Patent Application
20240400909
The present disclosure relates generally to a hydrothermal feedstock treatment process. More particularly, the present disclosure relates to hydrothermal feedstock treatment processes by treatment with direct steam injection.
The ever-increasing demand for renewable fuels and chemicals has forced refineries to look to alternative hydrocarbon sources and ways to upgrade and convert these sources or feedstocks into viable products.
The disclosure provides a process for a hydrothermal feedstock treatment including direct steam injection.
According to one example (“Example 1”), the process includes the step of providing a water feed and a feedstock feed. The feedstock is provided at a temperature of between about 20° C. and 50° C. and a pressure of at least about 0.05 MPa. The water is provided at a temperature of between about 20° C. and 40° C. and a pressure of at least about 0.05 MPa. The feedstock and the water feed are combined at a mix ratio of from 0.1:1 to 1:1 to form a combined feedstock and water feed stream. The combined feedstock and water feed stream may be pressurized to 2 to 8 MPa. The process further includes directly injecting (and condensing) steam at a pressure from 5 to 8 MPa, or about 6 MPa into the combined feedstock and water feed stream. The steam may be injected at a ratio of 0.1:1 to 0.4:1 to form a heated combined feedstock and water feed stream. The temperature of the heated and pressurized combined feedstock and water stream may be from 150 to 280° C. Alternatively, the temperature of the heated and pressurized combined feedstock and water stream may be greater than or equal to 200° C. but less than or equal to 260° C., such as 200-260° C., 220-260° C., 230-260° C., 240-260° C., 210-250° C., or 220-250° C., inclusive.
The heated combined feedstock and water stream may be supplied to a hydrothermal reactor, such as a tank, or a pipe, tube, or high-pressure shell and tube exchanger, optionally heating the stream further to a temperature of from 200° C. and 370° C. The residence time in the reactor is sufficient such that some contaminants are liberated from the feedstock
The reactor is at a temperature of between about 200° C. and 370° C. and the residence time of the heated combined feedstock and water feed stream in the reactor is between about 1 second and 120 minutes, and a product stream formed.
After treatment in the reactor, the product stream is transferred to a post-treatment process. The post-treatment process may include cooling and/or depressurizing the product stream, prior to feeding the product stream into a separator, optionally adding process chemicals, such that phase separation is initiated. The post-treatment process is maintained at a temperature of between about 50° C. and 100° C.
The depressurizing step may involve flashing a portion of a water stream in the cooled product stream to generate steam. The separated water stream may be reheated. An economizer or a plurality thereof may be used to reheat the separated water stream. Economizers are primarily heat transfer surfaces used to preheat boiler feedwater before it enters, for example, a drum or a furnace surface, depending on the boiler design. Economizers typically include a number of tubes. The tubes may have fins or other structures to increase their heat absorption from gas passing over the tubes. The term “economizer” comes from early use of such heat exchangers to reduce operating costs or economize fuel usage by recovering extra energy from flue gas.
The separated water stream can be chemically treated or recycled. The separated water stream may be treated by anaerobic digestion. Anaerobic digestion can be performed in an anaerobic digester, where the environment is an inert atmosphere where oxygen is absent. Anaerobic digestion can be performed in the range 45 to 70° C., 48 to 60° C., 45 to 70° C., 49 to 59° C., or 50 to 55° C., inclusive. The anaerobic digestion process can be performed for a duration of 6 hours to 100 days, 12 hours to 80 days, 1 day to 60 days, 5 days to 40 days, or 10 days to 30 days, inclusive.
According to a second example (“Example 2”), the process includes providing a feedstock feed. The feedstock is provided at a temperature of between about 20° C. and 50° C. and a pressure of at least about 0.05 MPa. Optionally, the feedstock stream may be pressurized to 2 to 8 MPa. The process further includes directly injecting (and condensing) steam at a pressure from 5 to 8 MPa, or about 6 MPa into the feedstock stream. The steam may be injected at a ratio of 0.1:1 to 0.4:1 to form a heated combined feedstock and water feed stream. The temperature of the heated and pressurized combined feedstock and water stream may be from 150 to 280° C. Alternatively, the temperature of the heated feedstock may be greater than or equal to 200° C. but less than or equal to 260° C., such as 200-260° C., 220-260° C., 230-260° C., 240-260° C., 210-250° C., or 220-250° C., inclusive. The heated and pressurized combined feedstock and water stream is supplied to a hydrothermal reactor or high-pressure shell and tube exchanger, and further processed as is described in Example 1.
According to a third example (“Example 3”), a process involving degummed feedstock can substantially reduce the amount of various inorganic compounds, such as metals, in a reactor feedstock, reactor product oil, and centrifuged reactor product oil.
According to another example (“Example 4”), the process can be performed in the absence of a reactor and instead involve providing a water feed and a feedstock feed to a pipe. The feedstock is provided at a temperature of between about 20° C. and 50° C. and a pressure of at least about 0.05 MPa. The water is provided at a temperature of between about 20° C. and 40° C. and a pressure of at least about 0.05 MPa. The feedstock and the water feed are combined at a mix ratio of from 0:1 to 1:1 to form a combined feedstock and water feed stream. The combined feedstock and water feed stream may be pressurized to 2 to 8 MPa. The process further includes directly injecting (and condensing) steam at a pressure from 5 to 8 MPa, or about 6 MPa into the combined feedstock and water feed stream. The steam may be injected at a ratio of 0.1:1 to 0.4:1 to form a heated combined feedstock and water feed stream. The temperature of the heated and pressurized combined feedstock and water stream may be from 150 to 280° C. Alternatively, the temperature of the heated and pressurized combined feedstock and water stream may be greater than or equal to 200° C. but less than or equal to 260° C., such as 200-260° C., 220-260° C., 230-260° C., 240-260° C., 210-250° C., or 220-250° C., inclusive.
