Abstract: The invention relates to a hydrocarbon synthesis process in the presence of a catalyst that comprises a substrate, at least one metal of group VIII that comprises metal particles, preferably cobalt, characterized in that the group VIII metal particles of the catalyst are deposited on the substrate in the form of aggregates.

Abstract: The invention concerns a process for optimal operation of a slurry bubble column containing a suspension of solid particles in a liquid, characterized in that a gas phase containing the reactant(s) required for the production of the desired products is injected in the form of bubbles close to the lower extremity of said reactor and at least a portion of the liquid fraction and optionally of the solid fraction of said suspension is recirculated, drawn off from close to one extremity of said reactor and reintroduced close to the other extremity of said reactor, with a liquid flow rate U.sub.1 in the reactor which is at least equal to and preferably greater than the sedimentation rate U.sub.s of the solid particles. The invention also concerns an apparatus for optimal operation of the process. Finally, the invention concerns the use of the process and apparatus in the Fischer-Tropsch synthesis.

Abstract: Integral joint for connecting two pipes, in which from the annular edge of the female pipe an internal flaring with decreasing cross-section extends, which gets engaged, with interference, with a corresponding external counter-flaring provided on the end portion of the male pipe nearby the overhanging back shoulder of the latter, in order to create another tight, all-metal sealing with interference, additionally to the other tight sealing already existing at the front end of said end portion of the male pipe.

Abstract: Process for the consolidation of sand in a well which produces fluids, particularly oil and/or gas, comprising the following steps:1) optional preflush with an aqueous solution of inorganic salts, preferably KCl;2) injection into the formation of a consolidating agent essentially consisting of an aqueous solution of sodium silicate in water;3) flushing with an inert gas, preferably nitrogen, of the formation treated in step (2) until the excess consolidating agent and water injected in step (2) have been removed;4) subsequent introduction into the formation thus treated of an aqueous solution of an acid having a pKa at 25.degree. C. of between 3 and 10, preferably selected from ammonium chloride and acetic acid.

Abstract: Process for recovering and moving highly viscous petroleum derivatives by the formation of aqueous dispersions in the presence of water with a salinity of more than 0.6% by weight, particularly from 1 to 15% by weight, with the use of hydrosoluble sulfonated dispersants, said process being characterized in that the above sulfonated dispersants have a content of the high molecular weight fraction, determined by SEC analysis (Size Exclusion Chromatography), of more than 4%.

Abstract: Method for the continuous up-dating of a bidimensional and tridimensional seismic image in depth in real time during the drilling of a well by using seismic velocity information comprising the initial definition of a velocity model and the subsequent re-iterative modification of this initial velocity model by integrating the geophysical data taken on the surface with the geological domain of the subsurface data obtained directly during the drilling of the well.

Abstract: The present invention relates to a device used for the direct measurement of the permeability of rock fragments coming directly from the drilling of an oil well and commonly called cuttings, consisting of a hollow cylindrical body (c) that presents an inlet hole for the fluid (i), a thread for closing it (h) and a hydraulic seal (g) in which is placed the sample holder disk (d) which rests on the seal (g) and is overlapped by a porous sintered steel septum (e) on which a closing plug (f) is situated with an outlet hole for the fluid (i') and the same is also provided with a thread (h') to enable it to close on the body (c).The device can be used to obtain, directly on site, the measurement of permeability along the whole length of an oil well.

Abstract: Process for the optimum operation of a slurry bubble column reactor in the presence of a gas phase and a liquid phase, particularly for the Fischer-Tropsch reaction, characterized in that:1) the process is carried out in a number of stages in series of .gtoreq.2;2) the flow conditions of the gas phase and liquid phase containing the solids are essentially plug flow conditions, with a gas rate of between 3 cm/s and 200 cm/s and a liquid rate of between 0 and 10 cm/s;3) the concentration of solids in each stage is essentially constant and equal for each single stage, and is between 5 and 50% (vol./vol.).

Abstract: Method for measuring the propagation velocities of ultrasonic acoustic waves through rock fragments which includes the steps of (a) introducing the fragment in a coupling fluid between a pair of piezoelectric transducers capable of generating highly damped ultrasonic acoustic waves; (b) passing highly damped ultrasonic acoustic waves through the fragment, said waves being generated by a pulse generator with a pulse width varying from 0.1 .mu.s to 20 .mu.s; (c) visualizing the obtained electric signals by an oscilloscope with a resolution of at least 10.sup.-2 .mu.s; and (d) measuring the transit time of the waves themselves. The ultrasonic acoustic waves may be compressional or shear waves. In one embodiment the coupling fluid has a viscosity varying be 200 and 800 poises.

