Carbon capture of COKE combustion processes

Abstract

Systems using a regenerator; a purification loop connected to the regenerator, wherein carbon dioxide is outputted to the purification loop, and wherein the purification loop comprises: a catalytic filter; a sulfur oxide sorbent injector; an nitric oxide reducing agent injector. The sulfur oxide sorbent injector and the nitric oxide reducing agent injector are located upstream of the catalytic filter. An oxygen injector is located upstream of the regenerator; and a main air blower that maintains directional gas flow within the purification loop. Methods including supplying oxygen to a regenerator; combusting a hydrocarbon in the regenerator; recycling exhaust gas from the regenerator in a purification loop connected thereto; purifying the exhaust gas through injection of sulfur oxide sorbent and nitric oxide reducing agent; filtering the purified exhaust gas through a catalytic filter; and maintaining directional gas flow of the exhaust gas through the purification loop.

Description

CARBON CAPTURE OF COKE COMBUSTION PROCESSESFIELD OF INVENTION

[0001] This application relates to methods and systems for hydrocarbon conversion, and capture of carbon dioxide and contaminants of emitted gas therefrom.BACKGROUND

[0002] Hydrocarbon conversion processes including coking and catalytic cracking (e.g., fluid catalytic cracking (FCC)) processes allow conversion of heavy, high-boiling point petroleum-derived hydrocarbons into valuable materials such as liquid fuel, with other byproducts including solid coke.

[0003] Catalytic cracking is used to convert heavy, high-boiling hydrocarbons into more valuable, lower-boiling products such as gasoline and diesel fuel. FCC processes begin with a feedstock, typically a heavy crude oil or vacuum gas oil, that may be preheated and introduced into a reactor and mixed with fluidizable catalyst particles.

[0004] Coking systems are commonly used for converting vacuum tower bottoms and / or other heavy residual petroleum materials to petroleum coke and other products. A majority of residual material processed in a coker will typically be recovered as fuel gas, coker gasoline / naphtha, light cycle oil (also commonly referred to by various other names such as light coker gas oil), and heavy cycle oil (also commonly referred to by various other names such as heavy coker gas oil).

[0005] Effective catalytic cracking and coking are of particular importance as there is currently a trend in refining industry toward processing of heavier, lower cost crudes. This results in refineries having to contend with increased quantities of heavy materials in the refining process. This further increases the demands on the refinery’s heavy hydrocarbon conversion processes, particularly coke processing and catalytic cracking. Because the greater part of a barrel of residuum e.g., the high boiling point bottom products from atmospheric or vacuum distillation columns) can be converted to value-add products including light ends, gasoline, distillate, and gas oil, such systems have become even more important in today’s refining economics.

[0006] With the growing concern about global climate change and the impact of carbon dioxide emissions, emphasis has been placed on minimizing carbon dioxide emissions from petrochemical processing operations, including coking systems. Carbon capture and storage remains a promising technology for reducing carbon dioxide emissions. Carbon capture and storage technologiesinclude oxy-fuel (also known as oxy-fired) combustion and capture of carbon dioxide, as well as membrane absorption and capture of carbon dioxide.SUMMARY OF INVENTION

[0007] Some aspects of the present disclosure describe systems comprising: a regenerator, the regenerator being a combustion unit of a hydrocarbon conversion system; a purification loop fluidly connected to the regenerator, wherein an initial quantity of carbon dioxide is outputted to the purification loop from the regenerator, and wherein the purification loop comprises: a catalytic filter; a sulfur oxide sorbent injector; an nitric oxide reducing agent injector, wherein the sulfur oxide sorbent injector and the nitric oxide reducing agent injector are located directly upstream of and fluidly connected to the catalytic filter; a high purity oxygen injector, wherein the high purity oxygen injector is located upstream of the regenerator; and a main air blower, wherein the main air blower maintains directional gas flow within the purification loop.

[0008] Other aspects of the present disclosure describe methods comprising: supplying high purity oxygen to a regenerator; combusting a hydrocarbon in the regenerator, converting the heavy hydrocarbon; recycling exhaust gas from the regenerator in a purification loop fluidly connected thereto; purifying the exhaust gas through injection of sulfur oxide sorbent and nitric oxide reducing agent; filtering the exhaust gas with the injected sulfur oxide sorbent and the nitric oxide reducing agent through a catalytic filter; and maintaining directional gas flow of the exhaust gas through the purification loop.

[0009] These and other features and attributes of the disclosed methods and systems of the present disclosure and their advantageous applications and / or uses will be apparent from the detailed description which follows.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] To assist those of ordinary skill in the relevant art in making and using the subject matter hereof, reference is made to the appended drawings. The following figures are included to illustrate certain aspects of the disclosure, and should not be viewed as exclusive configurations. The subject matter disclosed is capable of considerable modifications, alterations, combinations, and equivalents in form and function, as will occur to those skilled in the art and having the benefit of this disclosure.

[0011] FIG. 1 is a flow diagram of a first system according to the present disclosure.

[0012] FIG. 2 is a flow diagram of a second system according to the present disclosure.DETAILED DESCRIPTION

[0013] This application relates to methods and systems for hydrocarbon conversion, and capture of carbon dioxide and contaminants of emitted gas therefrom.

