DE3403979A1 - METHOD FOR HYDROCRACKING HEAVY OIL - Google Patents

Description

Patent Attorneys G RAM M + LI NS SSiSTSSJSi ^Mamm

D-3300 Braunschweig

1. Her Majesty, in right of Canada, phone (0531) 80079 represented by the Minister of ■ Telex · 0952620 Energy, Mines and Resources, Canada

2. Petro-Canada Inc.

Calgary, Alberta, Canada Attorney File 823-1 DE -1

Date Feb. 1, 1984.

Process for hydrocracking heavy oil

The invention relates to a method for hydrocracking a heavy hydrocarbon oil, a significant proportion of which has a boiling point higher than 524 ° C, with a pulp from the named hydrocarbon oil and a carbon residue Additive in the presence of 500 to 50.COO s.c.f. Hydrogen per Barrel of said hydrocarbon oil it by a limited Hydrocracking zone is passed, which is kept at a temperature .zwisehen 375 ° and 500 ° C, a pressure greater than 3.5 MPa and a space velocity of up to 4.0 volumes of the heavy Hydrocarbon oil per hour per volume of the capacity of the Hydrocracking zone from which a mixed effluent is withdrawn, comprising a gaseous phase of hydrogen and vapor. Hydrocarbons and a liquid phase of heavy Contains hydrocarbons, and then is split into a gas stream of hydrogen and vaporous hydrocarbons and a heavy hydrocarbon liquid stream.

Hydrocracking process for converting heavy hydrocarbon oils in light and medium heavy naphthas of good quality

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Splitting of the feed materials into oil and gas are well known. These heavy hydrocarbon oils can be such materials trade as petroleum, atmospheric tar residues, Vacuum tar, heavy cycle oil, coal liquids, Crude oil residues, topped off crude oils and the heavy pitch oil that is extracted from oil sands. Of particular interest are the ones from Oil sands extracted oils, the materials with a wide boiling range contain from naphthas to kerosene, gas oil, pitch and the like. and a large proportion of the material with a boiling point above 524 ° C, equivalent atmospheric boiling point.

The heavy hydrocarbon oils of the type mentioned above tend to contain nitrogen and sulfur compounds in large concentrations to have. In addition, such heavy hydrocarbon fractions often contain large amounts of metal / organic Contaminants that are extremely detrimental to various catalytic processes that follow such as a hydro refining. from The metallic impurities are those that contain nickel and Vanadium obtained, most commonly, although other metals are also common. These and other metallic contaminants often occur in bituminous materials as organometallic Compounds with a relatively high molecular weight. A significant one Amount of organometallic complexes are made with asphalt material coupled and contain sulfur. In catalytic hydrocracking processes, the presence of large quantities is detrimental of asphalt material and organometallic compounds, of course significantly the activity of the catalyst in terms of the cracking removal of nitrogen and sulfur-containing and oxidized compounds. A typical athabascabitumen can contain 51.5% by weight of material with a boiling point above 524 ° C, 4.48% by weight Contains sulfur, 0.43 wt% nitrogen, 213 ppm vanadium and 67 ppm nickel.

As the reserves of conventional crude oils decrease, they have to Heavy oils are quality-improved to meet the requirements

j meet. With this quality improvement this will ^:

heavier material is converted into lighter fractions, and \

Sulfur, nitrogen and metals have to be largely removed; will.

This can either be carried out by a coking process, for example by delayed coking or by fluidized bed coking, or by a hydrogen supply process such as, for example . _t by thermal or catalytic hydrocracking. The distillate yield in the coking process is about 70% by weight, and this process also results in about 23% by weight of coke as a waste product, which cannot be used as fuel because of the low nitrogen-to-carbon ratio and the high mineral and sulfur content. Depending on the process conditions, the hydrogenation process can produce a distillate yield of over 87% by weight.

More recent work deals with an alternating process sequence, in which hydrogen is supplied at high pressures and temperatures; the results have been promising. In this process, hydrogen and heavy oil are pumped up through an empty, tubular reactor, without it In the presence of some kind of catalyst. It was found that the High weight molecular compounds in lower boiling areas hydrogenate and / or hydrocrack. At the same time, desulphurisation, Demetallization and nitrogen removal reactions instead of. Reaction pressures up to 24 MPa and temperatures up to 490 ° C were achieved.

