EP0420651A1 - Procédé d'hydrotraitement en suspension en plusieurs étapes - Google Patents

Procédé d'hydrotraitement en suspension en plusieurs étapes Download PDF

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Publication number
EP0420651A1
EP0420651A1 EP90310609A EP90310609A EP0420651A1 EP 0420651 A1 EP0420651 A1 EP 0420651A1 EP 90310609 A EP90310609 A EP 90310609A EP 90310609 A EP90310609 A EP 90310609A EP 0420651 A1 EP0420651 A1 EP 0420651A1
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EP
European Patent Office
Prior art keywords
hydrotreating
catalyst
feed
temperature
hydrogen
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Application number
EP90310609A
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German (de)
English (en)
Inventor
William Edward Winter, Jr.
Willard Hall Sawyer
Russell Robert Chianelli
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ExxonMobil Technology and Engineering Co
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Exxon Research and Engineering Co
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Publication of EP0420651A1 publication Critical patent/EP0420651A1/fr
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    • 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
    • C10G65/00—Treatment of hydrocarbon oils by two or more hydrotreatment processes only
    • C10G65/02—Treatment of hydrocarbon oils by two or more hydrotreatment processes only plural serial stages only
    • C10G65/04—Treatment of hydrocarbon oils by two or more hydrotreatment processes only plural serial stages only including only refining steps
    • C10G65/08—Treatment of hydrocarbon oils by two or more hydrotreatment processes only plural serial stages only including only refining steps at least one step being a hydrogenation of the aromatic hydrocarbons

