CN112538378A

CN112538378A - Method and device for co-production of heavy oil lightening and synthesis gas

Info

Publication number: CN112538378A
Application number: CN201910901506.2A
Authority: CN
Inventors: 蓝兴英; 李大鹏; 张玉明; 高金森; 王宁波; 高亚男; 姚晓虹; 黄传峰; 杨会民; 王汝成; 黄勇; 石孝刚; 王成秀; 蒋中山; 张健; 任健
Original assignee: Nanjing Zhonghui Energy Technology Research And Development Center; China University of Petroleum Beijing
Current assignee: Nanjing Zhonghui Energy Technology Research And Development Center; China University of Petroleum Beijing
Priority date: 2019-09-23
Filing date: 2019-09-23
Publication date: 2021-03-23
Anticipated expiration: 2039-09-23
Also published as: CN112538378B

Abstract

The invention provides a method and a device for heavy oil lightening and synthesis gas co-production, which adopt a coupling reactor internally provided with a cracking section and a burning section which are mutually communicated through a material lowering system and a cracking-coke gasification coupling reaction system coupled with a gasification reactor, and the method comprises the following steps: heavy oil raw materials enter a cracking section and contact with fluidized coke powder to generate light oil gas and coke powder particles; the coke powder particles descend through the material descending system to enter a coking section, one part of the coke powder particles which are not completely coked in the coking section returns to the cracking section, and the other part of the coke powder particles is conveyed to the gasification reactor; introducing part of the synthesis gas of the gasification reactor into a cracking section, merging the synthesis gas with the light oil gas, carrying out gas-solid separation, and then carrying out oil-gas fractionation on the output purified oil gas to collect light oil and synthesis gas products; the coke breeze particles that are not completely gasified are returned to the pyrolysis or char stage. The method optimizes the circulation path of coke generated in the cracking reaction of the heavy oil raw material, reduces the energy consumption of the cracking reaction, and improves the quality and yield of the light oil.

Description

Method and device for co-production of heavy oil lightening and synthesis gas

Technical Field

The invention relates to a method and a device for heavy oil lightening and synthesis gas co-production, belonging to the technical field of petroleum processing.

Background

With the heavy and inferior crude oil, the yield of inferior heavy oil (heavy oil, super heavy oil, oil sand asphalt, vacuum residue oil, oil slurry, deoiled asphalt, etc.) is increased dramatically. The inferior heavy oil generally has the characteristics of low H/C ratio, high contents of sulfur, nitrogen and heavy metals, large carbon residue value and the like, and the coking tendency of the heavy oil in the processing process is serious due to the carbon residue and asphaltene components enriched inside. Due to the problems of catalyst deactivation, high hydrogen consumption, long-period operation and the like, the direct processing and treatment requirements of a large amount of inferior heavy oil are difficult to meet by directly adopting means such as catalytic cracking or catalytic hydrogenation. The inferior heavy oil is processed by adopting the combination of technologies such as solvent deasphalting, visbreaking, catalytic cracking, hydrotreating and delayed coking, and the like, and compared with a one-step heavy oil processing technology, the method has the advantages of longer overall process flow and higher investment cost.

The delayed coking process is used as an inferior heavy oil processing technology widely applied at present, and has the problems of furnace tube coking, large environmental protection pressure in a decoking process, low liquid yield and the like. In addition, a large amount of solid coke is produced as a byproduct in the delayed coking process, particularly high-sulfur coke has low value, and the latest environment-friendly requirement is to take factory-limiting measures on the high-sulfur coke with the sulfur content of more than 3%. In some domestic refineries, petroleum coke generated by delayed coking is used for a circulating fluidized bed combustion power generation or gasification poly-generation process, so that the conversion and utilization of coke are realized. Heavy oil is firstly converted into low-activity petroleum coke, and then the petroleum coke is converted by cooling, grinding and reheating, but the overall process flow is complex and the efficiency is low.

In addition, because the poor heavy oil raw material has a low H/C atomic ratio, the light oil product can be produced to the maximum extent only through the hydrogenation process, and the quality requirement of clean oil products is met, so that the problem of hydrogen source shortage in the process of processing the poor heavy oil in a refinery is more prominent, and hydrogen generated in the technical processes of catalytic reforming and the like is not enough to meet the hydrogen requirement of clean oil product production. Although the direct gasification of inferior heavy oil can directly convert heavy oil into small molecules such as synthesis gas, the oil gas molecules and hydrogen elements existing in the heavy oil are not fully utilized, and the resource waste of the heavy oil is also caused to a certain extent.

In response to the above problems, many researchers have proposed a corresponding short-flow technical solution for conversion of inferior heavy oil processing. One of the processes developed by Exxon is the flexicoking series using fluidized coke powder as the bed material for heavy oil cracking reaction.

The flexible coking process takes coke powder as a heat carrier for heavy oil cracking reaction, and the generated coke is attached to the surface of the coke powder and is conveyed to a gasification/combustion reactor to be removed, so that the coke materials in the reaction need to be returned among reactors such as coking, combustion, gasification and the like, the difficulty in returning the coke powder materials among a plurality of reactors is increased, and the energy consumption of the cracking reaction is increased.

Disclosure of Invention

The invention provides a method for heavy oil lightening and synthesis gas co-production, which optimizes a circulation path of coke generated in a cracking reaction of a heavy oil raw material, improves the utilization value of the coke, reduces the energy consumption of the cracking reaction, improves the quality and yield of light oil, and reduces the difficulty of process operation.

The invention also provides a device for realizing the method.

