Patent Application
20140021101
This invention relates generally to the field of processing hydrocarbons for pipeline transportation, and more particularly to treating hydrocarbons to reduce viscosity to meet pipeline requirements.
By 2015 the amount of Alberta oil sands bitumen shipped to U.S. refineries will be near 1.44 million barrels per day (Edmonton Journal 2008). This is an energy security issue since U.S. relations with Canada are cordial. Additional heavy oils will come from U.S. enhanced oil recovery production and other imports. The petroleum industry is currently undergoing a major paradigm shift in converting refineries to be able to process the heavier feeds. Alberta bitumens are solids or very viscous materials. To ship these materials in pipelines, a significant decrease in viscosity is required. About 25% by volume light oil diluent or 50% by volume light synthetic crude oil is added to the bitumen to lower the viscosity to meet pipeline specifications (Fan et al. 2009). The mixture of the diluent and heavy bitumen is then shipped to the U.S. to refineries that are capable of processing the Canadian material. The solvent is removed by distillation at the refinery, which is energy intensive. In some cases, diluent is pipelined back to Canada for re-use since there is a limited supply, and the amount of diluent available will limit Canadian bitumen availability (Perry 2002). For example, Enbridge is constructing a pipeline from Chicago to Edmonton to return 180,000 barrels per day of diluent solvent back to Canada (Reuters 2009).
The pericondensed asphaltene component molecules cause association effects in oil since they can be modeled as being surrounded by other molecules of intermediate aromaticity and polarity that act as peptizing agents. This results in associated complexes which act as dispersed particles in the oil, resulting in significant viscosity increases above the viscosity of the base solvent oil. The associated complexes can be broken apart in a reversible manner by heating the oil to temperatures below the point where cracking reactions begin (Storm et al. 1995, 1996). If the asphaltenic components such as highly pericondensed aromatic core material can be freed from peptizing molecules which act as solubilizing agents, they can be selectively adsorbed using sorbents. Selective removal of the most pericondensed aromatic molecules in heavy oil could significantly lower the oil viscosity so that much less, if any diluent would be required for pipeline shipment.
Asphaltenes are defined as a solubility class of associated chemical complexes which precipitate when petroleum is dissolved in a low polarity solvent such as heptane. A wide variety of polar and highly pericondensed aromatic molecules containing sulfur, nitrogen, and oxygen as well as metal complexes containing nickel and vanadium are concentrated in the asphaltenes. Asphaltenes act as the major viscosity builders in oil. In catalytic upgrading processes such as hydrotreating, the presence of these materials can shorten catalyst life. The petroleum industry has developed various deasphaltening processes that involve dissolving oil in an excess of hydrocarbon solvent available in the refinery such as compressed propane, or a liquid aliphatic solvent stream, resulting in asphaltene precipitation. The disadvantage of such processes is the high cost of operation resulting from gas compression or solvent removal.
In prior work we have shown that asphaltene components of petroleum residua can adsorb onto on metal surfaces when the oil is heated to temperatures below the temperature at which pyrolysis cracking reactions begin (<340° C.). More deposits were observed on aluminum metal surfaces as the temperature of residua was increased from 100° C. to 300° C. (Schabron et al. 2001). The resulting asphaltenic material enriched in Ni and V was observed to deposit as dark spots on stainless steel and aluminum surfaces, but not on a non-polar Teflon® surface. This phenomenon appears to be due to the partitioning of the intermediate polarity material surrounding the aromatic asphaltene component molecules into the oil matrix solution, exposing the highly pericondensed aromatic or polar material. The pericondensed aromatic or polar material can flocculate and adhere to the polar metal surface. This is a cause of heat-induced fouling of pipes and heat exchangers in refineries. The concept of using this approach to reduce the viscosity of the original oil was not considered at that time.
A new analytical method called the Asphaltene Determinator™ has been developed and is now in routine use at WR1 (Schabron and Rovani 2008, Schabron et al. 2010, U.S. Pat. No. 7,875,464). The Asphaltene Determinator method involves analytical scale precipitation of asphaltene components from a portion of oil on a column packed with ground inert polytetrafluoroethylene (PTFE) using a heptane mobile phase. The precipitated material is re-dissolved in three steps using solvents of increasing solubility parameter: cyclohexane, toluene, and methylene chloride:methanol (98:2 v:v). The amount of asphaltenes (heptane insolubles) and the Total Pericondensed Aromatic (TPA) content can be determined in less than an hour. It was observed in the development work for the method that glass wool or glass beads strongly adsorbed asphaltene component molecules once they are separated from other peptizing molecules in the oil. This observation of an undesired effect in the analytical method reinforced the concept of the possibility of asphaltene component molecule removal by adsorption onto a sorbent. In addition, the Asphaltene Determinator method was ideally suited to evaluate the efficiency of removal of pericondensed aromatic molecules in solventless deasphaltening experiments conducted for this patent application.
An unexpected result occurred when preparative Asphaltene Determinator separations were conducted on 3 g portions of heptane asphaltenes from unpyrolyzed Lloydminster vacuum residuumn, and Lloydminster vacuum residuum that had been mildly pyrolyzed at 400° C. for 30 minutes (Schabron et al 2010). Although the whole asphaltenes from pyrolyzed Lloydminster vacuum residuum were 99.7 wt. % soluble in methylene chloride, 10.3 wt. % methylene chloride insolubles were isolated from this material in replicate preparative Asphaltene Determinator separations. This material resembles coke and it is highly electrostatic. It consists of highly pericondensed aromatic molecules with few, if any alkyl side chains. This is the most refractory component of oil.
