WO2014117633A1 - 提高加氢装置氢气利用率的方法及装置 - Google Patents

提高加氢装置氢气利用率的方法及装置 Download PDF

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Publication number
WO2014117633A1
WO2014117633A1 PCT/CN2014/000029 CN2014000029W WO2014117633A1 WO 2014117633 A1 WO2014117633 A1 WO 2014117633A1 CN 2014000029 W CN2014000029 W CN 2014000029W WO 2014117633 A1 WO2014117633 A1 WO 2014117633A1
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WIPO (PCT)
Prior art keywords
gas
liquid
hot
separation
separator
Prior art date
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Ceased
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PCT/CN2014/000029
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English (en)
French (fr)
Inventor
杨强
许萧
卢浩
王朝阳
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East China University of Science and Technology
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East China University of Science and Technology
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Priority claimed from CN201310037577.5A external-priority patent/CN103071318B/zh
Priority claimed from CN201310239487.4A external-priority patent/CN103320161B/zh
Application filed by East China University of Science and Technology filed Critical East China University of Science and Technology
Priority to EP14746608.0A priority Critical patent/EP2952555A4/en
Priority to MX2015013413A priority patent/MX2015013413A/es
Priority to US14/764,178 priority patent/US20160038854A1/en
Publication of WO2014117633A1 publication Critical patent/WO2014117633A1/zh
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D19/00—Degasification of liquids
    • B01D19/0036—Flash degasification
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D19/00—Degasification of liquids
    • B01D19/0042—Degasification of liquids modifying the liquid flow
    • B01D19/0052—Degasification of liquids modifying the liquid flow in rotating vessels, vessels containing movable parts or in which centrifugal movement is caused
    • B01D19/0057—Degasification of liquids modifying the liquid flow in rotating vessels, vessels containing movable parts or in which centrifugal movement is caused the centrifugal movement being caused by a vortex, e.g. using a cyclone, or by a tangential inlet
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
    • B01D3/06—Flash distillation
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G31/00—Refining of hydrocarbon oils, in the absence of hydrogen, by methods not otherwise provided for
    • C10G31/06—Refining of hydrocarbon oils, in the absence of hydrogen, by methods not otherwise provided for by heating, cooling, or pressure treatment
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G31/00—Refining of hydrocarbon oils, in the absence of hydrogen, by methods not otherwise provided for
    • C10G31/10—Refining of hydrocarbon oils, in the absence of hydrogen, by methods not otherwise provided for with the aid of centrifugal force
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G45/00—Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G45/00—Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds
    • C10G45/02—Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds to eliminate hetero atoms without changing the skeleton of the hydrocarbon involved and without cracking into lower boiling hydrocarbons; Hydrofinishing
    • C10G45/14—Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds to eliminate hetero atoms without changing the skeleton of the hydrocarbon involved and without cracking into lower boiling hydrocarbons; Hydrofinishing with moving solid particles
    • C10G45/20—Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds to eliminate hetero atoms without changing the skeleton of the hydrocarbon involved and without cracking into lower boiling hydrocarbons; Hydrofinishing with moving solid particles according to the "fluidised-bed" technique
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G53/00—Treatment of hydrocarbon oils, in the absence of hydrogen, by two or more refining processes
    • C10G53/02—Treatment of hydrocarbon oils, in the absence of hydrogen, by two or more refining processes plural serial stages only
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/32—Hydrogen storage

Definitions

  • the present invention relates to the field of refining hydrocarbon oils with hydrogen, and more particularly to a method and apparatus for improving the hydrogen utilization rate of a hydrogenation unit by using inertial separation distribution technology, jet flashing and centrifugal degassing combined technology. Background of the invention
  • distillate hydrogenation process has been widely used in clean fuel production.
  • the distillate hydrogenation process is also widely used to obtain clean fuel.
  • the traditional hydrocarbon oil hydrogenation process requires a large amount of hydrogen to ensure a certain partial pressure of hydrogen. A small part of the hydrogen is consumed by the hydrogenation reaction, and most of it is recycled by the circulating hydrogen compressor.
  • the separation process of the reaction products of the medium and high pressure hydrogenation process usually has a cold high-sorting process and a hot high-sorting process.
  • the process of gas-liquid separation after all the reaction products pass through the air cooler is called cold high-sorting process; and all the reaction products are first subjected to gas-liquid separation at a certain temperature, and the flashed oil and gas is subjected to heat exchange and air cooling.
  • the process of separation is called the hot high score process.
  • the cold high score and hot high score processes have been widely used in domestic and international hydrogenation plants.
  • the core issue in the selection of cold high scores and hot high score processes is how to make economic comparisons between the two processes.
  • the advantages of the hot high-sorting process are: reducing the energy consumption of the device and reducing the cold-changing area; reducing the freezing phenomenon of the air cooler in the alpine region; and preventing the accumulation of the polycyclic aromatic hydrocarbons from blocking the high-pressure air cooler for the full-circulation process.
  • the high-temperature oil and gas separation system is increased, and the hydrogen loss is large, and the circulating hydrogen concentration is also slightly lower than the cold high-sorting process, resulting in a slight increase in the pressure of the entire reaction system.
  • the prerequisite for using a hot high-sort process is that the hydrogen contained in the low-gas separation must be efficiently recovered, and the hydrogen dissolved in the cold low- and oil-low oils is generally considered to be part of the hydrogen loss.
  • the hydrogen and the hydrogenated distillate are subjected to gas-liquid phase separation at a specific temperature and pressure of the hot high-pressure separator, and the separated helium is separated by gravity sedimentation; the hot high-pressure separator gas is pressurized by a circulating hydrogen compressor.
  • the liquid phase of the hot enthalpy separator is flashed under reduced pressure, and a low gas separation is released at a specific temperature and pressure of the hot low pressure separator.
  • the hydrogen content in the low gas separation is generally about 70%, and is separated by gravity sedimentation. This portion of the low gas is generally sent to the PSA unit as a hydrogen-rich gas to recover the hydrogen therein.
  • the pressure of the low-pressure separator of the medium-high pressure hydrogenation unit is designed to be 1. 2 ⁇ 3. 0 MPa (G), to ensure that the separated low-separation oil enters the fractionation tower by pressure, and the hydrogen content of the separation tower is separated. Low can not be recycled and is usually used as a fuel gas, and the utilization efficiency of hydrogen is low. Since the gas-liquid two-phase of the hot high-pressure separator and the hot low-pressure separator in the current hydrogenation high-intensity process usually adopts natural gravity sedimentation, as shown in Fig. 1, the inevitable part of the gas (mainly hydrogen) is tiny. The bubbles are present in the liquid phase and are sent to subsequent devices, causing partial loss of hydrogen. In addition, the hot low pressure separator uses a conventional flash-gravity sedimentation separation method, and the liquid phase contacts the surface due to a certain residence time. Smaller
  • the present invention provides a method and apparatus for improving the utilization of hydrogen in a hydrothermal high-dividing process.
  • the distillate oil, gas product and hydrogen are first subjected to preliminary gas-liquid separation under high pressure through an inertial separation distributor set at the inlet of the hot high-pressure separator to enhance gas separation efficiency, and the gas phase is subjected to cyclic hydrogen compression after cold high pressure and subsequent facilities.
