[go: up one dir, main page]

WO2018175330A1 - Enzymes pouvant éliminer les composés sulfureux présents dans les fluides de fond de trou - Google Patents

Enzymes pouvant éliminer les composés sulfureux présents dans les fluides de fond de trou Download PDF

Info

Publication number
WO2018175330A1
WO2018175330A1 PCT/US2018/023159 US2018023159W WO2018175330A1 WO 2018175330 A1 WO2018175330 A1 WO 2018175330A1 US 2018023159 W US2018023159 W US 2018023159W WO 2018175330 A1 WO2018175330 A1 WO 2018175330A1
Authority
WO
WIPO (PCT)
Prior art keywords
fluid
enzyme
cysteine synthase
fluids
sulfide
Prior art date
Application number
PCT/US2018/023159
Other languages
English (en)
Inventor
Prasad Dhulipala
Jerry Weers
Soma Chakraborty
Marilyn Blaschke
Original Assignee
Baker Hughes, A Ge Company, Llc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US15/467,687 external-priority patent/US20170260074A1/en
Application filed by Baker Hughes, A Ge Company, Llc filed Critical Baker Hughes, A Ge Company, Llc
Publication of WO2018175330A1 publication Critical patent/WO2018175330A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/34—Biological treatment of water, waste water, or sewage characterised by the microorganisms used
    • C02F3/342—Biological treatment of water, waste water, or sewage characterised by the microorganisms used characterised by the enzymes used
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C02F2101/101—Sulfur compounds
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
    • C02F2103/34—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32
    • C02F2103/36—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32 from the manufacture of organic compounds
    • C02F2103/365—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32 from the manufacture of organic compounds from petrochemical industry (e.g. refineries)

