CN112723969A

CN112723969A - Method for producing ethylene, propylene and aromatic hydrocarbon and catalytic conversion device

Info

Publication number: CN112723969A
Application number: CN201910974659.XA
Authority: CN
Inventors: 张执刚; 魏晓丽; 龚剑洪; 张策; 崔琰; 刘宪龙
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2019-10-14
Filing date: 2019-10-14
Publication date: 2021-04-30
Anticipated expiration: 2039-10-14
Also published as: CN112723969B

Abstract

A method for producing ethylene, propylene and aromatic hydrocarbon and a catalytic conversion device are disclosed, heavy oil contacts with a first strand of catalyst from a regenerator in a first reactor to generate an oil gas and catalyst mixture, one part of separated carbon four components and four external carbon components contact with a second strand of regenerated catalyst from the regenerator in a second reactor to generate the oil gas and catalyst mixture, the rest carbon four components enter an aromatization reactor, and a reaction product of the aromatization reactor is separated by a second separation system to obtain dry gas, liquefied gas and gasoline rich in aromatic hydrocarbon, so that ethylene, propylene and aromatic hydrocarbon products are further separated. The method and the device provided by the invention solve the problem of alkane accumulation in the carbon four-cycle, can greatly increase the yields of ethylene, propylene and aromatic hydrocarbon, and simultaneously greatly reduce the energy consumption and the operation cost of the carbon four-cycle.

Description

Method for producing ethylene, propylene and aromatic hydrocarbon and catalytic conversion device

Technical Field

The invention relates to a method and a device for producing chemical raw materials from petroleum raw materials, in particular to a method and a device for producing ethylene, propylene and aromatic hydrocarbon from heavy oil.

Technical Field

Ethylene, propylene and BTX aromatics are growing in demand each year as a large group of basic chemical feedstocks. The catalytic cracking is used as a device for processing heavy oil to produce gasoline, and a large amount of propylene is also produced as a byproduct, so that the catalytic cracking is a main supplement source of the propylene market. Wherein, the deep catalytic cracking (such as DCC process) using more selective molecular sieve (ZSM-5) as an active center can produce propylene in large quantity and produce certain propylene and BTX aromatic hydrocarbon as byproducts. At present, wax oil or hydrogenated wax oil is generally adopted in the process, and a small amount of residual oil or paraffin-based atmospheric residual oil is mixed as a raw material.

The technology for preparing propylene from liquefied gas rich in olefin takes liquefied gas with lower added value as raw material, and the carbon tetraolefin in the liquefied gas is cracked under the action of catalyst to generate propylene and ethylene with high added value and aromatic hydrocarbon-rich gasoline component with high octane value, for example, in the DCC family technology, C4 olefin is returned to a catalytic cracking device for cyclic cracking to generate ethylene and propylene. Meanwhile, ethanol gasoline is popularized nationwide in 2020, so that etherified C4 or etherified light gasoline products are limited to be added into finished gasoline, a large number of C4 etherifying devices are idle, and reprocessing and utilization of C4 olefins are concerned.

CN104878A discloses a method for producing low-carbon olefin, which takes gasoline, kerosene, diesel oil, vacuum wax oil, residual oil and mixture as raw materials, and uses Y-shaped molecular sieve andZSM-5 molecular sieve is used as an active center; a fluidized bed or a moving bed reactor is adopted; the operating conditions are that the pressure is 150 kPa-300 kPa, the reaction temperature is 550 ℃ and 650 ℃, and the space velocity is 0.2-20hr^-1And the agent-oil ratio is 2-12. The method has high reaction temperature, more methane byproducts and large amount of unusable carbon four and diesel oil.

