DE2259589A1 - PROCESS FOR THE PRODUCTION OF ASPHALTIC HEATING OIL - Google Patents

Description

Process for the production of fuel oil containing ajphalt

For this application, priority will be given on December 8, 1971 from the United States patent application Serial. No. 205 79.1 to complete

taken. _ ■

The invention "relates to a method zur'Herstellung of crude or residual oils of in particular ¹ low sulfur content. In particular, the invention relates to a method for hydrogenating desulphurisation for the manufacture of asphalt- containing • fuel oil of low sulfur content.

Various processes are known for the hydrogenative desulfurization of petroleum hydrocarbons, according to which Sulfur can be found in a very effective way in easier distillation fractions can be withdrawn, which v / earth obtained by distillation of crude oil. Contain crude oil and topped crude oil fractions but a heavy residue fraction that is above 560 ° C boils and is commonly referred to as "asphalt". As a result the presence of this faction makes the oil much harder desulfurize. Asphalt is generally a little valuable full material that is isolated from crude oil and used for road building is used. Perner is known to asphaltic fractions to convert the crude oil into more valuable products such as heating oil. However, if asphalt is isolated, it is extremely viscous and is difficult to process with catalysts. Furthermore, asphalt consists of large molecules with condensation

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aromatic rings and contains most of the total sulfur content of crude oil. Another problem is that some of the sulfur content of the asphalt is inside the large molecules is bound, vas the desulphurisation of the asphalt even more difficult. Asphalt also contains metals, mainly nickel and vanadium, which easily deposit on the desulphurisation catalysts and deactivate them. All of these factors have the effect that the conditions for removing the sulfur from heavy, asphaltic oils are much harsher in the form of higher temperatures and pressures as well as other catalysts are required than for the desulfurization of distillate oils. . ". ·

Sulfur is a major cause of air pollution. Therefore, some municipalities prescribe an upper limit for the sulfur content of heating oils. So far, such authorities have set an upper limit of 1 percent by weight for heavy fuel oils; the tendency, however, is to reduce the maximum permissible sulfur content even further, for example to 0.55%. Such limits represent an obstacle to the use of heavy arphaltic hydrocarbon oil fractions as heating oil, because asphaltic heating oils with sulfur contents of 0.5 ^c ß> cannot easily be produced from crude oils with such a high sulfur content by passing the crude oil over a desulfurization catalyst.

So far it has been possible to reduce the sulfur content of a special asphaltic crude oil or topped crude oil to 1 percent by weight by hydrogenating desulphurisation; However, if the sulfur content was to be reduced even further, the desulphurisation temperature had to be increased to such an extent that excessive hydrogenative cleavage to lower-boiling products took place. Although it was relatively easy to reduce the concentration of such residues from 4 to 1 percent by weight without excessive cleavage of the starting material, it is much more difficult for the majority of the typical starting materials to give them more than about Vj ^{ / j your .:; • To remove sulfur content. Too strong a hydrating £! Pc: l-

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However, processing is undesirable because it unnecessarily consumes hydrogen and leads to the formation of undesirable light products and coconut deposits on the desulfurization catalyst. It can also happen that this changes the type of product so far that you no longer get a heavy fuel oil; have heavy oils! but a higher calorific value -as lighter in the P _L e ~ gel oils.

Other methods that have been tried to get such asphalt To largely desulfurize fractions, mixing the asphalt-containing hydrocarbon oil with is practical sulfur-free distillate oils of medium boiling point and, the hydrofining of asphaltenic oils under conditions in which the asphaltic material is split by hydrative cleavage completely converted into lower boiling hydrocarbons will.

There is therefore a need for a process for the desulfurization of asphalt-containing hydrocarbon oils in order to make them more suitable for use as heavy fuel oils without it being necessary to mix them with light oils or to convert their asphalt content into lower-boiling products of completely different ones ! "Hatur to convert while e.g having to accept premature deactivation of the catalyst. '. .. .- · -

It has now been found that a certain heavy fuel oil, which contains an asphalt fraction and a sulfur content of less than 1 percent by weight, can be prepared by using an asphalt-containing hydrocarbon " oil, such as crude oil or residual oil (topped off crude oil), which contains more than about 1 percent by weight of sulfur, together with hydrogen " passes through a first hydrogen desulphurisation zone and out of the first hydrogen desulphurisation zone a first discharge of hydrogen sulfide, a light Gan fraction, an aromatic and saturated hydrocarbons containing oil fraction and a higher-boiling asphaltic fraction, the lower one Has sulfur content than the starting material. Hie oil fraction

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becomes different from the higher-boiling asphaltic Fraction referred to as "light oil". The hydrogen sulfide, the light gas fraction and the low-boiling part of the Light oil fraction are separated from the first drain, and the rest of the first drain, from the asphaltiochen Fraction and the higher-boiling part of the oil fraction, is passed through a second zone of hydrogenating along with hydrogen Desulfurization directed. Each of the hydrogen desulfurization zones contains a catalyst for the hydrogenating desulphurisation which is on a support without cracking activity. From the second zone of the hydrating Desulfurization is becoming a heavy duty, containing asphalt subtracted that contains less than 1 percent by weight sulfur.

Surprisingly, it was found that the measure a certain part of the normally liquid light oil fraction, which contains both aromatics and saturated hydrocarbons with boiling points below that of the asphalt fraction contained in the original crude oil or topped off crude oil contains, to remove before this crude oil together with the asphalt fraction of the second zone of hydrogenation Desulfurization is supplied, leads to the fact that the sulfur content of the heavy fuel oil thus obtained is easier and with less catalyst anter 1 $, e.g. below 0.5 or even less than 0.3 percent by weight, than is possible in a single reaction zone. By removing the Light oil fraction are also at the same time the entire hydrogen sulfide and removing any light hydrocarbons formed in the first stage of the process so that this Material does not even enter the second process stage.

According to one embodiment of the invention, one leads an asphaltic hydrocarbon feed with a Sulfur content of more than 1 percent by weight in a hydrogen desulfurization zone in the presence of hydrogen and a light oil fraction, the aromatics and saturated hydrocarbons with boiling points below that of the asphaltic part of that of the hydrodesulphurisation zone

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contains led feed, and controls the amount of this Light oil and therefore the amount of aromatics and saturated hydrocarbons that the Zor.e of the hydrogenating desulphurisation are supplied so that the desulfurization rate is increased and a heavy, asphalt-containing hydrocarbon fuel oil with a sulfur content of less than about 1 weight percent wins.

The method according to the invention is therefore obtained an asphalt-containing heavy heating oil that is practically sulfur-free, without the asphalt-containing heating oil with a sulfur-free one Having to mix distillate oil of medium boiling point in order to obtain an oil with a low sulfur content, although this Mixing measure is not excluded within the scope of the invention.

Another embodiment of the invention "relates to a Process for controlling hydrodesulphurisation of asphaltic pavement Heavy oils, which consists of using a crude oil or residual oil, e.g. an oil that has an aephaltic Contains fraction, in the presence of hydrogen passes through a zone of hydrogenation desulphurisation, the aromatic content of the oil increases as it passes through the hydrodesulphurisation zone, and that the aromatic content of the Oil as it passes through the hy4sdgrenden desulphurisation zone monitored and the oil is withdrawn from this zone at the point beyond which the aromatic content is not continues to increase.

The term "asphalt" or "asphaltic" includes those in Resins and asphaltenes contained in crude oil. The proportion of asphalt in the crude oil can be approximately 5 to 30 percent by volume or more, and the asphalt has an initial boiling point of about 560 C. It is used in refineries by deasphalting with Propane (solvent extraction) or obtained from distillation residues. The 'asphaltenes are highly aromatic, consist of large molecules with condensed aromatic rings and have all of the constituents of all crude oil usually the highest concentration of sulfur. ' To the under-

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Unlike other crude oil fractions, the asphalt also contains metals, mainly nickel and tanadium. The As-

Phaltenes and resins are therefore different from the rest of the crude oil, which is made up of "saturated hydrocarbons" and "aromatics" "consists in that the aromatics and saturated hydrocarbons are soluble in propane, while the asphalts and resins are insoluble in propane.

