Conical cracking reactor, hydrocarbon cracking method and reaction system

Abstract

The present invention provides a conical cracking reactor, a hydrocarbon cracking method and a reaction system, wherein the conical cracking reactor comprises a conical reactor body and a quench heat exchanger connected to the lower end of the conical reactor body, the top of the conical reactor body is provided with at least one cracking raw material inlet, and the side wall of the conical reactor body is provided with at least one high-temperature flue gas inlet. The conical cracking reactor of the present invention greatly reduces the reaction residence time and prevents the problem of easy coking under high-pressure conditions. In addition, the present invention directly mixes the high-temperature flue gas generated in the combustion chamber with the raw material for heat exchange and generates a cracking reaction, which can increase the cracking reaction temperature and thus improve the cracking reaction depth, while making maximum use of the heat energy of fuel combustion.

Description

Technical Field

[0001] The invention relates to the technical field of hydrocarbon cracking, and in particular to a conical cracking reactor, a hydrocarbon cracking method and a reaction system. Background Art

[0002] In the field of hydrocarbon cracking, the existing industrial cracking furnaces mainly include regenerative cracking furnaces, sand cracking furnaces, molten salt cracking furnaces and tubular cracking furnaces. Among them, tubular cracking furnaces are widely used worldwide because of their ability to produce continuously, high quality cracking gas and mature technology. The tubular cracking furnace is mainly composed of two parts: the convection section and the radiation section. After the cracking raw materials are preheated, the dilution steam is added to heat up the convection section, and then enter the radiation section for cracking reaction. The generated cracking gas is quenched after leaving the furnace and sent to the downstream device. After the fuel is burned, it passes through the radiation section and the convection section for heat exchange, and finally the flue gas is discharged into the atmosphere. However, as the cracking device continues to develop towards large-scale, the disadvantages of the tubular cracking furnace are becoming increasingly apparent. At present, the main disadvantages are as follows:

[0003] (1) Due to the thermal tolerance limit of the heat-resistant alloy material of the tubular cracking furnace tube, the reaction temperature of the tubular cracking furnace generally does not exceed 1100°C. This means that the cracking depth of the tubular cracking furnace cannot be further improved for a long period of time before a breakthrough in heat-resistant materials is achieved;

[0004] (2) The tubular cracking furnace has a small diameter and low operating pressure. Usually, the density of the raw gas is very low, which also limits the operating capacity of the tubular cracking furnace. As the cracking device becomes larger and larger, multiple tubular cracking furnaces are usually required, which not only increases the floor space and construction investment, but also brings great challenges to safety management.

[0005] (3) The heating method adopted by the tubular cracking furnace is that the fuel burns in the burner to generate high-temperature gas and indirectly exchanges heat through the cracking furnace tube. Although the heat in the high-temperature gas is recovered through the convection section, more than 5% of the heat generated by the fuel combustion is still not effectively utilized;

[0006] (4) The combustion aid used in the tubular cracking furnace is generally air. During the combustion process of mixing with fuel, it is inevitable to produce NO x Flue gas containing pollutants such as chlorine and chlorine is currently directly discharged into the atmosphere, causing environmental pollution. Summary of the invention

[0007] In order to solve the problems existing in the existing cracking technology, such as the inability to further increase the cracking temperature, shorten the residence time, the limited scale of a single cracking furnace, and the insufficient utilization of the heat generated by fuel combustion, the object of the present invention is to provide a conical cracking reactor, a hydrocarbon cracking method and a reaction system.

[0008] To achieve the above-mentioned purpose, the present invention provides a conical cracking reactor, which includes a conical reactor body and a quench heat exchanger connected to the lower end of the conical reactor body, the top of the conical reactor body is provided with at least one cracking raw material inlet, and the side wall of the conical reactor body is provided with at least one high-temperature flue gas inlet.

[0009] In the conical cracking reactor of the present invention, the cracking raw material enters the conical cracking reactor through the nozzle, and undergoes multi-stage mixing and heat exchange with the high-temperature gas from the high-temperature and high-pressure combustion chamber, and the cracking reaction occurs quickly. Among them, the size of the conical reactor body from the feed end to the quencher (i.e., along the material flow direction) becomes narrower, and the conical design of the reactor body can speed up the flow rate of the cracking gas, thereby reducing the reaction residence time and reducing the occurrence of coking.