Definitions

  • the present invention relates to additive compositions, fluid compositions, and methods for using at least one cysteine synthase enzyme and at least one sulfide quinone reductase enzyme in a downhole fluid, and more specifically relates to decreasing or removing sulfur-containing compounds using at least one cysteine synthase enzyme and at least one sulfide quinone reductase enzyme.
  • sulfur-rich hydrocarbon streams also produce heavy environmental pollution.
  • sulfur species lead to brittleness in carbon steels and to stress corrosion cracking in more highly alloyed materials.
  • hydrogen sulfides in various hydrocarbon or aqueous streams pose a safety hazard and a corrosion hazard. A quick removal of these odorous and environmentally malicious species would be desirable in both oilfield and refinery operations.
  • Glyoxal is another nitrogen-free hydrogen sulfide sweetener, but its application is often limited due to its corrosivity and low boiling point. Metal oxides have also been proposed, but such applications are narrowed by the handling challenges and solid residual formation concerns to downstream refining catalysts and processes.
  • Acrolein is a clean and extremely potent hydrogen sulfide/mercaptan sweetener, but it requires special handling due to toxicity concerns.
  • Sulfur-containing compounds are deleterious in the subterranean reservoir wellbores in which they reside.
  • Additives may be added to the downhole fluids for circulation into the reservoir wellbore.
  • the downhole fluids may be or include drilling fluids, completion fluids, servicing fluids (e.g. fracturing fluids), production fluids, injection fluids, and combinations thereof.
  • Drilling fluids are typically classified according to their base fluid.
  • solid particles such as weighting agents, are suspended in a continuous phase consisting of water or brine. Oil can be emulsified in the water, which is the continuous phase.
  • Water-based fluid is used herein to include fluids having an aqueous continuous phase where the aqueous continuous phase can be all water or brine, an oil-in-water emulsion, or an oil-in-brine emulsion.
  • Brine-based fluids of course are water-based fluids, in which the aqueous component is brine.
  • Oil-based fluids are the opposite or inverse of water-based fluids.
  • Oil-based fluid is used herein to include fluids having a non-aqueous continuous phase where the non-aqueous continuous phase is all oil, a nonaqueous fluid, a water-in-oil emulsion, a water-in- non-aqueous emulsion, a brine-in-oil emulsion, or a brine-in-non-aqueous emulsion.
  • solid particles are suspended in a continuous phase consisting of oil or another non-aqueous fluid. Water or brine can be emulsified in the oil; therefore, the oil is the continuous phase.
  • oil-based fluids the oil may consist of any oil or water-immiscible fluid that may include, but is not limited to, diesel, mineral oil, esters, refinery cuts and blends, or alpha-olefins.
  • Oil-based fluid as defined herein may also include synthetic-based fluids or muds (SBMs), which are synthetically produced rather than refined from naturally-occurring materials.
  • SBMs synthetic-based fluids or muds
  • Synthetic-based fluids often include, but are not necessarily limited to, olefin oligomers of ethylene, esters made from vegetable fatty acids and alcohols, ethers and polyethers made from alcohols and polyalcohols, paraffinic, or aromatic, hydrocarbons alkyl benzenes, terpenes and other natural products and mixtures of these types.
  • Completion fluids are typically brines, such as chlorides, bromides, and/or formates, but may be any non- damaging fluid having proper density and flow characteristics.
  • Suitable salts for forming the brines include, but are not necessarily limited to, sodium chloride, calcium chloride, zinc chloride, potassium chloride, potassium bromide, sodium bromide, calcium bromide, zinc bromide, sodium formate, potassium formate, ammonium formate, cesium formate, and mixtures thereof. Chemical compatibility of the completion fluid with the reservoir formation and formation fluids is key.
  • Chemical additives such as polymers and surfactants are known in the art for being introduced to the brines used in well servicing fluids for various reasons that include, but are not limited to, increasing viscosity, and increasing the density of the brine.
  • Completion fluids do not contain suspended solids.
  • Production fluid is the fluid that flows from a formation to the surface of an oil well.
  • These fluids may include oil, gas, water, as well as any contaminants (e.g. H 2 S, asphaltenes, etc.).
  • the consistency and composition of the production fluid may vary.
  • Refinery fluids may be any fluid circulating through a refinery process, such as a fluid that may be further processed or refined at a refinery, a fluid circulated through a particular aspect of a refinery for cleaning refinery equipment, and combinations thereof.
  • a non-limiting example of a refinery process may include reducing or preventing the formation of foulants.
  • foulants may be or include hydrates, asphaltenes, coke, coke precursors, naphthenates, inorganic solid particles (e.g. sulfates, oxides, scale, and the like), and combinations thereof.
  • Non-limiting examples of fluids to be refined include crude oil, production water, sour water, and combinations thereof.
  • servicing fluids such as remediation fluids, stimulation fluids, workover fluids, and the like, have several functions and characteristics necessary for repairing a damaged well.
  • Such fluids may be used for breaking emulsions already formed and for removing formation damage that may have occurred during the drilling, completion and/or production operations.
  • the terms "remedial operations” and “remediate” are defined herein to include a lowering of the viscosity of gel damage and/or the partial or complete removal of damage of any type from a subterranean formation.
  • the term “remediation fluid” is defined herein to include any fluid that may be useful in remedial operations.
  • a stimulation fluid may be a treatment fluid prepared to stimulate, restore, or enhance the productivity of a well, such as fracturing fluids and/or matrix stimulation fluids in one non-limiting example.
  • Hydraulic fracturing is a type of stimulation operation, which uses pump rate and hydraulic pressure to fracture or crack a subterranean formation in a process for improving the recovery of hydrocarbons from the formation.
  • high permeability proppant relative to the formation permeability is pumped into the fracture to prop open the crack.
  • the crack or fracture cannot close or heal completely because the high permeability proppant keeps the crack open.
  • the propped crack or fracture provides a high permeability path connecting the producing wellbore to a larger formation area to enhance the production of hydrocarbons.
  • fracturing fluids must simultaneously meet a number of conditions. For example, they must be stable at high temperatures and/or high pump rates and shear rates that can cause the fluids to degrade and prematurely settle out the proppant before the fracturing operation is complete.
  • fracturing fluids are aqueous based liquids that have either been gelled or foamed to better suspend the proppants within the fluid.
  • Injection fluids may be used in enhanced oil recovery (EOR) operations, which are sophisticated procedures that use viscous forces and/or interfacial forces to increase the hydrocarbon production, e.g. crude oil, from oil reservoirs.
  • EOR enhanced oil recovery
  • the EOR procedures may be initiated at any time after the primary productive life of an oil reservoir when the oil production begins to decline.
  • the efficiency of EOR operations may depend on reservoir temperature, pressure, depth, net pay, permeability, residual oil and water saturations, porosity, fluid properties, such as oil API gravity and viscosity, and the like.