The above results suggest that the highly pericondensed material in oils are solubilized by intermediate polarity peptizing molecules present in the oils, however when these are separated, the highly pericondensed molecules self-associate to form large insoluble pre-coke and coke complexes. The surface energy of the pericondensed material is the highest of any component in oil (Pauli et al. 2005). This and other observations related to heat-induced deposition have led us to consider the possibility that the most pericondensed, viscosity building aromatic structures could be selectively removed from oil by heating or pre-treating the oil and exposing it to high surface energy polar or highly aromatic sorbent material. The resulting oil would be deficient in the most refractory viscosity-building pericondensed aromatic structures and the product oil would be much less viscous than the original oil. The pericondensed material adsorbed to the sorbent possibly could later be desorbed by solvent rinsing, or the whole material could be combusted as a fuel to provide heat for the process. Relatively inexpensive yet highly aromatic materials which might be utilized as sorbent include ground petroleum coke or coal based sorbents.
Asphaltenes can be modeled mathematically to be related to the dispersed phase of suspended particles in a base oil, or solvent phase. The effective size of the suspended particles is due to the presence of peptizing molecules that surround the more aromatic or refractory asphaltene “core” molecules. The effective size of these peptized complexes can be decreased by heating the oil. The relative viscosity of a residuum is affected significantly by the effective volume fraction of suspended particles (Schabron et al. 2001). The heat of interaction of the peptizing molecules with the asphaltene core materials was observed to range from 470-1,600 cal/mol for five residua. A similar value of 1,800 cal/mol was observed for Ratawi vacuum residuum by Storm et al. (1995). These heats of interaction indicate that the peptizing molecules can be reversibly separated from the asphaltene core material by heating a heavy oil or residuum to temperatures below the temperature at which pyrolysis begins (<340° C.). Below pyrolysis temperature, the removal of the peptizing molecules by heating is reversible upon cooling.
Partial removal of asphaltenes can result in a significant decrease in viscosity. For example, up to 98% viscosity reduction of Canadian heavy oils has been observed when different asphaltene components were selectively removed in stages in laboratory asphaltene precipitation experiments using a series of solvent with decreasing solvent strength (Kharrat 2009). Decreasing the effective relative volume of the dispersed phase results in significant viscosity reduction (Storm et al. 1995, 1996).
Results from our prior heat-induced deposition experiments suggest the possibility that the most aromatic and refractory asphaltene component molecules can be removed selectively from a heavy oil by heating the oil to a temperature between 150-300° C. and exposing the heated oil to high surface energy sorbent material. The sorbent surface could then be rinsed with an aromatic solvent and used again to repeat the process. Alternatively, carbon based sorbents could be burned as fuel for the process rather than being rinsed with solvent.
It might be easier to remove the most pericondensed components of asphaltenes from a heavy oil or residuum using a solventless adsorptive process if the oil has been subjected to mild pyrolysis first. Aliphatic side chains that can hinder adsorption will decrease, and the Ni and V content of the asphaltenes will increase relative to the maltenes. Thus, part of the invention includes sorbent-based asphaltene removal from oil that has been subjected to mild pyrolysis. Even if only a portion of the asphaltenes can be removed, if these represent the most pericondensed, aromatic and refractory components, both the viscosity of the oil can be decreased dramatically and the quality of the oil can be increased significantly. If the pyrolysis conditions are kept at a mild level, the formation of double bonds and unstable liquids requiring subsequent hydrogen addition can be minimized.
Another possibility for exposing the asphaltene core materials to allow them to adsorb onto a sorbent is by adding a solvent or chemical additives including acids or bases which partially destabilize the oil to deplete the peptizing molecules surrounding the cores. Maqbool et al. (2011) evaluated the destabilization of the asphaltene microstructure which occurs in crude oil with the addition of relatively small amounts of heptane. Material treated in this or similar manners could subsequently be exposed to a sorbent for selective adsorption of the asphaltene component molecules.
Since asphaltenes are the main viscosity builders, partial removal at the production site could lower the viscosity and decrease the amount of diluent required for pipeline shipment. A cost effective alternative to solvent dilution that provides stable, low viscosity oil would provide a significant energy savings. Viscosity can be reduced by removing relatively small portions of the asphaltenes. This invention describes as novel method for viscosity reduction by selective removal of portions of the most refractory pericondensed aromatic or other types of asphaltene components that act as viscosity builders in the oil. Removal of the components is accomplished by an adsorptive process in which the oil is initially heated or treated by various means and then contacted with sorbent to adsorb portions of the asphaltenic material. The sorbent can be but is not limited to a solid in a fixed bed, a fluidized bed, a surfaced, or a porous membrane. One means of initial treatment is to heat the oil to disrupt the ordered structure and to separate the most aromatic and refractory molecules from peptizing molecules that associate with them to keep them in solution. Another possible treatment is mild pyrolysis. Another possible treatment is to add an amount chemical additive or low polarity or other solvent (polar, aromatic, acid or base) to destabilize the ordered structure but not sufficient to completely precipitate asphaltenes from solution. Combinations of these treatments are also possible. The asphaltenic components are then adsorbed onto a stationary phase material. After treatment, the total amount of diluent required to lower the viscosity would be less that that used without the treatment.