[0010] In the above-mentioned conical cracking reactor, preferably, the side wall of the conical reactor body is provided with at least two high-temperature flue gas inlets spaced apart along the reactor diameter. The temperature of multiple high-temperature flue gas inlets can continuously provide heat for the cracking reaction, which is conducive to the cracking reaction. The arrangement structure needs to be distributed in sequence from the raw material inlet to the product outlet along the reactor diameter.

[0011] In the above-mentioned conical cracking reactor, preferably, the conical reactor body and the quench heat exchanger are connected by a reducing structure; the reducing structure is preferably a Venturi connecting section. The setting of the reducing structure can ensure a higher cracking gas flow rate in the conical cracking reactor, shorten the reaction residence time, and relatively evenly distribute the cracking gas, thereby enhancing the heat exchange effect of the quench heat exchanger.

[0012] In the above-mentioned conical cracking reactor, preferably, a cracking product outlet is provided at the bottom of the quench heat exchanger.

[0013] In the above-mentioned conical cracking reactor, preferably, the quench heat exchanger is a partition heat exchanger, preferably a shell and tube heat exchanger.

[0014] The present invention also provides a hydrocarbon cracking method, which comprises: directly contacting the cracking raw material with the high-temperature flue gas at a temperature of 1000-1300°C and a pressure of 1-6Mpa to carry out a cracking reaction, and then rapidly cooling to obtain a cracking product; wherein the cracking reaction and rapid cooling are carried out in the above-mentioned conical cracking reactor.

[0015] Different from the convection heat exchange and radiation heat exchange of the tubular cracking furnace in the prior art, the hydrocarbon cracking method of the present invention allows the cracking raw material and the high-temperature flue gas to be directly mixed and contacted in the reactor for heat exchange, and the heat energy in the high-temperature flue gas is utilized to the maximum extent. The theoretical energy utilization efficiency is 100%, and the cracking reaction temperature is guaranteed to be maintained at a high level. In addition, in the cracking reaction of the hydrocarbon cracking method of the present invention, the pressure in the reactor is pressurized by the liquid raw material from the outside of the boundary area through the raw material tank bottom pump, and the liquid feed pressure can be adjusted according to the feed liquid combination and properties. Therefore, the cracking raw material and the high-temperature flue gas are directly mixed and contacted during the cracking reaction to maintain a higher reaction pressure. At the same time, accompanied by a higher cracking reaction pressure, the generated cracking product also has a higher pressure, which can greatly reduce the compression energy consumption of the cracking product in the subsequent separation treatment. In the present invention, the hydrocarbon cracking method can provide pressure through the upstream raw material pressure, and the downstream tower and other equipment help to achieve pressure stability.

[0016] In the above hydrocarbon cracking method, preferably, the hydrocarbon cracking method further comprises: cooling the cracked gas to 150-350° C. again and then fractionating it to obtain heavy oil and light components.

[0017] In the above hydrocarbon cracking method, preferably, the hydrocarbon cracking method further comprises: optionally compressing the light component and then performing CO 2 Recycle and process to obtain cracking gas.

[0018] In the above hydrocarbon cracking method, preferably, the high-temperature flue gas is obtained by burning a mixture of fuel and an oxidant, and the temperature of the high-temperature flue gas is 1000-1300°C and the pressure is 1-6Mpa. If the pressure of the light component is higher than that of CO 2 The recovered air pressure standard value does not need to be compressed, which can greatly save compression energy.

[0019] In the above hydrocarbon cracking method, preferably, the fuel is a gaseous fuel or a liquid fuel, the gaseous fuel may be ethane, propane or natural gas, and the liquid fuel may be gasoline or diesel; the combustion improver is pure oxygen, oxygen-enriched oxygen or air, more preferably pure oxygen. In the hydrocarbon cracking method of the present invention, the fuel and the combustion improver are controlled by calculating and setting a ratio to ensure that the high-temperature gas does not contain oxygen (i.e., the fuel is completely burned) on the one hand to avoid safety problems or consumption of downstream raw materials, and on the other hand to control the temperature of the high-temperature gas after combustion.

[0020] In the above hydrocarbon cracking method, preferably, the hydrocarbon cracking method rapidly cools the product to 300-600° C. to prevent secondary reactions of the cracking product.

[0021] In the above hydrocarbon cracking method, preferably, the cooling medium used for rapid cooling is saturated cooling water provided by the steam drum, and the saturated cooling water used for rapid cooling quickly removes heat from the cracked gas through rapid vaporization; the saturated cooling water rapidly cools the cracked product and then vaporizes into saturated steam and returns to the steam drum.

