DE1954004B - Process for the conversion and desulfurization of a hydrocarbon feed - Google Patents

Description

a) The feed is heated to a temperature in the range of 260 to 413 "C.

b) the heated feed in the catalysis reaction zone at a pressure of Reacts more than 6 atmospheres with hydrogen,

c) the resulting P.actic'szone discharge in a first Trer.nzore at about the same pressure as that of the catalytic reaction zone in a first Damplphase and a first separates the liquid phase,

d) the first vapor phase in a second separation zone at approximately the same pressure as in the separates first separation zone and at reduced temperature into a hydrogen-rich second vapor phase and a second liquid phase,

c) at least part of the second vapor phase is returned to the catalylic reaction zone,

f) at least a portion of the first liquid phase in a third separation zone at about the same temperature separates into a third vapor phase and a third liquid phase.

g) at least part of the third liquid phase in a non-catalytic thermal Reaction zone cracks,

h) the resulting cracked product out-Π11 Γί in a fourth Trcnnzonc at a reduced pressure of I ala to 6.8 atm in a fourth liquid phase and a fourth vapor phase separates and

i) the fourth liquid phase in a fifth separation / cmc at a reduced pressure between Under atmospheric pressure and 3.4 atm in an asphaltic residue and at least a fifth liquid phase, the dcstillicrbarc hydrocarbons of reduced do Contains low content, separates.

2. The method according to claim I. characterized in that one part of the fifth liquid Phase in such an amount into the third liquid ds Phase returns that there is a ratio of the combined feed to the thermal Rcaktionszonc of about 1.2: 1 to about 3: 1.

3. The method according to claim I or 2, characterized in that one part of the first liquid! 'hare in such a quantity in the E: nsatzmaierial returns that there is a ratio of the combined feed to the kaialytic Reaction zone from about 1.1: 1 to about 3.v! results.

4. The method according to any one of claims I to 3, characterized in that part of the fifth liquid phase returned to the feedstock for the catalytic reaction zone.

5. The method according to any one of claims 1 to 4, characterized in that mar. the second Maintains separation zone at a temperature in the range from 16 to 60 C.

6. The method according to any one of claims 1 to 5, characterized in that the third separation zone at a pressure in the range of 10.2 to 23.8 atmospheres.

7. The method according to any one of claims 1 to 6, characterized in that the thermal Reaction zone at a pressure in the range of 10.2 to 23.8 atmospheres and a temperature that is approximately coincides with the temperature of the third liquid phase.

The invention relates to a process for converting and desulfurizing a hydrocarbon feedstock, of which at least 10% boil above 566 ° C and the one relatively low Metal content, especially less than about 150 parts per million total metals, calculated in the elemental state, but a high sulfur content, in particular more than 2.0 percent by weight, with the formation of lower-boiling distillable hydrocarbon products reduced sulfur content, at which the hydrocarbon feed after heating in a catalytic reaction zone at elevated pressure in the presence of hydrogen for removal of sulfur compounds and the production of low-boiling Hydrocarbons reacted, the resulting reaction mixture separated and thereby obtained liquid Parts of a further cracking reaction with subsequent work-up of the reaction products be subjected.

Such hydrocarbon cine salt materials, which are usually called black oils because of their usually deep dark to black color, such as crude oil and in particular the heavy residues, crude oils and vacuum residues extracted from tar sands. also contain nitrogenous compounds, asphaltic substances which are insoluble in light hydrocarbons such as pentane and / or heptane, and organonietallic complexes of high molecular weight. The metallic complexes contain nickel and vanadium as metal components. Such a material generally has a specific gravity greater than about 0.9340 at 15.6 "C and a Conradson coke residue of generally 1.0% by weight; a large proportion of the black oils have a C'onradson coke residue above 10%. Examples of black oils of this type are the bottom products from Rohokkstillationskolonncn, 7 .. B. a

954

PiiiJenpiuiliiki mil a specific weight of flua ii. ') 70: "Iu-i I \ 6 C and a content of Vciuiiftiniimngen of about 3. (1 percent by weight Sclmek-1. jK.Sirieile per million corneal nitrogen, is: "I hurry ever IHilliiPii (ies.imtmetalle. About! 1.0 OewiLlitspr ../ eiii ■ "Nlö'-lichc Asphallhene and about 40. (1" "my desiillerhare Anieiie.

i) ie-e. ! and are offered in abundance on the market Low-value input materials or their fcoehmolecular fractions can largely only be used as to fcirahenasphali or - hei dilution with higherized Pesullaic hydrocarbons - as extremely jienriLH '. Finished heating oil can be used. It ordered Suddenly a pronounced technical interest in one smoking whores and economic conversion of the- ■ .-- »Newer black oils in desulphurized lower-boiling ones Coals wasserstolTprodukic.