The sorbent can be one with high surface energy that is selective to adsorption of asphaltene component molecules such as highly pericondensed aromatic molecules. Examples of the sorbents which may be particularly useful include but not limited to metals, ceramics, zeolites, clays, silica, limestone, glass, quartz, sand, alumina, or high surface energy carbonaceous materials such as petroleum coke, coal, charcoal, activated carbon, or similar materials. Other stationary phases such as salts or acids or bases might be useful also.
By 2015 the amount of Alberta oil sands bitumen shipped to U.S. refineries will be near 1.44 million barrels per day. This is an energy security issue since U.S. relations with Canada are cordial. Additional heavy oils will come from U.S. enhanced oil recovery production and other imports. The petroleum industry is currently undergoing a major paradigm shift in converting refineries to be able to process the heavier feeds. Alberta bitumens are solids or very viscous materials. To ship these materials in pipelines, a significant decrease in viscosity is required. About 25% by volume light oil diluent or 50% by volume light synthetic crude oil is added to the bitumen to lower the viscosity to meet pipeline specifications. The mixture of the diluent and heavy bitumen is then shipped to the U.S. to refineries that are capable of processing the Canadian material. The solvent is removed by distillation at the refinery, which is energy intensive. In some cases, diluent is pipelined back to Canada for re-use since there is a limited supply.
The pericondensed asphaltene component molecules present in bitumen cause association effects in the oil since they can be modeled as being surrounded by other molecules of intermediate aromaticity and polarity that act as peptizing agents. This results in associated complexes which act as particles in the oil, resulting in significant viscosity increases above the viscosity of the base solvent oil. The associated complexes can be broken apart in a reversible manner by heating the oil to temperatures below the point where cracking reactions begin. Heating exposes the highly pericondensed aromatic core materials by freeing them from peptizing molecules which act as solubilizing agents. The associated complexes can also be destabilized by mild pyrolysis or by adding materials to the oil such as solvents or other chemical additives.
Since asphaltenes are the main viscosity builders, partial removal at the production site could lower the viscosity and decrease the amount of diluent required for pipeline shipment. A cost effective alternative to solvent dilution that provides stable, low viscosity oil would provide a significant energy savings. Viscosity can be reduced by removing relatively small portions of the asphaltenes. This invention describes a novel method for viscosity reduction by selective removal of portions of the most refractory pericondensed aromatic or other types of asphaltene components that act as viscosity builders in the oil. Removal of the components is accomplished by an adsorptive process in which the oil is initially heated or treated by various means and then contacted with sorbent to adsorb portions of the asphaltenic material. The sorbent can be a solid in a fixed bed, a fluidized bed, a surface, or a porous membrane. One means of initial treatment is to heat the oil to disrupt the ordered structure and to separate the most aromatic and refractory molecules from peptizing molecules that associate with them to keep them in solution. Another possible treatment is mild pyrolysis. Another possible treatment is to add an amount of chemical additive or low polarity or other solvent to destabilize the ordered structure but not sufficient to completely precipitate asphaltenes from solution. Combinations of these treatments are also possible. The asphaltenic components are then adsorbed onto a stationary phase material. After treatment, the total amount of diluent required would be less that that used without the treatment.
The sorbent can be one with high surface energy that is selective to adsorption of asphaltene component molecules such as highly pericondensed aromatic molecules. Examples of the sorbents which may be particularly useful include but not limited to metals, ceramics, zeolites, clays, silica, limestone, glass, quartz, sand, alumina, or high surface energy carbonaceous materials such as petroleum coke, coal, charcoal, activated carbon, or similar materials. Other sorbents such as salts or acids or bases might be useful also.
This invention describes a new process for lowering the viscosity of heavy oil by the selective removal of the most pericondensed aromatic or other asphaltenic components from oil using an adsorptive process. This is accomplished by initially treating the oil to destabilize the solvent phase/dispersed phase ordered structure to separate the peptizing molecules from the polar asphaltenic and pericondensed aromatic molecules in the oil. Initial treatment can include heating, mild pyrolysis, and/or addition of a solvent or chemical additive. Once the pericondensed aromatic and polar materials are less peptized, portions of these materials can be selectively adsorbed onto high surface energy solid sorbents such as metals, ceramics, zeolites, clays, silica, limestone, glass, quartz, sand, alumina, or high surface energy carbonaceous materials such as petroleum coke, coal, charcoal, activated carbon, acids, bases, salts, or similar materials. In some cases sorbents can be regenerated using small portions of strong solvent formulations. The potential use of carbon based sorbents is attractive since they can be used as part of the fuel for the process and would not need to be rinsed with solvent to desorb the aromatic material.