Definitions

  • This invention relates to a process employing a catalyst slurry for the hydrotreating of a heavy fuel oil. More particularly, the process comprises a high temperature hydrotreating stage followed by one or more lower temperature stages.
  • the petroleum industry employs hydrotreating to upgrade the quality of gas oils in order to make them suitable as a feedstock to a fluid catalytic cracker (FCC).
  • Hydrotreating accomplishes the hydro­genation of multi-ring aromatic compounds contained in gas oils to one-ring aromatics or completely saturated naphthenes. This is necessary to assure low coke and high gasoline yields in the cat cracker.
  • Multi-ring aromatics cannot be cracked effectively to mogas (motor gasoline) and heating oil products, whereas partially hydrogenated aromatics or naphthenes can be cracked to premium products in the naphtha and heating oil boiling range.
  • Hydrotreating is further capable of removing sulfur and nitrogen which is detrimental to the crack­ing process.
  • a slurry hydrotreating process employing temperature staging provides a means to circumvent both the kinetic and equilibrium limits conventionally encountered in either fixed bed or slurry hydrotreating processes.
  • Patent No. 4,557,821 to Lopez et al discloses hydrotreating a heavy oil employing a circulating slurry catalyst.
  • Other patents disclosing slurry hydrotreating include U.S. Patents Nos. 3,297,563; 2,912,375; and 2,700,015.
  • the present invention teaches a method of maximizing hydrogenation rates while avoiding equili­brium limits in a slurry hydrotreating process, wherein a hydrotreating catalyst of small particle size is contacted with petroleum or synfuel feedstocks for hydrogenation of aromatics and removal of organic nitrogen.
  • the slurry hydrotreating process employs a high temperature stage followed by one or more low temperature stages.
  • invention which comprises:
  • a relatively high temperature stage is followed by one or more low temperature stages.
  • a two stage process might process fresh feed in a 760°F stage and process the product from the first stage in a 720°F stage.
  • several stages can be operated at successively lower temperatures, such as a 780°F stage followed by a 740°F stage followed by a 700°F stage.
  • Such an arrangement provides, in the first stage, fast reaction rates and, in the final stage or stages, lower equilibrium multi-ring aromatics levels (hence greater kinetic driving forces).
  • the slurry hydrotreating process of the present invention can be used to treat various feeds from fossil fuels such as heavy catalytic cracking cycle oils (HCCO), coker gas oils, and vacuum gas oils (VGO), which contain high concentrations of aromatics.
  • HCCO heavy catalytic cracking cycle oils
  • VGO vacuum gas oils
  • Similar feeds derived from petroleum, coal, bitumen, tar sands, or shale oil are also suitable.
  • Suitable feeds for processing according to the present invention include those gas oil fractions which are distilled in the range of 500 to 1200°F, preferably in the 650 to 1100°F range. Above 1200°F it is difficult or impossible to strip all of the feed off the catalyst with hydrogen and the catalyst tends to coke up. Also, the presence of concarbon and asphaltenes gum up the catalyst.
  • the feed should not be such that more than 10% boils above 1050°F.
  • the nitrogen content is normally greater than 1500 ppm.
  • the 2+ ring aromatics represent 50% or more and the 3+ ring aromatics content of the feed should generally should represent 25% or more by weight.
  • Suitable catalysts for use in the present process are well known in the art and include, but are not limited to, molybdenum (Mo) sulfides, mixtures of transition metal sulfides such as Ni, Mo, Co, Fe, W, Mn, and the like.
  • Mo molybdenum
  • Typical catalysts include NiMo, CoMo, or CoNiMo combinations.
  • sulfides of Group VII metals are suitable.
  • catalyst materials can be unsupported or supported on inorganic oxides such as alumina, silica, titania, silica alumina, silica magnesia and mixtures thereof.
  • Zeolites such as USY or acid micro supports such as aluminated CAB-O-SIL can be suitably composited with these supports.
  • Catalysts formed in-situ from soluble precursors such as Ni and Mo naphthenate or salts of phosphomolybdic acids are suitable.
  • the catalyst material may range in diameter from 1 ⁇ to 1/8 inch.
  • the cata­lyst particles are 1 to 400 ⁇ in diameter so that intra particle diffusion limitations are minimized or elimi­nated during hydrotreating.
  • transition metals such as Mo are suitably present at a weight percent of 5 to 30%, preferably 10 to 20%.
  • Promoter metals such as Ni and/or Co are typically present in the amount of 1 to 15%.
  • the surface area is suitably about 80 to 400 m2/g, preferably 150 to 300 m2/g.