CN1034586A discloses a method for producing low-carbon olefin by hydrocarbon oil, which takes gasoline, kerosene, diesel oil, vacuum wax oil, residual oil and a mixture as raw materials, and takes a Y-shaped molecular sieve and a phosphorus-containing ZSM-5 molecular sieve as active centers; a fluidized bed or a riser reactor is adopted; the operation conditions are that the pressure is 120 kPa-400 kPa, the reaction temperature is 480 ℃ and 680 ℃, the residence time is 0.1-6 seconds, the agent-oil ratio is 4-20, and the atomized water vapor accounts for 1-50 percent of the weight of the raw materials. This method, despite modifying the catalyst, has similar problems to CN104878, i.e. high reaction temperature, more methane by-product, and generation of large amount of unusable carbon four and diesel.

CN1056595A discloses a method for producing carbon olefin by using multi-stage feeding from ethane to residual oil as raw material. The method uses a molecular sieve containing alkaline earth metal as an active center; a riser reactor is adopted; the operation conditions are that the pressure is 130 kPa-400 kPa, the reaction temperature is 600-900 ℃, the residence time is 0.1-6 seconds and the catalyst-oil ratio is 5-100, and the multi-stage feeding cracking is carried out from high to low according to different cracking difficulties. Although the method solves the problem of byproducts such as carbon four, the method also has the problem of more byproducts such as methane and coke for raw materials with poor processing property,

CN1065963A discloses a method for producing low-carbon olefin by hydrocarbon oil multi-stage feeding, which takes gasoline, vacuum wax oil and residual oil as raw materials and takes a Y-shaped molecular sieve and a ZSM-5 molecular sieve as active centers; adopting a riser reactor and a fluidized bed reactor; the operating conditions are that the pressure is 130 kPa-400 kPa, the reaction temperature is 500-600 ℃, the riser residence time is 1-5 seconds, and the space velocity of the fluidized bed is 0.2-20hr^-1And the agent-oil ratio is 6-15, the atomized water vapor accounts for 1-60% of the weight of the raw material, wherein the mixture of the vacuum wax oil and the residual oil enters the bottom of the riser reactor, the gasoline component enters the fluidized bed reactor, and the riser reactor and the fluidized bed reactor are connected in series. The method cannot solve the problem of nailAlkane, carbon four and diesel byproducts are more problems.

CN102337148A discloses a method for producing low-carbon olefins by using gasoline rich in four to eight carbon atoms as a raw material. The method uses a Y-type molecular sieve and a ZSM-5 molecular sieve as active centers; adopting a riser reactor and a fluidized bed reactor; the operating conditions are that the pressure is 150 kPa-300 kPa, the reaction temperature is 480-^-1And the agent-oil ratio is 8-40. The method cannot solve the problem of accumulation of alkane components despite cyclic utilization of four-carbon to eight-carbon olefins.

CN101362961A discloses a method for producing low-carbon olefin and aromatic hydrocarbon by using hydrocarbons with the temperature of 160-270 ℃ as raw materials. The method uses a Y-type molecular sieve and a ZSM-5 molecular sieve as active centers; a riser reactor or a fluidized bed reactor is adopted; the operating conditions are that the pressure is 100 kPa-1000 kPa, the reaction temperature is 450 ℃ and 750 ℃, and the space velocity is 1-150hr^-1And the agent-oil ratio is 1-150. The method solves the problem of the export of part of diesel oil.

CN101747928A discloses a method for producing low-carbon olefins and aromatics from vacuum wax oil and residual oil. The method uses a Y-type molecular sieve and a ZSM-5 molecular sieve as active centers; a riser reactor or a fluidized bed reactor is adopted; the feed reactor and the recycle reactor for the C4 olefin-250 ℃ product share a single regenerator. The method solves the problem of the output of part of diesel oil at will, but cannot solve the problem of the accumulation of alkane components and polycyclic aromatic hydrocarbon components.

