Fluidized bed lipid conversion

Abstract

A method includes: (a) processing a lipid feedstock in a fluidized bed reactor over a fluidized particulate catalyst in a gas-based stream to obtain a processed stream and a spent catalyst containing coke deposits; (b) continuously introducing the spent catalyst containing coke deposits into a catalyst regeneration unit; (c) continuously operating the catalyst regeneration unit to burn away coke deposits from the spent catalyst, thereby obtaining a regenerated particulate catalyst; and (d) continuously introducing the regenerated particulate catalyst from the catalyst regeneration unit into the fluidized bed reactor.

Description

[0001] Priority Claim

[0002] This application claims priority to U.S. Provisional Patent Application Serial No. 63 / 417,057, filed October 18, 2022, entitled "Fluid Bed Lipid Conversion", the contents of which are incorporated herein by reference in their entirety. Background Art

[0003] In the production of hydrocarbons suitable as fuels or fuel components (such as for transportation fuels or compatible with fuels), there is increasing interest in alternative feedstocks for at least partially replacing crude oil. Biofuels are typically made from feedstocks derived from renewable sources, which include oils obtained from plants, animals, algal matter, fish, as well as various waste streams, by-product streams, and sewage sludge. These feedstocks, especially various waste streams and by-product streams, contain varying amounts of contaminants such as gums, organochlorine compounds, phospholipids and other phosphorus compounds, metals and metal compounds, and residual soaps, which are harmful to, for example, conversion catalysts. Summary of the Invention

[0004] According to an example embodiment, a method includes:

[0005] (a) processing a lipid feedstock above a fluidized particulate catalyst in a gas-based feed stream in a fluidized bed reactor to obtain a processed feed stream and a spent catalyst containing coke deposits;

[0006] (b) continuously introducing the spent catalyst containing coke deposits into a catalyst regeneration unit;

[0007] (c) continuously operating the catalyst regeneration unit to burn off the coke deposits from the spent catalyst to obtain a regenerated particulate catalyst; and

[0008] (d) continuously introducing the regenerated particulate catalyst from the catalyst regeneration unit into the fluidized bed reactor. Description of the Drawings

[0009] The above and other objects, features, and advantages of the example embodiments of the present disclosure will become more apparent from the following detailed description in conjunction with the accompanying drawings.

[0010] Figure 1 A conventional reactor unit is shown.

[0011] Figure 2 A fluidized bed reactor unit and a catalyst regeneration unit according to an example embodiment are shown.

[0012] Figure 3Shows a fluidized bed reactor unit with a riser and a catalyst regeneration unit according to an exemplary embodiment.

[0013] Figure 4 Shows a fluidized bed reactor unit with a riser and a catalyst regeneration unit according to an exemplary embodiment. Detailed Description

[0014] The various exemplary embodiments described herein generally relate to processing renewable feedstocks for refining processes to produce chemicals, fuels, lubricants, or components thereof.

[0015] Definitions

[0016] The term "lipid" is known in the art and refers to fatty acids and their derivatives. Thus, examples of lipids include fatty acids (saturated and unsaturated fatty acids); glycerides or glycerolipids, also known as acylglycerols (such as monoglycerides (monoacylglycerols), diglycerides (diacylglycerols), triglycerides (triacylglycerols, TAGs, or neutral fats); phosphoglycerides (glycerophospholipids); non-glyceride lipids (sphingolipids, sterol lipids (including cholesterol and steroid hormones), prenol lipids (including terpenoids), fatty alcohols, waxes, and polyketides); and complex lipid derivatives (sugar-linked lipids or glycolipids, and protein-linked lipids).

[0017] The term "fatty acid" refers to a monocarboxylic acid having an aliphatic chain containing from about 3 to about 39 carbon atoms, more particularly from about 7 to about 23 carbon atoms. The aliphatic chain can be straight or branched and can be saturated or unsaturated (e.g., containing one or more carbon-carbon double bonds).

[0018] The term "bio-oil" refers to a liquid product produced from biomass by a thermochemical process. Bio-oil can include hydrocarbon fractions and oxygenated hydrocarbons of biological origin, such as carboxylic acids, alcohols, aldehydes, ketones, etc.

[0019] As used herein, the term "spent catalyst" refers to a catalyst that has a lower activity under the same or similar reaction conditions (e.g., temperature, pressure, inlet flow rate, etc.) than when it was initially exposed to the process. This can be caused by a variety of reasons, and several non-limiting examples of catalyst activity reduction include coking or adsorption or accumulation of carbonaceous materials, steam or hydrothermal deactivation, adsorption or accumulation of metals (and ash), attrition, morphological changes including pore size changes, cationic or anionic substitution, and / or chemical or compositional changes.

[0020] As used herein, the term "renewable feedstock" refers to materials derived from renewable resources (such as plants) and not of geological origin. The term "renewable" is also synonymous with the terms "sustainable", "sustainably derived", or "from sustainable sources". The term "geological origin" refers to materials derived from, for example, crude oil, natural gas, or coal. Materials of "geological origin" are not easily replenished or regenerated (e.g., in contrast to oils produced by plants or algae).

[0021] The term "hydrotreating" generally encompasses all processes in which a hydrocarbon feedstock is reacted with hydrogen in the presence of a catalyst and under hydrotreating conditions (typically at elevated temperature and elevated pressure). Hydrotreating includes processes such as hydrogenation, hydrodeoxygenation, hydrodesulfurization, hydrodenitrogenation, hydrodemetallization, hydrodearomatization, hydroisomerization, hydrocracking, mild hydrocracking, and the like.

[0022] As used herein, the term "transport fuel" refers to hydrocarbon fractions, cuts, or mixtures having a standardized distillation curve for a fuel, such as diesel (middle distillate from 160 °C to 380 °C according to EN 590), gasoline (40 °C to 210 °C according to EN228), aviation fuel (jet fuel according to ASTM D-1655, 160 °C to 300 °C), kerosene, naphtha, and the like. Liquid fuels are hydrocarbons having a standardized distillation curve for a fuel, such as transport fuels.

