DE112007001743T5 - Hydrocracked - Google Patents

Abstract

A method of hydrocracking a hydrocarbonaceous feed comprising:
(A) introducing a liquid phase stream (1) comprising a hydrocarbonaceous feedstock, at least a portion of a liquid phase effluent (16) from a hydrocracking zone (13, 20) and hydrogen into a hydrotreating zone to produce hydrogen sulphide and ammonia, and providing a first hydrocarbon-containing stream (7) comprising hydrocarbons having a reduced level of sulfur and nitrogen wherein the hydrogen is in a concentration sufficiently low to maintain a continuous liquid phase system in the hydrotreating zone;
(b) introducing at least a portion of the first hydrocarbon-containing stream (7) containing hydrocarbons having a reduced level of sulfur and nitrogen into the hydrocracking zone (13), wherein hydrogen is present in a sufficiently low hydrogen concentration to provide a continuous flow To maintain liquid phase system in the hydrocracking zone;
(c) separating the hydrocarbonaceous stream selected from the group consisting of the first hydrocarbonaceous stream (7) comprising hydrocarbons which are ...

Description

FIELD OF THE INVENTION

The The present invention relates to the field of catalytic Conversion of hydrocarbons into useful hydrocarbon products. In particular, the invention relates to catalytic hydrocracking.

BACKGROUND OF THE INVENTION

The The present invention relates to the hydrocracking of hydrocarbonaceous feedstock. Oil refining companies often produce desired products, such. B. turbine fuels, diesel fuel and other products known as middle distillates, as well as Hydrocarbons containing low boiling point, such as B. naphtha and heavy fuel by hydrocracking a hydrocarbon feedstock, which is obtained from crude oil or heavy fractions thereof. Feedstocks most commonly hydrocracked are gas oils and heavy gas oils, obtained by distillation from crude oil. A typical heavy one Gas oil contains a substantial proportion of hydrocarbon constituents, boiling above 371 ° C (700 ° F), usually at least 50% by weight above 371 ° C (700 ° F) boil. A typical vacuum gas oil usually has one Boiling point range between 315 ° C (600 ° F) and 565 ° C (1050 ° F).

hydrocracking is generally achieved by incorporating in a hydrocracking reaction vessel or one zone the gas oil or other feedstock, which is to be treated with a suitable hydrocracking catalyst under conditions of elevated temperature and pressure in the Presence of hydrogen as a separate phase in a two-phase reaction zone is brought into contact so as to obtain a product which contains a distribution of hydrocarbon products, such as it is desired by the refinery. The operating conditions and the hydrocracking catalysts within a hydrocracking reactor affect the yield of hydrocracked products.

Usually becomes the fresh feed for a hydrocracking process first into a denitrification and desulphurisation zone introduced, which comprises hydrogen in a gaseous phase and in particular for the removal of sulfur and nitrogen contaminants is suitable and which subsequently in a hydrocracking zone which introduces a hydrocracking catalyst and Contains hydrogen in a gaseous phase. Another method for hydrocracking fresh feed is the fresh feed and the drain from the Hydrocracking zone in the denitrification and desulfurization zone contribute. The resulting effluent from the hydrocracking zone is separated to desired products, which is a hydrocracking and unconverted feedstock which was then introduced into the hydrocracking zone becomes. In the past, at least a major part of the hydrogen was in the reaction zones, in a gaseous phase available. This method or technique becomes general referred to as "trickle bed", wherein the continuous Phase is gaseous and not liquid.

Even though a large number of process flowcharts, Operating conditions and catalysts in commercial activities there is always a need for new hydrocracking processes, the lower cost, simplification of the structure, higher Yields of liquid products and products higher Quality result.