In thermal hydrocracking, the main problem is with the coke or the solid deposits in the reactor, especially if the process is carried out at relatively low pressures; this can lead to costly business interruptions. Deposits form in the top of the reactor, where the partial pressure of hydrogen and the ash content are lowest. Higher pressures reduce reactor contamination. At 24 MPa

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and 470 ° C, the coke deposit can largely be eliminated. However, operating ancestors at high pressures lead to higher pressures Investment and procedural costs.

It is known that mineral constituents are one in the starting product play an essential role in coke deposition. US patent 3,775,296 discloses that starting material has a high mineral content (3.8% by weight) have a lower tendency to deposit coke in the reactor as starting material with a low mineral content (less than 1% by weight). Other studies have shown that one high mineral content no apparent effect on pitch conversion and desulfurization, but suppressed coke build-up in the reactor and general reaction fouling.

It has also been shown earlier that coke deposition in the reactor can be suppressed by recycling part of the high-boiling distillates in the lower area the reaction zone. According to US Pat. No. 3,844,937, there is no coke in the reactor when the mineral concentration of the reactor liquid is between during thermal hydrocracking 4 and 10 wt% is maintained. It appears that during the hydrocracking process, carbonaceous material is used instead is deposited on the reactor wall of solid particles and thereby can be discharged with the reactor drain. This indicated the possibility of a coke carrier continuously in the Introduce or derive the reactor from the reactor.

The supply of a coke carrier has been suggested in U.S. Patent 3,151,057, whereby sand, quartz, clay, magnesia, zircon, beryl or bauxite can be used as a carrier. These carriers can be regenerated after their use by heating the contaminated substrate with oxygen and steam about 1090 ° C; a regeneration product gas with a considerable proportion of hydrogen is thus obtained. The Canadian Patent 1,073,389 and US Patent 4,214,977 show that the ■ supply of coal or a coal-based catalyst to

a reduction in coke deposition during hydrocracking _; leads. Kohladditi ve serve as a place for the deposition of, coke precursors and thus give the possibility of their removal i from the system.

■ The use of such catalysts based on coal is permitted yes no process at lower pressures and higher conversions. The use of coal and cobalt, molybdenum and aluminum on carbon catalysts is described in Canadian Patent 1,073,389, while U.S. Patent 4,214,977 uses iron-carbon catalysts and Canadian Patent 1,124,194 uses of fly ash.

A process for hydrogenation is described in US Pat. No. 3,775,286 of coal, the coal either being impregnated with aqueous iron oxide or dry iron oxide powder hydrate physically mixed with powdered coal. However were the conversion rates using the physical Mixture pretty bad compared to impregnated charcoal.

The .Erfindung is based on the task of an inexpensive, available Carbon based additive in a heavy hydrocarbon use feedstock so as to reduce the problems that arise during the hydrocracking process . Deposits forming in the reactor result.

This task is based on the method explained at the beginning solved in that the carbonaceous additive a Powder mixture, which is obtained by intimately mixing dry

carbon or fly ash particles with dry particles a metal compound obtained, the latter being a ground MetalIsalζ can be.

This process largely prevents the formation of carbonaceous Deposits in the reaction zone. These deposits, the quinoline and insoluble benzene organ material, mineral

constituents, metals, sulfur and some soluble organ benzene material may contain are hereinafter referred to as "coke" deposits designated.

The dry mix is of course much cheaper to produce than the usual metal impregnated additives. Simultaneously there is a favorable comparison with the impregnated additives in terms of the reduction in coke precursors and in terms of the prevention of coke deposits in the reaction zone.

The inventive method is particularly suitable for Treatment of heavy oils with a high proportion, preferably of at least 50 volumes ^, with a boiling point above 524 ° C and with a wide boiling range of materials from naphtha to kerosene, gas oil and pitch. The procedure can be proportionate low pressure, preferably in the range of 3.5 to 24 MPa, without coke formation in the hydrocracking zone.