[0023] "ppm" as used herein refers to parts per million, which is a relative weight parameter. Parts per million is equal to grams / micrograms, so a component with a content of 10 ppm means that in every 1 gram of the total mixture, the content of that particular component is 10 micrograms.

[0024] The term "upgrading" refers to the process of changing a feedstock to have more desirable properties.

[0025] As used herein, the term "biofuel" refers to liquid fuels obtained from renewable feedstocks (such as bio-based feedstocks).

[0026] As described above, in the process of producing hydrocarbons suitable as fuels or fuel components (such as for use as transport fuels or being compatible with fuels), there is an increasing interest in alternative feedstocks for at least partially replacing crude oil. Biofuels are typically made from feedstocks of renewable origin. These feedstocks, especially various waste streams and by-product streams, contain varying amounts of contaminants such as gums, organochlorine compounds, phospholipids and other phosphorus compounds, metals and metal compounds, and residual soaps, which are harmful to, for example, conversion catalysts.

[0027] Currently, a process for treating low-carbon intensity lipid feedstocks to remove impurities and most of the oxygen, thereby producing a product mixture that can be processed in a hydrotreating unit of a conventional refinery without further treatment, uses conventional hydrotreating catalysts. This is shown in Figure 1 as follows, Figure 1 showing that the lipid feedstock is fed into a reactor and introduced in a spray form through a set of nozzles above the catalyst bed. The reaction takes place in the catalyst bed, and the reactor effluent containing the product is discharged from the bottom of the reactor. Steam can also be optionally introduced at the top of the reactor.

[0028] In the process using the Figure 1 reactor shown, the lipid feedstock reacts above a catalyst containing oxides in the catalyst bed. A small amount of coke is formed during this process, the coke accumulates on the catalyst, and the coke is removed by carbon burning in air or diluted air. Any non-volatile by-products dissolved in the lipid feedstock, such as metal oxides or metal carbonates (formed by the decomposition of the corresponding soaps in the feedstock), also accumulate on the catalyst surface or in the void spaces around the catalyst particles and are removed from the process stream. These metal impurities do not burn during the carbon burning process and can partially accumulate on the catalyst over time, and may also form dust that accumulates in the voids between the catalyst particles. Coke and these impurities cause reactor blockage. In addition, the reaction temperature can also cause excessive fouling on the heater surface.

[0029] There is a desire to have a process and system (such as a reactor) that can avoid the above problems. Accordingly, the non-limiting exemplary embodiments described herein overcome these and other disadvantages and provide an improved process for purifying renewable feedstocks that allows for catalyst regeneration by carbon burning while suppressing or preventing coke blockage in the reactor. In a non-limiting exemplary embodiment, a process includes:

[0030] (a) Processing a lipid feedstock above a fluidized particulate catalyst in a gas-based stream in a fluidized bed reactor to obtain a processed stream and spent catalyst containing coke deposits;

[0031] (b) Continuously introducing the spent catalyst containing coke deposits into a catalyst regeneration unit;

[0032] (c) Continuously operating the catalyst regeneration unit to burn off the coke deposits from the spent catalyst, thereby obtaining regenerated particulate catalyst; and

[0033] (d) Continuously introducing the regenerated particulate catalyst from the catalyst regeneration unit into the fluidized bed reactor.

[0034] Lipid feedstock

[0035] The lipid feedstocks used in the exemplary embodiments disclosed herein are derived from renewable or biological sources and are intended to include feedstocks other than those obtained from mineral oil, shale oil, or coal. In the exemplary embodiments, the lipid feedstocks are partially decomposed and / or hydrolyzed.

[0036] In the exemplary embodiments, the lipid feedstocks applicable herein may include, for example, from 0 to about 90 wt.% free fatty acids, from about 5 to 100 wt.% fatty acid glycerides (e.g., monoglycerides, diglycerides, triglycerides), and from 0 to about 20 wt.% of one or more compounds selected from non-glyceride fatty acid esters, fatty amides, and fatty alcohols. In the exemplary embodiments, in combination with the foregoing embodiments, the lipid feedstock comprises more than about 50 wt.% free fatty acids and fatty acid glycerides, such as about 70 wt.% or more, such as about 80 wt.% or more and up to 100 wt.%.

[0037] In the exemplary embodiments, the lipid feedstock may include lipids (e.g., fats or oils) derived from, for example, any type of plant, animal, microorganism (such as algae (e.g., algal oil, algal biomass, algal culture), fish, and microbial processes). In the embodiments, the lipid feedstock used includes triglycerides.

[0038] Many different lipid feedstocks derived from plants can be used. In non-limiting exemplary embodiments, plant-based lipid feedstocks may include, for example, rapeseed oil, soybean oil (including degummed soybean oil), canola oil, cottonseed oil, grapeseed oil, mustard oil, corn oil, linseed oil, safflower oil, sunflower oil, pecan oil, walnut oil, oat oil, peanut oil, rice bran oil, camellia oil, castor oil, and olive oil, palm oil, coconut oil, rice oil, algal oil, seaweed oil, and Chinese tallow tree oil. Other plant-based lipid feedstocks may be derived from, for example, argan, avocado, babassu palm, Balanites tree, Borneo tallow nut, Brazil nut, calendula, camelina, myrtle, cashew, Chinese tallow tree, cocoa, coffee, cohune palm, coriander, cucurbitaceae, euphorbia, illipe nut, jatropha, jojoba, kenaf, bitter kola tree, macadamia nut, mango seed, Ethiopian niger nut, nutmeg, perilla, Philippine fruit, pumpkin seed, rice bran, inca nut, seje palm, sesame, shea nut, tesed, albizia tree, almond, chaulmoogra tree, cuphea, jatropha, karanja tree seed, neem, papaya, tonka bean, tung tree, ucuuba tree, melaleuca, prickly ash, davana, galbanum, German chamomile, hexastylis, gaultheria american mint, phoenix, lupinus, lemon balm, yarrow, ningde, patchouli, tarragon, and mugwort.

