EP2861331A1

EP2861331A1 - Non-dispersive process for insoluble oil recovery from liquid sources

Info

Publication number: EP2861331A1
Application number: EP13803446.7A
Authority: EP
Inventors: Frank Seibert
Original assignee: University of Texas System; University of Texas at Austin
Current assignee: University of Texas System; University of Texas at Austin
Priority date: 2012-06-14
Filing date: 2013-06-14
Publication date: 2015-04-22
Also published as: WO2013188837A1; CA2874012C; EP2861331A4; MX2014014942A; CA2874012A1

Abstract

The present invention is directed to a method and system of recovering one or more oils from an aqueous mixture comprising using one or more non-dispersive hydrophobic hollow fiber membrane contactors, comprising the steps of pumping the aqueous mixture comprising the one or more oils to the one or more non-dispersive hydrophobic hollow fiber membrane contactors; and collecting a stream from the contactor, wherein the stream comprises the oils without the need for a counterflowing recovery fluid.

Description

NON-DISPERSIVE PROCESS FOR INSOLUBLE OIL RECOVERY FROM LIQUID SOURCES

TECHNICAL FIELD OF THE INVENTION

The present invention relates in general to the field of insoluble oil recovery from liquid sources, and more particularly, to a microporous membrane based method for recovering oil from liquid sources. BACKGROUND OF THE INVENTION

Without limiting the scope of the invention, its background is described in connection with recovery methods for insoluble and low solubility compounds having economic value from liquid sources that may include one or more types of biological cells, cellular debris or other matter physically small enough to enter the membrane.

U.S. Pat. No. 4,439,629 issued March 27, 1984 to Ruegg describes a process for extracting either or both beta-carotene or glycerine from algae containing these substances, especially from algae of the genera Dunaliella. According to the Ruegg patent either or both of beta-carotene or glycerine can be extracted from algae. If it is desired to extract beta-carotene, the algae are first treated with calcium hydroxide and then filtered. The residue from this filtration is treated with a beta-carotene solvent, which removes the beta-carotene from the residue and into the solvent. The beta-carotene can be recovered from the solvent by conventional means. If it is desired to extract glycerine, the filtrate from the treatment of the algae with calcium hydroxide is neutralized, concentrated and the residue from the solid is treated with a lower alkanol to remove glycerine from the residue.

U.S. Pat. No. 5,378,369 issued Jan. 3, 1995 to Rose et al. discloses a method for the solvent- extraction of β-carotene from an aqueous algal biomass suspension, whereby a vegetable oil which is immiscible with water is mixed with an aqueous biomass suspension, the biomass containing the β- carotene, to form a mixture of the organic phase and the aqueous suspension, whereby the β-carotene is caused to dissolve in the organic phase. This is followed by separation of the organic phase from the aqueous phase by passing the organic phase containing the dissolved β-carotene through a semi- permeable membrane to effect microfiltration or ultrafiltration of the organic phase. The membrane is of a material that is hydrophobic and the organic phase is passed through the membrane with a pressure drop across the membrane which is lower than that which causes the aqueous phase to pass through the membrane.

SUMMARY OF THE INVENTION

In one embodiment the present invention includes a method of recovering one or more oils from a liquid source using one or more membrane or membrane contactors, comprising the steps of: pumping the aqueous mixture comprising the one or more oils into contact with a first surface of the one or more membranes or membrane contactors; coalescing the one or more oils from the aqueous mixture onto the first surface of the one or more membrane or membrane contactors; and collecting a stream of coalesced oil from the second surface of the one or more membrane or membrane contactors, wherein the stream comprises the oils without the need for a counterflowing recovery fluid. In one aspect, the aqueous mixture is selected from at least one of oily water, oil industry waste streams, oil contaminated water or brine, wastewater, contaminated oil, oil containing drainage water, water contaminated with oil, seawater contaminated with oil, brine contaminated with oil, industrial effluents that comprise oil, natural effluents that comprise oil, drilling mud, tailing ponds, leach residue, produced water, oil sands tailing, frac water, connate water, an oil/water/solid mixture, a gravity separated oil/water/solid mixture, water-oil mixtures, aqueous slurries, aqueous slurries comprising broken cells, live cells or organisms, biocellular mixtures, lysed cellular preparations, or lipophobic contaminants that have not been separated or have been separated by at least one of gravity, centrifugal, centripedal, or hydrocyclone separation. In another aspect, the aqueous mixture is processed by the method within 1, 2, 4, 6, 8, 12, 24, 26, 48 or 72 hours from production. In another aspect, the aqueous mixture contains one or more organisms that include at least one of intact cells, lysed cells, apoptotic cells, necrotic cells, wherein organisms comprises two or more different organisms, wherein organism is a yeast, algae or bacteria, or wherein the organism is capable of secreting oil or causing the accumulation of oil outside living cells. In another aspect, the aqueous mixture contains one or more organisms that are genetically modified to render them capable of secreting hydrophobic components, organisms that are capable of causing accumulation of the one or more hydrophobic components outside living cells, organisms that are capable of causing accumulation of the one or more hydrophobic components outside living cells upon induction with one or more chemical probes, exogenous agents, or pharmaceuticals, or combinations thereof.

