CN108300508A - Heavy oil millisecond is classified gas phase catalysis and cracks producing light olefins coupling device - Google Patents

Abstract

The invention provides a coupling device for producing low-carbon olefins by millisecond fractional gas-phase catalytic cracking of heavy oil. The downstream modified reaction tube is connected with the modified regeneration reactor through a gas-solid separator, a return controller and a flow regulator to form a circular reaction system; The upper part of the reaction tube is equipped with high-efficiency atomizing nozzles, and the lower part is equipped with a gas-solid rapid separator; the bottom of the modified regeneration reactor is equipped with a regenerant inlet, and the top is equipped with a gas-solid separator; the millisecond cracking reactor passes through the gas-solid separator, return The material controller and flow regulator are connected with the pyrolysis regeneration reactor to form another circular reaction system; the outlet of the pyrolysis oil gas and the outlet of the return controller are directly connected to the inlet of the millisecond pyrolysis reactor, and the outlet of the millisecond pyrolysis reactor is connected to the gas-solid rapid separation There is an air inlet at the bottom of the pyrolysis regenerative reactor, and a gas-solid separator at the top is connected to the return controller. The return controller is connected to the millisecond cracking reactor, and the gas outlet of the gas-solid separator is connected to the flue gas The outlet is connected.

Description

Heavy oil millisecond fractional gas-phase catalytic cracking to light olefins coupling device

1. Technical field

The invention provides a coupling device for preparing low-carbon olefins by millisecond fractional gas-phase catalytic cracking of heavy oil, belonging to the field of petroleum processing.

2. Background technology

Low-carbon olefins such as ethylene, propylene, butene and butadiene are very important basic organic chemical raw materials, especially the production capacity of ethylene is often regarded as a symbol of the petrochemical development level of a country and region. Due to the explosive development of energy storage battery technology and the impending implementation period of the National VI emission standard, which is known as the world's most stringent motor vehicle exhaust, electric vehicles have emerged with the advantages of nearly zero pollution during driving, energy saving, low cost of use, and easy intelligence. Fuel vehicles have become an irreversible development trend, followed by a sharp decline in transportation oil consumption, and the transformation and upgrading of petroleum processing enterprises from "fuel-based" to "chemical-based" is imminent.

At present, about 95% of ethylene and 66% of propylene in the world are produced by using light raw materials such as natural gas, naphtha or light diesel oil through tube furnace steam pyrolysis process. However, in the 21st century, with the depletion of conventional crude oil resources, the world's crude oil supply has shown a trend of heavy and poor quality, resulting in a relative shortage of light cracking raw materials, and the worldwide market demand for low-carbon olefins is growing rapidly. In order to alleviate this contradiction, broaden the raw materials for the production of low-carbon olefins, and at the same time, in order to make better use of heavy feedstock oil, develop a "chemical-type" technical route that uses heavy oil as raw material and directly produces low-carbon olefins through catalytic cracking technology. It is the focus and focus of domestic and foreign petroleum refining research and attention, but there are very few mature technologies that can be industrialized.

In recent years, many heavy oil catalytic cracking technologies to produce low-carbon olefins have been developed, such as the DCC/CPP process developed by Sinopec Academy of Petroleum Science[4-5], the PetroFCC process developed by UOP, and the HS-FCC process developed by Japan Petroleum Energy Center. , THR process, TCSC process of German Institute of Organic Chemistry, INDMAX (UCC) process developed by Indian Oil Corporation, Maxofin process jointly developed by Exxon mobil and Kellog, and two-stage riser catalytic cracking (TMP) process proposed by China Petroleum Science, etc. , has received extensive attention and demonstration applications in the industry. Compared with steam cracking, it has the advantages of widening the range of olefin raw materials, low reaction temperature, easy adjustment of product distribution and low energy consumption. However, on the one hand, these catalytic cracking processes should adopt high temperature, short residence time, large ratio of agent to oil, and large ratio of water to oil; important factor in rate and distribution. However, the active components of heavy oil catalytic cracking catalysts are mainly ZSM-5 and Y-type molecular sieves, whose pore structure is small, and the diffusion of larger heavy oil molecules is limited during the mass transfer process, so it is difficult to enter the interior of molecular sieves for shape-selective cracking. Coupled with the strong hydrogen transfer performance of acidic molecular sieves, the yield and selectivity of olefins are limited; in addition, heavy oil macromolecules accumulated on the surface of molecular sieves are prone to excessive cracking under the action of acid centers, resulting in poor product distribution or coking condensation. thereby clogging the catalyst pores. At present, the existing industrial type-selective catalysts use atmospheric residue, vacuum residue, deasphalted oil and other inferior raw materials to catalytically crack low-carbon olefins, which often leads to catalyst poisoning, poor atomization effect, large coke formation and conversion The rate and selectivity are greatly reduced and many other problems.

