Rapid thermal processing of heavy hydrocarbon feedstocks
09719021 · 2017-08-01
Assignee
Inventors
Cpc classification
International classification
Abstract
The present invention is directed to the upgrading of heavy hydrocarbon feedstock that utilizes a short residence pyrolytic reactor operating under conditions that cracks and chemically upgrades the feedstock. The method for upgrading a heavy hydrocarbon feedstock comprises introducing a particulate heat carrier into an upflow reactor, introducing the heavy hydrocarbon feedstock into the upflow reactor at a location above that of the particulate heat carrier so that a loading ratio of the particulate heat carrier to feedstock is from about 15:1 to about 200:1, allowing the heavy hydrocarbon feedstock to interact with the heat carrier with a residence time of less than about 1 second, to produce a product stream, separating the product stream from the particulate heat carrier, regenerating the particulate heat carrier, and collecting a gaseous and liquid product from the product stream.
Claims
1. A fast pyrolysis apparatus comprising: i) a feed system comprising a feed tank and a preheater for heating a feedstock; ii) a primary condenser downstream and in direct fluid communication with the feed tank through a feedstock line and further comprising a product collecting system; iii) an upflow pyrolysis reactor downstream and in fluid communication with the primary condenser through a primary product recycle line; iv) a particulate heat carrier separation system downstream and in fluid communication with the pyrolysis reactor; and v) a particulate heat carrier reheating/regenerating system.
2. The apparatus of claim 1, wherein the feed system is capable of introducing the heavy hydrocarbon feedstock into an upflow pyrolysis reactor.
3. The apparatus of claim 1, wherein the feed system is capable of regulating the flow of the preheated heavy hydrocarbon feedstock into the primary condenser.
4. The apparatus of claim 1, wherein the primary product recycle line further comprises a pre-heater unit.
5. The apparatus of claim 1, wherein the particulate heat carrier separation system is capable of separating a particulate heat carrier from a product stream and recycling the particulate heat carrier to the reheating/regenerating system.
6. The apparatus of claim 1, wherein the primary condenser and product collecting system is capable of cooling and collecting the feedstock product.
7. The apparatus of claim 1, wherein the product collecting system further comprises a secondary condenser.
8. The apparatus of claim 1, wherein the primary condenser and product collection system is configured to recover a lighter product fraction and a heavier product fraction and direct the heavier product fraction to the pyrolysis reactor.
9. The apparatus of claim 8, wherein the pyrolysis reactor is configured to accept the heavier product fraction just below a feedstock/heat carrier mixing zone in said upflow reactor.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings wherein:
(2)
(3)
(4)
(5)
(6)
DESCRIPTION OF THE PREFERRED EMBODIMENTS
(7) The present invention relates to the rapid thermal processing of viscous crude oil feedstocks. More specifically, this invention relates to the use of pyrolysis in order to upgrade and reduce the viscosity of these oils.
(8) The following description is of a preferred embodiment by way of example only and without limitation to the combination of features necessary for carrying the invention into effect.
(9) By “feedstock” it is generally meant a heavy hydrocarbon feedstock comprising, but not limited to, heavy oil or bitumens. However, the term “feedstock” may also include other hydrocarbon compounds such as petroleum crude oil, atmospheric tar bottom products, vacuum tar bottoms, coal oils, residual oils, tar sands, shale oil and asphaltic fractions. Furthermore, the feedstock may comprise significant amounts of BS&W (Bottom Sediment and Water), for example, but not limited to, a BS&W content of greater than 0.5% (wt %). Feedstock may also include pre-treated (pre-processed) feedstocks as defined below, however, heavy oil and bitumen are the preferred feedstock. These heavy oil and bitumen feedstocks are typically viscous and difficult to transport. Bitumens typically comprise a large proportion of complex polynuclear hydrocarbons (asphaltenes) that add to the viscosity of this feedstock and some form of pretreatment of this feedstock is required for transport. Such pretreatment typically includes dilution in solvents prior to transport.
(10) Typically tar-sand derived feedstocks (see Example 1 for an analysis of examples, which are not to be considered limiting, of such feedstocks) are pre-processed prior to upgrading, as described herein, in order to concentrate bitumen. However, pre-processing may also involve methods known within the art, including hot or cold water treatments, or solvent extraction that produces a bitumen-gas oil solution. These pre-processing treatments typically reduce the sand content of bitumen.
(11) For example one such water pre-processing treatment involves the formation of a tar-sand containing bitumen-hot water/NaOH slurry, from which the sand is permitted to settle, and more hot water is added to the floating bitumen to dilute out the base and ensure the removal of sand. Cold water processing involves crushing tar-sand in water and floating the bitumen containing tar-sands in fuel oil, then diluting the bitumen with solvent and separating the bitumen from the sand-water residue. A more complete description of the cold water process is disclosed in U.S. Pat. No. 4,818,373 (which is incorporated by reference). Such pre-processed or pre-treated feedstocks may also be used for further processing as described herein.
(12) Bitumens may be upgraded using the process of this invention, or other processes such as FCC, visbraking, hydrocracking etc. Pre-treatment of tar sand feedstocks may also include hot or cold water treatments, for example, to partially remove the sand component prior to upgrading the feedstock using the process as described herein, or other upgrading processes including FCC, hydrocracking, coking, visbreaking etc. Therefore, it is to be understood that the term “feedstock” also includes pre-treated feedstocks, including, but not limited to those prepared as described above.
(13) It is to be understood that lighter feedstocks may also be processed following the method of the invention as described herein. For example, and as described in more detail below, liquid products obtained from a first pyrolytic treatment as described herein, may be further processed by the method of this invention (for example composite recycle and multi stage processing; see
(14) The liquid product arising from the process as described herein may be suitable for transport within a pipeline to permit further processing of the feedstock elsewhere. Typically, further processing occurs at a site distant from where the feedstock is obtained. However, it is considered within the scope of the present invention that the liquid product produced using the present method may also be directly input into a unit capable of further upgrading the feedstock, such as, but not limited to, FCC, coking, visbreaking, hydrocraking, or pyrolysis etc. In this capacity, the pyrolytic reactor of the present invention partially upgrades the feedstock while at the same time acts as a pre-treater of the feedstock for further processing, as disclosed in, for example, but not limited to U.S. Pat. Nos. 5,662,868; 4,980,045; 4,818,373; 4,569,753; 4,435,272; 4,427,538; 4,427,539; 4,328,091; 4,311,580; 4,243,514; 4,294,686 (all of which are incorporated by reference herein).
