METHODS OF AND APPARATUSES FOR UPGRADING A HYDROCARBON STREAM INCLUDING A DEOXYGENATED PYROLYSIS PRODUCT

Abstract

Methods of and apparatuses for upgrading a hydrocarbon stream are provided. In an embodiment, a method of upgrading a hydrocarbon stream includes providing the hydrocarbon stream that includes a deoxygenated pyrolysis product. The hydrocarbon stream also includes a residual oxygen-containing compound content. The residual oxygen-containing compound content of the hydrocarbon stream is reduced to form an upgraded hydrocarbon stream.

Description

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This invention was made with Government support under ZFT-0-40619-01 awarded by the United States Department of Energy. The Government has certain rights in the invention.

TECHNICAL FIELD

The technical field generally relates to methods of and apparatuses for upgrading a hydrocarbon stream, and more particularly relates to methods of and apparatuses for upgrading a hydrocarbon stream that includes a deoxygenated pyrolysis product.

BACKGROUND

Biofuels encompass various types of combustible fuels that are derived from biomass. Biofuels can be used as combustible fuels themselves, can be used as an additive component of a combustible fuels, or can be co-processed with other hydrocarbon sources, such as a petroleum-based source of hydrocarbons, to produce combustible fuels. Pyrolysis is a commonly-used process for converting biomass into biofuel, and pyrolysis can be conducted through either a thermal process or a catalytic process. In the catalytic pyrolysis process, the biomass is rapidly heated under an inert atmosphere in the presence of a catalyst, such as an acid or zeolitic catalyst, to promote deoxygenation and cracking of pyrolysis vapors into hydrocarbons and oxygen-containing compounds, such as phenol, cresol, and alcohols such as C1 to C4 alcohols. Most of the oxygen-containing compounds can be converted to hydrocarbons during catalytic pyrolysis to produce a deoxygenated pyrolysis product.

Thermal pyrolysis processes include the recently-developed fast pyrolysis process. Fast pyrolysis is a process during which biomass is rapidly heated to about 450° C. to about 600° C. in the absence of air using a pyrolysis unit. Under these conditions, a pyrolysis vapor stream including organic vapors, water vapor, and pyrolysis gases is produced, along with char (which includes ash and combustible carbonaceous solids). A portion of the pyrolysis vapor stream is condensed in a condensing system to produce a pyrolysis oil stream. Pyrolysis oil is a complex, highly oxygenated organic liquid that typically contains about 20-30% by weight water with high acidity (total acid number (TAN)>150). Because the pyrolysis oil contains high amounts of oxygen-containing compounds, deoxygenation unit operations may be employed to remove oxygen-containing compounds from the pyrolysis oil after fast pyrolysis to thereby form a deoxygenated pyrolysis product. For example, hydrotreating is a known deoxygenation unit operation that is commonly used for converting the oxygen-containing compounds present in the pyrolysis oil to produce the deoxygenated pyrolysis product.

Deoxygenated pyrolysis products produced through catalytic pyrolysis and thermal pyrolysis (after deoxygenation) generally contain a residual oxygen-containing compound content. While it would be desirable to use the deoxygenated pyrolysis products in a transportation fuel such as gasoline or kerosene, even small amounts of oxygen-containing compounds can be classified as undesirable contaminants. Hydrotreating of pyrolysis products that include ethanol also converts the ethanol to ethane, which reduces the yield of liquid pyrolysis products. Similarly, hydrotreating can saturate aromatic hydrocarbons, reducing the octane value of the gasoline fraction and consuming excessive amounts of hydrogen. Therefore, while hydrotreating of pyrolysis oil may be effective to remove most of the oxygen-containing compounds from the pyrolysis oil to produce the deoxygenated pyrolysis products, excessive hydrotreating is undesirable to reduce the oxygen-containing compounds to levels that are desirable in gasoline for the deoxygenated pyrolysis products.

Accordingly, it is desirable to provide methods of upgrading a hydrocarbon stream to maximize removal of oxygen-containing compounds that may be present in the hydrocarbon stream. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.

BRIEF SUMMARY

Methods of and apparatuses for upgrading a hydrocarbon stream are provided. In an embodiment, a method of upgrading a hydrocarbon stream includes providing the hydrocarbon stream that includes a deoxygenated pyrolysis product. The hydrocarbon stream also includes a residual oxygen-containing compound content. The hydrocarbon stream that includes the residual oxygen-containing compound content is contacted with a solvent composition that has a greater affinity for oxygen-containing compounds over hydrocarbons to reduce the residual oxygen-containing compound content of the hydrocarbon stream.

Another embodiment of a method of upgrading a hydrocarbon stream includes pyrolyzing a biomass feed to produce a pyrolysis product stream. The pyrolysis product stream or a derivative thereof is contacted with a solvent composition that has a greater affinity for oxygen-containing compounds over hydrocarbons. A spent solvent composition is separated from an upgraded hydrocarbon stream after contacting the hydrocarbon stream with the solvent composition.