In addition, in the existing thermal processing process of heavy oil, the reaction of hydrocarbons mainly occurs in liquid phase. In the gas phase, hydrocarbon molecules can be quickly dispersed after splitting into free radicals, while the free radicals in the liquid phase are surrounded by surrounding molecules like "cages", and the polycondensation reaction will intensify. To disperse the formed free radicals, an additional barrier to diffusion from the "cage" must be overcome, which is the so-called "cage effect". This "cage effect" changes the activation energy and reaction velocity of liquid-phase reactions relative to gas-phase reactions. Wu et al. compared the liquid-phase reaction and gas-phase reaction process of n-hexadecane, and found that the liquid-phase reaction process will reduce the selectivity of gas products and generate more polymers, while the gas-phase reaction process can increase the content of olefins in the gas products. .

How to develop processes and equipment to eliminate carbon residues and heavy metal pollution in heavy oil, and maximize the acquisition of low-carbon olefins has become a major issue to be solved in the process of transformation and upgrading of petrochemical processing in my country.

3. Contents of the invention

The purpose of the present invention is to overcome the shortcomings of the existing heavy oil processing devices and provide a coupling device for producing low-carbon olefins by millisecond fractional gas-phase catalytic cracking of heavy oil, which utilizes millisecond pyrolysis of heavy oil downpipes to maximize the production of oil and gas, and high-temperature oil and vapor do not undergo condensation and separation. , Direct high-temperature millisecond type-selective catalytic cracking to produce low-carbon olefins, so as to make full use of the heat of pyrolysis oil and gas, greatly improve the yield and selectivity of low-carbon olefins, overcome the "cage effect" of liquid phase reaction, and reduce the heat mass The impact of transmission on catalytic cracking greatly reduces the amount of coke and energy consumption in the cracking process, thereby realizing high-efficiency and high-yield chemical processing of heavy oil.

Technical scheme of the present invention:

Millisecond fractional gas-phase catalytic cracking of heavy oil to produce low-carbon olefins coupling device, which consists of gas-solid separator, return controller, high-efficiency atomization nozzle, downstream modification reaction tube, gas-solid fast separator, pyrolysis oil and gas outlet, flow regulator, Composed of millisecond pyrolysis reactor, regeneration agent inlet, modified regeneration reactor, heat exchanger, regeneration gas outlet, cracking regeneration reactor, air inlet, and flue gas outlet. The downward modified reaction tube is connected to the modified regeneration reactor through the gas-solid separator, the return controller and the flow regulator to form a circular reaction system; the upper part of the downward modified reaction tube is equipped with symmetrical high-efficiency atomizing nozzles, and the lower part is equipped with The gas-solid rapid separator, the gas outlet of the gas-solid rapid separator is the outlet of pyrolysis oil and gas, the solid outlet of the gas-solid rapid separator is connected to the lower part of the modified regeneration reactor through a flow regulator; the bottom of the modified regeneration reactor is provided with a regeneration agent inlet , the top is provided with a gas-solid separator; the solid outlet of the gas-solid separator is connected downward to the return controller, and the outlet of the return controller is connected to the top of the downward modified reaction tube, and the gas outlet of the gas-solid separator passes through the heat exchanger and the regeneration The gas outlet is connected; the millisecond pyrolysis reactor is connected with the cracking regeneration reactor through the gas-solid separator, the return controller and the flow regulator to form another cycle reaction system; the pyrolysis oil gas outlet and the return controller outlet are directly connected to the millisecond The inlet of the pyrolysis reactor and the outlet of the millisecond cracking reactor are connected to the gas-solid rapid separator; the solid outlet of the gas-solid rapid separator is connected to the lower part of the pyrolysis regeneration reactor through a flow regulator, and the gas outlet of the gas-solid rapid separator is the pyrolysis oil and gas outlet; pyrolysis regeneration There is an air inlet at the bottom of the reactor, and a gas-solid separator at the top; the solid outlet of the gas-solid separator is connected downwards to the return controller, and the outlet of the return controller is connected to the inlet of the millisecond pyrolysis reactor, and the gas outlet of the gas-solid separator It is connected to the flue gas outlet through a heat exchanger.