STATE OF THE ART

US 5,720,872 (Gupta) discloses a process for hydroprocessing liquid feedstocks in two or more hydroprocessing stages located in separate reaction vessels and wherein each reaction step contains a bed of hydroprocessing catalyst. The liquid product from the first reaction stage is placed in a low pressure stripping zone and hydrogen sulfide, ammonia and other dissolved gases are stripped off. The stripped product stream is then passed to the next downstream reaction stage, the product from which dissolved gases have also been stripped and sent to the next downstream reaction stage, to the final reaction stage, and gases dissolved from the liquid product thereof be stripped and which is collected or forwarded for further processing. The flow of the treatment gas is in a direction opposite to the direction in which the reaction stages for the flow of the liquid are arranged. Each stripping step is a separate step, but all steps are contained in the same stripping vessel.

US 3,238,290 (Hengstebeck) discloses a two-step hydrocracking process for hydrocarbons in which the feedstock is pretreated in a first stage.

US 5,403,469 (Vauk et al.) Discloses a parallel hydrotreating and hydrocracking process. Outflow from the two processes becomes combined in the same deposition vessel and separated in a vapor containing hydrogen and a hydrocarbon-containing liquid. Hydrogen is shown as part of the feed stream being fed to both hydrocracking and hydrotreating.

US 5,980,729 (Kalnes et al.) Discloses a hydrocracking process wherein a hydrocarbonaceous feedstock and the effluent from a hot hydrocracking zone containing hydrogen is passed to a denitrification and desulfurization reaction zone to produce hydrogen sulfide and ammonia to thereby supply the fresh feedstock clean. From the resulting hot, uncooled effluent from the denitrification and desulfurization zone, hydrogen is stripped in a stripping zone which is maintained at substantially the same pressure as the previous reaction zone with a gaseous stream rich in hydrogen to produce a vapor stream containing hydrogen, hydrocarbonaceous components boiling at a temperature below the boiling range of the fresh feedstock, hydrogen sulphide and ammonia, and a liquid hydrocarbonaceous stream containing unconverted feedstock. This liquid hydrocarbonaceous stream is introduced into a hydrocracking zone to produce an effluent from the hydrocracking zone, which is then combined with the fresh feedstock as described above, and subsequently introduced into the denitrification and desulfurization zone.

US 6,106,694 (Kalnes et al.) Discloses a hydrocracking process wherein a hydrocarbonaceous feedstock and effluent from a hot hydrocracking zone is passed to a denitrification and desulfurization zone to produce hydrogen sulfide and ammonia to thereby purify the fresh feedstock. From the resulting hot, uncooled effluent from the denitrification and desulfurization zone, hydrogen is stripped in a stripping zone which is maintained at substantially the same pressure as the previous reaction zone with a hydrogen-rich gaseous stream to produce a vapor stream which is hydrogen contains hydrocarbonaceous constituents which boil at a temperature below the boiling range of the fresh feedstock, hydrogen sulfide and ammonia, and a liquid hydrocarbonaceous stream containing unconverted feedstock. This liquid hydrocarbonaceous stream is then introduced into the hydrocracking zone to produce an effluent, which is then introduced into the denitration and desulfurization reaction zone as described above.

US 6,123,835 (Ackerson et al.) And US 6,428,686 (Ackerson et al.) Disclose a hydroprocessing in which the need to circulate hydrogen through the catalyst is eliminated by mixing the hydrogen and the oil feedstock in the presence of a diluent in which the solubility of hydrogen relative to the feedstock is high. The oil-diluent-hydrogen solution may then be fed to a tubular reactor containing a catalyst.