In order to achieve the above objects, in one aspect, the present invention provides a method for the heavy oil lightening and the synthesis gas co-production, which uses a pyrolysis-coke gasification coupled reaction system having a pyrolysis section and a coke burning section that are communicated with each other through a downer system and coupled with a gasification reactor, the method comprising:

heavy oil raw materials enter a cracking section at the upper part of the coupling reactor and contact with fluidized coke powder to carry out cracking reaction to generate light oil gas and coke powder particles; the coke powder particles descend through the material descending system and enter a coking section at the lower part of the coupling reactor for coking treatment, the coke powder particles which are not completely coked in the coking section are divided into two parts, one part of the coke powder particles are discharged out of the coupling reactor and return to the cracking section to participate in cracking of the heavy oil raw material, and the other part of the coke powder particles are conveyed to the gasification reactor to generate gasification reaction to generate synthesis gas;

introducing part of the synthesis gas from the gasification reactor into the cracking section through the lower part of the cracking section, ascending to the top of the cracking section, combining with the light oil gas, carrying out oil gas-gas separation treatment, carrying out oil gas fractionation on a purified oil gas product output by the oil gas-gas separation treatment, and collecting light oil and synthesis gas products;

and conveying the incompletely gasified coke powder particles in the gasification reactor back to the cracking section to participate in cracking of the heavy oil raw material, or conveying the incompletely gasified coke powder particles back to the coking section to perform the coking treatment.

The method as described above, wherein the flue gas generated by the coking treatment is subjected to a flue gas-solid separation treatment, and the separated coke breeze particles are returned to the coking section.

The method as described above, wherein the conditions of the cleavage reaction are: the reaction temperature is 450 ℃ and 700 ℃, the reaction pressure is 0.1-6.0Mpa, the reaction time is 1-20s, the apparent gas velocity is 1-20m/s, and the catalyst-oil ratio is 4-20.

The method as described above, wherein the conditions of the scorch treatment are: the scorching temperature is 600-.

The method as described above, wherein the gasification reaction conditions are: the reaction temperature is 850 ℃ and 1200 ℃, the reaction pressure is 0.1-6.0Mpa, the apparent gas velocity is 0.1-5.0m/s, and the retention time of coke powder particles is 1-20 min.

The method as described above, wherein before the coke powder particles in the cracking section descend into the coking section, the method further comprises the step of descending the coke powder particles in the cracking section and sequentially carrying out steam stripping treatment and particle size refining treatment.

The method as described above, wherein the steam stripping treatment conditions are: the mass ratio of the water vapor to the heavy oil raw material is 0.1-0.3, the temperature of the water vapor is 200-400 ℃, and the apparent gas velocity of the water vapor is 0.5-5.0 m/s.

The method further comprises the step of cooling and washing the synthesis gas and the light oil gas before the synthesis gas and the light oil gas are combined for the flue gas-solid separation treatment.

In another aspect, the present invention provides an apparatus for heavy oil upgrading and syngas co-production for carrying out any one of the above methods, the apparatus comprising a pyrolysis-coke gasification coupled reaction system consisting of a coupled reactor of a pyrolysis section and a coke burning section, which are communicated with each other through a downer system, and a gasification reactor, wherein:

the coupling reactor comprises a cracking section and a burning section which are mutually communicated through a material descending system, the bottom of the cracking section is communicated with an inlet of the material descending system, an outlet of the material descending system is communicated with the top of the burning section, and an outlet of the material descending system is provided with a one-way plug valve; the cracking section is provided with a heavy oil raw material inlet, an unfired coke particle inlet and a synthesis gas inlet, and the upper part of the cracking section is provided with an oil gas outlet; the coke burning section is provided with a flue gas outlet, a first unburnt particle outlet and a second unburnt particle outlet, and the first unburnt particle outlet is communicated with the unburnt particle inlet through an external conveying pipeline;

the coupling reactor also comprises an oil gas-solid separation section which is arranged at the upper part of the cracking section, and a gas phase outlet of the oil gas-solid separation section is communicated with the oil gas outlet;

the gasification reactor is provided with a particle inlet to be gasified, an unvaporized coke powder particle outlet and a synthesis gas outlet, the particle inlet to be gasified is communicated with the second unburnt coke particle outlet, the unvaporized particle outlet is communicated to the coking section or the cracking section, and the synthesis gas outlet is communicated with the synthesis gas inlet.

The device as described above, wherein the coupling reactor further comprises a flue gas-solid separation section, the flue gas-solid separation section is located between the material lowering system and the coking section, a solid phase outlet of the flue gas-solid separation section is communicated with the coking section, and a gas phase outlet of the flue gas-solid separation section is communicated with the flue gas outlet.

The implementation of the invention has at least the following advantages:

1. the invention fully exerts the synergistic effect among three reactions of heavy oil cracking, coke burning and coke gasification. On one hand, coke generated in the cracking process is used as a reaction raw material of the gasification reactor to generate high-quality synthesis gas after being partially combusted and heated, so that petroleum coke is prevented from being generated, and the hydrogen source of a refinery is enriched; on the other hand, coke powder particles which are not completely gasified in the gasification reactor finally enter the cracking section to contact with the heavy raw oil, so that heat is provided for cracking, meanwhile, a part of the synthesis gas generated by gasification enters the bottom of the cracking section, so that heat is provided for cracking the heavy raw oil in the cracking section, and hydrogen atmosphere is provided for cracking reaction. Therefore, the invention realizes the technical advantages of mutual material supply, energy complementation, synergistic reaction, oil-gas co-production and the like among the three reactions.