The reaction temperature of the downstream modified reaction tube is 480°C-850°C, and the solid heat carrier is semi-coke microspheres, alumina microspheres, calcium aluminate porous microspheres, magnesium aluminum spinel porous microspheres, aluminum silicate porous microspheres , a mixture of one or more of calcium silicate porous microspheres, magnesium silicate porous microspheres, porous microsphere carriers loaded with alkali metals or/and alkaline earth metals.

The reaction temperature of the modified regeneration reactor is 650°C-1250°C. The modified regeneration reactor is a combination of one or more of the riser regenerator, turbulent fluidized bed regenerator, and bubbling fluidized bed regenerator. The agent is a mixture of oxidant and water vapor or an oxidant, and the oxidant is one of oxygen, air and oxygen-enriched air; the regeneration gas is synthesis gas or flue gas.

The reaction temperature of the cracking reactor is 530°C-750°C. The cracking catalyst is a mixture of one or more of ZSM-5 molecular sieve catalysts, FCC molecular sieve catalysts, shape-selective molecular sieve catalysts, and basic solid porous catalysts. The millisecond cracking reactor is It is one of the down tube reactor, horizontal inertial cyclone reactor and cross staggered short contact reactor.

The reaction temperature of the cracking regeneration reactor is 630°C-900°C, and the cracking regeneration reactor is one or a combination of riser regenerator, turbulent fluidized bed regenerator, and bubbling fluidized bed regenerator.

The gas-solid separator is a combination of one or more of inertial separators, horizontal cyclone separators, and vertical cyclones.

The return controller and the flow controller are non-mechanical control valves or mechanical control valves, and the non-mechanical control valve is one of the L-type feeder, U-type feeder, J-type feeder and N-type feeder Or multiple combinations, mechanical control valves are hydraulic sliding plug valves and electric sliding plug valves.

The present invention will describe the characteristics of the present invention in detail through examples.

4. Description of drawings

Accompanying drawing 1 is the structural representation of the present invention.

The drawings of the accompanying drawings are set as follows:

1. Gas-solid separator, 2. Return material controller, 3. High-efficiency atomizing nozzle, 4. Downstream modified reaction tube, 5. Gas-solid rapid separator, 6. Pyrolysis oil and gas outlet, 7. Flow regulator, 8. Millisecond pyrolysis reactor, 9. Regenerant inlet, 10. Modified regeneration reactor, 11. Heat exchanger, 12. Regeneration gas outlet, 13. Cracking regeneration reactor, 14. Air inlet, 15. Flue gas outlet .