The propane-soluble "aromatics" include benzenes, naphthalenes, thiophenes, benzothiophenes and dibenzothiophenes as the main types of molecules, while in addition to the "saturated hydrocarbons" the non-aromatic ones, soluble in propane Hydrocarbons such as naphthenes, e.g. cyclohexanes, and the paraffins, κ.B. Dodecane, as well as sulfur compounds, such as butyl mercaptan. This is commonly referred to as "asphalt" The material is therefore the residue from the propane extraction. On the other hand, the resins and Aspnaltene can be separated from each other by extraction with pentane, because the asphalt ene are insoluble in pentane, while the resins and oils are soluble in pentane.

It is known to bring crude oil or topped crude oil, which contains the asphaltene fraction, to a lower sulfur content by means of hydrogenating desulphurisation. For this purpose, the crude oil or the topped off boil is passed together with hydrogen over metal catalysts of Group VI and Group VIII of the Periodic Table on a catalyst carrier without cracking activity, such as aluminum oxide, the sulfur content being relatively easy to reduce from 4 to about 1 percent by weight, which corresponds to a sulfur removal of 75 i ° . Once a certain starting material, such as a Kuwait crude oil, has been withdrawn from its sulfur content, the sulfur contained in the starting material suddenly becomes very resistant to further desulphurisation, and further sulfur extraction can only be achieved with considerable hydrogenative cleavage so that a lot of hydrogen is consumed and the nature of the product changes. The point at which the in the crude oil

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remaining sulfur can vary depending on the type of crude oil. This point can easily be determined by experiment. As already mentioned, the asphaltenes consist of large molecules with condensed aromatic rings and contain sulfur inside these large molecules, so that the sulfur is extremely difficult to remove from them. Furthermore, the asphalt contains all the metals, such as nickel and vanadium, which are found in the crude oil, and these metals are easily deposited on the catalyst and make it less effective. Therefore, more severe conditions in the form of higher temperatures and pressures are required to remove more than 13 ° of its sulfur content from the asphaltic oil, and such severe conditions lead to hydrogenative cleavage, i.e. to a separation of the carbon-carbon bonds of the asphaltene molecules with a reduction in molecular weight of the product, but not to desulphurisation by breaking carbon-sulfur bonds. ■ -

To further explain the invention, reference is made to the drawings. -

Pig. 1 is a flow diagram of the desulfurization of a asphaltic topped crude oil in two stages.

Fig. 2! shows graphically the percentage yield above the onset of boiling of that fed to the sulfurization reactor Feeding of boiling substances with increasing mean reactor temperature.

Fig. 3 graphically shows the change in concentration aromatic, saturated, asphaltene and resin fractions of an asphaltene-containing topped crude oil with increasing Degree of sulfurization.

Fig. 4 graphically shows the percentages by volume Aromatics and saturated hydrocarbons, which are different Stripping temperatures are driven off between the process stages.

5 through 9 are flow diagrams of processes for producing a light, aromatic-rich fraction of low

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according to the sulfur content of a part of the starting material, to the Solution of the asphaltenes and resins in the residue part of the starting material to make them thinner "before the asphaltenes and resins are desulfurized.

A topped crude oil, like a 50 # topped Kuwait crude oil, all of the asphalt of the original crude oil and therefore all of the nickel and vanadium as well as the mostly the "permanent sulfur content of the original 3'vohölj is supplied through line 10 (Fig. 1) and through line 14, preheater 16, line 18, solids Filter 20 and line 22 conveyed into drum 24. From the drum 24, the liquid oil passes through line 26 to Feeding pump 30.

The liquid discharged by the pump 30 is ridden hydrogen supplied through line 32 is mixed and passed through line 34, valve 36 and line 38 into furnace 40. The liquid valve 36 is not completely located in one preheat pipe for liquid hydrocarbons. Recirculated water and (if necessary) supplementary water material v / grounding of the liquid reactor charge before it is preheated added. The circulating hydrogen flows through line 42 and valve 44, while the supplemental hydrogen flows through line 46, compressor 48 and valve 50 can be added. Circulatory v / asBorotoff and supplements imgciv / assei * - Substance will be in the relatively cool liquid container introduced through line 32

The preheated mixture of liquid feed and hydrogen in line 54 may optionally contain a (not shown) protective reactor has been supplied. The expiration of to the. Slurry reactor is fed into the main reactor 60, which contains the catalyst beds 62, 64 and 66. This stream can e.g. have a boiling range from 343 C upwards

The to hy d. riere η den En tschwef ο 1 ung ν e rw ende te Ka ta 1 y ι ; A tor is of the conventional type and contains, for example, metals from Groups VI and VIII of the Periodic Table on a plate without any cleavage activity. The catalyst can, for example, from IUekel · · Ko--

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balt molybdenum or cobalt molybdenum exist on an alumina carrier. The alumina can be stabilized with 1 to 5 weight percent silica. The preferred catalyst is a nickel-cobalt-molybdenum catalyst au: ^p . ^v Aluminum oxide, which contains less than ι percent by weight silicon dioxide, and can optionally be sulfided. Another carrier without fission activity is magnesia. A particularly preferred catalyst is described in US Pat. No. 3,562,800 and consists of particles with diameters of about 0.64 to 1.3 mm. The same catalyst or different catalysts can be used for the hydrogenated desulphurisation in all process stages.

An essential feature of the invention is that the catalyst has a carrier without cleavage activity, because there is practically no cleavage in the process and very little material with a boiling point lower than the initial boiling point of the starting material is produced target. However, higher-boiling proportions of the original product can be are split into lower-boiling products, provided that these are still in the boiling range of the starting material. On the contrary to known processes in which, for example, high silica catalysts, for example 10 $ or more silica included, for hydrative cleavage aei? Asphaltene-des Starting material used v / earth, it coincides with that Method according to the invention mainly only for a Separation of the carbon bonds of the asphaltenes and Resins, so the swore desulphurable asphalt desulphurized becomes, but not to a split of Kohlonotoff'-Koh- ' Lens binding, which would lead to the Pd-Id υπg of products of lower molecular weight. In the gornäsü procedure the invention naturally removes sulfur from the oils; but this type of deprivation of swell is relatively easy easy to get to. With other Viorten: By splitting- "carbon-carbon failures, as in well-known Orack processes, entrjtehb a product other than heavy fuel oil, and f.; ο'J oh, o ancestors are not within the scope of the invention. Lei

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the present proceedings result in relatively little Material with boiling points below the onset of boiling of the the starting material fed to the hydrogenating desulphurisation system.

V / i3 already mentioned, the hydrogen is supplied through line 32 together with the starting material. In the reactor for the hydrogenating desulphurisation one works under conventional reaction conditions, for example at a pulp partial pressure of 70 to 350, preferably of 70 to 210 kg / cm. Oxygen partial pressures of 105 to 175 kg / cm are particularly preferred. The gas circulation speed can be 3> 56 bif. Amount to 356 Nm / 1 100, and preferably from 53.4 to 178 Nm ^5/100 1, and preferably contains the gas 85 '/' or more Y / ascerstoff. The molar ratio of hydrogen to oil can be between about 8: 1 and 80: 1.

It is an essential feature of the invention that a hydrogen partial pressure of at least 70 kg / cm "must be applied. If one wants to desulfurize the asphaltic oil to the required degree, this minimum hydrogen partial pressure must be applied in order to deliver the hydrogen to the The activity of the hydrogenating desulphurisation is not determined by the total reactor pressure, but by the chemical activity, expressed by the partial pressure of hydrogen.

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225958a

The temperatures in the reactor in which the hydrogenating Desulfurization "takes place, can be in the range of -about 343 to 482 ° C - and are preferably in the range of about 360 to 427 ° C.

Of the in I ¹ Ig. The catalyst beds 62, 64 and 66 shown in T can each have a larger volume than the previous bed. 4 "to 6 catalyst beds may be arranged reactor, and each catalyst bed may be a .to 25 ^, 50 £, 100 f or more larger amount of catalyst contained as the immediately preceding: Optionally, in the.