In another embodiment, an apparatus for upgrading a hydrocarbon stream includes a pyrolysis unit for pyrolyzing a biomass feed to produce a pyrolysis product stream. The apparatus optionally includes a deoxygenating unit for receiving the pyrolysis product stream and for deoxygenating the pyrolysis product stream. An extraction unit is downstream of the optional deoxygenating unit for receiving the hydrocarbon stream that includes a deoxygenated pyrolysis product. The extraction unit extracts residual oxygen-containing compounds from the hydrocarbon stream.

BRIEF DESCRIPTION OF THE DRAWINGS

The various embodiments will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein:

FIG. 1 is a schematic diagram of an apparatus for and a method of upgrading a hydrocarbon stream in accordance with an exemplary embodiment;

FIG. 2 is a schematic diagram of a catalytic pyrolysis unit that is included in the apparatus of FIG. 1 in accordance with an embodiment;

FIG. 3 is a schematic diagram of an extraction unit that is included in the apparatus of FIG. 1 in accordance with an embodiment;

FIG. 4 is a schematic diagram of an apparatus for and a method of upgrading a hydrocarbon stream in accordance with another exemplary embodiment;

FIG. 5 is a schematic diagram of a thermal pyrolysis unit that is included in the apparatuses of FIG. 1 or FIG. 4 in accordance with an embodiment; and

FIG. 6 is a schematic diagram of an apparatus for and a method of upgrading a hydrocarbon stream, with the apparatus including a co-processing unit in accordance with another embodiment.

DETAILED DESCRIPTION

The following detailed description is merely exemplary in nature and is not intended to limit the various embodiments or the application and uses thereof. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description.

Methods of and apparatuses for upgrading a hydrocarbon stream that includes a deoxygenated pyrolysis product are provided herein. In accordance with the methods and apparatuses described herein, the hydrocarbon stream that includes the deoxygenated pyrolysis product is upgraded to reduce residual oxygen-containing compound content, if the hydrocarbon stream includes any residual oxygen-containing compound, through a downstream unit operation beyond deoxygenation unit operations or intrinsic deoxygenation that may be employed to yield the deoxygenated pyrolysis product. As referred to herein, “deoxygenated pyrolysis product” refers to any component in the hydrocarbon stream that originates from pyrolysis and that has undergone a unit operation that removes at least a portion of oxygen-containing compounds therefrom. The deoxygenated pyrolysis product may be provided as a direct pyrolysis product stream or a derivative of the pyrolysis product stream that is obtained after subjecting the pyrolysis product stream to further unit operations. For example, the deoxygenated pyrolysis product can be a direct product of pyrolysis (such as catalytic pyrolysis) or can be a product that results from a downstream unit operation after pyrolysis, such as for example a fractionation column that is downstream of the pyrolysis unit or a deoxygenating unit that is downstream of a thermal pyrolysis unit. Further, the hydrocarbon stream can be the product of a co-processing unit operation such as, for example, a fluid catalytic cracking (FCC) unit operation, within which a pyrolysis product stream is co-processed or catalytically cracked with another source of hydrocarbons such as a petroleum-based source of hydrocarbons. The hydrocarbon stream that includes the deoxygenated pyrolysis product may be upgraded by contacting the hydrocarbon stream with a solvent composition that has a greater affinity for oxygen-containing compounds over hydrocarbons. Contacting the hydrocarbon stream with the solvent composition is effective to reduce any residual oxygen-containing compound content of the hydrocarbon stream without diminishing inherent fuel properties of the hydrocarbon stream or increasing production costs.

An embodiment of a method of upgrading a hydrocarbon stream 20 will now be addressed with reference to an exemplary apparatus 10 for upgrading the hydrocarbon stream 20 as shown in FIG. 1, with further reference to FIGS. 2 and 3 that show additional features of an exemplary pyrolysis unit 12 and an exemplary extraction unit 14 of the apparatus 10 shown in FIG. 1.

Referring to FIG. 1, the apparatus 10 includes the pyrolysis unit 12 and the extraction unit 14. The pyrolysis unit 12 receives a biomass feed 18 and pyrolyzes the biomass feed 18 to produce a pyrolysis product stream. In the embodiment of FIG. 1, no intervening deoxygenating unit is disposed between the pyrolysis unit 12 and the extraction unit 14, although in other embodiments and referring momentarily to FIG. 4, a deoxygenating unit 416 may be disposed between a pyrolysis unit 412 and the extraction unit 14, with the deoxygenating unit 416 in fluid communication with the pyrolysis unit 412 and the extraction unit 14 and with the extraction unit 14 downstream of the deoxygenating unit 416. It is to be appreciated that in other embodiments and although not shown, the pyrolysis unit may be located at a remote satellite location from the optional deoxygenation unit and the extraction unit. The presence or absence of the deoxygenating unit may be dependent upon the type of pyrolysis unit that is included in the apparatus. In particular, in the embodiment of FIG. 1 and as shown in further detail in FIG. 2, the pyrolysis unit 12 is a catalytic pyrolysis unit 12 and the apparatus 10 is free from a deoxygenating unit downstream of the pyrolysis unit 12 as described in further detail below.

