SE454701B - PROCEDURE FOR DELAYED COOKING OF A COOKING OUTPUT MATERIAL - Google Patents

Description

And according to the invention, the contents of the drum are heated to a temperature higher than the temperature used during the coking step, to remove volatile combustible materials therefrom, thereby producing a coke with a reduced coefficient of thermal expansion. Although the present invention is applicable to a variety of methods of delayed coke for the production of coke, the invention is particularly applicable to the production of needle coke and in particular to high quality crystalline coke from starting materials treated by thermal heating and / or cracking and / or removal of non-crystalline substances. As an example, a method which applies all of these three steps is described in U.S. Patent 4,108,798.

According to the present invention, delayed coking is achieved by the general method previously known, wherein coking starting material is continuously heated in a coke heater and introduced into a coke drum until the contents reach a desired filling level, after which the coke drum is disconnected from the coke removal stream. According to the present invention, the cooking drum is operated at lower temperatures from 415 to 4 ° C, preferably from 42 ° to 40 ° C, and after the cooking drum has been disconnected from the stream, i.e. the coking starting material is no longer introduced into the coking drum, the contents of the shut-off coking drum are heated to a temperature which is at least 10 ° C higher than the coking temperature (preferably at least 15 ° C and in particular at least 20 ° C higher than the coking temperature) and which temperature is at least 450 ° C, preferably at least 460 ° C and not higher than 500 ° C, preferably not higher than 480 ° C (preferably by passing a heated non-boiling steam through the contents of the drum) for a period of time which gives a coke having a volatile combustible content of at least 4%, preferably at least 5% and not more than 10%, preferably not more than 8% by weight. The time required for the production of coke with such a content of volatile combustible material after decoupling of the coke drum varies with the coke produced, and the starting material used for the production of this coke and the heating temperature, but in most cases such a reduction can be effected by heating the relaxed coke drum for a period of time of the order of 4 to 24 hours.

The subsequent off-stream heating of the contents of the coke drum is accomplished using a non-boiling steam. Any of a wide variety of materials not suitable for the production of coke can be used for this heating and representative examples of suitable materials which may be mentioned are light coke distillates, coke gases (C1-C4 hydrocarbons), water vapor, nitrogen and other non-coke boiling gases with the exception of gases which are oxidizing gases. The choice of a suitable gas to effect the heating is within the skill of the artisan. In some cases it may be possible to achieve this heating by other means than passing a heated gas through the contents of the coke drum, but for most commercial operations the preferred and most practical way of heating the contents of the coke drum is to use superheated vapors.

In some cases the heating of the contents of the coke drum can be effected with a material which can form coke, such as a heated coke recycle or coke return material plus relatively low concentrations of coke starting material, but in most cases the quality of the coke produced with use of such materials lower than the quality produced using a non-coking material.

Thus, according to the present invention, the delayed coking is carried out at a temperature lower than that normally used in this field of the art until the coke drum is filled to the desired level, and then the coking drum is removed; u is taken (taken off-stream), its contents are heated to a higher temperature to bring about a reduction in the content É of volatile combustible material therein. The combination gives 454 701 4 an end product, which on calcination receives a reduced coefficient of thermal expansion. The specific temperatures used in each of the coking steps and subsequent heating after relaxation vary with the particular starting material as well as with the desired coefficient of thermal expansion of the final product. In general, it has been found that the use of lower temperatures in the above general range of coking temperatures gives a final product with a lower coefficient of thermal expansion, but with some starting materials higher temperatures in the general range of processing temperatures described above are required to achieve an appropriate reaction rate.

As stated above, the present invention is particularly applicable to the production of highly crystalline coke (needle coke) and in particular to the production of highly crystalline petroleum coke starting from a petroleum feedstock which has been pretreated in the manner set forth in U.S. Pat. 4,108,798 or 4,199,434.

