CA2041339A1 - Technique for reducing vcm coking - Google Patents
Technique for reducing vcm cokingInfo
- Publication number
- CA2041339A1 CA2041339A1 CA002041339A CA2041339A CA2041339A1 CA 2041339 A1 CA2041339 A1 CA 2041339A1 CA 002041339 A CA002041339 A CA 002041339A CA 2041339 A CA2041339 A CA 2041339A CA 2041339 A1 CA2041339 A1 CA 2041339A1
- Authority
- CA
- Canada
- Prior art keywords
- light hydrocarbon
- coke
- hydrocarbon stream
- drum
- vcm
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
- C10B57/00—Other carbonising or coking processes; Features of destructive distillation processes in general
- C10B57/005—After-treatment of coke, e.g. calcination desulfurization
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
- C10B55/00—Coking mineral oils, bitumen, tar, and the like or mixtures thereof with solid carbonaceous material
Abstract
ABSTRACT OF THE DISCLOSURE
A process for producing superior grade coke in a coking drum is accomplished by stripping increased amounts of volatile carbonaceous material using a light hydrocarbon stream without sacrificing cycle time.
The light hydrocarbon stream is effective in solubilizing the volatile carbonaceous material while cooling the formed coke.
A process for producing superior grade coke in a coking drum is accomplished by stripping increased amounts of volatile carbonaceous material using a light hydrocarbon stream without sacrificing cycle time.
The light hydrocarbon stream is effective in solubilizing the volatile carbonaceous material while cooling the formed coke.
Description
3 ~ 9 THE SPECIFICATION
NOVEL TECHNIQUE FOR REDUCING VCH COKING
BACKGROUND OF THE INVENTION
.
The present invention relates to an improved process for forming coke with a low volatile carbonaceous matter content.
Processes for forming coke from petroleum hydrocarbons are well-. ~. .
known. See, for example, U.S. Patent Nos. 3,745,110 and 3,836,434; the S disclosures of which are incorporated herein by reference. Such processes involve heating certain petroleum hydrocarbon streams to elevated temperatures, for example 925-975F, and rapidly running the hot hydrocarbons into the bottom of a relatively quiescent chamber known as a coking drum. As the hydrocarbons are charged into the coking drum, they 10 undergo coking, i.e., they undergo a chemical change ~rom a liquid to a solid.
When charging of the coking drum with petroleum hydrocarbons is completed, ie is customary to introduce steam into the bottom of the coking drum. This procedure, which is referred to as steam stripping, 15 drives off non-coked hydrocarbons, i.e., portions of the hydrocarbon feed which have not become a carbonaceous solid. In addition, steam stripping provides initial cooling of the very hot mass of coke in the coking drum.
After steam stripping, the coke is further cooled to a relatively low temperature of about 200F or less so that it can be safely removed from 20 the coking drum. The cooling is accomplished by charging steam and water into the bottom of the coking drum. Care must be taken to adjust the water flow rate during water cooling to prevent high pressures from developing at the coke drum inlet.
3 3 ~
When th~ water coolin~ operation is completed, the coking drum is ready for emptying. This is accomplished by removing covering plates called heads, located at the top and bottom of the cok;ng drum and breaking the hardened coke into chunks. Break-up of the coke is normally 5 accomplished by means of high pressure water drills which direct jets of high pressure water into the coke. The chunks of coke so formed fall throu~h the bottom of the coking drum to railcars or other suitable means of transportation.
As an alternative to steam stripping, U.S. Pat. No. 4,547,284 lO discloses that a portion of the VCM can be converted to coke by passing a heated non-coking vapor through the contents of the drum after the coker drum has been taken off stream, i.e., the residuum feed has been switched to the other coke drum. The non-coking vapor is introduced at a temperature above the coke temperature to increase the coke temperature 15 and facilitate reacting of the VCM. This requires additional energy input and increases cycle time, thereby decreasing the productivity of the coker.
Generally, coke buyers prefer coke with a low, consistent volatile carbonaceous matter (VCM) content. However, "green" coke, as it 20 is removed from the coking drums, usually contains high amounts of tar-like VC~. VCM is especially high in the coke found in the upper portion of the coke drum which has experienced the shortest reaction time.
Customarily, this "green" coke is subjected to calcination at elevated temperatures to reduce the VCM and produce a finished petroleum coke.