Referring to FIG. 1, the hydrocarbon stream 20 includes a deoxygenated pyrolysis product. It is to be appreciated that although the hydrocarbon stream 20 is shown in the Figures to be produced in accordance with the methods described herein within the apparatuses described herein, in other embodiments, the hydrocarbon stream may be provided from a source external to the methods or apparatuses described herein. The deoxygenated pyrolysis product may be produced through pyrolysis of a biomass feed 18 in the pyrolysis unit 12. Suitable biomass feeds 18 include, but are not limited to, lignocellulosic materials including cellulose, hemicellulose and lignin or portions thereof, such as short rotation forestry products, sawmill residues, forest residues, wood chips, chaff, grains, grasses, agricultural residues such as corn stover and sugar cane bagasse, weeds, aquatic plants such as whole algae and lipid extracted algae, hay, recycled and non-recycled paper and paper products, and any other biogenically-derived material.

In accordance with an embodiment and as shown in FIG. 1, the pyrolysis unit 12 is the catalytic pyrolysis unit 12, which may be a conventional catalytic pyrolysis unit. In catalytic pyrolysis units and referring to FIG. 2, the biomass feed 18 is rapidly heated under an inert atmosphere in the presence of a catalyst 24, such as an acid or zeolitic catalyst, to promote deoxygenation and cracking of pyrolysis vapors into hydrocarbons and oxygen-containing compounds, such as phenol, cresol, and alcohols such as C1 to C4 alcohols. Most of the oxygen-containing compounds can be converted to hydrocarbons in the catalytic pyrolysis unit 12 to produce a deoxygenated pyrolysis product. More specifically, referring to FIG. 2, further details of the catalytic pyrolysis unit 12 are shown. In particular, as shown in FIG. 2, the catalytic pyrolysis unit 12 includes a pyrolysis reactor 26 for pyrolyzing the biomass feed 18, a catalyst regenerator 27 for receiving and regenerating spent catalyst 29, and a distillation column 32 for receiving an intermediate pyrolysis stream 33 from the pyrolysis reactor 26 and for separating various components of the intermediate pyrolysis stream 33 into separate streams 20, 40, 41, and 42. In particular, the biomass feed 18 is catalytically pyrolyzed in the pyrolysis reactor 26 to produce the intermediate pyrolysis stream 33, and the intermediate pyrolysis stream 33 is fractionated into the separate streams 20, 40, 41, and 42 by boiling point in the distillation column. One of the separate streams that is fractionated by the distillation column 32 is the deoxygenated pyrolysis product 20, which may also be identified as a catalytic pyrolysis heavy naptha stream in a conventional catalytic pyrolysis process flow and which ultimately goes to gasoline blendstock. Conventional catalytic pyrolysis heavy naphtha streams are generally characterized by having a gasoline boiling range such as, e.g., of from about 40 to about 200° C., depending upon the environment in which the gasoline blendstock is to be used. For example, the initial boiling point may be adjusted up in winter and down in summer and the final boiling point is adjusted down to meet emission requirements using the reformulated gasoline model. The deoxygenated pyrolysis product 20 is generally depleted of most oxygen-containing compounds that are present in the intermediate pyrolysis stream 33, although the deoxygenated pyrolysis product 20 may have a residual oxygen-containing compound content. For example, the deoxygenated pyrolysis product 20 may have a residual oxygen-containing compound content of less than about 15 weight %, such as from about 0.01 to about 10 weight %, such as from about 1 to about 3 weight %, based on the total weight of the deoxygenated pyrolysis product 20. Residual oxygen-containing compounds that may be present in the deoxygenated pyrolysis product include, but are not limited to, ketones, carboxylic acids, aldehydes, esters, phenols, furans, and multi-oxygenated compounds. Because the deoxygenated pyrolysis product 20 is depleted of most oxygen-containing compounds, in an embodiment and as shown in FIG. 1, the apparatus 10 is free from the deoxygenating unit. In this embodiment, the deoxygenated pyrolysis product 20 is provided as the hydrocarbon stream 20 for further downstream processing, as described in further detail below.