(15) The feedstocks of the present invention are processed using a fast pyrolysis reactor, such as that disclosed in U.S. Pat. No. 5,792,340 (WO 91/11499; EP 513,051) involving contact times between the heat carrier and feedstock from about 0.01 to about 2 sec. Other known riser reactors with short residence times may also be employed, for example, but not limited to U.S. Pat. Nos. 4,427,539, 4,569,753, 4,818,373, 4,243,514 (which are incorporated by reference).
(16) It is preferred that the heat carrier used within the pyrolysis reactor exhibits low catalytic activity. Such a heat carrier may be an inert particulate solid, preferably sand, for example silica sand. By silica sand it is meant a sand comprising greater than about 80% silica, preferably greater than about 95% silica, and more preferably greater than about 99% silica. Other components of the silica sand may include, but are not limited to, from about 0.01% (about 100 ppm) to about 0.04% (400 ppm) iron oxide, preferably about 0.035% (358 ppm); about 0.00037% (3.78 ppm) potassium oxide; about 0.00688% (68.88 ppm) aluminum oxide; about 0.0027 (27.25) magnesium oxide; and about 0.0051% (51.14 ppm) calcium oxide. It is to be understood that the above composition is an example of a silica sand that can be used as a heat carrier as described herein, however, variations within the proportions of these ingredients within other silica sands may exist and still be suitable for use as a heat carrier. Other known inert particulate heat carriers or contact materials, for example kaolin clays, rutile, low surface area alumina, oxides of magnesium aluminum and calcium as described in U.S. Pat. No. 4,818,373 or U.S. Pat. No. 4,243,514, may also be used.
(17) Processing of feedstocks using fast pyrolysis results in the production of product vapours and solid byproducts associated with the heat carrier. After removal of the heat carrier from the product stream, the product vapours are condensed to obtain a liquid product and gaseous by-products. For example, which is not to be considered limiting, the liquid product produced from the processing of heavy oil, as described herein, is characterized in having the following properties: a boiling point of less than about 600° C., preferably less than about 525° C., and more preferably less than about 500° C.; an API gravity of at least about 12°, and preferably greater than about 17° (where API gravity=[141.5/specific gravity]−131.5; the higher the API gravity, the lighter the compound); greatly reduced metals content, including V and Ni. greatly reduced viscosity levels (more than 25 fold lower than that of the feedstock, for example, as determined @40° C.), and yields of liquid product of at least 60 vol %, preferably the yields are greater than about 70 vol %, and more preferably they are greater than about 80%.
(18) Following the methods as described herein, a liquid product obtained from processing bitumen feedstock, which is not to be considered limiting, is characterized as having: an API gravity from about 10 to about 21; a density @15° C. from about 0.93 to about 1.0; greatly reduced metals content, including V and Ni. a greatly reduced viscosity of more than 20 fold lower than the feedstock (for example as determined at 40° C.), and yields of liquid product of at least 60 vol %, preferably the yields are greater than about 75 vol %.
(19) The high yields and reduced viscosity of the liquid product produced according to this invention may permit the liquid product to be transported by pipeline to refineries for further processing with the addition of little or no diluents. Furthermore, the liquid products exhibit reduced levels of contaminants (e.g. metals and water), with the content of sulphur and nitrogen slightly reduced. Therefore, the liquid product may also be used as a feedstock, either directly, or following transport, for further processing using, for example, FCC, hydrocracking etc.
(20) Furthermore, the liquid products of the present invention may be characterised using Simulated Distillation (SimDist) analysis, as is commonly known in the art, for example but not limited to ASTM D 5307-97 or HT 750 (NCUT). SimDist analaysis, indicates that liquid products obtained following processing of heavy oil or bitumen can be characterized by any one of, or a combination of, the following properties (see Examples 1, 2 and 5): having less than 50% of their components evolving at temperatures above 538° C. (vacuum resid fraction); comprising from about 60% to about 95% of the product evolving below 538°. Preferably, from about 62% to about 85% of the product evolves during SimDist below 538° C. (i.e. before the vacuum resid. fraction); having from about 1.0% to about 10% of the liquid product evolve below 193° C. Preferably from about 1.2% to about 6.5% evolves below 193° C. (i.e. before the naphtha/kerosene fraction); having from about 2% to about 6% of the liquid product evolve between 193-232° C. Preferably from about 2.5% to about 5% evolves between 193-232° C. (kerosene fraction); having from about 10% to about 25% of the liquid product evolve between 232-327° C. Preferably, from about 13 to about 24% evolves between 232-327° C. (diesel fraction); having from about 6% to about 15% of the liquid product evolve between 327-360° C. Preferably, from about 6.5 to about 11% evolves between 327-360° C. (light VGO fraction); having from about 34.5% to about 60% of the liquid product evolve between 360-538° C. Preferably, from about 35 to about 55% evolves between 360-538° C. (Heavy VGO fraction);
(21) A first method for upgrading a feedstock to obtain liquid products with desired properties involves a one stage process. With reference to
(22) It is to be understood that other fast pyrolysis systems, comprising differences in reactor design, that utilize alternative heat carriers, heat carrier separators, different numbers or size of condensers, or different condensing means, may be used for the preparation of the upgraded product of this invention. For example, which is not to be considered limiting, reactors disclosed in U.S. Pat. Nos. 4,427,539, 4,569,753, 4,818,373, 4,243,514 (all of which are incorporated by reference) may be modified to operate under the conditions as outlined herein for the production of a chemically upgraded product with an increased API and reduced viscosity.
(23) Following pyrolysis of the feedstock in the prese.nce of the inert heat carrier, some contaminants present within the feedstock are deposited onto the inert heat carrier. These contaminants include metals (especially nickel and vanadium), coke, and to some extent nitrogen and sulphur. The inert heat carrier therefore requires regeneration (30) before re-introduction into the reaction stream. The heat carrier may be regenerated via combustion within a fluidized bed at a temperature of about 600 to about 900° C. Furthermore, as required, deposits may also be removed from the heat carrier by an acid treatment, for example as disclosed in U.S. Pat. No. 4,818,373 (which is incorporated by reference). The heated, regenerated, heat-carrier is then re-introduced to the reactor (20) and acts as heat carrier for fast pyrolysis.
(24) The feed system (10) provides a preheated feedstock to the reactor (20). An example of a feed system which is not to be considered limiting in any manner, is shown in
(25) Conversion of the feedstock is initiated in the mixing zone (170; e.g.
