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CN-120718684-B - Method and system for hydrogenating heavy inferior oil by adopting mesoscale reaction

CN120718684BCN 120718684 BCN120718684 BCN 120718684BCN-120718684-B

Abstract

The invention relates to the technical field of petrochemical industry and discloses a method and a system for hydrogenating heavy inferior oil by adopting a mesoscale reaction, wherein the method comprises the following steps of (1) preheating the heavy inferior oil, and then introducing hydrogen-rich acidic gas to conduct hydrogenolysis association; the method comprises the steps of (1) mixing the slurry with saturated hydrogen in a feeding pipeline, then introducing the mixture into a medium reactor from the bottom, wherein the medium reactor is provided with an initial zone for introducing initial hydrogen, a reaction zone for introducing reaction hydrogen and a time delay zone for introducing delayed hydrogen from bottom to top, performing hydrogenation reaction to obtain hydrogenated slurry, (3) separating the hydrogenated slurry from the slurry to obtain supernatant, and (4) separating the supernatant under reduced pressure to obtain diesel oil and wax oil respectively. The invention can realize the targeted conversion of supermolecular asphaltene and residual oil, fundamentally slow down the generation and polymerization of coke, and solve the problems of full load and long-period operation of the device.

Inventors

  • XUE KUANRONG
  • FENG WEIQUAN
  • QIAN HUIQIN
  • WANG JUNWEI
  • YU RUI
  • YANG HONGQUAN

Assignees

  • 浙江东江绿色石化技术创新中心有限公司

Dates

Publication Date
20260512
Application Date
20250529

Claims (10)

  1. 1. The method for hydrogenating heavy inferior oil by adopting the mesoscale reaction is characterized by comprising the following steps of: (1) Preheating heavy inferior oil, introducing hydrogen-rich acid gas for hydrogenolysis, wherein the hydrogen-rich acid gas comprises hydrogen sulfide and hydrogen, and the volume flow ratio of the hydrogen-rich acid gas to the heavy inferior oil is 100:650-700, and then introducing a catalyst precursor for activation and dispersion, wherein the catalyst precursor is molybdenum isooctanoate to obtain slurry, and the introducing amount of the catalyst precursor is such that the mass ratio of the catalyst in the slurry in the step (1) is 2100-4500ppm; (2) Mixing the slurry with 385-395 ℃ saturated hydrogen in a feeding pipeline, introducing the mixture into a dielectric reactor from the bottom, wherein the dielectric reactor is provided with an initial region for introducing 495-505 ℃ initial hydrogen, a reaction region for introducing 495-505 ℃ reaction hydrogen and a delay region for introducing 300-320 ℃ delay hydrogen from bottom to top, the volume flow ratio of the saturated hydrogen to the initial hydrogen to the reaction hydrogen to the delay hydrogen is 1:4-6:11-13:2-4, carrying out hydrogenation reaction, and the total time of the hydrogenation reaction is 300-360min, wherein the residence reaction time accounts for 10-15%, 50-60% and 30-35% in the initial region, the reaction region and the delay region respectively, thus obtaining hydrogenation slurry; (3) Separating the hydrogenated slurry to obtain a supernatant; (4) And (3) carrying out decompression separation on the supernatant to obtain diesel oil and wax oil respectively.
  2. 2. The process for hydrogenating heavy inferior oil using a mesoscale reaction according to claim 1, wherein in step (1), the preheating temperature is 350-360 ℃.
  3. 3. The process for hydrogenating heavy inferior oil using a mesoscale reaction of claim 1 wherein in step (2) the volume flow ratio of slurry to saturated hydrogen is 15:10-12.
  4. 4. The method for hydrogenating heavy inferior oil by adopting a mesoscale reaction according to claim 1, wherein in the step (2), the initial zone, the reaction zone and the time delay zone respectively account for 10-15%, 50-60% and 30-35% of the volume of the mesoscale reactor.
  5. 5. The process for hydrogenating heavy inferior oil using a mesoscale reaction according to any of claims 1 to 4, wherein in step (3), said slurry separation comprises a high pressure momentum separation and a low pressure momentum separation carried out in sequence.
  6. 6. The method for hydrogenating heavy inferior oil by adopting a mesoscale reaction according to claim 5, wherein the high-pressure momentum separation comprises the steps of introducing hydrogenation slurry and quenching oil at 175-190 ℃ into a high-pressure momentum separator, introducing disturbance-increasing hydrogen into the lower part of the separator, and separating to obtain hydrogen-rich oil gas and solid-liquid phase mixed slurry.
  7. 7. The method for hydrogenating heavy inferior oil by adopting a mesoscale reaction according to claim 6, wherein the low-pressure momentum separation comprises the steps of introducing solid-liquid phase mixed slurry into a low-pressure momentum separator for separation to obtain a heavy component, and carrying out flash evaporation and cyclone separation on the heavy component to obtain a supernatant.
  8. 8. The method for hydrogenating heavy inferior oil by adopting a mesoscale reaction according to claim 1, wherein in the step (4), the pressure reduction separation is carried out in a solid-liquid pressure reduction separation tower, the solid-liquid pressure reduction separation tower is respectively an upper narrow tower section, a middle wide tower section and a lower cone section from top to bottom, the tower top temperature is 52-62 ℃, the tower bottom temperature is 305-315 ℃, the tower pressure is-0.075 MPa to-0.065 MPa, a diesel oil product is extracted from the upper part, and a wax oil product is extracted from the middle part.
  9. 9. The method for hydrogenating heavy inferior oil by adopting a mesoscale reaction according to claim 7, wherein the heavy slurry obtained after cyclone separation and the heavy slurry obtained after pressure reduction separation in the step (4) are returned to the step (1) as circulating slurry and introduced into the reactor together with the catalyst precursor for activation and dispersion.
  10. 10. The method for hydrogenating heavy inferior oil by adopting the mesoscale reaction according to claim 1, wherein the system for implementing the method comprises a raw oil initial reaction device, a mesoreactor, a slurry separation device and a decompression separation device which are sequentially connected, wherein the raw oil initial reaction device comprises a desorption preheater, a hydrogenolysis desorption reactor and a deep activation reactor which are sequentially connected, the bottom of the mesoreactor is provided with a slurry inlet, the top of the mesoreactor is provided with a slurry outlet, the slurry inlet is communicated with the deep activation reactor through a feeding pipeline, a saturated hydrogen inlet is further arranged on the feeding pipeline, the mesoreactor comprises an initial zone, a reaction zone and a delay zone which are arranged from bottom to top, the initial zone is provided with an initial hydrogen inlet, the reaction zone is provided with a reaction hydrogen inlet, and the delay zone is provided with a delay hydrogen inlet.