[0039] Many different lipid feedstocks derived from animals can also be used. In non-limiting exemplary embodiments, animal-based lipid feedstocks can include, for example, selected white grease, lard (pig fat), tallow (beef fat), fish oil, and poultry fat.

[0040] Many different lipid feedstocks derived from microorganisms (eukaryotes, eubacteria, and archaea) can also be used. In non-limiting exemplary embodiments, microorganism-based lipid feedstocks can include, for example, L-glycerolipids of archaea, algae, and diatom oil. In some embodiments, microorganism-derived lipid feedstocks can include bacteria, protozoa, algae, and fungi.

[0041] In some embodiments, lipid feedstocks derived from both plant and animal sources can be used, such as yellow grease, white grease, and brown grease. In non-limiting exemplary embodiments, yellow, white, or brown grease can include frying oil from a fryer and thus can include fats from both plant and animal sources. The lipid feedstock can specifically include waste cooking oil. Brown grease (also known as grease trap grease) can include fats extracted from sewage systems and thus can include fats from both plant and animal sources. In some embodiments, the lipid feedstock used in the embodiments can include abiotic lipid feedstocks. The lipid feedstocks of the present disclosure can also include black oil.

[0042] In non-limiting exemplary embodiments, the lipid feedstock includes feedstocks derived from low-value renewable waste, by-product streams, by-products, refining waste and residues, sewage sludge, and any combination thereof.

[0043] In non-limiting exemplary embodiments, the lipid feedstock can be selected from acidulated soapstock, fatty acid distillates from physical refining of vegetable oil or animal fat, distilled corn oil (DCO) from the ethanol production process, waste cooking oil, lard, brown grease, yellow grease, grease trap grease, waste fat, low-grade oil, supercritical water liquefaction oil (SCWL oil), vegetable oil, animal fat, and any combination thereof.

[0044] In an exemplary embodiment, which may be combined with one or more of the foregoing paragraphs, the lipid feedstock contains one or more alkali metals, alkaline earth metals, and / or other metals, such as iron and manganese, which are often considered unsuitable for catalytic processing in refining operations, even in low amounts, because each metal is an effective catalyst poison. Alkali metals, alkaline earth metals, and other metals typically may include Na, K, Mg, Ca, Mn, Fe, or combinations thereof. In an exemplary embodiment, the lipid feedstock may contain a total of at least about 1 ppm (e.g., about 1 to about 250 ppm, about 1 to about 100 ppm, about 1 to about 50 ppm, about 1 to about 25 ppm, about 2 to about 250 ppm, about 2 to about 100 ppm, or about 2 to about 25 ppm) of alkali metals, alkaline earth metals, Group VIIB and Group VIIIB metals, or combinations thereof, calculated as elemental metal. The total metal content may be determined using the AOCS recommended method Ca 17-01.

[0045] In a non-limiting exemplary embodiment, the lipid feedstock may include low-value lipid feedstocks, such as various types of animal fats and waste oils, which typically have relatively high free fatty acid concentrations. One way to evaluate the free fatty acid concentration is to determine the total acid number (TAN) of the feedstock. The total acid number is the mass in milligrams of potassium hydroxide (KOH) required to neutralize 1 gram of the chemical being evaluated.

[0046] In an exemplary embodiment, which may be combined with one or more of the foregoing paragraphs, the total acid number of the lipid feedstock may be at least about 5 mg KOH / g (e.g., about 5 to about 150 mg KOH / g, about 10 to about 150 mg KOH / g, about 10 to about 100 mg KOH / g, about 10 to about 50 mg KOH / g, about 10 to about 25 mg KOH / g, or about 10 to about 20 mg KOH / g). The total acid number may be determined using ASTM D664.

[0047] Lipid feedstocks typically contain varying amounts of impurities, such as phosphorus, silicon, chlorides, alkali metals, alkaline earth metals, other metals, etc. In an exemplary embodiment, which may be combined with one or more of the foregoing paragraphs, the lipid feedstock may contain varying amounts of chlorides, such as at least about 2 ppm, or at least about 4 ppm, or at least about 10 ppm (e.g., about 2 to about 100 ppm, about 2 to about 75 ppm, about 2 to about 50 ppm, about 10 to about 100 ppm, or about 10 to about 50 ppm), where any lower limit may be combined with any upper limit.

[0048] In non-limiting embodiments, in addition to a lipid feedstock having a chlorine content of at least about 2 ppm, other lipid feedstocks having a chloride content below 2 ppm may also be present during processing. In other embodiments, in addition to a lipid feedstock having a chlorine content of at least about 2 ppm, other lipid feedstocks that are chloride-free may also be present during processing.

[0049] In exemplary embodiments, the lipid feedstock may be pretreated. Suitable pretreatments include, but are not limited to, degumming, neutralization, bleaching, deodorization, or any combination thereof.

[0050] Catalyst

[0051] In exemplary embodiments, in combination with one or more of the foregoing paragraphs, the particulate catalyst used in the exemplary embodiments described herein may be a metal oxide catalyst supported on an oxide support. Suitable metals in the metal oxide include, for example, Na, K, Mg, Ca, Sr, Cr, Mo, Mn, Fe, Co, Ni, Cu, Zn, Al, rare earth metals, or mixtures thereof. In exemplary embodiments, the metal oxide may be present in an amount ranging from about 0.1 to about 10 wt.%. In one exemplary embodiment, a suitable oxide support may be any suitable inorganic oxide support. Representative examples of such suitable oxide supports include, but are not limited to, alumina, silica, silica-alumina, titania, zirconia, or mixtures thereof. In one embodiment, the oxide support is one of alumina and silica-alumina (where the silica content of the silica-alumina support may range from about 2 to about 30 wt.%). The alumina may be any alumina conventionally used in hydrotreating catalysts. Such alumina is typically porous amorphous alumina having an average pore size of about 50 to about 200 angstroms.