(26) The primary separation unit may be any suitable solids separation device, for example but not limited to a cyclone separator, a U-Beam separator, or Rams Horn separator as are known within the art. A cyclone separator is shown diagrammatically in
(27) The solids that have been removed in the primary and secondary collection systems are transferred to a vessel for regeneration of the heat carrier, for example, but not limited to a direct contact reheater system (30). In a direct contact reheater system (30), the coke and by-product gasses are oxidized to provide processes thermal energy which is directly carried to the solid heat carrier, as well as regenerating the heat carrier. The temperature of the direct contact reheater is maintained independent of the feedstock conversion (reactor) system. However, as indicated above, other methods for the regeneration of the heat carrier may be employed, for example but not limited to, acid treatment.
(28) The hot product stream from the secondary separation unit is quenched in a primary collection column (or primary condenser, 40;
(29) It is preferred that the reactor used with the process of the present invention is capable of producing high yields of liquid product for example at least greater than 60 vol %, preferably the yield is greater than 70 vol %, and more preferably the yield is greater than 80%, with minimal byproduct production such as coke and gas. Without wishing to limit the scope of the invention in any manner, an example for the suitable conditions for a the pyrolytic treatment of feedstock, and the production of a liquid product is described in U.S. Pat. No. 5,792,340, which is incorporated herein by reference. This process utilizes sand (silica sand) as the heat carrier, and a reactor temperature ranging from about 480° to about 620° C., loading ratios of heat carrier to feedstock from about 10:1 to about 200:1, and residence times from about 0.35 to about 0.7 sec. Preferably the reactor temperature ranges from about 500° to about 550° C. The preferred loading ratio is from about 15:1 to about 50:1, with a more preferred ratio from about 20:1 to about 30:1. Furthermore, it is to be understood that longer residence times within the reactor, for example up to about 5 sec, may be obtained if desired by introducing the feedstock within the reactor at a position towards the base of the reactor, by increasing the length of the reactor itself, by reducing the velocity of the heat carrier through the reactor (provided that there is sufficient velocity for the product vapour and heat carrier to exit the reactor), or a combination thereof. The preferred residence time is from about 0.5 to about 2 sec.
(30) Without wishing to be bound by theory, it is thought that the chemical upgrading of the feedstock that takes place within the reactor system as described above is in part due to the high loading ratios of feedstock to heat carrier that are used within the method of the present invention. Prior art loading ratios typically ranged from 5:1 to about 12.5:1. However, the loading ratios as described herein, of from about 15:1 to about 200:1, result in a very rapid, ablative and consistent transfer of heat from the heat carrier to the feedstock. The high volume and density of heat carrier within the mixing and conversion zones, ensures that a rapid and even processing temperature is achieved and maintained. In this way the temperatures required for cracking process described herein are easily controlled. This also allows for the use of relatively low temperatures to minimize over cracking, while ensuring that mild cracking of the feedstock is still achieved. Furthermore, with an increased density of heat carrier within the reactor, contaminants and undesired components present in the feedstock and reaction by-products, including metals (e.g. nickel and vanadium), coke, and to some extent nitrogen and sulphur, are readily adsorbed due to the large surface area of heat carrier present. This ensures efficient and optimal removal of contaminants from the feedstock, during the pyrolytic processing of the feedstock. As a larger surface area of heat carrier is employed, the heat carrier itself is not unduly contaminated, and any adsorbed metal or coke and the like is readily stripped during regeneration of the heat carrier. With this system the residence times can be carefully regulated in order to optimize the processing of the feedstock and liquid product yields.
(31) The liquid product arising from the processing of heavy oil as described herein has significant conversion of the resid fraction when compared to heavy oil or bitumen feedstock. As a result the liquid product of the present invention, produced from the processing of heavy oil is characterized, for example, but which is not to be considered limiting, as having an API gravity of at least about 13°, and more preferably of at least about 17°. However, as indicated above, higher API gravities may be achieved with a reduction in volume. For example, one liquid product obtained from the processing of heavy oil using the method of the present invention is characterized as having from about 10 to about 15% by volume bottoms, from about 10 to about 15% by volume light ends, with the remainder as middle distillates.
(32) The viscosity of the liquid product produced from heavy oil is substantially reduced from initial feedstock levels, of from 250 cSt 80° C., to product levels of 4.5 to about 10 cSt 80° C., or from about 6343 cSt @40° C., in the feedstock, to about 15 to about 35 cSt @40° C. in the liquid product. Following a single stage process, liquid yields of greater than 80 vol % and API gravities of about 17, with viscosity reductions of at least about 25 times that of the feedstock are obtained (@40° C.). These viscosity levels are suitable for pipeline transport of the liquid product. Results from Simulated Distillation (SimDist; e.g. ASTM D 5307-97, HT 750, (NCUT)) analysis further reveals substantially different properties between the feedstock and liquid product as produced herein. For heavy oil feedstock, approx. 1% (wt %) of the feedstock is distilled off below about 232° C. (Kerosene fraction), approx. 8.7% from about 232° to about 327° C. (Diesel fraction), and 51.5% evolved above 538° C. (Vacuum resid fraction; see Example 1 for complete analysis) SimDist analysis of the liquid product produced as described above may be characterized as having, but is not limited to having, the following properties: approx. 4% (wt %) evolving below about 232° C. (Kerosene fraction), approx. 14.2% from about 232° to about 327° C. (Diesel fraction), and 37.9% within the vacuum resid fraction (above 538° C.). It is to be understood that modifications to these values may arise depending upon the composition of the feedstock used. These results demonstrate that there is a significant alteration in many of the components within the liquid product when compared with the heavy oil feedstock, with a general trend to lower molecular weight components that evolve earlier during SimDist analysis following rapid thermal processing.