  • the machine returns to the reaction system; the first step of the liquid phase is subjected to preliminary separation by jet flashing to release a part of low gas (mainly hydrogen), and the separated gas phase is divided into gas phase and liquid phase by gravity sedimentation method;
  • the gas dissolved in the hydrazine and some of the tiny bubbles are separated by the centrifugal degassing method of the second step, relying on the pressure gradient of the centrifugal degassing device (the radial section gradually decreases from the external to the internal pressure) and the centrifugal field, dissolved in the distillate
  • the gas is precipitated due to the decrease of the partial pressure of the pressure gradient field.
  • the part analyzes that the gas and the microbubbles are further separated under the centrifugal field; the gas phase is separated by the cyclone separation or coalescence separation to remove the carried droplets.
  • the device distillate oil to the follow-up facility.
  • the method device compensates for the deficiencies of the prior art and improves the recovery rate of hydrogen.
  • a method for improving hydrogen utilization rate in a hydrothermal high-dividing process comprising the following steps:
  • OlMPa OlMPa
  • the gas-liquid two phases separated by flashing are separated by gravity sedimentation
  • the separated liquid phase is subjected to a secondary degassing by means of a centrifugal degassing method by means of a swirling or centrifugal pressure gradient field.
  • the pressure difference in the pressure gradient field is 0.01 to 10 MPa, and the separated gas phase is from the upper portion. 6-5MPa, operating temperature is 170-240 ° C; the operating pressure is 0.
  • the apparatus for improving the hydrogen utilization rate in the hydrothermal high-concentration process comprises a hot high pressure separator provided with an inlet, a liquid phase outlet and a gas phase outlet, and a hot low pressure separation provided with an inlet, a liquid phase outlet and a gas phase outlet.
  • the liquid phase outlet of the hot high pressure separator is in communication with the inlet of the hot low pressure separator, and a jet flash separator is disposed at the inlet of the hot low pressure separator, the jet flash separator comprising at least one jet flash core tube
  • the low pressure separator is disposed at the outlet of the liquid phase and is provided with at least one centrifugal degassing core tube.
  • the centrifugal degassing core tube comprises a cavity, and the cavity is provided with a liquid gas inlet, a gas phase outlet and a liquid phase outlet, and the gas phase outlet 1 ⁇
  • the cavity is inserted into the cavity from the center of the cavity, the insertion depth is 0.1 to 3 times the maximum diameter of the cavity.
  • the inlet of the hot high-pressure separator is provided with at least one inertial separation distributor, and the inertial separation distributor includes a plurality of inertial separation distribution blades, an upper cover and a lower cover disposed on both sides, the inertial guide vane
  • the utility model comprises a straight line segment, a semicircle of the blade corner and a straight line segment, wherein the straight line segment is near one end of the box body; the plurality of inertial separation and distribution blades can be arranged in one layer or in a plurality of layers.
  • the upper cover or the lower cover of the inertial separation distributor adopts a self-feeding center line to an edge inclined manner, and the inclination angle is 3 to 60 degrees.
  • a gas-liquid separator is disposed at the vapor phase outlet of the hot high pressure separator or / and the gas phase outlet of the hot low pressure separator.
  • gas-liquid separator is a gas-liquid cyclone or a coalescing separator.
  • the hot low pressure separator comprises a plurality of jet flash core tubes, wherein the plurality of jet flash core tubes are connected in parallel in a radial cross section of the hot low pressure separator, and the liquid flow rate of the flash core tube can be increased by the jet 1-20 times larger.
  • a corresponding umbrella cloth dispenser is disposed at the outlet of the jet flash separator, and the surface area of the umbrella cloth is 1-30 times of the exit area of the jet flash core tube.
  • the hot low pressure separator comprises a plurality of the centrifugal degassing core tubes which are connected in parallel and uniformly disposed in a radial section of the hot low pressure separator. Further, the hot low pressure separator further comprises a partition plate dividing the hot low pressure separator into two chambers, the partition plate setting height is adapted to the height of the centrifugal degassing core tube to be centrifuged off The inlet of the gas core tube and the liquid phase outlet are separated into the two chambers.
  • the invention has the beneficial effects that: the invention firstly adopts the method of inertial separation and distribution to strengthen the gas-liquid separation and improve the hydrogen separation efficiency of the hot high pressure separator; secondly, the jet flashing and the liquid umbrella uniformizing technique are used to improve the flash degassing of the distillate oil.
  • Efficiency under the action of gravity field, firstly separate the distillate carrier gas and the dissolved gas released by the pressure drop, and then the gas dissolved under the operating pressure of the hot low pressure separator can not be effectively removed by flash evaporation method, and the flash separation is performed.
  • the fine bubbles dispersed in the distillate oil can not be effectively removed by gravity.
  • the secondary separation by the centrifugal degassing method is adopted.
  • the dissolved gas under the partial pressure depends on the pressure gradient field of the centrifugal liquid gas separation (radial section from the external to the internal pressure) Gradually reduced) Separation, the tiny bubbles entrained in the distillate oil are effectively removed by the centrifugal field.
  • FIG. 1-1 is a schematic view of a prior art process.
  • Figure 1-2 shows the flow chart of the existing device.
  • FIG. 2 is a schematic view of the process flow of the present invention.
  • FIG. 3 is a schematic flow chart of a device according to a first embodiment of the present invention.
  • FIG. 4 is a schematic flow chart of a device according to a second embodiment of the present invention.
  • Figure 5-1 is a top view of the inertial separation distributor of the hot high pressure separator inlet.
  • Figure 5-2 is a left side view of the inertial separation distributor of the hot high pressure separator inlet.
  • Figure 6-1 shows the structure of the centrifugal degassing core tube.
  • Figure 6-2 is a schematic view of the radial pressure of the centrifugal degassing core tube taken along the line A-A.
  • Figure 6-3 is a simulation diagram of the pressure gradient distribution of the radial section of the centrifugal degassing core tube.
  • FIG. 7 is a detailed view of the structure of the centrifugal degassing core tube. Symbol Description:
  • 1 is a hot high pressure separator; 1-1 is a hot high pressure inlet; 1-2 is an inertial separation distributor; 1-3 is a hot high pressure gas phase outlet; 1-4 is an outlet gas liquid separator; 1-5 hot high pressure liquid phase 2; is a hot low pressure separator; 2-1 is a jet flash separator; 2-1-1 is a jet flash core tube; 2-2 is an umbrella cloth dispenser; 2-3 is a centrifugal degassing device; 2-3-1 is a centrifugal degassing core tube; 2-4 is a partition plate; 2-5 is a gas-liquid separator; 2-6 is a hot low-pressure gas-phase outlet; 2-7 is a hot low-pressure inlet; Hot low pressure liquid phase outlet; 1-1- 1 is hot high pressure inlet pipe; 1-2-1 is inertial separation distribution blade; 1-2-2 is upper cover; 1-2- 3 is lower cover; 3 is Second hot low pressure separator.
  • 2-3-1-1-1 is a liquid-gas axial flow inlet; 2- 3- 1-1-2 is a liquid-gas tangential inlet; 2-3- 1-2 is a column cavity; 2- 3- 1- 3 is a cone cavity; 2-3-1-4 is a liquid phase outlet of the centrifugal degassing core tube; 2- 3-1- 5 inner cone; 2-3-1-6 is an overflow tube inverted cone thick wall; 2 -3-1-7 is the secondary liquid outlet; 2-3-1-8 is the annular slot, 2- 3- 1-9 is the injection secondary separation overflow pipe, 2-3-1-9-1 is The bell mouth, 2-3-1-9-2 is the first overflow pipe column cavity, 2-3-1-9-3 is the inverted cone connection cavity, and 2-3-1-9-4 is the second overflow.