BRIEF SUMMARY OF THE INVENTION

The present invention is a catalytic hydrocracking process, in one embodiment, a stream of liquid Phase comprising hydrocarbonaceous feedstock, an effluent of a liquid phase from a hydrocracking zone and a sufficiently low hydrogen concentration to be a continuous system maintain a liquid phase in a hydrotreatment zone be introduced to hydrogen sulfide and ammonia to generate and generate a first hydrocarbon-containing stream, which includes a reduced level of sulfur and hydrocarbons Include nitrogen. The hydrocarbons have a reduced level of sulfur and nitrogen and become a hydrocracking zone introduced with a sufficiently low hydrogen concentration, to maintain a continuous system of a liquid phase to produce an effluent from a hydrocracking zone, which provides hydrocarbons with a lower boiling range. In preferred embodiments, the first hydrocarbon-containing Electricity that includes hydrocarbons that have a reduced level sulfur and nitrogen in a high pressure product scraper for products or by conventional distillation separated to provide hydrocarbons that have a reduced Level of sulfur and nitrogen, which subsequently be introduced into the hydrocracking zone.

In a second embodiment, the present invention is a catalytic hydrocracking process in which a liquid phase stream comprising a hydrocarbonaceous feed stream, effluent liquid phase from a hydrocracking zone, and a sufficiently low hydrogen concentration to maintain a continuous liquid phase system can be introduced in a hydrotreatment zone to produce hydrogen sulfide and ammonia, and to produce a first hydrocarbon-containing stream comprising hydrocarbons having a reduced level of sulfur and nitrogen material. The first hydrocarbonaceous stream comprises hydrocarbons having a reduced level of sulfur and nitrogen and is introduced into a hydrocracking zone having a sufficiently low concentration of liquid hydrogen to maintain a continuous liquid phase system to produce effluent from the hydrocracking zone. The effluent from the hydrocracking zone is introduced into a separation zone, one embodiment of which is preferably a high pressure product scavenger to produce a second hydrocarbonaceous stream containing lower boiling hydrocarbons and a hydrocarbonaceous liquid phase stream comprising unconverted hydrocarbons, and which the hydrotreatment zone is introduced as described above. Hydrocracked hydrocarbons boil at a temperature range lower than the recovered hydrocarbonaceous feedstock.

Conventional hydrotreating processes use trickle bed technology. This technology requires the use of large amounts of hydrogen relative to the hydrocarbon feed which sometimes exceeds 1685 nm ³ / m ³ (10,000 SCF / B) and necessitates the use of costly recycle gas compression. The high levels of hydrogen relative to the hydrocarbonaceous feedstock in conventional hydrotreating equipment make this type of equipment a continuous gas phase system. It has been discovered that it is neither economical nor necessary to have this large excess of hydrogen to accomplish the desired conversion. The desired conversion can be carried out with less hydrogen and can be carried out economically and with high efficiency with just enough hydrogen to ensure a continuous liquid phase system. A continuous liquid phase system would exist at one extreme with only enough hydrogen to fully saturate the hydrocarbon feed and at the other extreme, where sufficient hydrogen is added, to transition to a continuous gas phase system. The amount of hydrogen supplied between these two extremes is determined based on economic considerations. Operation with a continuous liquid phase system avoids the high costs associated with a recycle gas compressor.

Other Embodiments of the present invention include others Details, such. The nature and description of the feeds, hydrocracking catalysts, Hydrotreating catalysts and the preferred operating conditions, including the temperatures and pressures, all in the following discussion for each of these aspects of the invention.

BRIEF FIGURE DESCRIPTION

The Figures are more preferred in simplified process flow diagrams Embodiments of the present invention. It is intended, that the figures illustrate schematically the present invention, without being a limitation of the same. While the figures represent the process so that it is in one mode working with a downward current, this only serves for illustrative purposes, and it is not intended to be To exclude operation with an upward current.