Referring back to FIG. 1, in accordance with the exemplary method, the residual oxygen-containing compound content of the hydrocarbon stream 20 is contacted with a solvent composition 44 that has a greater affinity for oxygen-containing compounds over hydrocarbons. The hydrocarbon stream 20 may be contacted with the solvent composition 44 through various unit operations that are known to separate oxygen-containing compounds from a hydrocarbon stream 20. By “greater affinity”, it is meant that when the solvent composition 44 and the hydrocarbon stream 20 are in contact with each other at equilibrium, the concentration of oxygen-containing compounds in the solvent 44 is much higher than their concentration in the hydrocarbon stream 20. In embodiments, the solvent composition 44 has a higher density than the hydrocarbon stream 20 to enable liquid/liquid extraction techniques to be employed as described in further detail below. Suitable solvent compositions 44 that may be employed to contact the hydrocarbon stream 20 include, but are not limited to, basic solvents and/or organic solvents. Examples of suitable solvent compositions 44 include, but are not limited to, water made basic by addition of a basic compound such as ammonia, soda ash, or the like; sulfolane; glycols such as triethylene glycol; N-methylpyrrolidone; and combinations thereof. Water made basic by addition of ammonia and/or soda ash is selective toward removal of phenol and, thus, serves as a particular suitable solvent composition 44.

Because oxygen-containing compounds to be removed from the hydrocarbon stream 20 are only present in residual amounts, relatively small amounts of the solvent composition 44 compared to the amount of the hydrocarbon stream 20 are required to effectively reduce the residual oxygen-containing compound content of the hydrocarbon stream 20. In an embodiment, the hydrocarbon stream 20 is contacted with the solvent composition 44 at a fraction of the solvent composition 44 to the hydrocarbon stream 20 of from about 2 to about 10% by volume, such as from about 2 to about 6% by volume, based on the total volume of the hydrocarbon stream 20. Such low amounts of the solvent composition 44 to the hydrocarbon stream 20 are particularly suitable when the extraction unit is a mercaptan extraction unit, such as a Merox™ extraction unit commercially available from UOP LLC. Alternatively, in other embodiments and depending upon the type of extraction unit that is employed, the amount of residual oxygen-containing compounds in the hydrocarbon stream 20, and the selectivity of the solvent composition 44, higher fractions of the solvent composition 44 to the hydrocarbon stream 20 may be employed such as a fraction of the solvent composition 44 to the hydrocarbon stream 20 of up to 1000% by volume, such as up to about 500% by volume, based on the total volume of the hydrocarbon stream 20.

In an embodiment and as shown in FIG. 1, the apparatus 10 includes the extraction unit 14 to facilitate contact of the hydrocarbon stream 20 with the solvent composition 44. In the embodiment shown in FIG. 1, the extraction unit 14 is in fluid communication with the pyrolysis unit 12 for receiving the hydrocarbon stream 20 and for extracting residual oxygen-containing compounds from the hydrocarbon stream 20. Although not shown in FIG. 1, it is to be appreciated that intervening units may be disposed upstream of the extraction unit 14, between the pyrolysis unit 12 and the extraction unit 14, to further process the pyrolysis product in accordance with conventional techniques. It is also to be appreciated that the pyrolysis unit and the extraction unit need not necessarily be in fluid communication.

In an embodiment, the hydrocarbon stream 20 is in a liquid phase when contacted with solvent composition 44 in a liquid phase, with oxygen-containing compounds transferred from the hydrocarbon stream 20 to the solvent composition 44. However, an alternative embodiment with the hydrocarbon stream 20 as a gas is also feasible, though the higher temperature required makes it a less attractive option. Referring to FIG. 3, further details of an exemplary extraction unit 14 are shown in accordance with an embodiment. In this embodiment, the extraction unit 14 includes an extraction column 48, a solvent fractionation column 50 in fluid communication with the extraction column 48 for receiving oxygenate-rich solvent composition 52, and a condenser 54 in fluid communication with the solvent fractionation column 50 for receiving an oxygenate-lean solvent stream 56. In this embodiment, the extraction unit 14 provides for recovery of the oxygenate-rich solvent composition 52 for further use within the extraction unit 14. The extraction column 48 may facilitate liquid/liquid contact and, in an embodiment, is specifically designed for a low flow rate of the solvent composition 44. During operation, the hydrocarbon stream 20 is introduced into the extraction column 48 in liquid phase and the solvent composition 44 is introduced into the extraction column 48 in liquid phase, with the hydrocarbon stream 20 introduced into a bottom of the extraction column 48 and the solvent composition 44 introduced into a top of the extraction column 48. In an exemplary embodiment and as shown in FIG. 3, the extraction column 48 includes a series of trays 55 that each include a weir 57 that is adapted to receive the solvent composition 44 from higher trays 55, with downcomers 58 extending from a weir 57 of higher trays 55 to a weir 57 of the immediately adjacent lower trays 55 and with the weirs 57 providing a sufficient depth to maintain a level of the solvent composition 44 sufficiently high to seal the downcomers 58 that lead thereinto. The weirs 57 maintain a deep layer (e.g., about 30 cm) of the solvent composition 44 on the trays 55 to ensure adequate liquid/liquid contact between the solvent composition 44 and the hydrocarbon stream 20 in each stage. The weirs 57 seal the downcomers 58 to prevent the hydrocarbon stream 20, which is less dense than the solvent composition 44 in this embodiment, from entering the downcomers 58. In embodiments, the downcomers 58 may be pipes, although at higher solvent composition 44 to hydrocarbon stream 20 flow rates, the downcomers 58 may be conventional chordal baffles instead of pipes. Each tray 55 also includes a perforated jet deck 61 that enables the hydrocarbon stream 20 in liquid form to flow up the extraction column 48, through the trays 55. The perforated jet deck 61 has perforations that are sufficiently small to avoid weeping of the solvent composition 44 in the trays 55 through the perforations during operation of the extraction column 48.