In another aspect, the method further comprises contacting the organism with chemical probes, exogenous agents, or pharmaceuticals, whereby the metabolism of the one or more organism is modified, wherein at least one organism causes accumulation of the one or more oils outside living cells. In another aspect, the method further comprises the step of contacting the one or more oils in the liquid source to remove oil, then returning the aqueous mixture to a growth environment. In another aspect, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%, 99% or 100% of the one or more insoluble oils in the liquid source are recovered. In another aspect, the source of the aqueous mixture is a growth environment for algae, bacteria or yeast and the insoluble oils are recovered the using one or more membrane or membrane contactors comprising the steps of: contacting the growth media comprising organisms and insoluble oils with a first surface in the one or more membrane or membrane contactors; removing a first stream from the contactor or the vessel, wherein the first stream comprises the growth media and organisms, wherein the organisms can continue to produce the insoluble oils; and removing a second stream from the second surface of one or more membrane or membrane contactors, wherein the second stream comprises the one or more insoluble oils without the need for a recovery fluid. In another aspect, the method further comprises feeding or pumping the first stream to the growth environment to resume oil production by the organisms. In another aspect, the one or more membrane or membrane contactors are selected from at least one of polyethylene, polypropylene, polyolefins, polyvinyl chloride (PVC), amorphous Polyethylene terephthalate (PET), polyolefin copolymers, poly(etheretherketone) type polymers, surface modified polymers, or surface modified polymers comprise polymers modified chemically at one or more halogen groups by corona discharge or by ion embedding techniques.

In another embodiment the present invention includes a system for recovering one or more oils from an aqueous mixture comprising using one or more non-dispersive membrane or membrane contactors, comprising the steps of: a source of a stream comprising an aqueous mixture containing oil; a pump that circulates the aqueous mixture comprising the one or more oils to a first surface of the one or more membrane or membrane contactors, wherein the one or more oils coalesce at the first surface of the one or more membrane or membrane contactors; and a collection conduit or vessel for a stream from a second surface of the one or more membrane or membrane contactors, wherein the stream comprises the oils without the need for a counterflowing recovery fluid. In another aspect, the aqueous mixture contains one or more organisms that include at least one of intact cells, lysed cells, apoptotic cells, or necrotic cells, comprises two or more different organisms, comprise yeast, algae or bacteria or comprise organisms capable of secreting oil or causing the accumulation of oil outside living cells. In another aspect, the aqueous mixture contains one or more organisms that are genetically modified to render them capable of secreting hydrophobic components, organisms that are capable of causing accumulation of the one or more hydrophobic components outside living cells, organisms that are capable of causing accumulation of the one or more hydrophobic components outside living cells upon induction with one or more chemical probes, exogenous agents, or pharmaceuticals, or combinations thereof. In another aspect, the method further comprises contacting the organism with chemical probes, exogenous agents, or pharmaceuticals, whereby the metabolism of the one or more organism is modified, wherein at least one organism causes accumulation of the one or more oils outside living cells. In another aspect, the method further comprises the step of contacting the one or more oils in the liquid source to remove oil, then returning the aqueous mixture to a growth environment. In another aspect, 45%, 50%, 55%o, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%, 99% or 100% of the one or more insoluble oils in the liquid source are recovered. In another aspect, the one or more membrane or membrane contactors area selected from at least one of polyethylene, polypropylene, polyolefins, polyvinyl chloride (PVC), amorphous Polyethylene terephthalate (PET), polyolefin copolymers, poly(etheretherketone) type polymers, surface modified polymers, or surface modified polymers modified chemically at one or more halogen groups by corona discharge or by ion embedding techniques. In another aspect, once the system is collecting oil, further comprising the step of counterflowing a recovery fluid that comprises the same oil recovered in the initial operation of the contactor. BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the features and advantages of the present invention, reference is now made to the detailed description of the invention along with the accompanying figures and in which:

FIG. 1 is a schematic showing the method and the oil recovery principle in which a recovery fluid is used;

FIG. 2A is a flow diagram of the novel oil coalescence process of the present invention that does not require the use of a counterflowing recovery fluid;

FIG. 2B is a flow diagram of yet another novel oil simplified coalescence process (without the need for a counterflowing oil or fluid) of the present invention;

FIGS. 2C and 2D are graphs that show the recovery rates for the recovery process of Fig. 2B, in which no counterflowing oil or fluid was used;

FIG. 3 is a graph that compares the recovery of oil from a mixture created with -12% oil in water mixture; and

FIG. 4 is a graph that compares is running 3 gpm of oil (isopar V) on the shell side with the shell side outlet open.

DETAILED DESCRIPTION OF THE INVENTION

While the making and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention and do not delimit the scope of the invention.

To facilitate the understanding of this invention, a number of terms are defined below. Terms defined herein have meanings as commonly understood by a person of ordinary skill in the areas relevant to the present invention. Terms such as "a", "an" and "the" are not intended to refer to only a singular entity, but include the general class of which a specific example may be used for illustration. The terminology herein is used to describe specific embodiments of the invention, but their usage does not delimit the invention, except as outlined in the claims.

As used herein, the terms "liquid" or "liquid source," encompasses liquids containing any of the following in any combination; insoluble oils (hydrocarbons and hydrocarbon-rich molecules of commercial value) that are produced by oil fields, or products from oil fields, including mixed oil-water streams. The terms "aqueous slurry" or "aqueous mixture" are a subset of the liquid or liquid sources that are water based an containing any of the following in any combination; insoluble oils (hydrocarbons and hydrocarbon-rich molecules of commercial value) that are produced by oil fields, or products from oil fields, including mixed oil-water streams. For newly produced hydrocarbons the present invention may be used with living, dead, damaged and/or broken cells (or not), proteins and other cellular debris, including sugars, DNA, RNA, etc., or other matter physically small enough to enter the membrane. The slurry may also contain a solvent that was used to pre-treat cells to liberate compounds of interest. In certain applications it is possible to process a "slurry" that contains solids small enough to enter the contactor, e.g., solids that are not physically too large to pass into the contactor (for example, approx. 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 500 microns or larger).