  • the alumina support is formed by precipitating alumina in hydrous form from a mixture of acidic reagents in an alkaline aqueous aluminate solution. A slurry is formed upon precipitation of the hydrous alumina. This slurry is concentrated and generally spray dried to provide a catalyst support or carrier. The carrier is then impregnated with cataly­tic metals and subsequently calcined.
  • suitable reagents and conditions for preparing the support are disclosed in U.S. patents Nos. 3,770,617 and 3,531,398, herein incorporated by reference.
  • the well known oil drop method comprises forming an alumina hydrosol by any of the teachings taught in the prior art, for example by reacting aluminum with hydrochloric acid, combining the hydrosol with a suitable gelling agent and dropping the resultant mixture into an oil bath until hydrogel spheres are formed. The spheres are then continuously withdrawn from the oil bath, washed, dried, and calcined.
  • This treatment converts the alumina hydrogel to corresponding crystalline gamma alumina particles. They are then impregnated with catalytic metals as with spray dried particles. See for example, U.S. Patents Nos. 3,745,112 and 2,620,314.
  • fresh or reactivated catalyst can be conti­nually added while aged or deactivated catalyst can be purged or regenerated.
  • the reactivated catalyst is preferably continuously recycled to the reactor. Consequently, a slurry hydrotreating process can be operated at more severe conditions than a fixed bed hydrotreater, which typically operates for 1 or 2 years before it becomes necessary to shut it down in order to replace the catalyst.
  • a feed stream 1 by way of example consisting of a gas oil feed, is introduced into a first slurry hydrotreating reactor 2 operated at a relatively higher temperature compared to a second slurry hydrotreating reactor 3.
  • the feedstream 1 Before being passed to the hydrotreater reactor 2, the feedstream 1 is typi­cally mixed with a hydrogen containing gas stream 4 and heated to reaction temperature in a furnace or pre-­heater 5.
  • a make-up hydrogen stream 6 may be intro­duced into the recycle hydrogen supply stream 4 to the hydrotreating reactor 2.
  • the hydrotreating reactor 2 contains typically 10 to 70 percent catalyst, pre­ferably about 40 to 60 percent solids by weight.
  • the feed may enter through the bottom of the reactor and bubble up through an ebulating or fluidized bed.
  • Recycle of the reactor effluent via a pump (not shown) is optional to recycle a portion of the feed for reactor mixing.
  • the effluent stream 8 from the first hydrotreating reactor 2 is suitably lowered in tempera­ture by either introducing a quench feed stream 7 and/or passing the effluent through a cooler 16.
  • further hydrogen gas is suitably introduced via stream 18 into the first hydrotreating reactor effluent stream 8 before the latter is passed into the second hydrotreating reactor 3.
  • the effluent from this second reactor is suitably passed via stream 9 through a cooler 10, and into a gas-liquid separator or dis­engaging means 11 to take off gases, principally hydrogen, before yielding a liquid product stream 12.
  • liquid products are given a light caustic wash to assure complete removal of H2S.
  • Small quantities of H2S if left in the product, will oxidize to free sulfur upon exposure to the air, and will cause the product to exceed pollution or corrosion specifi­cations.
  • the hydrotreating reactors 2 and 3 may optionally have filters at entrance and/or exit orifices to keep the catalyst particles inside the reactors.
  • the reactors may alternatively have a flare (increasing diameter) configuration such that when the reactor is kept at minimum fluidization velocity, the catalyst particles are prevented from escaping through an upper exit orifice.
  • the hydrotreating reac­tors are arranged in descending temperature such that the last reactor is between 650 and to 750°F where equilibrium is favorable for hydrogenation of aromatics to one ring aromatics.
  • the first stage is at a more elevated temperature, for example between 700 to 800°F where more rapid hydrodenitrogenation (HDN) can occur.
  • HDN hydrodenitrogenation
  • the gas-liquid separator or disengaging means 11 separates the liquid product from hydrogen gas along with ammonia and hydrogen sulfide by-products of the hydrotreating reactions and recycles them in gas stream 13 via compressor 14 back for reuse in the recycle hydrogen supply stream 4.
  • An off gas stream 15 may be removed from the gas stream 13.
  • the gas stream 13 is usually passed through a scrubber (not shown) to remove hydro­gen sulfide and ammonia because of their inhibiting effects on the kinetics of hydrotreating and also to reduce corrosion in the recycle circuit.
  • the catalyst used in the hydrotreating reactors 2 and 3 is preferably reactivated on a con­tinuous basis as described in copending application S.N. 414,166, herein incorporated by reference.
  • Spent catalyst may be removed from the reactors 2 and 3 via streams 19 and 20, respectively.