The main difficulty with the previous processing methods is the lack of sulfur stability of the catalytic converters, if the feed material is large amounts of asphaltic substances and sulfur contains. Because the process with such high operational severity must be carried out that simultaneously with the conversion of sulfur-containing compounds into Hydrogen sulfide and hydrocarbons are converted from non-distillable components, the asphaltic constituents dispersed in the feed material tend to agglomerate and polymerisation so that their conversion into more valuable oil products is practically excluded. Furthermore, the polymerized asphaltic complexes are deposited on the catalyst, which leads to leads to a constant increase in the deactivation rate.

Hydrocracking processes and those involved Reactions are well known (Kirk-Othmer. Encyclopedia of Chemical Technology. 2. Aullage. Vol. 15. 1968, pp. 35 to 37). With this one Process, however, is not generally a hydrocracking process on recycled material to use for their desulfurization, but rather it should be the effluent of the catalytic The reaction zone continues in the presence of considerable amounts of hydrogen, as this inevitably occurs the catalytic reaction zone with enters the next reaction zone, and in connection with certain Separation and return measures are implemented. How this has to be done in detail. cannot be found in the literature. It there is only the hint that a catalytic <o Developed "synthetic" oil then given to a toilet Hydrocracking by one of the methods. as developed for loads obtained by distillation can be subjected. Such hydrocracking also works catalytically; it is this embodiment of the known then a two-stage process with catalytic conversion in both stages. Such a thing However, the method of the invention does not seek to proceed. fio

The reference can also be found in the same literary text. ikAS Hydrocracking reactions with a relatively low risk of catalyst crosslinking can be carried out more slowly and even at 288 "C. However, these are only dc results of laboratory scientific investigations on the lower temperature ranges of the start of the reaction of the reactions of interest; an indication of the Process is called one in mil! When I am not able to win this line of work in industrial processes 11. Accordingly, it is pointed out in the same literature that higher temperatures are used in technical processes

Also the information in the Lileralurslelle. dah iiei hehlen of Metallvei unreiniguncen in the \> destiny a Kataivsatorlebensdauer of lflOTagei. or longer! The fact that high-quality catalysts can be protected from contamination by pretreating the charge with Wasv-Tsioff or by carrying out the hydrocracking in two stages with different catalysts in the two hydrocracking stages do not give any indication of the method of operation according to the rules of the invention.

Thermal cracking processes for the conversion of hydrocarbons; to lower boiling products have long been ^"7 To the art (Gruse and Stevens, Chemical Technology of Pen oleum, 3rd edition, New York, Toronto, London, 1960, p 344). When prescribed by the process of the invention operation However, the material flowing from the catalytic reaction stage to the reaction zone of the further cracking reaction inevitably contains considerable amounts of hydrogen Separation and recycling measures cannot be converted catalytically in a further reaction stage, so that the particular results and advantages aimed for with the process according to the invention can be achieved.

It is therefore the object of the invention to find the highest-boiling, normally non-distillable Components of a black oil feed conversion to more valuable hydrocarbon products, for example gas oil fractions ;;. feed, at the same time a thorough desulphurization Values below 1.0 percent by weight, for example, ensure agglomeration and polymerization of the asphaltic constituents dispersing in such feedstocks, causing a conversion in valuable oil products practically excludes and in connection with the sulfur content to one rapid catalyst deactivation leads to prevent and both the yields of valuable products as well as increasing the possible operating time and the catalyst life.

This object is achieved by a method dei type mentioned at the outset. According to the invention, this is characterized by the fact that one

(i) the input material to a temperature irr

Heated range from 260 to 413 ⁰ C,
(b) the heated feedstock in the catalytic reaction zone at a pressure greater than:

68 atmospheres with hydrogen,
Ic) the resulting reaction zone outflow in a first separation zone at approximately the same Druct as that of the calcium reaction zone in a first vapor phase and a first liquid phase

separates,
(d) the first vapor phase in a second separation zone at about the same pressure as in the first

Separation zone and at reduced temperature into a hydrogen-rich second vapor phase and a second liquid phase separates.

(e) recycling at least a portion of the second vapor phase to the catalytic reaction zone.