25 E~owever, coke with a high VCH content often undergoes undesirable "popcorning" i.e., sudden expansion when subjected to higher calcination temperatures.
Accordingly, it is an object of the present invention to provide an improved method for preparing "green" coke with a low volatile 30 carbonaceous matter content without increasing cycle time or furnace fuel demand.
SUMMARY OE THE INVENTION
It is a primary objective of this invention to provide an efficient process for the production of coke having a reduced VCM content.
3 3 ~
Additional objects and advantages of this invention will be obvious from the description, examples, and appended claims.
The foregoing objective is accomplished by carrying out the coking of a petroleum hydrocarbon stream in a coking drum. Generally, the 5 hydrocarbon is a high boiling petroleum residuum.
The high boiling petroleum hydrocarbon residuum is heated and introduced as a feedstock to a coke drum to form coke and overhead vapors.
The overhead vapors escape through the top of the coke drum and are passed to a bubble tower. After the drum is filled with porous solid coke, a 10 liquid light hydrocarbon stream is introduced into the bottom of the coking drum at a temperature below that of the coke in the drum. The light hydrocarbon stream functions to reduce the volatile carbonaceous material in the coke as it passes through the drum. The light hydrocarbon stream extracts a portion of the VCM and the mixture passes through the 15 coking drum to an overhead outlet and subsequently to the bubble tower.
Following the introduction of the light hydrocarbon stream, the coke can be optionally steam stripped or stripped with an inert stream. Finally, the coke is water quenched and cut as is known in the art.
A superior grade coke is obtained because the VCM content of the 20 coke is reduced below the level typically achieved with steam stripping alone. In addition, the VCM remaining in the coke is more uniformly dispersed throughout the coke, i.e., the coke at the top of the drum is more similar in VCM content to the coke at the bottom of the drum. The light hydrocarbon stream, also functions to reduce the coke temperature, 25 therefore cycle time is not increased.
The advantages of this process arise because the light hydrocarbon stream is readily available at refineries and has a much greater affinity for the tar-like VCM found in the coke than does steam.
Accordingly, greater amounts of VCM are removed from the coke and cooling 30 of the coke is still effectively accomplished. In addition, the remaining VCM is more consistently distributed. Another advantage is that bubble tower operation is more stable because the thermal upset caused by steam is avoided. Furthermore, overall cycle time is not extended by injecting a heated light hydrocarbon vapor to raise coke drum temperature. In fact, 35 introduction of a liquid light hydrocarbon stream cools the coke more effectively than steam stripping. This occurs because the liquid light hydrocarbon stream removes heat from the coke bed during its vaporization.
NOVEL TECHNIQUE FOR REDUCING VCH COKING
BACKGROUND OF THE INVENTION
.
The present invention relates to an improved process for forming coke with a low volatile carbonaceous matter content.
Processes for forming coke from petroleum hydrocarbons are well-. ~. .
known. See, for example, U.S. Patent Nos. 3,745,110 and 3,836,434; the S disclosures of which are incorporated herein by reference. Such processes involve heating certain petroleum hydrocarbon streams to elevated temperatures, for example 925-975F, and rapidly running the hot hydrocarbons into the bottom of a relatively quiescent chamber known as a coking drum. As the hydrocarbons are charged into the coking drum, they 10 undergo coking, i.e., they undergo a chemical change ~rom a liquid to a solid.
When charging of the coking drum with petroleum hydrocarbons is completed, ie is customary to introduce steam into the bottom of the coking drum. This procedure, which is referred to as steam stripping, 15 drives off non-coked hydrocarbons, i.e., portions of the hydrocarbon feed which have not become a carbonaceous solid. In addition, steam stripping provides initial cooling of the very hot mass of coke in the coking drum.
After steam stripping, the coke is further cooled to a relatively low temperature of about 200F or less so that it can be safely removed from 20 the coking drum. The cooling is accomplished by charging steam and water into the bottom of the coking drum. Care must be taken to adjust the water flow rate during water cooling to prevent high pressures from developing at the coke drum inlet.
3 3 ~
When th~ water coolin~ operation is completed, the coking drum is ready for emptying. This is accomplished by removing covering plates called heads, located at the top and bottom of the cok;ng drum and breaking the hardened coke into chunks. Break-up of the coke is normally 5 accomplished by means of high pressure water drills which direct jets of high pressure water into the coke. The chunks of coke so formed fall throu~h the bottom of the coking drum to railcars or other suitable means of transportation.