The foregoing Examples are just that, and should not be read to limit or otherwise narrow the scope of any of the inventive concepts otherwise provided by the instant disclosure. While multiple examples are disclosed, still other embodiments will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative examples. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature rather than restrictive in nature.
The accompanying drawings are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments, and together with the description serve to explain the principles of the disclosure.
This disclosure is not meant to be read in a restrictive manner. For example, the terminology used in the application should be read broadly in the context of the meaning those in the field would attribute such terminology.
With respect to terminology of inexactitude, the terms “about” and “approximately” may be used, interchangeably, to refer to a measurement that includes the stated measurement and that also includes any measurements that are reasonably close to the stated measurement. Measurements that are reasonably close to the stated measurement deviate from the stated measurement by a reasonably small amount as understood and readily ascertained by individuals having ordinary skill in the relevant arts. Such deviations may be attributable to measurement error, differences in measurement and/or manufacturing equipment calibration, human error in reading and/or setting measurements, minor adjustments made to optimize performance and/or structural parameters in view of differences in measurements associated with other components, particular implementation scenarios, imprecise adjustment and/or manipulation of objects by a person or machine, and/or the like, for example. In the event it is determined that individuals having ordinary skill in the relevant arts would not readily ascertain values for such reasonably small differences, the terms “about” and “approximately” can be understood to mean plus or minus 10% of the stated value.
Persons skilled in the art will readily appreciate that various aspects of the present disclosure can be realized by any number of methods and apparatuses configured to perform the intended functions. It should also be noted that the accompanying drawing figures referred to herein are not necessarily drawn to scale, but may be exaggerated to illustrate various aspects of the present disclosure, and in that regard, the drawing figures should not be construed as limiting.
The processes shown in
The feedstock may include renewable or non-renewable organic feedstock. The feedstock can include glyceride-based lipids, such as triglycerides derived from plant and animal sources, renewable plant oil, algal and microbial oils, waste vegetable oils, brown grease, animal fats; oils from recycled petroleum products, plastics, and elastomers; and petroleum crude oil or crude oil fractions. Animal fats can include lard, tallow, poultry, among others.
The instant process has numerous advantages over other cleanup processes such as chemical degumming, desalting processes, or other chemical, extraction, or thermal processes. Advantages may include a small equipment footprint that can be co-located with a conventional refinery or implemented in the field; the ability to recover valuable aqueous or organic products or byproducts; and incorporation of integral high-energy atmospheric vapor-liquid separation or rectification of the product stream that eliminates the need for vacuum distillation to separate or concentrate products. Additionally, eliminating the need for heat transfer surfaces can significantly reduce energy losses and fouling potential, leading to increased yield and utilization. The process results in a high product yield with significantly reduced concentrations of salts, metals, and minerals, such as silicas, oxides, carbonates, sulfates, and phosphates. The system is desirable for processing renewable feedstocks which are subject to transesterification, esterification, hydrolysis, saponification, and hydrogenation. The system is specifically desirable for use in processing renewable feedstocks which results in renewable diesel.
The process may be a continuous-flow or batch process. The process can involve a reactor, such as a hydrothermal reactor. The reactor can have an outer stainless steel shell and a corrosion-resistant inner liner, such as a liner including PTFE or polypropylene (PPL). The reactor may be a tubular reactor. In some examples, the reactor facilitates a Taylor fluid flow or laminar vortex flow. The reactor can have variable bypasses and irises to control and steer the laminar flow through the reactor chamber. The laminar flow reactor can have a continuous flow design.
Alternatively, the process may not involve a reactor and instead include a tank, pipe, tube, or shell and tube heat exchanger. Whereas a hydrothermal reactor is not typically replaceable by a tank, pipe, tube, or shell and tube heat exchanger, the conditions of the instant feedstock purification process, for example, the laminar flow conditions, allow for such an embodiment.
The feedstock may be renewable or non-renewable organic feedstocks, such as renewable plant oil, algal and microbial oils, waste vegetable oils, brown grease, tallow; oils from recycled petroleum products, plastic, and elastomers; and petroleum crude oil or crude oil fractions. The feedstock may further contain contaminants. The process disclosed herein separates undesirable contaminants such as minerals, metals, salts, and asphaltenes, from the feedstock to produce clean oil. Other contaminants may include mycotoxins, pesticide residues, e.g., organochlorines, organophosphates, or carbamates, polycyclic aromatic hydrocarbons (PAHs), phthalates, solvent residue, antioxidants, or polychlorinated biphenyls (PCBs), among others.
By “clean” it is meant that contaminants in the product have been reduced by greater than 90%, such as by more than 95%, often resulting in trace amounts (near or below typical analytical method detection limits) of contaminants compared to the feedstock. The level of contaminants in the clean oil is minimized to greatly reduce deposition, polymerization, and coking in downstream conversion equipment and deactivation or fouling of downstream conversion catalysts.
The process can involve controlled dissociation of contaminants from feedstock molecules, resulting in the selective release of contaminants while preserving the desired product species. Feedstock contaminants may dissociate from the original molecular structure of the feedstock. Dissociation of contaminants leads to separation and liberation of impurities or undesired species that were previously incorporated into the molecular frameworks of the feedstock. Accordingly, the process may involve collection of contaminants liberated from the molecular structure of a feedstock.
Feedstock may be combined with water, such as water supplied by a water feed, a steam injector, or from each source, prior to entering a reactor, such as a hydrothermal reactor. Prior to steam injection, feedstock can be heated, such as preheated, to a temperature of from 100° C. to 450° C., 100° C. to 400° C., 100° C. to 200° C., 150° C. to 250° C., 150° C. to 350° C., 150° C. to 300° C., 200° C. to 300° C., or 250° C. to 300° C., inclusive.