(0 at least part of the first liquid phase in a third separation zone at about the same Temperature separates into a third vapor phase and a third liquid phase,

(g) at least a portion of the third liquid phase in a non-catalytic thermal reaction zone cracks,

(h) the resulting cracked product effluent in a fourth separation zone at a reduced rate Pressure of 1 ata to 6.8 atü in a fourth liquid phase and a fourth vapor phase separates and

(i) the fourth liquid phase in a fifth separation zone at a reduced pressure between subatmospheric pressure and 3.4 atmospheres in an asphaltic residue and at least a fifth liquid phase, the distillable hydrocarbons of reduced sulfur content contains, separates.

This creates a process that is simple and economically a very extensive conversion, for example from 70 to 80 percent by volume, such black oils are permitted in largely desulphurized, distillable hydrocarbons, and this with a long service life of the catalyst in the catalytic conversion stage. Due to the special Linking the series connection of catalytic conversion and thermal cracking With specific separation and return measures, a joint process is created at Among other things, the separations almost exclusively through extremely simple phase separations of gaseous and liquid phase carried out in separators that are very simple in terms of operation and costs will.

Preferably at least part of the fifth liquid phase is recycled and with the third liquid phase combined in such an amount that there is a ratio of the combined feed to the thermal reaction zone from about 1.1: 1 to about 4.5: 1, in particular about 1.2: 1 to about 3: 1, " results.

According to a particularly preferred mode of operation, the fifth separation zone consists of a vacuum column, those used to concentrate the unconverted asphaltic residue and to generate it at least one heavy vacuum gas oil, one light vacuum gas oil, and one for reprocessing suitable waxy fraction, hereinafter referred to as "slop wax" fraction, is driven. Preferably the latter (with or without some of the heavy vacuum gas oil) becomes the thermal cracking zone returned. If the desired product distribution so requires or makes it appropriate, can part of the slop wax fraction is returned and with the fresh black oil feed for the fixed bed reaction zone be united.

The total feed to the first fixed bed catalytic hydrogenation zone, including recycled Hydrogen and make-up hydrogen to maintain pressure and replenish the im Total process of hydrogen consumed, is preferably to a temperature in the range of 343 heated to 399 or 413 "C. The temperature to which the feed for the catalytic reaction zone is heated is within the aforesaid By monitoring the temperature of the product outflow from the reaction zone. There the main reactions taking place are exothermic, there is a temperature rise during passage feed and hydrogen through the catalyst bed. One technically and economically Usable catalyst life is achieved when the maximum catalyst temperature, which is practical coincides with the temperature of the product outflow, is maintained no higher than about 427 "C. According to a further preferred feature, the outflow from the first reaction zone enters the first separation zone at a temperature of 37] to 413 C. to ensure that the heavy components of the reaction zone product effluent are not carried into the mainly vapor phase.

As a measure for controlling the temperature in the fixed catalyst bed, in a conventional manner a cooling hydrogen stream or a cooling liquid or both at one or more intermediate points of the catalyst bed are introduced. Preferably, the catalytic reaction zone is under one Piuck held from 68 to 272 atmospheres. The hydrocarbon feed can flow at an hourly space velocity of the liquid from 0.5 to 10.0 based on the fresh hydrocarbon feed exclusively recycled diluting components and / or any for temperature control applied cooling streams, are passed over the catalyst. The hydrogen concentration should conveniently be in the range of about 890 to about 8900 standard m710001. The ratio of pooled feed, defined as the total volumes of liquid feed per volume of fresh hydrocarbon feed, should suitably be in the range from about 1.1: 1 to about 3.5: 1.

The catalyst located in the fixed bed catalytic reaction or conversion zone can are characterized as a material containing a metal component having hydrogenation activity, wherein this component with a suitable high-melting carrier material based on inorganic Oxides of either synthetic or natural origin are combined. The exact composition and the method of preparation of the support material are for the method according to the invention not essential, but it should be noted that a silica-containing carrier, ζ. Β from 88.0 percent by weight of aluminum oxide and 12.0 percent by weight of silicon oxide or from 63.0 percent by weight Aluminum oxide and 37.0 percent by weight silicon dioxide, generally preferred will. Suitable metal components with hydrogenation activity are those based on metals Groups VIb and VIII of the Periodic Table (Periodic Table of the elements according to E. H. Sargent & Company, 1964). So can the catalytic composition one or more metal components au; of the group molybdenum, tungsten, chromium. iron Cobalt. Nickel, platinum, iridium. Osmium. Rhodium ruthenium; and mixtures and compounds of which, included. The concentration of ka, ilytischer Metal component or components depend primarily on the metal selected in the individual case as well as the properties of the input material. Example