[0014] The present disclosure includes methods and systems relating to hydrocarbon conversion (e.g., coking, catalytic cracking) and processing and carbon dioxide capture thereof. The present disclosure allows for hydrocarbon conversion with capture of carbon dioxide and other pollutants in an effective manner. In particular, the present disclosure allows for capture of a high percentage of carbon dioxide from hydrocarbon processing, thus significantly reducing greenhouse gas emissions. Simultaneously, the methods and systems of the present disclosure are configured to capture other pollutants including sulfur oxides and nitric oxides in a highly efficient and effective manner, leading to lower cost and lower emissions. Methods and systems of the present disclosure may allow for a hydrocarbon conversion process to capture greater than 80 wt% (or 10 wt% to 99.999 wt%, or 1 wt% to 99.999 wt%, or 10 wt% to 90 wt%, or 80 wt% to 99.999 wt%, or greater than 90 wt%, or 90 wt% to 99.999 wt%, or greater than 95 wt%, or 95 wt% to 99.999 wt%, or greater than 98 wt%, or 98 wt% to 99.999 wt%, or greater than 99 wt%, or 99 wt% to 99.999 wt%) of carbon dioxide produced during combustion of the heavy hydrocarbon. Furthermore, the present disclosure offers improved system efficiency when integrated in current hydrocarbon processing operations, because the methods and systems described herein eliminate the need for wet waste handling, thereby eliminating additional costs and complexity associated with said wet waste processing. Systems of the present disclosure may also offer additional efficiencies including reduced energy use and lower unit and / or size footprint, as compared to conventional coke processing systems.

[0015] The present disclose may be applicable to hydrocarbon conversion processes (e.g., heavy hydrocarbon conversion processes, light hydrocarbon conversion processes, the like, or any combination thereof) including, but not limited to, for example, fluid catalytic cracking, fluid coking, methanol to gasoline (MTG), propane dehydrogenation, the like, or any combination thereof.

[0016] A system of the present disclosure may include a regenerator and a purification loop fluidly connected thereto. The purification loop may include therein a catalytic filter, one or more sulfur oxide sorbent injectors and a nitric oxide reducing agent, as well as a oxygen injector and a main air blower, wherein the main air blower maintains directional gas flow within the purification loop. It should be noted that “gas flow,” and grammatical variations thereof as used herein refer to the flow of fluid through the purification loop, including any solid, liquid, and / or gaseous material dispersed within the fluid (including particulate matter).

[0017] Various embodiments of the present disclosure will be described in detail with reference to the accompanying Figures. Further, in the following detailed description of embodiments of the present disclosure, numerous specific details are set forth in order to provide a more thorough understanding of the claimed subject matter. However, it will be apparent to one of ordinary skill in the art that the embodiments disclosed herein may be practiced without these specific details. In other instances, well- known features have not been described in detail to avoid unnecessarily complicating the description. Additionally, it will be apparent to one of ordinary skill in the art that the scale of the elements presented in the accompanying Figures may vary without departing from the scope of the present disclosure.

[0018] FIG. 1 shows an embodiment of the present disclosure including system 100. System 100 includes regenerator 110 with purification loop 102 fluidly connected thereto (note purification loop 102 is shown with dashed lines and includes components, lines, and the like fluidly connected thereto). Oxygen, preferably high purity oxygen, may be injected through oxygen injector 104 to the purification loop 102, thus supplying oxygen to the regenerator 110. Regenerator 110 may additionally have a sulfur oxide sorbent injected directly thereto through a, fluidly connected, first (optional) sulfur oxide (SOx) sorbent injector 106. Purification loop 102 may have directional gas flow as indicated by arrows 102a. “Upstream” and “downstream” as used herein refer to directions relating to the directional gas flow, such that the directional gas flow is oriented to flow from the upstream direction to the downstream direction. The purification loop 102 may optionally include a heat exchanger (HX) 115 directly downstream of the regenerator 110 for regulation of temperature of gas exiting the regenerator 110 before further processing. The purification loop 102 may include a catalytic filter 120, with second sulfur oxide sorbent (SOx) injector 122a and nitric oxide (NOx) reducing agent injector 122b located directly upstream of the catalytic filter 120, thus supplying sulfur oxide sorbent and nitric oxide reducing agent, respectively, to gas entering catalytic filter 120 within purification loop 102. It should be noted that in some embodiments second sulfur oxide sorbent (SOx) injector 122a and nitric oxide (NOx) reducing agent injector 122b may both be located downstream from HX 115. In some embodiments second sulfur oxide sorbent (SOx) injector 122a may be located upstream from HX 115 while nitric oxide (NOx) reducing agent injector 122b may be located downstream from HX 115. Furthermore, purification loop 102 may have a purge line 140 comprising a purge stream for use in maintenance operations (e.g., startup, adjustment, the like). The purge stream may purge a portion or all of the directional gas flow during such maintenance operations. Additionally, purification loop 102 may have a maintenance blower 144 fluidly connected thereto for use in engaging directional gas flow duringmaintenance operations. It should be noted that in some embodiments maintenance blower 144 may comprise a compressor. Purification loop 102 may maintain directional gas flow through use of a main air blower 130 comprising an induced draft (ID) fan. Purification loop 102 may further include thereon an exit line 150 for recovery of carbon dioxide product; exit line 150 may have thereon a final impurity control device 152 and an exit blower 154 for maintaining directional gas flow through exit line 150.