  • the flow tube cavity, 2-3-1-9-5 is a cylinder.
  • the invention relates to a device for improving hydrogen recovery of a hydrogenation unit, comprising a hot high pressure separator provided with an inlet, a liquid phase outlet and a gas phase outlet, and a hot low pressure separator provided with an inlet, a liquid phase outlet and a gas phase outlet, the hot high pressure separation
  • the liquid phase outlet of the device is in communication with an inlet of the hot low pressure separator, and a jet flash separator is disposed at the inlet of the hot low pressure separator, the jet flash separator comprising at least one jet flash core tube;
  • the hot low pressure separator Provided before the liquid phase outlet is provided at least one centrifugal degassing core tube, the centrifugal degassing core tube comprises a cavity, wherein the cavity is provided with a liquid gas inlet, a gas phase outlet and a liquid phase outlet, the gas phase outlet is from the chamber The 1-3 times the maximum diameter of the cavity is inserted into the cavity.
  • the process for improving the hydrogen recovery of the hydrogenation unit of the present invention is as follows: After hydrogenation, the distillate oil, gas product and hydrogen are firstly separated by an inertial separation distributor set at the inlet of the hot rolling separator, and the pressure drop of the inertial separation distributor is 0. 0001 ⁇ 0.
  • OlMPa Secondly, secondary separation by gravity sedimentation, after separation and separation of the inertial separation distributor and cavity in the hot high pressure separator, the gas phase (cycle hydrogen and part of light distillate) is removed to the subsequent device, liquid phase ( The distillate oil and the dissolved gas are introduced into the hot low pressure separator; the distillate oil entering the hot low pressure separator is first separated by a jet flashing technique to the gas phase dissolved in the distillate oil, the pressure drop of the process is not more than 0.
  • the sedimentation separates the gas-liquid two phases separated by flashing, and the separated liquid phase is subjected to secondary degassing by means of a centrifugal degassing method by means of a swirling or centrifugal pressure gradient field, and the pressure difference in the pressure gradient field is 0. 01 ⁇ 10 MPa, after flash separation by jet flasher, gas phase (low gas separation, mainly hydrogen) to PSA recovery, liquid phase and dissolved gas and carried small gas To degassing centrifugal degasser secondary separation, after the liquid (distillate) from the lower portion of the apparatus, separated from the upper gas outlet to the vapor recovery PSA.
  • gas phase low gas separation, mainly hydrogen
  • the problem of low natural gravity separation and separation efficiency of the gas-liquid two-phase of the hot high pressure separator and the hot low pressure separator in the current hydrothermal high-concentration process can be significantly overcome, and a part of the gas (mainly hydrogen) is solved to be small.
  • the bubbles are present in the liquid phase, which is sent to the subsequent device, causing partial loss of hydrogen.
  • the conventional thermal low-pressure separator is overcome by the conventional flash-gravity sedimentation separation method, and the liquid is operated under a certain residence time.
  • the gas phase contact surface is small, causing a low flashing efficiency, causing a partial hydrogen loss problem.
  • the pressure of the hot low pressure separator is designed to be 1. 2 ⁇ 3. 0 MPa (G), the partial hydrogen is dissolved in the liquid phase, causing a part The problem of hydrogen loss.
  • the implementation of the invention improves the recovery of hydrogen, which brings benefits to the efficient and economical operation of the production plant of the enterprise.
  • a petrochemical hydrogenation unit adopts a hot high-sorting process, and the feed parameters of the hot high-pressure separator are as follows:
  • H2 concentration in the gas phase is 73.8946% (v)
  • H2S concentration is 1.8413% (v)
  • H2S in liquid phase The concentration of the H2S in the liquid phase is 0.134% (v)
  • the concentration of H2S in the liquid phase is 1. 3705% (V)
  • the concentration of H2S in the liquid phase is 0.132% (wt). .
  • the existing hydrogenation heat high pressure separation process is realized by the following steps. After hydrogenation, the distillate oil, gas product and hydrogen first enter the hot high pressure separator 1 to carry out gas at a certain temperature and pressure. The liquid is separated, the separation is carried out by gravity sedimentation, the separated gas phase is removed to the subsequent device, the liquid phase enters the hot low pressure separator 2 for flashing, and the flashed gas-liquid two phases are separated by gravity sedimentation, and the separated gas phase (low The gas is removed to the PSA for hydrogen recovery, and the liquid phase is followed by a desulfurization and fractionation unit.
  • the gas-liquid two phases usually adopt natural gravity sedimentation, so the inevitable part of the gas (mainly hydrogen) exists in the liquid phase as tiny bubbles, which are then sent to the subsequent device, causing part of the hydrogen gas. Loss;
  • the hot low-pressure separator adopts the traditional flash-gravity sedimentation separation method, and the liquid-vapor contact surface is small due to the residence time of a certain residence time, resulting in low flashing efficiency, resulting in partial hydrogen loss;
  • the pressure is designed to be 1. 2 ⁇ 3. 0 MPa (G). At this partial pressure, some hydrogen is also dissolved in the liquid phase, which also causes partial loss of hydrogen. Therefore, a more efficient method is needed to recycle this part of the hydrogen, which will bring benefits to the efficient and economic operation of the enterprise.
  • 1 to 2 are schematic views of a device and a flow chart thereof according to a first embodiment of the present invention, the device comprising a hot high pressure separator 1 provided with an inlet 1-1, a liquid phase 1-5 outlet and a gas phase outlet 1-3.
  • a hot low pressure separator 2 provided with an inlet 2-7, a liquid phase outlet 2-8 and a gas phase outlet 2-6, the liquid phase outlet 1-5 of the hot high pressure separator 1 is the same as the inlet 2 of the hot low pressure separator 7-phase communication
  • a hot flash separator inlet 2-7 is provided with a jet flash separator 2-1
  • the jet flash separator 2-1 comprises a plurality of jet flash core tubes 2-1-1, which are The jet flash core tubes 2-1-1 are connected in parallel and uniformly arranged in the radial section of the hot low pressure separator 2, and the liquid flow rate of the flash core tube can be increased by 1-20 times.
  • Each spray flash tube 21-1 is provided with a corresponding umbrella cloth 2-2 at the injection port, and the surface area of the umbrella cloth 2-2 is 1-1 of the outlet area of the jet flash tube. 30 times.
  • the hot low pressure separator 2 is provided with a plurality of centrifugal degassing core tubes 2-3 before the liquid phase outlet, and the plurality of centrifugal degassing core tubes 2-3 are connected in parallel and uniformly disposed in a radial section of the hot low pressure separator.
  • a gas-liquid separator 1-4 is disposed at the gas phase outlet of the hot high-pressure separator 1, and a gas-liquid separator 2-5 is disposed at the gas-phase outlet of the hot low-pressure separator 2, and the gas-liquid separators 1-4, 2-5 are gas Liquid swirl or coalescing separator.
  • the hot low pressure separator 2 further includes a partition plate 2-4 that divides the hot low pressure separator 2 into two chambers, which The height of the partition plate 2-4 is adapted to the height of the centrifugal degassing core tube 2-3 to separate the inlet and the liquid phase outlet of the centrifugal degassing core tube 2-3 into the two chambers.
