Classifications

• • 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
  • C10G49/00—Treatment of hydrocarbon oils, in the presence of hydrogen or hydrogen-generating compounds, not provided for in a single one of groups C10G45/02, C10G45/32, C10G45/44, C10G45/58 or C10G47/00
  • C10G49/007—Treatment of hydrocarbon oils, in the presence of hydrogen or hydrogen-generating compounds, not provided for in a single one of groups C10G45/02, C10G45/32, C10G45/44, C10G45/58 or C10G47/00 in the presence of hydrogen from a special source or of a special composition or having been purified by a special 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
  • C10G67/00—Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one process for refining in the absence of hydrogen only
  • C10G67/02—Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one process for refining in the absence of hydrogen only plural serial stages only
  • C10G67/06—Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one process for refining in the absence of hydrogen only plural serial stages only including a sorption process as the refining step in the absence of hydrogen
• • 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
  • C10G69/00—Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one other conversion process
  • C10G69/02—Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one other conversion process plural serial stages only
• • 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
  • C10G2300/00—Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
  • C10G2300/20—Characteristics of the feedstock or the products
  • C10G2300/201—Impurities
  • C10G2300/202—Heteroatoms content, i.e. S, N, O, P
• • 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
  • C10G2300/00—Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
  • C10G2300/20—Characteristics of the feedstock or the products
  • C10G2300/201—Impurities
  • C10G2300/207—Acid gases, e.g. H2S, COS, SO2, HCN
• • 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
  • C10G2300/00—Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
  • C10G2300/80—Additives
  • C10G2300/805—Water
  • C10G2300/807—Steam