As an alternative to steam stripping, U.S. Pat. No. 4,547,284 lO discloses that a portion of the VCM can be converted to coke by passing a heated non-coking vapor through the contents of the drum after the coker drum has been taken off stream, i.e., the residuum feed has been switched to the other coke drum. The non-coking vapor is introduced at a temperature above the coke temperature to increase the coke temperature 15 and facilitate reacting of the VCM. This requires additional energy input and increases cycle time, thereby decreasing the productivity of the coker.
Generally, coke buyers prefer coke with a low, consistent volatile carbonaceous matter (VCM) content. However, "green" coke, as it 20 is removed from the coking drums, usually contains high amounts of tar-like VC~. VCM is especially high in the coke found in the upper portion of the coke drum which has experienced the shortest reaction time.
Customarily, this "green" coke is subjected to calcination at elevated temperatures to reduce the VCM and produce a finished petroleum coke.
25 E~owever, coke with a high VCH content often undergoes undesirable "popcorning" i.e., sudden expansion when subjected to higher calcination temperatures.
Accordingly, it is an object of the present invention to provide an improved method for preparing "green" coke with a low volatile 30 carbonaceous matter content without increasing cycle time or furnace fuel demand.
SUMMARY OE THE INVENTION
It is a primary objective of this invention to provide an efficient process for the production of coke having a reduced VCM content.
3 3 ~
Additional objects and advantages of this invention will be obvious from the description, examples, and appended claims.
The foregoing objective is accomplished by carrying out the coking of a petroleum hydrocarbon stream in a coking drum. Generally, the 5 hydrocarbon is a high boiling petroleum residuum.
The high boiling petroleum hydrocarbon residuum is heated and introduced as a feedstock to a coke drum to form coke and overhead vapors.
The overhead vapors escape through the top of the coke drum and are passed to a bubble tower. After the drum is filled with porous solid coke, a 10 liquid light hydrocarbon stream is introduced into the bottom of the coking drum at a temperature below that of the coke in the drum. The light hydrocarbon stream functions to reduce the volatile carbonaceous material in the coke as it passes through the drum. The light hydrocarbon stream extracts a portion of the VCM and the mixture passes through the 15 coking drum to an overhead outlet and subsequently to the bubble tower.
Following the introduction of the light hydrocarbon stream, the coke can be optionally steam stripped or stripped with an inert stream. Finally, the coke is water quenched and cut as is known in the art.
A superior grade coke is obtained because the VCM content of the 20 coke is reduced below the level typically achieved with steam stripping alone. In addition, the VCM remaining in the coke is more uniformly dispersed throughout the coke, i.e., the coke at the top of the drum is more similar in VCM content to the coke at the bottom of the drum. The light hydrocarbon stream, also functions to reduce the coke temperature, 25 therefore cycle time is not increased.
The advantages of this process arise because the light hydrocarbon stream is readily available at refineries and has a much greater affinity for the tar-like VCM found in the coke than does steam.
Accordingly, greater amounts of VCM are removed from the coke and cooling 30 of the coke is still effectively accomplished. In addition, the remaining VCM is more consistently distributed. Another advantage is that bubble tower operation is more stable because the thermal upset caused by steam is avoided. Furthermore, overall cycle time is not extended by injecting a heated light hydrocarbon vapor to raise coke drum temperature. In fact, 35 introduction of a liquid light hydrocarbon stream cools the coke more effectively than steam stripping. This occurs because the liquid light hydrocarbon stream removes heat from the coke bed during its vaporization.
2~33~
SAM-P-~3901 Page 4 DESCRIPTION OF THE DRAWINGS
The figure described below is a simplified schematic representation of a flow diagram for effecting the process of the present invention, wherein, superior grade coke is produced.
DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to a preferred embodiment of the present invention. While the inventive process will be described 15 in connection with a preerred procedure, it will be understood that it is not intended to limit the invention to that procedure. On the contrary it is intended to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the invention defined by the appended claims.