Steam injection can heat feedstock to a temperature of greater than or equal to 200° C. but less than or equal to 260° C., such as 200-260° C., 220-260° C., 230-260° C., 240-260° C., 210-250° C., or 220-250° C., inclusive. In some examples, feedstock is mixed with water prior to steam injection. Water can be provided by a water feed that is separate from the steam injector. In such case, steam injection can heat a combined feedstock and water stream to a temperature of greater than or equal to 200° C. but less than or equal to 260° C., such as 200-260° C., 220-260° C., 230-260° C., 240-260° C., 210-250° C., or 220-250° C., inclusive.
Steam injection can involve a steam supply pressure of 500 to 1000 psig 500 to 800 psig, 650 to 900 psig, 750 to 1000 psig 800 to 900 psig, or 700 to 900 psig, inclusive. The water feed may or may not be heated and/or pressurized. In the reactor, the heated and pressurized combination of feedstock and water stream are maintained at a laminar flow.
In fluid dynamics, laminar flow is the property of fluid particles to follow layered paths, where each layer moves smoothly past the adjacent layers with little to no mixing. The Reynolds number (Re) is a dimensionless parameter that aids in describing whether a fluid flow is laminar or turbulent by representing the ratio between the inertial forces and the viscous forces acting on the fluid. Laminar flow generally occurs when the fluid is moving slowly or the fluid is highly viscous. In this case, the viscous forces dominate, and the flow is smooth and predictable. As the Reynolds number increases, e.g., by increasing the flow rate of the fluid, the flow will transition from laminar to turbulent flow.
In some examples, disclosed processes may not involve turbulent flow or a fluid flow characterized by a Reynolds number of greater than 2000. Contents of a hydrothermal reactor, such as a heated and pressurized mixture of feedstock and water stream, can have a laminar flow within the hydrothermal reactor, e.g., characterized by a Reynolds number of less than about 2300, 2000, 1750, or 1500. In other examples, a mixture containing feedstock and water stream in the reactor may have a Reynolds number of from 50 to 750, 75 to 1750, 100 to 1650, 250 to 1500, 500 to 2000, 750 to 2000, 1000 to 2000, 500 to 1000, 750 to 1250, 1250 to 1800, or 1500 to 2000, wherein each range is inclusive.
Re may defined as Re=ND2/v, where N is blade rotations per second, D is the impeller diameter and v is the kinematic viscosity of the fluid. Alternatively, Re can be Re=ρVD/μ, where V represents free-stream fluid velocity, D is characteristic distance or pipe diameter, ρ is fluid density, and μ is fluid viscosity (dynamic).
Residence time of reactor contents including feedstock and water can range from 1 second to 120 minutes, optionally between about 5 seconds to 5 minutes, optionally between about 30 seconds to 5 minutes, optionally between about 1 to 3 minutes, optionally between about 1 to 6 minutes, optionally between about 2 to 4 minutes, optionally between about 30 to 60 seconds, optionally between about 1 minutes to 60 minutes, optionally between about 2 minutes to 30 minutes, optionally between about 5 minutes to 15 minutes, or optionally between about 10 seconds to 10 minutes, where each range is inclusive.
Following steam and injection and reaching laminar flow, the heated feedstock, optionally combined with a heated water stream, are immediately cooled, such that cooling occurs immediately after heating without any intervening steps. For example, the heated feedstock and water stream can be cooled less than 180 seconds, 120 seconds, 60 seconds, 30 seconds, or 15 seconds after exiting a reactor, pipe, tube, or other vessel. In other embodiments, such as those that do not involve a reactor, the heated feedstock and water stream can be cooled less than 180 seconds, 120 seconds, 60 seconds, 30 seconds, or 15 seconds after reaching a temperature of 265, 260, 255, 250, 245, 240, 230, 225, or 220° C.
The cooling process can reduce the feedstock temperature from 200-260° C., 220-260° C., 230-260° C., 240-260° C., 210-250° C., or 220-250° C. 230° C.-260° C. to 90° C. or less, 70° C. or less, 50° C. or less, or 30° C. or less over a period of 30 seconds to 15 minutes, 30 seconds to 10 minutes, 30 seconds to 5 minutes, or 30 seconds to 1 minute, where each range is inclusive.
The contaminated feedstocks may be petroleum-based feedstocks, such as petroleum crude oil, shale oil, petroleum refinery intermediate streams (such as ATBs or vacuum tower bottoms (VTB)), pyrolysis oils, recycled plastics, coal liquids, used motor oil, and mixtures thereof. Alternatively, the contaminated feedstock may be renewable feedstock, such as a plant oil. Suitable plant oils for treating according to the present invention include oils of canola, Carinata, castor, Jatropha, palm, Pongamia, soy bean, tung, and/or corn (such as derived from distiller grains), soap stock, waste vegetable oil, yellow grease (from cooking oil), brown grease (from grease traps and wastewater treatment), highly acidic oils (also referred to as acidic oils), animal tallow, algal oil, microbial oil, terpenes and other pine-related byproducts from tall oils, or other biosynthetic oils (such as derived from pyrolysis, esterification, oligomerization, or polymerization) and mixtures thereof.
The feedstock can include an acidic oil. The acidic oil can be alternatively referred to as an acid oil or an acidulated soapstock. Alkali refining of a crude oil results in a soapstock, which then undergoes an acidulation step, for example, with sulfuric acid, to convert the soap into free fatty acids, thereby forming the acidulated soapstock or acid oil product. Acidulated soapstock is typically rich in free fatty acids relative to crude oil. In one illustrative example of differentiating a plant acid oil from a plant oil feedstock, soybean acid oil is derived from the soapstock byproduct generated during the alkali refining process of crude soybean oil, while soybean oil itself is the main product extracted from soybeans.