Definitions

• This invention relates to desulphu ⁇ sation and in particular to desulphu ⁇ sation of a hydrocarbon feedstock that is to be subjected to a downstream catalytic process, such as steam reforming Desulphunsation is necessary because many catalysts used for downstream processing of hydrocarbons are poisoned by sulphur compounds which are generally present in hydrocarbon feedstocks
• Some sulphur compounds such as hydrogen sulphide and carbonyl sulphide, can be removed simply by passing the feedstock through a bed of a sulphur absorbent at an elevated temperature
• a sulphur absorbent such as zinc oxide, carbonate or basic carbonate compositions are used for removing hydrogen sulphide and carbonyl sulphide at temperatures in the range 100 to 250°C
• Other sulphur compounds however, such as mercaptans, disulphides and thiophenes are not readily removed simply by such a sulphur absorbent
• it is conventional to subject the feedstock to a hydro-desulphu ⁇ sation step wherein the feedstock, together with hydrogen, is passed at an elevated temperature, typically in the range 150 to 300°C, through a bed of a hydro-desulphu ⁇ sation catalyst, typically a molybdate of cobalt and/or nickel
• the organic sulphur compounds are reduced, producing hydrogen sulphide, which can then be removed by a particulate
• hydro-desulphu ⁇ sation requires a source of hydrogen
• a source of hydrogen is available and indeed where the hydrocarbon feedstock is subjected to processes such as steam reforming, hydrogen is produced and some of this hydrogen can be recycled to provide the hydrogen required for hydro-desulphunsation
• EP1002779 describes a process wherein a hydrocarbon feedstock is subjected to hydro-desulphunsation, sulphur removal and catalytic steam reforming with recycle of a portion of the product reformed gas via an ejector, to provide hydrogen for the hydro-desulphunsation step
• US4976747 and US4181503 describe processes for producing hydrogen for fuel cells where oxygen is removed from natural gas by adding a hydrogen-rich gas to the natural gas and feeding the mixture to an oxidiser prior to hydrodesulphu ⁇ sation, hydrogen sulphide absorption, steam reforming and shift reactions
• the hydrogen-rich gas is provided by recycling part of the product from the shift reaction that follows the steam-reforming step In some processes however, recycle of hydrogen is incon
• the present invention is concerned with effecting desulphunsation where an external source of hydrogen is unavailable and recycle of hydrogen from downstream is inconvenient It has been proposed, in GB2050413, to remove organic sulphur compounds from a feedstock prior to reforming by subjecting the feedstock and steam to temperatures above 800°C in the presence of an alkaline absorbent disposed in the reformer tubes before the feedstock contacts the reforming catalyst This however necessitates the use of uneconomically large reformer units
• the present invention provides a process for the desulphunsation of a hydrocarbon feedstock containing sulphur compounds comprising subjecting a portion of said feedstock to a pre-treatment step of partial oxidation, optionally in the presence of a catalyst, or adiabatic low temperature catalytic steam reforming, thereby forming a gas stream containing hydrogen, and then passing the resultant hydrogen-containing pre-treated gas stream, together with the remainder of said hydrocarbon feedstock, through a bed of a hydro-desulphunsation catalyst and then through a bed of a particulate absorbent capable of absorbing hydrogen sulphide
• the hydrocarbon feedstock will normally contain hydrogen sulphide as well as organic sulphur compounds Typically, it will have a total sulphur content of 1 to 500 ppm by weight of which typically 50 to 90% is organic sulphur
• the invention is of particular applicability where the hydrocarbon feedstock contains no free hydrogen or an amount that is insufficient for adequate hydro-desulphunsation Generally the feedstock will contain less than 1 %, particularly less than 0 5%, by volume of hydrogen, but a hydrogen content in the range 0 5 to 1 5% by volume is desirable for adequate hydro- desulphu ⁇ sation
• the portion of the hydrocarbon feedstock subjected to the pre-treatment may be subjected to a step of desulphunsation using a particulate absorbent capable of absorbing hydrogen sulphide and/or some organic sulphur compounds prior to the aforesaid pre-treatment
• a particulate absorbent capable of absorbing hydrogen sulphide and/or some organic sulphur compounds
• a part stream taken from the hydrocarbon feedstock is subjected to the pre-treatment step
• the part stream subjected to the pre-treatment represents a minor portion of the stream, preferably 1 to 45% and more preferably 5 to 25% by volume of the total hydrocarbon stream
• Separation of the part stream from the feedstock may be effected by the use of a throttle in the main supply of feedstock to force the flow of a part stream through the pre-treatment step
• a steam ejector may be employed that uses a stream of steam to effect the driving force required to cause the part stream to flow through the aforementioned pre-treatment step
• the pre-treatment may be adiabatic low temperature catalytic steam reforming, which is often otherwise termed pre-reforming In such a process steam is added to the hydrocarbon feedstock and the mixture passed adiabatically at a inlet temperature in the range 300-600°C, particularly 400-550°C, through a bed of a low temperature reforming catalyst, which is typically nickel, ruthenium, platinum
• the pre-treatment may be partial oxidation wherein the feedstock is partially combusted with an oxygen-containing gas, e g air Steam may be added to the partial oxidation feed and, if desired, the partial oxidation may be effected in the presence of a suitable catalyst
• suitable partial oxidation catalysts include nickel, platinum, rhodium, ruthenium, indium and/or palladium on an oxidic support such as alumina, calcium aluminate cement, rare earth oxides, titania, zirconia, magnesia and calcium oxide
• suitable catalysts for partial oxidation include mixed metal oxides such as Perovskites and pyrochore materials
• the pre-treatment is preferably non-catalytic partial oxidation
• the pre-treated gas stream is mixed with the remainder of the hydrocarbon feedstock and then subjected to hydro-desulphunsation e g using a nickel and/or cobalt molybdate hydro-desulphunsation catalyst