Since no protective chamber is present, line 54 · leads directly to the reactor. The outflow in line 54 mixes with the hydrogen stream from line 67 * valve 69, line 70 and valve 72, so that a mixture of hydrocarbons and hydrogen is fed to the top of the reactor through line 74. When passing through the catalyst bed 62, this stream is heated as a result of the exothermic reaction of the hydrogenating desulphurisation- .. The temperatures between the. Various catalyst beds can be controlled by direct cooling "with hydrogen", which is fed through line 76, valve 78, distributor 80 and line 82, valve 84 and distributor 86 '. Finally, the reaction mixture flows through the catalyst bed 66 and then, z * B "with a sulfur content of about 1 percent by weight, from the reactor.

Pig, 2 zo the following: If an asphaltic crude oil residue containing 4 ¹ P sulfur, by passing it through a hydrogenating desulfurization zone, such as the reactor 60 do ?: Pig. I _{5 is processed} into a product containing 1 percent by weight of sulfur and boiling above 3Ί9 ° C, - siedoii well over 80 ψ of this product at and above 349 ° 0 (the boiling point of the starting material) if the mean reactor temperature is increased by the alteration of the catalytic converter,? But as soon as the reaction temperature is increased to 427 C, there is an excessive hydrogenation]! Cleavage from lower-boiling products. this leads to

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a drop in the curve due to the formation of products that boil below the onset of boiling of the starting material. At this You can use a product boiling above 349 C with a point A sulfur content of 1 percent by weight can only be achieved at the expense of an excessively strong hydrogenating cleavage,

Wild Yfie shown below, the method of the invention enables the effective geraäss l'ntzug of defense as 7II i ³ of the sulfur contained in asphaltischcn oils and avoids the dioser by the wedge resistant oils related difficulties.

The drain withdrawn through line 88 (Pig .. 1) is a high-pressure expansion evaporation channel 90 is supplied, in which the light hydrocarbon gases, the hydrogen sulfide, the hydrogen and a controlled part in proportion highly desulphurize ^ saturated and aromatic Hydrocarbons driven off through line 92 will. The application of this relaxation evaporation 90 between the process stages is an essential feature of the invention. Careful selection of the stripping temperature the correct amount of light oil from the feed is determined at the respective process pressure de :: second procedural stage must be removed. The reason for distilling off a certain amount of light oil results from Fig. 3-

In Fig. 3 is the composition of a boiling above 343 G hydrocarbon oil, the various proportions of aromatics, saturated hydrocarbons,. . Containing resins and Asphaltcnen, shows in its passage through a reactor for hydrodesulfurization, as the reactor 60 of the Pig c "ι represented ο Vf ie Pig 3, the resin and Asphaltongehalt takes de; ο starting material with increasing sulfur ™ ent constantly decreasing, because connotoff-sulphurous amine-like g, etrormt and thus! "olokülbruchtcilc are broken off. Organic accumulation of these J-iolckülfreile is reflected in the increase in the amount of gou-saturated u) id aromatic 'liahlenw'OAMK'.v * - Substances, especially aromatics, of lower molecular weight. This increase in the aromatic content of the liquid, i

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advantageous because the aromatics represent a solvent for the extremely viscous resins and asphaltenes, which do not dissolve in saturated hydrocarbons. The desulfurization of any fraction proceeds to a sulfur removal of $ 75, and at this point the curves for the resins and asphaltenes reach a plateau which indicates that no further fragments are split off from them the total content of aromatics and saturated hydrocarbons does not increase any further; an increase in saturated hydrocarbons goes hand in hand with a decrease in the aromatics content. This "means that with a swell of" 75 ° the aromatics tend to saturation, which not only means a useless consumption of hydrogen, but also robs the remaining resins and asphaltenes of their aromatic solvent, while only the Amount of saturated hydrocarbons is increased, which act as a mere dispersant. With 75 percent sulfur removal, the sulfur compounds become resistant to further desulfurization, so that further "desulfurization goes hand in hand with a decrease in the aromatic content and a sharp increase in saturated hydrocarbons. Both factors are, for the further removal, of sulfur and for the Overcoming the difficulties caused by the great resistance of the oil at this point, which are disadvantageous, because when 75% of the sulfur content is withdrawn, most of the sulfur that has not yet been withdrawn is enriched in the resins and asphaltenes the viscous resins and asphaltenes are less well kept in solution, while the formation of saturated hydrocarbons leads to too strong a dispersion, so that the remaining sulfur compounds are too diluted and the reaction rate decreases as a result «,

Therefore, when operating the first desulfurization ^ - roaktoi-ö the aromatic content of the oil during its passage determine by the reactor, and the oil is supposed to get out of the reactor b if its aromatic content is no longer

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increases. This is according to Pig. 3 the case with 75 percent desulfurization. The aromatics content of the oil can increase by 25 to 40 percent by weight or more as it passes through the reactor. Even a slight increase in the aromatic concentration of, for example, 2 to 5 or 10 percent by weight is already advantageous. However, the aromatics content should not increase so much that the aromatics dilute the sulfur compounds to be removed too much.

It is assumed that up to 75% of the sulfur deprivation consists in the splitting off of edge sulfur from the complicated heterocyclic ring structure of the asphaltene molecule with the simultaneous formation of aromatic hydrocarbons, mainly as a result of the separation of carbon-sulfur bonds on the aromatic rings on the edge of the molecule. This production of aromatics is important because asphaltene molecules tend to form colloidal crystallites or aggregates, \ *. ^r they not hen there are a sufficient Lösungszustanü. Therefore, it comes to a ■ sulfur removal of 75 i * to a sufficient Aromatics in place, the asphaltene particles to hold in solution and di3 to for the desulfurization of the asphaltenes required action of Y / assorstoff and catalyst on the inner heterocyclic sulfur enable. With this 75 percent desulfurization, the ratio of aromatic to saturated hydrocarbons is so low that there is not enough solvent, but too much diluent, to remove the permanent sulfur.

Therefore it is necessary to check the aromatic content of the asphaltic Keep feed to the second hydrogen desulfurization zone under control. This can be done by one a controlled amount of the normally liquid oil product the first demolition zone aborts or otherwise separates it, ζ.Β «by distillation or relaxation voi-steaming u) id subsequent partial condensation of the driven off hydrocarbons, 'with recycling to achieve that Electricity has the correct aromatic content.

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It is therefore essential that the second Desulfurization reactor contains so much aromatics that the Resins and asphaltenes kept in solution in the oil, and all asphalt aggregates that have already formed, for example, again being divided up and brought into solution »At any given stripping temperature, a certain Amount of aromatic hydrocarbons - normally Ciine an even larger amount of saturated hydrocarbons aborted. In the case of certain crude oils, this rapid evaporation may result in · more aromatic than saturated Hydrocarbons, driven off advertise, and in this The advantage of this entapojination evaporation lies everywhere. only in the removal of excess dispersant. In practice, a compromise must be made by the second desulfurization stage together with the feed a sufficient amount of aromatics is supplied to keep the resins and asphaltenes in solution in sufficient quantity and properly desulfurized without losing the amount the aromatics is so large that the total amount of aromatic and saturated hydrocarbons fed into the second stage the sulfur compounds to be extracted from the oil are too diluted and dispersed, and thereby the rate of reaction reduced. The volume of. aromatic or ,, saturated hydrocarbons, which at a given Output temperature removed is shown in Hg »4» .