In accordance with an embodiment, an oxygenate-rich solvent composition 52 is separated in the liquid phase from an upgraded hydrocarbon stream 21 in the liquid phase after contacting the hydrocarbon stream 20 with the solvent composition 44. For example, as shown in FIG. 3, the oxygenate-rich solvent composition 52 may be collected in the extraction column 48 and removed from a bottom of the extraction column 48, while the hydrocarbon stream 20 that is passed through the trays 55 of the extraction column 48 becomes upgraded through the contact with the solvent composition 44 and exits the extraction column 48 at a top thereof. The upgraded hydrocarbon stream 21 may be used as transportation fuel, or may be subject to further unit operations in accordance with conventional hydrocarbon refinement. The oxygenate-rich solvent composition 52 may be regenerated to produce an oxygen-containing compound stream 63 and the oxygenate-lean solvent stream 56. For example, in an embodiment and as shown in FIG. 3, the oxygenate-rich solvent composition 52 is introduced into the solvent fractionation column 50, which fractionates the oxygenate-rich solvent composition 52 into the oxygenate-lean solvent stream 56 in vapor form and the oxygen-containing compound stream 63 in liquid form. The oxygen-containing compound stream 63 is expelled to waste, remediation, or recovery of the oxygen-containing compounds therein. The oxygenate-lean solvent stream 56 in vapor form is passed to the condenser 54 to condense the oxygenate-lean solvent stream 56 into liquid form. However and although not shown, it is to be appreciated that in other embodiments, a higher boiling solvent composition could be used, in which case the oxygenate-containing compound stream would be recovered overhead and the oxygenate-lean solvent stream would be recovered from the bottom of the condenser. In an embodiment, some oxygen-containing compounds may remain in the oxygenate-lean solvent stream 56 and, to avoid buildup within the extraction unit 14, the oxygenate-lean solvent stream 56 is separated into a drag stream 69 and a recycle stream 71. The recycle stream 71 is combined with fresh solvent composition 73 and returned to the extraction column 48.

In another embodiment and although not shown, it is to be appreciated that the extraction unit may only include the extraction column, without the further features that provide for recovery of the solvent composition. In this embodiment, the oxygenate-rich solvent composition may be expelled to waste or remediation without recovery of the solvent composition.

Another embodiment of a method of upgrading a hydrocarbon stream will now be addressed with reference to an exemplary apparatus 410 for upgrading the hydrocarbon stream 420 as shown in FIG. 4, with further reference to FIG. 5 that shows additional features of an exemplary pyrolysis unit 412 of the apparatus 410 shown in FIG. 4. Referring to FIG. 4 and as alluded to above, in an embodiment the apparatus 410 includes the pyrolysis unit 412, the deoxygenating unit 416, and the extraction unit 14 that is in fluid communication with the pyrolysis unit 412. In this embodiment, the pyrolysis unit 412 is a thermal pyrolysis unit 412 and produces pyrolysis oil 433, which is highly oxygenated. Conversely, the catalytic pyrolysis unit 12 of the embodiment shown in FIG. 1 produces deoxygenated pyrolysis products 20. The deoxygenating unit 416 may be disposed between the pyrolysis unit 412 and the extraction unit 14 to remove most oxygen-containing compounds from the pyrolysis oil 433 before introducing into the extraction unit 14, with the deoxygenating unit 416 in fluid communication with the pyrolysis unit 412 and the extraction unit 14 and with the extraction unit 14 downstream of the deoxygenating unit 416. The extraction unit 14 in this embodiment may be the same as described above.

Referring to FIG. 4, the hydrocarbon stream 420 includes a deoxygenated pyrolysis product. In this embodiment, the deoxygenated pyrolysis product may be produced through thermal pyrolysis of a biomass feed 18, such as in the thermal pyrolysis unit 412. In this embodiment, thermal pyrolysis produces the pyrolysis product stream 433, which is pyrolysis oil 433. The pyrolysis product stream 433 is then deoxygenated in the deoxygenating unit 416. Suitable biomass feeds 18 include those described above.