According to the general method of the invention, the starting material is first kept warm in the presence of sulfur, followed by heating the heat-treated starting material in this way to a higher temperature to produce controlled thermal cracking, which improves the aromaticity of the starting material. The material obtained from the thermal cracking is then treated to separate non-crystalline material from the material, followed by heating the coking starting material, which is free of non-crystalline substances, in a coking heating device to provide a boiling point temperature of the order of from 415 to 455 ° C, and after the coke drum has been decoupled, its contents are heated to a temperature which is at least 10 ° C higher than the coking temperature and which temperature is from 450 to 50 ° C, without a rhyme sufficient to reduce the content of volatile combustible material therein to a value specified above. The starting materials commonly used for the production of coke according to the invention are heavy petroleum starting materials, such as a distillation residue obtained from crude oil, lube oil extract and hydrodesulfurized lubricating oil extracts, a cracking residue or a hydrodesilation or cracking of petroleum. Preferred starting materials are so-called pyrolysis fuel oils or black oils, which are the remaining heavy black oils that boil over pyrolysis gasoline, ie. boiling above 187 to 188 ° C and which are prepared together with olefins by pyrolysis of liquid hydrocarbon feedstocks, catalytic cracking decanting oils, thermally cracked tar, lubricating oil extracts and hydrodesulfurized products thereof, carbon tar or pitch distillate and the like. In general, such starting materials have a low sulfur content, ie. sulfur content of 1.5% by weight or less, preferably 0.8% by weight or less. Mixtures of such starting materials can be used.

The starting material is first heat treated in the presence of at least 30 million parts of sulfur, this sulfur being preferably added by the addition of sulfur (generally in the form of at least one substance selected from the group consisting of elemental sulfur, mercaptan and carbon disulfide). In most cases, the amount of sulfur added does not exceed 200 ppm. The soaking is generally carried out for at least 5 minutes and in particular from 5 to 120 minutes. The through-heating temperature is generally of the order of 230 to 315 ° C. If the required amount of sulfur is present in the starting material, no sulfur needs to be added to it. In some cases it is possible to achieve the desired results by heating at a temperature of from 230 to 35 ° C without the use of sulfur. It is believed that the heating step improves the overall effect of polymerizing polymerizable components.

The thoroughly heated starting material is then heat treated to effect controlled thermal cracking thereof to thereby increase the aromaticity (decrease the API gravity). The heat treatment to effect cracking, which follows the initial thermal heating, is carried out by heating the starting material, generally in a tubular heating device, under a pressure of the order of 4 to 50 kp / cm 2 (overpressure) to an outlet temperature. of the order of 450 to 595 ° C.

The cracking is effected for a period of time, which increases the aromaticity, this cracking generally being of the order of 15 to 120 seconds. In general, the API density increases by at least 1 ° (based on materials boiling above 260 ° C).

After the heat treatment, the starting material can be treated to remove non-crystalline substances and non-distillable heavy components, this separation being generally easily accomplished by using high temperature flash evaporation, this rapid evaporation generally being carried out at a temperature of 380 to 105 ° C under a pressure of from 0.1 kp / cm2 (absolute) to 2 kp / cm2 (gauge pressure). In the rapid evaporation, the non-crystalline substances can be selectively removed as pitch bottom products. The material recovered as a boiling starting material generally boils in the range of 260 to 538 ° C. Lighter components from the starting material, such as gas, petrol and gas oil, can be recovered separately.

The coking starting material pretreated, as described above, is then subjected to delayed coking by the general method known in the art, except that according to the present invention it has been found that the coking temperature should be controlled to temperatures lower than those generally used in the technique. The optimum coking temperature varies with each starting material. The coking pressure is generally of the order of 2 to 2 kp / cm (gauge pressure).

After filling the coke drum, the drum is disconnected from the stream and the contents are heated to a temperature which is at least 454 701 7 10 ° C higher than the coking temperature and which temperature is from 450 to 500 ° C, for a period of time sufficient to lower the volatile content. combustible material to the values given above. Although the embodiment described above is particularly preferred, it is a given that one or more of the steps for pretreatment of the starting material can be eliminated, whereby the coking method according to the invention also in such cases gives an improvement of the quality of the coke, although in most cases the combination of the three pre-treatment steps, in combination with the use of controlled outlet temperatures in the coke heater and subsequent heating after off-stream to reduce the content of volatile combustible material, produces coke of the highest quality. Thus, for example, the initial heating may be eliminated and / or the cleavage of the starting material may be eliminated and / or the separation of non-crystalline components may be eliminated within the scope of the invention, provided that the coking heating device is operated at the foregoing temperatures and its contents are heat treated. after off-stream, as described above, to produce a coke having the volatility described above.

For example, U.S. Patent No. 4,199,434 discloses pretreatment of a boiling starting material by combining heating at a first temperature in the presence of sulfur, followed by heating to a higher temperature to lower the API weight (gravity). U.S. Pat. No. 3,687,840 discloses the pretreatment of a boiling starting material in the presence of sulfur.

The invention is further described in connection with an embodiment thereof, which is illustrated in the accompanying drawing figure.

The drawing is a simplified schematic representation of a 454 701 8 flow chart for carrying out the method according to the invention.