[0019] FIG. 2 shows an embodiment of the present disclosure including system 101. System 101 is described with continued reference to common elements in system 100. System 101 includes purification loop 103. System 101 includes regenerator 110 with purification loop 103 fluidly connected thereto (note purification loop 103 is shown with dashed lines and includes components, lines, and the like fluidly connected thereto). Regenerator 110 may additionally have a sulfur oxide sorbent injected directly thereto through a, fluidly connected, first (optional) sulfur oxide (SOx) sorbent injector 106. The purification loop 103 may optionally include a heat exchanger (HX) 115 directly downstream of the regenerator 110 for regulation of temperature of gas exiting the regenerator 110 before further processing. Oxygen may be injected through oxygen injector 104 to the purification loop 103. Purification loop 103 may have directional gas flow as indicated by arrows 103a. Purification loop 103 may further include a selective catalyst reduction unit 160 fluidly connected to and downstream of the regenerator 110. Purification loop 103 may further include a wet gas scrubber 170 with fluidly connected regenerative loop 172 including cooling and moisture control, as well as an attached wet gas scrubber flue conduit 174 for conveying a portion of the purification loop 103 directly downstream of wet gas scrubber 172. A two-way purge seal 176 may be fluidly connected to wet gas scrubber flue conduit 174 directly downstream of wet gas scrubber 170. Wet gas scrubber flue conduit 174 may be fluidly connected to a heat exchanger 180, the heat exchanger (HX) 180 fluidly connected to a supplementary filter 182, and the supplementary filter 182 fluidly connected to main air blower 184. Purification loop 103 may maintain directional gas flow through use of main air blower 184. Purification loop 103 may further include thereon an exit line 151; exit line 151 may have thereon a final impurity control device 152 and an exit blower 154 for maintaining directional gas flow through exit line 151 for recovery of carbon dioxide product. Exit line 151 may furthermore have a catalytic filter 120 located upstream of the final impurity control device 152, with second sulfur oxide (SOx) sorbent injector 122a and nitric oxide (NOx) reducing agent injector 122b located directly upstream of the catalytic filter 120, thus supplying sulfur oxide sorbent and nitric oxide reducing agent, respectively, to gas entering catalytic filter 120.

[0020] The regenerator may include any suitable combustion regeneration unit and may be implemented as part of any suitable system where carbon dioxide capture from oxy-fired combustion can be applied, including any suitable hydrocarbon conversion system. Gas exiting the regenerator may have any suitable temperature, including a temperature of 1000°F to 1500°F (538°C to 816°C), or about MOOT (760°C). If included, optional heat exchanger 115 may modify a temperature of gas exiting the regenerator to 500T to 800T (260°C to 428°C), or 500°F to 700°F (260°C to 371 °C), or 750°F (399°C) or less, or about 700°F (371°C).

[0021] As a first nonlimiting example, the regenerator may comprise a burner of a fluid coking system. In fluid coking systems the burner heats hot coke from a fluid coker reactor, and the burner produces a coke product. In the burner, combustion of the coked particles takes place to generate heat required for endothermic cracking reactions taking place in a reactor. The burner may be fluidly connected to an air blower which may blow air (e.g., heated air) to the burner to support combustion of materials within the burner. The portion of stripped coke (i.e., stripped of hydrocarbons) that is not burned in order to satisfy the heat requirements of the reactor may be recycled from the burner to a coking zone of the reactor to supply heat to support the endothermic cracking reactions. Further description of the function of such a burner and fluidly connected reactor may be found U.S. Pat. App. Pub. No. 2011 / 0206563 and U.S. Pat. Nos. 9,670,417 and 5,176,819 (all of which are incorporated herein by reference). One of ordinary skill in the art will be able to implement, within an fluid coking system, methods and systems of the present disclosure with the benefit thereof.

[0022] As a second nonlimiting example, the regenerator may comprise a regenerator of a fluid catalytic cracking (FCC) system. In such an FCC system, a hydrocarbon feed may be introduced to a reactor where the hydrocarbon feed may be converted or “cracked” with the aid of catalyst particulates. The spent catalyst particulates may then be passed to the regenerator. Within the regenerator, combustion may occur to process residual hydrocarbon remaining with the catalyst particulates, and flue gas from said combustion may thus be processed within a purification loop of the present disclosure. One of ordinary skill in the art will be able to implement, within an FCC system, methods and systems of the present disclosure with the benefit thereof.

[0023] There may be further suitable systems in which methods and systems of the present disclosure for carbon dioxide capture from oxy-fired combustion can be applied. As a further nonlimiting example, the coke combustion regenerator may comprise a converter of a propane dehydrogenation system (e.g., K-PRO™, available from KBR). Additionally as a nonlimiting example, the coke combustionregenerator may comprise a regenerator of a methanol to gasoline fluidized bed system. U.S. Patent No. 9,938,205, the disclose of which is incorporated by reference herein, describes an example methanol to gasoline process.

[0024] The purification loop may have an initial quantity of carbon dioxide outputted from the regenerator. The purification loop of systems of the present disclosure may be a complete or partial loop with units and conduits fluidly connecting such units therein. Units within the purification loop may have individual recycle loops, branches, and other variations that may connect to other parts of the purification loop and / or other units outside the purification loop.

[0025] The purification loop may have one or more exit lines wherein each exit line removes carbon dioxide from the purification loop. An exit line may include a final impurity control device. Such final impurity control device may comprise a filter, a separator {e.g., a cyclonic separator, the like), a scrubber, the like, or any combination thereof. Such final impurity control device may include a final moisture control unit and / or may include a residual agent control unit. A final moisture control unit may be included to allow for control of moisture of gas within the exit line prior to leaving the exit line. Any suitable moisture control means may be used in accordance with the present disclosure including, but not limited to, molecular sieving, the like, or any combination thereof. A residual agent control unit may be included to allow for control of any residual agents {e.g., residual reducing agent e.g., ammonia), residual sorbent, the like, or any combination thereof) of gas within the exit line prior to leaving the exit line. Such a residual agent control unit may utilize any suitable means of controlling the residual agents including, but not limited to, for example, catalytic conversion, sieving, the like, or any combination thereof.