Although the hydrocracking in various known reactors in either can be carried out upstream or downstream, it is in particular suitable for a tubular reactor through which feedstock and gas are passed upwards. The expiry on The reactor head is preferably divided into a hot separator from which the gaseous stream is sent to a low temperature, high pressure separator can be conducted, where it is divided into a gaseous stream of hydrogen and lesser fractions gaseous hydrocarbons and a liquid product stream, which contains light oil.

The metal compound used for the additive is one that under the action of hydrogen and hydrogen sulfide turns into Metalsulfide transformed. The metal compound can be an oxide of the Metal, a metal salt, e.g. sulfate, sulfide, chloride, fluoride, Nitrate, oxalate or carbonate or a metal hydroxide. That

Metal is typically a catalytically active metal such as iron, cobalt., Nickel, molybdenum, chromium, tungsten, vanadium, Zinc or the like. A particularly preferred compound is iron sulfate.

The metal salt used in connection with this invention as well the carbonaceous material preferably have very small particles, for example smaller than 60 mesh (Canadian Standard Sieve); preferably a material which will pass through a 100 mesh screen is used. Still is it is possible to achieve the advantages of the invention with larger particles up to 1/4 inch. A typical additive mix contains 5 to 95 wt% metal salt, usually the catalyst is mixed with the heavy oil starting material in a ratio of 0.1 to 5% by weight based on the heavy oil starting material, although this can vary up to 0.01 to 25% by weight based on the starting material.

The additive can through fine grinding, drying and subsequent Screening of a suitable coal can be produced on a smaller than 100 mesh. A certain amount of a 100-mesh metal salt is slowly added to the coal in a mixer; the batch is then mixed for about 10 minutes. Some metal salts must be dried before they can be sieved to 100 mesh in order to reduce moisture or des To reduce the hygroscopic property of the water content of hydration. Drying can be carried out at around 90 ° C for three hours.

The particle sizes can be smaller or larger than 100 mesh depending on the reactor geometry and the tendency to coke of the heavy hydrocarbon oil feedstock. The dry mixing process also enables the Adjust the size of the metal 1 salt particles and the coal independently. For example, the particle size of the coal be chosen larger, so for these particles a longer one

To achieve residence time, which allows greater liquefaction.

In connection with the invention it was found that particularly good results are achieved when the metal salt is mixed is mixed with coal, preferably lignite or bog coal, or with fly ash.

Coal can generally be defined as a mineral consisting of coked plants. There are many different types of coal including lignite, bog coal and anthracite. Brown coal is a material that lies between peat and coal in its character and contains a significant proportion of highly volatile · Has hydrocarbons. Pitch coal is the most common Type and is slightly harder than lignite, with a higher carbon content and a lower volatile content Hydrocarbon. Bog coal lies between in its character Brown coal and pitch coal. Anthracite is a very hard coal with a high carbon content and a very small one Content of volatile components. Coke is the solid product which results when the coal is heated and consists of a porous, hard carbon mass that is very little volatile Contains shares.

In the method of the invention, the additive is used in the first place Line used to suppress coke formation and remove coke deposits. It was found to be particularly useful Metal salt with brown coal or bog coal or fly ash to use instead of coke or semi-coke. For example, it has been found that under hydrocracking conditions Lignite extensively, pitch coal, coke or semi-coke but the least hydrogenated. The extent of the hydrogenation of bog coal is located between these extremes. Therefore it should be an ideal pulp-shaped Partially hydrogenate the catalyst carrier for this hydrocracking process, which leads to a reduction in the particle size, whereupon these particles should leave the product stream and carry with them some deposited coke. For these reasons it is

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it can be seen that a coke or semi-coke carrier for this task not working satisfactorily.

I "■

According to a preferred embodiment, these will be difficult Hydrocarbon oil feedstock and the metal 1 carbon additive mixed in a raw material tank and pumped through a vertical reactor together with hydrogen. At the top of the 'Hydrocracking zone can mix the liquid gas in different ways Can be separated in ways. This can be done, for example, in a hot separator, which is between 200 and 470 ° C and under the pressure of the Hydrocracking reaction is held. The heavy hydrocarbon oil product coming from the hot separator can either be recycled or be directed to a second treatment.