As shown in the drawing, a starting material is introduced through a conduit 10 into a heating drum designated 12 and sulfur is introduced, if required, into the drum 12 through a conduit 13.

In the drum 12, the starting material is heated as described above, this heating heating causes polymerization of strongly unsaturated compounds.

The heated starting material is taken from the drum 12 through a conduit 14 and inserted into a pipe loop 15 in a thermal cracking heater 16, in which the starting material is subjected to thermal cracking conditions, as described above, to increase the total aromaticity in the material ( of the API weight). The cracked starting material is taken out of the loop 15 through a line 17, quenched with light gas oil, obtained as described above, through a line 18, and the combined streams are passed through a pressure relief valve 19 into a vacuum rapid evaporation tower, as schematically denoted 21. The vacuum rapid evaporator tower is operated at a temperature and pressure which provides separation from the starting material of non-crystalline substances and other heavy components. In general, the rapid evaporation tower is operated at a temperature of the order of 380 to 510 ° C and a pressure of the order of 0.1 kp / cm 2 absolute to 2 kp / cm 2 overpressure.

A heavy pitch-like bottom product is recovered from the tower 21 through a conduit 22. A light gas oil is recovered from the tower 21 through a conduit 23 and a portion thereof is used through a conduit 18 as a rapid cooling oil. Naphtha and lighter gases are recovered from the rapid evaporation tower through a line 24.

The pretreated coking feedstock, which is collected through a line 25, is generally those components which are in the boiling temperature range of the order of 268 to 538 ° C and these components are introduced into a coking PP 454 701 I 9 fractionator combination tower, which schematically is displayed with 27.

The coking-fractionator combination tower 27 is operated, as is well known to those skilled in the art, for recovering the bottom products of the coking starting material and also for recovering lighter components which are generally not used in the coking starting material, such as a heavy coking gas oil through a line 28. a light coking gas oil through a line 29 and coking naphtha and gases through a line 31.

As is known to those skilled in the art, the coke fractionation tower 27 is also supplied with coke drum overhead vapors leaving a line 32.

Bottom products discharged from the tower 27 through a conduit 34 are passed through a coking heater of a type known in the art, schematically generally designated 35, and the heated material is introduced into a coking drum, schematically designated 36. The coking drum is operated at the temperatures and pressures indicated above. Transient vapors are discharged from the coke drum 36 through a line 38 and after quenching with a portion of the light gas oil in a line 39, these transient vapors are introduced into the coke fractionator 27 through the line 32.

After the coke drum has been filled, as is known in the art, the coke drum is disconnected, ie. the drum is no longer supplied with coking starting material. The relaxed drum is designated 36 'in the figure.

According to the present invention, the decoupled drum 36 'is heated to a higher temperature to reduce the amount of volatile combustible material therein and to lower the coefficient of thermal expansion. As shown in the drawing, superheated gas, such as light coke distillate, naphtha, coking gas, etc., is introduced into the coke drum 36 'through a line 101, this gas generally having a temperature and pressure sufficient to maintain the decoupled drum 36'. at the above temperatures for lowering the content of volatile combustible constituents. Generally, the steam is introduced at a temperature of the order of 450 to 525 ° C and a pressure of the order of 2 to 10 kp / cm 2 overpressure. The steam is introduced through a conduit 101 and together with volatile material which is evaporated from the contents of the drum, the steam from the decoupled coke drum 36 'is discharged through a conduit 102 and introduced into a rapid cooling tower designated 103, which is designed and operated to recover non-boiling steam be used in the relaxed drum 36 '. In the quenching tower 103, lighter components are recovered through a conduit 104, such as a gas, the material to be used as a drying gas is recovered through a conduit 105, such as a liquid, and heavier components are recovered through a conduit 106. Some of the material in the conduit The conduit 105 is passed through a conduit 107, including a cooler 108, for insertion into the tower 103 through a conduit 109 as reflux. The remaining part of the conduit 111 is heated in the evaporator 112 to provide evaporation for use as a drying gas. The heated material from the heater 112 is introduced into a separator 115 for separating undifferentiated material, which is removed through a conduit 116. Superheated steam is discharged from the separator 115 through a conduit 101 for insertion into the disconnected drum to provide a coke with a content of volatile combustible material, as described above.

