Patent application number | Description | Published |
20090023616 | AQUEOUS FRACTURING FLUID - The invention concerns an aqueous viscoelastic fracturing fluid for use in the recovery of hydrocarbons. According to the invention, the fluid comprises a cleavable viscoelastic surfactant and a hydrophobically-modified polymer, wherein the cleavable surfactant comprises a head group and a hydrophobic tail of at least 18 carbon atoms connected through a degradable acetal, amide, ether or ester bond and wherein the concentration of the hydrophobically-modified polymer is comprised between its overlap concentration c* and its entanglement concentration c | 01-22-2009 |
20090075845 | Degradable Polymers for Wellbore Fluids and Processes - A viscosifying agent for wellbore fluids is described including a polymer polymerized using at least two pre-polymers “A” and “B”, the polymer being capable of essentially fully degrading into soluble fragments after the initiation of a breaking process. | 03-19-2009 |
20090097358 | Seismic Monitoring Of Heavy Oil - A method of monitoring heavy oil recovery in a hydrocarbon reservoir including the steps of obtaining a set of acoustic signals; deriving from the obtained signals a velocity model including shear and compressional velocities for at least a section of the reservoir; defining a relation relating shear and compressional velocities to at least one material parameter of the heavy oil; performing a reservoir treatment process; obtaining an in-situ or post-treatment set of acoustic signals; and deriving from the in-situ or post-treatment set of acoustic signals shear and compressional velocities and the at least one material parameter using the relation. | 04-16-2009 |
20100167967 | WELLBORE TREATMENT WITH HYDROCARBON-RESPONSIVE FLUID CONTAINING OLIGOMERIC VISCOELASTIC SURFACTANT - A treatment of a subterranean formation which contains a hydrocarbon-bearing zone, is carried out using a hydrocarbon-responsive fluid thickened with an oligomeric surfactant consisting of from 2 to 8_linked surfactant monomer subunits. The process of treatment comprises
| 07-01-2010 |
20100276150 | PROVISION OF VISCOUS COMPOSITIONS BELOW GROUND - A thickened aqueous composition is delivered to a subterranean location accessible via a wellbore by steps of i. providing a biphasic aqueous mixture comprising two aqueous solutions which, at surface temperature and pressure, are able to co-exist as separate aqueous phases in contact with each other, ii. pumping said biphasic aqueous system down the wellbore to the subterranean location, and iii. converting the biphasic mixture below ground so that its phases combine into a single aqueous phase which is more viscous than the biphasic mixture. The two phases of the aqueous biphasic mixture contain dissolved solutes which segregate between the two phases such that at least one first solute is present at a greater concentration in the first aqueous phase than in the second aqueous phase while at least one second solute is present at a greater concentration in the second aqueous phase than in the first aqueous phase. The solute in the first phase may be a thickening polymer or other thickening material such as viscoelastic surfactant. The solute in the second phase may be a different polymer, surfactant or salt. Conversion to a single phase may be carried out in various ways including dilution, change in pH, change in salinity, increase in temperature and adsorption of one solute onto formation rock. | 11-04-2010 |
20100307744 | USE OF ENCAPSULATED CHEMICAL DURING FRACTURING - A process for hydraulic fracturing of a subterranean reservoir formation penetrated by a wellbore includes pumping a fracturing fluid or other aqueous fluid which is an aqueous suspension of particles which each comprise an oilfield chemical distributed within an encapsulating matrix of water-insoluble carrier_material from the surface via the wellbore and into the reservoir. The encapsulating matrix is chosen so as to provide a delayed release of the oilfield chemical from the particles into surrounding fluid, such that oilfield chemical is liberated from the particles after they have entered the fracture. The encapsulating matrix may be a polymer which is at least partially amorphous, with a glass transition temperature below the reservoir temperature. | 12-09-2010 |
20100307745 | USE OF ENCAPSULATED TRACERS - A process of making observations of a subterranean reservoir penetrated by a wellbore uses distinguishable sets of tracer particles and comprises steps of:
| 12-09-2010 |