[0052] The metal oxide catalyst may be in any conventional catalyst shape known in the art, such as spheres, granules, pellets, fragments, rings, extrudates, or powders.

[0053] In exemplary embodiments, in combination with one or more of the foregoing paragraphs, the particulate catalyst used herein is a small particulate catalyst. The term "small particulate catalyst" as used herein shall be understood to mean a catalyst having an average particle diameter of about 0.05 to about 4 millimeters (mm), or about 0.05 to about 2 mm, or about 0.06 to about 0.5 mm, or even about 100 microns. Any of the foregoing lower limits may be combined with any of the foregoing upper limits.

[0054] Reaction of renewable feedstocks

[0055] To provide a renewable feedstock suitable for refining operations, a lipid feedstock is reacted, under reaction conditions, with a particulate catalyst (such as a metal oxide catalyst on an oxide support), to produce a treated stream comprising a liquid fraction containing bio-oil. The bio-oil has a lower content of free fatty acids and impurities compared to the lipid feedstock. The resulting bio-oil is particularly suitable as a renewable feedstock for hydrotreating in the manufacture of biofuels.

[0056] Without being bound by theory, the reaction is believed to proceed via a thermochemical process, including one or more cracking, decarboxylation, decarboxylation coupling, dehydration, and / or deoxygenation reactions.

[0057] In an exemplary embodiment, which may be combined with one or more of the foregoing paragraphs, the reaction conditions suitable for the lipid feedstock may include one or more of the following: a temperature in the range of about 400 °C to about 700 °C (e.g., about 425 °C to about 650 °C, or about 450 °C to about 600 °C); a pressure in the range of about 0 to about 10 MPa (e.g., about 0.1 to about 5 MPa, or about 0.1 to about 1 MPa); a liquid hourly space velocity (LHSV) in the range of about 0.1 to about 10 h -1 (e.g., about 0.2 to about 5 h -1 , or about 0.3 to about 3 h -1 ). Any of the foregoing lower limits may be combined with any of the upper limits.

[0058] In an exemplary embodiment, which may be combined with one or more of the foregoing paragraphs, the reaction of the lipid feedstock with the particulate catalyst may be carried out in the presence of a gas-based feed stream. Suitable gases include, for example, hydrogen, nitrogen, carbon dioxide, H2O (steam), or C1-C4 hydrocarbons (e.g., methane, ethane, propane, or mixtures thereof). These gases may be incorporated into the reaction mixture of the lipid feedstock and the particulate catalyst, and / or formed during the reaction. A carrier gas may be used to remove gaseous or volatile reaction products, such as carbon dioxide (CO2) and H2O (steam), from the product mixture.

[0059] In an exemplary embodiment, which may be combined with one or more of the foregoing paragraphs, the reaction of the lipid feedstock with the fluidized particulate catalyst may be carried out in any suitable reactor or reactor configuration, such as a fluidized bed reactor, a boiling bed reactor, a riser reactor, or a combination of a riser and a fluidized bed. The feed stream may be injected onto the catalyst as a liquid, vapor, or mixed phase. The feed stream may be preheated before introduction.

[0060] In an exemplary embodiment, which may be combined with one or more of the foregoing paragraphs, the process may be a continuous process.

[0061] In an exemplary embodiment, the bio-oil has a lower content of oxygen and impurities compared to the lipid feedstock.

[0062] In example embodiments, the total acid number (TAN) of the resulting treated stream comprising a liquid fraction (comprising bio-oil) can be less than 5 mg KOH / g (e.g., less than 4 mg KOH / g, less than 3 mg KOH / g, less than 2 mg KOH / g, or less than 1 mg / KOH / g).

[0063] In example embodiments, the resulting treated stream comprising a liquid fraction (comprising bio-oil) can contain less than about 10 ppm (e.g., less than about 5 ppm, or less than about 1 ppm, or less than about 0.5 ppm) of chlorine, calculated as elemental chlorine (Cl atoms).

[0064] In example embodiments, the resulting treated stream comprising a liquid fraction (comprising bio-oil) can contain, calculated as elemental metals, a total of less than 1 ppm, preferably less than about 0.5 ppm, of alkali metals, alkaline earth metals, Group VIIB and VIIIB metals of the periodic table (other metals), or combinations thereof.

[0065] In example embodiments, the oxygen content of the bio-oil, on a dry basis and based on the total weight of the bio-oil, can be 5 wt.% or less (e.g., 3 wt.% or less, or 2 wt.% or less).

[0066] The oxygen content can be determined using ASTM D5291. The oxygen content of the lipid feedstock, on a dry basis and based on the total weight of the feedstock, can range from about 10 to about 15 wt.%.

[0067] As will be described below, the bio-oil obtained is particularly suitable as a renewable feedstock for hydrotreating in the production of biofuels after further treatment.

[0068] Hydrotreating

[0069] Advantageously, the bio-oil produced by the processes of the example embodiments disclosed herein can be used directly as a refinery feedstock. The bio-oil obtained can be blended with one or more mineral oil feedstocks derived from crude oil, shale oil, or coal and also used as a refinery feedstock.

[0070] If desired, the bio-oil can be subjected to a catalytic hydrotreating step. At least one effluent obtained (hydrotreating product) can be fractionated in a fractionation step to provide hydrocarbon fractions suitable as renewable fuels or fuel components, which can be used as transportation fuels, fuel components, and other chemicals. The catalytic hydrotreating step can be carried out in one step or in multiple steps.