wise are the metal components of group VIb generally in an amount in the range from 1.0 to 20.0 percent by weight, and the iron group metals present in an amount ranging from 0.2 to 10.0 percent by weight, while the skin metals Group VIII is preferably present in an amount in the range from 0.1 to 5.0 percent by weight are, with all values calculated as if these compounds in the catalyst in elemental Condition were present. The h-rchschmelzendc inorganic carrier material with which the catalytically active metal components can be combined z. B. aluminum oxide, silicon dioxide. Zirconium oxide. Magnesia. Titanium oxide, boron oxide, strontium oxide, Hafnium oxide and mixtures of two or more such components, e.g. B. silica - aluminum oxide, aluminum oxide - silicon dioxide - boron phosphate. Silicon dioxide - zirconium oxide. Silica - Magnesia, Silica-Titanium Oxide. Aluminum oxide - zirconium oxide, aluminum oxide - magnesium oxide. Silicon dioxide - aluminum oxide - titanium oxide, aluminum oxide - magnesia-zirconium oxide or silica-alumina-boron oxide.

For clarification, some terms used in this document are defined below. The phrase "about the same pressure as" or a similar phrase indicates that the pressure at which a subsequent vessel is held is the same as the pressure in the previous vessel, reduced only by the pressure drop caused by the flow of media through it the system enters. For example, if the first catalytic reaction zone is maintained at a pressure of about 190 atmospheres, the first separation zone, ie the separation zone hereinafter referred to as the "hot separator", operates at a pressure of about 182 atmospheres. The expression "about the same temperature as" or a similar formulation indicates that there is only a decrease in temperature due to the normal temperature drop as a result of the flow of material from one part of the system to another or the conversion of sensible heat into latent heat by expansion or "flash evaporation «Where a pressure drop occurs. The term "boiling in the gasoline range hydrocarbons" indicates those liquid at normal conditions of hydrocarbons boiling at temperatures up to about 204 or 232 ⁰ C, including pentanes and heavier hydrocarbons, and - in some places - butanes. Similarly, a commonly used boiling range for gas oil is a range with an initial boiling point of about 343 "C and an end boiling point of about 566 C. The higher boiling portion thereof, comprising about 70 to 80%, ie the heavy gas oil. Is typically classified as a fraction with a Initial boiling point of about 399 "C is considered. It is noted, however, that a "light gas oil" may also have such a deep initial boiling point such as 177 ⁼ C and a final boiling point as high as about 427 ^r C. Similarly, the "heavy gas oil" can optionally have an initial boiling point as low as 343C.

The measures of the method are described below using exemplary information and values further illustrated.

The entire product exhaustion from the catalytic! Reaction zone, at a maximum temperature of about 427 C, is let into a first separation / onc, which is subsequently referred to as "Heiüabscheidcr" will. The main task of the hot separator is in converting the mixed-phase product outflow into one Mainly vapor phase, which is rich in hydrogen is. and a mainly liquid phase that contains a certain amount of dissolved hydrogen, to separate. Preferably all of the reaction product effluent is used as a heat exchange medium.

ίο to get its temperature in the range of 371 to 413 C and preferably below about W C. The mainly vapor phase from the hot separator is introduced into a second separation zone, hereinafter referred to as "cold separator"

■ becomes 5. The cold separator works at about the same pressure as the hot separator, but at a much lower temperature in the range of 16 to 60 C. The cold separator is used to enrich the hydrogen in a second, mainly vaporous phase. This hydrogen-rich vapor phase, which z. B. contains about 82.5 mole percent hydrogen and only about 2.3 mole percent propane and heavier hydrocarbons is available for use as a recycle stream for combination with the fresh black oil feed. Butanes and heavier hydrocarbons are condensed in the cold separator and drawn off from it in the form of a second, mainly liquid phase. The first liquid phase from the hot separator can be partially recycled and combined with the fresh hydrocarbon feed to serve as a diluent for the heavy constituents therein. The amount of liquid phase diverted in this manner is selected so that the ratio of the combined feed to the catalytic reaction zone, defined as the total volume of liquid feed per volume of fresh liquid feed, is preferably in the range from about 1.1: 1 to about 1.5 : 1 lies.