Referring now to Figure 1, a feed which is generally a petroleum residuum, e.g., crude oil vacuum bottoms, is fed through line 1 to bubble tower 3 where it is stripped. The coke drum overhead vapors entering through line 11 provide the heat for fractionation. The resultant tower bottoms consisting of condensed recycle from the coking operation and all 25 but the low boiling fractions of the regular coker feed is passed through line 5 to the fired heater 7. The coker charge is heated to a temperature sufficient to produce the coking reaction and is passed through line 8 into one of the coke drums 9A or 9B. One of the coking drums is "on-line"
being filled while the second drum is "off-line" being stripped, cooled, 30 and emptied. Access to the drums is controlled by valves 12A and 12B.
Overhead vapors from the coke drums exit via line 11 and return to the bubble tower 3.
In general, following the drum filling cycle, the bottom of the coke drum is much hotter than the top of the drum, for example about 35 900F, and about 825F respectively. In the process of the prior art, steam is introduced into the hottom of the drum at about 350F. The steam cools the hot coke bed and s~eeps some VCM out of the bed through an overhead vapor outlet leading to a bubble tower. ~hile the steam is being . .
' :
2 ~ 3 ~
introduced, a second drum is placed "on-line" to receive the coker feedstock. Since the second coke drum is relatively cool and empty, the quantity of vapors exiting the top is much lower than the steady state value. This decrease in the amount of hot vapor entering the bubble tower 5 upsets the heat balance and decreases the effectiveness of the bubble tower.
According to the present invention, at the point of the cycle where steam is normally introduced, a light hydrocarbon stream is introduced as an alternative, or in conjunction ~ith steam. In the 10 process of the present invention, the light hydrocarbon vill be comprised of at least hydrogen and carbon. Furthermore, the light hydrocarbon stream is comprised largely of C3 to C30 hydrocarbon molecules.
Preferably, the stream consists largely of Cs to C20 hydrocarbon molecules. Due to its higher vapor density, greater weights per period of lS time of light hydrocarbon can be passed through the drum than steam, further facilitating VCM removal. The light hydrocarbon stream should be introduced at a temperature lower than the coke temperature in the drum.
Furthermore, the light hydrocarbon stream should be introduced at a temperature below its boiling range, i.e., substantially as a liquid at 20 coke drum inlet pressure. Any hydrocarbon stream with a boiling range below the coke temperature can be used. Preferably, the light hydrocarbon has a final boiling point less than about 900F. More preferably, the final boilin~ point is less than about 600F. Blends of light hydrocarbons and/or steam are also envisioned. Preferably, the light 25 hydrocarbon stream has a limited coking potential. The preferred light hydrocarbons are naphtha, kerosene, or light gas oil. More preferably, the light hydrocarbon is naptha or kerosene.
With regard to Figure 1, kerosene is introduced through line 13.
Valves lOA and lOB direct flow into the filled "off-line" drum. The 30 kerosene is introduced at a temperature below its boiling point.
Preferably the kerosene is below about 450F. Therefore, the kerosene serves to extract heat from the coke as did steam in the prior art process. Accordingly, cycle time is not increased. In fact, better heat removal within the coke drum is achieved with light hydrocarbons rather 35 than steam due to the energy necessary for the vaporization of the light hydrocarbon stream. Accordingly, the kerosene transfers more heat from the lower portion of the coke drum to the upper portion of the coke drum, 2~ 339 thereby increasing the coking activity of the top portion which has been subjected to coking reaction temperatures for the shortest period of time.
In addition, the kerosene has a higher affinity for the tar-like VCM than steam and will effectively strip this material from the product 5 coke by extracting the VCM into the gas phase. Without being bound by theory, it is also believed that the light hydrocarbons, because they are very soluble in the VCM, cause swelling of the VCM resulting in VCM being pushed out of micro-pores and into the macro-pores and ~ channels increasing the accessibility of the solvent flow. Furthermore, the light 10 hydrocarbon reduces the viscosity of the VCM, making it more mobile.
The hot light hydrocarbon routed back to the bubble tower through line 11, carrying the VCM will function to stabilize the thermal requirements of the colunln during the "on-line" swing from drum 9A to 9B.
As stated above, when a illed drum is taken "off-line", the next "on-15 line" drum initially produces less overhead heat and vapor. In addition,the light hydrocarbon is fully miscible with the bubble tower contents, in contrast to steam, therefore it does not negatively effect the bubble tower operation.
The VCM solubilized by the kerosene can be collected from the 20 bubble tower as usable hydrocarbons which is a significant economical advantage. The kerosene can be recovered in the bubble tower and recycled through line 13 to maintain the process.