The features of the present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

5. Specific implementation

Example, a coupling device for producing low-carbon olefins by millisecond fractional gas-phase catalytic cracking of heavy oil, consisting of a gas-solid separator (1), a return controller (2), a high-efficiency atomizing nozzle (3), a downstream modification reaction tube (4), Gas-solid rapid separator (5), pyrolysis oil and gas outlet (6), flow regulator (7), millisecond cracking reactor (8), regenerant inlet (9), modified regeneration reactor (10), heat exchange device (11), regeneration gas outlet (12), cracking regeneration reactor (13), air inlet (14), flue gas outlet (15). The downstream modified reaction pipe (4) is connected to the modified regeneration reactor (10) through the gas-solid separator (1), the return controller (2) and the flow regulator (7) to form a circular reaction system; the downstream modified The upper part of the reaction tube (4) is equipped with a symmetrical high-efficiency atomizing nozzle (3), and the lower part is equipped with a gas-solid quick separator (5). The gas outlet of the gas-solid quick separator (5) is a pyrolysis oil gas outlet (6), and the gas The solid outlet of the solid quick separator (5) communicates with the lower part of the modified regeneration reactor (10) through a flow regulator (7); The solid separator (1); the solid outlet of the gas-solid separator (1) leads downward to the return controller (2), and the outlet of the return controller (2) is connected to the top of the downward modification reaction tube (4), and the gas-solid The gas outlet of the separator (1) is connected to the regeneration gas outlet (12) through a heat exchanger (11); the millisecond cracking reactor (8) is passed through a gas-solid separator (1), a return controller (2) and a flow regulator (7) communicate with the pyrolysis regeneration reactor (13) to form another circulating reaction system; the pyrolysis oil gas outlet (6) and the return controller outlet (2) are directly connected to the millisecond cracking reactor (8) inlet together, and the millisecond cracking The outlet of the reactor (8) is connected to the gas-solid quick separator (5); the solid outlet of the gas-solid quick separator (5) is communicated with the lower part of the pyrolysis regeneration reactor (13) through a flow regulator (7), and the gas-solid quick separator ( 1) The gas outlet is the cracked oil and gas outlet; the bottom of the cracking regeneration reactor (13) is provided with an air inlet (14), and the top is provided with a gas-solid separator (1); the solid outlet of the gas-solid separator (1) leads downward to the return The feed controller (2), the feed return controller (2) outlet is connected to the millisecond cracking reactor (8) inlet, the gas outlet of the gas-solid separator (1) is connected to the flue gas outlet (15) through the heat exchanger (11) .

The reaction temperature of the downward modified reaction tube (4) is 480°C-850°C, and the solid heat carrier is semi-coke microspheres, alumina microspheres, calcium aluminate porous microspheres, magnesium aluminum spinel porous microspheres, aluminum silicate A mixture of one or more of porous microspheres, calcium silicate porous microspheres, magnesium silicate porous microspheres, porous microsphere carriers loaded with alkali metals or/and alkaline earth metals.

The reaction temperature of the modified regeneration reactor (10) is 650°C-1250°C, and the modified regeneration reactor (10) is one of a riser regenerator, a turbulent fluidized bed regenerator, and a bubbling fluidized bed regenerator or A variety of combinations, the regeneration agent is a mixture of oxidant and water vapor or oxidant, the oxidant is one of oxygen, air and oxygen-enriched air; the regeneration gas is syngas or flue gas.

The reaction temperature of the millisecond cracking reactor (8) is 530°C-750°C, and the cracking catalyst is a mixture of one or more of ZSM-5 molecular sieve catalysts, FCC molecular sieve catalysts, shape-selective molecular sieve catalysts, and basic solid porous catalysts, milliseconds The cracking reactor (8) is one of a downcomer reactor, a horizontal inertial cyclone reactor and a cross-staggered short-contact reactor.

The reaction temperature of the cracking regeneration reactor (13) is 630°C-900°C, and the cracking regeneration reactor (13) is one or more of a riser regenerator, a turbulent fluidized bed regenerator, and a bubbling fluidized bed regenerator The combination.

The gas-solid separator (1) is a combination of one or more of inertial separators, horizontal cyclone separators and vertical cyclones.

The return controller (2) and the flow controller (7) are non-mechanical control valves or mechanical control valves, and the non-mechanical control valves are L-type return devices, U-type return devices, J-type return devices and N-type return devices. One or more combinations of feeders, mechanical control valves are hydraulic sliding plug valves and electric sliding plug valves.