Selective asphaltene removal using sorbents as an alternative to solvent precipitation, which is the conventional method, could provide a means by which the required amount of diluent could be significantly decreased for lowering viscosity of heavy oils for shipping them from Canada to U.S. refineries in pipelines. Canadian bitumen shipment to the U.S. in pipelines of 1.44 million barrels per day of containing about 25% (v:v) diluent represents 360,000 barrels per day of diluent that will need to be removed by distillation, requiring about 114,000 BTU per barrel, or total energy consumption of 41 billion BTU per day with corresponding CO2 release of 3,570 tons per day (USDOE 1998). This does not include the costs or manufacturing the diluent or shipping it to the production site. A decrease in the amount of diluent used by implementing a solventless deasphaltening process could result in a significant increase in energy efficiency and decrease in CO2 emissions.
As mentioned earlier, the present invention includes a variety of aspects, which may be combined in different ways. The following descriptions are provided to list elements and describe some of the embodiments of the present invention. These elements are listed with initial embodiments, however it should be understood that they may be combined in any manner and in any number to create additional embodiments. The variously described examples and preferred embodiments should not be construed to limit the present invention to only the explicitly described systems, techniques, and applications. Further, this description should be understood to support and encompass descriptions and claims of all the various embodiments, systems, techniques, methods, devices, and applications with any number of the disclosed elements, with each element alone, and also with any and all various permutations and combinations of all elements in this or any subsequent application.
Initial work was conducted to define elevated temperature asphaltene adsorption for developing a sorbent-based asphaltene removal process for heavy oils and residua that does not involve asphaltene precipitation from the oil. Experiments were performed in an apparatus designed and assembled to perform the sorbent tests at an elevated temperature of 250° C. in an inert gas atmosphere. The apparatus was constructed in a 0.65 cu. Ft. (18.4 L) Thermo Scientific Lindberg/Blue M vacuum oven with a maximum temperature capacity of 260° C. The oven has a sealed chamber equipped with inert gas purge vents. It was purged with ultrapure dry nitrogen at 5 L/min during each experiment, from the heating cycle through the overnight cooling cycle. Vacuum was not used.
An apparatus to conduct two experiments at a time was constructed in the oven chamber (
Tests were conducted to percolate heated residuum through the various sorbents. The two oils used were Lloydminster and Cold Lake vacuum residua. The residua and sorbents were heated to 250° C. Once the oven was turned on, it took 100 minutes to reach 250° C. The oven was maintained at this temperature for 60 minutes, and then the conduit pipe was rotated and the heated oil was poured into the heated sorbent. The oil was separated from the sorbent through the medium glass frit filter below the bed of sorbent. Oil that percolated through the sorbent was collected in the glass Petri dish.
The oil was analyzed before and after the sorbent tests using the Asphaltene Determinator to determine if pericondensed asphaltene material was removed by the sorbent. Complex viscosities were measured at 10 rad/sec with a Malvern Kinexus dynamic shear rheometer. Complex viscosity measurements were made at a frequency of 10 Hz at 50° C., which is a pipeline specification temperature, and at 60° C., which is a temperature used for paving asphalt viscosity measurements.
The sorbents tested were 20-4 mesh Caballo lignite coal, 6 mesh glass beads, 70-100 mesh glass beads, 20-40 mesh petroleum coke from a Canadian oil, and size C 316 stainless steel Helipak™ material (small wire coils).
Results from the sorbent tests for Lloydminster vacuum residuum are presented in Table 1 (see
Results from the sorbent tests with Cold Lake residuum are presented in Table 2 (see
The complex viscosity was 1.71 E+7 mPa s for the control that was filtered at 250° C. but without a sorbent. Passing the heated residuum through the stainless steel Helipak sorbent resulted in a complex viscosity of 7.73 E+6 mPa s. This is 54.8% decrease from the original residuum viscosity. By removing 15% of the asphaltenes by a sorbent-based process (representing only 2.5% of the whole residuum), the viscosity was cut by more than half. A similar effect was observed using petroleum coke as sorbent, where the asphaltene content decreased from 16.78% to 14.97%, which represents removal of 10.8% of the asphaltenes, or 1.81% of the whole oil. The complex viscosity at 60° C. decreased from 1.71 E+7 mPa s for the control to 8.86 E+6 mPa s which represents a 48.2% decrease in viscosity. Similar results were noted for both sizes of glass beads, and to a lesser extent with the coal sorbent.
Mass balances are good for all experiments except for the Lloydminster coal sorbent experiment, in which volatiles loss from the coal were significant. The amount of oil remaining on the sorbent is a function of the gravimetric pouring experiment. The amount retained could be minimized by pumping heated oil through a bed of heated sorbent. Once the sorbent is no longer active, it can be regenerated by rinsing with a small portion of a strong chromatographic extraction solvent such as toluene:ethanol (85:5 v:v) and then re-used. For the carbon-based sorbents, the spent sorbent with adsorbed material could be burned as fuel for the process.
Residua solutions consisting of 22 wt. % heptane and cyclohexane respectively were made for the control Cold Lake poured material and the Cold Lake material that was poured through 70-100 mesh glass bead and Helipak stainless steel sorbents, respectively. Complex viscosities were measured for these solutions at 19° C. The results are shown in Table 3 (see
These results are significant since one goal of the current invention is to develop a process to decrease the amount of diluent required to transport Canadian bitumen to U.S. refineries by pipeline. The effect of the removal of a small portion of the most refractory asphaltene materials is to allow less diluent to be used relative to untreated material to achieve a desired lower viscosity. The experiments described above were conducted with vacuum residua. These are significantly more viscous than the actual Canadian bitumens, which are atmospheric 350° C.+residua materials.