The term "oil" as used herein refers to a single hydrocarbon or hydrocarbon-rich molecule including a complex mixture of lipids, hydrocarbons, free fatty acids, triglycerides, aldehydes, etc. The term oil also includes, e.g., C₈ (jet fuel compatible), C₆o (motor oil compatible) and oils that are odd- or even-chain oils (and mixtures thereof), e.g., from Οβ to C120. Oil also comprises hydrophobic or lipophilic compounds.

The term "pumping" comprises all methods of pumping, propelling, or feeding fluid from one location to another employing hoses, lines, tubes ducts, pipes, or pipelines including under pressure. It also includes gravity flow of fluid.

In another embodiment, the present invention describes a method of recovering one or more hydrocarbons or hydrocarbon-rich molecules (e.g., farnesene, squalane, aldehydes, triglycerides, diglycerides, etc.) or combinations thereof, from an aqueous preparation using one or more hydrophobic membranes or membrane modules. Without limiting the scope of the invention, an example includes recovery of hydrocarbon and hydrocarbon-rich molecules produced by microbial fermentation. Microbial fermentation processes are described in which organisms including algae, yeast, E. coli, fungi, etc. are used to metabolize carbon sources (e.g., sugars, sugarcane bagasse, glycerol, etc.) into hydrocarbons and hydrocarbon-rich molecules that are secreted from (or accumulate within) the cells. Such organisms are expected, by design, to produce physically small oil droplets the process described herein will be immediately applicable to recover insoluble oils produced by microbial platforms. The oil wastes may include but are not limited to, e.g., oil industry liquid streams, oil contaminated water or brine, drilling mud, produced water, and oil sands tailings, to name a few. The oil wastes can be pre- processed by, e.g., gravity separation or separated by other methods, e.g., filtration, centrifugation and the like.

In addition to the steps listed herein above the method of the present invention further involves the steps of collecting the one or more coalesced lipid components, oils or both in a collection vessel. In one embodiment of the present invention, the system is initiated without a recovery fluid to begin the recovery of the unique oil from the aqueous slurry and once a volume of oil has been recovered from the slurry, a recovery fluid system be added or inititated (if already present but not operational) in which one or more hydrophobic liquids, or the oil recovered through the initial operation, are used as the recovery fluids. In one aspect the hydrophobic membrane or membrane module comprises microporous hollow fiber membranes, selected from polyethylene, polypropylene, polyolefms, polyvinyl chloride (PVC), amorphous Polyethylene terephthalate (PET), polyolefin copolymers, poly(etheretherketone) type polymers, surface modified polymers, mixtures or combinations thereof. The surface modified polymers comprise polymers modified chemically at one or more halogen groups or by corona discharge or by ion embedding techniques. In one aspect the counterflowing fluid is oil. In yet another aspect of the method of the present invention the one or more counterflowing fluids comprise hydrophobic liquids, alkanes such as hexane, aromatic solvents such as benzene, toluene, ethers such as diethyl ether, halogenated solvents such as chloroform, dichloromethane, and esters such as ethyl acetate, or mixtures thereof.

The present invention also provides for a method of coalescing one or more oils from an liquid source or aqueous slurry using one or more hydrophobic membranes or membrane modules. The one or more oils in the aqueous stream coalesce on the surface of the membrane or the membrane module. The coalesced oil accumulates within the tube volume and flows out of the module.

The present invention also describes a method for recovering oil from oil from water and/or solid mixtures using hydrophobic microporous hollow fiber membrane. The system can also include, but does not require a recovery fluid, which can be a hydrophobic liquid, a biodiesel, an oil or mixtures thereof. The use of a solid removal system and a hydrophobic microporous hollow fiber membrane provides a non-dispersive method of coalescing and recovering the oil without the need of gravity separation.

In one aspect of the method of the present invention the one or more natural fatty acids are designated as [X]:[Y], wherein X represents the number of carbon atoms in the one or more fatty acids ranging from 8-22 and Y represents one or more double bonds in the fatty acids ranging from 0-6. In another aspect the one or more natural fatty acids or salts thereof comprise Myristoleic acid, Palmitoleic acid, Sapienic acid, Oleic acid, Linoleic acid, a-Linolenic acid, Arachidonic acid, Eicosapentaenoic acid, Erucic acid, Docosahexaenoic acid, Laurie acid, Myristic acid, Palmitic acid, Stearic acid, Arachidic acid, and combinations thereof. In yet another aspect the lysed algal preparation comprises a concentrate, a slurry, a suspension, a dispersion, an emulsion, a solution or any combinations thereof.

In a related aspect the hydrophobic membrane or membrane module comprises microporous hollow fiber membranes, selected from polyethylene, polypropylene, polyolefms, polyvinyl chloride (PVC), amorphous Polyethylene terephthalate (PET), polyolefin copolymers, poly(etheretherketone) type polymers, surface modified polymers, mixtures or combinations thereof. The surface modified polymers comprise polymers modified chemically at one or more halogen groups or by corona discharge or ion embedding techniques.

In another embodiment the instant invention describes a contactor or vessel for recovering one or more insoluble oil components from the bio-cellular aqueous slurry such as but not limited to oil industry waste streams, oil contaminated water or brine, wastewater, industrial or natural effluents, drilling mud, produced water, oil sands tailing, an oil/water/solid mixture that has been gravity separated, water-oil mixtures, aqueous slurries, algal oils or both from live, whole cells, cells debris, oil waste, lysed or unlysed cellular concentrates. The contactor or vessel as described herein comprises, an external polypropylene or other polymeric casing, one or more microporous hollow fiber membrane cartridges comprising a plurality of microporous hollow fiber membranes enclosed by the metal casing, wherein the one or more membrane cartridges divide the casing into a shell-side and a fiber side, one or more baffles on the shell-side of the metal casing, one or more distribution tubes on the fiber-side of the metal casing, two inlet ports connected to the external metal casing, wherein the lysed algal concentrate is pumped to the shell-side through the first inlet port and a strip gas or a solvent is fed to the fiber side through the second inlet port, and two outlet ports connected to the metal casing, wherein the an algal raffinate comprising the algal biomass is removed from the first outlet port and a solvent/recovered lipid or oil mixture or the strip gas is removed from the second outlet port.