The remaining part of the mainly liquid phase from the hot separator is transferred to a third Separation zone introduced, hereinafter referred to as "hot flash zone". The hot flash zone will operated at approximately the same temperature as that of the liquid phase withdrawn from the hot separator, but at a much lower pressure in the range from 10.2 to 23.8 atmospheres. The main thing vapor phase from the hot flash zone mainly comprises hydrocarbons which are below a Boiling temperature of about 343 "C, and contains a" relatively small amount of hydrocarbon substances that normally come before the boiling range rem gas oil. This one to the main Vapor stream can be combined with the liquid stream from the cold separator and the Gemiscl are then introduced into a "cold flash phone" at a pressure between atmospheric pressure and sth; 4.1 atü and a temperature of 16 to 60 C.

The mainly liquid phase withdrawn from the hot flash zone is introduced into a thermal cracking reaction zone or coil at approximately the same temperature and a pressure of 10.2 to 23.8 atmospheres. The thermally cracked product effluent exits at a temperature of 466 to 510 ^T C and a pressure of 2.6 to 6.8 atmospheres. is then cooled to a temperature of about 371 ° C. and then introduced into a fourth separation zone, which will hereinafter be referred to as the "flash fractionation zone". The flü:

209 517/2!

; ige! 'Hase aus eier Flashlraklioincr / one is introduced into a vacuum column, which is raised at a pressure of ^{n <} liis ~ y miii i Ie nbsnlut. The vacuum column serves as a full 1 race. Her'.' The main task is the enrichment and separation of an asphallic back-taiuk which contains sulfur-containing compounds of molecular weight and is essentially free of distillable hydrocarbons. In most cases, gas oil flows from the vacuum column are taken off in the form of a separate light vacuum gas oil with a boiling range from 1 to 399 ° C, a medium vacuum gas oil in the boiling range from 399 to 7 ° C and a heavy vacuum gas oil that contains the remaining distillable hydrocarbons. It is clear that in the case of the cut cover sections of the various gas oil streams from the vacuum column, they are not of essential importance for the invention, but can generally be determined according to the respective wishes and requirements of the refinery and the market.

A slop wax fraction is preferably also separated off in the vacuum column, which in the first instance Line above 527 C 'boiling distillable fractions contains, but also up to about 30 percent by volume from the total distillables which boil over .W) C " can exist. Part of the slop wax fraction can be returned to the catalytic reaction zone but in general a recycle to the thermal one. Snake preferred to yield the more desirable gas oils / u increase. The amount of slop wax returned in this way is chosen so that the ratio of the united Charge / u of the thermal reaction coil above about 1.2: 1 and generally not higher than about 3.0: I lies.

One of the main advantages of the method according to the invention is that it extends the useful ones Catalyst life in connection with a catalytic reaction zone. This is based mainly due to the fact that a desulphurization to values of less than about 1.0 percent by weight is achieved with a relatively low operational severity, with the result that? the formation of polymeric products is reduced or suppressed. Furthermore, the vacuum flash column can be kept much smaller, which is an additional advantage in terms of process technology and economy of the overall process bcdeutei. The process continues to increased yields of the more valuable gas oils.

To further illustrate the features explained, the conversion of a bottom product from a vacuum column with a specific gravity of 1.0291 and an ASTM 20.0 volume percent distillation temperature of about 569 ° C. is described below in connection with the drawing as an example. Weiler still contained 4,000 parts per million nitrogen in the feed. 5.5 percent by weight sulfur. 100 parts per million nickel and vanadium and 6.0 weight percent heptane-insoluble asphaltenes. and it had a Conradson coking residue of 21.0 weight percent. The explanation takes place on the basis of a large-scale plant with a "throughput of about 1272 nr / day 11 ~>T>000l'Tae). The drawing shows the process flow" of a simplified flow diagram with the details necessary for the explanation and the understanding of the work measures are dispensable, have been removed. The depletion conditions and the compositions of the feedstock and the other material streams are provided for illustrative purposes. however, the invention is not restricted to this.

When processing the task, the To convert feedstock as far as possible into distillable hydrocarbons, which by

can be obtained in common distillation methods in commonly used fractionation systems. The Einsatzmatcrial is in a catalytic fixed bed! · Ntschwcfelungs- storage and conversion / one mixed with about 1780 Slandard-m ^x water

'5 fabric per 10 (K) I attachments, based only on the Fresh delivery exclusively of any return streams, at a catalyst bed inlet temperature of about 370 C and a pressure of about 21 ^ aUi processed. The hourly space velocity of the liquid, based only on the fresh charge, is about 0.5. and the ratio of the combined liquid feed is about 2.0: 1. According to the drawing, the feed material, in an amount of about 185.94 MoIh. by a Line 1 introduced into the system. After a heat exchange, not shown, with different hot Outflow streams the material flows into a heater 5. in admixture with a recycled one Hydrogen-rich stream coming from a line 3 and a liquid recycle stream from the bottom of the hot separator passing through line 2 is admixed. Make-up hydrogen from a suitable external source to maintain the System pressure and to replace the hydrogen consumed in the overall process Line 4 introduced. The total feed to the heater is at a temperature of about 260 C. This temperature is about 37! C increased, measured at the inlet to the catalyst bed.