  • EOR operations are considered a secondary or tertiary method of hydrocarbon recovery and may be necessary when the primary and/or secondary recovery operation has left behind a substantial quantity of hydrocarbons in the subterranean formation.
  • Primary methods of oil recovery use the natural energy of the reservoir to produce oil or gas and do not require external fluids or heat as a driving energy; EOR methods are used to inject materials into the reservoir that are not normally present in the reservoir.
  • Secondary EOR methods of oil recovery inject external fluids into the reservoir, such as water and/or gas, to re-pressurize the reservoir and increase the oil displacement.
  • Tertiary EOR methods include the injection of special fluids, such as chemicals, miscible gases and/or thermal energy.
  • the EOR operations follow the primary operations and target the interplay of capillary and viscous forces within the reservoir.
  • the energy for producing the remaining hydrocarbons from the subterranean formation may be supplied by the injection of fluids into the formation under pressure through one or more injection wells penetrating the formation, whereby the injection fluids drive the hydrocarbons to one or more producing wells penetrating the formation.
  • EOR operations are typically performed by injecting the fluid through the injection well into the subterranean reservoir to restore formation pressure, improve oil displacement or fluid flow in the reservoir, and the like.
  • Examples of EOR operations include water-based flooding and gas injection methods. Water-based flooding may also be termed 'chemical flooding' if chemicals are added to the water-based injection fluid. Water-based flooding may be or include, polymer flooding, ASP (alkali/surfactant/polymer) flooding, SP (surfactant/polymer) flooding, low salinity water and microbial EOR; gas injection includes immiscible and miscible gas methods, such as carbon dioxide flooding, and the like.
  • an additive composition to be added to a base fluid such as but not limited to, a drilling fluid, a completion fluid, a production fluid, a servicing fluid, an injection fluid, a refinery fluid, and combinations thereof.
  • the additive may have or include at least one cysteine synthase enzyme and at least one sulfide quinone reductase enzyme.
  • the cysteine synthase enzyme(s) may be at least 75% homologous to the cDNA sequence of SEQ ID NO: 1 .
  • the sulfide quinone reductase enzyme(s) may be at least 75% homologous to the cDNA sequence of SEQ ID NO:2.
  • a fluid composition having a base fluid, at least one cysteine synthase enzyme, and at least one sulfide quinone reductase enzyme.
  • the cysteine synthase enzyme(s) may be at least 75% homologous to the cDNA sequence of SEQ ID NO: 1 .
  • the sulfide quinone reductase enzyme(s) may be at least 75% homologous to the cDNA sequence of SEQ ID NO:2.
  • the base fluid may be or include, but is not limited to, drilling fluids, servicing fluids, production fluids, completion fluids, injection fluids, refinery fluids, and combinations thereof.
  • a method may include contacting at least one fluid with at least one cysteine synthase enzyme and at least one sulfide quinone reductase enzyme in an effective concentration to decrease an amount of sulfur-containing compounds.
  • the cysteine synthase enzyme may be at least 75% homologous to the cDNA sequence of SEQ ID NO: 1
  • the sulfide quinone reductase enzyme(s) may be at least 75% homologous to the cDNA sequence of SEQ ID NO:2.
  • cysteine synthase enzymes and the sulfide quinone reductase enzymes appear to remove hydrogen sulfide from recovered downhole fluids and/or in subterranean reservoir wellbores.
  • FIG. 1 (SEQ ID NO: 1 ) represents the nucleotide sequence that codes for the cysteine synthase enzyme
  • FIG. 2 represents the plasmid pBEn-SET3a used for expressing the cysteine synthase enzyme
  • FIG. 3 is a graph depicting the effect of reaction components on cysteine synthase activity where the cysteine formed was treated with acid ninhydrin, and the absorbance was measured with a spectrometer at 560 nm;
  • FIG. 4 is a graph depicting the hydrogen sulfide levels measured by colorimetry using an HACH sulfide assay
  • FIG. 5 is a graph depicting an amount of H 2 S measured in head space after treating a bottle or condition containing an equilibrated sulfide and hydrogen sulfide where the measurements were acquired by using gas chromatography;
  • FIG. 6 represents the nucleotide sequence that codes for the sulfide quinone reductase enzyme
  • FIG. 7 is a graph depicting use of a cysteine synthase enzyme and a sulfide quinone reductase enzyme in sour water;
  • FIG. 8 is another graph depicting use of a cysteine synthase enzyme and a sulfide quinone reductase enzyme in sour water;
  • FIG. 9 is a graph depicting a combination of cysteine synthase enzyme and sulfide quinone reductase enzyme use to decrease a percentage of sodium sulfide in a solution;
  • FIG. 10 is another graph depicting a combination of cysteine synthase enzyme and sulfide quinone reductase enzyme use to decrease a percentage of sulfide in a sour refinery water.
  • an additive composition having at least one cysteine synthase enzyme and at least one sulfide quinone reductase enzyme may be added to a base fluid to decrease an amount of sulfur- containing compounds in the base fluid.
  • a fluid composition comprising a cysteine synthase enzyme and a sulfide quinone reductase enzyme may be circulated in a subterranean reservoir wellbore to decrease an amount of sulfur-species compounds present in the subterranean reservoir wellbore and/or any downhole fluids recovered therefrom.
  • cysteine synthase enzyme(s) and the sulfide quinone reductase enzyme(s) may be less toxic to the environment and may be made from renewable resources.
  • the use of cysteine synthase enzyme(s) and sulfide quinone reductase enzyme(s) in a base fluid may provide a renewable alternative to conventional additives (non-biodegradable) that are used in downhole fluids to decrease sulfur-containing compounds.
  • the cysteine synthase may be or include, but is not limited to, O-Acetyl-Serine Sulfhydrylase (OASS).
  • OASS O-Acetyl-Serine Sulfhydrylase
  • the cysteine synthase enzyme(s) and sulfide quinone reductase enzymes may be derived from various organisms.
  • the cysteine synthase enzyme(s) may be derived from Aeropyrum pernix.
  • the additive and/or fluid composition may further include an additional component, such as but not limited to, a pyridoxal phosphate, O- acetyl-serine, DTT, coenzyme Q10, plastoquinone, vitamin K2, and combinations thereof; the additional component(s) may be added to the base fluid at the same time or a different time from the cysteine synthase enzyme(s) and at the same time or different time from the sulfide quinone reductase enzyme(s).
  • an additional component such as but not limited to, a pyridoxal phosphate, O- acetyl-serine, DTT, coenzyme Q10, plastoquinone, vitamin K2, and combinations thereof; the additional component(s) may be added to the base fluid at the same time or a different time from the cysteine synthase enzyme(s) and at the same time or different time from the sulfide quinone reductase enzyme(s).
  • the additional component(s) may be added to the base fluid in a concentration ranging from about 0.25 mM independently to about 20 mM, alternatively from about 0.1 mM independently to about 15 mM, or from about 1 mM independent to about 5 mM in another non-limiting embodiment.
  • pyridoxal phosphate may be added to the base fluid in a concentration ranging from about 0.1 mM independently to about 5 mM, alternatively from about 1 mM independently to about 4 mM.
  • the additive and/or fluid composition does not include pyridoxal phosphate.
  • the DTT may be added to the base fluid in a concentration ranging from about 0.25 mM independently to about 5 mM, alternatively from about 1 mM independently to about 3 mM.
  • the cysteine synthase enzyme(s) and/or the sulfide quinone reductase enzyme(s) may be added to the base fluid in a concentration substantially equal to or more than the amount of suspected sulfur-containing compounds present in the base fluid and/or the subterranean reservoir wellbore.