• the proportion of feedstock that is subjected to the pre-treatment and the conditions employed for the pre-treatment are preferably such that the feed to the hydro-desulphunsation catalyst contains at least 0 5% by volume of hydrogen
• hydro-desulphunsation is effected at a temperature in the range 150 to 400°C
• hydrogen sulphide is removed from the gas stream by passage through a bed of a suitable particulate absorbent
• absorbents are compositions containing zinc oxide, zinc carbonate or basic zinc carbonate
• copper-containing absorbents may be employed In such copper-containing compositions, the copper will normally be in the reduced state as a result of the hydrogen present in the gas stream
• the copper-containing compositions may also contain
• the resultant desulphurised gas stream may be used for a variety of purposes but the invention is of particular utility where the desulphurised gas stream is to be subjected to steam reforming to produce hydrogen e g for use in a fuel cell, or synthesis gas for the production of methanol or ammonia or higher hydrocarbons, e g by the Fischer-Tropsch reaction
• Figure 1 is a diagrammatic flow sheet of a process in accordance with a first embodiment of the invention
• Figure 2 is a diagrammatic flow sheet of a process in accordance with a second embodiment of the invention
• Figure 3 is a diagrammatic flow sheet of a process in accordance with a third embodiment of the invention.
• a hydrocarbon feedstock is supplied via line 10 Part, for example 8% of the total, is taken via line 11 and mixed with steam supplied via line 12 and the resulting mixture fed via line 13 and heat exchanger 14 at an elevated temperature e g 400°C to a bed 15 of a low temperature reforming catalyst wherein reforming takes place adiabatically
• the reformed gas leaves bed 15 via line 16 and is re-united with the remainder of the hydrocarbon feedstock which bypasses bed 15 via line 17
• the resulting mixture which typically contains about 1 % by volume of hydrogen, is then fed via line 18 to a bed 19 of a hydro-desulphunsation catalyst wherein hydro-desulphunsation takes place and the organic sulphur compounds are converted to hydrogen sulphide
• the hydro-desulphurised gas is then fed, via line 20, through a bed 21 of a particulate hydrogen sulphide absorbent and then via line 22, through a bed 23 of a copper/zinc oxide absorbent to effect further sulphur removal to give
• a further bed of the hydrogen sulphide absorbent may be disposed in line 10 or line 11 to effect removal of any hydrogen sulphide in the hydrocarbon feed prior to contact with the low temperature reforming catalyst 15
• a throttle 25 needs to be disposed in line 17 so that some of the hydrocarbon feed is diverted through bed 15
• 100 parts by volume of natural gas are supplied to line 10 at a pressure of 2 bar abs and a temperature of 400°C
• the throttle 25 is arranged so that 8 parts by volume of the natural gas is diverted along line 11 and is mixed with 7 parts by volume of steam at 400°C at a pressure of 2 bar abs
• the mixture is fed through the bed of catalyst 15 whereupon reforming takes place to give about 17 4 parts by volume of a gas stream 16 containing about 8 1 parts by volume of a methane, about 1 1 parts by volume hydrogen, about 7 7 parts by volume steam, with the balance being carbon oxides
• the resultant gas stream contains about 1 0% by volume hydrogen
• an ejector 26, working on the ventu ⁇ principle is provided in the steam line 12 and the throttle 25 of the Figure 1 embodiment is omitted
• This ejector includes a constriction and expansion region through which the steam passes providing a region of lower pressure into which the hydrocarbon is fed via line 11
• the use of an ejector to control hydrocarbon feed to the low temperature reformer 15 may be preferable where the use of a throttle control is difficult
• the remainder of the process is identical to that depicted in Figure 1
• it may be inconvenient to recycle hydrogen from downstream of the processing of the desulphurised stream 24 in some cases it may be possible to arrange for recycle of sufficient of the adiabatically reformed stream 16 to provide sufficient hydrogen to enable the hydrocarbon feedstock fed to the adiabatic reforming step to be desulphurised
• an ejector 26 provided in the steam line 12 provides a region of lower pressure into which the hydrocarbon is fed via lines 10, 11 and 27
• the steam/hydrocarbon mixture is then pre-heated in heat exchanger 14 and fed, via line 28, to a first bed of a hydro-desulphunsation catalyst followed by a bed of a hydrogen sulphide absorbent, both disposed in a vessel 29
• the desulphurised steam/hydrocarbon mixture is then fed via line 13 to the bed 15 of low-temperature reforming catalyst Part of the reformed gas leaving bed 15 via line 16 is recycled to the ejector 26 via line 30 to provide the hydrogen required for hydro-desulphunsation of the hydrocarbon feedstock fed to bed 15
• Valves 31 and 32 are provided in lines 11 and 30 respectively to control the amounts of the feedstock stream and recycled hydrogen-containing stream fed to the ejector 26

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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)
• Hydrogen, Water And Hydrids (AREA)
• Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
• Glass Compositions (AREA)
• Superconductors And Manufacturing Methods Therefor (AREA)
• Amplifiers (AREA)
• Macromolecular Compounds Obtained By Forming Nitrogen-Containing Linkages In General (AREA)
• Transition And Organic Metals Composition Catalysts For Addition Polymerization (AREA)

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• 2001
  • 2001-02-09 EP EP01904157A patent/EP1255804B1/en not_active Expired - Lifetime
  • 2001-02-09 AU AU2001232074A patent/AU2001232074A1/en not_active Abandoned
  • 2001-02-09 WO PCT/GB2001/000564 patent/WO2001060950A1/en not_active Ceased
  • 2001-02-09 DE DE60100474T patent/DE60100474T2/de not_active Expired - Lifetime
  • 2001-02-09 JP JP2001560322A patent/JP5102420B2/ja not_active Expired - Fee Related
  • 2001-02-09 AT AT01904157T patent/ATE245182T1/de not_active IP Right Cessation
• 2002
  • 2002-08-19 US US10/222,905 patent/US20030000143A1/en not_active Abandoned

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