[0022] In the above hydrocarbon cracking method, preferably, the hydrocarbon cracking method further comprises exchanging heat between the cracking product and an external cooling medium, and the cooling medium after the heat exchange enters the steam drum to form the saturated cooling water.

[0023] In the above hydrocarbon cracking method, preferably, the hydrocarbon cracking method further comprises: using part of the heavy oil to preheat the cracking feedstock, and then cooling the cracking product; preferably, the hydrocarbon cracking method further comprises recovering heat from the heavy oil.

[0024] In the above hydrocarbon cracking method, preferably, the cracking raw materials can be various raw materials such as ethane, liquefied gas, naphtha, diesel, tail oil, crude oil, etc., which mainly come from refineries and can also be oil field resources.

[0025] In the above hydrocarbon cracking method, preferably, the hydrocarbon cracking method comprises:

[0026] The preheated cracking raw material is directly contacted with the high-temperature flue gas at a temperature of 1000-1300°C and a pressure of 1-6Mpa to carry out a cracking reaction, and then the reactant is rapidly cooled to 300-600°C to obtain a cracking product; wherein the cracking reaction and rapid cooling are carried out in the above-mentioned conical cracking reactor;

[0027] The cracked gas is cooled again and fractionated to obtain heavy oil and light components; the light components are optionally compressed and then CO 2 Recycle and process to obtain cracking gas.

[0028] The present invention also provides a hydrocarbon cracking reaction system, which comprises the above-mentioned conical cracking reactor and a combustion chamber, wherein the combustion chamber is provided with one or more flue gas channels, and the flue gas channels are respectively connected to the high-temperature flue gas inlets of the conical cracking reactor.

[0029] In the above hydrocarbon cracking reaction system, preferably, the cross-sectional areas of the flue gas channels are different. The flue gas channel pipe or the high-temperature gas channel constructed of fire-resistant and pressure-resistant materials. When the combustion chamber is provided with multiple flue gas channels, each flue gas channel is connected to the conical cracking reactor at intervals to ensure that the temperature in the cracking reactor is relatively constant, and at the same time, the cross-sectional areas (inner diameters) of each flue gas channel can be different to ensure reasonable distribution of the high-temperature gas flow.

[0030] In the above-mentioned hydrocarbon cracking reaction system, preferably, the hydrocarbon cracking reaction system also includes a steam drum, and the outer wall of the flue gas channel is also provided with a heat remover; wherein the saturated liquid outlet of the steam drum is connected to the heat exchange medium inlet of the quenching heat exchanger of the conical cracking reactor, the heat exchange medium outlet of the quenching heat exchanger is connected to the saturated steam inlet of the steam drum, and the steam outlet of the steam drum is connected to the heat remover of the combustion chamber.

[0031] In the above hydrocarbon cracking reaction system, the drum feed is boiler feed water heated by a heat recovery heat exchanger, the cooling medium in the drum (which can be boiler feed water) is transported to the quench heat exchanger, the vaporized saturated steam returns to the drum, and then is heated by a heat extractor, and the superheated steam is sent to the downstream device as a product. In the present invention, the saturated steam is heated to superheated steam, the temperature of the flue can be adjusted, and the raw material cracking reaction is easier to control. In addition, the superheated steam can be used as a turbine driving power for the compressor of the downstream device, which is beneficial to reduce the overall energy consumption of the whole plant.

[0032] In the above hydrocarbon cracking reaction system, preferably, the combustion chamber is provided with a fuel inlet and an oxidant inlet.

[0033] In the above hydrocarbon cracking reaction system, preferably, the combustion chamber is further provided with a temperature-adjusting steam inlet. The temperature-adjusting steam inlet is normally closed and is enabled when the high-temperature gas temperature is too high to quickly reduce the temperature of the high-temperature gas, so that the operating pressure of the high-temperature and high-pressure combustion chamber can be between 1-6Mpa and the operating temperature can be between 1000-1300°C.

[0034] In the above hydrocarbon cracking reaction system, preferably, the hydrocarbon cracking reaction system further comprises a fractionation tower, the fractionation tower is provided with an inlet, a cracking gas outlet and a heavy oil outlet, and the cracking product outlet of the quench heat exchanger is connected to the inlet of the fractionation tower.