The feedstock may contain less than 5%, less than 10%, less than 15%, or less than 20% of an acid oil. For example, the feedstock can contain an acid oil in a total amount of about 1-5%, 1-10%, 1-15%, 10-19%, or 15-19%. Alternatively, the feedstock may contain an acid oil in an amount of greater than 80%, greater than 85%, greater than 90%, or greater than 95%. For example, the feedstock can contain an acid oil in a total amount of 80-100%, 80-90%, 85-95%, 90-100%, or 96-100%.
Contaminants that may be removed include inorganic materials, such as halides (e.g., CI, Br, I) phosphorus and phosphorus-containing species, alkali metals and metalloids (e.g., B, Na, K, Si), and other metals (e.g., Ca, Fe, Mg, Ni, V, Zn). Organic contaminants for removal may include asphaltenes, polymers (such as polyesters and/or polypropylenes), high molecular weight organic compounds or waxes (such as containing more than 50-60 carbon atoms and/or having a boiling point greater than 600° C.), petroleum coke (petcoke), and/or coke precursors. The process may result in clean oil by achieving more than 90% (such as more than 95%) reduction in phosphorus, salt, mineral, and metal content relative to the starting material. In phospholipid feedstocks, phosphorus content is reduced from thousands of parts per million (ppm) to less than 100 ppm at a fraction of the yield loss associated with conventional degumming.
The process can result in a treated oil that has less than about 10 ppm, 5 ppm, 1 ppm, 0.5 ppm, or 0.1 ppm of a contaminant. The process may result in a treated oil that has at least 50%, 100%, 250%, 500%, 750%, or 1000% less of a contaminant relative to the original feedstock oil. The process may result in a treated oil that has from about 1 to 50%, 50 to 100%, 80 to 125%, 90 to 100%, 75 to 150%, or 100 to 200%, less of a contaminant relative to the original feedstock oil.
The process may involve use of feedstocks that have undergone phospholipid removal, such as by degumming or another treatment method. Exemplary degumming methods include water degumming, enzyme assisted water degumming, acid degumming, and combinations thereof.
In the water degumming process, water is added to a feedstock, such as a crude oil, and the feedstock and water are mixed together to aid the hydration of the phospholipids present in the feedstock. The hydration of the phospholipids or “gums” causes the gums to swell and agglomerate as a flocculent, which is subsequently separated from the remainder of the feedstock. The feedstock obtained from this technique is generally referred to as “degummed,” despite being only partially degummed. For example, water degummed oil may still contain a high amounts of phospholipids, especially non-hydratable phospholipids. In such cases, water degumming can be combined with other degumming or processing techniques, such as caustic refining or phospholipase A (PLA) enzyme degumming, to produce a feedstock of improved stability and color.
Enzymatic degumming, also referred to as enzymatic refining may be employed for total removal of phospholipids, e.g., alone or in combination with other degumming treatments. Enzymatic degumming involves an enzymatic dismemberment of phospholipid constituents, such as fatty acids or phosphate derivatives. This transformation of phospholipids in a feedstock alters its emulsification properties such that less oil is lost when the gums are separated from the oil, e.g., relative to water degumming. Phospholipase enzymes are primarily involved in enzymatic degumming. Exemplary phospholipases include phospholipase A1 (PLA1), phospholipase A2 (PLA2), phospholipase C (PLC), phospholipase D (PLD), and combinations thereof. PLC is capable of cleaving phosphate groups, and PLA cleaves fatty acid groups. Selection of an enzyme for enzymatic degumming of a feedstock can be guided by the content of the feedstock, such as the phospholipid composition, the desired level of degumming, and processing conditions, such as temperature and pH, which can affect enzyme activity.
Water and enzyme degumming strategies can be combined for enzyme-assisted water degumming or enzymatic water degumming, which can be used to degum feedstocks containing a high amount of hydratable phospholipids. This approach can be used to react the hydratable phospholipids, converting them into diacylglycerols, while maintaining the non-hydratable phospholipids in the feedstock, such as crude oil. Enzymes utilized for this process include PLC and phosphatidyl inositol phospholipase (PI-PLC). In an illustrative example of the enzyme-assisted water degumming process, water and PLCs are added to crude oil with mixing. The enzymes react with the phospholipids in the oil with shear mixing to aid in the conversion of phosphatidyl choline (PC), phosphatidyl ethanolamine (PE), to diacylglycerols in the oil. The heavy phase (water, denatured protein, and phosphor-compounds) has a specific gravity higher than that of the oil and may be separated by settling, filtration, or the industrial practice of centrifugation. The enzyme-assisted water degumming process predominately removes the hydratable phospholipids. The remaining phospholipids, e.g., measured as the salts of phosphatidic acid can be removed in subsequent processing operations.
In a further example, acid degumming can be applied to a feedstock, such as a crude oil, for substantial removal of phospholipids. For example, crude oil may be treated with phosphoric acid, citric acid, malic acid, formic acid, acetic acid, or a combination thereof. The acid improves the hydrophilic nature of the non-hydratable phospholipids, thus aiding in their removal. Water is then added to the acid-treated crude oil, and the oil is mixed to aid the hydration of the phospholipids. The hydration of the phospholipids or “gums” causes the gums to swell and agglomerate as a flocculent, which is subsequently removed. The acid degumming process removes most of the phospholipids but may require additional processing. As in the water degumming process, some oil is entrained and considered a process loss.
Feedstock may contain chlorophyll. For example, triacylglycerol oils from oilseeds such as soybean and canola, and oil fruits, such as palm and algal source oils, contain chlorophyll. Even though several steps in a typical oil production process can result in the removal of chlorophyll, including seed crushing, oil extraction, degumming, caustic treatment, and bleaching, chlorophyll can persist in a feedstock.