(33) Therefore, the present invention is directed to a liquid product obtained from single stage processing of heavy oil may that may be characterised by at least one of the following properties: having less than 50% of their components evolving at temperatures above 538° C. (vacuum resid fraction); comprising from about 60% to about 95% of the product evolving below 538°. Preferably, from about 60% to about 80% evolves during Simulated Distillation below 538° C. (i.e. before the vacuum resid. fraction); having from about 1.0% to about 6% of the liquid product evolve below 193° C. Preferably from about 1.2% to about 5% evolves below 193° C. (i.e. before the naphtha/kerosene fraction); having from about 2% to about 6% of the liquid product evolve between 193-232° C. Preferably from about 2.8% to about 5% evolves between 193-232° C. (diesel fraction); having from about 12% to about 25% of the liquid product evolve between 232-327° C. Preferably, from about 13 to about 18% evolves between 232-327° C. (diesel fraction); having from about 5% to about 10% of the liquid product evolve between 327-360° C. Preferably, from about 6.0 to about 8.0% evolves between 327-360° C. (light VGO fraction); having from about 40% to about 60% of the liquid product evolve between 360-538° C. Preferably, from about 30 to about 45% evolves between 360-538° C. (Heavy VGO fraction);
(34) Similarly following the methods as described herein, a liquid product obtained from processing bitumen feedstock following a single stage process, is characterized as having, and which is not to be considered as limiting, an increase in API gravity of at least about 10 (feedstock API is typically about 8.6). Again, higher API gravities may be achieved with a reduction in volume. The product obtained from bitumen is also characterised as having a density from about 0.93 to about 1.0 and a greatly reduced viscosity of at least about 20 fold lower than the feedstock (i.e. from about 15 g/ml to about 60 g/ml at 40° C. in the product, v. the feedstock comprising about 1500 g/ml). Yields of liquid product obtained from bitumen are at least 60% by vol, and preferably greater than about 75% by vol. SimDist analysis also demonstrates significantly different properties between the bitumen feedstock and liquid product as produced herein. Highlights from SimDist analysis indicates that for a bitumen feedstock, approx. 1% (wt %) of the feedstock was distilled off below about 232° C. (Kerosene fraction), approx. 8.6% from about 232° to about 327° C. (Diesel fraction), and 51.2% evolved above 538° C. (Vacuum resid fraction; see Example 2 for complete analysis). SimDist analysis of the liquid product produced from bitumen as described above may be characterized, but is not limited to the following properties: approx. 5.7% (wt %) is evolved below about 232° C. (Kerosene fraction), approx. 14.8% from about 232° to about 327° C. (Diesel fraction), and 29.9% within the vacuum resid fraction (above 538° C.). Again, these results may differ depending upon the feedstock used, however, they demonstrate the significant alteration in many of the components within the liquid product when compared with the bitumen feedstock, and the general trend to lower molecular weight components that evolve earlier during SimDist analysis in the liquid product produced from rapid thermal processing.
(35) Therefore, the present invention is also directed to a liquid product obtained from single stage processing of bitumen which is characterised by having at least one of the following properties: having less than 50% of their components evolving at temperatures above 538° C. (vacuum resid fraction); comprising from about 60% to about 95% of the product evolving below 538°. Preferably, from about 60% to about 80% evolves during Simulated Distillation below 538° C. (i.e. before the vacuum resid. fraction); having from about 1.0% to about 6% of the liquid product evolve below 193° C. Preferably from about 1.2% to about 5% evolves below 193° C. (i.e. before the naphtha/kerosene fraction); having from about 2% to about 6% of the liquid product evolve between 193-232° C. Preferably from about 2.0% to about 5% evolves between 193-232° C. (diesel fraction); having from about 12% to about 25% of the liquid product evolve between 232-327° C. Preferably, from about 13 to about 18% evolves between 232-327° C. (diesel fraction); having from about 5% to about 10% of the liquid product evolve between 327-360° C. Preferably, from about 6.0 to about 8.0% evolves between 327-360° C. (light VGO fraction); having from about 40% to about 60% of the liquid product evolve between 360-538° C. Preferably, from about 30 to about 50% evolves between 360-538° C. (Heavy VGO fraction);
(36) The liquid product produced as described herein also exhibits a high degree of stability. Analysis of the liquid product over a 30 day period indicates negligible change in SimDist profile, viscosity, API and density for liquid products produced from either heavy oil or bitumen feedstocks (see Example 1 and 2).
(37) Because the crack is not as severe, and the residence time short, unwanted reactions that can generate excessive amounts of undesirable aromatics and olefins. Furthermore, it has been found that contaminants such as metals and water are significantly reduced. There is no concentration of contaminants in the liquid product.
(38) Also as disclosed herein, further processing of the liquid product obtained from the process of heavy oil or bitumen feedstock may take place following the method of this invention. Such further processing may utilize conditions that are very similar to the initial fast pyrolysis treatment of the feedstock, or the conditions may be modified to enhance removal of lighter products (a single-stage process with a mild crack) followed by more severe cracking of the recycled fraction (i.e. a two stage process).
(39) In the first instance, that of further processing under similar conditions the liquid product from a first pyrolytic treatment is recycled back into the pyrolysis reactor in order to further upgrade the properties of the final product to produce a lighter product. In this arrangement the liquid product from the first round of pyrolysis is used as a feedstock for a second round of pyrolysis after the lighter fraction of the product has been removed from the product stream. Furthermore, a composite recycle may also be carried out where the heavy fraction of the product stream of the first process is fed back (recycled) into the reactor along with the addition of fresh feedstock (e.g.
(40) The second method for upgrading a feedstock to obtain liquid products with desired properties involves a two-stage pyrolytic process (see
(41) Following such a two stage process, an example of the product, which is not to be considered limiting, of the first stage (light boilers) is characterized with a yield of about 30 vol %, an API of about 19, and a several fold reduction in viscosity over the initial feedstock. The product of the high boiler fraction, produced following the processing of the recycle fraction in the second stage, is typically characterized with a yield greater than about 75 vol %, and an API gravity of about 12, and a reduced viscosity over the feedstock recycled fraction. SimDist analysis for liquid product produced from heavy oil feedstock is characterized with approx. 7.4% (wt %) of the feedstock was distilled off below about 232° C. (Kerosene fraction v. 1.1% for the feedstock), approx. 18.9% from about 232° to about 327° C. (Diesel fraction v. 8.7% for the feedstock), and 21.7% evolved above 538° C. (Vacuum resid fraction v. 51.5% for the feedstock; see Example 1 for complete analysis). SimDist analysis for liquid product produced from bitumen feedstock is characterized with approx. 10.6% (wt %) of the feedstock was distilled off below about 232° C. (Kerosene fraction v. 1.0% for the feedstock), approx. 19.7% from about 232° to about 327° C. (Diesel fraction v. 8.6% for the feedstock), and 19.5% evolved above 538° C. (Vacuum resid fraction v. 51.2% for the feedstock; see Example 2 for complete analysis).