[0035] The primary distillation tower can be a single tower or a multi-tower structure. The cracking products are further cooled in the primary distillation tower to recover the heat therein and achieve preliminary separation at the same time. The separated cracking gas enters the downstream device. A part of the heavy oil is used as the heat source of the raw material preheater to heat or gasify the cracking raw material. After cooling, it enters the temperature controller as a cold source to mix with the cracking products to cool them down. The other part is sent to the heavy oil heat exchanger for heat recovery.

[0036] In the above hydrocarbon cracking reaction system, preferably, the hydrocarbon cracking reaction system further comprises a heavy oil heat exchanger for recovering the heat of the heavy oil. The heavy oil heat exchanger may be single or multiple, and its purpose is to recover the heat in the heavy oil produced by the primary distillation tower to improve the heat utilization rate.

[0037] In the above-mentioned hydrocarbon cracking reaction system, preferably, the pipeline between the cracking product outlet of the quench heat exchanger and the inlet of the distillation tower passes through a heat recovery heat exchanger and a temperature controller in sequence; the cooling medium channel of the heat recovery heat exchanger is connected to the liquid inlet of the steam drum, and the heating medium inlet of the temperature controller is connected to the heavy oil outlet.

[0038] The heat recovery heat exchanger is used to achieve heat exchange between the cracking products and the external cooling medium. Using the heat recovery heat exchanger to cool the cracking products can reduce the occurrence of secondary reactions on the one hand, and absorb the heat in the cracking products through boiler feed water on the other hand to achieve the purpose of producing more steam and improve heat utilization efficiency.

[0039] The temperature controller further reduces the temperature of the cracking product by spraying heavy oil.

[0040] In the above hydrocarbon cracking reaction system, the heat recovery heat exchanger uses boiler feed water from outside as the medium to recover the remaining heat in the cracking product after passing through the quench heat exchanger to improve the heat utilization rate, and by increasing the internal energy of the boiler feed water, more saturated steam is generated for downstream devices.

[0041] In the above hydrocarbon cracking reaction system, preferably, the hydrocarbon cracking reaction system further comprises a feedstock preheater, wherein the heating medium channel of the feedstock preheater is connected to the heavy oil outlet. The feedstock preheater is used to realize heat exchange between the cracking feedstock and the heavy oil.

[0042] In the above hydrocarbon cracking reaction system, preferably, the hydrocarbon cracking reaction system comprises: a feed preheater, a high temperature and high pressure combustion chamber, a heat remover, a conical cracking reactor, a steam drum, a heat recovery heat exchanger, a temperature controller, a primary fractionation tower and a heavy oil heat exchanger;

[0043] The conical cracking reactor comprises a conical reactor body, and a quench heat exchanger connected to the lower end of the conical reactor body through a venturi connection section, the top of the conical reactor body is provided with at least one cracking raw material inlet, the side wall of the conical reactor body is provided with one or more high-temperature flue gas inlets, and the bottom of the quench heat exchanger is provided with a cracking product outlet;

[0044] The high temperature and high pressure combustion chamber is provided with one or more flue gas channels, and the flue gas channels are respectively connected to the high temperature flue gas inlet of the conical cracking reactor; the high temperature and high pressure combustion chamber is also provided with a fuel inlet, an oxidant inlet, and a temperature regulating steam inlet, and the heat removal device is arranged on the outer wall of the high temperature and high pressure combustion chamber;

[0045] The drum is provided with a liquid inlet, a saturated liquid outlet, a saturated steam inlet and a steam outlet, the saturated liquid outlet of the drum is connected to the heat exchange medium inlet of the quench heat exchanger of the conical cracking reactor, the heat exchange medium outlet of the quench heat exchanger is connected to the saturated steam inlet of the drum, and the steam outlet of the drum is connected to the heat remover of the combustion chamber;

[0046] The fractionation tower is provided with an inlet, a cracked gas outlet and a heavy oil outlet; the cracked product outlet of the quench heat exchanger is connected to the inlet of the fractionation tower; the pipeline between the cracked product outlet of the quench heat exchanger and the inlet of the fractionation tower passes through the heat recovery heat exchanger and the temperature controller in sequence; the cooling medium channel of the heat recovery heat exchanger is connected to the liquid inlet of the drum, and the heating medium inlet of the temperature controller is connected to the heavy oil outlet;

[0047] The heating medium channel of the raw material preheater and the heavy oil heat exchanger are respectively connected to the heavy oil outlet.