In one aspect the microporous hollow fiber membrane comprises polyethylene, polypropylene, polyolefins, polyvinyl chloride (PVC), amorphous Polyethylene terephthalate (PET), polyolefin copolymers, poly(etheretherketone) type polymers, surface modified polymers, mixtures or combinations thereof. The surface modified polymers comprise polymers modified chemically at one or more halogen groups or by corona discharge or ion embedding techniques.

In yet another aspect 45-80% of the one or more algal oils in the lysed algal concentrate are recovered by the method of the present invention. As per the method described in the present invention 45%o, 55%o, 60%>, 65%>, 70%o, 75%o, and 80%> of the one or more algal oils in the lysed algal concentrate are recovered.

In one aspect of the method discloses hereinabove the biocellualr mixture comprises algae, protists, fungi, yeast, E. coli, mixed cultures of cells, and combinations thereof. In another easpect the method recovers 45-100% of the one or more insoluble oils in the liquid source. In yet another aspect 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%, 99% and 100% of the one or more insoluble oils in the liquid source are recovered.

FIG. 1 shows an oil recovery unit 100 that uses a typical recovery fluid. The unit 100 comprises a housing 102, within which is contained a membrane module 104 comprising a plurality of microporous hollow fiber membrane units depicted as 104a, 104b, and 104c. The unit has two inlet ports 106 and 108. The aqueous slurry is fed (pumped) through port 106. A recovery fluid is pumped through inlet port 108. The recovery fluid can be a hydrophobic liquid, a biodiesel, an oil or mixtures thereof. The aqueous slurry counterflows with the recovery fluid flowing inside the microporous hollow fiber membranes 104a, 104b, and 104c. The oils or lipid in the aqueous stream coalesce on the surface of the hollow fiber membranes and are swept by and recovered by the recovery fluid and exit the unit 100 through the outlet port 110. The exit stream is taken for further processing if necessary. The recovery fluid containing newly recovered oil flows out of the unit 100 through port 112.

A wide variety of organisms can be used to generate oils and lipids that can be recovered with the present invention. Non-limiting examples of algae and microalgae may be grown and used with the present invention including one or more members of the following divisions: Chlorophyta, Cyanophyta (Cyanobacteria), and Heterokontophyt. Non-limiting examples of classes of microalgae that may be used with the present invention include: Bacillariophyceae, Eustigmatophyceae, and Chrysophyceae. Non- limiting examples of genera of microalgae used with the methods of the invention include: Nannochloropsis, Chlorella, Dunaliella, Scenedesmus, Selenastrum, Oscillatoria, Phormidium, Amphora, and Ochromonas. Non-limiting examples of microalgae species that can be used with the present invention include: Achnanthes orientalis, Agmenellum spp., Amphiprora hyaline, Amphora coffeiformis, Amphora coffeiformis var. linea, Amphora coffeiformis var. punctata, Amphora coffeiformis var. taylori, Amphora coffeiformis var. tenuis, Amphora delicatissima, Amphora delicatissima var. capitata, Amphora sp., Anabaena, Ankistrodesmus, Ankistrodesmus falcatus, Boekelovia hooglandii, Borodinella sp., Botryococcus braunii, Botryococcus sudeticus, Bracteococcus minor, Bracteococcus medionucleatus, Carteria, Chaetoceros gracilis, Chaetoceros muelleri, Chaetoceros muelleri var. subsalsum, Chaetoceros sp., Chlamydomas perigranulata, Chlorella anitrata, Chlorella antarctica, Chlorella aureoviridis, Chlorella Candida, Chlorella capsulate, Chlorella desiccate, Chlorella ellipsoidea, Chlorella emersonii, Chlorella fusca, Chlorella fusca var. vacuolata, Chlorella glucotropha, Chlorella infusionum, Chlorella infusionum var. actophila, Chlorella infusionum var. auxenophila, Chlorella kessleri, Chlorella lobophora, Chlorella luteoviridis, Chlorella luteoviridis var. aureoviridis, Chlorella luteoviridis var. lutescens, Chlorella miniata, Chlorella minutissima, Chlorella mutabilis, Chlorella nocturna, Chlorella ovalis, Chlorella parva, Chlorella photophila, Chlorella pringsheimii, Chlorella protothecoides, Chlorella protothecoides var. acidicola, Chlorella regularis, Chlorella regularis var. minima, Chlorella regularis var. umbricata, Chlorella reisiglii, Chlorella saccharophila, Chlorella saccharophila var. ellipsoidea, Chlorella salina, Chlorella simplex, Chlorella sorokiniana, Chlorella sp., Chlorella sphaerica, Chlorella stigmatophora, Chlorella vanniellii, Chlorella vulgaris, Chlorella vulgaris fo. tertia, Chlorella vulgaris var. autotrophica, Chlorella vulgaris var. viridis, Chlorella vulgaris var. vulgaris, Chlorella vulgaris var. vulgaris fo. tertia, Chlorella vulgaris var. vulgaris fo. viridis, Chlorella xanthella, Chlorella zofingiensis, Chlorella trebouxioides, Chlorella vulgaris, Chlorococcum infusionum, Chlorococcum sp., Chlorogonium, Chroomonas sp., Chrysosphaera sp., Cricosphaera sp., Crypthecodinium cohnii, Cryptomonas sp., Cyclotella cryptica, Cyclotella meneghiniana, Cyclotella sp., Dunaliella sp., Dunaliella bardawil, Dunaliella bioculata, Dunaliella granulate, Dunaliella maritime, Dunaliella minuta, Dunaliella parva, Dunaliella peircei, Dunaliella primolecta, Dunaliella salina, Dunaliella terricola, Dunaliella tertiolecta, Dunaliella viridis, Dunaliella tertiolecta, Eremosphaera viridis, Eremosphaera sp., Effipsoidon sp., Euglena spp., Franceia sp., Fragilaria crotonensis, Fragilaria sp., Gleocapsa sp., Gloeothamnion sp., Haematococcus pluvialis, Hymenomonas sp., Isochrysis off galbana, Isochrysis galbana, Lepocinclis, Micractinium, Micractinium, Monoraphidium minutum, Monoraphidium sp., Nannochloris sp., Nannochloropsis salina, Nannochloropsis sp., Navicula acceptata, Navicula biskanterae, Navicula pseudotenelloides, Navicula pelliculosa, Navicula saprophila, Navicula sp., Nephrochloris sp., Nephroselmis sp., Nitschia communis, Nitzschia alexandrina, Nitzschia closterium, Nitzschia communis, Nitzschia dissipata, Nitzschia frustulum, Nitzschia hantzschiana, Nitzschia inconspicua, Nitzschia intermedia, Nitzschia microcephala, Nitzschia pusilla, Nitzschia pusilla elliptica, Nitzschia pusilla monoensis, Nitzschia quadrangular, Nitzschia sp., Ochromonas sp., Oocystis parva, Oocystis pusilla, Oocystis sp., Oscillatoria limnetica, Oscillatoria sp., Oscillatoria subbrevis, Parachlorella kessleri, Pascheria acidophila, Pavlova sp., Phaeodactylum tricomutum, Phagus, Phormidium, Platymonas sp., Pleurochrysis carterae, Pleurochrysis dentate, Pleurochrysis sp., Prototheca wickerhamii, Prototheca stagnora, Prototheca portoricensis, Prototheca moriformis, Prototheca zopfii, Pseudochlorella aquatica, Pyramimonas sp., Pyrobotrys, Rhodococcus opacus, Sarcinoid chrysophyte, Scenedesmus armatus, Schizochytrium, Spirogyra, Spirulina platensis, Stichococcus sp., Synechococcus sp., Synechocystisf, Tagetes erecta, Tagetes patula, Tetraedron, Tetraselmis sp., Tetraselmis suecica, Thalassiosira weissflogii, and Viridiella fridericiana.