[0026] Gas leaving the exit line following appropriate controls and purification (as previously described) may comprise carbon dioxide product. The carbon dioxide product may have a final quantity of carbon dioxide gas. Such carbon dioxide product may have a final quantity of carbon dioxide gas (or purity) on a dry basis (excluding water vapor) of 50 mol% to 100 mol% (or 75 mol% to 100 mol%, or 80 mol% to 100 mol%, or 90 mol% to 100 mol%, or 95 mol% to 100 mol%, or 99 mol% to 100 mol%, or 99.5 mol% to 100 mol%). The carbon dioxide product may have any suitable temperature include a temperature of 55°F to 140°F (13°C to 60°C) (or 70°F to 140°F (21°C to 60°C), or 55°F to 90°F (12°C to 32°C)).

[0027] The oxygen injector may supply high purity oxygen gas. High purity oxygen gas may comprise from 50 mol% to 100 mol% (or 75 mol% to 100 mol%, or 80 mol% to 100 mol%, or 90 mol% to 100mol%, or 95 mol% to 100 mol%, or 99 mol% to 100 mol%, or 99.5 mol% to 100 mol%) oxygen. The balance composition of the high purity oxygen gas may include various gasses commonly found within air including, but not limited to, nitrogen, argon, helium, water vapor, the like, or any combination thereof.

[0028] The nitric oxide reducing agent injector may inject a nitric oxide reducing agent (e.g., ammonia (e.g., ammonia hydroxide solution) into the gas flow of the purification loop, upstream of the catalytic filter. The nitric oxide reducing agent injector may have any suitable flow rate of nitric oxide reducing agent. The nitric oxide reducing agent may bind with the nitric oxide to form nitric oxide reduction byproducts. Such nitric oxide reduction byproducts may subsequently at least partially filtered through a catalytic filter of the present disclosure. The nitric oxide reducing agent may allow for removal of nitric oxides to a sufficient level at or below the specification of the carbon dioxide product. The nitric oxide reducing agent injector may enable the system to remove 30 mol% to 100 mol% (or 54 mol% to 100 mol%, or 50 mol% to 100 mol%, or 75 mol% to 100 mol%, or 80 mol% to 100 mol%, or 90 mol% to 100 mol%, or 95 mol% to 100 mol%, or 99 mol% to 100 mol%, or 99.5 mol% to 100 mol%) of nitric oxide produced from the coke combustion regenerator (as measured in the carbon dioxide product).

[0029] The first and / or second sulfur oxide sorbent injectors may each inject a sulfur oxide sorbent into the gas flow of the purification loop. Sulfur oxide sorbents of use in the present disclosure may generally comprise any suitable sorbent that is alkaline and / or is a Lewis base. Examples of suitable sulfur oxide sorbents may include, but are not limited to, e.g., ammonia, calcium oxide (e.g., burnt lime, hydrated lime, the like, or any combination thereof), the like, or any combination thereof. The first sulfur oxide sorbent injector may be directly and fluidly connected to the regenerator. The second sulfur oxide sorbent injector may be located directly upstream of the catalytic filter. Each sulfur oxide sorbent injector may have any suitable flow rate of sulfur oxide sorbent. The sulfur oxide sorbent may adhere or otherwise attach to a wall of the catalytic filter and be at least partially removed with upon pulse jet blow back action. As a result, the anti-sulfur oxide operations may hence produce only dry waste (in contrast with wet waste produced from conventional anti-sulfur oxide operations (e.g., a conventional wet gas scrubber)). The sulfur oxide sorbent may allow for removal of sulfur oxides to a sufficient level at or below the specification of the carbon dioxide product. The sulfur oxide sorbent injector may enable the system to remove 30 mol% to 100 mol% (or 40 mol% to 100 mol%, or 50 mol% to 100 mol%, or 75 mol% to 100 mol%, or 80 mol% to 100 mol%, or 90 mol% to 100 mol%, or 95 mol% to 100 mol%, or 99 mol% to 100 mol%, or 99.5 mol% to 100 mol%, or 40 mol% to 90 mol%, or 40 mol% to 99.9mol%) of sulfur oxide produced from the coke combustion regenerator (as measured in the carbon dioxide product).

[0030] As noted above, it should be noted that in some embodiments the second sulfur oxide sorbent injector and the nitric oxide reducing agent injector may both be located downstream from a heat exchanger, the heat exchanger being located directly downstream of the regenerator. In some embodiments the second sulfur oxide sorbent injector may be located directly downstream of the regenerator and upstream from a heat exchanger, while the nitric oxide reducing agent injector may be located downstream from the heat exchanger. Such a configuration wherein sulfur oxide sorbent may be injected upstream of a heat exchanger may allow for introduction of the sulfur oxide sorbent into gas exiting the regenerator at elevated temperature (e.g., about 1400F, and the like, as detailed above), thus allowing increased residence time for reaction of sulfur oxide sorbent and gas within the purification loop (prior to passage into the catalytic filter) and allowing reaction of sulfur oxide sorbent with sulfur oxides within gas in the purification loop at elevated temperature. Additionally, in such embodiments the nitric oxide reducing agent injector may be located directly upstream of the catalytic filter but downstream of the heat exchanger, as nitric oxide reduction may occur upon contact with the gas stream, necessitating a lower gas temperature and lower residence time (prior to passage into the catalytic filter).