[0048] In the above hydrocarbon cracking reaction system, preferably, the hydrocarbon cracking reaction system is used to implement the above hydrocarbon cracking method.

[0049] The technical solution provided by the present invention has the following beneficial effects:

[0050] (1) The present invention directly mixes the high-temperature flue gas generated in the combustion chamber with the raw material for heat exchange and generates a cracking reaction, which can increase the cracking reaction temperature and thus improve the cracking reaction depth, while maximally utilizing the heat energy of fuel combustion (theoretical energy utilization efficiency is 100%);

[0051] (2) The operating pressure of the cracking reactor in the present invention breaks the limitation of the traditional tubular cracking furnace, and the cracking reaction can be carried out within 1-7Mpa. The cone-shaped cracking reactor greatly shortens the reaction residence time and prevents the problem of coking under high pressure conditions. At the same time, along with the higher cracking reaction pressure, the generated cracking products also have a higher pressure, which can greatly reduce the compression energy consumption of the cracking products in the subsequent separation treatment. (3) The present invention directly mixes the high-temperature gas with the cracking raw material for cracking. The carbon dioxide, carbon monoxide, water, etc. in the high-temperature gas can act as inert gases to reduce the reaction hydrocarbon partial pressure, so as to facilitate the cracking reaction. Compared with the traditional tubular cracking furnace, a large amount of dilution steam can be saved.

[0052] (4) The present invention adopts a segmented design between the high-temperature and high-pressure combustion chamber and the cracking reactor, and the two are connected only by a flue gas channel, thereby avoiding the safety risk of direct contact between the open flame in the combustion chamber and the raw materials in the cracking reactor; at the same time, multiple channels are discretely distributed on the cracking reactor, which can ensure the relative constancy of the reaction temperature of the cracking reactor to the greatest extent and ensure the depth of the cracking reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 This is a schematic flow diagram of a hydrocarbon cracking reaction system according to Example 2 of the present invention, which includes the conical cracking reactor of Example 1.

[0054] Description of Figure Numbers:

[0055] 01-high temperature and high pressure combustion chamber, 02-heat extractor, 03-connecting channel, 04-cracking reactor, 05-Venturi connecting section, 06-quenching heat exchanger, 07-heat recovery heat exchanger, 08-steam drum, 09-temperature controller, 10-primary fractionation tower, 11-raw material preheater, 12-heavy oil heat exchanger;

[0056] 001-cracking raw materials, 002-fuel, 003-combustion aid, 004-high-temperature flue gas, 005-cracking products, 006-heavy oil, 007-cracking gas, 008-boiler feed water, 009-saturated boiler feed water, 010-saturated steam, 011-superheated steam. DETAILED DESCRIPTION

[0057] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be construed as limiting the applicable scope of the present invention.

[0058] Example 1

[0059] This embodiment provides a conical pyrolysis reactor, such as Figure 1 As shown, it includes a conical reactor body 04, and a quench heat exchanger 06 connected to the lower end of the conical reactor body through a venturi connecting section 05, the top of the conical reactor body 04 is provided with at least one cracking raw material inlet, and the side wall of the conical reactor body 04 is provided with a plurality of spaced high-temperature flue gas inlets; the bottom of the quench heat exchanger 06 is provided with a cracking product outlet.

[0060] Example 2

[0061] This embodiment provides a hydrocarbon cracking reaction system, such as Figure 1 As shown, the hydrocarbon cracking reaction system comprises: a high-temperature and high-pressure combustion chamber 01, a heat remover 02, a conical cracking reactor of Example 1, a heat recovery heat exchanger 07, a steam drum 08, a temperature controller 09, a fractionating tower 10, a raw material preheater 11 and a heavy oil heat exchanger 12;

[0062] The high temperature and high pressure combustion chamber 01 is provided with one or more flue gas channels 03, and the flue gas channels 03 are respectively connected to the high temperature flue gas inlet of the conical cracking reactor; the high temperature and high pressure combustion chamber 01 is also provided with a fuel inlet, an oxidant inlet, and a temperature regulating steam inlet, and the heat removal device 02 is arranged on the outer wall of the flue gas channel 03;

[0063] The drum 08 is provided with a liquid inlet, a saturated liquid outlet, a saturated steam inlet and a steam outlet. The saturated liquid outlet of the drum 08 is connected to the heat exchange medium inlet of the quench heat exchanger 06 of the conical cracking reactor. The heat exchange medium outlet of the quench heat exchanger 06 is connected to the saturated steam inlet of the drum 08. The steam outlet of the drum 08 is connected to the heat remover 02.