According to a modification, the steam for the drying step can be recovered from the coking combination tower and the material taken from the decoupled drum is returned to the coking combination tower. Thus, in this operation, the coking combination tower is used for both the "on-line" and "off-line" coke drums, although the preferred embodiment has been described in connection with pretreatment of the starting material by (1 ) heating at low temperature to polymerize unsaturated components, (2) thermal cracking to increase the content of aromatic constituents (reduction of the API weight) and (3) separation of pitch, the invention is also applicable to coke m * '- - ''> -. - _. - ..._..__-..-_.: -_ - ..-. E.; '.... J fl ïüí * “i 5 454 701 ll production without such pre-treatment and coke production, which utilizes one or more such pre-treatment steps.

The invention is further described by the following examples.

Example 1.

Decanting oils with the properties summarized in Table I were added with 50 million parts of sulfur and heated through at a temperature of 260 ° C. The starting material treated in this way was introduced into a tube with an inner diameter of 6 mm and thermally cracked at a temperature of 500 ° C under a pressure of 20 kp / cm 2 overpressure. (The residence time was 78 seconds on a cold oil basis). The starting material was then introduced into a rapid evaporation tower maintained at 48 ° C under normal pressure and non-volatiles were removed from the bottom of the rapid evaporation tower such as pitch. The oil obtained by cooling the rising effluent was used as a starting material for coking.

Table I.

Density, 1s ° / 4 ° c 1, oss7 API weight 7.4 Asphaltenes (C7 insoluble) 1.6% by weight Conradson carbon 5.71% by weight Sulfur content 0.75% by weight Ash 0.01% by weight Delayed coking was carried out during the Table II showed the conditions using the oil obtained under the above conditions. The coke drum, which had an inner diameter of about 30 cm and a height of about 50 cm, was placed in a bath of molten salt and was designed to allow external heating. After the drum was filled, the drum was relaxed and heated, as indicated in the table. <4 .mmcw mmvuwsmmø> m mn fl nø fl m> cm cmu fl u fi mm u fi mëm> m umn nam> m mc fl cU: m> cm mmä m flfi msuumummø nmnøumummäwummc fl cuuwzmmo ~ .v m.mm mm æu fl nmwm mmm uuam 2 u2m. ow «OH OH O_a vw vw vw mmm omw omv Owv mmm 454 701 N ~ æ æ_æ xucumuxm« u: nmuxm m fifi owmm m fi aowmm uum fl n uuw fi a lwmc fl nmxo fi Immc fl cmxom ß ß Owv Owm H WW M ~ U. a .w. Hm fl uwpma uumnnawun uu fl uxw fl m wxog nmuw mmcm wmubmnmma E. 92.

AOOV uøumummåma møcm flfl msnww amwomndumm t: nä. .xomuuHm> m Eo \ mxv N xuænü _00. udumnmmäma un xmmuwm A fi mmuumlumov fl mHmmOx> m _mc flfl uumSmmD Aammnumnmo. The experiments AC according to Table II were carried out by the process according to the invention, while the experiments D and E were carried out under other conditions: The temperature after relaxation in Experiment D was lower and the coking temperature in the switched-on state at Experiment E was higher than those used in the process of the invention. Green coke obtained under these conditions was calcined at 140 DEG C. by the usual method and the calcined coke was pulverized. Each sample of calcined coke was mixed with coal tar pitch as a binder and the mixture was extruded into rods to make electrodes. The electrodes were baked at 1000 ° C and graphitized at 3000 ° C. The coefficient of thermal expansion in the direction parallel to the extrusion was measured. The measurements obtained are shown in Table III.

Table III.

ABCDE ._ .- Coefficient of thermal expansion 0.79 0.74 0.89 1.31 1.21 (x10 5 / ° C) in the direction parallel to the strand spray (100-400 C) The green coke obtained in experiment D contained a variety of pitch-like substances in the upper part. It melted and fermented during the calcination and had a very bad appearance. The green coke obtained in Experiment E was porous and showed a large amount of foam.

As can be seen from Table III, the coke obtained by the process of the invention was of very high quality.

Example 2.

Decanting oils having the properties shown in Table IV were pretreated under the conditions summarized in Table V to give starting material for coking. 454 701 14 Table IV.

Density, 1s ° / 4 ° c 1,019: Asphaltenes (G7 insoluble) 3.7% by weight Conradson carbon 6.4% by weight Sulfur content 0.64% by weight Ash 0.01% by weight Table V.

Through- Amount of added sulfur 50 ppm Heating Temperature 270 ° C Residence time 15 minutes Cracking Pipe inner diameter 6 mm Outlet temperature 490 ° C Pressure 22 kp / cmz overpressure Residence time 78 seconds Rapid temperature 480 ° C evaporation Pressure atm The material balance during pre-treatment is shown in Table VI.