Viscosity and Asphaltene Determinator data were evaluated from Canadian Athabasca bitumen sorbent pouring experiments conducted at 150, 200, and 250° C. using three sorbents: glass beads, petroleum coke, and stainless steel Helipak wire. Since the bitumen is an atmospheric residuum, unlike a vacuum residuum, it contains volatile components that can be lost in open vessel elevated temperature experiments.
The viscosity of the whole bitumen is 18.2 Pa s and 9.11 Pa S at 50 and 60° C., respectively. The corresponding dynamic viscosities of the heptane maltenes following gravimetric removal of the 11.8 wt. % gravimetric heptane asphaltenes are 1.43 and 0.697 Pa s at 50 and 60° C., respectively. This reflects a 92% decrease in viscosity at 60° C. by removing the asphaltenes, which is similar in magnitude to the results reported by Kharrat (2009) using asphaltene removal by solvent precipitation. The effect of asphaltene removal from this material on viscosity is significant. Dynamic viscosities at 50 and 60° C. of the original bitumen and the bitumen poured through the sorbents at 150, 200, and 250° C. are provided in Table 4 (see
The Asphaltene Determinator separation results for the original bitumen are provided in Table 5 (see
In accordance with particular descriptions provided herein, certain embodiments of the inventive technology may be described as a hydrocarbon viscosity reduction method that comprises the steps of: treating a hydrocarbon having asphaltenes therein (as a component of the hydrocarbon) to generate a treated hydrocarbon, wherein the hydrocarbon has a first viscosity; contacting the treated hydrocarbon with a sorbent (whether as a result of pouring or other means); and adsorbing at least a portion of the asphaltenes onto the sorbent, thereby removing the at least a portion of the asphaltenes from the hydrocarbon so as to generate a viscosity reduced hydrocarbon having a second viscosity that is lower than the first viscosity.
The term hydrocarbon may include, but is not necessarily limited to, bitumen, shale oil, coal oil, coal tar, biological oil, heavy oil or residuum. It may be or include atmospheric bitumen or vacuum bitumen. It is note that the sorbent is preferably a solid sorbent, and may be either a stationary phase or fluidized sorbent. Solid sorbents include but are not limited to: fixed bed sorbent, fluidized bed sorbent, surfaced sorbent, porous membrane sorbent, high surface energy sorbent, highly aromatic sorbent, sorbent that is selective to adsorption of asphaltenes, metal sorbent, steel sorbent, steel wire sorbent, steel wire coil sorbent, metal wire sorbent, metal wire coil sorbent, ceramic sorbent, zeolite sorbent, clay sorbent, silica sorbent, limestone sorbent, glass sorbent, mesh glass sorbent, glass bead sorbent, mesh glass bead sorbent, quartz sorbent, sand sorbent, alumina sorbent, and high surface energy carbonaceous material sorbent, salt sorbent, acid sorbent, base sorbent, carbon based sorbent, and high surface energy carbonaceous materials (e.g., petroleum coke, ground petroleum coke, coal-based sorbents, charcoal, activated carbon). It is of note that in the case of carbon based sorbents, such sorbents, after being expended as sorbents, can conveniently be burned as fuel for any heating process or step (including those specifically mentioned herein).
The step of treating a hydrocarbon may involve heating the hydrocarbon to above or below a cracking temperature (any temperature that effects cracking of the hydrocarbon; typically at or above 340 C). Heating of the hydrocarbon may be accomplished, in part or whole, via heating from a heat source that is upstream of the sorbent. Such heating step may be, but need not be, supplemented with heating from the sorbent itself (in such case, the method further includes the step of heating the sorbent to generate a heated sorbent). It is of note that in particular embodiments, the heating of the hydrocarbon may be achieved exclusively by heat transfer from the sorbent. In other words, in practice, regardless of the temperature to which the hydrocarbon is to be raised (i.e., regardless if it is to be cracked, even only partially, or not cracked at all), heating of the hydrocarbon may be accomplished strictly via heating from a source other than the sorbent (e.g., upstream of the sorbent, in a heated vessel, for example), strictly via heating from a heated sorbent, or via combination of the two. In those embodiments where the treated hydrocarbon, upon contact with the sorbent, has been heated via both heat transfer occurring upstream of the sorbent (e.g., in a heating vessel) and heat transfer from the sorbent (via a heated sorbent), the respective temperatures to which the two heating operations raise the hydrocarbon need not be the same. Indeed, the temperature to which a heating vessel upstream of the heated sorbent raises the hydrocarbon may be less than, or greater than, or even equal to, the temperature to which the heated sorbent raises (or lowers) the hydrocarbon. As such, in particular embodiments, the heated sorbent (where heated implies heating to some temperature that is above ambient temperature) may actually cool the hydrocarbon heated upstream of the sorbent (i.e., reduce the temperature it achieved from heating upstream of the sorbent). It is of note that, as mentioned, the steps of treating the hydrocarbon (or at least part of the step of treating the hydrocarbon) may involve contacting the untreated hydrocarbon with the sorbent, particularly in those cracking heat embodiments where the sorbent is at a cracking temperature. The step of contacting the treated hydrocarbon with the sorbent may occur later (perhaps immediately later, such as even fractions of a second later, particularly where the required heating (whether to a cracking temperature or not) is to be supplied entirely by the sorbent), after the sorbent heating effectively treats the hydrocarbon. Further, in those embodiments involving cooling of the hydrocarbon, the hydrocarbon that contacts the sorbent, whether heated or not, is still a treated hydrocarbon. It is of further note that heating, regardless of whether the heat source is “upstream” of the sorbent or is the sorbent itself, can utilize any of the well known manners of heating a substance—convection, radiation, conduction, heating element, oven, flame, heated gas, heated liquid, solar, hot solvent, electric, fuel, microwave oven, geothermal, nuclear, external or internal fuel combustion, heating coil, burning deposited material from the sorbent, chemical reaction, and friction, etc.