Although stripping of the coke bed with a light hydrocarbon can eliminate the need for steam stripping, it is possible to accompany the 25 light hydrocarbon stripping ~ith steam stripping or to subsequently steam strip.
Lines 15, 17, 19 and 21 are the recovery lines for various product fractions from the bubble tower. The bubble tower aids recovery of products SUC}I as heavy coker gas oil (line 21), a light coker gas oil 30 (line 19), kerosene (line 13), naphtha (line 17) and gas (line 15).
The following example is illustrative of a specific comparison of stripping with a light hydrocarbon as opposed to inert solvents.
Example 1. Coke which had previously been steam stripped, resulting in a 13.1 weight percent VCM content, was treated in a 150 cc.
35 microreactor at 850F and a pressure of 25 p.s.i.g. with solvents consisting of nitrogen, coker naphtha, and coker kerosene. The light hydrocarbon solvents resulted in much greater reduction of coke VCM.
.
SAM-P-~3901 Page 4 DESCRIPTION OF THE DRAWINGS
The figure described below is a simplified schematic representation of a flow diagram for effecting the process of the present invention, wherein, superior grade coke is produced.
DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to a preferred embodiment of the present invention. While the inventive process will be described 15 in connection with a preerred procedure, it will be understood that it is not intended to limit the invention to that procedure. On the contrary it is intended to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the invention defined by the appended claims.
Referring now to Figure 1, a feed which is generally a petroleum residuum, e.g., crude oil vacuum bottoms, is fed through line 1 to bubble tower 3 where it is stripped. The coke drum overhead vapors entering through line 11 provide the heat for fractionation. The resultant tower bottoms consisting of condensed recycle from the coking operation and all 25 but the low boiling fractions of the regular coker feed is passed through line 5 to the fired heater 7. The coker charge is heated to a temperature sufficient to produce the coking reaction and is passed through line 8 into one of the coke drums 9A or 9B. One of the coking drums is "on-line"
being filled while the second drum is "off-line" being stripped, cooled, 30 and emptied. Access to the drums is controlled by valves 12A and 12B.
Overhead vapors from the coke drums exit via line 11 and return to the bubble tower 3.
In general, following the drum filling cycle, the bottom of the coke drum is much hotter than the top of the drum, for example about 35 900F, and about 825F respectively. In the process of the prior art, steam is introduced into the hottom of the drum at about 350F. The steam cools the hot coke bed and s~eeps some VCM out of the bed through an overhead vapor outlet leading to a bubble tower. ~hile the steam is being . .
' :
2 ~ 3 ~
introduced, a second drum is placed "on-line" to receive the coker feedstock. Since the second coke drum is relatively cool and empty, the quantity of vapors exiting the top is much lower than the steady state value. This decrease in the amount of hot vapor entering the bubble tower 5 upsets the heat balance and decreases the effectiveness of the bubble tower.
According to the present invention, at the point of the cycle where steam is normally introduced, a light hydrocarbon stream is introduced as an alternative, or in conjunction ~ith steam. In the 10 process of the present invention, the light hydrocarbon vill be comprised of at least hydrogen and carbon. Furthermore, the light hydrocarbon stream is comprised largely of C3 to C30 hydrocarbon molecules.
Preferably, the stream consists largely of Cs to C20 hydrocarbon molecules. Due to its higher vapor density, greater weights per period of lS time of light hydrocarbon can be passed through the drum than steam, further facilitating VCM removal. The light hydrocarbon stream should be introduced at a temperature lower than the coke temperature in the drum.
Furthermore, the light hydrocarbon stream should be introduced at a temperature below its boiling range, i.e., substantially as a liquid at 20 coke drum inlet pressure. Any hydrocarbon stream with a boiling range below the coke temperature can be used. Preferably, the light hydrocarbon has a final boiling point less than about 900F. More preferably, the final boilin~ point is less than about 600F. Blends of light hydrocarbons and/or steam are also envisioned. Preferably, the light 25 hydrocarbon stream has a limited coking potential. The preferred light hydrocarbons are naphtha, kerosene, or light gas oil. More preferably, the light hydrocarbon is naptha or kerosene.
With regard to Figure 1, kerosene is introduced through line 13.
Valves lOA and lOB direct flow into the filled "off-line" drum. The 30 kerosene is introduced at a temperature below its boiling point.