  • the cysteine synthase enzyme(s) may be added to the base fluid in a concentration ranging from about 1 mM independently to about 20 mM, alternatively from about 5 mM independently to about 15 mM.
  • the sulfide quinone reductase enzyme(s) may be added to the base fluid in a concentration ranging from about 1 mM independently to about 20 mM, alternatively from about 5 mM independently to about 15 mM.
  • Cysteine synthase enzymes and sulfide quinone reductase enzyme(s) may remove or decrease sulfur-containing compounds, e.g. hydrogen sulfide (H 2 S) or other types of mercaptans in a non-limiting embodiment, within a recovered downhole fluid from a subterranean reservoir wellbore and/or decrease the amount of hydrogen sulfide or other sulfur- containing compounds in the wellbore from which the downhole fluid was recovered.
  • sulfur-containing compounds may be or include, but is not limited to any compound having the formula R-SH where R is an unsubstituted or substituted alkyl, thiol, carboxylic acid, dithio acid, and combinations thereof.
  • R may have or include from 1 independently to 40 carbons, alternatively, from 6 independently to about 20 carbons.
  • the cysteine synthase enzyme may catalyze the reaction of an O- acetyl-L-serine and hydrogen sulfide to form L-cysteine and acetate.
  • hydrogen sulfide is converted into L-cysteine in a 1 : 1 ratio, i.e. one mole of H 2 S forms one mole of L-cysteine.
  • O-acetyl-L-serine and hydrogen bind to the enzyme in a 1 : 1 ratio.
  • the sulfide quinone reductase enzyme may catalyze the reaction of a quinone (e.g. coenzyme Q10, plastoquinone, vitamin K2, and combinations thereof in a non-limiting embodiment) and hydrogen sulfide to form quinol and an oxidation product, such as but not limited to elemental sulfur, a sulfite, polysulfide and combinations thereof.
  • a quinone e.g. coenzyme Q10, plastoquinone, vitamin K2, and combinations thereof in a non-limiting embodiment
  • hydrogen sulfide to form quinol and an oxidation product, such as but not limited to elemental sulfur, a sulfite, polysulfide and combinations thereof.
  • 'Enzyme' as used within 'cysteine synthase enzyme' and/or 'sulfide quinone reductase enzyme' is defined herein to be the active site of each respective enzyme to convert sulfur-containing products into less hazardous materials, such as but not limited to L-cysteine, elemental sulfur, a sulfite, polysulfide, acetate, and combinations thereof.
  • the active site of the enzyme may be or include the whole protein, an active fragment of the protein, a mimetic of the protein, and combinations thereof.
  • 'Fragment' as used herein is meant to include any amino acid sequence shorter than the full-length enzyme, but where the fragment maintains similar activity to the full-length enzyme.
  • Fragments may include a single contiguous sequence identical to a portion of the enzyme sequence.
  • the fragment may have or include several different shorter segments where each segment is identical in amino acid sequence to a different portion of the amino acid sequence of the enzyme, but linked via amino acids differing in sequence from the enzyme.
  • 'Mimetic' as used herein may include polypeptides, which may be recombinant, and peptidomimetics, as well as small organic molecules, which exhibit similar or enhanced catalytic activity as compared to the enzymes described herein.
  • the gene for the cysteine synthase enzyme may be codon optimized to increase the efficiency of its expression in E. coli.
  • the nucleotide sequence of one embodiment of the cysteine synthase enzyme is set forth in FIG.
  • the gene coding for the cysteine synthase enzyme may have a nucleotide sequence that is substantially homologous to the nucleotide sequence of FIG. 1 (SEQ ID NO: 1 ).
  • the term "substantially homologous” is used herein to denote nucleotides having at least 75% sequence identity to the sequence shown in FIG. 1 (SEQ ID NO: 1 ), alternatively from about 80% independently to about 99.5%, or from about 85% independently to about 95%.
  • “independently” means that any threshold may be used together with another threshold to give a suitable alternative range, e.g. about 75% independently to about 85% is also considered a suitable alternative range.
  • the gene for the sulfide quinone reductase enzyme may be codon optimized to increase the efficiency of its expression in E. coli.
  • the nucleotide sequence of one embodiment of the sulfide quinone reductase is set forth in FIG. 6 (SEQ ID NO:2).
  • the gene coding for the sulfide quinone reductase enzyme may have a nucleotide sequence that is substantially homologous to the nucleotide sequence of FIG. 6 (SEQ ID NO:2).
  • the term "substantially homologous" is used herein to denote nucleotides having at least 75% sequence identity to the sequence shown in FIG. 6 (SEQ ID NO:2), alternatively from about 80% independently to about 99.5%, or from about 85% independently to about 95%.
  • the cysteine synthase enzyme may be a homodimer, i.e. two subunits that are the same, where each subunit may have a pyridoxal phosphate as a cofactor. However, as previously mentioned, the cysteine synthase enzyme may function in the absence of a pyridoxal phosphate cofactor.
  • the primary structural sequence of an enzyme is the linear sequence of amino acids that are linked together by peptide bonds to form the primary structure of the cysteine synthase enzyme and/or the sulfide quinone reductase enzyme.
  • the secondary structure of the protein refers to the base pairing interactions within a single molecule or set of interacting molecules, such as a beta-helix in the cysteine synthase enzyme and/or the sulfide quinone reductase enzyme.
  • Tertiary structure refers to the three-dimensional structure of the cysteine synthase enzyme and/or the sulfide quinone reductase enzyme formed from the nucleotide sequence. Quaternary structure refers to the interaction between at least two tertiary structures.
  • a particular bacterium known for producing the respective enzyme may be plated on a growth medium, such as an agar, which is conducive to the growth of the particular bacterium in a non-limiting embodiment.
  • Aeropyrum pernix may be plated on a growth medium for growing the Aeropyrum pernix bacterium for subsequently producing a cysteine synthase enzyme.
  • the enzyme may be directly isolated from its bacteria to be added to or used within a fluid composition for decreasing a sulfur-containing compound in a fluid composition and/or a subterranean reservoir wellbore.
  • cysteine synthase enzyme and/or the sulfide quinone reductase enzyme has been removed from the intact cells or cellular debris, and is in a condition other than its native environment, is free of other extraneous or unwanted nucleic acids, proteases, and lipids, in a form suitable for use as a cysteine synthase enzyme and/or the sulfide quinone reductase enzyme as described herein.
  • a particular gene of a cysteine synthase gene from the Aeropyrum pernix bacterium may be inserted into a plasmid vector.
  • a gene of the sulfide quinone reductase gene may be inserted into a plasmid vector.
  • a vector is a DNA molecule that may be used as a vehicle to artificially carry genetic material from a foreign cell and/or organism.
  • a plasmid is defined as a circular extrachromosomal element found naturally in bacteria and some other organisms, which may be genetically engineered to clone DNA fragments.
  • the plasmid may then be inserted into a host bacterium cell, such as Escherichia coli, where the host cell may replicate and/or express the foreign DNA.
  • the E. coli cells may be plated on a growth medium, such as an agar, which is conducive to the growth of E. coli.
  • the growth of E coli propagates the enzyme as clones within each E. coli cell.
  • the enzyme(s) may be isolated from the E. coli cells and added to or used within a fluid composition.
  • FIG. 2 is a depiction of the plasmid pBEn-SET3a before cloning the cysteine synthase enzyme thereinto.