  • Fresh make-up cata­lyst may be introduced via streams 17 and/or 21 into the feed stream 1.
  • the operating conditions in the hydrotreating reactors depend to some extent on the particular feed being treated.
  • the first hydrotreating reactor is suitably at a temperature of between 700 and 800°F, preferably between 750 and 780°F and at a pressure of 800 to 4000 psig, preferably 1500 to 2500 psig.
  • the hydrogen treat gas rate is 1500 to 10,000 SCF/B, preferably 2500 to 5000 SCF/B.
  • the space velocity (WHSV) or holding time is suitably 0.2 to 5, preferably 0.5 to 2.
  • the second (low temperature) hydrotreating reactor operates at a temperature between about 650 and 750°F, preferably between 675 and 725°F and a pressure of 800 to 4000 psig, preferably 1500 to 2500 psig.
  • the hydrogen treat gas ratio is 1500 to 10,000 SCF/B, preferably 2000 to 5000 SCF/B.
  • the space velocity (WHSV) is 0.2 to 5, preferably 0.5 to 2.
  • the autoclave was heated to 690°F under 1200 psig hydrogen pressure.
  • the autoclave was operated in a gas flow thru mode so that hydrogen treat gas was added continuously while gaseous products were taken off. This hydrogen was added over the course of the run and the initial hydrogen charge plus make-up hydrogen was equivalent to 3500 SCF/B of liquid charged to the autoclave.
  • the autoclave was quenched or cooled quickly to stop reactions.
  • the autoclave reactor was depressured and the catalyst was filtered from the liquid products. These products were then analyzed to determine the extent of HDS, HDN, and aromatics hydrogenation. The results are shown in Table III.
  • Table III 1200 Psig, 3l.5 wt% Catalyst on Feed, 2 Hours at Temperature, 3500 SCF/B Hydrogen Slurry Hydrotreating Temperature, °F 690 720 730 750 780 Slurry Product Quality Wt% Sulfur .215 .065 .047 .019 .001 Wt% Nitrogen .122 .088 .086 .051 .028 Wt% Sats + 1R AR 64 63 63 64 61 Wt% 3+ R AR & Polars 21 18 22 22 25 Wt% Polar AR 2.2 1.2 1.6 1.1 0.7 MAT Conversion 58.9 63.3 61.2 60.5 57.2 MAT Coke 2.87 3.12 3.00 2.95 2.67
  • Table IV 1200 Psig, 3l.5 wt% Catalyst on Feed, 3500 SCF/B Hydrogen Slurry Hydrotreating Temperature, °F 760/720 750/690 730 Time on Temperature, Hours 1/1 1/1 4 Slurry Product Quality Wt% Sulfur .029 .065 .047 Wt% Nitrogen .054 .088 .086 Wt% Sats + 1R AR 69 63 63 Wt% 3+ R AR & Polars 16 18 22 Wt% Polar AR 0.6 1.2 1.6 MAT Conversion 63.5 59.9 64.1 MAT Coke 2.68 2.53 2.60
  • the temperature staging experiments provide both the high HDS, HDN and polar aromatics removal of the higher temperature experiments and the high heavy aromatics removal/saturates and 1 ring aromatics production of the lower temperature experiments.
  • FIG. 2 it can be seen the temperature staging experiments provided lower MAT coke yields at any given MAT conversion. The lowest MAT coke yields were observed for the product from the 750/690°F temperature staging experiment. The 760/720°F temperature staging experiment showed lower heavy aromatics levels and higher saturates plus 1 ring aromatics levels than any two hour, single temperature experiment. In order to match the results of the two hour temperature staging experiment, a single tempera­ture, say 730°F, would require four hours.
  • Table V 1200 Psig, 3l.5 wt% Catalyst on Feed, 3500 SCF/B Hydrogen Slurry Hydrotreating Temperature, °F 760/720 800/720 720 760 Time on Temperature, Hours 1/1 1/1 2 2 Slurry Product Quality Wt% Sulfur .062 .036 .126 .051 Wt% Nitrogen .144 .092 .186 .092 Wt% Sats + 1R AR 65 64 61 61 Wt% 3+ R AR & Polars 20 20 23 24 Wt% Polar AR 1.8 1.4 2.7 1.5 Comparing the results of the temperature staging experiments with the experiments run at a single temperature for 2 hours, the temperature staging experiments with recycled catalyst provided both lower heavy aromatics levels and higher saturates plus 1 ring aromatics levels than any two hour, single temperature experiment. HDS, HDN and polar aromatics removal in the temperature staging experiments were as good or better than at single temperature experiments at the same average temperature.
  • USSN 414,166 referred to herein corresponds with European patent application No. filed on or about 28 September 1990 and entitled "Slurry Hydro­treating Process", and which describes and claims a process for hydrotreating a heavy fossil fuel to hydrogenate heavy aromatics and remove sulfur, the process comprising: reacting the heavy fossil fuel in a hydro­treating zone with hydrogen in the presence of a non-noble metal containing hydrotreating catalyst; separating the catalyst from the product of the hydrotreating zone; reactivating the catalyst in a reactivating zone, separate from the hydrotreating zone, by hydrogen stripping; and recycling the reactivated catalyst to the hydrotreating zone.
  • ⁇ HPLC denotes High Performance Liquid Chromatography.
  • ⁇ GC denotes Gas Chromatography.
  • Mogas is an abbreviation for motor gasoline.
  • ⁇ SCF standardized cubic foot
  • ⁇ B barrel
  • ⁇ Mesh sizes are Tyler series.