CN 1667089A discloses a method for producing low-carbon olefin by using gasoline, kerosene, diesel oil, vacuum wax oil, residual oil and mixture as raw materials. The method comprises the steps of firstly carrying out hydrotreating on a raw material and a circulating material flow, and then feeding the material flows into a catalytic cracking reactor. Wherein the gas recycle is ethane, propane and C4. The liquid circulation feed is C5-C6, heavy gasoline aromatic raffinate oil, LCO, HCO and oil slurry. Although the method solves the problem of the output of most by-products, the method cannot solve the problem of the accumulation of alkane components and polycyclic aromatic hydrocarbon components.

CN101747928A discloses a method for producing low-carbon olefins and aromatics from vacuum wax oil and residual oil. The process combines catalytic cracking and steam cracking. The method comprises the steps of separating c 2-gasoline alkane from a catalytic cracking product, feeding the separated product into a steam cracking reactor, and feeding butylene, recycle oil and oil slurry back to the catalytic cracking reactor. Aromatic hydrocarbons are produced by an aromatic extraction process. The method solves the problem of accumulation of alkane components and polycyclic aromatic hydrocarbon components. However, the separation of olefins and paraffins from components above C4 is very energy intensive and is not reimburseable.

In the above method, since the reaction speed of the tetracarbon is significantly slower than that of the tetracarbon, the conversion rate of the tetracarbon is high and the conversion rate of the tetracarbon is extremely low in the mixed tetracarbon reaction process in the riser reactor. In the prior art, in the carbon four-component cycle reaction process, unreacted carbon tetralkyl hydrocarbon is retained in the carbon four-component, and alkane generated by raw oil is continuously accumulated in a cycle material flow. There is caused a problem that if the carbon four cycle ratio is not increased, the propylene yield is lowered due to the decrease in the olefin content in carbon four. If the carbon four cycle ratio is increased, the energy consumption is greatly increased.

Disclosure of Invention

One of the technical problems to be solved by the invention is to solve the problems in the process of preparing low-carbon olefin by hydrocarbon oil in the prior art, and provide a method for producing ethylene, propylene and aromatic hydrocarbon by heavy oil, which reduces the accumulation of alkane components and has high product yield.

The second technical problem to be solved by the invention is to provide a catalytic conversion device for producing ethylene, propylene and aromatic hydrocarbon from heavy oil.

The invention provides a method for producing ethylene, propylene and aromatic hydrocarbon, which comprises the following steps:

(1) the heavy oil raw material enters a first reactor, contacts and reacts with a first strand of regenerated catalyst from a regenerator, the mixture of oil gas and catalyst obtained by the reaction is subjected to gas-solid separation, and the separated catalyst to be regenerated is sent to the regenerator to be coked and regenerated and heated; the separated reaction oil gas is separated into dry gas, liquefied gas, gasoline, diesel oil and oil slurry through a first separation system, and further ethylene, propylene, aromatic hydrocarbon products and four carbon components are separated;

(2) introducing a part of the carbon four components into a second reactor independently or together with external carbon four components, carrying out contact reaction with a second strand of regenerated catalyst from a regenerator, and introducing an oil gas and catalyst mixture obtained by the reaction into a settler of the first reactor for gas-solid separation;

(3) the rest of the four carbon components enter an aromatization reactor to contact and react with an aromatization catalyst, and dry gas, liquefied gas and gasoline rich in aromatic hydrocarbon are separated from reaction products through a second separation system, so that ethylene, propylene and aromatic hydrocarbon products are further separated.

The catalytic conversion device for producing the ethylene, the propylene and the aromatic hydrocarbon is used for the catalytic cracking method for producing the ethylene, the propylene and the aromatic hydrocarbon, and comprises the following steps: the system comprises a first reactor, a second reactor, a gas-solid separation device, a regenerator, a first oil-gas separation system, an aromatization reactor and a second oil-gas separation system; the regenerator has a regenerant outlet communicated with the bottoms of the first reactor and the second reactor, the first reactor and the second reactor share a set of gas-solid separation equipment, a spent agent outlet of the gas-solid separation equipment is communicated with the regenerator, an oil gas outlet of the gas-solid separation equipment is communicated with the first separation system, a C4 outlet of the first separation system is respectively communicated with the second reactor and the aromatization reactor, and an aromatization reactor outlet is communicated with the second separation system.