The gaseous stream coming from the hot separator contains a mixture of hydrocarbon gases and hydrogen and is in a low temperature high pressure separator and cooled separated. By using this type of separator, the output gas stream contains predominantly hydrogen with some impurities such as hydrogen sulfide and light hydrocarbon gases. This gas stream is passed through a scrubber and the scrubbed hydrogen is recycled as part of the hydrogen feed to the hydrocracking process. The purity of the recycled hydrogen gas is maintained by adjusting the Washing conditions and by adding additional hydrogen.

The liquid flow from the low temperature high pressure separator represents the light hydrocarbon product of the present Proceedings and can result in secondary treatment.

A portion of the Metal 1-Kohl e-A.ddi ti vs is used together with the heavy oil product transferred from the hot separator and is found in the 524 ° C pitch fraction. However, since this is a very cheap one If it is an additive, it is not worth recovering and it can be burned or gasified together with the pitch. The Concentrations

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Tration of the metal 1-carbon additive in the feedstock is usually between 0.1 and 5.0% by weight, preferably at about 1.0% by weight. The metal salts transform under hydrocracking conditions in metal sulfides. ;

For a better understanding of the invention, reference is made to the accompanying drawing, which is a preferred diagram Embodiment of the invention shows.

Heavy hydrocarbon oil feedstock and a metal salt-coal additive are mixed together in a raw material tank 10 to form a slurry, which is fed via a feed pump 11 by a To I on1 line 12 is pumped into the floor of an empty tower 13 which forms a reaction chamber. At the same time, recycled hydrogen and additional hydrogen are discharged via line 30 also routed through the supply line 12 into the tower. At the upper end of the tower 13 is a gas-liquid mixture withdrawn through a line 14 and fed into a hot separator 15, where the drain coming from the tower 13 is separated becomes a gaseous stream 18 and a liquid stream 16. The latter consists of heavy oil that is collected in a chamber.

Alternatively, it is possible to connect to the line with the liquid flow 16 to connect a branch line that has a pump into the supply line 12 and serves as a return for Return of the liquid stream, the metal sulfide particles and contains carbons from the hot separator 15, into the raw material slurry of the tower 13.

In a further modified embodiment, the line leads of the liquid stream 16 in a cyclone separator, the the metal sulfide particles and the carbon particles from the liquid stream separated and these separated particles returned to the starting pulp of the tower 13, while the remaining Liquid is collected in the chamber 17.

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The gas stream emerging from the hot separator 15 is via a ! Line 18 in a high pressure low temperature separator 19

'heads and here divided into a gas stream that is rich in

Hydrogen and is withdrawn via a line 22, and in an oil product, which is withdrawn via a line 20 and in a chamber ! mer 21 is caught.

The hydrogen-rich stream 22 is passed through a packed scrubbing tower 23 passed and washed here with a washing liquid 24, which is passed through the washing tower by means of a pump 25 and a return pipe 26. The washed, water-rich Stream exits the scrubber via line 27 and is mixed with fresh make-up hydrogen, which is via a Line 28 is fed, and is then returned via a Return gas pump 29 and a line 30 in the tower 13.

Further preferred embodiments of the invention are provided below illustrated by non-restrictive examples.

. example 1

An additive was produced by crushing and sieving a bog coal to a size smaller than 200 meshes. This material was then mixed with a predetermined amount of egg sensu Ifat, dried, crushed and sieved to a size smaller than 200 meshes. The iron sulfate was dried beforehand because it occurs as a heptahydrate, namely as FeSO ₄ .7H ₂ O under normal conditions. This salt is hygroscopic and forms agglomerates that clog the sieve openings. The heptahydrate was dried to a monohydrate FeSO ₄ -H ^ ₁ O by heating to 90 ° C for about three hours. The dried iron sulfate was then crushed and sieved and then slowly added to the charcoal in a blender and mixed with it for about 10 minutes. The resulting mixture was placed in a drum and rotated for about 4 hours.

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The properties of the dry blended additive are listed in Table 1 below along with the properties of a typical impregnated additive.

Table 1: Analysis of a dry mixed and an impregnated one Additive

dry mixed impregnated sulfur Weight% 4.81 4.72 ash Weight% 21, 76 20.8 insoluble pentane Weight% 93.6 - insoluble toluene Weight% 93.0 - Vanadium ppm 180 79 nickel ppm 72 1 19th iron Weight% 8.78 8.96 carbon Weight% 41.31 41, 05 hydrogen Weight% 2.97 3.06 nitrogen Weight% 0.51 0.50

The size distribution of the two additives is shown in Table 2 listed.