Low levels of chlorophyll are advantageous because chlorophyll pigments can impart an undesirable color and induce oxidation of oil during storage, thereby undermining storage stability and promoting deterioration. In the edible oil processing industry, a bleaching step is employed to lower chlorophyll levels to as low as 0.02 ppm to guarantee oil quality in terms of color and organolepticity. This bleaching step increases processing cost and reduces oil yield due to entrainment in the bleaching clay. The “spent” clay then must be disposed of in an environmentally conscious manner and precaution must be taken during transport, as spontaneous combustion is a risk of acid-treated material and adsorbed oil.
Treatment of a feedstock containing chlorophyll in accordance with disclosed processes can reduce the amount of chlorophyll in the treated feedstock to levels of less than about 200 ppb, 150 ppb, 100 ppb, 50 ppb, or 25 ppb. For example, treated feedstock may contain chlorophyll in an amount of 1 to 150 ppb, 10 to 100 ppb, 25 to 75 ppb, 30 to 50 ppb, 15 to 30 ppb, 1 to 25 ppb, or 5 to 15 ppb, wherein each range is inclusive. In some embodiments, disclosed processes do not involve bleaching of either a feedstock or a treated feedstock.
The system disclosed herein may include a high-temperature, high-pressure, hydrothermal reactor system coupled with components for separation and/or recovery of a clean oil product. The process may be operated in a manner that produces a clean petroleum crude oil fraction, clean glycerides from renewable feedstocks, and/or clean distillate fractions from petroleum or renewable oils. For example, the concentration of inorganic contaminants is reduced to the degree that the resultant clean oils may be effectively upgraded using conventional refinery hydroprocessing operations (hydrotreating, hydrocracking, and/or hydroisomerization) with reduced coke formation, reduced catalyst fouling, and reduced catalyst deactivation. Effluent streams may be recovered, recycled, or refined to recover valuable byproducts.
In addition to degumming crude feedstock, additional refining or purification processes may also be performed on crude feedstock or feedstock treated in accordance with the processes described herein.
Additional refining or purification processes may include any of neutralization, such as to remove free fatty acids, bleaching, e.g., to remove color and other contaminants, deodorization, such as to remove undesirable odors and flavors, and winterization or dewaxing to remove waxes or improve cold stability. Selective removal of certain compounds may also be performed, such as the selective hydrolysis of triglycerides.
Gums can contribute to refining losses and darken feedstock as they decompose due to their thermal instability. Whereas degumming can remove hydratable and non-hydratable gums from a feedstock, such as a plant oil, neutralization is a separate step that occurs after degumming to neutralize free fatty acids (FFA) present in the oil. Neutralization can involve adding an alkalizing agent, such as caustic lye, to neutralize a contaminant. In one example, neutralization of FFAs transforms them into soap that can be separated from oil. Such processes can also contribute to the elimination of non-hydratable gums and metals.
Deodorization can involve steam deodorization, which transports high-temperature steam to the surface of oil or grease to combine the water vapor with the odorous substances. Through the upward transpiration of the water vapor, the odorous substances escape from the grease, thereby deodorizing the oil.
Feedstock treatment processes may be performed after or immediately following an extraction process. For example, in the solvent extraction process, the final removal of solvent from the oil is achieved in the oil stripper. The feedstock treatment processes could be performed on the oil immediately following final removal of hexane in the oil stripper. Exemplary extraction processes include but are not limited to steam distillation, organic solvent extraction, and supercritical CO2 fluid extraction methods, and molecular distillation techniques. Some products of extraction can contain an amount of wax components so large that their removal is necessitated, e.g., by dewaxing processes. For illustrative purposes, the waxes in essential oils are higher aliphatic hydrocarbons, which can increase the cloud point of essential oils, reduce transparency, hinder the volatilization of aroma components, and reduce overall quality.
Referring to
In one embodiment, the process may also include providing water feed 104. A pump 105 may be provided for supplying water feed 104. In some embodiments the water feed 104 is heated to a temperature of greater than about 30° C., optionally between about 100 and 175° C., alternatively between about 50 and 75° C., or between about 20 and 50° C. In certain embodiments, water feed 104 is pressurized to a pressure of between about 1 and 10 MPa, alternatively to a pressure of between about 1 and 5 MPa.
The feedstock 102 and the water feed 104 are combined to form a combined feedstock and water stream 106. Feedstock 102 and water feed 104 can be combined by known means, such as for example, a valve, tee fitting or the like. The combined feedstock and water feed stream 106 is pressurized to a pressure of between about 1 to 10 MPa, 3 to 10 MPa, 3 to 6 MPa, 2 to 8 MPa, or alternatively to a pressure of between about 1 and 5 MPa. Optionally, feedstock 102 and water feed 104 can be combined in a larger holding vessel (not shown) that is maintained at a temperature of from between about 200 and 300° C. and pressure of between to 2 to 8 MPa. Optionally, the feedstock 102 and water feed 104 can be supplied to a larger vessel that includes mixing means, such as a mechanical stirrer, or the like. In certain embodiments, feedstock 102 and water feed 104 are thoroughly mixed at the point where they are combined. The mass ratio of feedstock 102 and water feed 104 can be between about 0:1 and 10:1, optionally between about 0:1 and 5:1, optionally between about 0:1 and 2:1, or optionally between about from 0:1 and 1:1.
The process further includes directly injecting steam 108 into the combined feedstock and water stream 106. The steam 108 may be provided at a pressure of from 1 to 10 MPa, 3 to 10 MPa, 3 to 7 MPa, 5 to 10 MPa, or from 5 to 8 MPa, or alternatively, at about 6 MPa. The direct steam injection 108 accomplishes heat transfer to the combined feedstock and water feed stream 106 traveling through the pipeline and forming the heated combined feedstock and water feed stream 110. The combined feedstock and water stream 106 is heated upon contact with steam 108 that is directly injected into the combined feedstock and water stream 106. Upon injection, the steam mixes with the combined feedstock and water stream 106. Further, the combined feedstock and water stream 106 is heated by the condensation of steam 108.