The total charge heated in this way flows through a line 6 into a catalytic solid reaction zone 7. The catalyst arranged in the reaction zone 7 is composed of 88.0 percent by weight of aluminum oxide and 12.0 percent by weight of silicon dioxide. United with 2.0 percent by weight nickel and about 16.0 percent by weight molybdenum, calculated as elemental metals.
Component analyzes of the total charge for

Reaction zones are in the table below! compiled. In the table includes there? material the line 3 both returned and top-up water, the line 2 identifies there ' liquid return material from the hot separator 9 and the line 1 carries the entire charge.

Table I.
Feed to the reaction zone

__

Component. Mole h

nitrogen

hydrogen

Hydrogen sulfide

management

11.07 and 1.85! 12.93 8430.09 \ 175.52! 8605.61

739.02

26.36

765.38

lorlsct / iiiiii

il. MoI Ii

methane

Alhan

I'ropan

Butane

Pentanes

Witches

C ₇ -KiO C

160 to 270 C.
270 to 343 C.
343 to 399 C.
399 to 527 C.

527 C and

about it

Residue

Mission Statement

119.04

133.14

67.56

24.49

6.60

4.70

2.00

0.24

IxittMlL '

31.82

7.53

4.17

2.06

0.92

1.29

3.19

11.23

16.25

22.75

67.16

9.27 78.78

1 50.86

140.67

71.73

26.55

7.52

5.99

5.19

11.47

16.25

22.75

67.16

9.27

78.78

185.94

Component. M-M h

nitrogen

hydrogen

Hydrogen sulfide

methane

management

10

ι:

12.92
7679.21

906.43
1188.95

9.40 7345.65

856.33 1128.48

1.67 158.04

23.74 26.65 il. MdI Ii

Athan

propane

Butane

Penlanc
1 lcxanc
C- to 160 C
160 to 270 C
270 to 343 V.
343 to 399 C
399 to 527 C
527 C and
about it

Residue

160.61
8 ⁽ >, 52
38.85
14.55
17.60
32.10
68.54
51.51
50.89

129.45

17.61
149.72

1 ciuini! St.

146.30

81.39

34.93

12.81

15.15

02/26

47.20

20.62

7.6 ^

1.81

6.78

3.76

1.86

0.83

1.16

2.88

11/10

14.63

20.48

60.47

8.34 70.94

The effluent formed by the conversion product which flows in mischphasigem state by a ² S Leitung8 at a 'temperature of about 427 C is used as Wärmcc-ustauschmittel and then introduced into a hot separator 9 at a temperature of 413 C and a pressure of about 206 atü. Line mainly vapor phase is withdrawn through line 10 and a mainly liquid phase is withdrawn through line 12. In this document, the expressions "mainly vaporous" or "mainly liquid" characterize the state of an individual stream in which the main part of the components present is normally gaseous or normally liquid under standard or normal conditions. At least a portion of the liquid phase withdrawn from the hot separator 9 is branched off through line 2 for combination with the fresh hydrocarbon feedstock, it serves as a diluent for the heavier constituents of the feedstock. The amount of this recycle stream is 460.15 moles per hour, giving a combined liquid feed ratio of 2.0: 1.

The separation of the reaction zone outflow in the hot separator 9 is shown below Table II reproduced, with the line 8 the Feeding for the. Separator (i.e. the reaction zone effluent), line 10 is the vapor phase and line 12 is the net flow liquid phase, without the anicii recycled through line 2. mark.

Tables
Analysis of the Streams from the Hot Separator From Table II it can be seen that the material flowing through line 10 consists of 75.5 mole percent hydrogen and only about 1.35 mole percent pentane and heavier hydrocarbons which are liquid under normal conditions. It is therefore mainly a gaseous phase. The stream flowing through line 12 comprises about 19.9 mol percent of butanes and lighter fractions, not counting hydrogen, which is dissolved in the heavy hydrocarbons, and is therefore to be addressed as a mainly liquid phase.