During specific operation, the high-efficiency atomizing nozzle (3) sprays the heavy oil preheated to 150°C-350°C from the feed port of the down-going modification reaction pipe (4) into the upper part of the down-going modification reaction pipe (4), and the oil mist and The 650°C-1200°C high-temperature solid heat carrier flowing from the return controller (2) mixes, heats, vaporizes and pyrolyzes in milliseconds, and the pyrolysis reaction temperature is 480°C-850°C; Flow downstream to the gas-solid quick separator at the bottom of the modification reaction tube (4) for gas-solid separation; the coked solid heat carrier enters the lower part of the modification regeneration reactor (10) through the flow controller (7) and regenerant The regeneration agent flowing into the inlet (9) undergoes a regeneration reaction, and the regeneration reaction temperature is 680°C-1250°C, and the regeneration gas and high-temperature solid heat carrier are gas-solid separated in the gas-solid separator (1) at the top of the modified regeneration reactor (10). Solid separation, the high-temperature solid heat carrier flows into the top of the modified downward reaction tube (4) through the return controller (2) according to the carrier oil ratio of 1-14 to participate in circulation and crack heavy oil, and the regeneration gas passes through the heat exchanger (11) for heat exchange Afterwards, it is output from the regeneration gas outlet (12); the high-temperature oil gas directly enters the millisecond cracking reactor (8) in the gas phase without condensation and mixes with the regeneration cracking catalyst at 600°C-850°C, and a gas-phase catalytic cracking reaction occurs, and the cracking reaction temperature is 530°C- 750 DEG C, then the cracked gas and the uncooked cracking catalyst carry out millisecond gas-solid separation through the gas-solid separator (1); the uncooked cracking catalyst enters the lower part of the cracking regeneration reactor (13) through the flow controller (7) and from the air inlet ( 14) The incoming air undergoes a regeneration reaction, the regeneration reaction temperature is 630°C-900°C, the flue gas and the high-temperature cracking catalyst are separated from the gas-solid in the gas-solid separator (1) at the top of the cracking regeneration reactor (13), and the high-temperature cracking The catalyst flows into the millisecond cracking reactor (8) through the feed-return controller (2) according to the agent-oil ratio of 1-8 to participate in the cycle reaction, and the flue gas is output from the flue gas outlet (15) after heat exchange through the heat exchanger (11); The cracked oil and gas enter the subsequent separation device to separate light olefins and aromatics.

The coupling device for producing low-carbon olefins by millisecond fractional gas-phase catalytic cracking of heavy oil provided by the present invention utilizes rapid alkaline catalytic pyrolysis of inferior heavy oil to maximize the production of oil and gas. Carbon olefins, so as to make full use of the heat of pyrolysis oil and gas, overcome the "cage effect" of liquid phase reaction, reduce the impact of heat and mass transfer on catalytic cracking, and greatly reduce the amount of coke and energy consumption in the cracking process; reaction temperature And the time is easy to control, and at the same time, the characteristics of alkaline catalytic pyrolysis rich in olefins can be used for type-selective catalysis, which greatly improves the yield and selectivity of low-carbon olefins. The low-quality heavy oil triene "ethylene, propylene and The total yield of "butene" is as high as 50%, including 28% propylene and 15% ethylene, which is much higher than the 35% total yield of trienes from pyrolysis wax oil catalytic cracking; avoiding the traditional pyrolysis modification-wax oil catalytic cracking combination The wax oil in the process is reheated and atomized, but the "cage effect" of the liquid phase reaction still exists, which leads to the intensification of the polycondensation reaction, thereby reducing the yield and selectivity of low-carbon olefins. In addition, the process is short and the steel consumption of the equipment is low. , The fixed investment is greatly reduced; the normal pressure operation is simple, the start and stop are convenient, the continuity is good, and the adaptability to oil types is strong.