Other sources for biomass can be a wild type or genetically modified fungus. Non-limiting examples of fungi that may be used with the present invention include: Mortierella, Mortierrla vinacea, Mortierella alpine, Pythium debaryanum, Mucor circinelloides, Aspergillus ochraceus, Aspergillus terreus, Penicillium iilacinum, Hensenulo, Chaetomium, Cladosporium, Malbranchea, Rhizopus, and Pythium. As the source of biomass is not limited using the devices and methods of the present invention can be wild type or genetically modified yeast. Non-limiting examples of yeast that can be used with the present invention include Cryptococcus curvatus, Cryptococcus terricolus, Lipomyces starkeyi, Lipomyces lipofer, Endomycopsis vernalis, Rhodotorula glutinis, Rhodotorula gracilis, Candida 107, Saccharomyces paradoxus, Saccharomyces mikatae, Saccharomyces bayanus, Saccharomyces cerevisiae, any Cryptococcus, C. neoformans, C. bogoriensis, Yarrowia lipolytica, Apiotrichum curvatum, T. bombicola, T. apicola, T. petrophilum, C. tropicalis, C. lipolytica, and Candida sp., e.g., Candida albicans.

The aqueous slurry may consist of bacteria that generate lipids, oils, proteins, and carbohydrates, whether naturally or by genetic engineering. Non-limiting examples of bacteria that can be used with the present invention include Escherichia coli, Acinetobacter sp. any actinomycete, Mycobacterium tuberculosis, any streptomycete, Acinetobacter calcoaceticus, P. aeruginosa, Pseudomonas sp., R. erythropolis, N. erthopolis, Mycobacterium sp., B., U. zeae, U. maydis, B. lichenformis, S. marcescens, P. fluorescens, B. subtilis, B. brevis, B. polmyma, C. lepus, N. erthropolis, T. thiooxidans, D. polymorphis, P. aeruginosa and Rhodococcus opacus.

The present invention focuses on the "wet" process and the novel non-dispersive contactor used to coalesce and recover the desirable non-polar lipids or oils directly from the aqueous slurry.

FIG. 2A is a schematic 600 depicting a novel oil recovery process (without hydrophobic liquid, using a hydrophobic liquid) of the present invention. The process comprises a MHF contactor 602 comprising a plurality of microporous hollow fiber membranes 604 and a central baffle 606. In one non- limiting example of an oil, non-polar Algae oil 608 is fed (pumped) through the membrane fibers 604 and is contacted with the lysed yeast or algal oil concentrate 612 contained in the shell portion of the MHF contactor 602. The non -polar Algae oil functions to dissolved and sweep the coalesced oil from the Algae concentrate. The non -polar oil 616 coalesces onto the hydrophobic fiber surface 604 and dissolves into oil contained in the walls and the counterflowing oil phase 608 and can be removed. There are two exit streams from the contactor 602, a yeast or algal biomass stream 610 which is processed further a stream 608a which contains the yeast or algal oils and lipids 616 that is collected in a tank 614. Part of the oil 616 can be removed from the tank 614 and fed to the contactor 602 to repeat the process. Media, nutrients, additional organisms (yeast or algal), liquid or other compositions can be provided from burettes 619. Multiple pumps and valves may be used to control the flow of the various liquids and components.