The method for producing ethylene, propylene and aromatic hydrocarbon and the catalytic conversion device provided by the invention have the beneficial effects that:

the method takes the heavy oil as the raw material to produce the ethylene, the propylene and the aromatic hydrocarbon, and can produce the ethylene, the propylene and the aromatic hydrocarbon to the maximum extent. The method solves the problem of alkane accumulation in the carbon four-cycle, greatly increases ethylene, propylene and aromatic hydrocarbon, and also greatly reduces the energy consumption and the operation cost of the carbon four-cycle; the method reduces the coke yield of the catalytic cracking unit required to meet the heat balance; the method can also reduce the heat load of the aromatization device and reduce the energy consumption of the aromatization device; the method can provide more high-quality cracking raw materials of ethane, propane and n-butane for steam cracking by using the heavy oil, thereby greatly increasing the yield of ethylene and propylene.

Drawings

FIG. 1 is a schematic flow diagram of a process for producing ethylene, propylene and aromatic hydrocarbons according to the present invention.

FIG. 2 is a schematic flow chart of a process for producing ethylene and propylene from the heavy oil in comparative examples 1 and 2.

Wherein:

202-a first reactor; 206-a regenerator; 210-a second reactor; 222-a stripper; 224-a settler; 226-a fractionation column; 230-rear light hydrocarbon separation system; 233-gas separation device; 237-an aromatization reactor; the rest is a pipeline.

Detailed Description

The following specifically describes embodiments of the present invention:

a process for producing ethylene, propylene and aromatic hydrocarbons comprising:

In the method provided by the invention, the heavy oil raw material is one or a mixture of more of wax oil, atmospheric residue, vacuum residue and organic compound with carbon number more than 16.

In the method provided by the invention, the catalyst in the steps (1) and (2) is a catalytic cracking catalyst and contains an MFI structure molecular sieve, a Y-type molecular sieve, clay and a binder, wherein based on the total weight of the catalyst, the MFI structure molecular sieve content is 5-60 wt%, preferably 10-50 wt%, the Y-type molecular sieve content is 1-40 wt%, preferably 1-30 wt%, the clay content is 10-70 wt%, preferably 15-45 wt%, and the binder content is 5-40 wt%, preferably 5-35 wt%.

Preferably, the extraneous carbon four component is a carbon four component having an olefin content greater than 20%.

In the method provided by the invention, the first reactor is one or a combination of a riser reactor, a turbulent bed reactor and a fast bed reactor; the operating conditions of the first reactor were: the average temperature is 500-700 ℃, the reaction pressure is 0.15-0.5 MPa, and the reaction space velocity is 2-600 h^-1

In the method provided by the invention, the second reactor is one or a combination of a riser reactor, a turbulent bed reactor and a fast bed reactor; the operating conditions of the reactor were: the average temperature is 550-700 ℃, the reaction pressure is 0.15-0.5 MPa, and the reaction space velocity is 2-600 h^-1. The process of the present invention provides a process wherein the C.sub.four component separated in step (1) comprises C4 olefins and C4 alkanes, typically having an olefin content of greater than 20 wt%, preferably an olefin content of from 40 to 90 wt%.

In the method provided by the invention, the operation conditions of the aromatization reactor are as follows: the reaction temperature is 350-450 ℃, the reaction pressure is 0.20-2.0 MPa, and the reaction space velocity is 0.2-2 h^-1。

In the method provided by the invention, the aromatization catalyst contains a molecular sieve, a metal active component and a heat-resistant inorganic oxide carrier, wherein the metal active component is selected from one or more of rare earth elements, VIB, VIII, IIB and VIIB group elements, and the heat-resistant inorganic oxide is preferably silicon oxide and aluminum oxide.