20110036577 | MANIPULATION OF FLOW UNDERGROUND - Solid material required at a subterranean location is supplied from the surface suspended in a carrier liquid and agglomerated below ground by means of a binding liquid. Agglomeration is achieved by arranging that the binding liquid and the particulate solid are similar to each other but opposite to the carrier liquid in hydrophilic/hydrophobic character. The solid and the binding liquid may both be hydrophobic while the carrier liquid is hydrophilic, or vice versa. The solid may be hydrophobically surface modified to render it hydrophobic. The binding liquid may be provided as a precursor which converts to the binding liquid below ground to trigger agglomeration after arrival at the subterranean location. | 02-17-2011 |
20110152136 | SOLVENT ASSISTED OIL RECOVERY - The recovery of oil from a reservoir is assisted by injecting a diluent into the reservoir formation to reduce the viscosity of the crude oil. This diluent is a mixture of a material which is an asphaltene precipitant, especially supercritical carbon dioxide, and a more polar material which comprises at least one aliphatic compound which includes at least one of a cycloaliphatic ring, an olefinic unsaturation, an ester or ether group. The inclusion of such an aliphatic compound which is more polar than the asphaltene precipitant reduces asphaltene precipitation and can enhance the efficiency of oil recovery when the precipitant is by supercritical carbon dioxide. | 06-23-2011 |
20110172924 | FORECASTING ASPHALTIC PRECIPITATION - The magnitude of asphaltic precipitation when injecting a viscosity reducing diluent into a reservoir formation, notably to assist oil recovery therefrom, is forecast by (i) determining a relationship between asphaltic precipitation and a solubility parameter for the diluted oil, and then (ii) utilizing that relationship to forecast the magnitude of asphaltic precipitation when injecting a predetermined viscosity reducing diluent into the formation. Making this forecast may be followed by injecting a viscosity reducing diluent into the formation to assist oil recovery. The diluent may in particular be supercritical carbon dioxide or other asphaltene precipitant mixed with a more polar material in proportions designed by forecasting asphaltic precipitation by candidate materials in possible proportions. | 07-14-2011 |
20120103615 | VISCOUS WELLBORE FLUIDS - A wellbore fluid contains a viscosifying polymer in which portions of the polymer are connected through formation of an inclusion complex involving cucurbituril 8 (i.e. CB[8]) as host molecule. The fluid contains guest molecules with first and second guest groups covalently attached wherein at least one of the guest molecules comprises a polymer chain. The CB [8] host and the guest molecules attach together through reception of first and second guest groups within CB[8] host cavities, thereby connecting polymer chains together as a larger, supramolecular polymer and enhancing viscosity of the fluid. Polymer molecules may be synthetic polymers and guest groups may be attached to monomers before polymerization. Alternatively guest groups may be attached to existing polymers which may be polysaccharide. | 05-03-2012 |
20130161003 | PROPPANT PLACEMENT - Embodiments of hydraulic fracturing methods disclosed herein use fine mesh proppant. In one embodiment the method is used to fracture a low permeability formation. In one embodiment the method uses flocculation to improve conductivity of a fracture. In one embodiment fluid flow through the fine mesh proppant in the fracture creates a network of connected channels to improve the fracture conductivity. | 06-27-2013 |
20140076815 | SEPARATION OF OIL DROPLETS FROM WATER - A treatment process for an aqueous phase which contains oil droplets, possibly of 10-50 nm diameter, in aqueous flow from a hydrocyclone separator, comprises bringing the water into contact with a surface subdivided into areas of differing surface energy and affinity for oil and such that when the surface is submerged in an aqueous phase, oil droplets adhere to it with an apparent contact angle in a range from 90 to 150 degrees. Areas of the surface may reduce their affinity for oil in response to an external stimulus causing controlled release of droplets adhering to the surface. The process may be used to remove oil droplets from water produced by an oil or gas well, after downhole oil water separation or after production at a at a well head, or used to coalesce droplets in such water to a larger size to enable conventional separation. | 03-20-2014 |