The solid lines in lig. 4 show a Mayse the content of the effluent from the first desulphurisation stage of saturated and aromatic hydrocarbons for various, Take-off temperatures measured at atmospheric pressure “If the output temperature is between the two stages of the process 260 ° 0, all boilers above 260 ° C get Aromatics -in the "second- Ygrfahroasstufe and are there available for solvating the resins and asphaltenes. P> e: L at an output temperature of 260 ° 0, however, the hydrocarbon exists Electricity to 8t volume percent from saturated hydrocarbons and 19 volume percent from aromatics, through this

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Amount of aromatics along with the even more. Larger amounts of saturated hydrocarbons, which accompany the aronattliger, can, however, be diluted too much with the asphaltic properties, so that the reactivity drops. When the Autriebstemperatur "wipe the drive step Ver the other hand, 427 ° C, uas ratio of aromatic au saturated hydrocarbons in the second 4p Ölbe destiny ARBITRATION is tuft _'f higher what solvation under light ringing Irnöglichcr dilution in itself is low. On the other hand, it can be the case that the 'G & including = * amount of aromatics that enter the second process stage, at a stripping temperature of 42? C is not large enough to dissolve the resins and Aöphalbene ku and reduce their viscosity so low that the desulphurisation is OK. So you have to find the right balance between sswischttt tables and saturated hydrocarbons in order to achieve the most favorable desulphurisation 7M gust figure. l ^ Punlit can be determined well by experiments with the respective au desulfurndett. If you have to use the residue, which is given by the diögenen lines In Pig. The distillate shown in 4 corresponds to that the best results are obtained by the eleventh Etttöpannün ^ över * - attenuation at flor that temperature which, regardless of the pressure at which the Entöpannimgsverdaiiipfung takes place, results in a separation at about 343 0. In this way, one obtains not only a sufficient total amount of aromatics in dom Verfahreruistrom, but also a V / erhältniü of about 12 Yölüin- * proficnt saturated ICohlonwatiScrotoffen ku VoluinproKent Arornaien 26 in the gewonnonöii in Entspannungsvei'dämpfung distillate. ' How Goye below: igt v; ill, working with a can to Grosson Mcsnge of Aromixian 'in the lint schwofe-Itojgsreaktion for "SchwofelcntKUg as harmful leg like tlaö work with to v; onig Aromaton.

The dashed "J th lines in pi /;. 4 cntöpreclmn 'aiiior cuideren jrjögliclion distribution of saturated tone and aroi ^ s ti solion Kolin.enwanserstoffen in the case of the Entüpanmiligrivordn.mpi'ün ^ gcv / omrenen distillate; in dioBom FaJlo b ^ ipnnön the species> r; aien

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in a distillate fraction has an initial boiling point of 288 ° C to outweigh. Since, however, at an output temperature of 288 C all lighter "components pass into the distillate, the saturated hydrocarbons still outweigh the aromatics in amount in the total distillate.

A certain amount of liquid which is driven off by relaxation, evaporation, is withdrawn through line 92 (Pig. 1). Depending on the type of starting material and the conditions used in the desulfurization reaction, the material driven off through line 92 can be, for example, about 5 to 60 percent by weight of the liquid effluent from desulfurization reactor 60; preferably this material is about 10 to 3b percent by weight of the effluent from this first desulfurization reactor. Suitable output star temperatures are ζ.Β »between», about 260 and 427 ° C, preferably between about 316 and 371 ° G. (These temperatures relate to atrnospheric pressure and of course change depending on the process pressure) Both process stages is 34-3 C. The most advantageous amount of liquid that is driven off in this way from the course of the first desulphurisation stage or separated off in some other way can easily be determined by experiments. The distillate that is driven off is fed through duct 92 to a high-pressure Sehnelldeötillation's plant 94, in which hydrogen, hydrogen sulfide and light hydrocarbon gases are separated from a liquid hydrocarbon fraction. The gases are withdrawn through line 96 and purified and separated in the recycle gas recovery unit 97, during which they go through several scrubbing processes and the like What is released from light gaseous hydrocarbons is recovered from the system 97 and circulated through line 99 via the recycle gas compressor 101 through line 103 for reuse in the process

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withdrawn through line 98.

The residue fraction of the flash evaporation plant 90 withdraws through line 100 and becomes with make-up hydrogen mixed, passing through line 102, valve 105 and line 10? is fed. Furthermore, circulating hydrogen can be fed into the make-up hydrogen line 107 from line 103 through line 109, valve 11.5 and line 112 have been introduced. Possibly can supplement hydrogen by means of suitable (not shown) valves directly from line 105 in the line 108 are transferred. The combined stream can be fed to furnace 106 for heating there, if necessary This is desirable internally. Oven 106, however, is not essential necessary, since the current 104 is already on the for the Feed through line 108 to the second desulfurization reactor 110 required desulfurization temperature can.

Temperatures and pressures in reactor 1.10 can be the same as in reactor 60. It is also possible in the reactor 110 use a catalyst of the same composition as in reactor 60. It should be noted here, however, that the desulfurization catalyst is even more active in removing nickel and vanadium than it is in removing sulfur. Most these metals are already in the oil in the first desulphurisation reactor 60 withdrawn. The strongest separation of these metals occurs at the inlet of the reactor 60. At * the second desulfurization reactor 110 only needs to extract the last of these metals from the oil, and therefore separates on the catalyst in this reactor not such a big one Amount of metals from as on the catalyst in reactor 60. Therefore, the catalyst removes the first process stage dam Oil most of the metals and loses much faster in activity alο the catalyst in the second stage.

The entöchv / cfelte effluent from the reactor 110 through line 114 into the atröjwt Schnolldestillationsanlage 116, v, ^r o are aborted light gases, such as VJasserstoff, hydrogen sulfide and light hydrocarbons. Diener Gaastrοία reaches the Hochäruck-Sclmclldcstillu-

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■ fcion system 94 »Sine JLückstan & s £ rakt ± o: i3. _s the erxindungsgemäss herges fcellten-asphalt-containing product in tr ©: contains DER Bestillierkoiönne 122 is zugeführi through line 120 ;. A sulfur-containing stream of "acid" gas and "acid" water is converted from the distillation column 122 through line 124

. withdrawn .. This stream arrives (in a manner not shown) in a gas treatment plant, - where the 'sulfur' is extracted from it. A heavy gasoline fraction is withdrawn from the distillation column 122 by Tieihüig, 152. This benzine can be used as a washing liquid for alatremies of the light Eohlenv / ass materials from the hydrogen conveyed through line 96 (in a manner not shown). will. A fuel oil fraction, or ¹ a 'heavier Eraktion can be removed through line 133 and in the below "are used as described, in order for the sulfurization Int ealctor sr 110 of the second" process step v / urther Aroraaten to overall. win. A product stream flows out of the distillation column 122 through line 134 ah * This desulphurized oil contains asphaltenes and resins and is, without further ado, particularly valuable as a fuel oil, because it contains less than 1 percent by weight of sulfur. This heavy, asphaltic hot oil contains '' e.g. Bi ettfa Oj. 3 to 0.5 weight percent sulfur or less and thus meets the strictest requirements, which are made by ordinances on the sulfur content of heavy heating oils. ·.

The method of discovery provides a yield of products with higher boiling points than the onset of boiling of the thorn first dechulphurous reactors yielded notified goods of not less than 40 or. 50 and up to 80 or 90 percent by weight. In the process there is hardly any hydrogenative cleavage and the hydrogen consumption is generally low in] range from only 2.67 to 26.7 and preferably in the range from 5.34 to 17.8 jim per 100 1 outputs good. The loading of the Entöcl-iwefeiungsroalctörs can not start boiling less than 191 C and preferably has an initial boiling point of. at least 327 or 343 ° G.

BAD mQiJYAk

3 09 8 24/1: 0 8 7.

Therefore, the content is not less of components having boiling points below 191 ° C, 327 ° C or 343 ° C to the product of the second stage hydrodesulphurisation more al s 50 or 60 weight percent, generally, or preferably even only 10 or 20 weight percent. In the process according to the invention, a starting material with an onset of boiling above 343 ° C., for example a vacuum distillation residue with an onset of boiling in the range from 399 to 482 ° C. or more, can be used. In this case, the proportion of the constituents boiling below 343 ° C. in the product of the second stage of the hydrogenative desulphurization is not more than 10 or 20 percent by weight. Accordingly, the method according to the invention can be referred to as an "essentially cleavage-free method".