FIG. 2B is a schematic 600 depicting another novel oil recovery process of the present invention. The process comprises a MHF contactor 602 comprising a plurality of microporous hollow fiber membranes 604 and a central baffle 606. Oily feed 612 is pumped through the shell side of the MHF contactor 602. The non -polar oil 616 coalesces onto the hydrophobic fiber surface 604 and accumulates in the tube side of the module and flows 608 to a collection tank 614. There are two exit streams from the contactor 602, a shell side stream 610 which has oil removed and 608 which contains the removed oils and lipids 616 that is collected in a tank 614. A source of additional liquid 619, such as from a burette, can also be provided. FIGS. 2C and 2D are graphs that show the recovery rates for the recovery process of Figs. 2A and 2B, in which no counterflowing oil was used.

While the present inventors have described an oil recovery system in US Patent Publication No. 2011-0174734-Al, the present inventors have developed a novel method for obtaining samples and separation of oils that does not require a counterflowing recovery fluid. The novel method and system has the advantage of reducing the number of components in the system, it allows for rapid collection in the field of samples and separated oil. The nature of the aqueous fluid that is the source of the oil only requires that it be pumpable and be suspected of having an oil, without regard to the source of oils, which can be from an aqueous solution that includes oils (e.g., extraction from underground formations), oils extracted from plants, algae, bacteria, archaebacteria, or other organisms, and combinations thereof.

The MHF contactor provides: (i) high contact area for coalescence and mass transfer, (ii) processing of un-flocculated or deflocculated solids in aqueous slurries, (iii) large flow capacities on the shell side, (iv) negligible mass transfer resistance in the pore because of the high equilibrium distribution coefficient of non-polar oils into non-polar recovery fluid, and (v) low cost per unit area as the contact area is 100X that for the conventional liquid extraction contactor, (e.g. perforated plate column).

The following is an example of set up for oil recovery using no recovery fluid. Skid set up: 4 inch, X50 membrane (previously used, cleaned, dried, and quality controlled); No recovery oil and no oil recirculation; Shell side: 2 gpm flow, 30 psi; Oil injected: 800ml/min. Briefly, the skid was set up set-up to have water run and continuously recirculate on shell side at the rates stated above. 5 gallons of water were used on the shell side. Oil was continuously injected before the shell side feed pump to create an oil-in-water emulsion. Oil and water passed through the membrane. Oil coalesced out of the aqueous stream and passed to the tube side. The oil/water emulsion, now containing less oil, recirculated back to the shell side feed tank and was mixed with the volume already in the tank. Oil that passed through to the tube side flowed out of the system and was collected and measured into a graduated cylinder. Oil recovered was measured over time to determine a dynamic oil removal rate. The rate of oil flowing from the membrane was slow at first and, when applicable, accelerated until a steady state condition was reached. The total oil volume injected, in this small-scale set-up, was typically 24L. However, the skilled artisan will recognize that large batch and/or continuous flow system can be developed that take advantage of the present invention.

It should be noted that the aqueous slurry must not contain large solids, only small solids to prevent plugging within the membrane module. For the case of the MHF contactor described in the present invention, the minimum dimension for shell-side flow is 39 microns which greater than the size of most single alga.

These studies also support recovery of different hydrophobic or oil-soluble products (i.e., TAG); removal of oil from higher stability emulsions with smaller oil droplets; and that the technique can be applied to e.g., yeast biocatalyst platforms making drop-in hydrocarbon molecules. These hydrocarbons could be isolated with an efficiency of 90, 91, 92, 93, 94, 85, 96, 97, 98, and 99 % efficiency using the present invention.

One embodiment of the system includes coupling of the non-dispersive membrane contactor to growth environments in a closed loop fashion. The non-dispersive membrane contactor can be operated as a flow-through device, continuously collecting oil from aqueous slurries passing through the module. The inventors recognize that certain growth environments, such as fermenters or photobioreactors or pond are ideally operated in a clean fashion to minimize contamination and growth of unwanted organisms. The membrane contactor can be operated in conjunction with growth environments requiring clean operating conditions by connecting the in-flow and out- flow valves of the contactor with the growth chamber (via piping). Operated in this fashion, the growth media could circulate through the membrane contactor and emerge de-oiled and uncontaminated from the out-flow valve, allowing both the cells and growth media to be re-circulated into the growing environment, while the oil is collected in the module.

The oil recovery module is an extension of the growth environment, and the flow rate may be measured in liters or gallons per minute. The residence time in the module is very short, so the oil recovery step only has minimal effect on the viability of the cells or the temperature of the media. This mode of operation drastically increases the cost efficiency of the bio-hydrocarbon production by enabling continuous growth and continuous oil recovery and minimizing reactor downtime. Constantly removing the accumulating hydrocarbon may prompt the synthesis of additional hydrocarbon (by removing end- product inhibition, for example), depending on how the underlying metabolic pathways are regulated (Le Chatlier's principle).

One advantage of the present invention is the development of a non-lethal recovery system, which further reduces operating expenses for biohydrocarbon production by increasing yields per cell. It also increases operating efficiency by recovering oil in relatively smaller, continuous and predictable quantities. It may decrease expenses by enabling longer runs with less operational hours spent on cleaning and re-starting cultures. For photosynthetic organisms, the presence of oil in the growth media or adhering to cells may obscure light, reducing the efficiency of photosynthesis; active removal of this oil would be expected to increase the net photosynthesis.