In the method provided by the invention, the gas-solid separation in the steps (1) and (2) is carried out in a settler, a cyclone gas-solid separator is adopted to separate the catalyst and the reaction oil gas, the separated catalyst is subjected to steam stripping in a steam stripper, and the oil gas adsorbed on the catalyst is removed.

In the method provided by the invention, the aromatic hydrocarbon obtained in the step (3) is C6-C10 monocyclic aromatic hydrocarbon.

A catalytic converter for producing ethylene, propylene and aromatic hydrocarbons, for use in the above catalytic cracking process for producing ethylene, propylene and aromatic hydrocarbons, comprising: the system comprises a first reactor, a second reactor, a gas-solid separation device, a regenerator, a first oil-gas separation system, an aromatization reactor and a second oil-gas separation system; the regenerator has a regenerant outlet communicated with the bottoms of the first reactor and the second reactor, the first reactor and the second reactor share a set of gas-solid separation equipment, a spent agent outlet of the gas-solid separation equipment is communicated with the regenerator, an oil gas outlet of the gas-solid separation equipment is communicated with the first separation system, a C4 outlet of the first separation system is respectively communicated with the second reactor and the aromatization reactor, and an aromatization reactor outlet is communicated with the second separation system.

In the catalytic conversion device for producing ethylene, propylene and aromatic hydrocarbon, the first reactor and the second reactor are one or a combination of a riser reactor, a turbulent bed reactor and a fast bed reactor, and the aromatization reactor is a fixed bed reactor.

The regenerator is a regenerator of various forms in the art, which uses air or air mixed oxygen-rich gas to react with coke on the spent catalyst, burns off the coke on the spent catalyst to restore the activity of the spent catalyst (called regenerated catalyst), and raises the catalyst temperature to 600 ℃ to 760 ℃ in order to return to the reactor to bring heat and catalytic media to the reaction.

The invention provides a method and a device, wherein a first reactor and a second reactor share a set of a settler and a stripper. The first separation system and the second separation system can adopt one or more combinations of a fractionating tower, a rectifying tower, an absorption tower and a desorption tower.

The method is described below with reference to the accompanying drawings, but the invention is not limited thereto.

FIG. 1 is a schematic flow diagram of the method provided by the present invention, as shown in FIG. 1, a heavy oil feedstock is preheated and then enters a first reactor 202 through a line 201 to contact and react with a regenerated catalyst coming from a regenerator 206 through a regenerated catalyst inclined tube 209, the first reactor is a riser reactor, the generated oil gas and catalyst enter a settler 224, the oil gas and catalyst in the settler 224 are separated, the separated spent catalyst with carbon enters a stripping section 222 to be stripped, and then enters the regenerator 206 through a spent catalyst inclined tube 223, the air coming from the regenerator 206 through a line 301 burns coke on the spent catalyst to restore activity, and then enters the bottom of the first reactor 202 through the regenerated catalyst inclined tube 209 to be recycled; the separated oil and gas is passed via line 225 to fractionation column 226. Product diesel 227 is withdrawn from the middle of the fractionation column 226. Product slurry 228 is drawn off at the bottom. The products below the gasoline obtained from the top of the fractionating tower 226 enter a rear light hydrocarbon separation system 230 through a pipeline 229 to separate a product gasoline 304, a dry gas 231 and a liquefied gas 232, and the liquefied gas 232 enters a gas separation device 233 to separate propylene 234, propane 235 and a carbon four component 236.

A part of the carbon four components 236 enter the second reactor 210 through a pipeline 221 and contact with the hot regenerated catalytic catalyst from the regenerator 206 through the regenerant inclined tube 200, the generated oil gas and the generated catalyst enter the settler 224, the oil gas and the catalyst are separated in the settler 224, and the separated carbon-containing catalyst enters the regenerator 206 through a stripping section 222 and is burnt through a pipeline 223. The air from the regenerator 206 via line 301 burns the coke on the catalyst to restore activity, and then enters the bottom of the reactor 210 via line 200 to participate in the reaction, and the separated oil gas and gas enter the fractionating tower 226 via line 204.