  • P T7/lacO is a promoter site with a lac operator, which is a site for starting transcription.
  • the extended RBS is a ribosomal binding site that is a sequence on mRNA that is bound by a ribosome when initiating protein translation.
  • the SET3tag may increase the solubility of any problem proteins within E. coli. Although the mechanism by which the SET tag may improve solubility has not been confirmed, the SET tag may enhance solubility of the fusion protein by providing a net negative charge, which is thought to prevent aggregation and provide more time for correct protein folding in vivo.
  • the multiple cloning site is a short segment of DNA that has several restriction sites, such as Nde1 and BamH1 in a non-limiting embodiment.
  • Nde1 is a type II restriction enzyme that may cut open specific sequence targets; specifically, Nde1 may be used to cut open the reading frames in the plasmid to insert the cysteine synthase enzyme genes.
  • Bam ⁇ is also a type II restriction endonuclease that recognizes the sequence 5'- GGATCC-3', and cleaves these sequences just after the 5'-guanine on each strand to leave sticky ends that are 4 base pairs long.
  • pBR322 oh is the DNA sequence that signals for the origin of replication (also known as Origin'), and lacl codes for the lactose repressor.
  • the E coli cells may be harvested via centrifugation to produce a cell pellet.
  • the cell pellet may be lysed either by physical means or by chemical means, such as detergents and/or enzymes (e.g. lysozyme) to produce a lysate.
  • the raw lysate may contain the recombinant protein, as well as other proteins originating from the bacterial host.
  • the cysteine synthase enzyme and/or the sulfide quinone reductase enzyme may be in a powder form and/or a liquid form (e.g.
  • the cysteine synthase enzyme and/or the sulfide quinone reductase enzyme may be part of an additive where the additive includes the cysteine synthase enzyme and/or the sulfide quinone reductase enzyme, as well as other components to aid the cysteine synthase enzyme and/or the sulfide quinone reductase enzyme in decreasing the amount of sulfur-containing compounds in a fluid composition and/or a subterranean reservoir wellbore.
  • the additive may include a cysteine synthase enzyme and/or the sulfide quinone reductase enzyme where the cysteine enzyme is at least 75% homologous to the cDNA sequence of SEQ ID NO: 1 and where the sulfide quinone reductase enzyme is at least 75% homologous to the cDNA sequence of SEQ ID NO:2.
  • cDNA is defined herein as DNA synthesized from a messenger RNA (mRNA) template in an enzymatic catalyzed reaction using reverse transcriptase.
  • the additive may include the cysteine synthase enzyme and/or the sulfide quinone reductase enzyme within the additive composition in a concentration ranging from about 1 nanomolar (nM) independently to about 5 millimolar (mm), alternatively from about 10 nM independently to about 1 mm, or from about 1 micromolar ( ⁇ ) independently to about 5 ( ⁇ ) as compared to the total base fluid.
  • nM nanomolar
  • mm millimolar
  • ⁇ micromolar
  • the reaction where sulfur-containing components are catalyzed into less hazardous materials via at least one of the cysteine synthase and/or the sulfide quinone reductase enzyme(s) may occur for at least 30 minutes, alternatively from about 30 minutes independently to about 4 hours, or from about 1 hour independently to about 4 hours.
  • the cysteine synthase enzyme and/or the sulfide quinone reductase enzyme may maintain optimal function at a temperature ranging from about 75°F independently to about 200° F, alternatively from about 100° F independently to about 175° F.
  • the cysteine synthase enzyme and/or the sulfide quinone reductase enzyme may maintain optimal function at a pressure less than about 15,000 pounds per square inch (psi).
  • the cysteine synthase enzyme and/or the sulfide quinone reductase enzyme may maintain optimal function at a pH ranging from about 4 independently to about 1 1 , alternatively from about 5 independently to about 8, or from about 6 to about 7.5 in another non-limiting embodiment.
  • the cysteine synthase enzyme and/or the sulfide quinone reductase enzyme may still function at a decreased reaction rate, if at all, outside of the ranges mentioned for temperature, pressure, and/or pH.
  • the additive may be added to a base fluid to form a fluid composition.
  • the base fluid may be or include, but is not limited to, a drilling fluid, a completion fluid, a production fluid, a servicing fluid, an injection fluid, a refinery fluid, and combinations thereof.
  • the base fluid may be an aqueous fluid, a non-aqueous fluid, an organic fluid, and combinations thereof.
  • the base fluid or fluid composition may be contained in an oil pipeline, gas pipeline, a storage tank, a transportation vehicle, a refinery (e.g. separation vessels, dehydration units, gas lines, and pipelines), and combinations thereof.
  • the cysteine synthase enzyme(s) having at least 75% homology to the cDNA sequence of SEQ ID NO: 1 may be circulated into a subterranean reservoir wellbore to decrease an amount of sulfur-containing compounds within the subterranean reservoir wellbore and/or any downhole fluids recovered therefrom.
  • the sulfide quinone reductase enzyme(s) having at least 75% homology to the cDNA sequence of SEQ ID NO:2 may be circulated into a subterranean reservoir wellbore to decrease an amount of sulfur-containing compounds within the subterranean reservoir wellbore and/or any downhole fluids recovered therefrom.
  • cysteine synthase enzyme(s) and/or the sulfide quinone reductase enzyme(s) may be circulated into an oil pipeline, gas pipeline, a storage tank, a transportation vehicle, a refinery (e.g. separation vessels, dehydration units, gas lines, and pipelines), and combinations thereof.
  • a refinery e.g. separation vessels, dehydration units, gas lines, and pipelines
  • the cysteine synthase enzyme(s) and the sulfide quinone reductase enzyme(s) may be circulated at the same time or different times.
  • 'Same time' is defined herein to be substantially the same time, i.e. both enzymes are added to a base fluid or fluid composition prior to circulating the fluid composition through a subterranean reservoir wellbore and/or refinery equipment and/or storage/transportation equipment.
  • 'Different times' is defined herein to mean the sulfide quinone reductase enzymes may be added separately to a base fluid or fluid composition before or after the cysteine synthase enzyme is added to the same base fluid or fluid composition.
  • the sulfide quinone reductase enzymes and the cysteine synthase enzymes are considered to be added/used 'in combination' to decrease the sulfur-containing components when added to the same base fluid or fluid composition.
  • the cysteine synthase enzyme(s) and the sulfide quinone reductase enzyme(s) may be used together but in different concentrations.
  • sulfide quinone reductase enzymes is currently less expensive than cysteine synthase enzymes; therefore, the sulfide quinone reductase enzyme(s) may be added to either a base fluid(s) and/or the fluid composition(s) first to decrease the sulfur-containing compounds as much as possible. Then, the cysteine synthase enzyme(s) may be added to the same base fluid or fluid composition to further decrease the sulfur-containing compounds below a pre-determined threshold.
  • a greater concentration of the sulfide quinone reductase enzyme may be used because it is currently less expensive than the cysteine synthase enzymes.
  • the cysteine synthase enzymes may be used in a greater concentration as compared to the sulfide quinone reductase enzymes in another non-limiting embodiment.
  • the cysteine synthase enzymes and the sulfide quinone reductase enzymes may be used in substantially the same concentrations.
  • the fluid composition may include a salt, such as but not limited to, a brine, sea salt, and combinations thereof.