DETAILED DESCRIPTION THE INVENTION

The Method of the present invention is particularly useful for hydrocracking a hydrocarbon oil which Comprising hydrocarbons and / or other organic materials, to produce a product containing hydrocarbons and / or includes other organic materials, with lower mean Boiling point and a lower average molecular weight. The hydrocarbonaceous feeds that undergo hydrocracking subjected by a method according to the invention All mineral oils and synthetic oils should be able to (eg shale oil, tar sand products, etc.) and fractions including it. Illustrative hydrocarbon feeds include those that include ingredients that are above 288 ° C (550 ° F) boil, such. B. atmospheric gas oils, Vacuum gas oils, deasphalted, vacuum and atmospheric residues, hydrotreated or mild hydrocracked residual oils, Koker distillates, straight run distillates, solvent deasphalted oils, Pyrolysis oils, synthetic oils high boiling point, cyclic oils and catalytic cracker distillates. A preferred hydrocracking feed is gas oil or another hydrocarbon fraction containing at least 50% by weight and most often at least 75% by weight, their constituents at a temperature above 371 ° C (700 ° F) boil. One of the most preferred gas oil feeds, which comprise hydrocarbons is above 288 ° C (550 ° F) boil, with the best results with feeds obtained, comprising at least 25% by volume of the constituents, between 315 ° C (600 ° F) and 565 ° C (1050 ° F) boil.

The selected hydrocarbon-containing Feedstock and hydrogen are introduced into a hydrotreating reaction zone at hydrotreating reaction conditions. In addition, the resulting effluent from a hydrocracking reaction zone described later is also introduced into the hydrotreating reaction area. Preferred hydrotreating conditions include a temperature of 204 ° C (400 ° F) to 482 ° C (900 ° F), a pressure of 3.5 MPa (500 psig) to 17.3 MPa (2500 psig) and an hourly liquid flow rate of the fresh hydrocarbon feedstock between 0.1 hr ^-1 to 10 hr ^-1 with a hydrotreating catalyst or a combination of hydrotreating catalysts. Only as much hydrogen is introduced into the hydrotreating reaction zone to maintain a continuous liquid phase system. That is, unlike conventional hydrotreating processes which operate in a trickle bed mode in which the gas phase is continuous, the present invention operates in a continuous liquid phase system.

Of the Term "hydrotreating" as used herein refers to a process wherein the hydrogen-containing treatment gas absorbed in liquid hydrocarbon material and in the presence is used by suitable catalysts, which primary are active for the removal of heteroatoms, such as. Sulfur and nitrogen from the hydrocarbon feedstock. Suitable hydrotreating catalysts for use in the present invention Invention are any known conventional hydrotreating catalysts and include those made from at least one metal of the group VIII, preferably iron, cobalt and nickel, and still More preferably cobalt and / or nickel and at least one metal from group VI, preferably molybdenum and tungsten, from a support material with a large surface, preferably alumina. Other suitable hydrotreating catalysts include Zeolite catalysts, as well as noble metal catalysts, wherein the noble metal is selected from palladium and platinum. It is still within the scope of the present invention that used more than one type of hydrotreating catalyst in the same reaction vessel becomes. The Group VIII metal is typically present in in an amount between 2-20% by weight, preferably from 4-12% by weight. The Group VI metal is typically present in an amount between 1-25% by weight, preferably from 2 to 25% by weight.

In an embodiment of the present invention is the resulting effluent from the hydrotreating reaction zone directly introduced into a hydrocracking reaction zone to hydrocarbons provide with lower boiling point. In another embodiment In the present invention, the resulting effluent becomes a Separation zone introduced, which is preferably is a high-pressure product scraper or a conventional Fractionation zone to low boiling point hydrocarbons to win back and a hydrocarbonaceous stream to provide hydrocarbons contained in the Boil the area of the fresh feed, which subsequently is introduced into a hydrocracking zone. The high pressure product separator is preferably at a temperature of 204 ° C (400 ° F) to 482 ° C (900 ° F) and a pressure of 3.5 MPa (500 psig) to 17.3 MPa (2500 psig).