The mass ratio of steam 108 to combined feedstock and water feed 106 can be between about 0.1:10 and 10:0.1, optionally between about 0.1:5 and 5:0.1, optionally between about 0.1:1 and 0.4:1.
The ratio of water to feedstock in the combined feedstock and water 106 includes the steam injected and condensed and added by water feed 104.
The temperature of the heated and pressurized combined feedstock and water feed stream 110 may be from 50 to 280° C., optionally between about 80 and 200° C., alternatively between about 90 and 180° C., or between about 100 and 150° C.
The heated combined feedstock and water feed stream 110 is supplied to a hydrothermal reactor 112. Hydrothermal reactor 112 can be a known type of reactor, such as, a tubular type reactor, vessel type reactor, optionally equipped with stirrer, or the like. Hydrothermal reactor 112 can be horizontal, vertical or a combined reactor having horizontal and vertical reaction zones. Hydrothermal reactor 112 preferably does not include a solid catalyst. Hydrothermal reactor 112 can include one or more heating devices, such as for example, a strip heater, immersion heater, tubular furnace, or the like, as known in the art, heating the incoming stream 110 further to a temperature of from 200° C. and 370° C.
The temperature of hydrothermal reactor 112 can be between about 200 to 370° C., optionally between about 250 to 350° C., or optionally between about 220 to 250° C. The residence time of heated and pressurized combined feed stream 110 in the hydrothermal reactor 112 can be between about 1 second to 120 minutes, optionally between about 5 seconds to 5 minutes, optionally between about 1 to 3 minutes, optionally between about 30 to 60 seconds, optionally between about 1 minutes to 60 minutes, optionally between about 2 minutes to 30 minutes, optionally between about 5 minutes to 15 minutes, or optionally between about 10 seconds to 10 minutes, where each range is inclusive. The residence time in the reactor is sufficient such that some contaminants are liberated from the feedstock
Hydrothermal reactor 112 produces a product stream 114 that is cooled in a heat exchanger 116, yielding a cooled product stream 118, which then passes through a pressure control valve or backpressure regulator 120 that maintains system pressure. Depressurized product stream 122 is further cooled as necessary, for examples by a further cooling heat exchanger (not shown). The temperature of the partially cooled product stream 118 may be about 90° C. or less, such as a temperature of from 40° C. and 80° C. The cooled product stream 122 is then fed to a separator 124. Additional compounds maybe be added to separator 124 to facilitate or improve phase separation or phase boundary. Such separation aids are known in the art.
Treated or cleaned feedstock 126 and process water stream 128 are removed from the separator 124. It can be appreciated that following separation 124 the treated or cleaned feedstock 126 may be subjected to subsequent separations and purifications including of one or more vapor-liquid separation unit operations including single-stage flash, rectification, stripping, centrifuging, water washing or distillation where the configuration and operation are dependent on the feedstock and product cleanup requirements. Optionally, the treated or cleaned feedstock may be stored in a treated feedstock storage tank 130.
In an alternative embodiment, and referring to
The process 200 further includes directly injecting steam 208 into the pressurized feedstock 206. The steam 208 may be provided at a pressure of from 1 to 10 MPa, 3 to 10 MPa, 3 to 7 MPa, 5 to 10 MPa, or from 5 to 8 MPa, or alternatively, at about 6 MPa. The direct steam injection 208 accomplishes heat transfer to the pressurized feedstock 206 traveling through the pipeline and the formation of a combined feedstock and water stream 210. The pressurized feedstock 206 is heated upon contact with steam 208 that is directly injected into the pressurized feedstock 206. Upon injection, the steam mixes with the pressurized feedstock 206, which further results in condensation of the steam 208, which thus provides the water for forming the combined feedstock and water stream 210.
The mass ratio of steam 208 to feedstock 206 can be between about 0.1:10 and 10:0.1, optionally between about 0.1:5 and 5:0.1, optionally between about 0.1:1 and 0.4:1.
The ratio of water to feedstock in stream 210 depends on the steam injected and amount condensed. For example, if the desired water to feedstock ratio is 0.5, and the desired temperature after direct steam injection is 200° C.
The temperature of the heated feedstock and water stream 210 may be from 50 to 280° C., from 250 to 275° C., optionally between about 80 and 200° C., alternatively between about 90 and 180° C., or between about 100 and 150° C. Alternatively, the temperature of the heated and pressurized combined feedstock and water stream may be greater than or equal to 200° C. but less than or equal to 260° C., such as 200-260° C., 220-260° C., 230-260° C., 240-260° C., 210-250° C., or 220-250° C., inclusive.
The combined feedstock and water stream 210 may then be processed further as is described in detail with respect to
The hydrothermal feedstock treatment process operated as described above dissociates inorganic contaminants (e.g., salts, minerals, and/or metals) which partition into the process water stream 228 and greater than 95%, for example from 95% to 99% of the contaminants are eliminated from the contaminated feedstock 202.
In an alternative embodiment, and referring to
Optionally, the filtered feedstock 304b may be passed through a heat exchanger 322 allowing for heat exchange with a pre-cooled reactor effluent 320, which exists the heat exchanger 322 as product stream 324. Optionally, the filtered feedstock 304b may further be heated in a feed heater 305, thereby producing a heated feedstock 306. Heated feedstock 306 may be supplied to a deaerator 307a. Gases, such as for example air, oxygen and carbon dioxide, may exit the deaerator 307a as gas stream 307b. Optionally, gas stream 307b is supplied to a vacuum system, captured, stored or further processed.
A degassed feed stock stream 308a exits on the bottom the deaerator 307a. The degassed feed stock stream 308a may optionally be pressurized via pump 308b, recycled to the deaerator 307a, or further pressurized to forming a reactor supply stream 309c. Reactor supply stream 309c may be preheated in heat exchanger 316 forming a heated reactor supply stream 310 by exchanging heat with reactor effluent stream 314, which exists the heat exchanger 316 as a cooled reactor effluent 318.