The fuel oil product of every desulphurisation plant has a total content of asphaltenes and resins of at least 10 or 20, possibly from 30 or 40 up to 30 weight percent the amount that is contained in the feed to the first desulphurisation system. The heating oil product the second desulfurization plant has a preferred total content of resins and asphaltenes of at least 40 to 50 or 70 to 90 percent by weight of that amount in the feed to the second desulfurization zone is included. This is another sign that the resins are and especially the Acphaltene can be desulfurized without they will be completely destroyed, as was the case earlier.

A modification of the method explained by FIG. 1 is shown in Fig. 5 in the form of a simplified flow diagram shown.

. A bottled crude oil is fed through line 220 to a still 222 operating at atmospheric pressure, on? which is drawn off through line 224 a light, asphalt-free distillate fraction with a boiling end of 332 to 343 ° C. and through line 226 a heavy, aaphalt-containing fraction boiling above 332 to 34 3 C with a sulfur content of A percent by weight, Diο acpbalthalti ^ c Riiekijtanrln «Fraction flows through line ?? G to a

- 20 -

BAD ORtG) NAt

30982W10 8 7

at'. ¹ age; 228, from which further light oil is drawn off through line 230. This light oil is passed in a mixture with the lighter fraction withdrawn through line 224 and with the hydrogen fed in from line 235 via line 234- into the desulfurization zone 232. Zone 232 can work with a conventional gas oil desulfurization catalyst at a temperature of, for example, about 204 to 427 ° 0, but at a lower hydrogen pressure (e.g. below 70 kg / cm) than is used for desulfurization of an asphaltic oil. The asphalt-free distillab can easily be completely desulfurized in the gone 232 and is fed through line 236 to the distillation plant 238, from which an overhead fraction consisting of hydrogen, hydrogen sulfide and light gases is withdrawn through line 240 and, as described above, hydrogen for the production and light hydrocarbons is processed.

A fraction rich in aromatics, containing fuel oil and higher-boiling constituents, is removed from the distillation unit 238 through line 244. An asphalt-containing oil flows from ^{1 of} the vacuum distillation plant 228 through line 246, which e.g. has an initial boiling point of about 538 ° C and can contain about 5 »S percent by weight of sulfur. This oil is passed from ■ line 246 through a mixing zone 250 in which the asphalt-containing oil is mixed with a controlled portion of the aromatic-rich fraction withdrawn through line 244 in order to dissolve the asphaltenes and resins contained in the oil and to add the oil to the to bring the desired viscosity. Hydrogen is then fed in through line 248. The heaviest product from the distillation plant 238 can optionally be mixed with the product withdrawn through line ": 268".

• The dissolved resins and asphaltenes contain- • holding asphaltic fraction passes through line 252 in a first desulfurization cone 254 »· where they-under the for the Reactor 60 of the -Fig, .1 "beKoliri flat" conditions cntnchv / o.tolt will. The drain from zone 254 has a 'reduced Schwofelgohalt and flows through line 256 to the between the two casing caiaatufon located 258, a \ u; the hydrogen,

309824/1087

light hydrocarbon gases and a controlled amount « aromatic and saturated hydrocarbons duiriSh; 260 is deducted. Here, as mentioned above, the drives temperature chosen so that the feed for the second zone of the hydrogenated desulphurisation Lich make the asphaltenes and resins the most favorable content aromatic solvent has'. From the flash evaporation system A drain is withdrawn from 258 through line 262 and mixed with hydrogen supplied through line 2f4 will. This rait hydrogen mixed oil stream arrives in a second desulfurization system 266, in which the sulfur content of the asphaltic oil is reduced below 1 percent by weight v / iid. From the second desulfurization attack 266, the works in the same way as the plant 110 in Fig. 1, the heavy oil product is withdrawn through line 26Θ and then, as described above, for the separation of hydrogen sulfide, light gases and the like worked up.

Like Pig. 5 shows one of this procedure works hei with a parallel management by an initially separated from the crude oil lighter fraction is entechwefelt and used to impart the required for the desulfurization Viecoaltät and erforderliehe Lösevermögeri to the heavy asphaltic portion of the crude oil.

Another modification of the by Pig. The method explained in FIG. 1 is shown in FIG. According to Fig. 6 is an asphal Table oil is fed through line 320 to the still 322, where it is converted into a low-aromatic fraction which is passed through line 324 is withdrawn, and an aroiaate-rich fraction which contains $ 4 sulfur. A rich aroma Asphaltic oil is drawn from still 322 by conduit 326 deducted. The distillation system 322 can z.J3. operated like that that an asphaltic fraction with a Sieclebegimi of about 343 ° C is obtained from it.

The asphaltic oil withdrawn through line 326 becomes With what was checked, fed to it by Leitimg 328 is, and the mixture passes through line 330 in a L'n-fc- · cchwefcltmgoanlaco 332, which is described in the above oncn \ .o: i se

- 22 - _BA D ORIGINAL

309824/1087

The ' discharge from zone 332 flows through line 334 into a Hoehdruek expansion evaporation system 336, from which, for example, the proportions boiling below 427 ° G are discharged through line 338, while asphaltic oil boiling above 427 ° G is discharged Line 340 withdrawn.

From Pig. 4 "It can be seen that at a stripping temperature of 427 ° C., a relatively high ratio of aromatic to saturated hydrocarbons. The total tariff salary but the oil is lower at this output temperature than is desired. Hence, in that through ,. Line 340 oil flowing through line 342 is a controlled Introduced amount of an aromatic-rich fraction in order to bring about the dissolution process required for the resins and asphaltenes. The combined stream is then mixed with hydrogen supplied through line 344 and elongated into the desulfurization reactor 346, where the sulfur content of the asphaltic heating oil is reduced to less than 1 percent by weight will. . "-." - "" ·. ·

The effluent from zone 346 flows in via line 348 the distillation plant 350, from which an aromatic series fraction withdrawn through line 352- »A controlled iDeil. this fraction withdrawn through line 352 is passed through line circulated and piped with the asphaltic oil 340 mixed as described above. From the still 350 draw the light gases through line 354 while a practically sulfur-free, asphaltic, heavy fuel oil is obtained through line 356. Practically all asphaltenes and resins fed to still 350, "" are in line 356 together with the asphalt-containing ice ™, oil ßcwomion. The circuit current in line 342 is free of asphaltenes. The asphaltenes do not become the first 3- / ritschv / ef-elungni; o2ie are circulated because they have the Would deactivate the catalyst prematurely. You also will be iric-bt to the second desulfurization zone in the circuit go- " leads because they have already been resolved and eimo / J ο Ιο he circle ".! on fühinmg! pure Sv; eck would have.

- 23 30982-4 / 108?

In the on hand of Pig. 6 explained manner is obtained from the product stream a light, desulphurised, aromatic ^ rich solvent for the asphaltic material,

A further modification of the invention is shown in FIG. shown. Here the asphaltic exit is well fed through line 420 to a distillation plant 422 - around the Av J-gangue and produce a feed to pass through line 426 to hydrodesulfurization is fed. The asphaltic fraction is managed by management

426 is withdrawn from the still 422 and mixed with a controlled amount of an aromatic-rich oil which is supplied through line 428. The oil in line 428 can be a range from about 204 to 566 ° G, preferably from about 343 to 482 ° C., boiling, aromatic-rich fraction. Hydrogen is then mixed with the oil mixture, which is fed in through line 430 , and a stream boiling above about 343 0, which contains about 4 percent by weight of sulfur, is introduced through line 432 into zone 434 for hydrogenating Entoohwefeiung. This plant can at 366 to 421 or

427 C operated v / earth. An expiry with a cowardly cowardice of about 1 percent by weight is fed through line 436 to the birvepension evaporation plant 430 · The plant 438 becomes a fraction consisting of light oil and gas which practically contains all of the hydrogen sulphide produced, stripped off and withdrawn through line 440. This ötroro can E.g. have an end boiling point of 343 0.