In a preferred embodiment, at the outflow the hydrotreating zone introduced directly into the hydrocracking zone is, the effluent from the hydrocracking reaction zone is preferably introduced into a high pressure wiper, preferably at a temperature of 204 ° C (400 ° F) to 4892 ° C (900 ° F) and a pressure of 3.5 MPa (500 psig) to 17.3 MPa (2500 psig) is operated to a vapor produce hydrocarbonaceous electricity, as well as a liquid hydrocarbonaceous stream containing hydrocarbons, which boil in the area of the fresh feed which is in the hydrotreating zone is introduced. In a preferred Embodiment in which the effluent from the hydrotreating zone is separated between the hydrotreating zone and the hydrocracking zone, the effluent from the hydrocracking zone is sent directly to the hydrotreatment zone introduced.

In any event, the feedstock is introduced into the hydrocracking zone along with added hydrogen in an amount sufficiently low to maintain a continuous liquid phase system. The hydrocracking zone may contain one or more beds of the same or different catalysts. In one embodiment, when the preferred products are middle distillates, the hydrocracking catalysts use amorphous bases or bases having a low level of zeolite combined with one or more group VIII or group IVB metal hydrogenation components. In another embodiment, when the preferred products are in the heavy gasoline boiling range, the hydrocracking zone comprises a catalyst generally comprising any zeolite cracking base on which a minor amount of a Group VIII metal hydrogenation component is applied , Additional hydrogenation components can be selected from Group VIB for incorporation into the zeolite base. The zeolite cracking bases are sometimes referred to in the art as molecular sieves usually characterizes and consists of silica, alumina or one or more exchangeable cations, such. Sodium, magnesium, calcium, rare earth metals, etc. They are further characterized by crystal pores of relatively uniform diameter between 4 and 14 Angstroms (10 ^-10 meters). It is preferred to use zeolites having a relatively high silica / alumina mole ratio of between 3 and 12. Suitable zeolites found in nature include e.g. Mordenite, Stilbite, Heulandite, Ferrierite, Dachiardite, Chabazite, Erionite and Faujasite. Suitable synthetic zeolites include, for. B. the B, X, Y and L crystal types, z. Synthetic faujasite and mordenite. The preferred zeolites are those with crystal pore diameters between 8 and 12 Angstroms (10 ^-10 meters) with the silica / alumina molar ratio being between 4 and 6. A preferred example of a zeolite falling within this preferred group is a synthetic Y molecular sieve.

The naturally occurring zeolites are normally found in a sodium form, an alkaline earth metal form or mixed forms. The synthetic zeolites are almost always produced first in the sodium form. In any case, for use as a cracking base, it is preferable that most or all of the original monovalent zeolite metals be exchanged for ions with a polyvalent metal and / or with an ammonia salt, followed by heating to decompose the ammonia ions. which are in communication with the zeolite, leaving in their place hydrogen ions and / or exchange sites that are in fact decationated by the further removal of water. Hydrogen or "decationized" Y zeolites of this type are particularly useful in US 3,130,006 described.

mixed Polyvalent metal-hydrogen zeolites can be obtained by ion exchange be prepared with first an ammonia salt, then a partial Reverse exchange with a polyvalent metal salt and subsequent Calcination. In some cases, such as As is the case is synthetic mordenite, the hydrogen forms can through a direct acid treatment of the alkali metal zeolites getting produced. The preferred cracking bases are those which have at least 10%, and preferably at least 20%, are metal cation deficient, based on the original one Ion exchange capability. A particularly desirable stable class of zeolites are those in which at least 20% of the Ion exchange capacity satisfied by hydrogen ions becomes.