In accordance with an embodiment and as shown in detail in FIG. 5, the thermal pyrolysis unit 412 may be a fast thermal pyrolysis unit 412. In this embodiment, the pyrolysis unit 412 includes a hopper or feed bin 78 for receiving the biomass feed 18. The hopper 78 is in communication with a reactor feed chamber 80 formed by, for example, an auger, a screw feed device, a conveyor, or other batch feed device. The reactor feed chamber 80 is further selectively connected to a thermal conversion or pyrolysis reactor 426 that is configured to thermally convert or pyrolyze the biomass feed 18. The thermal conversion reactor 426 includes a biomass inlet 82 for receiving the biomass feed 18 from the reactor feed chamber 80. Further, the thermal conversion reactor 426 includes a carrier gas inlet 84 for receiving a carrier gas 86. The thermal conversion reactor 426 may also include a solid heat transfer medium inlet 88 to receive hot heat transfer medium 90, such as sand, catalyst, or other inert particulate. Alternatively and although not shown, the heat transfer medium 90 may be mixed with and carried by the carrier gas 86 through the carrier gas inlet 84.

As the biomass feed 18 is heated by the heat transfer medium 90 to a thermal conversion or pyrolysis temperature, typically about 500° C., the thermal conversion or pyrolysis reaction occurs and pyrolysis vapor 92 and char are formed in the thermal conversion reactor 426. The pyrolysis vapor 92 and char, along with the heat transfer medium 90, are carried out of an outlet 96 in the thermal conversion reactor 426 and through a line 98 to a separator 100, such as, for example, a cyclone. The separator 100 separates the pyrolysis vapor 92 from the char and heat transfer medium 94. As shown, the pyrolysis vapor 92 is directed to a pyrolysis condenser 72 which condenses the pyrolysis vapor 92 to form the pyrolysis oil 433. Uncondensed gas 86 exits the pyrolysis condenser 72, a portion of the uncondensed gas 86 may be recycled as the carrier gas 86, and a portion of the uncondensed gas 86 may be taken as net gas product 85. The net gas product 85 may be burned to dry the biomass feed 18 or used as a combustion fuel to generate electricity.

The char and heat transfer medium 94 are fed to a combustion unit 102, typically referred to as a reheater, for the purpose of reheating the heat transfer medium 90. As shown, a blower 104 feeds air or another oxygen-containing gas 106 into the combustion unit 102. Upon contact with the oxygen, the char combusts, heating the heat transfer medium 90 and forming flue gas and ash 108. The hot heat transfer medium 90 exits the combustion unit 102 and is returned to the thermal conversion reactor 426. The flue gas and ash 108 exit the combustion unit 102 and are directed to a flue gas separator 110, such as a cyclone. The flue gas separator 110 separates the ash 112 and the flue gas 114, which can be disposed of.

The pyrolysis product stream from the pyrolysis unit 412, for purposes of this embodiment, is the pyrolysis oil 433. Because the pyrolysis oil 433 is highly oxygenated coming from the thermal pyrolysis unit 412, the pyrolysis product stream 433 is deoxygenated to produce the deoxygenated pyrolysis product 420. One example of a suitable technique for deoxygenating the pyrolysis product stream 433 is hydrotreating, which reduces the oxygen-containing compound content of the pyrolysis product stream 433 thereby producing the deoxygenated pyrolysis product 420. The deoxygenated pyrolysis product 420 generally has a residual oxygen-containing compound content, which is less than the original oxygen-containing compound content of the pyrolysis product stream 433. In an embodiment and as shown in FIG. 4, the pyrolysis product stream 433 is deoxygenated within the deoxygenating unit 416, which may be a hydrotreating unit. Generally, the pyrolysis product stream 433 is in a liquid state and is introduced into the deoxygenating unit 416, which includes a hydrotreating reactor (not shown) having a hydrotreating catalyst bed. In embodiments, the hydrotreating reactor may be a continuous flow reactor, such as a fixed-bed reactor, a continuous stirred tank reactor (CSTR), a trickle bed reactor, an ebulliating bed reactor, a slurry reactor, or any other reactor known to those skilled in the art for hydroprocessing. Conditions for effectuating hydrotreating are known in the art. Deoxygenating produces the deoxygenated pyrolysis product 420 and an oxygen-containing compound stream 435. In this embodiment, the deoxygenated pyrolysis product 420 is provided as the hydrocarbon stream 420 for further downstream processing.