An oil that boils above 343 ° C, for example, is mixed with hydrogen, which is fed in through line 442, and through line 414 into a wide sulphurisation zone 446 which is also extet at 366 to 4 21 or 427 ° C The process also do: c second desulfurization zone 446 has a sulfur content of less than 1 f> and. v / is fed through line 448 to the decolorizing system 4 50. The def5i; i: il: i craning system 450 is o : mc aephaltene-free, aromatic fraction drawn off through line 402 and taken through line 428 for mixing with the aLiplviltisclieii Ölbeßchickiing for the erijte Entncliv / efelunguaoii © 434 in

- 24 30982 kl 1 087

. BATH ORIGINAL

Cycle guided. The distillation unit 450 turns hydrogen sulfide and light gases withdrawn through line 454, while a low sulfur asphaltic fuel oil through line 456 is removed. The portion of the oil in line 452 that is not in the. Circulation can be carried out with the product in the Line 456 are mixed in order to reduce its sulfur content.

The one in Pig. The arrangement shown in FIG. 7 thus makes use of a low-sulfur, aromatic-rich product stream _{T in} order to make the asphaltenes and resins soluble in a heavy starting material for desulfurization with a relatively high initial boiling point.

An amendment made by Pig. The system illustrated is in Pig. 8 shown.

The method according to Pig. 8 is similar to that according to Pig. 7; in Pig. 8, however, that withdrawn through line 440 from the flash evaporator 438 is withdrawn Process of a relaxation drying system equipped with cooling coils 441 supplied. Hydrogen sulfide and light gases are withdrawn through line 443. The rest Heavier effluent is withdrawn from the flash evaporation system 441 through line 445 and through the pump 447 after mixing with the oil. fed from line 444 to the second desulphurisation plant 446.

The working method according to Pig. 8 enables the Spannurigsverdampfungsanlage 438 at the same temperature can be operated like the desulphurisation systems 434 and 446. At the same time, the decompression system equipped with cooling coils and working at a lower temperature enables 441 the separation of hydrogen sulphide and light gases and the reintroduction of its oil with the most favorable aromatic content and start of boiling.

If e.g. 'Ji. it is found that the most favorable output temperature zwi see the two process steps corresponds to a value of 343 0 at atmospheric pressure, and if the Lnir.chv / ol'e.lnngf.sanlagen 434 and 446 work at 371 ° C diait-cjjjellationa-pre-vaccination plant 438 also at 371 ° C

- 25 ~
309824/1087

work. Then, however, the flash evaporation system 441 operated at the lower temperature works at 345 ° C and thereby enables the return of the temperatures above 343 ° C boiling parts through line 449 "

Therefore, in the embodiment according to FIG. 8, it is not necessary to reduce the temperature of the oil in line 436 and reheat the oil supplied through line 444.

According to FIG. 9, an asphaltic, sulfur-containing hydrocarbon oil is fed through line 520 of the distillation unit fed, v / o this oil is broken down into light gases, which are drawn off through a line, and an aroma-rich fraction withdrawn through line 526 and used in the manner described below. The aromatic fraction can have an initial boiling point of 343 0.

An asphaltic residue fraction with an initial boiling point for example about 343 ° C is through line 528 withdrawn and mixed with hydrogen supplied from line 530 prior to introduction into the first desulfurization zone 532. The desulfurized effluent from zone 532 is transferred through line 534 to the flash evaporator 536. As described above, the most favorable output temperature is beforehand been determined, and a light oil fraction that is saturated and aromatic- containing hydrocarbons together driven off with light gases and hydrogen sulfide and withdrawn through line 530. ;

The asphaltic oil is withdrawn from the despamming evaporation system 536, mixed with hydrogen from line 540 and fed through line 542 to the second defoliation zone 546. In addition, the asphaltic Ber.ehik- · -. kung. for zone 546 still mixed with the aroinate-rich oil fed in through line 526. The distillation process in the system 522 is carried out under conditions such that ^c J (las oil in line 526 de "for the maximum DoI - vatisicrung flor in the feed of the ZV: oitan EntscUiwcfeliingfl · '' / ■ one 54 6 Asphaltono contained the most favorable ftioflcburoii.ch and Aronatengohiilt. At the end of a zone ^l j- ^f \ (> tangled through line 5-Ή; dor Do. '; Li: i lic:!.': πQ. ;; ■ ^ e 5! K) i. '/ Ugoführ I, iiu ..: del

- 26 30982W 1087- BAD OR ₁ GINAL

the asphalt-containing heating oil separated in it through. management flows off. Light gas is withdrawn through line 554 and commercial spirit through line 556 and treated in the usual manner.

example 1

An asphalt-containing, topped crude oil with a sulfur content of 4.09 percent by weight is passed together with hydrogen into a desulfurization zone in which a nickel-cobalt-molybdenum catalyst is located on an aluminum oxide carrier without cracking activity. The hydrogenating desulfurization takes place at temperatures of 343 to 438 ° G and a ¹

Hydrogen partial pressure of 140 kg / cm, and the resulting asphaltic product is made at a temperature equal to atmospheric pressure corresponds to a temperature of 343 C, the flash evaporation subjected to a drain with the most favorable content of aromatic and saturated hydrocarbons to obtain. The asphaltic asphalt that was withdrawn from the flash evaporation system and boiling above 343 C. Fraction has a sulfur content of 1.09 percent by weight. And! is fed to a second desulphurisation zone, where the desulphurisation also in the temperature range from 343 to 438 Ω on a catalyst of the same composition as in first stage is carried out.

A heavy fuel oil with a sulfur content is obtained of 0.58 percent by weight. The sulfur distribution in the "different Fractions of the oil subjected to desulfurization are shown in Table I.

- 27 309824/1087

O) ω cr> Ln in Fi cn VO in CTi ω kn • Ρ sphal

kn

ω U

tr-

VO

lf \

VD

o · cvj

CvJ o-

<! VJ

VO

in

Fi in ■ ν} ' in ω O «D- -P in in O R. U.N. VD O Fh

VD

VD

in O

(U

G) P -P co

W) fl • rl Cl -ι- " ¹ ω -P»

: ci rf

W ;;

0) Fl

ti> 0)

^r 1

CO CvJ

t - KN

CM

CM CM

ω ο

vh KN

CM CM

F! CO Γ CD I. 0) Q) Fi 1 .,, -P • Fi \ *> G) c; j n1 -1-5 rj G) . .p 0) I. -P O | -; • rl O '.-- ι-1 J-J cn <d * 10 Ki 'J ϊ -I ' fi J 0) ti CJ Cj J: 'L-! C ' Fi ί ¹ - ' C's r-l t.'i ω c!>, '. { 0) (1 C) ICi c-j UO O c> f-l «. rl 11 I, _r c "! t. Jm ·. I?) P 4 F "! Cii £ | ■ j ^r o 5-! F-H ^r i Fl rl r-l O '-! * C) rl c> i-D C) co H C) O V, :O •H 'ο fi 'Ii C-i • r-l rl ■ rl 'C) O • rl Ί I O I ^ -) ■ "· IJ) C) Cj ■ P O • P ^c .-! -P ft) ■ rl • ι ί 1 -f r-l ■ (Ί W) ί ■, L J Cj-; I '
r '' i W. P) IJ »-» -I ³ CD V .; o> -P 'd' C) (J C-) " to, <■; ( J
r I Fl «Ι-1 Γι f_. F ι ο P.! (■ 1 C!) c-j I, - ' 'O ί 'I l '! I t Cj In the IO Fi * .-; F-l Ό 10 Ό O ti Vh _r <: i I ι • Η -J * ' IO ■ i-l • P C) . £ "! F-i / ■! rl - 28 r / j ! ■! 3 0 O 4 / ^; ί 0 10 co ge ο 0) η PI

From Table I it can be seen that the sulfur in an asphaltic starting material which has a total sulfur content of Has 4.09 percent by weight, relatively globally, based on saturated hydrocarbons. Aromatics, resins and asphaltenes is distributed. But if the starting material has been through the first desulfurization sz one passed and the fraction with "an end boiling point of 343 ° C with a total sulfur content of 1.09 percent by weight is driven off, the saturated and aromatic hydrocarbons have their sulfur content greeted part lost, i.e. * they only contain 0.80 or 1.12 percent by weight sulfur, while the resins and asphaltenes only have a sulfur content of 2.37 and 4.95 percent by weight, respectively have been desulphurized, so much less sulfur has been removed from them. After the second desulfurization stage Significant percentages of sulfur remain only in the resins and asphaltenes.