Table VI.

Beck ll, 1% by weight Coking starting material (290 ° C +) 84.3% by weight Distillate (290 ° C ') 2.4% by weight Cracked gas and loss 2.2% by weight Coking was carried out on the starting materials obtained in this way under the conditions set out in Table VII and the content of volatile combustible material of the green coke thus obtained is also shown in the same table. 454 701 15 Table VII.

Experiment No. ,, I. EQ g I Delayed Temperature ° C 435 440 447 430 kk '2 H iâkâgšïgá Pressure (kp / cm overpressure) 5 5 5 5 (on-stream) Time (h) 24 24 24 24 Return goods quantity- 0, 6 0.6 0.6 0.6 ratio QI in the cooking drum 3 3 4 4 heating, Temperature ° c 460 460 447 430 relaxed. (° ff_stream) Time (h) 6 6 6 6 Heated steam STM STM STM STM Green coke 6.2 5.8 ll, 7 23.6 Volatile combustible material (weight percent) Experiments F and G were carried out using the procedure according to the invention, while experiment H was carried out at a higher coking temperature with the cooking drum switched on (stream) than according to the invention and test I at a lower heating temperature decoupled (off-stream) than according to the invention.

Electrodes were made of coke obtained under the conditions set forth in Table VII and graphitized at 3000 ° C. Coefficient of thermal expansion and MR value for graphitized electrodes are shown in Table VIII.

Table VIII.

Experiment No. E § g I Coefficient of thermal expansion 0.86 1.00 1.17 1.33 (x10 "5 / ° C) in the direction parallel to the strand spray (100-400 C) As shown in Table VIII, the coke obtained had 454,701 Exemgel 3. Pyrolysis star obtained as a by-product in thermal cracking of gas oil was pretreated under the conditions summarized in Table IX and coke was prepared from the coking starting material thus refined.

Heating Cracking Rapid evaporation Table IX.

Amount of sulfur added Temperature Residence time Pipe inner diameter Outlet temperature Pressure Residence time (based on cold oil) Temperature Pressure 100 ppm 2so ° c 20 minutes 6 mm 47o ° c 25 kp / cmz overpressure 62 seconds 46o ° c atm.

Coking was performed on this coking starting material under the conditions set forth in Table X.

Attempt no- Delayed coking, on-stream Heating, Temperature (OC) off-stream Green coke Table X.

E Temperature (° C) 435 Pressure 2 6.5 (kp / cm overpressure) Time (h) 24 Returned goods 1.0 quantity ratio 460 Time (h) 8 Heated Coke steam-- distillate I 6.7 Volatile combustible material (weight percent) EE ä 460 440 445 6.5 6.5 6.5 24 24 24 1.0 1.0 1.0 460 460 460 8 8 0 8 None Light Light (external) coke coke Experiment J was carried out by the method according to the invention, while Experiment K was carried out at a higher coking temperature with the drum switched on than in Experiment J. The electrodes were prepared. of coke in the same manner as in Example 1 and the coefficient of thermal expansion of electrodes graphitized at 3000 ° C was measured. The results of the measurements are shown in Table XI.

Table XI.

Experiment No. 1 § Q Q Coefficient of thermal expansion 0.73 1.38 0.87 0.99 (x10 / ° C) in the direction parallel to the straw spray (100-400 C) Example gel 4.

Hydrodesulfurized decanting oil having the properties shown in Table XII was pretreated under the same conditions as shown in Table V according to Example 2 to obtain a coking starting material.

Table XII.

Density, 1s ° / 4 ° c 1, o142 Asphaltenes (C7 insoluble) 0.2% by weight Conradson carbon 2.6% by weight Sulfur content 0.52% by weight Ash 0.01% by weight The coking was carried out on this coking starting material under the conditions compiled in Table XIII and the content of volatile carbonaceous material of the green coke thus obtained are shown in the same table. 454 701 18 Table XIII. i Test No. 7 g Q 2 Driver 'Temperature (° c) 445 4ss 465 _, ._ coking 9 "connected ïíyïk 2 rk 6'5 6'5 5'5" * - (° n_stream) p cm overpressure) Time ( h) 24 24 24 Returned goods 1.0 1.0 1.0 quantity ratio Heating, Temperature (OC) 4654 455 465 relaxed. (off-stream) Tld (h) 6 2 6 Heated steam Coking- Steam Coking- -light -light-distillate distillate Green coke 7.8 12.5 5.2 Volatile carbonaceous material (%) Experiment N was carried out by the process according to the invention, while test P was carried out at a higher coking temperature with the drum switched on than according to the invention. Experiment 0 was performed at a coking temperature with the drum switched on at 455 ° C and then, after filling the drum, the contents of the drum were purged with unheated steam for 2 hours without using a temperature higher than the coking temperature. Electrodes were made of coke obtained under the conditions compiled in Table XIII and graphitized at 300,000. The thermal expansion values of graphitized electrodes are shown in Table XIV.