  • the brine may be or include, but is not limited to potassium chloride, sodium chloride, calcium chloride, zinc chloride, potassium bromide, sodium bromide, calcium bromide, zinc bromide, sodium formate, potassium formate, ammonium formate, cesium formate, and combinations thereof.
  • 'Derived from' with respect to the enzymes is meant to include whole enzymes or enzyme fragments, where the enzyme originated from its respective bacterium and was isolated from its particular species; 'derived from' also encompasses polypeptides identical in DNA and/or amino acid sequence to the active site (e.g. the cleft between C and N terminal domains and Lysine 47 site of the cysteine synthase enzyme in a non-limiting example) of the bacterium that are recombinantly expressed in a host cell expression system or chemically synthesized.
  • 'Recombinant DNA' is DNA that has been formed artificially by combining constituents from different organisms, such as inserting the enzyme into an £. coii host ceil for a cloned reproduction of the cysteine synthase enzyme in a non-limiting example.
  • 'Derived from' also includes derivatives of the enzymes, such as a polypeptide or fragment that may be substantially similar in primary structural sequence to the enzymes described herein, but which may include chemical and/or biochemical modifications that are not found in the native polypeptide.
  • modifications may be or include, but are not limited to a label, such as a radioactive isotope, a fluorophore, or an enzymatic label useful in tracing the enzymes.
  • the label or other modification may be useful in isolating the enzymes from the bacterium and/or other expression system (E. coli as described below).
  • the label or other modification may be used to identify the enzymes within a fluid composition and/or recovering the enzyme from the fluid composition.
  • Other non-limiting modifications may be or include a nucleotide mutagenesis to impart additional thermostability and pH tolerance to the enzymes.
  • the method may include decreasing the amount of at least one sulfur-containing compound within the fluid composition and/or within a subterranean reservoir wellbore, storage facility, transportation vehicle, a refinery, and combinations thereof.
  • Parameters that may be used to assess the effectiveness of the enzymes may include measurements of formation kinetics where the sulfur-containing compounds are catalyzed into their respective oxidized components, amount of sulfur-containing compounds present in the recovered fluids, fluid compositions, and/or subterranean reservoir wellbore before and after treatment with the additive and/or fluid composition, and the like. Methods for measuring these parameters may be used to assess the ability of the enzymes to reduce, decrease, or inactivate sulfur-containing compounds.
  • 'Effective concentration' is defined herein to mean any concentration of the enzymes that may decrease or reduce the amount of sulfur-containing compounds within the fluid composition, a subterranean reservoir wellbore and a downhole fluid recovered therefrom; alternatively, 'effective concentration' is defined herein to mean any amount of the cysteine synthase enzyme and/or the sulfide quinone reductase enzyme that may decrease the amount of sulfur-containing compounds.
  • Samples 1 and 5 were the blanks for each set that do not contain cysteine synthase.
  • Samples 2 and 6 included an O-Acetyl-Serine (OAS) in a concentration of 5 mM, pyridoxal-5'-phosphate (PLP) in an amount of 0.25 mM, and a cysteine synthase enzyme, i.e. an O-Acetyl-Serine Sulfhydrylase (OASS) enzyme, in an amount of 50 ⁇ (about 200 nanograms of enzyme).
  • Samples 3 and 7 included OAS in a concentration of 5 mM, PLP in a concentration of 0.25 mM, and the OASS enzyme in an amount of 50 ⁇ .
  • Samples 4 and 8 included OAS in a concentration of 5 mM, no PLP, and the OASS enzyme in an amount of 50 ⁇ _.
  • An increased absorbance measurement at 560 nm represents an increased amount of cysteine formed from each sample.
  • the reactions treated with the cysteine synthase enzyme showed higher concentrations of cysteine compared to the blanks (samples 1 and 5), indicating that the cysteine was synthesized from the enzyme.
  • the cysteine synthase enzyme used H 2 S or sulfide during the enzymatic reaction to synthesize cysteine. No significant differences in H 2 S reduction (decrease) occurred regardless of whether PLP was present during the enzymatic reaction.
  • each set of samples produced about the same amount of cysteine where the second set produced more cysteine than the first set.
  • Samples 4 and 8 which did not have PLP, produced similar amounts of cysteine indicating that the addition of PLP is optional.
  • the lack of PLP in samples 4 and 8 also indicates that the PLP is optional from the concentrations of H 2 S measured, which was the lowest amount of H2S as compared to the other samples 1-3 and 5-7.
  • Samples 1 and 5 the experiment blanks for each set that did not include the cysteine synthase enzyme, had high amounts (14.5 and 15 mg/L) of H 2 S as compared to at least a 50-60% decrease in H 2 S present in samples 2-4 and 6-8 treated with the cysteine synthase enzyme.
  • FIG. 3 is a graph depicting the effect of reaction components on cysteine synthase activity by detecting the amount of cysteine produced by reacting the completed reaction products with acid ninhydrin and measuring the absorbance with a spectrometer at 560 nm (amino acids reacts with ninhydrin to produce purple color).
  • Sample 1 included 5 mM O-Acetyl serine, 1 mM sulfide, 1 mM DTT, 0.25 mM PLP, and 100mM Tris HCI buffer, pH 7.5; sample 1 did not include the OASS enzyme.
  • Sample 2 included the cysteine synthase (OASS) enzyme in an amount of 50 microliters ⁇ (about 200 nanograms of the enzyme), 5 mM O-Acetyl serine, 1 mM sulfide, 1 mM DTT, 0.25 mM PLP, and 100mM Tris HCI buffer, pH 7.5.
  • Sample 3 included the cysteine synthase (OASS) enzyme in an amount of 50 microliters ⁇ , 5 mM O-Acetyl serine, 1 mM sulfide, and 100mM Tris HCI buffer, pH 7.5; sample 3 did not include dithiothreitol (DTT), nor did sample 3 include PLP.
  • OASS cysteine synthase
  • Sample 4 included the cysteine synthase (OASS) enzyme in an amount of 50 microliters ⁇ , 5 mM O- Acetyl serine, 1 mM sulfide, 0.25 mM PLP, and 100mM Tris HCI buffer, pH 7.5; sample 4 did not include DTT.
  • Sample 5 included the cysteine synthase (OASS) enzyme in an amount of 50 microliters ⁇ , 5 mM O-Acetyl serine, 1 mM sulfide, and 100mM Tris HCI buffer, pH 7.5; sample 5 did not include dithiothreitol (DTT), nor did sample 3 include PLP.
  • OASS cysteine synthase
  • Sample 6 included the cysteine synthase (OASS) enzyme in an amount of 50 microliters ⁇ , 5 mM O- Acetyl serine, 1 mM sulfide, and 100mM Tris HCI buffer, pH 7.5; sample 6 did not include DTT, nor did sample 6 include PLP; however, sample 6 included 50% O-acetylserine OAS. Sample 7 was substantially similar to sample 6, except that sample 7 only included 25% OAS.
  • OASS cysteine synthase
  • sample 2 which included all of the reaction components, formed the largest amount of cysteine.
  • an absence of DTT in the sample may reduce detection of cysteine as the cysteine is oxidized after formation; however, the absence of DTT may not affect the reaction efficiency of the cysteine synthase enzyme.
  • an absence of PLP in the sample may not affect the reaction efficiency of the cysteine synthase enzyme, as the PLP molecule is added to the cysteine synthase enzyme during protein expression.
  • FIG. 4 is a graph depicting the amounts of H 2 S measured in each sample after 4 h.
  • Sample 1 included 5 mM O-Acetyl serine, 1 mM sulfide, 1 mM DTT, 0.25 mM PLP, and 100mM Tris HCI buffer, pH 7.5; sample 1 did not include the cysteine synthase (OASS) enzyme.
  • Sample 2 included the OASS cysteine synthase enzyme in an amount of 50 microliters ⁇ , 5 mM O-Acetyl serine, 1 mM sulfide, 1 mM DTT, 0.25 mM PLP, and 100mM Tris HCI buffer, pH 7.5.
  • Sample 3 included the cysteine synthase (OASS) enzyme in an amount of 50 microliters ⁇ , 5 mM O-Acetyl serine, 1 mM sulfide, and 100mM Tris HCI buffer, pH 7.5; sample 3 did not include dithiothreitol (DTT), nor did sample 3 include PLP.