It is of note that in particular dual heating embodiments where the treated hydrocarbon that contacts the heated sorbent is to have been cracked, even if only mildly, one of such temperatures must be a cracking temperature. It is of note that in embodiments where the treated hydrocarbon is a cracked hydrocarbon, the temperature of the treated hydrocarbon (i.e., when it contacts the sorbent), need not be at a cracking temperature (however, in such case, at some point therebefore the hydrocarbon must have been raised to a cracking temperature). Cracking heat treatment embodiments (i.e., irreversible heating embodiments) may, but need not, involve the step of cooling the cracked hydrocarbon to a temperature below a cracking temperature (such that the treated hydrocarbon (i.e., the hydrocarbon as it is when it contacts the sorbent) might not even be at a cracking temperature). This is because the intent of the cracking is to create an irreversibly modified hydrocarbon; even if a cracked hydrocarbon is cooled it will have properties that enhance asphaltene adsorption (in this invention). As mentioned, such cooling can take place, in embodiments where the heat is applied upstream of the sorbent, even where the sorbent is heated (although certainly it could also take in the case where the sorbent is not heated). However, it is of note that in embodiments wherein the treatment of the hydrocarbon before sorbent contact does not involve cracking (i.e., reversible heating embodiments), the temperature of the treated hydrocarbon (in such case, merely a heated (and not cracked) hydrocarbon) should never have reached a cracking temperature, and upon contact with the sorbent, should be elevated sufficiently above ambient but below a minimum cracking temperature.
Any embodiments, whether involving heating of the hydrocarbon or not, may further comprise the step of rinsing the sorbent with an aromatic solvent after asphaltene adsorption, in order to cleanse the sorbent and prepare it for additional runs. In particular embodiments, the aromatic solvent may be a strong chromatographic extraction solvent such as a halogenated solvent, an aromatic solvent, an alcohol, or a mixture thereof.
In embodiments where treatment involves heating (whether with or without a supplemental solvent/chemical additive addition step further described below), the step of heating the hydrocarbon occurs for a heating time, and such time may be optimized (perhaps minimized). In such manner, energy efficient/environmental pollutant emissions reduction benefits may be realized. Another additional benefit attendant the inventive methods is a reduction of the amount of subsequent hydrogen addition required due to the formation of double bonds and unstable liquids; this benefit may be most pronounced in the case of mild pyrolysis. Further, sorbent contact times may be optimized (lowered to a minimum amount necessary to achieve a desired amount of asphaltene adsorption), to enhance process efficiency.
It is of note that while certain hydrocarbon treatment embodiments that involve heating may be solventless, some may be supplemented with addition of a solvent or chemical additive. Indeed, treatment of the hydrocarbon may, in some embodiments, may be entirely heat free, and be accomplished exclusively with solvent and/or chemical additive addition to an untreated hydrocarbon to generate a treated hydrocarbon that, upon contact with an appropriate sorbent, will have at least some asphaltenes adsorbed thereto. In particular embodiments, the solvent may be a low polarity solvent; whether it be conventionally referred to as a solvent or a chemical additive, it may be a polar material, an aromatic material, or and an acid or base (as but a few characterizations). Preferably, addition of the substance does not effect asphaltene precipitation.
The step of adsorbing at least a portion of the asphaltenes onto the sorbent may comprise the step of adsorbing at least a portion of the most pericondensed aromatic structures of the hydrocarbon, the most pericondensed, aromatic and refractory structures of the hydrocarbon, and/or the most pericondensed and highest surface energy pre-coke asphaltene materials.
The method may further comprise the step of adding a diluent amount to the viscosity reduced hydrocarbon so as to generate a diluted hydrocarbon having a diluted hydrocarbon viscosity that is no greater than a certain viscosity (e.g., a viscosity governed by pipeline specifications, such as a maximum viscosity allowable for hydrocarbons to be pumped through the pipeline). The diluent amount is preferably less than that untreated hydrocarbon diluent amount required to reduce viscosity of an untreated hydrocarbon to the diluted hydrocarbon viscosity.
