Abstract: A catalyst for use in a Fischer-Tropsch synthesis reaction which comprises cobalt supported on alumina, in which: the catalyst average particle size is in the range 20 to 100 ?m; the specific surface area of the impregnated and calcined catalyst particles is greater than 80 m2/g; the average pore size of the impregnated and calcined catalyst is at least 90 ? (9 nm); and the pore volume of the impregnated and calcined catalyst is greater than 0.35 cm3/g.

Abstract: A method of controlling the annular pressure in a well during a well construction operation. The operation comprises pumping a fluid down a tubing located within the well and extracting the fluid that flows back through an annulus within said well and surrounding the tubing. The method comprises defining a set pressure pref, determining a desired extraction flow rate qc of fluid from said annulus in dependence upon the set pressure pref and a pumped flow rate into the annulus, and configuring an extraction path to achieve said desired extraction flow rate.

Abstract: A method is disclosed for reflection time shift matching a first and a second set of seismic reflection data (10,30) comprising first and second seismic reflection traces (1,3) with series of generally corresponding seismic reflections (11,31). The second set of seismic data (30) comprises at least one laterally extending series (40) of new seismic events (4) not present in the first set of seismic data (10). Reflection time shifts (22) are calculated as required for matching seismic reflections (31) of the second reflection traces (3) of the second seismic reflection data (30) with corresponding seismic reflections (11) of the first reflection traces (1). The calculation of the time shifts (22) are made by calculating coefficients of basis function estimates such as Legendre polynomials in order to save calculation effort.

Abstract: The present invention provides a method for inhibiting scale formation within a hydrocarbon producing system (e.g. a subterranean formation), said method comprising contacting said system with a clay mineral, an organosilane and a scale inhibitor.

Abstract: Method for laying a pipeline onto a seabed from a lay barge, the pipeline having an inner corrosion proof metallic cladding that is closely fitted with metallic contact to an outer pipe material that is less corrosion proof. The method includes reeling a section of the pipeline onto a pipe laying drum, while an overpressure of 5-25 bar is maintained within the section by a pressurized fluid inside the section, b) joining a further pipeline section to the section already reeled onto the pipe laying drum, while the pipeline is motionless without mechanical movement, as the overpressure can he relieved as long as the sections are without mechanical movement, c) applying an overpressure of 5-25 bar within the sections and the further section is reeled onto the pipe laying drum, d) and joining several sections together and reeling the joined sections onto one or several pipe laying drums by repeating step b) and c) until the predetermined pipeline length is achieved.

Abstract: The present invention provides a method of inhibiting formation of solid hydrates in a conduit used to contain a flowing, water-containing hydrocarbon, which method comprises introducing into said hydrocarbon in said conduit a gas which raises the pressure threshold for hydrate formation for said water-containing hydrocarbon, said gas being introduced in a manner which causes it to travel along at least part of said conduit in the direction of hydrocarbon flow.

Abstract: A method of assessing a hydrocarbon source rock candidate uses seismic data for a region of the Earth. The data are analysed to determine the presence, thickness and lateral extent of candidate source rock based on the knowledge of the seismic behaviour of hydrocarbon source rocks. An estimate is provided of the organic content of the candidate source rock from acoustic impedance. An estimate of the hydrocarbon generation potential of the candidate source rock is then provided from the thickness and lateral extent of the candidate source rock and from the estimate of the organic content.

Abstract: A method of well construction or treatment comprising the introduction of a settable cement that contains pulverulent aplite down a borehole is provided, together with a cement composition comprising at least 30% by weight of cement pulverulent aplite on a dry solid basis.

Abstract: An axial gas thrust bearing for rotors in rotating machinery includes at least one radial disk, integral with or fastened to the rotor and one fixed seal facing each disk or two fixed seals positioned to surround each disk, lower portions of the seals being situated at a distance from the rotor to allow the inflow of compressed fluid passing in the gap between the respective disk and seals, thereby combining the properties of a balance piston and thrust bearing disk.

Abstract: The present invention provides a process for simultaneously extracting and upgrading a heavy hydrocarbon mixture, said process comprising: i) injecting supercritical or near-supercritical CO2 at a temperature of around the critical temperature and a pressure of from around the critical pressure into a heavy hydrocarbon deposit; and ii) removing a stream of CO2 from the deposit, which stream is charged with a hydrocarbon mixture having a lower average molecular weight than that of the heavy hydrocarbon deposit, wherein the removed CO2 is optionally recovered and either recycled for subsequent re-injection or injected for long-term sub-surface storage.