It will be understood by the skilled artisan that the process described hereinabove is applicable broadly for insoluble oil recovery beyond yeast, E. coli, etc., mixed cultures of cells, grown by any method (not limited to photosynthetic organisms), aqueous slurries containing broken and/or live cells or no cells (in case pre -treated to remove cells/cell debris or other suspended materials). The process can also be used to recover oil from any liquid source comprising insoluble oils for e.g. industrial water, brine, wastewater, industrial or natural effluents, water-oil mixtures, aqueous slurries, aqueous slurries comprising broken cells, live cells or combinations thereof, bio-cellular mixtures, lysed cellular preparations, and combinations thereof. The process of the present invention is capable of recovering almost up to a 100% of the one or more insoluble oils in the liquid source. The process provides insoluble oil recoveries of 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%, 99% and 100%o from the liquid source.

The same methods and systems can be used to process oil field products. For example, a process for drilling mud may include: (1) course filtration to remove large particles (grass, gravel, sand etc.); (2) dilute with water (optional); (3) centrifuge to remove majority of remaining solids; (4) filtration to remove solids greater than 10, 20, 30 or 40 microns; and (5) feed the aqueous slurry on shell side of microporous hollow fiber membrane to recover oil on tube side.

The skilled artisan will recognize that some streams will either have no solids or solids that already meet the size selection criteria for processing (less than 10, 20, 30, 40 or 50 microns), so they may not need any pre-processing. If it is the case that some of the solids will stick to the membrane and cause a clog, a cleaning processes is used to remove the solids from the membrane to continue use. The present invention may also include a clog detector that determines if the membrane contactor system has become at least partially or fully clogged. Whether or not a clog is detected (e.g., if a clog detector is not used and rather a regular or sporadic cycle or maintenance is used), the invention may also include a system or method for cleaning the membrane contactor, e.g., physical-mechanical cleaning, use of chemicals, backflow, pressurized water, brine or other hydrophobic liquids or other methods for removing debris from the membrane contactor system. Thus, the present invention may also include one or more systems for cleaning, flushing and regenerating the membrane. Figure 3 compares the recovery of oil from an experimental created -12% oil in water mixture. 1000 mL of oil was injected into a water stream flowing at 2 gpm. Volumes of oil recovered were determined using a calibrated sight glass when recovery fluid was used, and by direct measurement of volume recovered from the tube side outflow when recovery fluid was not used. With recovery fluid, the instantaneous recovery is higher in the first minutes of operation.

Figure 4 shows the results from running 3 gpm of oil (isopar V) on the shell side with the shell side outlet open. Volumes of oil recovered were determined using a calibrated sight glass when recovery fluid was used, and by direct measurement of volume recovered from the tube side outflow when recovery fluid was not used. This study also shows the approximately linear relationship between pressure and flux, in which the flux rate increases with increasing pressure.

In certain examples, the streams may have been partially or completely gravity settled and/or may be predominantly oil with solids and comparatively small amounts of water. To separate the solids from the oil it may be necessary to apply pressure to the stream as it enters the solid removal system and/or the stream may have to be heated (in one example, steam is applied to the stream to both heat the stream and increase the water content).

It is contemplated that any embodiment discussed in this specification can be implemented with respect to any method, kit, reagent, or composition of the invention, and vice versa. Furthermore, compositions of the invention can be used to achieve methods of the invention.

It will be understood that particular embodiments described herein are shown by way of illustration and not as limitations of the invention. The principal features of this invention can be employed in various embodiments without departing from the scope of the invention. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, numerous equivalents to the specific procedures described herein. Such equivalents are considered to be within the scope of this invention and are covered by the claims.

All publications and patent applications mentioned in the specification are indicative of the level of skill of those skilled in the art to which this invention pertains. All publications and patent applications are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.

The use of the word "a" or "an" when used in conjunction with the term "comprising" in the claims and/or the specification may mean "one," but it is also consistent with the meaning of "one or more," "at least one," and "one or more than one." The use of the term "or" in the claims is used to mean "and/or" unless explicitly indicated to refer to alternatives only or the alternatives are mutually exclusive, although the disclosure supports a definition that refers to only alternatives and "and/or." Throughout this application, the term "about" is used to indicate that a value includes the inherent variation of error for the device, the method being employed to determine the value, or the variation that exists among the study subjects.

As used in this specification and claim(s), the words "comprising" (and any form of comprising, such as "comprise" and "comprises"), "having" (and any form of having, such as "have" and "has"), "including" (and any form of including, such as "includes" and "include") or "containing" (and any form of containing, such as "contains" and "contain") are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.

The term "or combinations thereof as used herein refers to all permutations and combinations of the listed items preceding the term. For example, "A, B, C, or combinations thereof is intended to include at least one of: A, B, C, AB, AC, BC, or ABC, and if order is important in a particular context, also BA, CA, CB, CBA, BCA, ACB, BAC, or CAB. Continuing with this example, expressly included are combinations that contain repeats of one or more item or term, such as BB, AAA, AB, BBC, AAABCCCC, CBBAAA, CABABB, and so forth. The skilled artisan will understand that typically there is no limit on the number of items or terms in any combination, unless otherwise apparent from the context.

All of the compositions and/or methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the compositions and methods of this invention have been described in terms of preferred embodiments, it will be apparent to those of skill in the art that variations may be applied to the compositions and/or methods and in the steps or in the sequence of steps of the method described herein without departing from the concept, spirit and scope of the invention. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and concept of the invention as defined by the appended claims.

Claims

What is claimed is:

1. A method of recovering one or more oils from a liquid using one or more membrane or membrane contactors, comprising the steps of:

pumping the liquid comprising the one or more oils into contact with a first surface of the one or more membranes or membrane contactors;

coalescing the one or more oils from the liquid onto the first surface of the one or more membrane or membrane contactors; and

collecting a stream of coalesced oil from the second surface of the one or more membrane or membrane contactors, wherein the stream comprises the oils without the need for a counterflowing recovery fluid.