[0071] The catalytic hydrotreating step can be carried out by treating one or more fractions of the bio-oil (such as distillation fractions) separately, or the bio-oil can be treated as a whole.

[0072] The catalytic hydrotreating may at least include a hydrodeoxygenation step. The catalytic hydrotreating may include a hydrodeoxygenation step followed by one or more operations selected from hydroisomerization and hydrocracking steps.

[0073] The hydrotreating may be carried out using one or more hydrotreating catalysts, which contain one or more metals selected from Group VIA and Group VIII. Particularly useful examples are Mo, W, Co, Ni, Pt, and Pd. The catalyst may also contain one or more support materials, such as zeolite, alumina, silica-alumina, zirconia, silica-alumina-zeolite, and activated carbon. Suitable are mixtures of CoO and MoO3 (CoMo) and / or mixtures of NiO and MoO3 (NiMo), and / or mixtures of Ni, Mo, and Co and / or NiW, and one or more support materials selected from zeolite, alumina, silica, zeolite-alumina, silica-alumina, silica-alumina-zeolite, and activated carbon. In addition, noble metals dispersed on alumina, such as Pt and / or Pd, may also be used.

[0074] The hydrotreating conditions may include a temperature of about 100 °C to about 450 °C (e.g., about 200 °C to about 370 °C, or about 230 °C to about 350 °C); a pressure of about 0.5 to about 30 MPa (e.g., about 3 to about 25 MPa, or about 3 to about 12 MPa); a liquid hourly space velocity of about 0.01 to about 10 h 3 / m 3 (e.g., about 1300 to about 2200 Nm 3 / m 3 ).

[0075] The hydrotreating is carried out in a reaction stage. The reaction stage may include one or more reactors or reaction zones, each reactor or reaction zone containing one or more catalyst beds of the same or different catalysts. Although other types of catalyst beds / reactors may be used, a fixed bed is preferred. Other types of catalyst beds include fluidized beds, ebullated beds, slurry beds, and moving beds. Interstage cooling or heating may be carried out between reactors, reaction zones, or between catalyst beds within the same reactor.

[0076] At least one effluent of the hydrotreating is discharged from the last reactor. In one embodiment, the effluent is directed to a separator, such as any suitable separator or flash unit. In the separator, typically water, a gaseous stream containing hydrogen, light hydrocarbons (e.g., C1 to C5 hydrocarbons), H2S, CO, and CO2 is separated from a liquid component containing >C5 hydrocarbons and some C1 to C5 hydrocarbons. Water and gas may also be separated by other methods well known to those skilled in the art.

[0077] The liquid hydrocarbon stream obtained from the hydrotreating step contains fuel-grade hydrocarbons with a boiling point of up to 380 °C, in accordance with ISOEN 3405. A person skilled in the art can change the distillation conditions and, if necessary, change the temperature cut-off point to obtain any suitable hydrocarbon product with a boiling point appropriately within the range of transportation fuels.

[0078] Non-limiting example embodiments of the present disclosure will now be further described in conjunction with the accompanying drawings, which may be combined with one or more of the foregoing paragraphs. Referring now more particularly to the drawings, Figure 2 a system 200 is shown, which includes a fluidized bed reactor 210 and a catalyst regeneration unit 220 located outside the fluidized bed reactor 210. It should be understood that the fluidized bed reactor 210 and the catalyst regeneration unit 220 are not limited to Figure 2 the configuration of the illustrated embodiment, and other configurations are contemplated herein. Generally, the fluidized bed reactor 210 represents that a lipid feedstock can be introduced into the fluidized bed reactor 210 through line 230. In an example embodiment, the lipid feedstock is introduced into the fluidized bed reactor 210 through line 230, in the form of a spray via a spray nozzle 235 or by any other suitable means for introducing the lipid feedstock into the fluidized bed reactor 210. However, it should be understood that the fluidized bed reactor 210 can be designed with two or more feed injection points, i.e., at least one for one lipid feedstock and at least one for another lipid feedstock, or these feedstocks can be co-injected (by mixing them upstream of the injection point). The particulate catalyst is injected into the fluidized bed reactor 210 from the catalyst regeneration unit 220 through line 260, which, as discussed below, is a hot regenerated particulate catalyst, i.e., the regenerated particulate catalyst is at an elevated temperature relative to the temperature of the spent catalyst. A gaseous stream introduced through line 245 is used to fluidize the hot regenerated particulate catalyst in the fluidized bed reactor 210 to form a hot regenerated fluidized particulate catalyst. The gaseous stream can include, for example, hydrogen, nitrogen, carbon dioxide, H2O (steam or vapor), C1-C4 hydrocarbons (e.g., methane, ethane, propane, or mixtures thereof), water, or light off-gases separated from the reactor effluent, and optionally steam, and can be superheated in order to provide a heat input to the otherwise adiabatic reactor.

[0079] The gaseous stream introduced into the fluidized bed reactor 210 and / or the catalyst regeneration unit 220 through line 245 can be saturated. For example, the pressure range of the saturated steam can be from about 40 psi to about 150 psi. Alternatively, the gaseous stream introduced into the fluidized bed reactor 210 and / or the catalyst regeneration unit 220 through line 245 can be superheated. The pressure range of the superheated gaseous stream can range from as low as about 40 psi to as high as about 150 psi. The temperature of the superheated gaseous stream through line 245 can be from about 300 °F to about 500 °F.