  • Sample 4 included the cysteine synthase (OASS) enzyme in an amount of 50 microliters ⁇ , 5 mM O-Acetyl serine, 1 mM sulfide, 0.25 mM PLP, and 100mM Tris HCI buffer, pH 7.5; sample 4 did not include DTT.
  • OASS cysteine synthase
  • Sample 5 included the cysteine synthase (OASS) enzyme in an amount of 50 microliters ⁇ , 5 mM O-Acetyl serine, 1 mM sulfide, and 100mM Tris HCI buffer, pH 7.5; sample 5 did not include dithiothreitol (DTT), nor did sample 3 include PLP.
  • Sample 6 included the cysteine synthase (OASS) enzyme in an amount of 50 microliters ⁇ , 5 mM O-Acetyl serine, 1 mM sulfide, and 100mM Tris HCI buffer, pH 7.5; sample 6 did not include DTT, nor did sample 6 include PLP; however, sample 6 included 50% O-acetylserine OAS. Sample 7 was substantially similar to sample 6, except that sample 7 only included 25% OAS.
  • sample 7 had the lowest amount of H 2 S remaining after treatment.
  • the H 2 S concentration was decreased the most in samples 6 and 7, which may be due to more efficient use of OAS by the enzyme in the absence of DTT and PLP.
  • FIG. 5 is a graph depicting the amount of H 2 S present in the head space in four samples measured by gas chromatography (GC). 'Head space' refers to the gaseous volume within each sample.
  • Sample 1 was the blank where no cysteine synthase (OASS) enzyme was added to the sample.
  • Samples 2-4 included 400 mL mM Tris-HCL, pH 7.0, 5 mM cysteine synthase, 1 mM DTT, and 0.025 mM PLP. Samples 2-4 were sparged with 10% H 2 S for two hours to reach an H 2 S concentration of 1500 ppm in the vapor phase.
  • OASS cysteine synthase
  • OASS cysteine synthase
  • FIG. 7 is a graph depicting use of a cysteine synthase enzyme and a sulfide quinone reductase enzyme in sour water.
  • the first set of samples to the far left is sour water without any treatment, which has a sulfide concentration of about 35 ppm. Each sample had a total volume of 100 mL of sour water, and enzyme where noted.
  • the second set of samples includes a sour water sample having a sulfide concentration of about 35 ppm, and the second sample of the second set of samples included the same sour water sample with 2 mL of sulfide quinone reductase enzyme.
  • the third set of samples includes a sour water sample having a sulfide concentration of about 40 ppm, and the second sample of the third set of samples included the same sour water sample treated with 2 mL of cysteine synthase enzyme.
  • the 2 mL of each enzyme was obtained from a crude lysate, which is about 500 ppm of each enzyme.
  • the sulfide quinone reductase and the cysteine synthase enzymes both decrease the amount of sulfide concentration present in the sour water.
  • FIG. 8 is another graph depicting use of a cysteine synthase enzyme and a sulfide quinone reductase enzyme in sour water.
  • the first set of samples to the far left is sour water without any treatment, which has a sulfide concentration of about 1800 ppm. Each sample had a total volume of 100 mL of sour water and enzyme where noted.
  • the second set of samples includes a sour water sample having a sulfide concentration of about 1900 ppm, and the second sample of the second set of samples included the same sour water sample with 2 ml_ of sulfide quinone reductase enzyme.
  • the third set of samples includes a sour water sample having a sulfide concentration of about 1700 ppm, and the second sample of the third set of samples included the same sour water sample treated with 2 ml_ of cysteine synthase enzyme.
  • the 2 ml_ of each enzyme was obtained from a crude lysate, which is about 500 ppm of each enzyme
  • the sulfide quinone reductase and the cysteine synthase enzymes both decrease the amount of sulfide concentration present in the sour water.
  • FIG. 9 is a graph depicting a combination of cysteine synthase enzyme and sulfide quinone reductase enzyme use to decrease a percentage of sodium sulfide in a solution.
  • Eight samples having the same solution and same percentage of sodium sulfide were subjected to various treatment amounts of cysteine synthase enzyme and sulfide quinone reductase enzyme combinations.
  • the solution (in the absence of enzyme) comprised sodium sulfide from a stock solution having 1000 ppm, de-ionized water, 0.05 M Bis Tris buffer having a pH of 7.4, and 0.1 M Tris buffer having a pH of 7.5.
  • the first sample did not include any treatment and had a 100 percent sodium sulfide therein.
  • the second sample included 300 ppm of sulfide quinone reductase enzyme in the absence of cysteine synthase enzyme.
  • the third sample included 60 ppm cysteine synthase and 240 ppm sulfide quinone reductase enzyme.
  • the fourth sample included 120 ppm cysteine synthase and 180 ppm sulfide quinone reductase enzyme.
  • the fifth sample included 180 ppm cysteine synthase and 120 ppm sulfide quinone reductase enzyme.
  • the sixth sample included 240 ppm cysteine synthase and 60 ppm sulfide quinone reductase enzyme.
  • the seventh sample included 270 ppm cysteine synthase and 30 ppm sulfide quinone reductase enzyme.
  • the eighth sample included 300 ppm cysteine synthase in the absence of sulfide quinone reductase enzyme. When both the cysteine synthase enzyme and the sulfide quinone reductase enzyme were used, the enzymes were added at the same time.
  • FIG. 10 is another graph depicting a combination of cysteine synthase enzyme and sulfide quinone reductase enzyme use to decrease a percentage of sulfide in sour refinery water.
  • Six samples having the same solution and same concentration of sulfide were subjected to various treatment amounts of cysteine synthase enzyme and sulfide quinone reductase enzyme combinations.
  • the solution (in the absence of enzyme) comprised sulfide from a sour refinery water having 300 ppm of sulfide.
  • the first sample did not include any treatment and had 100 parts per million (ppm) of sulfide therein.
  • the second sample included 150 ppm of sulfide quinone reductase enzyme and 750 ppm cysteine synthase enzyme.
  • the third sample included 300 ppm of sulfide quinone reductase enzyme and 600 ppm cysteine synthase enzyme.
  • the fourth sample included 600 ppm of sulfide quinone reductase enzyme and 300 ppm cysteine synthase enzyme.
  • the fifth sample included 900 ppm of sulfide quinone reductase enzyme in the absence of any cysteine synthase enzyme.
  • the sixth sample included 900 ppm cysteine synthase enzyme in the absence of any sulfide quinone reductase enzyme.
  • cysteine synthase enzyme 900 ppm cysteine synthase enzyme in the absence of any sulfide quinone reductase enzyme.
  • the present invention may suitably comprise, consist or consist essentially of the elements disclosed and may be practiced in the absence of an element not disclosed.
  • the additive composition for a base fluid such as a drilling fluid, a completion fluid, a production fluid, a servicing fluid, an injection fluid, a refinery fluid, and combinations thereof may consist of or consist essentially of at least one cysteine synthase enzyme that is at least 75% homologous to the cDNA sequence of SEQ ID NO: 1 and at least one sulfide quinone reductase enzyme that is at least 75% homologous to the cDNA sequence of SEQ ID NO:2.
  • the fluid composition may consist of or consist essentially of a base fluid, at least one cysteine synthase enzyme that is at least 75% homologous to the cDNA sequence of SEQ ID NO: 1 , and at least one sulfide quinone reductase enzyme that is at least 75% homologous to the cDNA sequence of SEQ ID NO:2;
  • the base fluid may be or include, but is not limited to a drilling fluid, a completion fluid, a production fluid, a servicing fluid, an injection fluid, a refinery fluid, and combinations thereof.
  • the method may consist of or consist essentially of contacting at least one fluid with at least one cysteine synthase that is at least 75% homologous to the cDNA sequence of SEQ ID NO: 1 and at least one sulfide quinone reductase that is at least 75% homologous to the cDNA sequence of SEQ ID NO:2 in an effective concentration to decrease and/or remove hydrogen sulfide in the fluid(s).