The active metals used in the preferred hydrocracking catalysts of the present invention are used as hydrogenation components, are those from Group VIII, d. H. Iron, cobalt, nickel, ruthenium, Rhodium, palladium, osmium, iridium and platinum. additionally These metals may also be related to this other accelerators are used, including the metals of Group VIB, z. Molybdenum and tungsten. The amount of hydrogenating Metal in the catalyst can change within these ranges. Generally speaking, each amount can be between 0.05 and 30% by weight. be used. In the case of precious metals is usually a Use of 0.05 to 2 wt .-% preferred. The preferred method to include the hydrogenating Me talls is that Zeolite base material with an aqueous solution a suitable constituent of the desired metal in To bring in contact with the metal in a cationic form is present. After the addition of the chosen hydrogenating Metal or metals becomes the resulting catalyst powder filtered, dried, with, if desired, added Lubricants, binders or the like in bead form brought, and in air at temperatures of z. B. 371 ° to Calcined at 648 ° C (700 ° -1200 ° F), to activate the catalyst and decompose ammonia ions. Alternatively, the zeolite component may first be beaded are formed, followed by the addition of the hydrogenating Ingredient and activation by calcination. The before described catalysts can in undiluted Form or a powdered zeolite catalyst can be mixed and beads are added with other, by comparison, less active catalysts, diluents or binders, such as. Alumina, silica gel, silica-alumina mixed gels, activated Lehmen or similar in circumstances between 5 to 50% by weight. These diluents can be applied as you are or you can lower Contain fraction of added hydrogenation metal, such as As a metal of group VIB and / or Group VIII.

Additional hydrocracking catalysts operating with metal accelerators can also be used in the process according to the invention, which is e.g. As aluminum phosphate molecular sieves comprises, crystalline chromosilicates and other crystalline silicates. Crystalline chromosilicates are described in more detail in US 4,363,718 (Klotz).

Hydrocracking of the hydrocarbonaceous feedstock in contact with a hydrocracking catalyst is conducted in the presence of sufficiently low concentrations of hydrogen to maintain a continuous liquid phase system, and preferably hydrocracking reactor conditions which maintain a temperature between 232 ° C (450 ° C) F) to 468 ° C (875 ° F), a pressure of 3.5 MPa (500 psig) to 17.3 MPa (2500 psig) and an hourly Liquid hourly space velocity (LHSV) of 0.1 to 30 hrs ^-1 . In accordance with the present invention, the term "substantial conversion to lower boiling point products" means that the conversion of at least 5% by volume of the fresh feedstock into products having a lower boiling point than the hydrocarbonaceous feedstock the conversion per pass in the hydrocracking zone is in the range of 15 to 75% Preferably, the conversion per pass is in the range of 20 to 60% Then the ratio of unconverted hydrocarbons boiling in the range of the hydrocarbonaceous feedstock, in hydrocarbonaceous feedstock between 1: 5 to 3: 5. The present invention is suitable for the production of naphtha, diesel or any other desired low boiling point hydrocarbons.

While transformations or reactions occurring in hydrotreating and hydrocracking reaction zones take place, necessarily Hydrogen consumed and must be replaced at one or more Hydrogen inlet points attached in the reaction zones are. The amount of hydrogen added to these places is checked, to make sure that the system as a continuous liquid phase system works. The limiting amount of hydrogen that added is, is the amount that causes a transition from a continuous liquid phase system to a continuous Gas phase system.

The relative amount of hydrogen that is needed to one continuous liquid phase system both in the hydrotreating as well as the hydrocracking zones, depends starting from the specific composition of the hydrocarbon Feedstock, the level or amount of conversion to hydrocarbon constituents with lower boiling point, composition and quantity hydrocarbons with low boiling point and temperature and the pressure in the reaction zone. Professionals in the field of Conversion and hydrocracking of hydrocarbons easily be able to set the appropriate amount of hydrogen, to provide a continuous liquid phase system, after all the above variables have been set.