(42) Alternate conditions of a two stage process may include a first stage run where the feedstock is preheated to 150° C. and injected into the reactor and processed at about 530° to about 620° C., and with a residence time less than one second within the reactor (see
(43) Yet another modification of the composite and two stage processing systems, termed “multi-stage” processing, comprises introducing the primary feedstock (raw feed) into the primary condenser (see
(44) Alternate feeds systems may also be used as required for one, two, composite or multi stage processing. For example, in the system outlined
(45) Following the recycle process as outlined above and graphically represented in
(46) From SimDist analaysis, liquid products obtained following multi-stage processing of heavy oil can be characterized by comprising at least one of the following properties: having less than 50% of their components evolving at temperatures above 538° C. (vacuum resid fraction); comprising from about 60% to about 95% of the product evolving below 538°. Preferably, from about 70% to about 90%, and more preferably from about 75 to about 87% of the product evolves during Simulated Distillation below 538° C. (i.e. before the vacuum resid. fraction); having from about 1.0% to about 6% of the liquid product evolve below 193° C. Preferably from about 1.2% to about 5%, and more preferably from about 1.3% to about 4.8% evolves below 193° C. (i.e. before the naphtha/kerosene fraction); having from about 2% to about 6% of the liquid product evolve between 193-232° C. Preferably from about 2.8% to about 5% evolves between 193-232° C. (diesel fraction); having from about 15% to about 25% of the liquid product evolve between 232-327° C. Preferably, from about 18.9 to about 23.1% evolves between 232-327° C. (diesel fraction); having from about 8% to about 15% of the liquid product evolve between 327-360° C. Preferably, from about 8.8 to about 10.8% evolves between 327-360° C. (light VGO fraction); having from about 40% to about 60% of the liquid product evolve between 360-538° C. Preferably, from about 42 to about 55% evolves between 360-538° C. (Heavy VGO fraction);
(47) The liquid product obtained from multi-stage processing of bitumen may be charachterized as having at least one of the following properties: having less than 50% of their components evolving at temperatures above 538° C. (vacuum resid fraction); comprising from about 60% to about 95% of the product evolving below 538°. Preferably, from about 60% to about 85% evolves during Simulated Distillation below 538° C. (i.e. before the vacuum resid. fraction); having from about 1.0% to about 8% of the liquid product evolve below 193° C. Preferably from about 1.5% to about 7% evolves below 193° C. (i.e. before the naphtha/kerosene fraction); having from about 2% to about 6% of the liquid product evolve between 193-232° C. Preferably from about 2.5% to about 5% evolves between 193-232° C. (diesel fraction); having from about 12% to about 25% of the liquid product evolve between 232-327° C. Preferably, from about 15 to about 20% evolves between 232-327° C. (diesel fraction); having from about 5% to about 12% of the liquid product evolve between 327-360° C. Preferably, from about 6.0 to about 10.0% evolves between 327-360° C. (light VGO fraction); having from about 40% to about 60% of the liquid product evolve between 360-538° C. Preferably, from about 35 to about 50% evolves between 360-538° C. (Heavy VGO fraction);
(48) Collectively these results show that a substantial proportion of the components with low volatility in either of the feedstocks have been converted to components of higher volatility (light naphtha, kerosene and diesel) in the liquid product. These results demonstrate that the liquid product are substantially upgraded, and exhibits properties suitable for transport.
(49) The above description is not intended to limit the claimed invention in any manner, furthermore, the discussed combination of features might not be absolutely necessary for the inventive solution.
(50) The present invention will be further illustrated in the following examples. However it is to be understood that these examples are for illustrative purposes only, and should not be used to limit the scope of the present invention in any manner.
Example 1
Heavy Oil (Single Stage)
(51) Pyrolytic processing of Saskatchewan Heavy Oil and Athabasca Bitumen (see Table 1) were carried out over a range of temperatures using a pyrolysis reactor as described in U.S. Pat. No. 5,792,340.
(52) TABLE-US-00001 TABLE 1 Characteristics of heavy oil and bitumen feedstocks Compound Heavy Oil.sup.1 Bitumen.sup.2 Carbon (wt %) 84.27 83.31 Hydrogen (wt %) 10.51 10.31 Nitrogen (wt %) <0.5 <0.5 Sulphur (st %) 3.6 4.8 Ash (wt %) 0.02 0.02 Vanadium (ppm) 127 204 Nickel (ppm) nd 82 Water content (wt %) 0.8 0.19 Gravity API° 11.0 8.6 Viscosity @ 40° C. (cSt) 6343 30380 Viscosity @ 60° C. (cSt) 892.8 1268.0 Viscosity @ 80° C. (cSt) 243.4 593.0 Aromaticity (C13 NMR) 0.31 0.35 .sup.1Saskatchewan Heavy Oil .sup.2Athabasca Bitumen (neat)
(53) Briefly the conditions of processing include a reactor temperature from about 500° to about 620° C. Loading ratios for particulate heat carrier (silica sand) to feedstock of from about 20:1 to about 30:1 and residence times from about 0.35 to about 0.7 sec. These conditions are outlined in more detail below (Table 2).
(54) TABLE-US-00002 TABLE 2 Single stage processing of Saskatchewan Heavy Oil Crack Temp Viscosity @ Yield Density @ ° C. 40° C. (cSt) wt % 15° g/ml API° Yield Vol % 620 4.6.sup.1 71.5 0.977 13.3 72.7 592 15.2.sup.1 74.5 0.970 14.4 76.2 590 20.2 70.8 0.975 13.6 72.1 590 31.6 75.8 0.977 13.3 77.1 560 10.01.sup.1 79.9.sup.2 0.963 15.4 82.3.sup.2 560 10.01.sup.1 83.0.sup.3 0.963 16.2.sup.3 86.3.sup.3 550 20.8 78.5 0.973 14.0 80.3 .sup. 550.sup.4 15.7 59.8.sup.2 0.956 16.5 61.5.sup.2 .sup. 550.sup.4 15.7 62.0.sup.3 0.956 18.3.sup.2,3 65.1.sup.3 530 32.2 80.9.sup.2 0.962 15.7 82.8.sup.2 530 32.2 83.8.sup.3 0.962 16.6.sup.3 87.1.sup.3 .sup.1Viscosity @ 80° C. .sup.2Yields do not include overhead condensing .sup.3Estimated yields and API with overhead condensing .sup.4Not all of the liquids were captured in this trial.
(55) The liquid products of the runs at 620° C., 592° C. and 560° C. were analysed for metals, water and sulphur content. These results are shown in Table 3. Nickel, Vanadium and water levels were reduced 72, 69 and 87%, respectively, while sulphur and nitrogen remained the same or were marginally reduced. No metals were concentrated in the liquid product.