It can also be seen from Table I that the aromatic content of the starting material after rapid evaporation after the first process stage has risen from 55.45 percent by weight to 60.45 percent by weight and finally in the product to 61.91 percent by weight. At the same time, the weight ratio of aromatics to the sum of resins and asphaltones increases from about Z-. 1 to about 4: 1. Table I therefore shows that it is of crucial importance to ensure that the asphaltic oil contains enough aromatics so that the resins and asphaltenes remain in solution and any asphaltene aggregates that have already formed are dissolved again and thus accessible for desulfurization v / earth. Furthermore, the table shows, claus es essentially int, the presence of a :: tjborsohussers of liquid which contains aromatics and especially saturated: if.tc] iQ} jlonv.'aüfjü: i-fjtofi'e, over "that amount up ;, . the '/ Aw Löslriohrnachen eggs resins and .Asphaitone is necessary to avoid, as a solcher- surplus .an sulfur · -. ai-III rock liquid no other Y / MPACT when the scliwöfel- hiüAj ^ cn] i !; To disperse and dilute rzo and asphalt De and thereby reduce the Y / ahraoheixiIiohl-Git iliros' meeting ii: it ck: /:] catalyst. Furthermore, it should be noted that-

3O9S24 _rt / i0S7 BAD ORJGJNAL

the aromatic content of the feed to the second process stage is higher (60.45 percent by weight) than that of the feed to the first process stage (55.45 percent by weight). This is partly due to the expansion evaporation carried out between the process stages up to a stripping temperature of 'M-3 ° C, where a relatively larger proportion of saturated hydrocarbons is transferred to the driven off light oil troia than to aromatics. In each process stage, the weight ratio of aromatics to the sum of Hari.en and Asphalteneqn for the purpose of dissolving the latter should be at least 1: 1 and preferably 1.5 oc'.or 2: 1 and can even be 4 or 5: 1. The aromatics can already be contained in the starting material, they can be added by recycling, or they can be generated on site by reaction.

It can also be seen from Table I that the saturated hydrocarbons driven off are the ones that desulphurized the most Fraction are, and therefore have the least need, passed through the second process stage dor desulfurization will.

The following example explains the resistance of an asphalt:!. See starting material against sulfur deprivation, if wan tries to reduce the Schwofelgchalt below $ 1 without from make use of the method according to the invention.

A to 22 <fi a'bgetoppteis Kuwait crude oil, which contains an asphalt fraction and ^c j, A''j weight percent sulfur, dor is subjected to desulfurization. The öiedebeginn of Hohölö is edohereich at 291 ° C and dor HA extends to above YGO ⁰ 0. After 'IIcrabwctzung dos Bchwofolgehaltcs to 4.77 percent by weight of the Siecicboglmi at 268 ° C, and, Siodobcro: i c am-jl ranges above 760 ° C.

If one continues with the desulfurization and the f'chv.'cf (! L ;; eho.lt to 1. -11 percent by weight is eggs Siecjcbcjinn 265 ° C, and the oieclobereieh expanded. olcl) bifj ' ol) t; rlialb 760 ° C. But if the lie] iwe.l'o: content ituf 0, B; 3 Gc

- 30 -

BATH ORIGINAL

3 Ü 8 8 2 L ι ι üii 7 '■ - ■■ "■":

weight percent is reduced, the onset of boiling drops from its initial value by 50 °. C to 241 C, and the boiling range extends to over 760 C _e

i? Results of this experiment are shown in Table II.

Table II

Starting

good sulphurisation

Sulfur content,

'Weight -5 pounds 5.43 4.77 1.41-0.83

Boiling range, ⁰ O 297-760 + 268-760 + 265-760 + 241-760 + desulfurization, '#' - 12.2 74.0 85.0 Specific

Weight, 1.0254 1.0093 0.94-84 0.9321

The above values show that the sulfur contained in the starting material becomes very resistant to further desulfurization after about 74 percent desulfurization. With a desulphurisation of 12 fo the start of boiling is reduced to 268 C, while with a desulphurisation of 74 fi the start of boiling is only reduced to 265 C. But if you want to achieve 85 percent desulphurization, the start of boiling drops to 241 ° C. In the one-step procedure, with more than 74 percent desulphurisation, the hydrogenative cleavage begins to outweigh the hydrogenative desulphurisation, i.e. carbon-carbon bonds take place Kohl ens toff-Schvef elbiiidiingen split up.

Table III shows the composition of the Gutss during the desulphurisation reaction.

- 31
BATH ORIGINAL

30 9 8 24; / 1 0.8 7

Table III

Change in composition of starting material, during desulfurization, Gcw.- |> Weight- ^

Desulfurization,

12.2

85

Saturated coals
hydrogen 11 16.7 ^: 26.1 33.2 Aromatics 39 41.2 56.6 49.9 Resins 32 25.7 15.1 15.3 Asphaltenes 18th 16.4 2.2 1.6

From this it can be seen that with increasing deficiency the amount of resins and asphaltenes decreases as they are converted into saturated and aromatic hydrocarbons will.

Table IV provides a comparison of the aromatic, saturated hydrocarbon and residue molecular weights scoraponents in desulfurization.

Table IV

Mole ku 1 ar weight. ts an el er υ η g at the ICnts c. hwcfe 1 uη <\

Dilation, 5 »

Saturated coal w a κs er s t o fie, Mo 1 e kul arg e v; i c Ii t

Aromatics,

l'ü oils gularly weighted

G es aw tr üc k π t and y ~ k ο JTi j) ο nc η ten, H ο 1 c 1; ιχ 1 ar gew i e Ir I;

1080

12.2

430.0
4 90.0

590.0

400
530

490

85

410 400

420

Table ^Ιλ Γ ^ isplays, dans with zimehmendcm Entschwofolungr; abniinint dor Rüekstandökoraponenton -grad dac molecular weight, but not wogentlieh becomes lower than the molecular weight of the sieve au initial forming saturated and aromatic hydrocarbon / env materials ater. This molecular weight distribution shows that the breakdown of carbon-metal bonds in the hard and asphaltic hydrogen fractures is involved; c -; - nt- ■ stand approximately in the same l'iolelmlargev / ichtnbcrcicli Hc--

BATH ORIGINAL

0 9 8 2 4/1087

genes like the saturated and aromatic ones contained in the starting material Hydrocarbons.

Example 3

About the influence of the dilution and concentration of the resins and asphaltenes in the feed to the second process stage To explain the desulfurization rate in the second process stage, one works with one Abtrisbstomperatur of 343 ° C with a starting material that "already go through a one-step desulphurisation process Has. The asphaltic asphalt that remains behind in the case of rapid evaporation In a second process stage, the residue is subject to hydrogenation desulfurization, whereby a Desulfurization reaction rate constant of gives about 85. The desulfurization reaction rate constant is calculated in the usual manner according to the following j? orriiel "calculates: '

kg oil kg oil

kg sulfur h «kg catalyst

This reaction rate constant can also be given by the equation • \ -

k = ( i - i] HiSV

expressed v / earth, in which Sp kg sulfur per kg oil in the product, Sj ₁ . kg sulfur per kg oil in the starting material and LHSY space parts oil per hour per space part catalyst.

For comparison purposes, the residue at 343 ° carried out flash evaporation a desulphurized Heating oil with a boiling range of 204 to 343 ° 0 and a Schwofel content of 0.07 percent by weight was added. This Heating oil consists of about half of saturated hydrocarbons and half of aromatics. If you have this asphaltic Output material through a second desulfurization stage conducts, the reaction rate constant of the desulfurization decreases down to 75. Due to the excessive dilution of the Feeding the second process stage is therefore the reaction rate the desulphurisation reduced, even when aromatics are added.

- 33 -

30 93 247 108?