2. According to the processing device for heavy oil lightening-coproduction synthesis gas, the heavy oil cracking section, the coking section and the gasification reactor are coupled in the same reaction system, so that the problems of difficult cyclic operation, complex process, large occupied area, high investment and the like among a plurality of reactors in the process of flexible coking and the like are solved, the energy efficiency is further improved, and the technical economy of the method is improved.

Drawings

Fig. 1 is a schematic diagram of an apparatus for heavy oil upgrading and syngas co-production according to an embodiment of the present invention;

fig. 2 is a schematic diagram of an apparatus for heavy oil upgrading and syngas co-production according to another embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a method for heavy oil lightening and synthesis gas co-production, which adopts a coupling reactor internally provided with a cracking section and a burning section which are mutually communicated through a material lowering system and a cracking-coke gasification coupling reaction system coupled with a gasification reactor, and comprises the following steps:

heavy oil raw materials enter a cracking section at the upper part of the coupling reactor and contact with fluidized coke powder to carry out cracking reaction to generate light oil gas and coke powder particles; the coke powder particles descend through the material descending system and enter a coking section at the lower part of the coupling reactor for coking treatment, the coke powder particles which are not completely coked in the coking section are divided into two parts, one part of the coke powder particles are discharged out of the coupling reactor and return to the cracking section to participate in cracking of the heavy oil raw material, and the other part of the coke powder particles are conveyed to the gasification reactor to generate gasification reaction to generate synthesis gas; introducing part of the synthesis gas from the gasification reactor into the cracking section through the lower part of the cracking section, ascending to the top of the cracking section, combining with the light oil gas, carrying out oil gas-gas separation treatment, carrying out oil gas fractionation on a purified oil gas product output by the oil gas-gas separation treatment, and collecting light oil and synthesis gas products; and conveying the incompletely gasified coke powder particles in the gasification reactor back to the cracking section to participate in cracking of the heavy oil raw material, or conveying the incompletely gasified coke powder particles back to the coking section to perform the coking treatment.

The coupling reactor of the invention is an integrated coupling reactor which can simultaneously carry out cracking reaction and scorching treatment, and the cracking section is positioned at the lower part of the scorching section. The pyrolysis section on upper portion is through falling the coupling of material system and the burning section of lower part, should fall the material system and not only can make the fine coke granule in the pyrolysis section fall into down in the burning section, more can realize the effective isolation of two reactions of pyrolysis and burning, guarantees independent reaction environment separately, avoids the adhesion and the reunion between the fine coke granule to improve the security and the stability of whole technology.

The material dropping system can be a high-temperature-resistant material dropping pipe, coke powder particles with larger particle sizes in the cracking section can enter the coking section downwards, a one-way plug valve can be arranged at the lower end of the material dropping pipe, and the one-way plug valve can be opened after the coke powder particles entering the material dropping pipe reach a certain number, so that one-way transmission from the cracking section to the coking section is ensured.

In the method, the heavy oil raw material enters a cracking section through a heavy oil raw material inlet in a coupling reactor, and contacts with fluidized coke powder in the cracking section to perform cracking reaction to generate light oil gas and coke powder particles, wherein the coke powder particles are particles formed by coke aggregation and adhesion on the surface of the coke powder. In order to increase the contact area between the heavy oil raw material and the fluidized coke powder, an atomization device can be arranged at the raw material inlet to atomize the heavy oil raw material and then contact the heavy oil raw material with the fluidized coke powder to generate cracking reaction.

Coke powder particles with serious coking and larger particle size in the cracking section descend in the cracking section and enter a coking section through a material descending system, the coking treatment is carried out in the coking section to generate high-temperature flue gas, the high-temperature flue gas can be subjected to gas-solid separation, the flue gas after the gas-solid separation is collected to recover heat, and the coke powder particles obtained by the gas-solid separation can return to the coking section; the coke powder particles which are not fully combusted in the coke burning section can be divided into two parts to carry out subsequent different reactions.

Specifically, a part of coke breeze particles which are not fully combusted in the coking section carry heat to be output from the coupling reactor, and are lifted and returned to the cracking section through an external conveying pipeline, so that the coke breeze particles serve as reaction bed materials and heat supply bodies for the cracking section and continuously participate in cracking of the heavy oil raw materials; the other part of coke powder particles which are not fully combusted in the coke burning section are driven by air in the coke burning section to carry heat and are input into the gasification reactor through the outside of the coupling reactor, and are subjected to gasification reaction with a gasification agent in the gasification reactor to generate synthesis gas containing active small molecules such as hydrogen, carbon monoxide and the like, and the carried heat can also be used as energy compensation of the gasification reaction.

As the syngas is output from the gasification reactor, a portion of the output syngas may be collected and the remainder of the syngas may be input into the cracking section from a lower portion of the cracking section via an exterior of the coupled reactor. The synthesis gas input to the cracking section can provide heat required by cracking reaction, so that the heat of the cracking-gasification reaction zones is utilized in a matching manner, the overall energy efficiency is improved, and on the other hand, the hydrogen in the synthesis gas can inhibit the coking reaction causing the heavy oil cracking reaction to a certain extent, so that the product distribution of the heavy oil cracking is improved, and the quality and the yield of oil gas are improved. And the synthesis gas also fully fluidizes the coke breeze particles in the cracking section.