  • the distillate, gas product and hydrogen are first separated by inertial separation distributor set at the inlet of the hot high pressure separator.
  • the operating pressure of the hot high pressure separator is 8. 3 MPa (G), and the pressure drop of the inertial separation distributor is
  • the vapor-liquid separated two phases are separated, and the separated liquid phase is subjected to secondary degassing by means of a centrifugal degassing method by means of a swirling or centrifugal pressure gradient field, and the pressure gradient field pressure is from the outer wall to the center.
  • the pressure difference is 1.2 MPa
  • the separated gas phase is separated from the upper portion by a cyclone separation and then discharged to a hot low pressure separator, and the separated liquid phase is discharged from the lower portion of the hot low pressure separator.
  • the operating temperature of the hot high pressure separator is 225-235'C
  • the operating temperature of the hot low pressure separator is 205-215 °C.
  • the gas-liquid two-phase separation effect is better by the built-in inlet inertial separation distributor, and some heavy hydrocarbon components that were previously difficult to separate are separated, and the efficiency of the hot high-pressure separator is improved;
  • the flash separator is injected through the built-in inlet to enhance the flash separation effect and improve the hydrogen recovery rate;
  • the hydrogen recovery rate is improved by centrifugal degassing technology before the liquid phase outlet of the hot low pressure separator.
  • FIG. 4 is a second embodiment of the present invention. Different from the first embodiment, this embodiment further parallels a similar structure of the second hot low pressure separator 3 through a heat exchanger at the gas phase outlets 2-6 of the hot low pressure separator 2 to separate the 2 gas phases in the hot low pressure. After the outlet, the low-gas is exchanged, part of the hydrocarbon is turned into a liquid phase, and the second hot-cold low-pressure separator 3 is used to further purify the hydrogen contained in the low-gas. Compared with the first embodiment, the process further purifies the hydrogen, which is more favorable for the recovery and utilization of the hydrogen.
  • the centrifugal degassing core tube in the above embodiment comprises a cavity provided with a liquid gas inlet, a gas phase outlet and a liquid phase outlet, the gas phase outlet being inserted into the cavity from the center of the upper surface of the cavity, and inserted
  • the depth is 0.1 to 3 times the maximum diameter of the cavity.
  • the insertion depth is the end of the gas phase outlet, that is, the depth from the lowest end of the gas phase outlet located in the chamber to the upper surface of the chamber.
  • FIG. 6-1 to FIG. 6-3 The inventor of the present invention found that there is significant pressure in the radial section of the cyclone at a position where the height of the column cavity is 0.5 to 3 times of the diameter of the column cavity.
  • the gradient that is, the radial position, gradually decreases from the outside to the inside.
  • the liquid pressure of the outer wall of the cyclone is high and the center pressure is low.
  • the dissolved gas of the outer wall can migrate to the center position under the partial pressure, and the overflow gas phase outlet can be set at this position.
  • the dissolved gas in the liquid under the inlet pressure is further removed.
  • the cyclone degassing technology utilizes a centrifugal field to remove the entrained liquid to widen to combine the centrifugal field with the pressure gradient field to remove the dissolved gas at a certain partial pressure of the entrained liquid and the inlet liquid.
  • FIG. 7 which includes a cone cavity 2-3-1-3 (also a column cavity) disposed at the bottom, which is disposed above the cone cavity and has the largest diameter and is in communication with the same.
  • the cylindrical cavity 2- 3-1-2, the cone cavity 2- 3- 1-3 and the column cavity 2-3-1- 2 form a closed cavity, and the bottom of the closed cavity is provided with a liquid phase outlet 2-3-1
  • the ventilator is inserted into the closed cavity, the depth of the cavity is 0.1 to 3 times the maximum diameter of the cavity, and It is disposed at the center of the cavity, and the gas outlet is an inverted bell mouth whose end section is opposite to the center position of the radial section pressure gradient field pressure, so as to utilize the pressure gradient as much as possible to collect the gas phase overflowing due to the small central pressure.
  • the gas phase outlet is specifically realized by a second injection separation pipe 2-3-1-9.
  • the injection secondary separation overflow pipe 2-3-1-9 is disposed in the column chamber 2-3- 1 - 2 on the center shaft, including a bell mouth 2-3-1-9-1, the first overflow pipe column cavity 2-3 - 1-9-2 and a reverse tapered connecting cavity 2-3 - 1- 9-3, and the second overflow pipe column cavity 2-3-1-9-4, forming a jet-shaped overflow cavity with a decreasing radius first, which can increase the gas collection area and increase the gas collection rate. At the same time increase the gas phase outlet pressure.
  • the second overflow pipe column cavity is provided with an annular gap slot 2-3-1-8 on the side of the 2-3-1-9-4 circumference, and a ring body 2 - 3-1 is provided outside the annular gap slot 2-3_1_8 -9-5 surrounds the overflow pipe to form a closed cavity, and the bottom end of the cylinder body 2-3-1-9-5 is provided with a secondary liquid outlet 2-3-1-7, in the second overflow
  • the flow tube cavity is in the range of 2-3-1-9-4, so that the gas entrained by the gas can be effectively removed by the centrifugal force of the gas, thereby realizing the effective separation of the entrained liquid in the gas, and eliminating the secondary separation due to the entrainment of the liquid by the outlet gas. The problem.
  • the lower end of the first overflow cylinder chamber 2-3-1-9-2 is also provided with a bell mouth 2-3-1-9-1 to capture the overflow gas as much as possible.
  • the bell mouth is 2-3-1-9-1 on the side of the side is provided with an overflow pipe inverted cone thick wall 2-3-1-6, the overflow pipe inverted cone thick wall 2-3-1-6 from the bell mouth 2-3-1-9-1—up to the upper surface of the column chamber 2-3-1-2 to guide the liquid gas entering from the liquid gas inlet provided at the upper or top of the chamber to enter the pressure as soon as the space is gradually increased Liquid-gas separation is performed on a region with a significant gradient.
  • the above liquid gas inlet may be in the form of an axial flow, a tangential direction, a spiral line or an involute.
  • the bottom of the cone cavity 2-3-1-2 is provided with an inner vertebral body 2-3-1-5, and the inner surface of the inner cone 2-3-1-5 is larger than the gas phase outlet and penetrates into the end of the cavity portion.
  • the bottom surface area of -1-9-1 to reduce gas carryover in the outlet liquid.
  • the inertial separation distributor in the above embodiment includes a plurality of inertial separation distribution blades 1-2-1 disposed on both sides, and covering the plurality of inertial separation distribution blades 1
  • the upper cover plate 1-2-2 above the -2-1, the lower cover plate 1-2-3 disposed under the plurality of inertial separation distribution blades 1-2-1, the inertia guide vane 1-2- 1 is composed of a straight line segment, a semicircle of the blade corner and a straight line segment, and the straight line segment is near one end of the box, and the plurality of inertial separation distribution blades 1-2-1 located on both sides are transverse to the hot high pressure separator 1.
  • the centerline of the section is symmetrically distributed.
  • the upper and lower sides of the plurality of inertial distribution blades 1-2-1 are provided with an upper cover or a lower cover.
  • the upper and lower covers are inclined from the center to the edge, and the inclination angle is 3 to 60 degrees.
  • the flash jet core tube described above can be realized by an ejector such as a venturi ejector.