Table XIV.

Experiment No. g Q 2 Coefficient of thermal expansion in 0,83 1,22 1,19 the direction parallel to compression O (100 ~ 400 C) 1. » As can be seen from Table XIV, coke obtained by the process of the invention (Experiment N) was of very high quality.

The invention is particularly advantageous in that it utilizes the combination of delayed coking at a lower temperature than. J 454 701 19 the one normally used in the art, followed by heating the contents of the coke drum with the drum discharged (off-stream) at a higher temperature to produce a coke having a specified content of volatile combustible materials, the coke being produced in this way (after calcination and graphitization) has a lower coefficient of thermal expansion. If the coke is produced at the lower temperature, followed by calcination and graphitization (no heating after relaxation in the coke drum at a controlled temperature to give a content of volatile combustible material as described above before the calcination), the coefficient of thermal expansion of the graphitized coke will be higher than that obtained according to the invention.

The invention is, as described above, particularly applicable to the production of needle coke (coefficient of thermal expansion as well as super-needle coke with coefficient of thermal expansion <1.1 x 10 6 "/ 6 / ° c measured at 10 -4 ° C).

The invention is also particularly applicable to the coking of a feedstock, which has been pretreated by (1) thermal heating at 230-315 ° C, generally in the presence of sulfur (although in some cases sulfur is not required) to reduce the tendency to deposit of coke and / or polymers in subsequent conduits or equipment and / or (2) thermal cracking at 450-59500 to increase the aromaticity and / or (3) separation of non-crystalline substances. Although pretreatment is not required and / or pretreatment using only one or two of the pretreatment steps can be used, the best results (lowest coefficient of thermal expansion) are generally obtained by using the three pretreatment steps in combination with coking at controlled temperatures, followed by heating. after off-stream to reduce the content of volatile combustible constituents.

Claims (10)

. . __... -._..._ .. ».._-. J 454 701 20 PATENTKRAV A method for delayed coking of a coking starting material, wherein the coking starting material is heated in a coking heating device and inserted into a coking drum and the coking drum after filling to the desired level is disconnected by interrupting the insertion of the coking starting material, that the starting material in the coke drum is coked at a temperature of from 415 to 455 ° C before decoupling the coke drum and that after decoupling the coke drum the contents of the decoupled coke drum are heated at a temperature which is at least 10 ° C higher than previous coke and amounts to from 450 to 500 ° C until the coke has a volatile combustible content of at least 4% and not more than 10% by weight. 2. A process according to claim 1, characterized in that the heating temperature is at least 15 ° C higher than the temperature at the previous coking. 3. A process according to claim 1 or 2, characterized in that the coking temperature is from 420 to 450 ° C. 4. A method according to any one of the preceding claims, characterized in that the heating temperature is at least 460 and at most 480 ° C. 5. A method according to any one of the preceding claims, characterized in that the decoupled coke drum is heated by passing a heated non-boiling steam through its contents. 6. A method according to any one of the preceding claims, characterized in that the boiling starting material is pretreated by heating at a new temperature; From 230 to 315 ° C for polymerizing unsaturated constituents in the starting material. Process according to Claim 6, characterized in that the heating is carried out in the presence of at least 30 ppm of dissolved sulfur. 8. A method according to any one of the preceding claims, characterized in that the starting material is pretreated by heating to effect thermal cracking at a final temperature of from 450 to 595 ° C. Process according to one of Claims 1 to 5 or 7, characterized in that heating the starting material at a temperature of from 230 to 315 ° C to polymerize unsaturated constituents heats the heated heating starting material to provide by thermal cracking thereof at a final temperature of from 450 to 59 ° C and separating non-crystalline substances and heavy components to obtain a pitch-free starting material. 10. A process according to any one of the preceding claims, characterized in that the starting material is pyrolysis fuel oil, lubricating oil extract or hydrodesulfurized lubricating oil extract, catalytic cracking decanting oil, thermally cracked tar or a mixture thereof.