In addition, the light oil gas in the cracking section can be combined with the synthesis gas, so that in order to avoid the collected light oil gas and the synthesis gas from carrying coke powder particles, the combined material flow of the light oil gas and the synthesis gas can be subjected to oil-gas-solid separation treatment, purified oil gas products output after the oil-gas-solid separation are collected, and the purified oil gas products are subjected to oil-gas fractionation and other means to obtain gas products such as synthesis gas products, dry gas, liquefied gas and the like, light oil and possibly heavy oil products. Wherein the light oil can be further cut to obtain liquid products with different distillation ranges, and the heavy oil product can be returned to the cracking section for recycling processing; the coke powder particles output after the oil gas-gas solid separation can be recovered and recycled, for example, the coke powder particles are returned to the cracking section to participate in the cracking reaction again, so that the use efficiency of the coke powder particles is further increased, and the processing cost of heavy oil weight conversion is reduced.

In the gasification reactor, part of coke powder particles which are not completely gasified can be remained, the part of coke powder particles can return to the cracking section, can be used as a cracking reaction bed material to continuously participate in the cracking reaction, and can also provide heat for the cracking reaction so as to further reduce the energy consumption of the cracking reaction, and it can be understood that when the part of coke powder particles which are not completely gasified enter the cracking section, besides the cracking reaction, part of coke powder particles with large particle size can also fall into the coke burning section through the material reducing system to be burnt; or, the part of the incompletely gasified coke powder particles can also return to the coking section for coking treatment, and it can be understood that when the part of the incompletely gasified coke powder particles enter the coking section, besides the coking treatment, the part of the incompletely coked coke powder particles can also be lifted and returned to the cracking section through an external conveying pipeline.

The invention utilizes the upper cracking-lower burning coupling reactor to crack the heavy oil raw material, provides a more convenient path for the reciprocating cyclic utilization of coke powder particles, not only leads the coke powder particles at the cracking section to be burnt in the burning section to directly decompose the heat supply for a heat exchange network, but also leads the incompletely burnt coke powder particles to carry heat to respectively return to the cracking section and the gasification reactor to be used as bed materials of cracking reaction and raw materials of gasification reaction; meanwhile, part of the synthesis gas carrying heat in the gasification reactor can also enter the cracking section, so that reaction heat is provided for the cracking reaction, a hydrogen atmosphere is provided for the cracking reaction, and coke formation of the cracking reaction is inhibited, thereby being beneficial to improving the quality and yield of oil gas.

In addition, the coke powder particles which do not participate in the gasification reaction in the gasification reactor can be continuously recycled, and when the coke powder particles which are not completely gasified are driven by the gasification agent in the gasification reactor to return to the cracking section, the coke powder particles can be used as a reaction bed material and a heat supply party to continuously participate in the cracking reaction, so that the overall energy consumption is reduced, and the process flow is simplified; when coke powder particles which are not completely gasified are driven by a gasification agent in the gasification reactor to return to the coking section, the coking treatment can be continuously carried out, and part of coke powder particles in the coking section can also carry heat to downwards enter the cracking section to participate in the cracking reaction.

The invention can form mutual supply and heat complementation of raw materials among cracking, charring and gasification in one system, and realizes the technical advantages of reaction cooperative coupling, oil-gas co-production and the like. The entire coupled reactor can be operated at high pressure, thereby greatly increasing processing capacity and achieving upgrading of high quality syngas to heavy oil cracking processes at high pressure.

Furthermore, before the coke powder particles in the cracking section descend through the material descending system and enter the coke burning section, the method also comprises the step of sequentially carrying out steam stripping treatment and particle size refining treatment on the coke powder particles in the cracking section in the descending process of the cracking section.

Specifically, a steam stripping section and a particle size refining section can be arranged at the lower part of the cracking section of the coupling reactor and are used for sequentially carrying out steam stripping and particle size refining on coke breeze particles descending from the cracking section. The steam stripping can clear oil gas on the surfaces of descending coke powder particles, and the particle size refinement can cut and refine the particle size of the coke powder particles subjected to steam stripping, so that the coke powder particles are prevented from being bonded and agglomerated. Generally, the particle size of the coke powder particles after steam stripping is 10-500 μm. After the coke powder particles are subjected to steam stripping treatment and particle size refining treatment in sequence, the coke powder particles fall into a coking section through a material dropping system for coking treatment.

And because a steam stripping section and a particle size refining section are also arranged between the cracking section and the coking section, relatively independent reaction environments of the cracking section and the coking section can be ensured, and the safety and the operation stability of the coupling reaction are ensured.

In particular implementations, the steam stripping section may include a multi-layer stripping configuration to remove light oil and gas from the surface of the coke particles by the action of stripping steam entering through a stripping steam inlet. In detail, the multi-layer stripping structure can adopt one or more combinations of herringbone baffles, annular baffles, conical baffles, grid baffles, bulk packing or structured packing and the like.

The particle size refines the section and can include the jet mill, and the jet mill is used for utilizing the vapor that gets into from grinding the vapor entry to carry out crushing and screening to the coke granule after the steam strip section is handled to guarantee that the coke granule that gets into the gasification section can have bigger area of contact with the gasification agent, guarantee that gasification reaction's high efficiency goes on.

It will be appreciated that the steam stripping section is provided with a stripping steam inlet and the particle size refining section is provided with a grinding steam inlet.

After the coke powder particles are subjected to the coking treatment in the coking section, part of the coke powder particles which do not participate in the coking treatment are output from the lower part of the coking section to the coupling reactor and respectively enter the cracking section and the gasification reactor under the driving of air entering the coking section.