Description

Method and system for hydrogenating heavy inferior oil by adopting mesoscale reaction Technical Field The invention relates to the technical field of petrochemical industry, in particular to a method and a system for hydrogenating heavy inferior oil by adopting a mesoscale reaction. Background The mainstream heavy oil hydrogenation technology includes four major categories, namely fixed bed, moving bed, ebullated bed and slurry bed (suspended bed). The fixed bed has strict requirements on the weight, sulfur content, metal content and conversion depth of raw materials, and the problems of large pressure drop, short period, high replacement cost and the like caused by the reasons of asphaltene flocculation sedimentation, easy coking and blocking of a bed layer and the like cannot be solved when the heavy and inferior oil is processed, and the heavy and inferior oil is started to shake along with the development of the electric automobile industry to attenuate the gasoline demand. The moving bed has few industrial applications, complex system equipment, higher investment and high running safety risk. The total conversion rate of the boiling bed is low, the stability of the asphalt core is poor, the system is easy to coke and block, the fault shutdown is frequent, the energy consumption is high, the difficulty of clean utilization of oil residues is high, and the marketization acceptance is reduced and is gradually ignored. Typical processes of slurry beds (suspended beds) comprise VCC, uniflex, EST and domestic coal and oil co-refining, direct coal liquefaction and other technologies, for example, publication number CN119286560A discloses a residual oil conversion process method and a reaction system, which have the problems of vortex temperature flying at the bottom of a reactor, easy separation of products, flocculation and aggregation of asphalt nuclei, short operation period, high failure rate of key equipment, high energy consumption of a device, high agent consumption, high methanation, poor raw material adaptability, low liquid yield of target products, accident safety risk disposal and the like, thereby influencing the economical efficiency, cleanliness, safety and reliability of the device. The marketed slurry bed (suspended bed) residuum hydrogenation technology comprises two processing units, a slurry reaction unit and a slurry fractionation unit. The device reactor in industrialization cannot completely solve the contradiction between the good thermal cracking reaction and the hydrogenation reaction and the contradiction between the single-molecule reaction and the double-molecule reaction. The vacuum tower system fails to break through the constraint of the inherent concept of rectification, and fails to solve the problems of entrainment and solid-liquid separation, so that the system has the defects of difficult multi-point coking operation, high hydrogen consumption, high agent consumption, low product yield, weak comprehensive economy, frustrated investment and enthusiasm, even if devices in operation have to be modified to increase standby vacuum towers to maintain operation in a cold switching mode, the important influences of short single-tower operation period, 6-8 days of cold switching reaction refund, 8-10 days of slurry restoration and the like still exist, the nominal design capacity of a final device can only be exerted by about 78 percent, and the key technology reaction core problem cannot be solved by the technical measure of temporary solution but the essential problems of influencing the production period and high-efficiency conversion of the device cannot be thoroughly eliminated. The mesoreaction is a heterogeneous mesoscale reaction shorthand. By mesoscale behavior is meant the complex spatiotemporal structure formed by a system consisting of a large number of units in a scale range between individual units and the global system. During the heterogeneous reaction, it is predominantly represented by the material structure or surface interface spatiotemporal scale from molecular scale to particle (including discrete units such as bubbles, droplets, and the like, hereinafter) scale, and the spatiotemporal scale of the heterogeneous structure formed from particle scale to reactor scale. The chemical reactions that occur therein (atomic molecular level) exhibit complex behavior under the influence of mass transfer diffusion (molecular group level) and flow (macroscopic statistical level). Disclosure of Invention In order to solve the technical problems, the invention provides a method and a system for hydrogenating heavy inferior oil by adopting a mesoscale reaction, which utilizes the mesoscale reaction to design a high-efficiency heavy inferior oil hydrogenation reactor, establishes a reaction dynamics and hydrodynamic model of three-region two-critical (gas, liquid and solid three-region; two-critical interface of solid, liquid and gas) and prepares the synergistic effect of par