Water is supplied to the process 300 by a water feed 350, optionally from storage in a water tank 352, and pumped through an RO water pump 354 forming water stream 355. Recycled water 356 may be returned to the water tank 352. The water stream 355 may be supplied to the process 300 via a water pump 360 as a pressurized water stream 362. Optionally, the pressurized water stream 362 may be preheated in heat exchanger 363 forming a heated water supply stream 364 by exchanging heat with cooled reactor effluent 318, which exists the heat exchanger 363 as a further cooled reactor effluent 320. The further cooled reactor effluent 320. The heated water supply stream 364 may further be heated by boiler feed heater 365 forming a heated boiler feed 366. The heated boiler feed 366 is supplied to steam generator 380, producing steam feed 382.
The process 300 further includes directly injecting steam feed 382 into heated reactor supply stream 310, forming reactor supply 311. The steam feed 382 may be provided at a pressure of from 1 to 10 MPa, 3 to 10 MPa, 3 to 7 MPa, 5 to 10 MPa, or from 5 to 8 MPa, or alternatively, at about 6 MPa. The direct steam injection 382 accomplishes heat transfer to the heated reactor supply stream 310 traveling through the pipeline and forming reactor supply 311. The reactor supply 310 is heated upon contact with steam 382 that is directly injected. Upon injection, the steam mixes with the heated reactor supply 310, which further results in condensation of the steam 382, which thus provides the water for forming the forming the reactor supply 311, which thus may also be referred to as a combined feedstock and water stream 311.
The mass ratio of steam 392 to feed stock in stream 311 can be between about 0.1:10 and 10:0.1, optionally between about 0.1:5 and 5:0.1, optionally between about 0.1:1 and 0.4:1.
The ratio of water to feedstock in stream 311 depends on the steam injected and amount condensed. For example, if the desired water to feedstock ratio is 0.5, and the desired temperature after direct steam injection is 200° C.
The temperature of the combined feedstock and water stream 311 may be from 50 to 280° C., from 250 to 275° C., optionally between about 80 and 200° C., alternatively between about 90 and 180° C., or between about 100 and 150° C.
The temperature of the cooled reactor effluent 318 may be about 90° C. or less, 80° C. or less, or a temperature of from 40° C. and 80° C.
The combined feedstock and water stream 311 is supplied to a hydrothermal reactor 312. The reaction temperature in the hydrothermal reactor 312 may be from 50 to 280° C., from 150 to 280° C., from 180 to 260° C. from 190 to 280° C. from 200 to 280° C., from 250 to 275° C., optionally between about 80 and 200° C., alternatively between about 90 and 180° C., or between about 100 and 150° C. The reaction temperature in the hydrothermal reactor 312 may exceed 250° C. For example, the reaction temperature may range from 250 to 280° C., 250 to 275° C., 250 to 270° C., 250 to 265° C., 250 to 260° C., or 250 to 255° C., where each range is inclusive.
The residence time of combined feedstock and water stream 311 in the hydrothermal reactor 312 can be between about 1 second to 120 minutes, optionally between about 5 seconds to 5 minutes, optionally between about 1 to 3 minutes, optionally between about 30 to 60 seconds, optionally between about 1 minutes to 60 minutes, optionally between about 2 minutes to 30 minutes, optionally between about 5 minutes to 15 minutes, or optionally between about 10 seconds to 10 minutes, where each range is inclusive. The residence time in the reactor is sufficient such that some contaminants are liberated from the feedstock
The combined feedstock and water stream 311 exhibits laminar flow within the hydrothermal reactor 312, for example at a Reynolds number of from 50 to 750, 75 to 1750, 100 to 1650, 250 to 1500, 500 to 2000, 750 to 2000, 1000 to 2000, 500 to 1000, 750 to 1250, 1250 to 1800, or 1500 to 2000, wherein each range is inclusive.
As noted, the reactor effluent stream 314 exits the hydrothermal reactor 312 and may optionally be cooled, as described above, via various heat exchangers. As cooling the product stream in this manner makes the process more economical, the heat exchangers may also be referred to as economizer. Optionally, the system may include a pressure control valve or backpressure regulator that maintains system pressure as necessary. Product stream 324 may be further cooled in product cooler 236 as necessary and cooled product stream 328 may be supplied to a separator 330. Treated or cleaned feedstock 334 and process water stream 332 are removed from the separator 330. It can be appreciated that following separation 330 the treated or cleaned feedstock 334 may be subjected to subsequent separations and purifications including of one or more vapor-liquid separation unit operations including single-stage flash, rectification, stripping, centrifuging, water washing or distillation where the configuration and operation are dependent on the feedstock and product cleanup requirements. Optionally, the treated or cleaned feedstock may be stored in a treated feedstock storage tank.
In an alternative embodiment, and referring to
In one embodiment, the process may also include providing water feed 404. A pump 405 may be provided for supplying water feed 404. In some embodiments the water feed 404 is heated to a temperature of greater than about 30° C., optionally between about 100 and 175° C., alternatively between about 50 and 75° C., or between about 20 and 50° C. In certain embodiments, water feed 404 is pressurized to a pressure of between about 1 and 10 MPa, alternatively to a pressure of between about 1 and 5 MPa.
The feedstock 402 and the water feed 404 are combined to form a combined feedstock and water stream 406. Feedstock 402 and water feed 404 can be combined by known means, such as for example, a valve, tee fitting or the like. The combined feedstock and water feed stream 406 is pressurized to a pressure of between about 1 to 10 MPa, 3 to 10 MPa, 3 to 6 MPa, 2 to 8 MPa, or alternatively to a pressure of between about 1 and 5 MPa. Optionally, feedstock 402 and water feed 404 can be combined in a larger holding vessel (not shown) that is maintained at a temperature of from between about 200 and 300° C. and pressure of between to 2 to 8 MPa. Optionally, the feedstock 402 and water feed 404 can be supplied to a larger vessel that includes mixing means, such as a mechanical stirrer, or the like. In certain embodiments, feedstock 402 and water feed 404 are thoroughly mixed at the point where they are combined. The mass ratio of feedstock 402 and water feed 404 can be between about 0:1 and 10:1, optionally between about 0:1 and 5:1, optionally between about 0:1 and 2:1, or optionally between about from 0:1 and 1:1.