Further, before the gas-solid separation treatment is carried out on the combined material flow of the light oil gas and the synthesis gas, the combined material flow can be subjected to cooling washing treatment, so that the combined material flow is subjected to the gas-solid separation treatment after being treated by the low-temperature liquid medium. The cooling washing treatment can clear away some fine coke particles in the combined material flow on the one hand, and the fine coke particles that make clear away fall back to the schizolysis section and continue to act as the schizolysis carrier, and on the other hand can cool down combined material flow, avoids light oil gas wherein to continue to produce coke with high temperature state in gas-solid separation processing to further improve the quality of light oil, also avoided producing coke too much and caused the jam to gas-solid separation system.

In particular, the reduced temperature washing may be performed in a reduced temperature washing section. The cooling washing section can adopt a built-in filler type structure to strengthen the contact between the mixed material flow and the low-temperature liquid, and can also adopt a tower plate type structure to strengthen the contact between the mixed material flow and the low-temperature liquid.

The built-in packing structure can comprise loose packing such as Raschig rings, pall rings, step rings, arc saddle packing, intalox saddle packing, metal ring intalox saddle, spherical packing and the like, or a combination of more than one of regular packing such as grid packing, corrugated packing, pulse packing and the like.

The tower plate structure comprises one or more of bubble cap tower plate, sieve pore tower plate, floating valve tower plate, jet tower plate and flow-through tower plate.

The cryogenic liquid may be a heavy oil feedstock. In the actual operation process, the heavy oil raw material enters the cracking section in two paths, one path of heavy oil raw material directly contacts with the coke powder to perform cracking reaction, the other path of heavy oil raw material is used as low-temperature liquid and firstly passes through the washing section to perform heat exchange, and then goes downwards to perform cracking reaction with the coke powder, so that the energy consumption required by the cracking reaction is effectively reduced. In the present invention, the heavy oil feedstock as the low-temperature liquid is 5 to 10% by mass of the total mass of the heavy oil feedstock.

Meanwhile, in order to improve the utilization rate of the coke powder particles, the coke powder particles which do not participate in the coke burning treatment in the coke burning section can enter the cracking section after being subjected to bulk separation, so that the coke powder particles can be uniformly distributed in the cracking section, and the cracking reaction efficiency is improved.

The invention also limits the process parameters in the coupling reactor as follows, thereby further realizing the matching of material flow and energy flow in the heavy oil processing process, ensuring the stability in the whole heavy oil processing process and improving the overall energy efficiency.

The cracking reaction conditions are as follows: the reaction temperature is 450 ℃ and 700 ℃, the reaction pressure is 0.1-6.0Mpa, the reaction time is 1-20s, the apparent gas velocity is 1-20m/s, and the catalyst-oil ratio is 4-20. In general, heavy oil is preheated to the temperature of 220 ℃ and 300 ℃ and then enters a cracking section for reaction. Wherein the superficial gas velocity refers to the superficial gas velocity of the synthesis gas and the set of fluidizing gases used to fluidize the coke breeze particles.

The conditions of the scorch treatment were: the scorching temperature is 600-. This reaction condition can guarantee that coking treatment goes on smoothly to can carry out rational distribution to the fine coke granule that gets into in the coker, make partial fine coke granule can not take place complete combustion and can get into gasification reactor and pyrolysis section, thereby help going on of gasification reaction and pyrolysis, guarantee the stability of whole flow. Wherein, the air velocity refers to the air velocity of the air entering the coking device and participating in the coke burning treatment.

The gasification reaction conditions are as follows: the reaction temperature is 850 ℃ and 1200 ℃, the reaction pressure is 0.1-6.0Mpa, the apparent gas velocity is 0.1-5.0m/s, and the retention time of coke powder particles is 1-20 min. The reaction conditions can ensure the smooth proceeding of the gasification reaction, and are favorable for reasonably distributing coke powder particles in the gasification reactor, thereby ensuring the stability of the whole process. Wherein the superficial gas velocity refers to the superficial gas velocity of the combination of the gasifying agent and the fluidizing gas for fluidizing the coke powder particles, and the residence time of the coke powder particles refers to the residence time of the coke powder particles in the gasification reactor.

The gasification agent can be introduced into the gasification reactor from the outside of the coupling reactor, and specifically, the gasification agent can be one or more of oxygen, water vapor, oxygen-enriched air and air.

Further, in the steam stripping treatment, the mass ratio of the steam to the heavy oil is 0.1-0.3, the temperature of the steam is 200-400 ℃, and the superficial gas velocity of the steam is 0.5-5.0 m/s.

The Conradson carbon residue value of the heavy oil raw material is more than or equal to 8 percent, and the Conradson carbon residue raw material can be a mixture of one or more of heavy oil, super heavy oil, oil sand asphalt, normal pressure heavy oil, vacuum residual oil, catalytic cracking oil slurry and solvent deoiling asphalt in any proportion, and can also be a mixture of one or more of heavy tar and residual oil in the coal pyrolysis or liquefaction process, heavy oil generated by dry distillation of oil shale, low-temperature pyrolysis liquid products in biomass and other derived heavy oils in any proportion.

The coke powder of the present invention may be in the form of microspherical coke powder with excellent fluidizing performance. Generally, the particle size of the coke powder is 10 to 500. mu.m, and further 20 to 200. mu.m.

The invention is explained in detail below with reference to specific embodiments and the accompanying drawings.