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Microbiology (AREA)
  • Biodiversity & Conservation Biology (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)

Abstract

Selon l'invention, des enzymes cystéine synthase (par exemple des enzymes O-acétyl-L-sérine sulfhydrylase) peuvent être utilisées en combinaison avec des enzymes sulfure-quinone réductase dans des compositions d'addition ou des compositions de fluides. L'invention concerne des méthodes de réduction ou d'élimination du sulfure d'hydrogène des fluides de fond de trou récupérés et/ou du puits de forage du réservoir souterrain duquel les fluides de fond de trou ont été récupérés. La composition de fluides peut comprendre au moins une enzyme cystéine synthase avec au moins une sulfure-quinone réductase, et un fluide de base tel qu'un fluide à base d'eau, un fluide à base organique et leurs combinaisons.
PCT/US2018/023159 2017-03-23 2018-03-19 Enzymes pouvant éliminer les composés sulfureux présents dans les fluides de fond de trou WO2018175330A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US15/467,687 US20170260074A1 (en) 2014-08-07 2017-03-23 Enzymes for removing sulfurous compounds in downhole fluids
US15/467,687 2017-03-23

Publications (1)

Publication Number Publication Date
WO2018175330A1 true WO2018175330A1 (fr) 2018-09-27

Family

ID=63585697

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2018/023159 WO2018175330A1 (fr) 2017-03-23 2018-03-19 Enzymes pouvant éliminer les composés sulfureux présents dans les fluides de fond de trou

Country Status (1)

Country Link
WO (1) WO2018175330A1 (fr)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110056683A1 (en) * 2006-01-31 2011-03-10 Simon Neil Duncum Wellbore fluid comprising a base fluid and a particulate bridging agent
US20110117067A1 (en) * 2006-08-04 2011-05-19 Verenium Corporation Glucanases, Nucleic Acids Encoding Them and Methods for Making and Using Them
WO2012166964A1 (fr) * 2011-06-03 2012-12-06 The Regents Of The University Of California Métabolisme microbien d'oxyanions chlore en tant que contrôle de production de sulfure d'hydrogène biogénique
US20160039697A1 (en) * 2014-08-07 2016-02-11 Baker Hughes Incorporated Method of mitigating hydrogen sulfide or mercaptan contamination with an enzyme based scavenger
US20160160105A1 (en) * 2014-12-04 2016-06-09 Baker Hughes Incorporated Enzymes for removing sulfurous compounds in downhole fluids
US20170260074A1 (en) * 2014-08-07 2017-09-14 Baker Hughes Incorporated Enzymes for removing sulfurous compounds in downhole fluids

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110056683A1 (en) * 2006-01-31 2011-03-10 Simon Neil Duncum Wellbore fluid comprising a base fluid and a particulate bridging agent
US20110117067A1 (en) * 2006-08-04 2011-05-19 Verenium Corporation Glucanases, Nucleic Acids Encoding Them and Methods for Making and Using Them
WO2012166964A1 (fr) * 2011-06-03 2012-12-06 The Regents Of The University Of California Métabolisme microbien d'oxyanions chlore en tant que contrôle de production de sulfure d'hydrogène biogénique
US20160039697A1 (en) * 2014-08-07 2016-02-11 Baker Hughes Incorporated Method of mitigating hydrogen sulfide or mercaptan contamination with an enzyme based scavenger
US20170260074A1 (en) * 2014-08-07 2017-09-14 Baker Hughes Incorporated Enzymes for removing sulfurous compounds in downhole fluids
US20160160105A1 (en) * 2014-12-04 2016-06-09 Baker Hughes Incorporated Enzymes for removing sulfurous compounds in downhole fluids

Similar Documents

Publication Publication Date Title
CA2969548C (fr) Enzymes capables d'eliminer les composes sulfureux contenus dans les fluides de fonds de trous
US10227853B2 (en) Microbial enhanced oil recovery method
US10053610B2 (en) Antifreeze proteins for use in downhole fluids
US20170260074A1 (en) Enzymes for removing sulfurous compounds in downhole fluids
Tian et al. Low dosage hydrate inhibitors (LDHI): advances and developments in flow assurance technology for offshore oil and gas productions
CA2957278C (fr) Procede d'attenuation de contamination par du thiol ou du sulfure d'hydrogene avec un piegeur a base d'enzyme
WO2018175330A1 (fr) Enzymes pouvant éliminer les composés sulfureux présents dans les fluides de fond de trou
US10465105B2 (en) In-situ hydrogen sulfide mitigation
US10947433B2 (en) Proteins for removing sulfurous compounds and/or acidic compounds in downhole fluids
US20170233628A1 (en) Enzyme destabilizers for destabilizing enzymes producing sulfur containing compounds in downhole fluids

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18770588

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18770588

Country of ref document: EP

Kind code of ref document: A1