(56) TABLE-US-00003 TABLE 3 Metal Analysis of Liquid Products (ppm).sup.1 Saskatchewan Run @ Run @ Component Heavy Oil 620° C. Run @ 592° C. 560° C. Aluminum <1 <1 11 <1 Iron <1 2 4 <1 Nickel 44 10 12 9 Zinc 2 <1 2 1 Calcium 4 2 3 1 Magnesium 3 1 2 <1 Boron 21 42 27 <1 Sodium 6 5 5 4 Silicon 1 10 140 4 Vanadium 127 39 43 39 Potassium 7 7 <1 4 Water (wt %) 0.78 0.19 0.06 .10 Sulphur (wt %) 3.6 3.5 3.9 3.5 .sup.1Copper, tin, chromium, lead, cadmium, titanium, molybdenum, barium and manganese all showed less than 1 ppm in feedstock and liquid products.
(57) The gas yields for two runs are presented in Table 4.
(58) TABLE-US-00004 TABLE 4 Gas analysis of Pyrolysis runs Gas (wt %) Run @620° C. Run @ 560° C. Total Gas Yield 11.8 7.2 Ethylene 27.0 16.6 Ethane 8.2 16.4 Propylene 30.0 15.4 Methane 24.0 21.0
(59) The pour point of the feedstock improved and was reduced from 32° F. to about −54° F. The Conradson carbon reduced from 12. wt % to about 6.6 wt %.
(60) Based on the analysis of these runs, higher API values and product yields were obtained for crack temperatures of about 530 to about 560° C. At these temperatures, API gravities of 14 to 18.3, product yields of from about 80 to about 87 vol %, and viscosities of from about 15 to about 35 cSt (@40° C.) or about 10 cST (@80° C.) were obtained (the yields from the 550° C. run are not included in this range as the liquid yield capture was not optimized during this run). These liquid products reflect a significant degree of upgrading, and exhibit qualities suitable for pipeline transport.
(61) Simulated distillation (SimDist) analysis of feedstock and liquid product obtained from several separate runs is present in Table 5. SimDist analysis followed the protocol outlined in ASTM D 5307-97, which reports the residue as anything with a boiling point higher than 538° C. Other methods for SimDist may also be used, for example HT 750 (NCUT; which includes boiling point distribution through to 750° C.). These results indicate that over 50% of the components within the feedstock evolve at temperatures above 538° C. These are high molecular weight components with low volatility. Conversely, in the liquid product, the majority of the components, approx 62.1% of the product are more volatile and evolve below 538° C.
(62) TABLE-US-00005 TABLE 5 SimDist anlaysis of feedstock and liquid product after single stage processing (Reactor temp 538° C.) Fraction Temp (° C.) Feedstock R245 Light Naphtha <71 0.0 0.5 Light/med Naphtha 71-100 0.0 0.3 Med Naphtha 100-166 0.0 1.4 Naphtha/Kerosene 166-193 0.1 1.0 Kerosene 193-232 1.0 2.8 Diesel 232-327 8.7 14.2 Light VGO 327-360 5.2 6.5 Heavy VGO 360-538 33.5 35.2 Vacuum Resid. >538 51.5 37.9
(63) The feedstock can be further characterized with approx. 0.1% of its components evolving below 193° C. (naphtha/kerosene fraction), v. approx. 6% for the liquid product. The diesel fraction also demonstrates significant differences between the feedstock and liquid product with 8.7% and 14.2% evolving at this temperature range (232-327° C.), respectively. Collectively these results show that a substantial proportion of the components with low volatility in the feedstock have been converted to components of higher volatitly (light naphtha, kerosene and diesel) in the liquid product.
(64) Stability of the liquid product was also determined over a 30 day period (Table 6). No significant change in the viscosity, API or density of the liquid product was observed of a 30 day period.
(65) TABLE-US-00006 TABLE 6 Stabilty of liquid products after single stage processing Fraction Time = 0 7 days 14 days 30 days Density @ 15.6° C. (g/cm3) 0.9592 0.9590 0.9597 0.9597 API (deg. API) 15.9 15.9 15.8 15.8 Viscosity @40° C. (cSt) 79.7 81.2 81.2 83.2
Example 2
Bitumen (Single Stage)
(66) Several runs using Athabaska Bitumen were conducted using the pyrolysis reactor described in U.S. Pat. No. 5,792,340. The conditions of processing included a reactor temperature from 520° to about 590° C. Loading ratios for particulate heat carrier to feedstock of from about 20:1 to about 30:1, and residence times from about 0.35 to about 1.2 sec. These conditions, and the resulting liquid products are outlined in more detail below (Table 7).
(67) TABLE-US-00007 TABLE 7 Single Stage Processing with Undiluted Athabasca Bitumen Viscosity Crack @ 40° C. Yield Density @ Metals V Metals Ni Temp (cSt) wt % 15° C. (ppm)* (ppm)** API 519° C. 205 81.0 nd nd nd 13.0 525° C. 201 74.4 0.979 88 24 12.9 528° C. 278 82.7 nd nd nd 12.6 545° C. 151 77.4 0.987 74 27 11.8 590° C. 25.6 74.6 0.983 rid nd 12.4 *feedstock V 209 ppm **feedstock Ni 86 ppm
(68) These results indicates that undiluted bitumen may be processed according to the method of this invention to produce a liquid product with reduced viscosity from greater than 1300 cSt (@40° C.) to about 25.6-200 cSt (@40° C. (depending on the run conditions; see also Tables 8 and 9), with yields of over 75% to about 85%, and an improvement in the product API from 8.6 to about 12-13. Again, as per Example 1, the liquid product exhibits substantial upgrading of the feedstock. SinaDist analysis, and other properties of the liquid product are presented in Table 8, and stability studies in Table 9.