[0080] In an exemplary embodiment, a lipid feedstock and a hot regenerated fluidized particulate catalyst are subjected to the above reaction conditions, e.g., a temperature of about 400 °C to about 700 °C, a pressure of about 0 to about 10 MPa; a liquid hourly space velocity (LHSV) of about 0.1 to about 10 h -1 -1, a duration of about 10 minutes to about 10 hours, or about 10 minutes to about 5 hours, or about 10 minutes to about 45 minutes. In the fluidized bed reactor 210, the lipid feedstock is treated with the hot regenerated fluidized particulate catalyst to provide a hot reactor effluent comprising a liquid fraction (comprising bio-oil) which has a lower content of free fatty acids and impurities compared to the lipid feedstock. The hot reactor effluent leaves the fluidized bed reactor 210 via line 265 and is sent to a main fractionation tower (not shown).

[0081] During the reaction, when the lipid feedstock contacts the hot regenerated fluidized particulate catalyst, coke is formed in the fluidized bed reactor 210 by catalytic or thermal processes. The formed coke may deposit on the surface of the hot regenerated fluidized particulate catalyst, thereby forming a spent catalyst comprising the particulate catalyst and coke deposits, i.e., coked catalyst particles. The spent catalyst is continuously introduced into the catalyst regeneration unit 220 via line 240, where the spent catalyst is subjected to decoking conditions to burn off most (if not all) of the coke from the spent catalyst and provide a hot regenerated fluidized particulate catalyst. The coke from the spent catalyst can be burned off by exposing the spent catalyst to a stream of oxygen-containing gas (e.g., an inert gas / air via line 250 or a steam / air mixture via lines 245 and 250) under appropriate high temperature and time duration conditions to combust and substantially remove all coke deposits from the catalyst. In an exemplary embodiment, the temperature range can be from about 450 °C to about 1000 °C and the time range can be from about 10 minutes to about 600 minutes. Thus, regenerating the spent catalyst generally involves burning the spent catalyst in an oxidizing atmosphere to burn off the coke deposits and redispersing the active metals on the catalyst particles. Decoking is an exothermic process and can provide the heat required for the reaction process. In a heat balanced operation, the amount of coke formed on the catalyst is large enough such that no external heat source or fuel is required to supplement the heat generated by coke combustion.

[0082] If the amount of coke on the spent catalyst is insufficient and additional energy is required to heat the spent catalyst before recycling it to the fluidized bed reactor 210, additional fuel can be provided in the catalyst regeneration unit. In an exemplary embodiment, optional auxiliary fuel can be further introduced into the catalyst regeneration unit 220 via line 255 to provide additional heat to the catalyst regeneration unit 220. The optional auxiliary fluid can include, for example, light byproduct gases formed during the reaction of the lipid feedstock with the hot regenerated fluidized particulate catalyst in the fluidized bed reactor 210. Representative examples of light byproduct gases include, but are not limited to, carbon monoxide (CO) and hydrogen, as well as light hydrocarbons (e.g., methane, ethane, ethylene, propylene, propane, etc.).

[0083] Coke burning heats the spent catalyst to an elevated temperature, e.g., a temperature of about 450 °C to about 1000 °C, to provide a hot regenerated particulate catalyst that is substantially coke-free or coke-less, where the catalyst particles are heated. The hot regenerated particulate catalyst is continuously introduced into the fluidized bed reactor 210 via line 260, where it is fluidized to form a hot regenerated fluidized particulate catalyst. The heat generated by coke burning in the catalyst regeneration unit 220 is continuously transferred to the fluidized bed reactor 210 along with the hot regenerated particulate catalyst. During coke burning, flue gas is continuously discharged from the catalyst regeneration unit 220 via line 270. By continuously introducing the hot regenerated particulate catalyst into the fluidized bed reactor 210, the lipid feedstock can be introduced into the fluidized bed reactor 210 at a temperature lower than the above reaction temperature.

[0084] Although Figure 2 not shown in the figures, it is understood that measures have been taken to prevent the fluidized particulate catalyst from being carried out of the fluidized bed reactor 210 with the reactor effluent or out of the catalyst regeneration unit 220 with the flue gas. These measures can include gas cyclones that retain the fluidized particulate catalyst in the reactor / catalyst regeneration unit, possibly supplemented with additional cyclones and other dust removal measures such as mechanical filters, filter bags, and / or electrostatic filters for purifying the flue gas from the catalyst regeneration unit and removing dust from the reactor effluent.

[0085] Now the non-limiting exemplary embodiments of the present disclosure will be further described in connection with Figure 3 which can be combined with one or more of the foregoing paragraphs, Figure 3System 300 is shown, which includes a riser 310 feeding into a fluidized bed reactor 320, and a catalyst regeneration unit 330 located external to the riser 310 and the fluidized bed reactor 320. In an exemplary embodiment, the riser 310 is operably connected to the bottom of the fluidized bed reactor 320. This exemplary embodiment uses a reactor called a riser, which is essentially a pipe where the lipid feedstock entering through line 340 is mixed with the hot regenerated particulate catalyst from the catalyst regeneration unit 330 through line 345. In an exemplary embodiment, the period of time that the lipid feedstock and the hot regenerated particulate catalyst are present in the riser 310 ranges from about 5 seconds to about 60 seconds.

[0086] In an exemplary embodiment, the lipid feedstock and the hot regenerated particulate catalyst can be introduced into the riser 310 at the bottom of the riser 310 in the presence of a gaseous stream introduced through line 355, where the gas flow rate is high enough to pneumatically convey the hot regenerated particulate catalyst together with the lipid feedstock through line 350 into the fluidized bed reactor 320, where the catalyst is fluidized as described above to allow the reaction of the lipid feedstock and the hot regenerated fluidized particulate catalyst to proceed to completion. The gaseous stream can serve to inhibit coke formation and can also be used to increase heat by superheating the steam. Injecting the superheated gaseous stream can reduce the amount of regenerated fluidized particulate catalyst required as an energy supply. The absence of the gaseous stream can increase coke formation, which can be beneficial as the coke is used as fuel in the catalyst regeneration unit 330. If additional energy is required to heat the fluidized particulate catalyst before recycling it to the fluidized bed reactor 320 in the case of insufficient coke production, additional fuel can be provided in the catalyst regeneration unit 330 through line 365 as described above.