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  • Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
  • Catalysts (AREA)
EP90310609A 1989-09-28 1990-09-27 Procédé d'hydrotraitement en suspension en plusieurs étapes Withdrawn EP0420651A1 (fr)

Applications Claiming Priority (2)

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US414175 1982-09-02
US41417589A 1989-09-28 1989-09-28

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JP (1) JPH03131686A (fr)
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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1120454A2 (fr) * 2000-01-25 2001-08-01 Haldor Topsoe A/S Procédé pour la réduction du teneur en composés soufrés et en hydrocarbures poly-aromatiques dans les charges hydrocarbonées
EP1925654A1 (fr) * 2006-11-22 2008-05-28 Haldor Topsoe A/S Procédé d'hydrotraitement catalytique de produits hydrocarbonés contenant de la silicone
US11427782B2 (en) 2018-07-20 2022-08-30 Neste Oyj Purification of recycled and renewable organic material
US11499104B2 (en) 2018-07-20 2022-11-15 Neste Oyj Purification of recycled and renewable organic material
US11624030B2 (en) 2018-07-20 2023-04-11 Neste Oyj Production of hydrocarbons from recycled or renewable organic material
US11655422B2 (en) 2018-07-20 2023-05-23 Neste Oyj Purification of recycled and renewable organic material
US11981869B2 (en) 2018-07-20 2024-05-14 Neste Oyj Purification of recycled and renewable organic material

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE645484A (fr) * 1963-03-22 1964-09-21
US4585545A (en) * 1984-12-07 1986-04-29 Ashland Oil, Inc. Process for the production of aromatic fuel
EP0277718A2 (fr) * 1987-02-02 1988-08-10 Union Oil Company Of California Saturation catalytique d'aromates dans des hydrocarbures

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE645484A (fr) * 1963-03-22 1964-09-21
US4585545A (en) * 1984-12-07 1986-04-29 Ashland Oil, Inc. Process for the production of aromatic fuel
EP0277718A2 (fr) * 1987-02-02 1988-08-10 Union Oil Company Of California Saturation catalytique d'aromates dans des hydrocarbures

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1120454A2 (fr) * 2000-01-25 2001-08-01 Haldor Topsoe A/S Procédé pour la réduction du teneur en composés soufrés et en hydrocarbures poly-aromatiques dans les charges hydrocarbonées
EP1120453A2 (fr) * 2000-01-25 2001-08-01 Haldor Topsoe A/S Procédé pour la reduction du teneur en composés soufrées et en hydrocarbures poly-aromatiques dans des combustibles de distillat
EP1120454A3 (fr) * 2000-01-25 2002-01-30 Haldor Topsoe A/S Procédé pour la réduction du teneur en composés soufrés et en hydrocarbures poly-aromatiques dans les charges hydrocarbonées
EP1120453A3 (fr) * 2000-01-25 2002-01-30 Haldor Topsoe A/S Procédé pour la reduction du teneur en composés soufrées et en hydrocarbures poly-aromatiques dans des combustibles de distillat
EP1925654A1 (fr) * 2006-11-22 2008-05-28 Haldor Topsoe A/S Procédé d'hydrotraitement catalytique de produits hydrocarbonés contenant de la silicone
RU2459858C2 (ru) * 2006-11-22 2012-08-27 Хальдор Топсеэ А/С Способ каталитической гидроочистки углеводородного сырья, содержащего кремний
US11427782B2 (en) 2018-07-20 2022-08-30 Neste Oyj Purification of recycled and renewable organic material
EP3824053B1 (fr) * 2018-07-20 2022-08-31 Neste Oyj Purification de matière organique recyclée et renouvelable
US11499104B2 (en) 2018-07-20 2022-11-15 Neste Oyj Purification of recycled and renewable organic material
US11624030B2 (en) 2018-07-20 2023-04-11 Neste Oyj Production of hydrocarbons from recycled or renewable organic material
US11655422B2 (en) 2018-07-20 2023-05-23 Neste Oyj Purification of recycled and renewable organic material
US11981869B2 (en) 2018-07-20 2024-05-14 Neste Oyj Purification of recycled and renewable organic material

Also Published As

Publication number Publication date
JPH03131686A (ja) 1991-06-05
CA2025466A1 (fr) 1991-03-29

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