(69) TABLE-US-00008 TABLE 8 Properties and SimDist analysis of feedstock and liquid product after single stage processing (Reactor temp. 545° C.). R239 Fraction Temp (° C.) Feedstock 14 days 30 days Density @15.5° C. — 0.9871 0.9876 API — 11.7 11.6 Viscosity @ 40° C. 162.3 169.4 Light Naphtha <71 0.0 0.2 0.1 Light-med Naphtha 71-100 0.0 0.2 0.2 Med Naphtha 100-166 0.0 1.5 1.4 Naphtha/Kerosne 166-193 0.1 1.0 1.0 Kerosene 193-232 0.9 3.1 3.0 Diesel 232-327 8.6 15.8 14.8 Light VGO 327-360 5.2 7.9 7.6 Heavy VGO 360-538 34.0 43.9 42.0 Vacuum Resid. >538 51.2 26.4 29.9
(70) TABLE-US-00009 TABLE 9 Stabilty of liquid products after single stage processing (reactor temperature 525° C.) Temp R232 Fraction (° C.) Feedstock day 0 7 days 14 days 30 days Density @ — 1.0095 0.979 0.980 0.981 0.981 15.6@ C* API — 8.5 12.9 12.7 12.6 12.6 Vis- — 30380 201.1 213.9 214.0 218.5 cosity @ 40° C.** Light <71 0.0 0.1 0.1 0.1 0.1 Naphtha Light/med 71-100 0.0 0.1 0.1 0.1 0.1 Naphtha Med 100-166 0.0 1.5 1.5 1.5 1.4 Naphtha Naphtha/ 166-193 0.1 1.0 1.0 1.0 1.1 Kerosne Kerosene 193-232 1.0 2.6 2.6 2.6 2.7 Diesel 232-327 8.7 14.1 14.1 14.3 14.3 Light 327-360 5.2 7.3 7.3 7.4 7.4 VGO Heavy 360-538 33.5 41.3 41.3 41.7 42.1 VGO Vacuum >538 51.5 32.0 32.0 31.2 30.8 Resid. *g./cm3 **cSt
(71) The slight variations in the values presented in the stability studies (Table 9 and other stability studies disclosed herein) are within the error of the test methods employed, and are acceptable within the art. These results demonstrate that the liquid products are stable.
(72) These results indicate that over 50% of the components within the feedstock evolve at temperatures above 538° C. (vacuum resid fraction). This fraction is characterized by high molecular weight components with low volatility. Conversely, over several runs, the liquid product is characterized as comprising approx 68 to 74% of the product that are more volatile and evolve below 538° C. The feedstock can be further characterized with approx. 0.1% of its components evolving below 193° C. (naphtha/kerosene fraction), v. approx. 2.7 to 2.9% for the liquid product. The diesel fraction also demonstrates significant differences between the feedstock and liquid product with 8.7% (feedstock) and 14.1 to 15.8% (liquid product) evolving at this temperature range (232-327° C.). Collectively these results show that a substantial proportion of the components with low volatility in the feedstock have been converted to components of higher volatitly (light naphtha, kerosene and diesel) in the liquid product. These results demonstrate that the liquid product is substantially upgraded, and exhibits properties suitable for transport.
Example 3
Composite/Recycle of Feedstock
(73) The pyrolysis reactor as described in U.S. Pat. No. 5,792,340 may be configured so that the recovery condensers direct the liquid products into the feed line to the reactor (see
(74) The conditions of processing included a reactor temperature ranging from about 530° to about 590° C. Loading ratios for particulate heat carrier to feedstock for the initial and recycle run of about 30:1, and residence times from about 0.35 to about 0.7 sec were used. These conditions are outlined in more detail below (Table 10). Following pyrolysis of the feedstock, the lighter fraction was removed and collected using a hot condenser placed before the primary condenser (see
(75) TABLE-US-00010 TABLE 10 Composite/Recycle operation using Saskatchewan Heavy Crude Oil and Undiluted Athabasca Bitumen Crack Recycle.sup.4 Recycle.sup.4 Feedstock Temp ° C. Yield Vol % API° Yield Vol % API° Heavy Oil 590 77.1.sup.1 13.3 68.6 17.1 560 86.3.sup.2 16.2 78.1 21.1 550 50.1.sup.1 14.0 71.6 17.8 550 65.1.sup.2,3 18.3 56.4 22.9 530 87.1.sup.2 16.6 78.9 21.0 Bitumen 590 75.2.sup.2 12.4 67.0 16.0 .sup.1Yield and API gravity include overhead condensing (actual) .sup.2Yield and API gravity include overhead condensing (estimated) .sup.3Not all of the liquid was recovered in this .sup.4These values represent the total recovery of product following the recycle run, and presume the removal of approximately 10% heavy fraction which is recycled to extinction. This is therefore a conservative estimate of yield as some of the heavy fraction will produce lighter components that enter the product stream, since not all of the heavy fraction will end up as coke.
(76) The API gravity increased from 11.0 in the heavy oil feedstock to about 13 to about 18.5 after the first treatment cycle, and further increases to about 17 to about 23 after a second recycle treatment. A similar increase in API is observed for bitumen having a API of about 8.6 in the feedstock, which increase to about 12.4 after the first run and to 16 following the recycle run. With the increase in API, there is an associated increase in yield from about 77 to about 87% after the first run, to about 67 to about 79% following the recycle run. Therefore associated with the production of a lighter product, there is a decrease in liquid yield. However, an upgraded lighter product may be desired for transport, and recycling of liquid product achieves such a product.
Example 4
Two-Stage Treatment of Heavy Oil
(77) Heavy oil or bitumen feedstock may also be processed using a two-stage pyrolytic process which comprises a first stage where the feedstock is exposed to conditions that mildly crack the hydrocarbon components in order to avoid overcracking and excess gas and coke production. Lighter materials are removed following the processing in the first stage, and the remaining heavier materials are subjected to a more severe crack at a higher temperature. The conditions of processing within the first stage include a reactor temperature ranging from about 510 to about 530° C. (data for 515° C. given below), while in the second stage, a temperature from about 590° to about 800° C. (data for 590° C. presented in table 11) was employed. The loading ratios for particulate heat carrier to feedstock range of about 30:1, and residence times from about 0.35 to about 0.7 sec for both stages. These conditions are outlined in more detail below (Table 11).
(78) TABLE-US-00011 TABLE 11 Two-Stage Runs of Saskatchewan Heavy Oil Crack Viscosity @ Yield Density @ Temp. ° C. 80° C. (cSt) wt % 15° C. g/ml API° Yield Vol %.sup.1) 515 5.3 29.8 0.943 18.6 31.4 590 52.6 78.9 0.990 11.4 78.1 515 &590 nd nd nd 13.9 86.6 “nd” means not determined .sup.1)Light condensible materials were not captured. Therefore these values are conservative estimates.
(79) These results indicate that a mild initial crack which avoids overcracking light materials to gas and coke, followed by a more severe crack of the heavier materials produces a liquid product characterized with an increased API, while still exhibiting good product yields.
(80) Other runs using a two stage processes, involved injecting the feedstock at about 150° C. into a hot gas stream maintained at about 515° C. and entering the reactor at about 300° C. (processing temperature). The product, comprising lighter materials (low boilers) was separated and removed following the first stage in the condensing system. The heavier materials, separated out at the bottom of the cyclone were collected subjected to a more severe crack within the reactor in order to render a liquid product of reduced viscosity and high yield. The conditions utilized in the second stage were a processing temperature of between about 530° to about 590° C. Product from the second stage was processed and collected.