Preferably the kerosene is below about 450F. Therefore, the kerosene serves to extract heat from the coke as did steam in the prior art process. Accordingly, cycle time is not increased. In fact, better heat removal within the coke drum is achieved with light hydrocarbons rather 35 than steam due to the energy necessary for the vaporization of the light hydrocarbon stream. Accordingly, the kerosene transfers more heat from the lower portion of the coke drum to the upper portion of the coke drum, 2~ 339 thereby increasing the coking activity of the top portion which has been subjected to coking reaction temperatures for the shortest period of time.
In addition, the kerosene has a higher affinity for the tar-like VCM than steam and will effectively strip this material from the product 5 coke by extracting the VCM into the gas phase. Without being bound by theory, it is also believed that the light hydrocarbons, because they are very soluble in the VCM, cause swelling of the VCM resulting in VCM being pushed out of micro-pores and into the macro-pores and ~ channels increasing the accessibility of the solvent flow. Furthermore, the light 10 hydrocarbon reduces the viscosity of the VCM, making it more mobile.
The hot light hydrocarbon routed back to the bubble tower through line 11, carrying the VCM will function to stabilize the thermal requirements of the colunln during the "on-line" swing from drum 9A to 9B.
As stated above, when a illed drum is taken "off-line", the next "on-15 line" drum initially produces less overhead heat and vapor. In addition,the light hydrocarbon is fully miscible with the bubble tower contents, in contrast to steam, therefore it does not negatively effect the bubble tower operation.
The VCM solubilized by the kerosene can be collected from the 20 bubble tower as usable hydrocarbons which is a significant economical advantage. The kerosene can be recovered in the bubble tower and recycled through line 13 to maintain the process.
Although stripping of the coke bed with a light hydrocarbon can eliminate the need for steam stripping, it is possible to accompany the 25 light hydrocarbon stripping ~ith steam stripping or to subsequently steam strip.
Lines 15, 17, 19 and 21 are the recovery lines for various product fractions from the bubble tower. The bubble tower aids recovery of products SUC}I as heavy coker gas oil (line 21), a light coker gas oil 30 (line 19), kerosene (line 13), naphtha (line 17) and gas (line 15).
The following example is illustrative of a specific comparison of stripping with a light hydrocarbon as opposed to inert solvents.
Example 1. Coke which had previously been steam stripped, resulting in a 13.1 weight percent VCM content, was treated in a 150 cc.
35 microreactor at 850F and a pressure of 25 p.s.i.g. with solvents consisting of nitrogen, coker naphtha, and coker kerosene. The light hydrocarbon solvents resulted in much greater reduction of coke VCM.
.
3 ~ ~
SOLVENT STRIPPING OF COKE
Experimental Results:
Feed = Coke (13.1 wt% VCM) Temp = 850F
Pressure = 25 psig Solvent Product VCM
Nitrogen 13.0 wt%
Coker Naphtha 7.3 Coker Kerosene 7.6 Thus it is apparent that there has been provided, in accordance with the invention, a process that fully satisfies ehe objects, aims and 15 advantages set forth above. While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications, and 20 variations as fall within the spirit and broad scope within the appended claims.
SOLVENT STRIPPING OF COKE
Experimental Results:
Feed = Coke (13.1 wt% VCM) Temp = 850F
Pressure = 25 psig Solvent Product VCM
Nitrogen 13.0 wt%
Coker Naphtha 7.3 Coker Kerosene 7.6 Thus it is apparent that there has been provided, in accordance with the invention, a process that fully satisfies ehe objects, aims and 15 advantages set forth above. While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications, and 20 variations as fall within the spirit and broad scope within the appended claims.
Claims (13)
- WHAT IS CLAIMED:
l. A process for preparing coke having a low volatile carbonaceous matter content from a petroleum feedstock comprising:
a) heating and introducing a petroleum feedstock to a coke drum to form coke and overhead vapors;
b) passing a light hydrocarbon stream through said coke, wherein said light hydrocarbon stream enters said coke drum in a substantially liquid phase; and c) removing said light hydrocarbon containing at least a portion of the volatile carbonaceous matter from said coke drum. - 2. The process of claim 1, wherein said overhead vapors of step a and said light hydrocarbon stream of step c are passed to a bubble tower.
- 3. The process of claim 1, wherein said petroleum feedstock is introduced at 850°F or above.