Example 1

Fig. 1 is a schematic view of an apparatus for the heavy oil upgrading and synthesis gas co-production according to an embodiment of the present invention, in which the method for the heavy oil upgrading and synthesis gas co-production uses an apparatus as shown in fig. 1, the apparatus includes a pyrolysis-coke gasification coupled reaction system composed of a coupled reactor 100 and a gasification reactor 200 of a pyrolysis section 2 and a coke burning section 3, which are communicated with each other through a material descending system 1, and specifically:

the coupling reactor 100 comprises a cracking section 2 and a coking section 3 which are mutually communicated through a material descending system 1, wherein the bottom of the cracking section 2 is communicated with an inlet of the material descending system 1, an outlet of the material descending system 1 is communicated with the coking section 3, and an outlet of the material descending system 1 is provided with a one-way plug valve; the cracking section 2 is provided with a heavy oil raw material inlet, an unfired coke particle inlet and a synthesis gas inlet, and the upper part of the cracking section is provided with an oil gas outlet; the coke burning section 3 is provided with a flue gas outlet, a first unburnt particle outlet and a second unburnt particle outlet, and the first unburnt particle outlet is communicated with the unburnt particle inlet through an external conveying pipeline 4; the lower part of the coking section 3 is also provided with an unvaporized particle return inlet;

specifically, the coupling reactor 100 may be obtained by appropriately modifying and assembling a cracking reactor and a char-combusting reactor commonly used in the art, and the cracking reactor may be, for example, a fluidized bed reactor, and the bottom end of the cracking reactor and the top end of the char-combusting reactor are communicated with each other through a material descending system. The cracking reactor and the coke burning reactor are preferably coaxially arranged so as to facilitate the transportation and circulation of materials;

wherein, a fluidized bed can be included in the cracking section 2, so that the coke powder and the particles are in a fluidized state through the action of the fluidized bed and serve as carriers of the cracking reaction;

a char-combusting reactor may be included in the char-combusting section 3.

The coupling reactor 100 also comprises an oil gas-solid separation section 5, the oil gas-solid separation section 5 is positioned at the upper part of the cracking section 2, and a gas phase outlet of the oil gas-solid separation section 5 is communicated with the oil gas outlet;

specifically, the oil gas-solid separation section 5 may include an oil gas-solid separator 51, a gas-solid separation inlet of the oil gas-solid separator 51 is communicated with the cracking section 2, and is configured to receive the light oil gas and the synthesis gas of the cracking section 2 to perform gas-solid separation thereon, a gas phase outlet of the oil gas-solid separator 51 is communicated with the oil gas outlet, and a solid phase outlet of the oil gas-solid separator 51 is communicated with the cracking section 2, and is configured to return fine coke particles obtained by gas-solid separation to the cracking section 2 to participate in the cracking reaction. The oil gas-gas solid separator 51 may be, for example, a cyclone separator commonly used in the art.

A gasification reactor 200 having a to-be-gasified particle inlet communicating with the second unfired coke particle discharge port, an unvaporized particle outlet communicating with the unfired coke particle return inlet of the coke burning zone 3, and a syngas outlet communicating with the syngas inlet.

The gasification reactor 200 may include a fluidized bed, the coke powder particles are in a fluidized state under the action of the fluidized bed and contact with a gasifying agent to perform a gasification reaction, the gasification reactor 200 is further provided with a gasifying agent inlet for injecting the gasifying agent and a slag discharge port for outputting impurities such as solid ash and the like which cannot be reacted and converted;

specifically, the syngas outlet is communicated with the syngas outlet conduit to output the syngas from the gasification reactor 200, and a portion of the syngas may be drawn into the cracking section 2 by connecting a branch in communication with the syngas inlet to the syngas outlet conduit.

On the basis of the above, the coupling reactor 100 in fig. 1 further includes:

a steam stripping section 6 located below the pyrolysis section, the steam stripping section 6 may include steam stripping baffles to remove oil and gas from the surface of the coke breeze particles in the downward travel process by injecting steam, and the steam stripping section has an inlet for injecting steam;

a particle size refining section (not shown) located below the steam stripping section 6, which may include a steam jet mill for refining and milling the stripped coke breeze particles by injecting steam, and having an inlet for injecting steam;

the atomizing device 7 is arranged in the cracking section 2, is communicated with the heavy oil raw material inlet, and is used for atomizing the heavy oil raw material, and specifically can be an atomizer;

a dispersing device (not shown) which is arranged in the cracking section 2, is communicated with the unburnt coke particle inlet and is used for dispersing the coke powder particles entering the cracking section 2 from the coking section 3 through an external conveying pipeline;

a cooling washing section 8, wherein the cooling washing section 8 is arranged at the upper part of the cracking section 2, is communicated with the cracking section 2, and is used for cooling and washing a combined stream (a mixture of light oil gas and synthesis gas) which is about to enter the oil gas-gas solid separation section 5;

the flue gas-solid separation section 9 is positioned at the upper part of the coking section 3 and can comprise a flue gas-solid separator 91, such as a cyclone separator commonly used in the field, and is used for carrying out gas-solid separation on the flue gas generated by the coking section 3; the flue gas-solid separator 91 comprises a flue gas inlet, a purified flue gas outlet and a flue gas coke powder particle outlet, wherein the flue gas inlet is used for receiving flue gas of the coking section 3, the purified flue gas outlet is communicated with the flue gas outlet, and the flue gas coke powder particle outlet is communicated with the coking section 3 and is used for returning separated coke powder particles to the coking section 3.

The method for heavy oil lightening and synthesis gas co-production by using the device provided by the embodiment is briefly described as follows:

the fully preheated heavy oil raw material is input into a cracking section in the coupling reactor 100 through a heavy oil raw material inlet, the heavy oil raw material is atomized by the atomization device 7 and then directly contacts with fluidized coke powder (including coke powder particles with coke attached to the outside) to perform cracking reaction, light oil gas and coke are respectively obtained, and the coke can be attached to the surface of the coke powder to form coke powder particles.