(81) Following such a two stage process the product of the first stage (light boilers) is characterized with a yield of about 30 vol %, an API of about 19, and a several fold reduction in viscosity over the initial feedstock. The product of the high boiling point fraction, produced following the processing of the recycle fraction in the second stage, is typically characterized with a yield greater than about 75 vol %, and an API gravity of about 12, and a reduced viscosity over the feedstock recycled fraction.
Example 5
“Multi-Stage” Treatment of Heavy Oil and Bitumen, Using Feedstock for Quenching within Primary Condenser
(82) Heavy oil or bitumen feedstock may also be processed using a “Multi-stage” pyrolytic process as outlined in
(83) The conditions of processing included a reactor temperature ranging from about 530° to about 590° C. Loading ratios for particulate heat carrier to feedstock for the initial and recycle run of from about 20:1 to about 30:1, and residence times from about 0.35 to about 1.2 sec were used. These conditions are outlined in more detail below (Table 12). Following pyrolysis of the feedstock, the lighter fraction is forwarded to the secondary condenser while the heavier fraction of the liquid product obtained from the primary condenser is recycled back to the reactor for further processing (
(84) TABLE-US-00012 TABLE 12 Charaterization of the liquid product obtained following Multi-Stage processing of Saskatchewan Heavy Oil and Bitumen Crack Viscosity @ Yield Density @ Yield Temp. ° C. 40° C. (cSt) wt % 15.6° C. g/ml API° Vol %.sup.1) Heavy Oil 543 80 62.6 0.9592 15.9 64.9 557 24 58.9 0.9446 18.2 62.1 561 53 70.9 0.9568 16.8 74.0 Bitumen 538 40 61.4 0.9718 14.0 71.1
(85) The liquid products produced from multi-stage processing of feedstock exhibit properties suitable for transport with greatly reduced viscosity down from 6343 cSt (@40° C.) for heavy oil and 30380 cSt (@40° C.) for bitumen. Similarly, the API increased from 11 (heavy oil) to from 15.9 to 18.2, and from 8.6 (bitumen) to 14.7. Furthermore, yeilds for heavy oil under these reaction conditions are from 59 to 68% for heavy oil, and 82% for bitumen.
(86) TABLE-US-00013 TABLE 13 Properties and SimDist of liquid products prepared from Heavy Oil using the multi-stage Process (for feedstock properties see Tables 1 and 5). Temp R241* R242** R244*** Fraction (° C.) Day 0 Day 30 Day 30 Density @ 15.6° C. — 0.9592 0.9597 0.9465 0.9591 API 15.9 15.8 17.8 15.9 Viscosity @40° C. 79.7 83.2 25.0 49.1 Light Naphtha <71 0.0 0.2 0.3 0.3 Light/med Naphtha 71-100 0.0 0.1 0.2 0.3 Med Naphtha 100-166 0.1 0.4 2.5 1.8 Naphtha/Kerosne 166-193 0.6 0.6 1.8 1.5 Kerosene 193-232 2.8 2.5 5.0 3.5 Diesel 232-327 21.8 21.0 23.1 18.9 Light VGO 327-360 10.8 10.2 9.9 8.8 Heavy VGO 360-538 51.1 45.0 44.9 43.2 Vacuum Resid. >538 12.7 20.0 12.3 21.7 *reactor temp. 543° C. **reactor temp. 557° C. ***reactor temp. 561° C.
(87) Under these run conditions the API increased from 11 to about 15.9 to 17.8. Product yields of 62.6 (wt %; R241), 58.9 (wt %; R242) and 70.9 (wt %; R244) were achieved along with greatly reduced viscosity levels. These liquid products have been substantially upgraded over the feedstock and exhibit properties suitable for pipeline transport.
(88) SimDist results indicate that over 50% of the components within the feedstock evolve at temperatures above 538° C. (vacuum resid fraction), while the liquid product is characterized as comprising approx 78 to 87% of the product that are more volatile and evolve below 538° C. The feedstock can be further characterized with approx. 0.1% of its components evolving below 193° C. (naphtha/kerosene fraction), v. approx. 1.3 to 4.8% for the liquid product. The kerosene and diesel fractions also demonstrates significant differences between the feedstock and liquid product with 1% of the feedstock fraction evolving between 193-232° C. v. 2.8 to 5% for the liquid product, and with 8.7% (feedstock) and 18.9 to 23.1% (liquid product) evolving at this temperature range (232-327° C.; diesel). Collectively these results show that a substantial proportion of the components with low volatility in the feedstock have been converted to components of higher volatitly (light naphtha, kerosene and diesel) in the liquid product. These results demonstrate that the liquid product is substantially upgraded, and exhibits properties suitable for transport.
(89) TABLE-US-00014 TABLE 14 Properties and SimDist of liquid products prepared from Bitumen following “Two Stage” processing (reactor temp. 538° C.; for feedstock properties see Tables 1, 8 and 9). Fraction Temp (° C.) R243 Density @ 15.6° C. — 0.9737 API — 13.7 Viscosity @40° C. — 45.4 Light Naphtha <71 0.3 Light/med Naphtha 71-100 0.4 Med Naphtha 100-166 3.6 Naphtha/Kerosne 166-193 1.9 Kerosene 193-232 4.4 Diesel 232-327 19.7 Light VGO 327-360 9.1 Heavy VGO 360-538 41.1 Vacuum Resid. >538 19.5
(90) Under these run conditions the API increased from 8.6 to about 14. A product yield of 68.4 (wt %) was obtained along with greatly reduced viscosity levels (from 30380 cSt @40° C. in the feedstock, to approx. 45 cSt in the liquid product).
(91) Simulated distillation analysis demonstrates that over 50% of the components within the feedstock evolve at temperatures above 538° C. (vacuum resid fraction) while 80.5% of the liquid product evolves below 538° C. The feedstock can be further characterized with approx. 0.1% of its components evolving below 193° C. (naphtha/kerosene fraction), v. 6.2% for the liquid product. The diesel fraction also demonstrates significant differences between the feedstock and liquid product with 8.7% (feedstock) and 19.7% (liquid product) evolving at this temperature range (232-327° C.). Collectively these results show that a substantial proportion of the components with low volatility in the feedstock have been converted to components of higher volatitly (light naphtha, kerosene and diesel) in the liquid product. These results demonstrate that the liquid product is substantially upgraded, and exhibits properties suitable for transport.
(92) All citations are herein incorporated by reference.
(93) The present invention has been described with regard to preferred embodiments. However, it will be obvious to persons skilled in the art that a number of variations and modifications can be made without departing from the scope of the invention as described herein.