BRIEF FIGURE DESCRIPTION

With reference to 1 For example, a feedstock stream comprising vacuum gas oil and introduced into the process via the line is shown 1 and mixed with an effluent from the hydrocracking zone, described hereinbelow, via the line 16 is transported. A gaseous stream, which is rich in hydrogen, is sent over the line 2 fed and combined with the feed stream and the resulting mixture and is passed over the line 3 in the hydrotreatment zone 4 introduced. Additional gas, which is rich in hydrogen, is sent through the pipes 5 and 6 in the hydrotreatment zone 4 introduced to supplement the required hydrogen which is in the hydrotreating zone 4 is consumed. The amount of hydrogen in the hydrotreating zone 4 is low enough to maintain a continuous liquid phase system. The resulting effluent from the hydrotreating zone 4 is over a line 7 transported and into the high pressure product scraper 8th introduced. A hydrocarbon-rich gaseous stream comprising hydrogen sulfide, ammonia, and hydrocarbons boiling in a range lower than that of the feedstock is passed over the line 9 from the high pressure product scraper 8th removed and recovered. A liquid hydrocarbonaceous stream contains hydrocarbon constituents which boil in the feedstock and is passed over the line 10 removed from the high pressure product scraper and with a hydrogen rich stream over the line 11 United and the resulting mixture is over the line 12 transported and introduced into the hydrocracking zone. Additional hydrogen gets over the pipes 14 and 15 to the hydrocracking zone 13 provided. The hydrocracking zone 13 provided hydrogen is present in an amount that is sufficiently low to maintain therein a continuous liquid phase system. The resulting effluent from the hydrocracking zone is from the hydrocracking zone via the line 16 removes and combines with fresh feed, which over the line 1 as described above.

With reference to the 2 It can be seen that a feed stream containing the vacuum gas oil passes through the line 1 is introduced into the procedure and over the line 16 is mixed with the effluent from the hydrocracking zone described below. A hydrogen-rich gaseous stream is provided over the line 2 and combined with the feed stream and the resulting mixture is passed over the line 3 transported and introduced into the hydrotreatment zone. Additional hydrogen will be 4 over the line 5 and 6 introduced into the hydrotreating zone. The total supply of hydrogen to the hydrotreating zone 4 is sufficiently low to maintain a continuous liquid phase system. A resulting effluent flow is via the line 7 from the hydrotreating zone 4 removed and will combined with a hydrogen-rich gaseous stream passing through the pipe 24 in an amount sufficiently low to maintain a continuous liquid phase system and the resulting mixture is passed over the line 25 transported and into the hydrocracking zone 20 introduced. Additional hydrogen becomes the hydrocracking zone 20 over the wires 26 and 27 in an amount sufficiently low to maintain a continuous liquid phase system herein. The resulting effluent flow is via the line 17 from the hydrocracking zone 20 removed and is combined with a hydrogen-rich gaseous stream, which via a pipe 18 is provided, and the resulting mixture is passed over the line 21 transported and into the high pressure product scraper 22 introduced. A hydrocarbonaceous vapor stream comprising hydrocarbons boiling in a region below the feedstock is removed from the high pressure product stripper 22 over the line 23 removed and recovered. A liquid stream comprising unconverted hydrocarbons is removed from the high pressure product scraper via the line 16 removed and fed to the feed stream which is via the line 1 as described above.

The The preceding description and the drawings clearly show the Advantages of the method according to the invention includes as well as the benefits that result from their use result.

SUMMARY

A catalytic hydrocracking process wherein a liquid phase stream comprising a hydrocarbonaceous feedstock ( 1 ), a liquid phase effluent from a hydrocracking zone ( 16 ) and hydrogen in a sufficiently low hydrogen concentration to maintain a continuous liquid phase system, a hydrotreating zone ( 4 ) to produce a first hydrocarbon-containing stream comprising hydrocarbons having a reduced level of sulfur and nitrogen. The resulting hydrocarbons have a reduced level of sulfur and nitrogen and are introduced into a hydrocracking zone ( 13 ) with a sufficiently low hydrogen concentration to maintain a continuous liquid phase system to provide a drain ( 16 ) from a hydrocracking zone which provides low boiling range hydrocarbons.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• US 5720872 [0006]
• US 3238290 [0007]
• US 5403469 [0008]
• US 5980729 [0009]
• US 6106694 [0010]
• - US 6123835 [0011]
• US 6428686 [0011]
• - US 3130006 [0023]
• US 4363718 [0026]