In accordance with the exemplary method, the residual oxygen-containing compound content of the hydrocarbon stream 420 is contacted with the solvent composition 44. In particular, as described above, the hydrocarbon stream 420 may be contacted with the solvent composition 44 as described above to produce the upgraded hydrocarbon stream 421, with the extraction unit 14 being the same as described above.

In another embodiment of a method of upgrading a hydrocarbon stream 620, the hydrocarbon stream 620 is provided by co-processing a pyrolysis product stream 633 and a petroleum-based source of hydrocarbons 637 to produce the hydrocarbon stream 620, as illustrated in FIG. 6. For example, the exemplary method of this embodiment may be conducted in an apparatus 610 that is similar to the apparatuses 10, 410 shown in FIGS. 1 and 4, respectively, but that includes a co-processing unit 613 that is in fluid communication with the pyrolysis unit 612 and the extraction unit 14 and is downstream of the pyrolysis unit 612 and upstream of the extraction unit 14. Referring to FIG. 6, co-processing the pyrolysis product stream 633 and the petroleum-based source of hydrocarbons 637 is conducted by catalytically cracking a mixture 646 of the pyrolysis product stream 633 and the petroleum-based source of hydrocarbons 637 in the presence of a particulate cracking catalyst 630.

Catalytic cracking can be conducted in any manner known in the art for co-processing pyrolysis product streams and petroleum-based sources of hydrocarbons 637, such as in a fluid catalytic cracking (FCC) unit. By way of example and as shown in FIG. 6, an exemplary co-processing unit 613 includes a vertical conduit or riser 628. The petroleum-based source of hydrocarbons 637 is introduced into the riser 628 from a hydrocarbon outlet 638 and the particulate cracking catalyst 630 may be introduced into the riser 628 at a catalyst outlet 631 that is downstream of the hydrocarbon outlet 638 but upstream of a pyrolysis product outlet 636. However, it is to be appreciated that the methods described herein are not particularly limited to the relative locations of the hydrocarbon outlet 638, the catalyst outlet 631, and the pyrolysis product outlet 636. The residence time of the particulate cracking catalyst 630 and the mixture 646 of the pyrolysis product stream 633 and the petroleum-based source of hydrocarbons 637 in the riser 628 is generally only a few seconds. General operating conditions within the riser 628 in co-processing units 613 are known in the art, e.g., a reaction temperature is generally from about 510 to about 565° C., reaction pressure of about 135 to about 280 kPa, and a ratio of catalyst to the mixture 646 of the pyrolysis product stream 633 and the petroleum-based source of hydrocarbons 637 of from about 4:1 to about 12:1.

Catalytic cracking of the mixture 646 of the pyrolysis product stream 633 and the petroleum-based source of hydrocarbons 637 produces an effluent 659 that includes spent particulate cracking catalyst 676 and a gaseous component 661. The gaseous component 661 includes products from the reaction in the riser 628 such as cracked hydrocarbons. In accordance with an embodiment of the contemplated method, the spent particulate cracking catalyst 676 and the gaseous component 661 are separated. In this embodiment, and as shown in FIG. 6, the co-processing unit 613 further includes a containment vessel 662 that separates the spent particulate cracking catalyst 676 from the effluent 659. The gaseous component 661 of the effluent 659 is separated from the spent particulate cracking catalyst 676 in the separator vessel 662, and the gaseous component 661 may be vented from the separator vessel 662 via a product line 660. Various separation schemes are known in the art for separating the spent particulate catalyst 676 and the gaseous component 661. In an embodiment, bulk separation is accomplished by passing the effluent 659 through a tee disengage 647, followed by passing the effluent through a primary cyclone 649 and secondary cyclone 651 to complete the separation. Although multiple sets of cyclones are generally used, only one set of the primary cyclone 649 and the secondary cyclone 651 is shown. The spent particulate cracking catalyst 676 falls downward to a stripper 668, where stripping steam 645 is introduced and combined with the spent particulate cracking catalyst 676. A catalyst regenerator 670 is in fluid communication with the separator vessel 662 and with the riser 628. The spent particulate cracking catalyst 676 that is separated from the gaseous component 661 is introduced into the catalyst regenerator 670 from the stripper 668, and coke is removed from the spent particulate cracking catalyst 676 in the catalyst regenerator 670. The catalyst regenerator 670 passes regenerated particulate catalyst 630 to the riser 628.

It is to be appreciated that, although not shown in FIG. 6, the deoxygenating unit may be included in the apparatus 610 of FIG. 6, either upstream or downstream of the co-processing unit. It is also to be appreciated that in embodiments, no deoxygenating unit is necessary for the apparatus 610 of FIG. 6. The gaseous component 661 may be condensed in a condenser 664 and introduced into a distillation column 632, where distillation may be conducted in the same manner as described above in the context of the embodiment shown in FIG. 2 to provide the hydrocarbon stream 620 that is ultimately passed to the extraction unit 14.