Claims (7)

1. Heavy oil millisecond fractional gas-phase catalytic cracking to low-carbon olefins coupling device, characterized in that the downstream modified reaction tube is connected to the modified regeneration reactor through a gas-solid separator, a return controller and a flow regulator to form a cyclic reaction system; The upper part of the downward modified reaction tube is equipped with a symmetrical high-efficiency atomization nozzle, and the lower part is equipped with a gas-solid rapid separator. The bottom of the modified regeneration reactor is connected to the lower part of the regeneration reactor; the bottom of the modified regeneration reactor is provided with a regenerant inlet, and the top is provided with a gas-solid separator; the solid outlet of the gas-solid separator is connected downward to the return controller, and the outlet of the return controller is connected to the downlink At the top of the modified reaction tube, the gas outlet of the gas-solid separator is connected to the regeneration gas outlet through a heat exchanger; the millisecond cracking reactor is connected to the cracking regeneration reactor through a gas-solid separator, a return controller and a flow regulator to form another cycle Reaction system; the pyrolysis oil and gas outlet and the outlet of the return controller are directly connected to the inlet of the millisecond pyrolysis reactor, and the outlet of the millisecond pyrolysis reactor is connected to the gas-solid rapid separator; the solid outlet of the gas-solid rapid separator reacts with cracking regeneration through a flow regulator The lower part of the gas-solid separator is connected, and the gas outlet of the gas-solid rapid separator is the cracked oil gas outlet; the bottom of the cracking regenerative reactor is equipped with an air inlet, and the top is equipped with a gas-solid separator; the solid outlet of the gas-solid separator is connected downward to the return controller, and the return The outlet of the material controller is connected to the inlet of the millisecond cracking reactor, and the gas outlet of the gas-solid separator is connected with the flue gas outlet through a heat exchanger. 2. According to claim 1, the coupling device for preparing low-carbon olefins by millisecond fractional gas-phase catalytic cracking of heavy oil is characterized in that the reaction temperature of the downstream modified reaction tube is 480°C-850°C, and the solid heat carrier is semi-coke microspheres, oxidized Aluminum microspheres, calcium aluminate porous microspheres, magnesium aluminum spinel porous microspheres, aluminum silicate porous microspheres, calcium silicate porous microspheres, magnesium silicate porous microspheres, alkali metal or/and alkaline earth metal loaded A mixture of one or more of porous microsphere carriers. 3. The combined riser gasification reactor according to claim 2, characterized in that the reaction temperature of the modified regeneration reactor is 650°C-1250°C, and the modified regeneration reactor is a riser regenerator, turbulent fluidized Bed regenerator, bubbling fluidized bed regenerator or a combination of one or more, the regenerant is a mixture of oxidant and water vapor or oxidant, the oxidant is one of oxygen, air and oxygen-enriched air; the regeneration gas is Syngas or flue gas. 4. According to claim 1, the coupling device for preparing low-carbon olefins by millisecond fractional gas-phase catalytic cracking of heavy oil is characterized in that the reaction temperature of the cracking reactor is 530°C-750°C, and the cracking catalyst is a ZSM-5 molecular sieve catalyst or an FCC molecular sieve catalyst , a type-selective molecular sieve catalyst, a mixture of one or more of the basic solid porous catalyst, and the millisecond cracking reactor is one of a downcomer reactor, a horizontal inertial cyclone reactor and a cross-staggered short-contact reactor. 5. According to claim 1, the coupling device for producing low-carbon olefins by millisecond fractional gas-phase catalytic cracking of heavy oil is characterized in that the reaction temperature of the cracking regeneration reactor is 630°C-900°C, and the cracking regeneration reactor is a riser regenerator, turbulent flow A combination of one or more of fluidized bed regenerators and bubbling fluidized bed regenerators. 6. According to the coupling device for producing low-carbon olefins by millisecond fractional gas-phase catalytic cracking of heavy oil according to claim 1, it is characterized in that the gas-solid fast separator and the synthesis gas separator are vertical cyclone separators, horizontal cyclone separators, inertial One or more combinations of separators. 7. According to the coupling device for producing low-carbon olefins by millisecond fractional gas-phase catalytic cracking of heavy oil according to claim 1, it is characterized in that the flow regulator is a non-mechanical control valve or a mechanical control valve, and the non-mechanical control valve is an L-shaped feeder, One or more combinations of U-type feeder, J-type feeder and N-type feeder, and the mechanical control valve is a hydraulic sliding plug valve and an electric sliding plug valve.