In particular embodiments, another aspect of the inventive technology may be described as a new method for transporting a hydrocarbon, comprising the steps of: treating an untreated hydrocarbon to generate a treated hydrocarbon, and thereby lowering viscosity of the untreated hydrocarbon to a treated hydrocarbon viscosity; adding an amount of diluent to the treated hydrocarbon to generate a diluted hydrocarbon, thereby further lowering the treated hydrocarbon viscosity to a pipeline specification viscosity, wherein the amount of diluent is less than a conventional amount of diluent required to reduce the viscosity of the untreated hydrocarbon to the pipeline specification viscosity; and pumping the diluted hydrocarbon. The step of treating an untreated hydrocarbon may comprise the step of removing at least a portion of asphaltenes from the untreated hydrocarbon. This may be done via any of the methods specifically described herein. The amount of diluent may be a weight percentage of diluent for a given weight of treated hydrocarbon, while the conventional amount of diluent may be a weight percentage of diluent for a given weight of untreated hydrocarbon. It is of note that the pipeline specification viscosity may be the maximum viscosity allowable for hydrocarbons to be pumped through the pipeline. The method may further comprise the step of removing the diluent from the diluted hydrocarbon (after transport via pumping). It is of note that required diluent reduction may effect a reduction in greenhouse gas emissions (if only because less energy is required to eliminate the reduced amount of diluent from the post-transit hydrocarbon). Reduced diluent requirements may also result in reduced hydrocarbon piping costs, and increased hydrocarbon transportation operation efficiencies.
As can be easily understood from the foregoing, the basic concepts of the present invention may be embodied in a variety of ways. It involves both heating techniques as well as devices to accomplish the appropriate heating. In this application, the heating techniques are disclosed as part of the results shown to be achieved by the various devices described and as steps which are inherent to utilization. They are simply the natural result of utilizing the devices as intended and described. In addition, while some devices are disclosed, it should be understood that these not only accomplish certain methods but also can be varied in a number of ways. Importantly, as to all of the foregoing, all of these facets should be understood to be encompassed by this disclosure.
The discussion included in this application is intended to serve as a basic description. The reader should be aware that the specific discussion may not explicitly describe all embodiments possible; many alternatives are implicit. It also may not fully explain the generic nature of the invention and may not explicitly show how each feature or element can actually be representative of a broader function or of a great variety of alternative or equivalent elements. Again, these are implicitly included in this disclosure. Where the invention is described in device-oriented terminology, each element of the device implicitly performs a function. Apparatus claims may not only be included for the device described, but also method or process claims may be included to address the functions the invention and each element performs. Neither the description nor the terminology is intended to limit the scope of the claims that will be included in any subsequent patent application.
It should also be understood that a variety of changes may be made without departing from the essence of the invention. Such changes are also implicitly included in the description. They still fall within the scope of this invention. A broad disclosure encompassing both the explicit embodiment(s) shown, the great variety of implicit alternative embodiments, and the broad methods or processes and the like are encompassed by this disclosure and may be relied upon when drafting the claims for any subsequent patent application. It should be understood that such language changes and broader or more detailed claiming may be accomplished at a later date (such as by any required deadline) or in the event the applicant subsequently seeks a patent filing based on this filing. With this understanding, the reader should be aware that this disclosure is to be understood to support any subsequently filed patent application that may seek examination of as broad a base of claims as deemed within the applicant's right and may be designed to yield a patent covering numerous aspects of the invention both independently and as an overall system.
Further, each of the various elements of the invention and claims may also be achieved in a variety of manners. Additionally, when used or implied, an element is to be understood as encompassing individual as well as plural structures that may or may not be physically connected. This disclosure should be understood to encompass each such variation, be it a variation of an embodiment of any apparatus embodiment, a method or process embodiment, or even merely a variation of any element of these. Particularly, it should be understood that as the disclosure relates to elements of the invention, the words for each element may be expressed by equivalent apparatus terms or method terms—even if only the function or result is the same. Such equivalent, broader, or even more generic terms should be considered to be encompassed in the description of each element or action. Such terms can be substituted where desired to make explicit the implicitly broad coverage to which this invention is entitled. As but one example, it should be understood that all actions may be expressed as a means for taking that action or as an element which causes that action. Similarly, each physical element disclosed should be understood to encompass a disclosure of the action which that physical element facilitates. Regarding this last aspect, as but one example, the disclosure of a “heater” should be understood to encompass disclosure of the act of “heating”—whether explicitly discussed or not—and, conversely, were there effectively disclosure of the act of “heating”, such a disclosure should be understood to encompass disclosure of a “heater” and even a “means for heating” Such changes and alternative terms are to be understood to be explicitly included in the description. Further, each such means (whether explicitly so described or not) should be understood as encompassing all elements that can perform the given function, and all descriptions of elements that perform a described function should be understood as a non-limiting example of means for performing that function.
Any patents, publications, or other references mentioned in this application for patent are hereby incorporated by reference. Any priority case(s) claimed by this application is hereby appended and hereby incorporated by reference. In addition, as to each term used it should be understood that unless its utilization in this application is inconsistent with a broadly supporting interpretation, common dictionary definitions should be understood as incorporated for each term and all definitions, alternative terms, and synonyms such as contained in the Random House Webster's Unabridged Dictionary, second edition are hereby incorporated by reference. Finally, all references listed in the list of references below or other information statement filed with the application are hereby appended and hereby incorporated by reference, however, as to each of the above, to the extent that such information or statements incorporated by reference might be considered inconsistent with the patenting of this/these invention(s) such statements are expressly not to be considered as made by the applicant(s).