- 4. The process of claim 1, wherein said light hydrocarbon stream has a boiling range below the temperature of said coke.
- 5. The process of claim 4, wherein said light hydrocarbon stream has a final boiling point less than about 900°F.
- 6. The process of claim 5, wherein said light hydrocarbon stream has a final boiling point less than about 600°F.
- 7. The process of claim 4, wherein said light hydrocarbon stream has a limited coking potential.
- 8. The process of claim 4, wherein said light hydrocarbon stream is selected from the group consisting of naphtha, kerosene, light gas oil, and blends thereof.
- 9. The process of claim 8, wherein said light hydrocarbon stream is selected from the group consisting of naptha and kerosene.
- 10. The process of claim 1, wherein said passing of said light hydrocarbon stream of step b is followed by steam stripping.
- 11. The process of claim 1, wherein said light hydrocarbon stream of step b is a blend of light hydrocarbon and steam.
- 12. The process or claim 2, wherein said light hydrocarbon is recycled through said bubble tower back to said coke drum.
- 13. The process of claim 1, wherein said light hydrocarbon stream of step b is a blend of light hydrocarbon, steam and any inert additive.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US51537790A | 1990-04-27 | 1990-04-27 | |
| US515,377 | 1990-04-27 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2041339A1 true CA2041339A1 (en) | 1991-10-28 |
Family
ID=24051097
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002041339A Abandoned CA2041339A1 (en) | 1990-04-27 | 1991-04-26 | Technique for reducing vcm coking |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0454425B1 (en) |
| AT (1) | ATE100486T1 (en) |
| CA (1) | CA2041339A1 (en) |
| DE (1) | DE69101023T2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| MX351574B (en) * | 2011-05-13 | 2017-10-18 | Catalytic Distillation Tech | Method for producing high vcm coke. |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4547284A (en) * | 1982-02-16 | 1985-10-15 | Lummus Crest, Inc. | Coke production |
-
1991
- 1991-04-23 EP EP91303657A patent/EP0454425B1/en not_active Expired - Lifetime
- 1991-04-23 AT AT91303657T patent/ATE100486T1/en active
- 1991-04-23 DE DE91303657T patent/DE69101023T2/en not_active Expired - Lifetime
- 1991-04-26 CA CA002041339A patent/CA2041339A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| DE69101023D1 (en) | 1994-03-03 |
| EP0454425B1 (en) | 1994-01-19 |
| EP0454425A1 (en) | 1991-10-30 |
| DE69101023T2 (en) | 1994-05-05 |
| ATE100486T1 (en) | 1994-02-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4331533A (en) | Method and apparatus for cracking residual oils | |
| US2340974A (en) | Refining process | |
| US4446009A (en) | Selective vaporization process and apparatus | |
| US4874505A (en) | Recycle of oily refinery wastes | |
| US4336160A (en) | Method and apparatus for cracking residual oils | |
| US3116231A (en) | Manufacture of petroleum coke | |
| US4394250A (en) | Delayed coking process | |
| US4216074A (en) | Dual delayed coking of coal liquefaction product | |
| US2296722A (en) | Cracking of hydrocarbon oils | |
| US5350503A (en) | Method of producing consistent high quality coke | |
| US4311579A (en) | Preparation of FCC charge by selective vaporization | |
| JPH09504823A (en) | Catalytic decomposition method | |
| US3591485A (en) | Combination catalytic cracking process | |
| CA1243979A (en) | Process for increasing deasphalted oil production from upgraded oil residua | |
| CA1202589A (en) | Process of thermally cracking heavy hydrocarbon oils | |
| US3997428A (en) | Vaporization of oil feed by addition of regenerated catalyst | |
| US4551232A (en) | Process and facility for making coke suitable for metallurgical purposes | |
| US2899380A (en) | Charge oil | |
| CA2888003C (en) | Method of processing low-grade heavy oil | |
| EP0454425B1 (en) | Process for producing coke with a low volatile carbonaceous matter content | |
| US4455221A (en) | Process for upgrading heavy hydrocarbons employing a diluent | |
| US2366218A (en) | Catalytic combination process | |
| US2723943A (en) | Hydrodesulfurizing hydrocarbons | |
| CA1246481A (en) | Coking residuum in the presence of hydrogen donor | |
| US2913395A (en) | Coking process |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |