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
  • 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
  • C10G69/06—Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one other conversion process plural serial stages only including at least one step of thermal cracking 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
  • C10G2300/00—Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
  • C10G2300/10—Feedstock materials
  • C10G2300/107—Atmospheric residues having a boiling point of at least about 538 °C

Definitions

• the invention relates to a method for splitting hydrocarbon mixtures with a hydrogenating treatment and a subsequent thermal splitting.
• DE-A 2164 951 describes a process in which the insert is catalytically hydrogenated before it is thermally cleaved. This pretreatment reduces the aromatic compounds in the feed material, which essentially lead to the undesired cleavage products. In addition, the feed material is desulfurized.
• the invention has for its object to design a method of the type mentioned so that it can be operated under particularly favorable economic conditions.
• the hydrocarbon mixture is an atmospheric residual oil, from which a vacuum gas oil and a vacuum residue are formed in a vacuum distillation, that the asphalt components are separated from the vacuum residue and the asphalt-free vacuum residue is blended with the vacuum gas oil and fed to the hydrogenating treatment, after which at least part of the hydrogenation product is subjected to the thermal cleavage.
• the asphalt components are separated by means of solvent extraction.
• the extracted vacuum residue contains up to 40% by weight of paraffinic and naphthenic components which give high olefin yields during thermal cleavage.
• This fraction also has aromatics, essentially polyaromatics, which can be processed to cleavable components in the course of a hydrogenation.
• extraction residue which can be used as bitumen or can also serve as a hydrogen source for the hydrogenation if it is converted to a gas mixture via partial oxidation.
• the vacuum residue can be extracted with non-polar solvents. In an advantageous development of the inventive method this will be C J - to C6 hydrocarbons used.
• the yield of extracted vacuum residue, but also the content of heavy metal, asphalt, sulfur and nitrogen in this fraction increases with the number of carbon atoms in the solvent hydrocarbon used.
• the quality of the extracted vacuum residue after its blending with the vacuum gas oil determines the selection of the extractant for the particular hydrocarbon mixture used.
• the content of asphalt components and heavy metals should approximately correspond to the maximum permissible content of these components, below which the hydrogenation for normal catalyst run times (1 to 2 years) does not yet have any significant adverse effects on the hydrogenation reactions.
• maximum permissible levels are, for example, 0.05% by weight for asphalt components and in the order of magnitude of 2 to 3 ppm by weight for vanadium.
• the hydrogenating treatment of the blended vacuum gas oil and the extracted vacuum residue is carried out under reaction conditions in which only some of the hydrocarbons are converted to low-boiling products.
• the hydrogenation product is then broken down into a light and a heavy fraction, only the heavy fraction being fed to the thermal breakdown.
• This embodiment of the process is based on the knowledge that in the hydrogenation of a heavy hydrocarbon mixture not only the heavy constituents, in particular the polyaromatic compounds, are hydrogenated or hydrogenated, but also that isomerization of n-alkanes and n-alkyl chains also takes place.
• a product suitable for thermal cracking is first produced, but on the other hand, in the isomerization process, which increases with increasing hydrocracking sharpness during the hydrogenation, products are formed at the same time which only lead to slight increases in the cracking yields and because of their high hydrogen consumption limit the economics of the process.
• This procedure has the advantage, among other things, that the thermal cleavage can be carried out under particularly favorable conditions. Because the gap insert has a limited boiling range compared to the known method of DE-A 2164951, the gap conditions can be optimized better. In addition to the high yield of valuable products in the thermal splitting of the heavy boiling section, this procedure also surprisingly lowers the proportion of pyrolysis residues which are difficult to utilize and boil above 200 ° C.
• the separated low-boiling components of the hydrogenation product which are not fed to the thermal cracking, consist of gasoline fractions which are suitable as low-sulfur gasoline or turbine fuels or can be blended with other refined products suitable as fuel.
• these components are not already left in the heavy fraction, middle distillates are obtained which meet the requirements for heating oil of the specification EL and for diesel fuel.
• These fractions are particularly valuable due to their low sulfur content. However, they can also be blended with other sulfur-rich products in order to upgrade them economically.
• the quality of the hydrogenation product depends essentially on the reaction conditions of the hydrogenation. It is advantageous to control the hydrogenation in such a way that the undesired polyaromatic compounds of the hydrocarbon mixture used are largely hydrogenated, whereas the content of monoaromatic compounds is hardly changed. Since most of the monoaromatics get into the low-boiling fraction when the hydrogenation product is broken down, its motor properties are improved. In addition, hydrogen is not unnecessarily used for the monoaromatic hydrogenation in such a process.
• a favorable hydrogenation product results, for example, from the blending of vacuum gas oil and unextracted vacuum residue during hydrogenation under mild conditions, ie at temperatures between 350 and 400 ° C. a pressure between 80 and 150 bar and at space velocities of more than 0.7 I / I catalyst material and hour when using conventional hydrogenation or hydrocracking catalysts.
• the fraction with the low-boiling components either those below 200 ° C. or the components boiling below 340 ° C. If the cut is carried out at 200 ° C, a gasoline fraction results, which in turn can be broken down into a light gasoline and a heavy gasoline fraction.
• the cut below 340 ° C also contains kerosene and heating oil of the specification EL or diesel fuel.
• the vacuum residue was then treated with an extractant which consisted of 35 mol% propane and 65 mol% butane.
• the process was carried out in a countercurrent extraction column under a pressure of 30 bar, the temperatures in the sump being 45 ° C. and in the top of the column 75 ° C.
• This fraction was then hydrogenated.
• the mixture was passed at a pressure of 80 bar and at a temperature of 400 ° C at an hourly space velocity of 0.8 liters of hydrogenation per liter of catalyst material over a catalyst which contained nickel and molybdenum on an acidic carrier as hydrogenation-active components.
• a catalyst which contained nickel and molybdenum on an acidic carrier as hydrogenation-active components.
• 275 Nm 3 of hydrogen were consumed per ton of hydrogenation insert.
• the hydrogenation product contained 2.2% by weight of H 2 S, 0.1% by weight of NH 3 , 2.4% by weight of C 1 -C 4 hydrocarbons, and 30.4% by weight of liquid constituents.
• the insert was diluted with 0.8 part by weight of water vapor per part by weight of hydrocarbon and passed through the reactor with a residence time of 0.2 seconds.
• the outlet temperature was 830 ° C.
• the cleavage product contained valuable components of 9.5% by weight of methane, 28.1% by weight of ethylene and 14.8% by weight of propylene.
• the residue fraction boiling above 200 ° C only made up 12.3% by weight of the cracking insert.

Landscapes

• Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (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)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (2)

Family

ID=6051645

Family Applications (1)

Country Status (5)

Families Citing this family (23)

Citations (4)

Family Cites Families (8)

• 1978
  • 1978-10-06 DE DE19782843793 patent/DE2843793A1/de not_active Withdrawn
• 1979
  • 1979-10-01 JP JP12670179A patent/JPS5550089A/ja active Pending
  • 1979-10-03 EP EP79103767A patent/EP0009809B1/de not_active Expired
  • 1979-10-03 AT AT79103767T patent/ATE678T1/de not_active IP Right Cessation
  • 1979-10-03 DE DE7979103767T patent/DE2962096D1/de not_active Expired
  • 1979-10-09 US US06/082,454 patent/US4257871A/en not_active Expired - Lifetime

Patent Citations (4)

Non-Patent Citations (5)

Also Published As

Similar Documents

Legal Events