[0064] The fractionation tower 10 is provided with an inlet, a cracked gas outlet and a heavy oil outlet. The cracked product outlet of the quench heat exchanger 06 is connected to the inlet of the fractionation tower 10. The pipeline between the cracked product outlet of the quench heat exchanger 06 and the inlet of the fractionation tower 10 passes through the heat recovery heat exchanger 07 and the temperature controller 09 in sequence; the cooling medium channel of the heat recovery heat exchanger is connected to the liquid inlet of the steam drum 08, and the heating medium inlet of the temperature controller 09 is connected to the heavy oil outlet; the heating medium channel of the raw material preheater 11 and the heavy oil heat exchanger 12 are respectively connected to the heavy oil outlet.

[0065] Example 3

[0066] This embodiment provides a hydrocarbon cracking method, which is implemented using the hydrocarbon cracking reaction system of embodiment 2. The hydrocarbon cracking method includes the following steps:

[0067] S1: The fuel 002 and the combustion aid 003 are completely burned and released in the high-temperature and high-pressure combustion chamber 01 to generate high-temperature flue gas 004 with a temperature of 1300°C and a pressure of 5Mpa. The high-temperature flue gas 004 enters the conical cracking reactor through the flue gas channel 03; at the same time, when the temperature of the high-temperature flue gas 004 is too high, temperature-adjusting steam is introduced to cool it down;

[0068] S2: The cracking raw material 001 is preheated or gasified by the raw material preheater 11 and then enters the conical reactor body 04 of the conical cracking reactor, where it is directly mixed with the high-temperature flue gas 004 from the high-temperature and high-pressure combustion chamber 01 for heat exchange, and a cracking reaction occurs in a very short time (millisecond level). The cracking reaction temperature is 1300°C and the pressure is 5Mpa. The resulting product enters the quenching heat exchanger 06 through the Venturi connecting section 05 and is quenched to 400°C to inhibit the occurrence of secondary reactions, thereby obtaining the cracking product 005. The quenching heat exchanger 06 uses the saturated boiler feed water 009 from the steam drum 08 as the cooling medium, and the saturated steam 010 from the quenching heat exchanger 06 is sent back to the steam drum 08, and is heated by the de-heater 02 to form superheated steam 011 and sent to downstream users.

[0069] S3: The cracking products are cooled to 170-300°C through the heat recovery heat exchanger 07 and the temperature controller 09 in turn, and then enter the primary distillation tower 10 with a single-tower or double-tower structure for fractionation to obtain light components and heavy oil; wherein, the heat recovery heat exchanger 07 uses boiler feed water from the outside as a cooling medium to cool the cracking products, and then the boiler feed water enters the steam drum; a part of the heavy oil is used as a heat source for the raw material preheater 11 to heat or gasify the cracking raw material, and after cooling, it enters the temperature controller 07 to mix with the cracking products to cool it, and then returns to the primary distillation tower 10, and the other part is sent to the heavy oil heat exchanger 12 for heat recovery and then returns to the primary distillation tower 10.

[0070] S4: The light component is optionally compressed to 5Mpa, and then CO 2 Recycling and processing to obtain cracking gas products; if the pressure of the light component is higher than that of CO 2 The recovered air pressure standard value does not need to be compressed, which can greatly save compression energy.

[0071] The hydrocarbon cracking method of this embodiment saves 5-10% of heat energy and 40-60% of total compression energy consumption, and the reaction residence time can be reduced to 1-2 milliseconds, which can effectively inhibit coking and extend the coke removal cycle by 20-30%.

Claims

1. A conical cracking reactor, which is used in a hydrocarbon cracking reaction system, the conical cracking reactor comprising a conical reactor body and a quench heat exchanger connected to the lower end of the conical reactor body, the top of the conical reactor body is provided with at least one cracking raw material inlet, and the side wall of the conical reactor body is provided with at least one high-temperature flue gas inlet; in, The conical reactor body and the quench heat exchanger are connected via a reducing structure, which is a venturi connecting section; a cracking product outlet is provided at the bottom of the quench heat exchanger, and the quench heat exchanger is a partition-type heat exchanger.