[0087] In an exemplary embodiment, the lipid feedstock and the hot regenerated fluidized particulate catalyst are subjected to the above reaction conditions, for example, a temperature of about 400 °C to about 700 °C, a pressure of about 0 to about 10 MPa; a liquid hourly space velocity (LHSV) of about 0.1 to about 10 h-1, a duration of about 10 minutes to about 10 hours, or about 10 minutes to about 5 hours, or about 10 minutes to about 45 minutes. Inside the fluidized bed reactor 320, the lipid feedstock is treated with the hot regenerated fluidized particulate catalyst to provide a hot reactor effluent containing a liquid fraction (including bio-oil), which has a lower content of free fatty acids and impurities compared to the lipid feedstock. The hot reactor effluent leaves the fluidized bed reactor 320 through line 370 and is sent to a main fractionation column (not shown).

[0088] During the reaction process, when the lipid feedstock contacts the hot regenerated fluidized particulate catalyst, coke is formed in the fluidized bed reactor 320 through catalytic or thermal processes. The formed coke can deposit on the surface of the hot regenerated fluidized particulate catalyst, thereby forming a spent catalyst containing the particulate catalyst and coke deposits, i.e., coked catalyst particles. The spent catalyst is continuously introduced into the catalyst regeneration unit 330 through line 375, where the spent catalyst undergoes decoking conditions to burn off most (if not all) of the coke from the spent catalyst and provide hot regenerated particulate catalyst. Coke can be burned off from the spent catalyst by exposing the spent catalyst in the catalyst regeneration unit 330 to a stream containing an oxygen source (such as air introduced through line 360) and optionally steam introduced through line 355. During the decoking process, flue gas is continuously discharged from the catalyst regeneration unit 330 through line 80. The hot regenerated particulate catalyst is continuously introduced into the riser 310 through line 345, where it is fluidized to form a hot regenerated fluidized particulate catalyst for further reaction of the lipid feedstock. By continuously introducing the hot regenerated particulate catalyst into the riser 310, the lipid feedstock can be introduced into the fluidized bed reactor 320 at a temperature lower than the above reaction temperature.

[0089] Now, non-limiting example embodiments of the present disclosure will be further described in connection with Figure 4 one or more of the foregoing paragraphs, Figure 4 System 400 is shown, which includes a riser 410 feeding into a fluidized bed reactor 420 and a catalyst regeneration unit 430 located external to the riser 410 and the fluidized bed reactor 420. In an example embodiment, the riser 410 is operably connected to the top of the fluidized bed reactor 420. This example embodiment uses a reactor called a riser, which is essentially a pipe in which the lipid feedstock entering through line 440 is mixed with the hot regenerated particulate catalyst from the catalyst regeneration unit 430 through line 445. In an example embodiment, the lipid feedstock and the hot regenerated particulate catalyst are present in the riser 410 for a period ranging from about 5 seconds to about 60 seconds.

[0090] In an exemplary embodiment, the lipid feedstock and the hot regenerated particulate catalyst can be introduced into the riser 410 at the bottom of the riser 410 in the presence of a gaseous feed stream introduced through line 455, wherein the gas flow rate is high enough to pneumatically convey the hot regenerated particulate catalyst together with the lipid feedstock through line 450 into the fluidized bed reactor 420, where the catalyst is fluidized as described above to effect complete reaction of the lipid feedstock and the hot regenerated fluidized particulate catalyst. In an exemplary embodiment, the fluidized bed reactor 420 further includes line 490 for receiving another gaseous feed stream to assist in fluidizing the particulate catalyst. The gaseous feed stream can serve to inhibit any coke formation and can also be used to increase heat by superheating the steam. Injecting superheated steam can reduce the amount of regenerated fluidized particulate catalyst required as an energy source. The absence of a gaseous feed stream can increase coke formation, which can be beneficial since the coke is used as fuel in the catalyst regeneration unit 430. If additional energy is required to heat the fluidized particulate catalyst prior to recycling it to the fluidized bed reactor 420 in the case of insufficient coke production, additional fuel can be provided in the catalyst regeneration unit 430 through line 465 as described above.

[0091] In an exemplary embodiment, the lipid feedstock and the hot regenerated fluidized particulate catalyst are subjected to the reaction conditions described above, e.g., a temperature of from about 400 °C to about 700 °C, a pressure of from about 0 to about 10 MPa; a liquid hourly space velocity (LHSV) of from about 0.1 to about 10 h-1, a duration ranging from about 10 minutes to about 10 hours, or from about 10 minutes to about 5 hours, or from about 10 minutes to about 45 minutes. Inside the fluidized bed reactor 420, the lipid feedstock is treated with the hot regenerated fluidized particulate catalyst to provide a hot reactor effluent comprising a liquid fraction (comprising bio-oil) having a lower content of free fatty acids and impurities compared to the lipid feedstock, and the hot reactor effluent exits the fluidized bed reactor 420 through line 470 and is sent to a main fractionation tower (not shown).

[0092] During the reaction process, when the lipid feedstock contacts the hot regenerated fluidized particulate catalyst, coke is formed in the fluidized bed reactor 420 through catalytic or thermal processes. The formed coke can deposit on the surface of the hot regenerated fluidized particulate catalyst, thereby forming a spent catalyst comprising the particulate catalyst and a coke deposit, i.e., a coked catalyst particle. The spent catalyst is continuously introduced into the catalyst regeneration unit 430 through line 475, where the spent catalyst undergoes decoking conditions to burn off most (if not all) of the coke from the spent catalyst and provide a hot regenerated fluidized particulate catalyst. Coke can be burned off from the spent catalyst by exposing the spent catalyst in the catalyst regeneration unit 430 to a stream comprising an oxygen source such as air introduced through line 460 and optionally steam introduced through line 455. During the decoking process, flue gas is continuously discharged from the catalyst regeneration unit 430 through line 480. The hot regenerated particulate catalyst is continuously introduced into the riser 410 through line 445, where it is fluidized to form a hot regenerated fluidized particulate catalyst for further reaction of the lipid feedstock. By continuously introducing the hot regenerated particulate catalyst into the riser 410, the lipid feedstock can be introduced into the fluidized bed reactor 420 at a temperature lower than the above reaction temperature.