Claims (10)

A method of hydrocracking a hydrocarbonaceous feed comprising: (a) introducing a liquid phase stream ( 1 ) comprising a hydrocarbonaceous feedstock, at least part of a liquid phase effluent ( 16 ) from a hydrocracking zone ( 13 . 20 ) and hydrogen in a hydrotreating zone to produce hydrogen sulphide and ammonia, and a first hydrocarbonaceous stream ( 7 ) comprising hydrocarbons having a reduced level of sulfur and nitrogen, wherein the hydrogen is in a low enough concentration to maintain a continuous liquid phase system in the hydrotreating zone; (b) introducing at least part of the first hydrocarbon-containing stream ( 7 ), which contains hydrocarbons having a reduced proportion of sulfur and nitrogen, into the hydrocracking zone ( 13 ), wherein hydrogen is present in a sufficiently low hydrogen concentration to maintain a continuous liquid phase system in the hydrocracking zone; (c) separating the hydrocarbonaceous stream selected from the group consisting of the first hydrocarbonaceous stream ( 7 ) comprising hydrocarbons having a reduced proportion of sulfur and nitrogen and an effluent ( 17 ) from the hydrocracking zone into a separation zone ( 8th . 22 ) to provide hydrocracked hydrocarbons boiling in a temperature range lower than that of the hydrocarbonaceous feedstock; (d) recovering the hydrocracked hydrocarbons boiling in a temperature range lower than that of the hydrocarbonaceous feedstock; and (e) recycling at least part of the effluent ( 16 ) from the hydrocracking zone in step (a). The method of claim 1, wherein the hydrocarbon-containing Feed in the range between 315 ° C (600 ° F) to 565 ° C (1050 ° F) boiling. The method of claim 1, wherein the hydrotreating zone is operated under conditions that have a temperature of 204 ° C (400 ° F) to 482 ° C (900 ° F) and a pressure from 3.5 MPa (500 psig) to 17.3 MPa (2500 psig). The method of claim 1, further comprising Recovering unconverted hydrocarbons comprising in the range of the hydrocarbonaceous feedstock in one High pressure product scrapers boil. The method of claim 4, wherein the ratio the unconverted hydrocarbons, which are in the range of the hydrocarbon Boil the feed, the hydrocarbonaceous feedstock between 1: 5 to 3: 5. The method of claim 1, further comprising Recovering unconverted hydrocarbons comprising in the range of the hydrocarbonaceous feedstock in one Boiling fractionation zone. Process according to claim 1, wherein the hydrocracking zone operated at conditions that have a temperature of 232 ° C (450 ° F) to 468 ° C (875 ° F) and a pressure from 3.5 MPa (500 psig) to 17.3 MPa (2500 psig). The process of claim 1 which further comprises recovering unconverted hydrocarbons, hydrogen sulfide and ammonia from the hydrocarbonaceous stream boiling in the range of the hydrocarbonaceous feedstock and introducing unconverted hydrocarbons boiling in the range of the hydrocarbonaceous feedstock that in the hydrocracking zone ( 13 ) is recovered. The process of claim 1 further comprising introducing the first hydrocarbonaceous stream consisting of hydrocarbons having a reduced level of sulfur and nitrogen into a hydrocracking zone ( 20 ); Introducing the effluent from the hydrocracking zone into a separation zone ( 22 ) to a second hydrocarbonaceous stream ( 23 ) comprising lower-boiling hydrocarbons and a hydrocarbon-containing liquid-phase stream ( 16 ) comprising unconverted hydrocarbons; and introducing the hydrocarbon-containing liquid phase stream comprising unconverted hydrocarbons in step (a). The method of claim 9, wherein the deposition zone is a high pressure product scraper.