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Abstract

一种提高加氢热高分流程中氢气利用率的方法及装置。加氢后馏分油、气体产物与氢气首先在高压下通过热高压分离器（1）入口（1-1）设置的惯性分离分布器（1-2）进行初步的气液分离，气相去后续系统；液相进入热低压分离器（2），在热低压分离器（2）内经喷射闪蒸分离器（2-1）初步分离释放出一部分低分气（主要为氢气），依靠重力沉降分为气相及液相；在该压力下依然溶解于热低分油的氢气及部分微小气泡通过离心脱气设备（2-3）进行分离；气相部分通过旋流分离或聚结分离将携带的液滴脱除干净后出装置，馏分油去后续设施。

Description

提高加氢装置氢气利用率的方法及装置
技术领域
本发明涉及用氢精制烃油领域， 尤其涉及一种利用惯性分离分布技术、喷射闪蒸 及离心脱气组合技术提高加氢装置氢气利用率的的方法及装置。 发明背景
随着原油资源的日益短缺和重质化、劣质化发展， 馏分油加氢工艺在清洁燃料生 产中获得了广泛应用。 另外,在目前页岩气、 天然气及煤化工中， 也广泛采用馏分油 加氢工艺， 以得到清洁的燃料。
传统烃油加氢过程反应系统需要大量的氢气保证一定的氢分压，其中小部分氢气 通过加氢化学反应消耗掉， 大部分由循环氢压缩机升压后循环使用。 常规渣油加氢、 加氢裂化、加氢处理、加氢改质、加氢精制等中高压加氢工艺反应产物的分离流程通 常有冷高分流程和热高分流程。通常全部反应产物经过空冷器后进行气液分离的流程 称为冷高分流程； 而全部反应产物在某温度下先进行一次气液分离， 闪蒸出的油气再 经换热和空冷后进行二次分离的流程， 称为热高分流程。冷高分和热高分流程已经被 广泛地应用于国内外加氢装置中。冷高分和热高分流程的选择的核心问题是如何对两 种流程进行经济性比较。 热高分流程的优点是： 降低装置能耗， 减少冷换面积； 对 于高寒地区可以减少空冷器凝冻现象的发生； 对于全循环流程， 有利于防止稠环芳烃 的积累而堵塞高压空冷器。但其缺点是：增加高温油气分离系统，并且氢气损失较大， 循环氢的浓度也略低于冷高分流程， 造成整个反应系统的压力略有增加。采用热高分 流程的前提条件就是低分气中含有的氢气必须得到有效地回收，溶解在冷低分油和热 低分油中的氢气通常认为是氢气损失的一部分。
目前热高分流程中，氢气与加氢后馏分油在热高压分离器特定温度和压力下进行 气液相分离， 该分离釆用重力沉降分离； 热高压分离器气相经循环氢压缩机升压返回 反应系统，热髙压分离器液相经减压闪蒸后在热低压分离器特定温度和压力下释放出 低分气，低分气中的氢含量一般约为 70%，通过重力沉降分离后一般将这部分低分气 作为富氢气体送至 PSA装置回收其中的氢气。一般中高压加氢装置热低压分离器压力 设计在 1. 2〜3. 0 MPa (G)， 以保证分离出的低分油靠压力进入到分馏塔中， 进入分馏 塔分离出来的氢气因含量较低不能回收通常作为燃料气使用， 氢气的利用效率较低。 因目前加氢热高分流程中热高压分离器、热低压分离器气液两相通常都采用自然的重 力沉降， 如附图 1所示，因此不可避免的部分气体（主要为氢气） 以微小气泡存在于 液相中， 随之送往后续装置， 造成了部分氢气的损失； 另外， 热低压分离器采用传统 的闪蒸-重力沉降分离方法， 因停留时间一定的操作条件下液气相接触表面较小造成
确认本 闪蒸效率低， 造成了部分氢气损失； 最后因热低压分离器压力设计在 1. 2〜3. 0 MPa (G)， 在此分压下液相中还会溶解部分氢气， 也造成了部分氢气的损失。 因此需采用 更高效的方法对该部分氢气进行回收利用， 这对企业高效、 经济的运行将带来好处。 发明内容 为了克服上述现有技术的不足，本发明提供了一种提高加氢热高分流程中氢气利 用率的方法及装置。 加氢后馏分油、气体产物与氢气首先在高压下通过热高压分离器进口设置的惯性 分离分布器进行初步的气液分离，强化气体分离效率， 气相经冷高压及后续设施后经 循环氢压缩机返回反应系统;液相第一步经喷射闪蒸技术进行初步分离释放出一部分 低分气 （主要为氢气）， 分离出的气相依靠重力沉降方法分为气相及液相； 在该压力 下依然溶解于镏分油的气体及部分微小气泡通过第二步的离心脱气方法进行分离，依 靠离心脱气设备的压力梯度（径向截面自外向内压力逐渐降低）及离心场， 溶解于馏 分油的气体由于压力梯度场分压的降低而析出，该部分析出气体及微小气泡在离心场 下得到进一步的分离；气相部分通过旋流分离或聚结分离将携带的液滴脱除干净后出 装置， 馏分油去后续设施。 该方法装置弥补了现有技术的不足， 提高了氢气的回收利 用率。
具体的技术方案为：
一种提高加氢热高分流程中氢气利用率的方法， 包括以下步骤：
步骤 1 : 热高压分离器入口设置惯性分离分布器对加氢处理后的馏分油与氢气混 合物进行初步分离， 惯性分离分布器的压降为 0. 0001~0. OlMPa; 其次通过重力沉降 进行二次分离，分离后的气相经旋流或者聚结分离去后续装置，液相去热低压分离器， 热高压分离器内操作压力为 2-30MPa， 操作温度为 200-270Ό ; 步骤 2: 进入热低压分离器的馏分油首先通过喷射闪蒸技术对馏分油中溶解的气 相进行分离， 该过程的压降不大于 0. OlMPa; 其次通过重力沉降对闪蒸分离出的气液 两相进行分离，分离出的液相采用离心脱气法依靠旋流或离心的压力梯度场对熘分油 进行二次脱气， 该压力梯度场内压力差为 0. 01~10 MPa， 分离出的气相从上部经旋流 或者聚结分离后出热低压分离器， 分离出的液相从下部出热低压分离器， 热低压分离 器的操作压力为 0. 6-5MPa, 操作温度为 170-240°C ; 一种实现前述的提高加氢热高分流程中氢气利用率的装置,包括一设置有入口、 液相出口和气相出口的热高压分离器和一设置有入口、液相出口和气相出口的热低压 分离器， 该热高压分离器的液相出口同热低压分离器的入口相连通， 该热低压分离器 入口处设置有一喷射闪蒸分离器， 该喷射闪蒸分离器包括至少一喷射闪蒸芯管； 该热 低压分离器设置于液相出口前设置有至少一离心脱气芯管，该离心脱气芯管包括一腔 体， 该腔体上设有液气进口、气相出口和液相出口， 该气相出口从该腔体上表面中心 插入该腔体内， 插入深度为该腔体最大直径的 0. 1~3倍。 进一步， 该热高压分离器的入口处设置有至少一惯性分离分布器， 该惯性分离分 布器包括设置于两侧的多个惯性分离分布叶片、上盖板和下盖板， 该惯性导流叶片包 括导流直线段、 叶片转角半圆和分布直线段组成， 导流直线段为近箱体一端； 该多个 惯性分离分布叶片可采用一层或者上下多层布置。