[0093] For simplicity, the various features disclosed herein are described in the context of a single embodiment, but may also be provided separately or in any suitable sub-combination. The exemplary embodiments of the present disclosure specifically cover all combinations of embodiments as if each combination were separately and explicitly disclosed. Additionally, all sub-combinations listed in the embodiments describing such variables are also specifically covered by the present combination and are hereby disclosed as if each such sub-combination were separately and explicitly disclosed.

[0094] Although the above description contains many specific details, these specific details should not be construed as limitations on the present disclosure, but merely as examples of its preferred embodiments. Those skilled in the art will envision many other embodiments within the scope and spirit of the present disclosure defined by the appended claims.

Claims

1. A method, comprising: (a) processing a lipid feedstock above a fluidized particulate catalyst in a gas-based stream in a fluidized bed reactor to obtain a processed stream and spent catalyst containing coke deposits; (b) continuously introducing the spent catalyst containing coke deposits into a catalyst regeneration unit; (c) continuously operating the catalyst regeneration unit to burn off the coke deposits from the spent catalyst, thereby obtaining regenerated particulate catalyst; and (d) continuously introducing the regenerated particulate catalyst from the catalyst regeneration unit into the fluidized bed reactor.

2. The method according to claim 1, wherein the lipid feedstock comprises at least one fatty acid glyceride selected from the group consisting of acidulated soapstock, physically refined fatty acid distillates from vegetable oils or animal fats, distilled corn oil from ethanol production, waste cooking oil, lard, brown grease, yellow grease, grease trap grease, waste fat, low grade oil, supercritical water liquefied oil, vegetable oil, animal fat, and any combination thereof.

3. The method according to claim 1, wherein the lipid feedstock comprises fatty acid methyl esters.

4. The method according to claim 1, wherein the lipid feedstock is partially decomposed and / or hydrolyzed.

5. The method according to any one of claims 1-4, wherein the fluidized particulate catalyst comprises a metal selected from the group consisting of Na, K, Mg, Ca, Ba, Sr, Cr, Mo, Mn, Fe, Co, Ni, Cu, Zn, Al, rare earth metals, and any combination thereof, and an oxide support selected from the group consisting of alumina, silica, silica-alumina, titanium oxide, zirconium oxide, and any combination thereof.

6. The method according to any one of claims 1-4, wherein the fluidized particulate catalyst has an average particle size of from about 0.05 to about 4 millimeters (mm).

7. The method according to any one of claims 1-6, wherein processing the lipid feedstock above the fluidized particulate catalyst in the gas-based stream in the fluidized bed reactor is carried out under reaction conditions including one or more of the following: a temperature in the range of from about 400 °C to about 700 °C, a pressure in the range of from about 0.1 to about 10 MPa, and a liquid hourly space velocity in the range of from about 0.1 to about 10 h-1.

8. The method according to any one of claims 1-7, wherein processing the lipid feedstock above the fluidized particulate catalyst in the gas-based stream in the fluidized bed reactor comprises introducing the lipid feedstock and the fluidized particulate catalyst in the gas-based stream at different injection points.

9. The method according to claim 8, wherein introducing the fluidized particulate catalyst in the gas-based stream comprises introducing the regenerated particulate catalyst from the catalyst regeneration unit into the fluidized bed reactor in the presence of steam.

10. The method according to any one of claims 1-9, wherein continuously operating the catalyst regeneration unit to burn off the coke deposits from the spent catalyst comprises introducing an oxygen source into the catalyst regeneration unit in the presence of heat.

11. The method according to claim 10, wherein the spent catalyst is heated to a temperature of from about 450 °C to about 1000 °C to provide a hot regenerated particulate catalyst, and the hot regenerated particulate catalyst is continuously introduced from the catalyst regeneration unit into the fluidized bed reactor.

12. The method according to any one of claims 1-11, wherein the fluidized bed reactor further comprises a riser for an initial contact of the lipid feedstock with the fluidized particulate catalyst in a gas-based stream, wherein the lipid feedstock and the fluidized particulate catalyst pass upwardly together through the riser during start-up processing, and wherein the lipid feedstock and the fluidized particulate catalyst subsequently enter the fluidized bed reactor.

13. The method according to claim 12, wherein the riser is operably connected to the bottom of the fluidized bed reactor.

14. The method according to claim 12, wherein the riser is operably connected to the top of the fluidized bed reactor.

15. The method according to claim 12, wherein the lipid feedstock and the fluidized particulate catalyst are in the riser for a period of from about 5 seconds to about 60 seconds.

16. The method according to any one of claims 1-15, wherein the lipid feedstock is processed over the fluidized particulate catalyst in the gas-based stream in the fluidized bed reactor continuously until completion.

17. The method according to any one of claims 1-16, wherein the gas-based stream comprises one of hydrogen, nitrogen, carbon dioxide, C1 to C4 hydrocarbons, water or a mixture thereof.

18. The method according to any one of claims 1-17, wherein the regenerated particulate catalyst is free of coke deposits.

19. The method according to any one of claims 1-18, wherein the processed stream comprises a gaseous fraction and a liquid fraction comprising bio-oil, wherein the bio-oil has a lower content of oxygen and impurities compared to the lipid feedstock.

20. The method according to claim 19, further comprising a hydrotreating step of the bio-oil to provide a hydrotreated product.

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