Coke powder particles with serious coking and larger particle size can descend under the action of gravity, and in the descending process, light oil gas remained on the surfaces of the coke powder particles is removed through a steam stripping section 6, and then the coke powder particles are cut and refined through a particle size refining section. Finally, the coke powder particles enter the material descending system 1 from the cracking section 2 and fall into the coke burning section 3 through the material descending system 1.

In the coking section 3, the coke powder particles and air introduced into the coking section 3 through a coking gas inlet are combusted at high temperature to generate flue gas, the flue gas enters a flue gas-solid separator 91 in a flue gas-solid separation section 9 for gas-solid separation, purified flue gas output by the flue gas-solid separator 91 is output from a purified flue gas outlet, and can enter a subsequent heat exchange network for flue gas waste heat recovery after being output through a flue gas outlet of the coking section 3, and the coke powder particles output by the flue gas-solid separator 91 are output from a flue gas coke powder particle outlet and enter the coking section 3; the coke powder particles which are not completely combusted in the coke burning section 3 respectively enter the cracking section 2 and the gasification reactor 200 outside the coupling reactor 100, wherein the coke powder particles c entering the cracking section 2 are primary coke powder particles, and the coke powder particles entering the gasification reactor 200 are called secondary coke powder particles.

The coke powder particles which are not completely combusted in the coking section 3 enter the external conveying pipeline 4 through the first unburnt particle discharge port under the driving of the emptying in the coking section 3, and enter the cracking section 2 through the unburnt particle inlet of the cracking section 2 to form primary coke powder particles, the primary coke powder particles can be used as reaction bed materials and continue to contact with heavy oil raw materials to generate cracking reaction, and heat carried by the primary coke powder particles can also provide heat for the cracking reaction, so that the energy consumption of the cracking reaction is reduced.

Under the drive of air, coke powder particles which are not completely combusted in the coke burning section 3 are output from the coupling reactor 100 through a second unfired coke particle outlet and enter the gasification reactor 200 through a particle inlet to be gasified to form secondary coke powder particles, the secondary coke powder particles can be used as reaction raw materials and generate synthesis gas through gasification reaction with a gasification agent in the gasification reactor 200, and heat carried by the secondary coke powder particles can also provide heat for the gasification reaction, so that the energy consumption of the gasification reaction is reduced. As the synthesis gas is generated, the synthesis gas is output from the synthesis gas outlet of the gasification reactor 200, a part of the synthesis gas a1 is collected for use, and a part of the synthesis gas a2 enters the cracking section 2 to provide reaction heat and reaction atmosphere for the cracking reaction of the heavy oil raw material.

And the synthesis gas a2 is mixed with light oil gas, then is cooled and washed by the cooling washing section 8, enters the oil gas-solid separator 51 through the gas-solid separation inlet of the oil gas-solid separator 51 in the oil gas-solid separation section 5 for gas-solid separation treatment, and the obtained purified oil gas product is output and coupled to the reactor 100 through the oil gas outlet, so that the synthesis gas, dry gas, liquefied gas and other gas products and light oil products can be respectively obtained through a gas-liquid fractionating tower, an oil gas absorption stabilizing tower and other systems. Of course, the oil product can be further cut and separated to obtain liquid products with different distillation range components, wherein heavy oil (possibly including part of contact agent solid particles) can be mixed with heavy oil raw materials for recycling processing; the coke powder particles separated by the oil gas-gas solid separator 51 can be output to the cracking section 2 from the solid phase outlet of the oil gas-gas solid separator 51.

And part of the incompletely gasified coke powder particles are also arranged in the gasification reactor 200, the part of the incompletely gasified coke powder particles are output out of the gasification reactor 200 through an unvaporized particle outlet and return to the inlet through the unvaporized particles to enter the coke burning section 3, and reaction raw materials and certain heat are provided for coke burning treatment.

The conditions of the cracking reaction are as follows: the reaction temperature is 450 ℃ and 700 ℃, the reaction pressure is 0.1-6.0Mpa, the reaction time is 1-20s, the apparent gas velocity is 1-20m/s, and the agent-oil ratio is 4-20;

the conditions of the above gasification reaction are: the reaction temperature is 850 ℃ and 1200 ℃, the reaction pressure is 0.1-6.0Mpa, the apparent gas velocity is 0.1-5.0m/s, and the retention time of coke powder particles is 1-20 min.

The conditions of the above-mentioned scorch treatment are: the scorching temperature is 600-.

The conditions of the steam stripping treatment are as follows: the mass ratio of the water vapor to the heavy oil is 0.1-0.3, the temperature of the water vapor is 200-400 ℃, and the apparent gas velocity of the water vapor is 0.5-5.0 m/s.

In order to verify the effect of the invention, the Liaohe normal pressure heavy oil is tested by adopting the device and the process flow shown in figure 1.

Table 1 shows the properties of the heavy oil feedstock. Table 2 shows specific reaction parameters, and compared with the conventional heavy oil cracking process, the method of this embodiment can improve the yield of light oil, improve the yield of liquid, significantly reduce the yields of dry gas and coke, and show detailed product distribution in tables 3 and 4.