进一步，所述惯性分离分布器的上盖板或下盖板采用自进料中心线到边缘倾斜设 置方式， 倾斜角度为 3~60度。 进一步， 所述热高压分离器气相出口或 /和热低压分离器气相出口处设置有一气 液分离器。
进一步， 所述气液分离器为气液旋流或聚结分离器。
进一步， 所述热低压分离器包括多个喷射闪蒸芯管， 该多个喷射闪蒸芯管并联在 热低压分离器径向截面均布安装形式，通过该喷射闪蒸芯管液体流速可增大 1-20倍。 进一步， 所述喷射闪蒸分离器出口处设置对应的伞状布液器，伞状布液器表面积 为喷射闪蒸芯管出口面积的 1-30倍。
进一步， 所述热低压分离器包括多个所述离心脱气芯管， 该多个离心脱气芯管并 联且在热低压分离器径向截面均布设置。 进一步， 所述热低压分离器还包括一将热低压分离器分为两个腔室的分隔板， 该 分隔板设置高度同所述离心脱气芯管设置高度相适应，以将离心脱气芯管的进口及液 相出口分隔置于前述两个腔室内。
本发明的有益效果在于： 本发明首先采用惯性分离分布的方法强化气液分离，提 高热高压分离器的氢气分离效率； 其次采用喷射闪蒸、液体伞状均布技术提高馏分油 闪蒸脱气效率， 在重力场作用下首先对馏分油携带气及压降释放的溶解气进行分离， 其后对在该热低压分离器操作压力下溶解的气体靠闪蒸方法无法有效去除、对闪蒸分 离出的馏分油中分散的微小气泡靠重力沉降也无法有效去除利用离心脱气方法进行 二次分离， 该分压下的溶解气体依靠离心液气分离的压力梯度场（径向截面自外向内 压力逐渐降低）进行分离、 馏分油中夹带的微小气泡依靠离心场有效去除。
本发明所述方法中， 如经热低压分离器出来的馏分油还需进行闪蒸回收氢气的 话， 可直接采用离心脱气方法对馏分油携带气及溶解气进行分离， 这样可进一步有效 减少液相降压后再增压的能耗。 本发明采用的设备具有操作简单、 占地面积小、 脱气效率高等优点， 克服了目前 热高分流程氢气损耗大的问题， 可广泛应用于馏分油加氢处理过程。 附图说明 图 1-1为现有工艺流程示意图。
图 1-2为现有装置流程示意图。
图 2为本发明工艺流程示意图。 图 3为本发明第一实施例装置流程示意图。
图 4为本发明第二实施例装置流程示意图。
图 5-1为热高压分离器入口惯性分离分布器俯视图。
图 5-2为热高压分离器入口惯性分离分布器左视图。
图 6-1为离心脱气芯管结构示意图。
图 6-2为离心脱气芯管沿 A-A剖线的剖视图的径向压力示意图。 图 6-3为离心脱气芯管径向截面压力梯度分布仿真图。
图 7为离心脱气芯管结构细节图。 符号说明：
1为热高压分离器； 1-1为热高压入口； 1-2为惯性分离分布器； 1-3为热高压 气相出口； 1-4为出口气液分离器； 1-5热高压液相出口； 2为热低压分离器； 2-1 为喷射闪蒸分离器； 2-1-1为喷射闪蒸芯管； 2-2为伞状布液器； 2-3为离心脱气设 备； 2-3-1为离心脱气芯管； 2-4为分隔板； 2- 5为气液分离器； 2-6为热低压气相 出口； 2-7 为热低压入口； 2- 8为热低压液相出口； 1-1- 1为热高压入口管道； 1-2-1 为惯性分离分布叶片； 1-2-2为上盖板； 1-2- 3为下盖板； 3为第二热低压分离器。
2-3-1-1-1为 液气轴流式进口； 2- 3- 1-1-2为液气切向进口；2-3- 1-2 为 柱腔； 2- 3- 1-3 为 锥腔； 2-3-1-4为 离心脱气芯管液相出口； 2- 3-1- 5内锥体； 2-3-1-6 为 溢流管倒锥厚壁； 2-3-1-7 为 二次液出口； 2-3-1-8 为环形槽隙， 2- 3- 1-9为 喷射二次分离溢流管， 2-3-1-9-1 为 喇叭口， 2-3-1-9-2 为 第一溢流管柱腔， 2-3-1-9-3为 倒锥形连接腔， 2-3-1-9-4为 第二溢流管柱腔， 2-3-1-9-5为筒体。
具体实施方式 本发明提高加氢装置氢气回收的装置， 包括一设置有入口、液相出口和气相出口 的热高压分离器和一设置有入口、液相出口和气相出口的热低压分离器， 该热高压分 离器的液相出口同热低压分离器的入口相连通，该热低压分离器入口处设置有一喷射 闪蒸分离器， 该喷射闪蒸分离器包括至少一喷射闪蒸芯管； 该热低压分离器设置于液 相出口前设置有至少一离心脱气芯管， 该离心脱气芯管包括一腔体， 该腔体上设有液 气进口、气相出口和液相出口， 该气相出口从该腔体上表面中心插入该腔体内， 插入 深度为该腔体最大直径的 0. 1-3倍。 本发明提高加氢装置氢气回收的工艺流程如下： 加氢后馏分油、气体产物与氢气 首先采用热髙压分离器入口设置的惯性分离分布器进行初步分离，惯性分离分布器的 压降为 0. 0001~0. OlMPa; 其次通过重力沉降进行二次分离， 经热高压分离器内惯性 分离分布器及腔体沉降分离后，气相（循环氢及部分轻馏分油）去后续装置，液相（馏 分油及溶解气）进入热低压分离器； 进入热低压分离器的馏分油首先通过喷射闪蒸技 术对馏分油中溶解的气相进行分离， 该过程的压降不大于 0. OlMPa; 其次通过重力沉 降对闪蒸分离出的气液两相进行分离，分离出的液相采用离心脱气法依靠旋流或离心 的压力梯度场对馏分油进行二次脱气， 该压力梯度场内压力差为 0. 01~10 MPa, 经喷 射闪蒸器闪蒸分离后， 气相（低分气， 主要为氢气）去 PSA回收， 液相及溶解气以及 携带的微小气泡去离心脱气器进行二次脱气分离，之后液体（馏分油）从下部出设备， 分离出的气相从上部气相出口去 PSA回收。
通过该发明的实施， 可显著克服目前加氢热高分流程中热高压分离器、热低压分 离器气液两相自然的重力沉降分离效率低的问题， 解决部分气体（主要为氢气）以微 小气泡存在于液相中， 随之送往后续装置， 造成的部分氢气的损失； 另外， 克服了目 前热低压分离器采用传统的闪蒸-重力沉降分离方法， 因停留时间一定的操作条件下 液气相接触表面较小造成闪蒸效率低，造成了部分氢气损失的问题； 最后克服了热低 压分离器压力设计在 1. 2〜3. 0 MPa (G) 时液相中溶解部分氢气， 造成部分氢气损失 的问题。 该发明的实施提高了氢气的回收利用率， 对企业生产装置的高效、 经济运行 将带来好处。
实施例 1：
某石化加氢装置采用热高分流程， 热高压分离器进料参数如下:
Figure imgf000007_0001
水相 kg/h 操作温度 -最高 /正常 /最低 /210/ 。C
