone, as a bed material. The simulated distillation results of the liquid products also indicates that, the heavy oil fraction of the oil products was lower and the light gasoline and diesel fraction was higher when the silicon-aluminum microspheric contact agent was used as the reaction bed material than the coke powder, which proved that the silicon-aluminum microspheric contact agent with a certain activity had better reaction performance in the cracking of heavy oil.

(74) TABLE-US-00005 TABLE 5 Experiment No. Test 1 Test 3 H.sub.2/vol % 46.6 54.3 CO/vol % 34.9 14.3 CO.sub.2/vol % 16.1 30.7 CH.sub.4 and the like vol % 2.4 0.7

(75) It can be seen from Table 5 that, the sum of volume fractions of H.sub.2 and CO in the syngas obtained in Test 1 is about 82%, with the content of H.sub.2 about 47% and the content of CO about 35% in the gas. By comparing Test 3 with Test 1, it can be seen that by adding some of alkali metal salts, the content of H.sub.2 in the syngas is increased by 7.7 percentage points due to a catalytic reaction for vapor transformation, which better meets the requirements of the subsequent process for hydrogen preparation. Besides, it should be noted that by adding alkaline metal salts, the reaction time of a gasification reaction in the gasification section in test 3 is reduced by about 40% compared with test 1, and particularly in a forepart of the reaction, the rate of gasification reaction is significantly increased.

(76) Finally, it should be noted that: the above embodiments are merely used for illustrating the technical solutions of the present disclosure, but not being construed as limiting the present disclosure. Although the present disclosure is described in detail with reference to the forgoing embodiments, those ordinary skilled in the art should understand that modifications may still be made to the technical solutions of the forgoing embodiments or equivalent replacements may be made to a part or all of the technical features therein. These modifications or replacements do not make the essence of corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present disclosure.