The portion of the bottom flow from the hot separator that is not branched off through line 2 flows on through line 12 into a hot flash zone 13. A pressure reduction valve (not shown in the drawing) brings about a pressure reduction; the current then enters the Hcißflashzone 13 a, atm at a pressure of about 17 and a temperature is set from about 408 ⁰ C. As the below, the main task of the hot flash zone 13 in a concentration of the heavier components in a liquid phase, then serves as a feed to a thermal cracking coil 17. From Table III it can be seen that the vapor phase line 14 comprises about 89.2 mole percent boiling below about 270 ⁰ C material What ^ rstofl not counting, while the liquid stream of line 16 is about 6.3 mole percent. Not counting hydrogen, includes.

Table III
Analysis of the currents from the hot flash zone

Component. Mole h

Line 14 I 16

fio

nitrogen

hydrogen

Hydrogen sulfide

methane

Ethane

propane

Butane

Pentanes

Hexanes

1.45

151.87

22.47

27.49

6.15

3.36

1.61

0.69

0.93

0.22 6.17 1.27 1.16 0.63 0.40 0.24 0.14 0.23

I-. -. rt ~

H·. ihli

FLS 399 (

t. and oaruiVi

The liquid phase of the line 16 is mixed with about 1.0 percent by weight of water vapor of 22.5 atü, and the mixture ι rhi at a temperature of about 393 C and a pressure of about 11 atü in the thermal coil Ί7 The thermal g-? Cracked product outflow, which has a pressure of about 3.7 atü and a temperature of about 499 ^r C, is called after cooling through a line 18 into a rectification flash fractionation zone 19. at a temperature of about 371 C and a pressure of about 3.7 at g. a vapor phase is withdrawn from flash fractionation zone 19 through line 20 and a liquid phase through line 24. The latter is introduced into a vacuum flash column 25 at a temperature of about 399 C. The vacuum column works at about 25 mm Hg absolute, the pressure is brought about by conventional vacuum ejectors, which are not shown in the drawing. The separation brought about in the flash fractionation zone 18 is shown in Table IV below, which also contains the read-out analysis of the thermally cracked product discharge flowing in through line 18. Wa.sscr is not included.

Table IV

Analyzes of the flows of the Hashfraklionierzone

4S

Component. Mol II

nitrogen

hydrogen

Hydrogen sulfide.

methane

Ethane

propane

Butane

Pentanes

llcxanc

C ₇ to 160 C

160 to 270 C

27Γ, up to 343 C.

343 to 399 C

399 to 527 C

527 (and above.
Residue

ix

0.22 1 1 .XV

3.6H 22.34 16.93 22.40 16.53 17.77 14.55 33.83 50.47 30.33 24.49 56.XS 10.00 39.41

management

0.22 II. 82

3.65 22.23 16.70 21.92 15.87 16.56 13.06 28.31 33.80 10.29

2.75

0.26

0.05

0.03

0.11

0.23

0.48

0.66

1.21

1.49

5.52

16.67

April 20

21.74

56.62

10.00

39.41 1; ie au ·; the HeilJabseheider 9 by the Leu !. "iiie / .i-aene. mainly Jamptiorrn.ge

■ ii \ i, au a temperature son t.-iwa 4 ' ¹ J -μ iid at emem ^:) ruek', on about 2u4aiu; n den;> before: dL-r Il introduced. A * \ a ^ cr ^ oifreiciie '• rmiiie!' Has been released by the Le: .ung3. iiJ for the purification with the coals... Ui i-ia main liquid phase> e v. It is withdrawn from your receiver 11 through a line 35

■ the K.aiiai> cheider Hcr ^ cigetliiirte! ren I from OcT riacn ^ iehenden table \ can be seen, ν e / üuiic'n the line 3 LrganzungswasserMoil liigerechnei is.

Table V
Analyzes of the cold separator flows

and Wed

i'h.r-j irküh !; K.ut-

Component. Mole h

Lcitunö

nitrogen

hydrogen

Hydrogen sulfide.

methane

Ethane

propane

Butane

Pentanes

Hexanes

C ₇ to 160 C

160 to 270 C

270 to 343 C

343 to 399 C

399 to 527 C

527 C and above.
Come back

9.29

7274. "0

739.02

1091.19

133.14

67.56

24.49

6.60

4.70

2.00

0.24

0.11 70.95 117.31 37.29 33.16 14.03 10.44

6.21 10.45 24.02 46.96 20.62

1.81

The vacuum flash column 25 is used for concentration of the residue, which flows off in an amount of 39.41 MoITi through a line 28, and to Separation of a light vacuum gas oil (LVGOl and a heavy vacuum gas oil (HVGO) can be withdrawn through lines 26 and 27, respectively. The heavy vacuum gas oil with a boiling range of 399 up to 566 C falls in an amount of about 66.62 mol / h on. the light vacuum gas oil at a rate of 58.45 mol / h. Lighter ones boiling below 160 C. Shares are removed from the vacuum flash column 25 through the jet suction devices not shown in the drawing removed.