The remaining carbon four components are passed via line 240 to carbon four aromatization unit 237. The products are separated to obtain the gasoline 239 rich in aromatic hydrocarbon, the dry gas 305 and the liquefied gas 238.

The dry gas 231 and the dry gas 305 separate ethylene and ethane, as well as other gases.

The effect of the process for producing ethylene, propylene and aromatic hydrocarbons from heavy oil provided by the present invention is illustrated below by examples and comparative examples, but the present invention is not limited thereby.

In the comparative example and the example, the heavy oil raw material A used is hydrogenated residual oil which is taken from the Shijiazhuan oil refinery of the China petrochemical Co Ltd; the heavy oil raw material B is straight-run wax oil and is obtained from Yanshan division of the China petrochemical industry, Inc. The properties of the heavy oil feedstock A, B are shown in table 1. The catalyst used is DMMC-1 catalyst produced by catalyst division of China petrochemical company Limited. The properties are shown in Table 2.

Comparative examples 1 to 2

Comparative examples 1-2 a process flow schematic of a process for producing ethylene and propylene by catalytic cracking of heavy oil as shown in fig. 2 is adopted, as shown in fig. 2, raw heavy oil is preheated and then enters a catalytic cracking riser reactor 102 through a line 101 to contact with a regenerated catalyst coming from a regenerator 106 through a line 109, the generated oil gas and catalyst enter a settler 103, the oil gas and catalyst are separated in the settler 103, and the separated catalyst with carbon is stripped by a stripper 402 and then enters the regenerator 106 through a line 105 to be burned. The air from the regenerator 106 via line 108 burns the coke on the catalyst to restore activity, and then enters the bottom of the reactor 102 via line 109 to participate in the reaction, and the separated oil gas enters the fractionating tower 111 via line 104. The product diesel 112 is withdrawn from the middle of the fractionation column 111. The product slurry 113 is drawn off at the bottom. The products below the gasoline obtained from the top of the fractionating tower 111 enter a post-absorption stabilizing system 115 through a pipeline 114, the products gasoline 116 separated by the stabilizing system, dry gas 401 and liquefied gas 117 enter a gas separation device 118, and propylene 119, propane 120 and carbon four components 121 are separated from the liquefied gas 117.

The carbon four components 121 enter the catalytic cracking riser reactor 110 to contact with the regenerated catalyst heated by the regenerator 106 through the pipeline 100, the generated oil gas and the catalyst enter the settler 124, the oil gas and the catalyst are separated in the settler 124, and the separated catalyst with carbon enters the regenerator 206 through the stripping section 402 and the pipeline 123 to be burnt. Air via line 108 in regenerator 106 burns coke from the catalyst to restore activity and then enters the bottom of reactor 110 via line 100 to recycle and participate in the reaction. The dry gas 401 enters the separation system 124 to separate the ethylene 125, other components 126 and ethane 123.

The reaction conditions of comparative examples 1-2 are shown in Table 3, and the product yields are shown in Table 4.

Examples 1 to 2

The embodiment 1-2 adopts a reaction flow shown in the attached figure 1, specifically, (1) heavy oil raw materials enter a first reactor to contact and react with a first strand of regenerated catalyst from a regenerator, a mixture of oil gas and catalyst obtained by the reaction is subjected to gas-solid separation, and the separated spent catalyst is sent to the regenerator to be burnt and regenerated and heated; the separated reaction oil gas is separated into dry gas, liquefied gas, gasoline, diesel oil and oil slurry through a first separation system, and further ethylene, propylene, aromatic hydrocarbon products and four carbon components are separated;

(2) introducing one part of the four carbon components into a second reactor, carrying out contact reaction with a second strand of regenerated catalyst from a regenerator, and allowing a mixture of oil gas and catalyst obtained by the reaction to enter a settler of the first reactor for gas-solid separation;

(3) the rest part of the separated carbon four components enters an aromatization reactor to contact and react with an aromatization catalyst, and dry gas, liquefied gas and gasoline rich in aromatic hydrocarbon are separated from reaction products through a second separation system, so that ethylene, propylene and aromatic hydrocarbon products are further separated.