[0031] The selective catalyst reduction (SCR) unit may comprise any suitable unit capable of selective catalyst reduction. The SCR may allow for adsorption, or otherwise reduction of nitric oxide (NOx) within the gas flow of the purification. The SCR may utilize suitable NOx reduction catalysts including, but not limited to, for example, a metal oxide catalyst, a precious metal catalyst, the like, or any combination thereof. One of ordinary skill in the art will be able to select and implement an appropriate SCR unit. It should further be noted that NOx may be reduced by adsorption and / or an additional reduction or other such purification system in combination with the SCR described herein, according to the present disclosure.

[0032] The wet gas scrubber may comprise any suitable scrubber for removing impurities from the gas flow of the purification loop. The scrubber may utilize concurrent, countercurrent, or both concurrent and countercurrent contact of gas and liquid as a means of removal of impurities from the gas flow. The wet gas scrubber may preferably comprise a cyclone-type scrubber {e.g., a Venturi scrubber). One of ordinary skill in the art will be able to select and implement an appropriate wet gas scrubber with the benefit of the present disclosure. Within the wet gas scrubber, a sorbent may be used. Such sorbent may comprise a basic (pH) material including, but not limited to, for example, an alkalimetal hydroxide, ammonia or ammonium hydroxide, the like, or any combination thereof. The wet gas scrubber within the present disclosure may operate at any suitable temperature, but generally should operate at a temperature at least 10°F about the ambient temperature where the scrubber is operating, including a temperature from 0°F to 200°F (-17°C to 94°C) (or 70°F to 170°F (21°C to 77°C), or 100 to 170 (38°C to 77°C) or 70°F to 100°F (21°C to 38°C), or 120°F to 170°F (49°C to 77°C)). Such temperature may be lower than conventional wet gas scrubbers, allowing for moisture content within flue gas exiting the wet gas scrubber of, for example, 0.01 vol% to 35 vol% (or 0.001 vol% to 30 vol%, or 0.01 vol% to 20 vol%, or 0.01 vol% to 10 vol%, or less than 35 vol%, or less than 10 vol%). Such moisture content may comprise a reduced moisture content in flue gas exiting the wet gas scrubber, as compared with conventional wet gas scrubbers. Lower moisture content may allow for a lower volumetric flowrate of gas flow within the wet gas scrubber, leading to a higher residence time and overall higher efficiency of impurity removal from the gas flow using the wet gas scrubber.

[0033] The wet gas scrubber may have a regenerative loop that may include features for providing additional cooling (e. ., through use of a chiller) and moisture control capacities to the wet gas scrubber. Such a regenerative loop may include one or more heat exchangers fluidly coupled to the wet gas scrubber.

[0034] Flue gas from the wet gas scrubber may be directed to a wet gas scrubber flue conduit. The wet gas scrubber flue conduit may comprise fiberglass reinforced plastic or any suitable material. Fiberglass reinforced plastic may allow increased resistance to degradation at a reduced cost as compared with conventional materials for wet gas scrubber flue conduits.

[0035] It should be noted that in some embodiments the wet gas scrubber may not be needed. As a result the system may have reduced need for wet waste handling and reduced need for water supply, reducing cost and complexity.

[0036] Wet gas scrubber flue gas may be heated prior to being compressed downstream of the wet gas scrubber. Such heating may allow operation of a compressor handling flue gas to operate above the flue gas dew point, reducing risk of corrosion, fouling, and the like. Generally, the operating temperature should be 10°F above the dew point or wet gas exist temperature. Said flue gas may be heated to a temperature of from 50°F to 300°F (10°C to 149°C) (or 150°F to 250°F (66°C to 121°C), or 150°F to 200°F (66°C to 93°C), or 200°F to 250°F (93°C to 121°C)). Furthermore, heating to such temperature may enable use of a conventional main air blower (see main air blower 184 of FIG. 2) as a compressor,due to a reduced risk of corrosion, fouling, and the like, potentially reducing or eliminating the need for modifications and / or maintenance to the main air blower.

[0037] The main air blower may serve to maintain the directional gas flow within the purification loop. The main air blower may comprise any suitable compressor or fan. One of ordinary skill in the art will be able to select the appropriate main airblower with the benefit of the present disclosure. The main air blower may comprise an induced draft (ID) fan (see FIG. 1) as in some embodiments the pressure drop across the catalytic filter and thus pressure drop within the purification loop may be sufficiently low so as to not require a compressor with greater than 4 stages. The ID fan may have a low number of stages due to the lower pressure and flow requirements of purification loops in some embodiments of the present disclosure. The ID fan may have 1 stage to 4 stages, or 1 stage to 3 stages, or 1 stage, or 2 stages, or 3 stages, or 4 stages.

[0038] It should further be noted that the main air blower may have additional features to increase lifespan and reduce maintenance due to effects including corrosion, erosion, fouling, the like, or any combination thereof. It should be noted that methods of implementing the herein described additional features of the main air blower may have added effects of reducing maintenance and / or optimizing operations of units and / or conduits other than the main air blower.

[0039] As a nonlimiting example, the main air blower may be engineered to reduce corrosion. As the gas flow within the purification loop may include trace amounts of sulfur oxides, nitric oxides, and water, an acidic environment may be present within the purification loop, potentially resulting in corrosion of main air blower components. The main air blower may have internal components that contact gas flow made wholly or partially of high-alloy steels, in contrast with a main air blower of a conventional system having internal components of low-grade (e.g., 400 series, 300 series) stainless steel and / or carbon steel.