In a further comparative experiment, the lowest-boiling 30 percent by weight of the charge to the second desulphurisation stage is driven off, so that the charge now corresponds to the residue from an expansion evaporation carried out at 427.degree. In this case, the reaction rate constant of the desulfurization II of the first process stage drops to 40, which is due to the inadequate solubilization of the resins and asphaltenes. This clearly shows that the amount of saturated and aromatic hydrocarbons! which are introduced into the second process stage together with the resins and asphaltenes, have a significant effect on the reaction rate in this process stage, and that too large an amount of diluent has an equally detrimental effect on the reaction rate of the resolution. may have ^r efeiung as a too small amount of aromatischem- solvent.

In order to determine the influence of sufficient, as opposed to excessive, solubility of an asphalt-containing raw material, a high-boiling residual oil with an initial boiling point of ^x 427 ° C is desulphurized by 76.2 percent by weight by hydrogenation. A second sample of the same raw material is first diluted with 30 percent by volume of a lower-boiling gas oil, which has previously been degreased by 90 to 95 percent by weight. By adding the gas oil, which »has a high aromatic content, the degree of desulphurisation is increased to 80.3 percent by weight.

Another sample of the ·. AungangfigutoD pre-diluted with 40 percent by volume gas oil and, as above, subjected to hydrated desulphurisation. In this Pa.ile the Entschv / efelungiiaktivität, and EntscJiwofolvin / ¹ yinkt; "- degree drops to 76.3 percent by weight. If you add 64 percent by volume of cast oil, the degree of desulfurization drops by ν / α: 1-tcr to 69.4 percent by weight. The ErgcToiiuue d: u; f; er bookings;

- 34 · -

9 8 2 4/1087 ' ^BA0

are compiled in Table V.

lab rush 'V
~ ' Influence of dilution with gas oil

Gas oil, vol .- ^ S 0 30 _s 0 40.0 64.0

Degree of defilement,

Wt .- / * '■ 76.2 80.3 76.3 69.4

Removal of vanadium,

Wt .- / »83.5 78.6 74.6 77.8

The above words show that you can through thinning an asphaltic oil with gas oil at the beginning with the hydrogenating Desulfurization as a result of the dissolving power of the aromatics contained in the gas oil for the resins and asphalt cne Gain advantage. However, this advantage can be achieved by a large amounts of diluent are overcompensated, because the thinning agent is then primarily used as a dispersant acts for the sulfur-containing molecules and thereby reduces the reaction speed of the desulfurization «. An excessive amount of diluent can also have a detrimental effect on the desulfurization, that it causes too high a throughput rate in the desulfurization reactor »

-Example 5

An experiment is carried out in the first and the second process stage a nickel -'-IvObalt-molybdenum catalyst with a carrier made of aluminum oxide with particle, diameter)! 0.79 mm is used. In the first stage has the catalyst in the desulfurization of a topped Kuwait crude oil from a sulfur content of 4 percent by weight at least one of 1 percent by weight at an hourly rate Fluid flow rate of 0.8, an initial temperature (temperature at the beginning of the experiment) of 366 C and a final temperature (temperature at the end of the "experiment) from 421 C a service life of 6 months. The second stage is the life of the catalytic converter even longer. From the 1 percent by weight of sulfur

OHigi _Nal 3 0 9 8 iÜ i'Qfi-7 " ¹

stage Tenden expiry of the first procedure durcj ^"1 Entsparnungsverdampfung the fraction with a final boiling point (relative to atmospheric pressure) of 343 ° C stripped, and the residue is desulphurized together with hydrogen, in the second Verfahrensijtufe a Schwefelgenalt of 0.5 weight percent. The initial temperature in the two-tone stage of the process is 366 ° C. and the temperature after 170 days is 406 ° C. The experiment can be continued until the temperature has reached 21 ° C. In this way, the first and second process stages can be carried out in the method according to the invention 3j 4, 5, 6 or even 7, 8 or even 12 months at an hourly liquid deposition rate on volume levels of 0.1 to 10 or preferably 0.3 to 1.25 work Catalyst is longer in the second process stage than in the first process stage.

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Claims (17)

Gulf Research & Development
Company Patent claims Process for the production of asplial thai tiger ileizöl, characterized in that a sulphurous asphaltic hydrocarbon oil is passed together with hydrogen through a first zone of hydrogenation desulphurisation, from the first zone of hydrogenation desulphurisation a light gas fraction containing hydrogen sulphide, a saturated and aromatic hydrocarbons containing light oil fraction and a high-boiling asphaltic fraction "consisting of the first discharge with reduced sulfur content, separates the light gas fraction and part of the light oil fraction from this discharge, the remainder of the first discharge consisting of the asphaltic fraction and part of the light oil fraction passes together with hydrogen through a second zone of hydrodesulphurisation, each of the two zones of hydrodesulphurisation containing a catalyst with a carrier without cracking activity, and from the second zone the hy drierenden desulfurization withdrawing a second outlet in the form of a low-sulfur fuel oil ub ~ phaltischen. 2. The method according to claim 1, characterized in that one.al "carrier without cleavage activity" uses such, which consists essentially of aluminum oxide » 3. Ancestors according to claim 1 or 2, characterized in that that by separating the Loichtöl fraction from the first Drain increased the aromatics content of the remainder of the first drain. 37 - 3098247 4. The method according to claim 1, characterized in that one works under such conditions that the second sequence at least 20% by weight of the asphaltic material fed to the first hydrodesulphurisation zone Hydrocarbon oil contains asphaltenes and resins. 5. The method according to claim 4, characterized in that one works under such conditions that the second sequence at least about 20 to 80 percent by weight of the asphaltenes una contains resins) the asphaltic materials supplied as starting material in the first zone of the hydrogenating desulphurisation Hydrocarbon oil are included. 6. The method according to claim 1, characterized in that one works under such conditions that not more than 60 percent by weight of the second run has a boiling point below the beginning of the boiling point of the asphaltic hydrocarbon fed as starting material to the first zone of the hydrogenative desulfurization Have oil. 7. The method according to claim 1, characterized in that one works under such conditions that no longer alo 20 percent by weight of the second run a boiling point below 343 C. 8. The method according to claim 1, characterized in that one the light gas fraction and said part of the light oil fraction by relaxation evaporation from the first process separates. 9. The method according to claim 8, characterized in that man · from the first sequence! 3 am 00 percent by weight as part the light oil fraction drives off. 10. The method according to claim 9, characterized in that from the first run about 10 to 35 percent by weight as Part of the light oil fraction drives off. - 38 - 3 0 9 8 2 l- ■ TCB 11. The method according to claim 8, characterized in that one carries out the Eratspannungrr / erdarnisierung hei Tempora door on, the temperatures measured at atrnospheric pressure of otwa 260 to 4-27 ° C. 12. The method according to claim 11, characterized in that the relaxation is carried out at temperatures the hot atm ο spherical pressure measured temperatures of about 316 to 371 ° C. 13. The method according to claim 8, characterized in that by stripping off the light gas fraction and part of the light oil fraction from the first drain, the aromatics content the first sequence to solvate the contained therein Resins and asphaltenes increased from the second zone of hydrogenation Desulfurization withdraws a second effluent that is at least 20 percent by weight of that in the first zone of the hydrogenating Desulphurization asphaltic feed as raw material. Asphaltenes and resins contained in hydrocarbon oil contains, this second flow is fed to a distillation zone and from the latter an asphaltic heavy oil of reduced Sulfur content wins-. 14. The method according to claim 13, characterized in that the stripping is carried out under such conditions that about 10 to 26 percent by weight of the lower boiling point of the first run Components are separated. 15 · The method inch claim 1 to 14, characterized in that one in two zones of hydrodesulfurization mii a nickel-cobalt-molybdenum catalyst supported on alumina works _0th 16. The method according to claim 1 to 15, characterized .gekiert, that one in both zones of the hydrated desulphurisation a hydrogen partial pressure of about 70 to 350 kg / cm works, 17. The method according to claim 13 »characterized in that one works under such conditions that no more than
60 percent by weight of the second run has a boiling point below the initial boiling point, that of the first zone of the hydrogenating
Desulphurisation of the topped crude oil supplied as a starting material on a lot of s en. 3D98 2A / 1U8 7 »Μ Blank page