For the sake of completeness, the flow diagram also shows a cold flash zone 25, which in the Ausfübrungsbcbeispiel a separation of Mixture of the vapors of the hot flash zone (line 14), the vapors of the Flashiraktionierr.onc (line 20) and the liquid from the cold trap (Line 15) brings about. In the case of a technical system, the vapors from the flash fractionation zone because of their relatively high olefin content are expediently obtained separately. Condition analyzes. from which the separation brought about in the cold flash zone 21 emerges are in compiled in Table VI below.

15th

Table VI Analyzes of the currents of the cold allash zone

16

Table VU total product yields

BeManJleil. Mole h

nitrogen

hydrogen

Hydrogen sulfide

methane

Athan

propane

Butane

Pentanes

Hexanes ... · .....

C ₇ to 16O = C ...

160 to 27O ⁰ C ..

270 to 343 ° C ..

343 to 399-C ..

399 to 527 = C .. 527 = C and above

Residue ....

feed 1.78

234.64

143.43 87.01 56.01 39.31 27.92 23.46 24.44 54.45 86.65 35.64 13.52 3.99

0.01

management

1.78

232.53

96.75

82.63

47.12

26.24

11.87

4.84

2.54

1.86

0.05

2.11

46.68

4.38

8.89

07/13

16.05

18.62

21.90

52.59

86.60

35.64

13.52

3.99

0.01

Butane

Pentanes

Hexanes

C- to 160 C

160 to 270 C

270 to 343 C

343 to 399 "C

399 to 527 C ....
527 ^L C and above
Residue

MoI h

2S.5S 24.67 25.93 59.97 103.32 55.68 35.26 60.61 1/10 39.41

The sulfur content of the distillable coal water sol products ⁶ is about 0.83 percent by weight.

With previously known Verubeitungsweise d, e no thermal snake as an integral ted's Must have the processing path of the catalog

Under normal conditions gaseous fractions are 30 * "; f ^ XJJ ^ _8b is56 ° C, which is a very essential part of a line 22 to a catalyst (not shown) . during which the kata- -1 1 u ~: Tvi « _rm oiKoriincTiinopn flnssiee extension of the tjeiricusuau«. ·, _{jl |} ^. ^

drawn, while under normal conditions liquid hydrocarbons including butanes for Further separation by fractionation can be taken through a line 23. The total product yields excluding the

lytic composition

- - - ■ ii - 117 ..:

technically and economically

wesciuuv.ii & ii uu _Un . _O

The total product yields exclusively the drive according to the invention to an increase in under normal conditions in gaseous proportions, but catalyst life around 50 to 80%, which is a including butanes and the very substantial extension of the actual conditions under normal conditions liquid hydrocarbons, which means from the 40 operating periods. Furthermore, a bchl G daily smaller vacuum column, in which the explanatory

Normal

conditions liquid K 40 means driving periods. G

Vacuum ejectors and the device for a considerably smaller vacuum column, in which recovery of light ends (line 22) obtained technical example can be the vacuum column are shown in Table VI below, corresponding to a reduction in the nominal aggregate. messcrs should be smaller from 335 to 262 cm.

corresponding to a Vegg Messcrs from 335 to 262 cm smaller

1 sheet of drawings

Claims (1)

954 Patent claims: ! \ ei laliieii / lh conversion and desulphurisation L ¹ IiH ", kuhlenwa.serstoffeinsat / maicjrials. of '" the minimum 10 ",, boil above 566 L' and among other things L-HU-Ii relatively low metal level. especially less al> , about i 5 (ι parts per million Gesamimelalle calculated in the elemental state, but a high Sehwefelgehalt. iev.ichtsprozent particular more than 2. (1 C, has. liefersiedender to form destillierharer Kohlenwassersh> iip. 'Dukie reduced sulfur content. wherein lI.i- hydrochloride feedstock according to r.rhi: /uni.· iii of a catalytic reaction zone at increased pressure in the presence of hydrogen to remove sulfur compounds and generate low-boiling hydrocarbons, the resulting reaction mixture separated and the resulting liquid fractions of a further cracking Reaction with subsequent work-up of the reaction products are subjected, characterized in that one