[0040] As a nonlimiting example, the main air blower may be engineered to reduce erosion. Erosion may be of concern in systems with particulate matter in the gas flow in the purification loop. Particulate matter may increase risk of erosion of components within the main air blower, potentially increasing likelihood of deteriorated performance due to material removal on surfaces in contact with gas flow. Techniques including material coatings and material composition may be implemented to reduce corrosion in the main air blower, in addition to mitigation of erosion due to appropriate removal of particulates by filters (including the catalytic filter) as previously described herein. Material coatings of interest may include claddings including, but not limited to, for example, CONFORM ACL AD™ andULTRAFLEX™ (both available form Kennametal). Other material coatings of interest may include thermal spray coatings (e.g., chromium carbide coatings, tungsten carbide coatings, the like, or any combination thereof) including, but not limited to, for example, SUPER D-GUN™ (available from Linde).

[0041] As a nonlimiting example, the main air blower may be engineered to reduce fouling. Fouling may be of concern in systems with depositable particulate matter in gas flow. Fouling may lead to buildup on main air blower components, potentially leading to impacts including, but not limited to, for example, degradation, corrosion, mechanical wear, mechanical sticking, the like, or any combination thereof. Methods of reducing fouling in main air blowers may include anti-foulant coatings including, but not limited to, for example, POS-E-COAT™ (available from Elliot Turbo), HICOAT™ (available from Sulzer), SERMALON™ (available from Praxair), the like, or any combination thereof. Furthermore, methods of reducing fouling in main airblowers may include installation of inlet fdtration systems to reduce depositable particulate matter entering the main air blower. Such inlet fdtration systems may include, but are not limited to, for example, a bag fdter, a cartridge fdter, a ceramic fdter, the like, or any combination thereof.

[0042] The catalytic fdter may comprise any suitable fdter for removal of particulate matter from the gas flow of the purification loop. Said fdter may be capable of substantially removing fine particulate matter including particles with average dimension (e.g., diameter) smaller than 10 microns, or preferably particles with average dimension smaller than 1 microns. The highly efficient removal of particulate matter from the gas flow may allow for reduced corrosive potential of units within the purification loop including, but not limited to, for example, the main air blower. The catalytic fdter may furthermore have catalytic properties for processing of gas flow within the purification loop, including catalyst(s) for removing nitric oxides, sulfur oxides, other particulate matter, or any combination thereof. As a nonlimiting example, catalytic filters of the present disclosure may process sulfur oxides through surface binding to catalytic materials within the catalytic fdter. As a further nonlimiting example, catalytic filters of the present disclosure may process nitric oxide reduction byproducts upon passage through the catalytic fdter.

[0043] Said catalytic filters may be able to withstand process temperatures, including temperatures above 400°F (204°C) (or above 500°F (260°C), or above 600°F (316°C), or above 700°F (371 °C), or above 800°F (427°C), or from 400°F to 800°F (204°C to 427°C), or 400°F to 1000°F (204°C to 538°C), or 700°F to 1500°F (371°C to 816°C)). Of note is the fact that catalytic service, such as to remove NOxis generally run at temperatures at 1200°F and below whereas service at 1500°F is generally non- catalytic, removing only particles and SOx. Such process temperatures may be higher than conventional systems. Said elevated process temperatures may reduce potential for corrosion (e.g., dew point corrosion) in units (e.g., the main air blower) and conduits of the purification loop during operation. Catalytic filters used in the present disclosure may include a ceramic fiber material comprising, for example, including, but not limited to, alumino-silicate fibers. Catalytic filters used in the present disclosure may also include other materials, including, but not limited to, zeolite-based porous materials, silica-based porous materials, sintered metals, the like, or any combination thereof. Catalytic filters of the present disclosure may include nitric oxide (NOx) reduction catalysts. Any suitable nitric oxide reduction catalysts may be used in accordance with the present disclosure including, but not limited to, for example, a metal oxide catalyst, a precious metal catalyst. Examples of suitable nitric oxide reduction catalysts may include, but are not limited to, vanadium oxides, titanium dioxide, the like, or any combination thereof. Such nitric oxide reduction catalysts, if included, may work in combination with previously introduced nitric oxide reducing agent (e.g., ammonia, as described above) to reduce nitric oxide within the catalytic filter by filtration of nitric oxide reduction byproducts, as described above. Suitable commercial examples of catalytic filters may include, but are not limited to, for example, CERAFIL™ (available from Clear Edge) or TOPFRAX™ (available from Topsoe).

[0044] The present disclosure may further include methods of operating the system described above. Said methods may include supplying the oxygen to the coke combustion regenerator and using the oxygen to combust coke product in the coke combustion regenerator. The method may further include recycling exhaust gas from the coke combustion regenerator through the purification loop fluidly connected thereto. Within the purification loop, purification may include injection, into the exhaust gas, sulfur oxide sorbent, nitric oxide reducing agent, or any combination thereof. The previously injected exhaust gas may subsequently be filtered through a catalytic filter. Within the purification loop, the exhaust gas may be maintained in a directional gas flow through use of the previously described main air blower. It should be noted that methods of the present disclosure may further include starting the regenerator, wherein the starting process includes purging at least a portion of the directional gas flow of exhaust gas through the purge stream with initial introduction of air using the maintenance blower. Subsequently, the method may include gradually increasing, from zero flow, the supply of oxygen to the purification loop, while simultaneously decreasing the flow of the air (from the maintenance blower) and the flow through the purge stream until the air supply and the purge stream are substantially notflowing (or are not flowing at all) and oxygen is supplying oxygen to the regenerator, enabling oxy-fired operation of the system.

[0045] It should be noted that additional nonlimiting components may be present in systems of the present disclosure. Such additional components will be familiar to one having ordinary skill in the art and include, but are not limited to, valves, heat exchangers, conduits, gauges, sensors, compressors, controllers, the like, or any combination thereof.