Abstract: Process for the dissolution of asphaltene sediments in oil wells which consists in introducing a solubilizing composition for the above asphaltenes into the oil wells, characterized in that the solubilizing composition comprises:(a) a basically hydrocarbon fraction consisting of at least 70%, preferably at least 80% by weight, of aromatic and alkyl aromatic hydrocarbons, the alkyl group being from C.sub.1 to C.sub.4 ;(b) a fraction basically consisting of quinoline and isoquinoline as such or alkyl substituted, preferably as such, the alkyl group being from C.sub.1 to C.sub.4 ; the weight ratio between fraction (a) and (b) being from 97.5/2.5 to 75/25, preferably from 97/3 to 90/10.

Abstract: An anti-seizure protection for a threaded joint or sleeve, particularly suitable for the petroleum sector, comprises a first film layer of a copper-zinc alloy anchored to the threads of the joint and a second film layer of lead anchored to the first layer. The anchoring is preferably achieved by ionic deposition.

Abstract: Disclosed is a process for preparing aqueous, clay-based muds, not aggressive to layer clays, which process comprises a first step in which clay is treated with an aqueous solution containing the necessary amount of dispersant to fluidify the mud; a second step, of separation of so treated clay from the aqueous solution containing any not adsorbed dispersant, and finally, a step of re-dispersion of so treated clay in water, in order to formulate the mud.

Abstract: Procedure for evaluating the parameter of actual K.sub.a total friction of a shouldered threaded connection which includes:a) making up the connection applying a general make-up torque and observing the corresponding torque/turn diagram;b) subsequently breaking out the connection observing the corresponding torque/turn diagram;c) calculating the actual K.sub.a of the connection with an appropriate equation.

Abstract: Process for recovering and moving highly viscous petroleum products, by the use of aqueous dispersions in the presence of sulphonate dispersers prepared:a) by increasing the molecular weight of steam cracking fuel oil by its oligomerization in the presence of a catalyst selected from BF.sub.3 and complexes thereof with strong acids;b) sulphonating the compound obtained from step (a) by reaction with a sulphonating agent, preferably SO.sub.3 ;c) neutralizing the sulphonate obtained from step (b) by treatment with hydroxides selected from the hydroxides of alkaline or earth alkaline metals or ammonium.

Abstract: Process for recovering and moving highly viscous petroleum products as aqueous dispersions in the presence of a sulphonate dispersing agent selected from the sulphonates of alkaline or earth-alkaline metals or ammonium of indene-cumarone sulphonate resins.

Abstract: Aqueous drilling muds are disclosed which contain, as fluidifier agent, one or more complexes, which may be either pre-formed or produced in situ, selected from:tetravalent zirconium and one or more organic acids, or their salts, having the general formula (I) ##STR1## wherein R.sub.1 and R.sub.2, which may be the same or different from each other, represent --H, --COOH, --CH.sub.3, --CH.sub.2 COOH, --CH(OH)COOH;aluminum citrate.

Abstract: A process for preparing vertical seismic profiles (VSP) by bore drilling using, as the seismic source, the vibrations generated by the drilling bit. A cross-correlation between the bit signal and the signals collected by seismic geophone lines, is determined in which the bit signal is processed by arranging a plurality of several types of detectors on the bore drilling facility. A plurality of traces are recorded, in which the signal/noise components have different characteristics. These can be separated by means introducing filter functions by operating either on their Fourier Transforms or on the basis of their statistic distribution.

Abstract: Quick joint for rapid, tight-seal connection of pipes, in which from the end of the female hollow body an internal flaring with decreasing cross-section extends, suitable for getting engaged, with interference, with a corresponding external counter-flaring provided on the male hollow body in the neary of the overhanging shoulder of the latter which, on its one side, cooperates with the sleeve of the joint and, on its other side, cooperates with said end of said female hollow body; from the end of said male hollow body furthermore a second external flaring with decreasing cross-section extends, suitable for getting engaged, with interference, with a counter-flaring provided inside the interior of said female hollow body in the nearby of an internal shoulder for said male body.Also preferred embodiments are disclosed.

Abstract: A cementitious composition for oil well cementation able to prevent fluid migration comprises water, hydraulic cement, surfactant or organic dispersant, and carbon black.

Abstract: Process for recovering and causing highly viscous petroleum products to flow by means of an aqueous dispersion of the petroleum product, in which the dispersant is selected from alkali metal or ammonium salts of organic sulfonates having the following properties: (A) sulfur content of at least 10%; (B) water solubility at 20.degree. C. of at least 15% by weight; (C) decrease in water surface tension, at a concentration of 1% by weight, not higher than 10%.