The process further includes directly injecting steam 408 into the combined feedstock and water stream 406. The steam 408 may be provided at a pressure of from 1 to 10 MPa, 3 to 10 MPa, 3 to 7 MPa, 5 to 10 MPa, or from 5 to 8 MPa, or alternatively, at about 6 MPa. The direct steam injection 408 accomplishes heat transfer to the combined feedstock and water feed stream 406 traveling through the pipeline and forming the heated combined feedstock and water feed stream 410. The combined feedstock and water stream 406 is heated upon contact with steam 408 that is directly injected into the combined feedstock and water stream 406. Upon injection, the steam mixes with the combined feedstock and water stream 406. Further, the combined feedstock and water stream 406 is heated by the condensation of steam 408.
The mass ratio of steam 408 to combined feedstock and water feed 406 can be between about 0.1:10 and 10:0.1, optionally between about 0.1:5 and 5:0.1, optionally between about 0.1:1 and 0.4:1.
The ratio of water to feedstock in the combined feedstock and water 406 includes the steam injected and condensed and added by water feed 404.
The temperature of the heated and pressurized combined feedstock and water feed stream 410 may be from 50 to 280° C., optionally between about 80 and 200° C., alternatively between about 90 and 180° C., or between about 100 and 150° C. Alternatively, the temperature of the heated and pressurized combined feedstock and water feed stream may be greater than or equal to 200° C. but less than or equal to 260° C., such as 200-260° C., 220-260° C., 230-260° C., 240-260° C., 210-250° C., or 220-250° C., inclusive.
The heated combined feedstock and water feed stream 410 is supplied to a pipe 412 so dimensioned that the flow within the pipe is laminar. The laminar flow within the pipe may be characterized by a Reynolds number of less than about 2300, 2000, 1750, or 1500. In other examples, the laminar flow may have a Reynolds number of from 50 to 750, 75 to 1750, 100 to 1650, 250 to 1500, 500 to 2000, 750 to 2000, 1000 to 2000, 500 to 1000, 750 to 1250, 1250 to 1800, or 1500 to 2000, wherein each range is inclusive.
The pipe 412 can be made of stainless steel or a specialized corrosion-resistant material. The pipe 412 may further include an inert liner, such as an inert liner including polytetrafluoroethylene or polypropylene. One or more heating devices may be used to heat the incoming stream 410, such as for example, a strip heater, immersion heater, tubular furnace, electrical heat tracing cables, steam tracing, a fired heater, an electrical induction system, a hot oil or thermal fluid heating system, or the like, as known in the art, The incoming stream 410 may be heated to a temperature of from 200° C. and 370° C.
The temperature maintained in the pipe 412 can be between about 200 to 370° C., optionally between about 250 to 350° C., or optionally between about 220 to 250° C. The residence time of heated and pressurized combined feed stream 410 in the pipe 412 can be between about 1 second to 120 minutes, optionally between about 5 seconds to 5 minutes, optionally between about 1 to 3 minutes, optionally between about 30 to 60 seconds, optionally between about 1 minutes to 60 minutes, optionally between about 2 minutes to 30 minutes, optionally between about 5 minutes to 15 minutes, or optionally between about 10 seconds to 10 minutes, where each range is inclusive. The residence time in the reactor is sufficient such that some contaminants are liberated from the feedstock
The pipe 412 produces a product stream 414 that is cooled in a heat exchanger 416, yielding a cooled product stream 418, which then passes through a pressure control valve or backpressure regulator 420 that maintains system pressure. Depressurized product stream 422 is further cooled as necessary, for examples by a further cooling heat exchanger (not shown). The temperature of the partially cooled product stream 418 may be about 90° C. or less, a temperature of from 40° C. and 80° C. The cooled product stream 422 is then fed to a separator 424. Additional compounds maybe be added to separator 424 to facilitate or improve phase separation or phase boundary. Such separation aids are known in the art.
Treated or cleaned feedstock 426 and process water stream 428 are removed from the separator 424. It can be appreciated that following separation 424 the treated or cleaned feedstock 426 may be subjected to subsequent separations and purifications including of one or more vapor-liquid separation unit operations including single-stage flash, rectification, stripping, centrifuging, water washing or distillation where the configuration and operation are dependent on the feedstock and product cleanup requirements. Optionally, the treated or cleaned feedstock may be stored in a treated feedstock storage tank 430.
The exemplary reactor operating conditions provided in Table 1 can be used for the removal of metals from soybean oil.
In a process conducted according to the scheme in
The process removes contaminants, such as metal contaminants, from a reactor feedstock, reactor product oil, and centrifuged reactor product oil. Non-limiting examples of contaminants that can be dissociated from feedstock include but are not limited to phosphorous, magnesium, potassium, and calcium. Table 2 shows comparative levels of phosphorus, magnesium, potassium, and calcium removed from crude and water-degummed soybean oil at various stages of a treatment process. Parts per million (ppm) levels of trace metal contaminants was determined using Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES).
Although the present invention has been described in detail, it should be understood that various changes, substitutions, and alterations can be made without departing from the principle and scope of the invention.
The present application claims priority to U.S. Provisional Application No. 63/470,602, filed on Jun. 2, 2023, and entitled “HYDROTHERMAL FEEDSTOCK TREATMENT,” the entire disclosure of which is expressly incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| 63470602 | Jun 2023 | US |