Abstract: An expandable pipe section, intended to be joined with a corresponding pipe section for use in connection with a well casing of a production well for hydrocarbons, where the pipe section is configured to be screwed on or off an adjoining expandable pipe section, the pipe section at one end being provided with a male end having externally arranged threads and where the adjoining expandable pipe section is provided with a correspondingly shaped female end having corresponding internal threads. The distance between adjacent threads at their widest point is less than the maximum width of a thread. Those parts of the pipe being provided with threads are provided with at least two step wise arranged parts with a cylindrical surface being coaxially arranged with the pipe wall(s).

Abstract: A method of protecting a hydrocarbon conduit during a period of reduced hydrocarbon flow is disclosed, where nitrogen is introduced into the conduit at a pressure of 1 to 350 bar g and at a rate of (1.5 to 35)A kg/sec (where A is the internal cross sectional area of the conduit in square meters) for a period of t hours where t=(p×d)/n where d is the length in km of the conduit from the nitrogen introduction location and n is 10 to 400.

Abstract: There is disclosed a method of performing a controlled source electromagnetic survey, which includes in one embodiment deploying a receiver and an electric dipole source. The source defines a dipole axis. An electromagnetic field is transmitted from the electric dipole source. First and second horizontal components of an electromagnetic field response are detected using the receiver. A vertical component of the electromagnetic field response is then estimated using the detected first and second horizontal components of the electromagnetic field response.

Abstract: The equipment for drilling and reinforcing a borehole of a well comprises a drill pipe string carrying a drill tool at its lowermost end and a downhole treatment device held on the drill pipe string for applying a liner of polymer material at the surface of the borehole. The polymer material is a fusible and/or curable material dissolved and/or emulsified and/or dispersed in drilling fluid or mud circulated through the drill pipe string and an annulus between the drill pipe string and the wall of the borehole. The treatment device is adapted to concentrate energy for fusing and/or curing the polymer material contained in the drilling fluid in a limited space at the vicinity of the wall of the borehole. The treatment device thus focuses its energy in the vicinity of the wall and allows a continuous reinforcing of the borehole simultaneously while drilling.

Abstract: A pressure joint is provided for use with a floating installation (1) that is connected to a stiff riser (3, 12). A low pressure slip joint (5) connects the installation (1) to the stiff riser (3, 12). A telescopic assembly (13, 14) fitted with a high pressure seal (15) is arranged to be fitted within the low pressure slip joint (5) when in a non-extended configuration, such that normal operation of the low pressure slip joint (5) is not impeded.

Abstract: The apparatus for evaluating a wellbore while drilling includes a logging toolheld on a drill string and is adapted to obtain data from the wellbore while moving the drill string including the logging tool uphole and out of the wellbore. The logging tool includes a memory for storing obtained data and an on-board power supply battery. A computer being positioned at a surface level of the wellbore is adapted to obtain the data from the memory when the logging tool is also positioned at the surface level. The logging tool is adapted to perform a minimum power-consuming sleep mode with a data obtaining and storing function being disabled and the computer is adapted to transmit a wake-up signal downhole to enable the data obtaining and storing function of the logging tool just prior to tripping out the drill string from the wellbore. The wake-up signal preferably is a mud pulse signal sent through the drilling fluid used when drilling the wellbore.

Abstract: A catalyst composition comprising cobalt as an active catalytic element and a lesser amount of nickel as a promoter supported on a metal oxide support. The support may comprise alumina, silica, silica-alumina, zeolite, zirconia, magnesia or titania. The amount of nickel is preferably less than 50 wt %, relative to the amount of cobalt.

Abstract: A single stage process for desulfurization and ring opening of a sulphur containing hydrocarbon feedstock comprising: contacting said feedstock with hydrogen and a catalyst at a pressure of less than 100 bars wherein said catalyst comprises (I) a combination of molecular sieves consisting of at least one zeolite which has a faujasite structure and at least one fibrous zeolite which comprises essentially non-crossing one-dimensional channels and (II) a composition comprising at least one metal selected from group VIB of the periodic table and at least one metal from group VIII.

Abstract: Subsurface hydrocarbon reservoir-sized structures are detected or monitored by ambient noise tomography. Interface wave data are recorded for interface waves excited by seismic ambient noise. The data are recorded simultaneously at pairs of locations with the locations of each pair being spaced by less than or equal to a wavelength at the frequencies of interest. The recorded data are processed (3-7) by tomography to obtain group-velocity and/or phase-velocity tomograms, which are inverted to obtain seismic parameters values, such as seismic velocity. The seismic parameters may then be used to form a geological model (8) of a subsurface region of interest.

Abstract: The present invention provides a method for recovering hydrocarbons from a sub-surface reservoir having present therein a wellbore in which a production conduit and an injection conduit are located, said method comprising injecting a heating fluid into the reservoir via said injection conduit, characterised in that said heating fluid is released via a plurality of discrete permeable sections (injection sections) located along the length of the injection conduit and produced hydrocarbons are collected via a plurality of discrete permeable sections (production sections) located along the length of the production conduit.