[0046] To facilitate a better understanding of the embodiments of the present invention, the following examples of preferred or representative embodiments are given. In no way should the following examples be read to limit, or to define, the scope of the invention.Additional Embodiments

[0047] Embodiment A: A system comprising: a regenerator, the regenerator being a combustion unit of a hydrocarbon conversion system; a purification loop fluidly connected to the regenerator, wherein an initial quantity of carbon dioxide is outputted to the purification loop from the regenerator, and wherein the purification loop comprises: a catalytic filter; a sulfur oxide sorbent injector; an nitric oxide reducing agent injector, wherein the sulfur oxide sorbent injector and the nitric oxide reducing agent injector are located directly upstream of and fluidly connected to the catalytic filter; a high purity oxygen injector, wherein the high purity oxygen injector is located upstream of the regenerator; and a main air blower, wherein the main air blower maintains directional gas flow within the purification loop.

[0048] Embodiment A may have one or more of the following Elements in any combination:

[0049] Element A2: wherein the purification loop further comprises: a purge stream, wherein the purge stream is configured to purge the directional gas flow during maintenance operations of the regenerator; and wherein the main air blower comprises an induced draft (ID) fan, wherein the ID fan.

[0050] Element A3: further comprising: an exit line of the purification loop, wherein the exit line includes a final impurity control before release of a carbon dioxide product.

[0051] Element A4: wherein the carbon dioxide product has a purity of 90 mol% to 100 mol% on a dry basis (excluding water vapor).

[0052] Element A5: wherein the ID fan has from 1 to 4 compression stages.

[0053] Element A6: further comprising: a selective catalyst reduction unit; a wet gas scrubber fluidly connected to the selective catalyst reduction unit, the wet gas scrubber coupled to a regenerative loop including a chiller and moisture control device, and wherein at least a portion of the wet gas scrubber flue gas is directed through a wet gas scrubber flue gas conduit; and the sulfur oxide sorbent injector,the nitric oxide reducing agent injector, and the catalytic fdter are located on an exit line of the purification loop, wherein the exit line includes a final impurity control before release of a carbon dioxide product.

[0054] Element A7: wherein the wet gas scrubber has a temperature from 10°F above the ambient temperature where the scrubber is operating to 170°F.

[0055] Element A8: wherein the wet gas scrubber flue gas directed through the wet gas scrubber flue gas conduit has a temperature from 10°F above the ambient temperature where the scrubber is operating 10F above the wet gas exist temperature to 170°F.

[0056] Element A9: wherein the carbon dioxide product has a purity of 90 mol% to 100 mol% on a dry basis (excluding water vapor).

[0057] Element A10: further comprising: a supplementary filter fluidly connected to and downstream of the wet gas scrubber flue gas line.

[0058] Element Al l : further comprising an air compressor downstream of and fluidly connected to the supplementary filter, wherein the wet gas scrubber flue gas has a temperature of 70°F to 170°F immediately prior to entering the air compressor.

[0059] Element A12: wherein the high purity oxygen injector injects greater than 95 mol% oxygen.

[0060] Element Al 3: wherein the catalytic filter contains therein a nitric oxide reduction catalyst.

[0061] Element 14: wherein (a) the sulfur oxide sorbent injector enables the system to remove 40 mol% to 99 mol% of sulfur oxide from the regenerator, (b) the nitric oxide reducing agent enables the system to remove 40 mol% to 99 mol% of nitric oxide from the regenerator, or (c) the sulfur oxide sorbent injector enables the system to remove 40 mol% to 99 mol% of sulfur oxide from the regenerator and the nitric oxide reducing agent enables the system to remove 40 mol% to 99 mol% of nitric oxide from the regenerator.

[0062] Element Al 5: wherein the system captures greater than 95 wt% of carbon dioxide from the regenerator.

[0063] Element Al 6: wherein the hydrocarbon conversion system comprises a fluid catalytic cracking system or a fluid coking system.

[0064] By way of non-limiting example, come combinations applicable to A include: Embodiment A with Elements A3 and A4; A with Elements A2 and A5; A with Elements A6 and A7; A with Elements A6, A7, and A8; A with Elements A6, A10, and Al 1; A with Elements A6 and A13.

[0065] Embodiment B: A method comprising: supplying high purity oxygen to a regenerator; combusting a hydrocarbon in the regenerator in the presence of the high purity oxygen; recycling exhaust gas from the regenerator in a purification loop fluidly connected thereto; purifying the exhaust gas through injection of sulfur oxide sorbent and nitric oxide reducing agent; filtering the exhaust gas with the injected sulfur oxide sorbent and the nitric oxide reducing agent through a catalytic filter; and maintaining directional gas flow of the exhaust gas through the purification loop.

[0066] Embodiment B may have one or more of the following Elements in any combination:

[0067] Element Bl : wherein the carbon dioxide product has a temperature from 55°F to 140°F.

[0068] Element B2: further comprising: starting the regenerator, wherein starting comprises: supplying a quantity air to the regenerator from a maintenance blower; purging at least a portion of the exhaust gas through a purge stream; and increasing, from zero, the supply of high purity oxygen to the purification loop

[0069] Element B3: wherein converting the hydrocarbon comprises fluid catalytic cracking or fluid coking.

[0070] By way of non-limiting example, come combinations applicable to B include: Embodiment B with Elements Bl and B2; B with Elements Bl and B3; B with Elements Bl, B2, and B3.