2. The method of claim 1, wherein the liquid is selected from at least one of oily water, oil industry waste streams, oil contaminated water or brine, wastewater, contaminated oil, oil containing drainage water, water contaminated with oil, seawater contaminated with oil, brine contaminated with oil, industrial effluents that comprise oil, natural effluents that comprise oil, drilling mud, tailing ponds, leach residue, produced water, oil sands tailing, frac water, connate water, an oil/water/solid mixture, a gravity separated oil/water/solid mixture, water-oil mixtures, aqueous slurries, aqueous slurries comprising broken cells, live cells or organisms, biocellular mixtures, lysed cellular preparations, or lipophobic contaminants that have not been separated or have been separated by at least one of gravity, centrifugal, centripedal, or hydrocyclone separation.

3. The method of claim 1, wherein the liquid is processed by the method within 1, 2, 4, 6, 8, 12, 24, 26, 48 or 72 hours from production.

4. The method of claim 1, wherein the liquid contains one or more organisms that include at least one of intact cells, lysed cells, apoptotic cells, necrotic cells, wherein organisms comprises two or more different organisms, wherein organism is a yeast, algae or bacteria, or wherein the organism is capable of secreting oil or causing the accumulation of oil outside living cells.

5. The method of claim 1, wherein the liquid contains one or more organisms that are genetically modified to render them capable of secreting hydrophobic components, organisms that are capable of causing accumulation of the one or more hydrophobic components outside living cells, organisms that are capable of causing accumulation of the one or more hydrophobic components outside living cells upon induction with one or more chemical probes, exogenous agents, or pharmaceuticals, or combinations thereof.

6. The method of claim 1, further comprising contacting the organism with chemical probes, exogenous agents, or pharmaceuticals, whereby the metabolism of the one or more organism is modified, wherein at least one organism causes accumulation of the one or more oils outside living cells.

7. The method of claim 1, further comprising the step of contacting the one or more oils in the liquid source to remove oil, then returning the aqueous mixture to a growth environment.

8. The method of claim 1, wherein 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%o, 99%o or 100%o of the one or more insoluble oils in the liquid source are recovered.

9. The method of claim 1, wherein the source of the liquid is a growth media for algae, bacteria or yeast and the insoluble oils are recovered the using one or more membrane or membrane contactors comprising the steps of:

contacting the growth media comprising organisms and insoluble oils with a first surface in the one or more membrane or membrane contactors;

removing a first stream from the contactor or the vessel, wherein the first stream comprises the growth media and organisms, wherein the organisms can continue to produce the insoluble oils; and removing a second stream from the second surface of one or more membrane or membrane contactors, wherein the second stream comprises the one or more insoluble oils without the need for a recovery fluid.

10. The method of claim 9, further comprising feeding or pumping the stream to the growth environment to resume oil production by the organisms.

11. The method of claim 9, wherein the one or more membrane or membrane contactors are selected from at least one of polyethylene, polypropylene, polyolefins, polyvinyl chloride (PVC), amorphous Polyethylene terephthalate (PET), polyolefin copolymers, poly(etheretherketone) type polymers, surface modified polymers, or surface modified polymers comprise polymers modified chemically at one or more halogen groups by corona discharge or by ion embedding techniques.

12. A system for recovering one or more oils from a liquid comprising using one or more non- dispersive membrane or membrane contactors, comprising the steps of:

a source of a stream of the liquid comprising oil;

a pump that circulates the aqueous mixture comprising the one or more oils to a first surface of the one or more membrane or membrane contactors, wherein the one or more oils coalesce at the first surface of the one or more membrane or membrane contactors; and

a collection conduit or vessel in communication with a collection stream from a second surface of the one or more membrane or membrane contactors, wherein the collection stream comprises the oils without the need for a counterflowing recovery fluid.

13. The system of claim 12, wherein the liquid contains one or more organisms that include at least one of intact cells, lysed cells, apoptotic cells, or necrotic cells, comprises two or more different organisms, comprise yeast, algae or bacteria or comprise organisms capable of secreting oil or causing the accumulation of oil outside living cells.

14. The system of claim 12, wherein the liquid contains one or more organisms that are genetically modified to render them capable of secreting hydrophobic components, organisms that are capable of causing accumulation of the one or more hydrophobic components outside living cells, organisms that are capable of causing accumulation of the one or more hydrophobic components outside living cells upon induction with one or more chemical probes, exogenous agents, or pharmaceuticals, or combinations thereof.

15. The system of claim 12, further comprising contacting the organism with chemical probes, exogenous agents, or pharmaceuticals, whereby the metabolism of the one or more organism is modified, wherein at least one organism causes accumulation of the one or more oils outside living cells.

16. The system of claim 12, further comprising the step of contacting the one or more oils in the liquid to remove oil, then returning the liquid to a growth environment.

17. The system of claim 12, wherein 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%o, 99%o or 100%o of the one or more insoluble oils in the liquid source are recovered.

18. The system of claim 12, wherein the one or more membrane or membrane contactors area selected from at least one of polyethylene, polypropylene, poly olefins, polyvinyl chloride (PVC), amorphous Polyethylene terephthalate (PET), polyolefin copolymers, poly(etheretherketone) type polymers, surface modified polymers, or surface modified polymers modified chemically at one or more halogen groups by corona discharge or by ion embedding techniques.

19. The system of claim 12, wherein once the system is collecting oil, further comprising the step of counterflowing a recovery fluid that comprises the same oil recovered in the initial operation of the contactor.