Table 2: Dry sieve analysis of dry mixed additive and impregnated additive

Additive dry mixed impregnation

was standing
Size arf mesh Gewi c
pm (σ) ht the end prey Certainly
L <L cht the end prey -100 - +200 147-74 5, 17th 2 , 5 4, 66 ¹ 2 , 9 ¹ -200 - +325 74-43 48, 35 23 , 0 42, 38 26th , 4 -325 <43 156, 43 74 , 5 113, 51 70 , 7

1 . +200 stitches

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ι 2

A Cold Lake vacuum residue was used as the starting material

! uses the following properties:

: Table 3: Properties of the Cold Lake starting material

; Density specific gravity sulfur ash Conradson carbon residue insoluble pentane insoluble toluene asphal te'ne carbon hydrogen nitrogen vanadium nickel iron sediment (extraction) water (distillation) pitch (boiling point above 524 ⁰ C)

2. One. Territory in western Canada

⁰ API. 4.8 ■ 15/15 ° C 1.038 Weight% 5.82 Weight% 0.05 Weight%. 19.8 Weight% 22.7 Weight% 0.07 Weight% 22.6 Weight% 82.90 Weight% 9.96 Weight% 0.68 ppm 251. ppm 93 ppm 13th Weight%. traces Weight% traces Weight% 85.1 0

A cut pulp from the above starting material and one percent by weight the dry blended additive was manufactured and used as feedstock for a hydrocracking plant, as shown in the accompanying drawing.

The reactor was operated under the following conditions:

Reactor temperature - ⁰ C

Pressure MPa

liquid hourly space velocity

450 13.9 0.75

34Π3979

recirculated gas velocity m ³ / h recirculated gas purity (hydrogen) vol% length of the drain h

5.9 85 422

The results obtained from this procedure were as follows:

Pitch (524 ° C) conversion sulfur conversion Liquid product yields C + Liquid product yield (C.

Gases

Hydrogen consumption

Weight% 87.5 Weight% 65.5 vol% 106.1 Weight% 92.7 Weight% 5.7 m ³ / ton 221.9

At the end of the process, there were 143 grams of solid deposits found in the system.

The results can be compared with a process sequence in which an impregnated iron-carbon additive was used. A slightly different Cold Lake raw material was used, the properties of which are given below:

Table 4: Properties of the Cold Lake raw material (used with impregnated additive)

Specific gravity of sulfur ash

CCR.

insoluble pentane asphaltenes insoluble toluene Carbon hydrogen nitrogen vanadium nickel

15/15 ° C wt.% Wt.% Wt.% Wt.% Wt.% Wt.% Wt.% Wt.% Wt.% Ppm ppm

1, 026

5.16

0.064

18.2

21, 0

21.0 0.03

82.93

10.29 0.57 255

92

_

■ iron
"Viscosity " .. Viscosity, pitch

ppm 82 ⁰ C 10 cSt at 99 ⁰ C 52 7 0 cSt at % 1489 Weight 72.95

The following process conditions were used for the process sequence complied with: -

Reactor temperature ^{0 C}

Pressure MPa

liquid hourly space velocity recirculated gas velocity m ³ / ton recirculated gas purity (hydrogen) vol% duration of the process sequence. H

448 13.9 0.75 5.9 85 513

The following results were obtained:

Pitch conversion Sulfur conversion Liquid product yield (C ₄ +) Liquid _{product yield (C 4} +)

- C ₃ gases

Hydrogen consumption

Weight% 8 5.5 Weight% 55.9 vol % 102.7 Weight% 92.3 Weight% 5.1 m ³ / ton 196.8

The total build-up of solids during this process sequence was '72 gr, which differs advantageously from the 143 gr solid deposits in the process with the dry mixed additive. Under the same process conditions, a process without Metal 1-Carbon Additi ν can only be used Carry out a very short period of time before severe buildup or clogging occurs. A process with Athabasca bitumen at 450 ° C and a higher liquid hourly space velocity of 3.0 without the use of an additive resulted in 6,600 g deposits after 384 hours.