The reaction conditions of examples 1-2 are shown in Table 3, and the product yields are shown in Table 4.

As can be seen from table 4, the carbon four feed/feed for the examples of feed a and feed B are reduced by 0.05 and 0.10, respectively, ethylene by 0.33 and 0.48 percentage points, propylene by 0.60 and 0.97 percentage points, and BTX by 1.18 and 2.95 percentage points, respectively, compared to the comparative example.

TABLE 1

Raw oil	Starting materials A	Raw material B
			Density (20 ℃ C.)/(kg/m)³)	934	862
C/wt％	87.15	86.3
			H/wt％	12.15	13.63
S/wt％	0.42	0.08
			N/wt％	0.22	0.05
Carbon residue value/wt%	5.58	0.10
			Distillation range/. degree.C
5％	365	343
			10％	403	368
30％	479	410
			50％	545	437
70％	617	465
			Metal mass fraction/(mug/g)
Ni	9	0.1
			V	8	0.1

TABLE 2

TABLE 3

Item	Comparative example 1	Example 1	Comparative example 2	Example 2
					Raw oil	Starting materials A	Starting materials A	Raw material B	Raw material B
Operating parameters of raw material reaction
					Catalyst and process for preparing same	DMCC-1	DMCC-1	DMCC-1	DMCC-1
First reactor operating conditions
					Reaction pressure/MPa	0.2	0.2	0.28	0.28
Reaction temperature/. degree.C	555	555	620	620
					Regenerator temperature/. degree.C	690	690	710	710
Ratio of agent to oil	10	10	15	15
					Reaction space velocity/h^-1	14	14	5	5
Atomized steam/%)	25	25	15	15
					Second reactor operating conditions
Carbon four feed/stock oil	0.25	0.20	0.40	0.3
					Reaction pressure/MPa	0.2	0.2	0.28	0.28
Reaction temperature/. degree.C	600	600	640	640
					Regenerator temperature/. degree.C	690	690	710	710
Ratio of agent to oil	8	8	12	12
					Reaction space velocity/h^-1	50	50	8	8
Atomized steam/%)	10	10	25	25

TABLE 4

Example numbering	Comparative example 1	Example 1	Comparative example 2	Example 2
					Product yield, wt%
H2-C2	13.69	13.98	16.11	17.01
					C3-C4	22.93	21.85	39.25	37.25
C5+ gasoline	29.44	30.16	26.89	27.85
					Diesel oil	16.30	16.35	8.68	8.74
Heavy oil	5.70	5.71	2.18	2.20
					Coke	11.94	11.95	6.89	6.95
Ethylene	8.00	8.33	10.67	11.15
					Propylene (PA)	19.05	19.65	30.26	31.23
BTX	9.35	10.53	7.5	10.45

Claims

1. A process for producing ethylene, propylene and aromatic hydrocarbons comprising:

2. The process for producing ethylene, propylene and aromatic hydrocarbons according to claim 1, wherein the heavy oil feedstock is selected from one or more of wax oil, atmospheric residue, vacuum residue and organic compounds having a carbon number greater than 16.

3. The method for producing ethylene, propylene and aromatic hydrocarbons according to claim 1, wherein the catalyst in the step (1) and (2) is a catalytic cracking catalyst comprising an MFI structure molecular sieve, a Y-type molecular sieve, clay and a binder, and based on the total weight of the catalyst, the MFI structure molecular sieve is 5 to 60 wt%, the Y-type molecular sieve is 1 to 40 wt%, the clay is 10 to 70 wt% and the binder is 5 to 40 wt%.