操作压力 -最高 /正常 /最低 8. 4/8. 3/ MPa(g) 真空或负压 -最高 /最低 全真空 MPa(abs) 介质密度 -操作温度下
气相 18. 3969 kg/m3 油相 733. 4492 kg/m3 注： 操作初期： 气相中 H2浓度为 73. 8946% (v) , H2S浓度为 1. 8413% (v)， 液相中 H2S浓度为 0. 177% (wt) ; 操作末期： 气相中 H2浓度为 73. 7534% (v)， H2S浓度为 1. 3705% (V) , 液相中 H2S浓度为 0. 132% (wt)。
请参阅图 1-广图 1-2， 现有加氢热高压分离流程通过以下步骤实现， 加氢后馏分 油、 气体产物与氢气首先进入热高压分离器 1在一定的温度和压力下进行气液分离， 分离采用重力沉降方式， 分离出的气相去后续装置， 液相进入热低压分离器 2进行闪 蒸， 闪蒸出的气液两相再通过重力沉降方式分离， 分离出的气相（低分气）去 PSA进 行氢气回收， 液相去后续脱硫及分馏装置。在当前分离过程中， 气液两相通常都采用 自然的重力沉降，因此不可避免的部分气体（主要为氢气）以微小气泡存在于液相中， 随之送往后续装置， 造成了部分氢气的损失； 另外， 热低压分离器采用传统的闪蒸- 重力沉降分离方法，因停留时间一定的操作条件下液气相接触表面较小造成闪蒸效率 低， 造成了部分氢气损失； 最后因热低压分离器压力设计在 1. 2〜3. 0 MPa (G)， 在此 分压下液相中还会溶解部分氢气， 也造成了部分氢气的损失。 因此需采用更高效的方 法对该部分氢气进行回收利用， 这对企业高效、 经济的运行将带来好处。
相较现有的工艺流程及装置， 本实施例进一步采用了前述发明的方法与装置。请 参阅图 1〜图 2， 为本发明第一实施例装置及其流程示意图， 该装置包括一设置有入 口 1-1、 液相 1-5出口和气相出口 1-3的热高压分离器 1和一设置有入口 2-7、 液相 出口 2-8和气相出口 2-6的热低压分离器 2， 该热高压分离器 1的液相出口 1-5同热 低压分离器的入口 2-7相连通，该热低压分离器入口 2-7处设置有一喷射闪蒸分离器 2-1，该喷射闪蒸分离器 2-1包括多个喷射闪蒸芯管 2-1-1，该多个喷射闪蒸芯管 2-1-1 并联并在热低压分离器 2径向截面均布安装， 通过该喷射闪蒸芯管液体流速可增大 1 - 20倍。， 每个喷射闪蒸芯管 2-1-1喷射口处均设有对应的伞状布液器 2-2， 伞状布 液器 2-2表面积为喷射闪蒸芯管出口面积的 1-30倍。 该热低压分离器 2于液相出口 前设置有多个离心脱气芯管 2-3， 该多个离心脱气芯管 2-3并联且在热低压分离器径 向截面均布设置。 热高压分离器 1气相出口处设置有一气液分离器 1-4， 热低压分离 器 2气相出口处设置有一气液分离器 2-5，该气液分离器 1-4、 2-5为气液旋流或聚结 分离器。 热低压分离器 2还包括一将热低压分离器 2分为两个腔室的分隔板 2-4， 该 分隔板 2-4设置高度同所述离心脱气芯管 2-3设置高度相适应，以将离心脱气芯管 2-3 的进口及液相出口分隔置于前述两个腔室内。
加氢后馏分油、气体产物与氢气首先采用热高压分离器入口设置的惯性分离分布 器进行初步分离，热高压分离器的操作压力为 8. 3MPa (G)，惯性分离分布器的压降为
0、 0004MPa; 其次通过重力沉降进行二次分离， 分离后的气相经旋流分离去后续装置， 该过程的压降为 0. 005MPa,液相去热低压分离器；进入热低压分离器的馏分油首先通 过喷射闪蒸技术对馏分油中溶解的气相进行闪蒸分离，该过程的压降为 O. OOlMPa,热 低压分离器内操作压力为 2. 9MPa (G);其次通过重力沉降对闪蒸分离出的气液两相进 行分离，分离出的液相采用离心脱气法依靠旋流或离心的压力梯度场对馏分油进行二 次脱气， 该压力梯度场内压力自外壁到中心的压力差为 1. 2 MPa, 分离出的气相从上 部经旋流分离后出热低压分离器， 分离出的液相从下部出热低压分离器。其中， 热高 压分离器的操作温度为 225-235'C， 热低压分离器操作温度为 205-215°C。 实施效果： 与原工艺流程（即热高压分离器中气液釆用重力沉降进行分离， 热低 压分离器中首先通过闪蒸将热高压出来的液相中所含气相进行分离，其次通过重力沉 降进行气液两相分离）相比， 存在以下有益效果：
1、 在热高压分离器中通过内置入口惯性分离分布器， 气液两相分离效果更好， 部分 以前难以分离的重烃组分得到了分离， 提高了热高压分离器的效率；
2、 在热低压分离器中通过内置入口喷射闪蒸分离器， 强化了闪蒸分离效果， 提高了 氢气的回收率；
3、 在热低压分离器液相出口前通过离心脱气技术提高了氢气回收率。
实施例 2:
请参阅图 4，为本发明的第二实施例。与第一实施例不同的是本实施例在热低压分 离器 2的气相出口 2-6处通过一换热器进一步串联了一同样结构第二热低压分离器 3， 以在热低压分离 2气相出口之后， 对低分气进行了换热， 部分烃变成液相， 再通第二 热低压分离器 3对低分气中所含氢气进行进一步提纯。与实施例 1相比， 本流程进一 步对氢气进行了提纯， 更有利于氢气的回收利用。
上述实施例中的离心脱气芯管， 包括设有一腔体， 该腔体上设有液气进口、 气 相出口和液相出口， 该气相出口从该腔体上表面中心插入该腔体内， 插入深度为该腔 体最大直径的 0. 1~3倍。该插入深度为气相出口末端、即位于腔体内的气相出口最低 端至腔体上表面的深度。 其原理请参阅图 6-1〜图 6-3， 本专利发明者通过实验研究 发现，在柱腔高度为柱腔直径的 0. 5~3倍位置，旋流器内径向截面存在显著的压力梯 度， 即径向位置从外到内压力逐渐减小。 依据亨利定律， 在该截面高度附近， 旋流器 外边壁液体压力高、 中心压力低， 外边壁在该分压下溶解气体可迁移到中心位置， 将 溢流气相出口设在该位置可将一定进口压力下液体中溶解的气体进一步进行脱除，将 目前旋流脱气技术利用离心场脱除夹带液体拓宽到利用离心场与压力梯度场结合，脱 除夹带液体与进口液体一定分压下的溶解气体。