2. The conical pyrolysis reactor according to claim 1, wherein: The side wall of the conical reactor body is provided with at least two high-temperature flue gas inlets which are distributed at intervals along the reactor diameter.

3. The conical pyrolysis reactor according to claim 1, wherein: The quench heat exchanger is a shell and tube heat exchanger.

4. A hydrocarbon cracking method, comprising: The cracking raw material is directly contacted with the high-temperature flue gas at a temperature of 1000-1300°C and a pressure of 1-6Mpa to carry out a cracking reaction, and then the temperature is rapidly cooled to obtain a cracking product; wherein the cracking reaction and rapid cooling are carried out in the conical cracking reactor described in any one of claims 1-3.

5. The hydrocarbon cracking method according to claim 4, wherein: The hydrocarbon cracking method further comprises: cooling the cracking product to 170-300° C. again and then fractionating it to obtain heavy oil and light components.

6. The hydrocarbon cracking method according to claim 5, wherein: The hydrocarbon cracking method further comprises: optionally compressing the light component and then performing CO2 recovery processing to obtain cracking gas.

7. The hydrocarbon cracking method according to claim 4, wherein: The high-temperature flue gas is obtained by mixing and burning a fuel and a combustion-supporting agent. The temperature of the high-temperature flue gas is 1000-1300° C., and the reaction pressure is 1-6Mpa.

8. The hydrocarbon cracking method according to claim 4, wherein: The hydrocarbon cracking method rapidly cools the product to 300-600°C.

9. The hydrocarbon cracking method according to claim 8, wherein: The cooling medium used for rapid cooling is saturated cooling water provided by the steam drum; the saturated cooling water rapidly cools the cracking products, then vaporizes into saturated steam and returns to the steam drum.

10. The hydrocarbon cracking method according to claim 9, wherein: The hydrocarbon cracking method further includes exchanging heat between the cracking product and an external cooling medium, and the cooling medium after the heat exchange enters the steam drum to form the saturated cooling water.

11. The hydrocarbon cracking method according to claim 5, wherein: The hydrocarbon cracking method further includes: using part of the heavy oil to preheat the cracking raw material, and then cooling the cracking product; and further includes recovering heat from the heavy oil.

12. A hydrocarbon cracking reaction system, comprising the conical cracking reactor and a combustion chamber according to any one of claims 1 to 3, wherein the combustion chamber is provided with one or more flue gas channels, and the flue gas channels are respectively connected to the high-temperature flue gas inlets of the conical cracking reactor.

13. The hydrocarbon cracking reaction system according to claim 12, wherein: The hydrocarbon cracking reaction system also includes a steam drum, and the outer wall of the flue gas channel is also provided with a heat remover; wherein the saturated liquid outlet of the steam drum is connected to the heat exchange medium inlet of the quench heat exchanger of the conical cracking reactor, the heat exchange medium outlet of the quench heat exchanger is connected to the saturated steam inlet of the steam drum, and the steam outlet of the steam drum is connected to the heat remover of the combustion chamber.

14. The hydrocarbon cracking reaction system according to claim 12, wherein: The combustion chamber is provided with a fuel inlet and an oxidant inlet.

15. The hydrocarbon cracking reaction system according to claim 14, wherein: The combustion chamber is also provided with a temperature-adjusting water vapor inlet.

16. The hydrocarbon cracking reaction system according to claim 13, wherein: The hydrocarbon cracking reaction system further comprises a fractionation tower, which is provided with an inlet, a cracking gas outlet and a heavy oil outlet, and the cracking product outlet of the quench heat exchanger is connected to the inlet of the fractionation tower.

17. The hydrocarbon cracking reaction system according to claim 16, wherein: The pipeline between the cracking product outlet and the fractionation tower inlet passes through a heat recovery heat exchanger and a temperature controller in sequence; the cooling medium outlet of the heat recovery heat exchanger is connected to the liquid inlet of the drum, and the heating medium inlet of the temperature controller is connected to the heavy oil outlet.

18. The hydrocarbon cracking reaction system according to claim 16, wherein: The hydrocarbon cracking reaction system further comprises a raw material preheater, wherein a heating medium channel of the raw material preheater is connected to the heavy oil outlet.

19. The hydrocarbon cracking reaction system according to any one of claims 12 to 18, wherein: The hydrocarbon cracking reaction system is used to implement the hydrocarbon cracking method according to any one of claims 4 to 11.

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