4. The method for producing ethylene, propylene and aromatic hydrocarbons according to claim 3, wherein the MFI structure molecular sieve is 10 to 50 wt%, the Y-type molecular sieve is 1 to 30 wt%, the clay is 15 to 45 wt%, and the binder is 5 to 30 wt%, based on the total weight of the catalyst.

5. The process for producing ethylene, propylene and aromatic hydrocarbons according to claim 1, wherein said foreign carbon four component is a carbon four component having an olefin content of more than 20%.

6. The process for producing ethylene, propylene and aromatic hydrocarbons according to claim 1, wherein the first reactor is one or more of a riser reactor, a turbulent bed reactor and a fast bed reactorSeveral combined reactors; the operating conditions of the first reactor were: the average temperature is 500-700 ℃, the reaction pressure is 0.15-0.5 MPa, and the reaction space velocity is 2-600 h^-1。

7. The process for producing ethylene, propylene and aromatic hydrocarbons according to claim 1, wherein the second reactor is one or a combination of a riser reactor, a turbulent bed reactor and a fast bed reactor; the operating conditions of the reactor were: the average temperature is 550-700 ℃, the reaction pressure is 0.15-0.5 MPa, and the reaction space velocity is 2-600 h^-1。

8. The process for producing ethylene, propylene and aromatic hydrocarbons according to claim 1, wherein the C-tetrad separated in the step (1) contains C4 olefins and C4 alkanes, and generally has an olefin content of more than 20 wt%.

9. The process for producing ethylene, propylene and aromatic hydrocarbons according to claim 8, wherein the olefin content of the carbon four components separated in the step (1) is 40 to 90 wt%.

10. The process for producing ethylene, propylene and aromatic hydrocarbons according to claim 1, wherein the operating conditions of the aromatization reactor in step (3) are: the reaction temperature is 350-450 ℃, the reaction pressure is 0.20-2.0 MPa, and the reaction space velocity is 0.2-2 h^-1。

11. The process for producing ethylene, propylene and aromatic hydrocarbons according to claim 1, wherein the aromatization catalyst comprises a molecular sieve, a metal active component and a refractory inorganic oxide carrier, the metal active component is selected from one or more of rare earth elements, VIB, VIII, IIB and VIIB elements, and the refractory inorganic oxide is preferably silicon oxide and aluminum oxide.

12. The process for producing ethylene, propylene and aromatic hydrocarbons according to claim 1, wherein the gas-solid separation in the step (1) (2) is carried out in a settler, the catalyst and the reaction oil gas are separated by a cyclone gas-solid separator, and the separated catalyst is stripped in a stripper.

13. A catalytic converter for producing ethylene, propylene and aromatic hydrocarbons for use in the catalytic cracking process for producing ethylene, propylene and aromatic hydrocarbons of claims 1-12, comprising: the system comprises a first reactor, a second reactor, a gas-solid separation device, a regenerator, a first oil-gas separation system, an aromatization reactor and a second oil-gas separation system; the regenerator has a regenerant outlet communicated with the bottoms of the first reactor and the second reactor, the first reactor and the second reactor share a set of gas-solid separation equipment, a spent agent outlet of the gas-solid separation equipment is communicated with the regenerator, an oil gas outlet of the gas-solid separation equipment is communicated with the first separation system, a C4 outlet of the first separation system is respectively communicated with the second reactor and the aromatization reactor, and an aromatization reactor outlet is communicated with the second separation system.

14. The catalytic converter apparatus for producing ethylene, propylene and aromatic hydrocarbons according to claim 13, wherein the first reactor and the second reactor are one or a combination of a riser reactor, a turbulent bed reactor and a fast bed reactor, and the aromatization reactor is a fixed bed reactor.