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The properties of Athabasca bitumen, the process conditions The genes and the results obtained in this procedure are as follows listed.

Properties of Athabasca * bitumen:

Specific gravity of sulfur

ash

Conradson Carbon Residue Insoluble Pentane insoluble benzene vanadium content Nickel is included T otal acidity 1 total base number carbon hydrogen

Fabric
(Dohrmann microcoulometer)

chlorine

viscosity
Bad luck (524 ⁰ C)

15/15 ° C 1, 009 Weight% 4.48 Weight% 0.59 Weight% 13.3 Weight% 15.5 Weight% 0.72 ppm 213 ppm 67 mg KOH / g 2.77 mg KOH / g 1, 89 Weight% 83.36 Weight% 10.52 Weight% 0.43 Weight% 0.00 cst at 38 ° C 10,000 Weight% 51, 5

* An area in western Canada with tar sands.

Process conditions:

Amount of additive pressure

Reactor temperature Duration of the process% by weight
MPa
⁰ C
H

liquid hourly space velocity
recirculated gas velocity m ³ / h recirculated gas purity (hydrogen) vol%

10.44 450 384 3.0 5.6 85

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Results:

[ Pitch conversion
! Sulfur conversion j Hydrogen consumption

I-

! Liquid product yield, liquid product yield I Total solid deposits in the system

These results clearly show that the iron-carbon additives very effective in preventing solid build-up are. The dry, mixed and impregnated additives have approximately the same properties in terms of coke suppression.

Weight % 60.6 Weight% 29.9 m ³ / ton 58.2 vol% 100 Weight% 94.2. G 6600

Gr / Gru. ·

Claims (12)

Patent attorneys GRAMM + LINS D-3300 Braunschweig 1. Her Majesty, in right of Canada, _{Te | efon} . (0531) 8007! represented by the Minister of _Telex; 0952620 Energy, Mines and Resources, Canada 2. Petro-Canada Inc. Calgary, Alberta, Canada Attorney File 823-1 DE-1 Date Feb. 1, 198 / Patent claims: (1. Process for the hydrocracking of a heavy hydrocarbon oil, a significant portion of which has a boiling point higher than 524 ° C, wherein a slurry of said hydrocarbon oil and a carbonaceous additive in the presence of 500 to 50,000 scf hydrogen per barrel of said hydrocarbon oil is passed through a Limited hydrocracking zone is passed, which is maintained at a temperature between 375 ° and 500 ° C _5, a pressure greater than 3 _; 5 MPa and a space velocity of up to 4.0 volumes of the heavy hydrocarbon oil per hour per volume of the capacity of the hydrocracking zone from which a mixed flow is withdrawn, which contains a gaseous phase of hydrogen and vaporous hydrocarbons and a liquid phase of heavy hydrocarbons, and is then split into a gas flow of hydrogen and vaporous hydrocarbons and a liquid flow of heavy hydrocarbons, characterized in that the carbonaceous additive is a powder mixture obtained by intimately mixing dry coal or fly ash particles with dry particles of a metal compound. 2. The method according to claim 1, characterized in that the coal is a brown coal or bog coal. 3. The method according to claim 2, characterized by such a metal 1 compound, which is in metal under reactor conditions sulfide transformed. I4. Method according to claim 2, characterized in that the i Metal compound is a metal salt. 5. The method according to claim 4, characterized in that the Metal compound is a catalytically active metal, selected from iron, cobalt, nickel, molybdenum, chromium, tungsten, ■ Vanadium and zinc. 6. The method according to claim 5, characterized in that the Metal compound is an iron salt. 7. The method according to claim 6, characterized in that the ; Iron salt is an iron sulfate. 8. The method according to claim 1, characterized in that the .Called slurry about 0.01 to 25% by weight of the additive mentioned [contains. 9. The method according to claim 8, characterized in that the; Slurry contains 0.1 to 5% by weight of said additive. ! 10.Verfahren according to claim 2, characterized in that - that the Additive particles are smaller than 6 0 mesh. 11.Verfahren according to claim 1, characterized in that the 'carbonaceous additive is fly ash. 12. The method according to claim 11, characterized by such Metal 1 compound, which under reactor conditions in Converts metal sulfide. m attorneys
Gr ^ mm + Lins
Gr / Gr.