[0071] Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, reaction conditions, and so forth used in the present specification and associated claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the incarnations of the present inventions. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claim, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0072] One or more illustrative incarnations incorporating one or more invention elements are presented herein. Not all features of a physical implementation are described or shown in this application for the sake of clarity. It is understood that in the development of a physical embodiment incorporating one or more elements of the present invention, numerous implementation-specific decisions must be made to achieve the developer's goals, such as compliance with system -related, business-related, government-related and other constraints, which vary by implementation and from time to time. Whilea developer's efforts might be time-consuming, such efforts would be, nevertheless, a routine undertaking for those of ordinary skill in the art and having benefit of this disclosure.

[0073] While compositions and methods are described herein in terms of “comprising” various components or steps, the compositions and methods can also “consist essentially of’ or “consist of’ the various components and steps.

[0074] Therefore, the present invention is well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular examples and configurations disclosed above are illustrative only, as the present invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular illustrative examples disclosed above may be altered, combined, or modified and all such variations are considered within the scope and spirit of the present invention. The invention illustratively disclosed herein suitably may be practiced in the absence of any element that is not specifically disclosed herein and / or any optional element disclosed herein. While compositions and methods are described in terms of “comprising,” “containing,” or “including” various components or steps, the compositions and methods can also “consist essentially of’ or “consist of’ the various components and steps. All numbers and ranges disclosed above may vary by some amount. Whenever a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within the range is specifically disclosed. In particular, every range of values (of the form, “from about a to about b,” or, equivalently, “from approximately a to b,” or, equivalently, “from approximately a-b”) disclosed herein is to be understood to set forth every number and range encompassed within the broader range of values. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. Moreover, the indefinite articles “a” or “an,” as used in the claims, are defined herein to mean one or more than one of the element that it introduces.

Claims

CLAIMSWhat is claimed is:

1. A system comprising: a regenerator, the regenerator being a combustion unit of a hydrocarbon conversion system; a purification loop fluidly connected to the regenerator, wherein an initial quantity of carbon dioxide is outputted to the purification loop from the regenerator, and wherein the purification loop comprises: a catalytic filter; a sulfur oxide sorbent injector; a nitric oxide reducing agent injector, wherein the sulfur oxide sorbent injector and the nitric oxide reducing agent injector are located directly upstream of and fluidly connected to the catalytic filter; a high purity oxygen injector, wherein the high purity oxygen injector is located upstream of the regenerator; and a main air blower, wherein the main air blower maintains directional gas flow within the purification loop.

2. The system of claim 1 wherein the purification loop further comprises: a purge stream, wherein the purge stream is configured to purge the directional gas flow during maintenance operations of the regenerator; an exit line of the purification loop, wherein the exit line includes a final impurity control before release of a carbon dioxide product; and, wherein the main air blower comprises an induced draft (ID) fan.

3. The system of claim 2, wherein the carbon dioxide product has a purity of 90 mol% to 100 mol% on a dry basis (excluding water vapor).

4. The system of claims 1-3, further comprising: a selective catalyst reduction unit; a wet gas scrubber fluidly connected to the selective catalyst reduction unit, the wet gas scrubber coupled to a regenerative loop including a chiller and moisture control device, and whereinat least a portion of the wet gas scrubber flue gas is directed through a wet gas scrubber flue gas conduit; and the sulfur oxide sorbent injector, the nitric oxide reducing agent injector, and the catalytic fdter are located on an exit line of the purification loop, wherein the exit line includes a final impurity control before release of a carbon dioxide product.

5. The system of claim 4, wherein the wet gas scrubber has a temperature from 10°F above the ambient temperature where the scrubber is operating to 170°F.

6. The system of claim 4, wherein the carbon dioxide product has a purity of 90 mol% to 100 mol% on a dry basis (excluding water vapor).

7. The system of claim 4, further comprising a supplementary filter fluidly connected to and downstream of the wet gas scrubber flue gas line.

8. The system of claim 7, further comprising an air compressor downstream of and fluidly connected to the supplementary filter, wherein the wet gas scrubber flue gas has a temperature of 70°F to 170°F immediately prior to entering the air compressor.

9. The system of claims 1-3, wherein the high purity oxygen injector injects greater than 95 mol% oxygen.

10. The system of claims 1-3, wherein the catalytic filter contains therein a nitric oxide reduction catalyst.

11. The system of claims 1-3, wherein(a) the sulfur oxide sorbent injector enables the system to remove 40 mol% to 99 mol% of sulfur oxide from the regenerator,(b) the nitric oxide reducing agent enables the system to remove 40 mol% to 99 mol% of nitric oxide from the regenerator, or(c) the sulfur oxide sorbent injector enables the system to remove 40 mol% to 99 mol% of sulfur oxide from the regenerator and the nitric oxide reducing agent enables the system to remove 40 mol% to 99 mol% of nitric oxide from the regenerator.

12. The system of claims 1-3, wherein the system captures greater than 95 wt% of carbon dioxide from the regenerator.

13. A method comprising: supplying high purity oxygen to a regenerator; combusting a hydrocarbon in the regenerator in the presence of the high purity oxygen; recycling exhaust gas from the regenerator in a purification loop fluidly connected thereto; purifying the exhaust gas through injection of sulfur oxide sorbent and nitric oxide reducing agent; filtering the exhaust gas with the injected sulfur oxide sorbent and the nitric oxide reducing agent through a catalytic filter; and maintaining directional gas flow of the exhaust gas through the purification loop.

14. The method of claim 13, further comprising: starting the regenerator, wherein starting comprises: supplying a quantity air to the regenerator from a maintenance blower; purging at least a portion of the exhaust gas through a purge stream; and increasing, from zero, the supply of high purity oxygen to the purification loop.

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