Thus, the applicant(s) should be understood to have support to claim and make a statement of invention to at least: i) each of the viscosity reduction devices as herein disclosed and described, ii) the related methods disclosed and described, iii) similar, equivalent, and even implicit variations of each of these devices and methods, iv) those alternative designs which accomplish each of the functions shown as are disclosed and described, v) those alternative designs and methods which accomplish each of the functions shown as are implicit to accomplish that which is disclosed and described, vi) each feature, component, and step shown as separate and independent inventions, vii) the applications enhanced by the various systems or components disclosed, viii) the resulting products produced by such systems or components, ix) each system, method, and element shown or described as now applied to any specific field or devices mentioned, x) methods and apparatuses substantially as described hereinbefore and with reference to any of the accompanying examples, xi) an apparatus for performing the methods described herein comprising means for performing the steps, xii) the various combinations and permutations of each of the elements disclosed, xiii) each potentially dependent claim or concept as a dependency on each and every one of the independent claims or concepts presented, and xiv) all inventions described herein.
With regard to claims whether now or later presented for examination, it should be understood that for practical reasons and so as to avoid great expansion of the examination burden, the applicant may at any time present only initial claims or perhaps only initial claims with only initial dependencies. The office and any third persons interested in potential scope of this or subsequent applications should understand that broader claims may be presented at a later date in this case, in a case claiming the benefit of this case, or in any continuation in spite of any preliminary amendments, other amendments, claim language, or arguments presented, thus throughout the pendency of any case there is no intention to disclaim or surrender any potential subject matter. It should be understood that if or when broader claims are presented, such may require that any relevant prior art that may have been considered at any prior time may need to be re-visited since it is possible that to the extent any amendments, claim language, or arguments presented in this or any subsequent application are considered as made to avoid such prior art, such reasons may be eliminated by later presented claims or the like. Both the examiner and any person otherwise interested in existing or later potential coverage, or considering if there has at any time been any possibility of an indication of disclaimer or surrender of potential coverage, should be aware that no such surrender or disclaimer is ever intended or ever exists in this or any subsequent application. Limitations such as arose in Hakim v. Cannon Avent Group, PLC, 479 F.3d 1313 (Fed. Cir 2007), or the like are expressly not intended in this or any subsequent related matter. In addition, support should be understood to exist to the degree required under new matter laws—including but not limited to European Patent Convention Article 123(2) and United States Patent Law 35 USC 132 or other such laws—to permit the addition of any of the various dependencies or other elements presented under one independent claim or concept as dependencies or elements under any other independent claim or concept. In drafting any claims at any time whether in this application or in any subsequent application, it should also be understood that the applicant has intended to capture as full and broad a scope of coverage as legally available. To the extent that insubstantial substitutes are made, to the extent that the applicant did not in fact draft any claim so as to literally encompass any particular embodiment, and to the extent otherwise applicable, the applicant should not be understood to have in any way intended to or actually relinquished such coverage as the applicant simply may not have been able to anticipate all eventualities; one skilled in the art, should not be reasonably expected to have drafted a claim that would have literally encompassed such alternative embodiments.
Further, if or when used, the use of the transitional phrase “comprising” is used to maintain the “open-end” claims herein, according to traditional claim interpretation. Thus, unless the context requires otherwise, it should be understood that the term “comprise” or variations such as “comprises” or “comprising”, are intended to imply the inclusion of a stated element or step or group of elements or steps but not the exclusion of any other element or step or group of elements or steps. Such terms should be interpreted in their most expansive form so as to afford the applicant the broadest coverage legally permissible. The use of the phrase, “or any other claim” is used to provide support for any claim to be dependent on any other claim, such as another dependent claim, another independent claim, a previously listed claim, a subsequently listed claim, and the like. As one clarifying example, if a claim were dependent “on claim 20 or any other claim” or the like, it could be re-drafted as dependent on claim 1, claim 15, or even claim 25 (if such were to exist) if desired and still fall with the disclosure. It should be understood that this phrase also provides support for any combination of elements in the claims and even incorporates any desired proper antecedent basis for certain claim combinations such as with combinations of method, apparatus, process, and the like claims.
Finally, any claims set forth at any time are hereby incorporated by reference as part of this description of the invention, and the applicant expressly reserves the right to use all of or a portion of such incorporated content of such claims as additional description to support any of or all of the claims or any element or component thereof, and the applicant further expressly reserves the right to move any portion of or all of the incorporated content of such claims or any element or component thereof from the description into the claims or vice-versa as necessary to define the matter for which protection is sought by this application or by any subsequent continuation, division, or continuation-in-part application thereof, or to obtain any benefit of, reduction in fees pursuant to, or to comply with the patent laws, rules, or regulations of any country or treaty, and such content incorporated by reference shall survive during the entire pendency of this application including any subsequent continuation, division, or continuation-in-part application thereof or any reissue or extension thereon.
This is an international, PCT application and claims priority to U.S. Provisional Application No. 61/450,515, filed Mar. 8, 2011, the provisional application incorporated herein in its entirety.
This invention was made with government support under DOE Contract DE-FC26-08NT43293 awarded by the Department of Energy. The government has certain rights in the invention.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/US12/21317 | 1/13/2012 | WO | 00 | 9/20/2013 |
| Number | Date | Country | |
|---|---|---|---|
| 61450515 | Mar 2011 | US |