TABLE 1

Sample name	Liaohe atmospheric heavy oil
		Density (20 ℃ C.)/g-cm^-3	0.9817
Kinematic viscosity (100 ℃ C.)/mm²·s^-1	314.8
		Conradson carbon residue/wt%	13.39
C/wt％	86.8
		H/wt％	11.58
S/wt％	0.39
		N/wt％	0.81
n(H)/n(C)	1.59
		Saturated fraction/wt%	31.08
The fragrance is divided by weight%	26.13
		Colloid/wt%	40.06
Asphaltenes/wt%	2.73
		Ni/ppm	88
V/ppm	2.16
		Initial boiling point	360
10％	399
		30％	446
50％	482
		70％	542
90％	628
		End point of distillation	692
VGO proportion (350-	56.62％
		Heavy oil fraction ratio (>500℃)	43.38％

As can be seen from Table 1: the Liaohe normal pressure heavy oil has a carbon residue value of more than 13%, a lower H/C atomic ratio and a higher density. In addition, the high asphaltene content and the high heavy component content of greater than 500 ℃ in the heavy oil feedstock means that the heavy oil feedstock has a severe propensity to coke during cracking.

TABLE 2

TABLE 3

Sample name/wt%	Liaohe atmospheric heavy oil
		Yield of dry gas	4.14
Yield of liquefied gas	1.28
		Gasoline fraction	2.87
Diesel oil fraction	7.21
		Vacuum distillate	40.12
Heavy oil fraction	31.85
		Coke yield	12.53

As can be seen from Table 3:

1. the method and the device of the embodiment can obviously improve the yield of the light oil and inhibit the generation of coke;

2. the coke yield to carbon residue ratio is about 0.8 to 0.9, much less than the coke/carbon residue ratio of 1.4 to 1.6 in delayed coking, compared to the initial carbon residue value of the feedstock. The liquid quality yield is kept between 70 and 80 percent, and the heavy oil fraction with the temperature of more than 500 ℃ is contained in the liquid, and can be processed in a recycling mode.

TABLE 4

Synthesis gas Components	H₂	CO	CO₂	CH₄Etc. other components
					Volume content (vol%)	40.9	37.6	19.9	1.6

As can be seen from Table 4: the synthesis gas obtained in this example was H₂The sum of the volume fraction of the carbon dioxide and the CO is about 80 percent, and the carbon dioxide can be used as high-quality synthesis gas for subsequent processes of hydrogen production by reforming or F-T synthesis of oil products and the like.

Example 2

Fig. 2 is a schematic view of an apparatus for upgrading heavy oil and co-producing synthesis gas according to another embodiment of the present invention, and the method for upgrading heavy oil and co-producing synthesis gas according to the embodiment uses the apparatus shown in fig. 2. Unlike the apparatus of example 1, the apparatus of this example has the non-gasified particle return inlet at the lower portion of cracking section 2.

The method for heavy oil lightening and synthesis gas co-production using the apparatus provided in this embodiment is different from the method in embodiment 1 in that part of the incompletely gasified coke breeze particles in the gasification reactor 200 are output from the gasification reactor 200 through the unvaporized particle outlet, and return to the cracking section 2 through the unvaporized particles, so as to provide a reaction bed material and a certain amount of heat for the cracking reaction.

To verify the effect of the present invention, the Liaohe atmospheric heavy oil of example 1 was tested using the apparatus and process flow shown in FIG. 2.

Specific reaction parameters and examples1, compared with the conventional heavy oil cracking process, the method in the embodiment can keep the liquid mass yield between 70 and 80 percent and obtain H in the synthesis gas₂The sum of the volume fraction and the CO is about 80 percent.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for the heavy oil lightening and the synthesis gas co-production is characterized in that a cracking-coke gasification coupling reaction system which is internally provided with a cracking section and a coke burning section which are communicated with each other through a material descending system and is coupled with a gasification reactor is adopted, and the method comprises the following steps:

2. The method as claimed in claim 1, wherein the flue gas generated by the burning treatment is subjected to a flue gas-solid separation treatment, and the separated coke breeze particles are returned to the burning section.

3. The method according to claim 1, characterized in that the conditions of the cleavage reaction are: the reaction temperature is 450 ℃ and 700 ℃, the reaction pressure is 0.1-6.0Mpa, the reaction time is 1-20s, the apparent gas velocity is 1-20m/s, and the catalyst-oil ratio is 4-20.

4. The method according to claim 1, wherein the conditions of the scorch treatment are: the scorching temperature is 600-.

5. The method of claim 1, wherein the gasification reaction conditions are: the reaction temperature is 850 ℃ and 1200 ℃, the reaction pressure is 0.1-6.0Mpa, the apparent gas velocity is 0.1-5.0m/s, and the retention time of coke powder particles is 1-20 min.

6. The process of any one of claims 1 to 5, wherein the coke fines particles in the pyrolysis section are further subjected to steam stripping and size reduction in the pyrolysis section prior to descending into the coking section.

7. The method according to claim 6, characterized in that the conditions of the steam stripping treatment are: the mass ratio of the water vapor to the heavy oil raw material is 0.1-0.3, the temperature of the water vapor is 200-400 ℃, and the apparent gas velocity of the water vapor is 0.5-5.0 m/s.

8. The method according to any one of claims 1 to 7, wherein before the synthesis gas and the light oil gas are combined for the oil gas-gas solid separation treatment, the method further comprises a cooling washing treatment of the synthesis gas and the light oil gas.

9. An apparatus for the co-production of heavy oil lightening and synthesis gas for carrying out the method according to any one of claims 1 to 8, wherein the apparatus comprises a pyrolysis-coke gasification coupled reaction system consisting of a coupled reactor of a pyrolysis section and a coke burning section, which are communicated with each other through a downer system, and a gasification reactor, wherein:

10. The device of claim 9, further comprising a flue gas-solid separation section in the coupling reactor, wherein the flue gas-solid separation section is located between the material descending system and the coking section, a solid phase outlet of the flue gas-solid separation section is communicated with the coking section, and a gas phase outlet of the flue gas-solid separation section is communicated with the flue gas outlet.