具体实现可以如以下示例， 请参阅图 7， 包括一设于底部的锥腔 2-3- 1-3 (也可 为柱腔）， 设于锥腔之上、最大直径相同并与之连通的柱腔 2- 3-1-2, 该锥腔 2- 3- 1-3 和柱腔 2-3-1- 2形成一封闭腔体， 封闭腔体底部设有一液相出口 2-3-1-4， 封闭腔体 上部设有液气进口， 封闭腔体上部设有一气相出口， 该气相出口从上表面插入封闭腔 体， 插入的深度为腔体最大直径的 0. 1~3倍，并设置于腔体中心， 气相出口为一倒喇 叭口， 其末端截面正对径向截面压力梯度场压力最小的中心位置， 以便尽可能的利用 压力梯度收集因中心压力较小而溢出的气相。该气相出口具体通过一喷射二次分离溢 流管 2-3-1- 9实现， 如图所示， 该喷射二次分离溢流管 2-3-1-9设置于柱腔 2-3-1 - 2 中心轴上， 包括一喇叭口 2-3-1-9-1， 第一溢流管柱腔 2-3- 1-9-2及一倒锥形连接腔 2-3- 1-9-3，和第二溢流管柱腔 2-3-1-9-4，形成半径先减小后增大的喷射形溢流腔体， 可在加大气体收集面积， 提高气体收集率的同时提高气相出口压力。该第二溢流管柱 腔 2-3-1-9-4 周侧开设有环隙开槽 2-3-1-8， 环隙开槽 2-3_1_8 外设有一筒体 2 - 3-1-9-5包围所述溢流管以形成一封闭的腔体， 该筒体 2-3-1-9-5底端开设有二次 液出口 2-3-1-7， 在第二溢流管柱腔 2-3-1-9- 4内， 以便利用气体旋转离心力将气体 夹带的液体进行有效脱除， 实现气体中夹带液体的有效分离， 可消除因出口气体夹带 液体而二次分离的问题。 第一溢流管柱腔 2-3-1-9-2 的下端还设有一喇叭口 2-3-1-9-1， 以尽可能大的捕获溢出气体。 该喇叭口 2-3-1-9-1周侧设有一溢流管倒 锥厚壁 2-3-1-6， 该溢流管倒锥厚壁 2-3-1-6 从该喇叭口 2-3-1-9-1 —直至柱腔 2-3-1-2的上表面， 以便引导从设置于腔体上部或顶部的液气进口进入的液气由于空 间逐渐增大尽快进入压力梯度显著的区域进行液气分离。 上述液气进口可采用轴流 式、 切向、 螺旋线或渐开线形式。 该锥腔 2-3-1-2底部设有一内椎体 2-3-1-5， 该内 锥体 2-3-1-5底面面积大于气相出口深入腔体部分末端喇叭口 2-3-1-9-1 的底面面 积， 以降低出口液体中气体携带。
上述实施例中的惯性分离分布器， 请参阅图 5-1〜图 5-2， 包括设置于两侧的多 个惯性分离分布叶片 1-2-1、 及覆盖于多个惯性分离分布叶片 1-2-1 之上的上盖板 1-2-2、 设置于多个惯性分离分布叶片 1-2-1之下的下盖板 1-2-3， 该惯性导流叶片 1-2-1由导流直线段、 叶片转角半圆和分布直线段组成， 导流直线段为近箱体一端， 设于两侧的多个惯性分离分布叶片 1-2-1对于热高压分离器 1的横截面中心线对称分 布。多个惯性分布叶片 1-2-1的上下设置有上盖板或下盖板， 该上下盖板采用自中心 到边缘倾斜设置方式， 倾斜角度为 3~60度。
上述闪蒸喷射芯管可通过喷射器实现， 如文丘里喷射器。
综上所述仅为发明的较佳实施例而已， 并非用来限定本发明的实施范围。 即凡依 本发明申请专利范围的内容所作的等效变化与修饰， 都应为本发明的技术范畴。

Claims

权利要求
1. 一种提高加氢热高分流程中氢气利用率的方法， 其特征在于， 包括以下步骤： 步骤 1 : 馏分油与氢气混合物进行热高压分离， 包括以下步骤：
步骤 1. 1 :馏分油与氢气混合物通过惯性分离分布实现初步气液分离及分离后的气 液混合物在热高压分离器内径向截面均布，该惯性分离的压降为 0. 0001-0. OlMPa; 步骤 1. 2 : 惯性分离分布后的气液混合物通过重力沉降进行二次气液分离； 步骤 2: 经热高压分离后的液相进行热低压分离分离， 包括以下步骤：
步骤 2. 1 : 通过喷射闪蒸对液相中溶解的气相进行分离， 该过程的压降不大于 0. OlMPa;
步骤 2. 2:喷射闪蒸后的气液混合物通过重力沉降对闪蒸分离出的气液两相进行分 离， 分离出的液相采用离心脱气法依靠旋流或离心的压力梯度场对液相进行二次 脱气， 该压力梯度场内压力差为 0. 01~10 MPa。
2. 一种实现如权利要求 1方法所述的提高加氢热高分流程中氢气利用率的装置，包括 一设置有入口、 液相出口和气相出口的热高压分离器和一设置有入口、 液相出口 和气相出口的热低压分离器， 该热高压分离器的液相出口同热低压分离器的入口 相连通， 其特征在于，
该热低压分离器入口处设置有一喷射闪蒸分离器， 该喷射闪蒸分离器包括至少一 喷射闪蒸芯管；
该热低压分离器于液相出口前设置有至少一离心脱气芯管， 该离心脱气芯管包括 一腔体， 该腔体上设有 ua液气进口、 气相出口和液相出口， 该气相出口从该腔 体上表面中心插入该腔体内， 插入深度为该腔体最大直径的 0. 1-3倍。
3. 如权利要求 2所述的提高加氢热高分流程中氢气利用率的装置，其特征在于，该热 高压分离器可以为立式或者卧式， 在入口处设置有至少一惯性分离分布器， 该惯 性分离分布器包括设置于两侧的多个惯性分离分布叶片、 上盖板和下盖板， 该惯 性导流叶片包括导流直线段、 叶片转角半圆和分布直线段组成， 导流直线段为近 箱体一端；
4. 如权利要求 3所述的提高加氢热高分流程中氢气利用率的装置，其特征在于，所述 惯性分离分布器的上盖板或下盖板采用自进料中心线到边缘倾斜设置方式， 倾斜 角度为 3~60度。
5. 如权利要求 2所述的提高加氢热高分流程中氢气利用率的装置，其特征在于，所述 热高压分离器气相出口或 /和热低压分离器气相出口处设置有一气液分离器。
6. 如权利要求 5所述的提高加氢热高分流程中氢气利用率的装置,其特征在于，所述 气液分离器为气液旋流或聚结分离器。
7. 如权利要求 2所述的提高加氢热高分流程中氢气利用率的装置， 其特征在于， 所 述热低压分离器包括多个喷射闪蒸芯管， 该多个喷射闪蒸芯管并联， 且在热低压 分离器径向截面均布设置， 热低压分离器可以为卧式或者立式布置。
8. 如权利要求 2所述的提高加氢热高分流程中氢气利用率的装置， 其特征在于， 所 述喷射闪蒸分离器出口处设置对应的伞状布液器， 伞状布液器表面积为喷射闪蒸 芯管出口面积的 1-30倍。
9. 如权利要求 2所述的提高加氢热高分流程中氢气利用率的装置， 其特征在于， 所 述热低压分离器包括多个所述离心脱气芯管， 该多个离心脱气芯管并联且在热低 压分离器径向截面均布设置。
10. 如权利要求 1所述的提高加氢热高分流程中氢气利用率的装置， 其特征在于， 所述热低压分离器还包括一将热低压分离器分为两个腔室的分隔板， 该分隔板设 置高度同所述离心脱气芯管设置高度相适应， 以将离心脱气芯管的进口及液相出 口分隔置于前述两个腔室内。
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