While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the invention. It being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims.

Claims

1. A method of upgrading a hydrocarbon stream, the method comprising the steps of:

providing the hydrocarbon stream comprising a deoxygenated pyrolysis product, wherein the hydrocarbon stream comprises a residual oxygen-containing compound content; and

contacting the hydrocarbon stream with a solvent composition that has a greater affinity for oxygen-containing compounds over hydrocarbons to reduce the residual oxygen-containing compound content of the hydrocarbon stream.

2. (canceled)

3. The method of claim 1, wherein contacting the hydrocarbon stream with the solvent composition comprises contacting the hydrocarbon stream in a liquid phase with the solvent composition in a liquid phase, with oxygen-containing compounds transferred from the hydrocarbon stream to the solvent composition.

4. The method of claim 3, further comprising separating an oxygenate-rich solvent composition in the liquid phase from the upgraded hydrocarbon stream in the liquid phase after contacting the hydrocarbon stream with the solvent composition.

5. The method of claim 4, further comprising regenerating the oxygenate-rich solvent composition to produce an oxygen-containing compound stream and a oxygenate-lean solvent stream.

6. The method of claim 5, further comprising separating the oxygenate-lean solvent stream into a drag stream and a recycle stream, wherein the recycle stream is combined with fresh solvent composition and contacts the hydrocarbon stream to reduce the residual oxygen-containing compound content of the hydrocarbon stream.

7. The method of claim 1, wherein contacting the hydrocarbon stream with the solvent composition comprises contacting the hydrocarbon stream with the solvent composition comprising a basic solvent.

8. The method of claim 1, wherein contacting the hydrocarbon stream with the solvent composition comprises contacting the hydrocarbon stream with the solvent composition at a fraction of the solvent composition to the hydrocarbon stream of from about 2 to about 10% by volume, based on the total volume of the hydrocarbon stream.

9. The method of claim 1, wherein providing the hydrocarbon stream comprises pyrolyzing a biomass feed to produce a pyrolysis product stream.

10. The method of claim 9, wherein pyrolyzing the biomass feed comprises catalytically pyrolyzing the biomass feed.

11. The method of claim 10, wherein catalytically pyrolyzing the biomass feed produces an intermediate pyrolysis stream, and wherein the method further comprises fractionating the intermediate pyrolysis stream to produce the deoxygenated pyrolysis product.

12. The method of claim 9, wherein pyrolyzing the biomass feed comprises thermally pyrolyzing the biomass feed.

13. The method of claim 12, further comprising deoxygenating the pyrolysis product stream to produce the deoxygenated pyrolysis product.

14. The method of claim 1, wherein providing the hydrocarbon stream comprises co-processing a pyrolysis product stream and a petroleum-based source of hydrocarbons to produce the hydrocarbon stream.

15. A method of upgrading a hydrocarbon stream, the method comprising the steps of:

pyrolyzing a biomass feed to produce a pyrolysis product stream;

contacting the pyrolysis product stream or a derivative thereof with a solvent composition that has a greater affinity for oxygen-containing compounds over hydrocarbons; and

separating an oxygenate-rich solvent composition from an upgraded hydrocarbon stream after contacting the hydrocarbon stream with the solvent composition.

16. The method of claim 15, wherein contacting the pyrolysis product stream or the derivative thereof with the solvent composition comprises contacting the pyrolysis product stream or the derivative thereof in a liquid phase with the solvent composition in a liquid phase.

17. An apparatus for upgrading a hydrocarbon stream, the apparatus comprising:

a pyrolysis unit for pyrolyzing a biomass feed to produce a pyrolysis product stream;

optionally, a deoxygenating unit for receiving the pyrolysis product stream and for deoxygenating the pyrolysis product stream;

an extraction unit, downstream of the optional deoxygenating unit, for receiving the hydrocarbon stream comprising a deoxygenated pyrolysis product and for extracting residual oxygen-containing compounds from the hydrocarbon stream.

18. The apparatus of claim 17, wherein the pyrolysis unit is further defined as a catalytic pyrolysis unit, and wherein the apparatus is free from the deoxygenating unit.

19. The apparatus of claim 17, wherein the pyrolysis unit is further defined as a thermal pyrolysis unit, and wherein the deoxygenating unit is present in the apparatus.

20. The apparatus of claim 17, further comprising a co-processing unit in fluid communication with the extraction unit, upstream of the extraction unit.

21. The method of claim 15, wherein the pyrolysis product stream or the derivative thereof is contacted with the solvent composition in an extraction column, and wherein separating the oxygenate-rich solvent composition from the upgraded hydrocarbon stream comprises collecting the oxygenate-rich solvent composition in the extraction column and removing the oxygenate-rich solvent composition from a bottom of the extraction column, with the hydrocarbon stream exiting the extraction column at a top thereof.