Abstract: This invention relates generally to a separation process in which a multi-component feed stream is introduced into a separation system that operates under solids forming conditions for at least one of the feed stream components. The freezable component, although typically CO.sub.2, H.sub.2 S or another acid gas, can be any component that has the potential for forming solids in the separation system. The multi-component feed stream is introduced into a separation system, at least a portion of which operates under solids forming conditions for at least one component of the feed stream. A vapor stream is withdrawn from an upper region of the separation system and compressed to a higher pressure stream. At least a portion of the compressed stream is cooled and then expanded to a lower pressure to further cool the compressed stream. At least a portion of the expanded stream is returned to the separation system, thereby providing refrigeration to the separation system.

Abstract: A method is disclosed of predicting a characteristic of a fluid-containing physical system such as a reservoir. The physical system is discretized to a plurality of gridcells. For each gridcell, nonlinear governing equations are constructed that are representative of fluid properties for each fluid. The nonlinear terms are linearized to derive linear equations at a current timestep. The linear equations are then solved to determine estimates of the solution. The estimated solution is then improved by a gridcell-by-gridcell computation wherein flows into and out of a particular gridcell are determined using linearized values of nonlinear terms in gridcells adjacent that particular gridcell. The improved solution is used to predict a property of a fluid in the physical system at end of the timestep. These calculation steps are repeated for a plurality of timesteps and the results are used to predict a property of the physical system and the fluids it contains as a function of time.

Abstract: This invention relates to a process for liquefying a gas stream rich in methane and having a pressure above about 3103 kPa (450 psia). The gas stream is expanded to a lower pressure to produce a gas phase and a liquid product having a temperature above about -112.degree. C. (-170.degree. F.) and a pressure sufficient for the liquid product to be at or below its bubble point. The gas phase and the liquid product are then phase separated in a suitable separator, and the liquid product is introduced to a storage means for storage at a temperature above about -112.degree. C. (-170.degree. F.).

Abstract: This invention relates to a process for liquefying a pressurized gas stream rich in methane in which the liquefication of the gas stream occurs in a heat exchanger being cooled by a cascade refrigeration system to produce a methane-rich liquid product having a temperature above about -112.degree. C. (-170.degree. F.). In this process, a pressurized gas stream is introduced into heat exchange contact with a first refrigerant cycle comprising at least one refrigeration stage whereby the temperature of the gas stream is reduced by heat exchange with a first portion of a first refrigerant to produce a cooled gas stream. The cooled gas stream is then introduced into heat exchange contact with a second refrigerant cycle comprising at least one refrigeration stage whereby the temperature of the cooled gas stream is further reduced by heat exchange with a second refrigerant to produce a liquefied methane-rich stream having a temperature above about -112.degree. C. (-170.degree. F.

Abstract: A method is disclosed for treating drilling mud discharged from a well wherein the mud contains drill cuttings and paramagnetic materials such as hematite. The drilling mud is first passed through a high-gradient magnetic separator to separate the paramagnetic materials from the drilling mud. The drilling mud is then passed through a centrifuge separator to remove the drill cuttings from the drilling mud.

Abstract: A water-based well completion and workover fluid is disclosed which has improved rheological and filtration control properties at temperatures up to about 450.degree. F. The composition comprises a saturated brine solution, a sized-salt that is insoluble in the saturated brine solution, and a water-soluble filtration additive comprising a polymer produced from at least two monomers selected from the group consisting of 2-acrylamido-2-methylpropanesulfonate, acrylamide, and 2-vinylpyrrolidone.

Abstract: The current invention is a method for modeling the probability of a drill string becoming stuck within a given time frame and a method for applying the model to a well being drilled to reduce the probability of sticking. The model is constructed by performing canonical discriminant analysis on engineering parameters derived from observations taken in historical wells and creating a canonical space with the resulting canonical functions. Posterior probabilities of sticking are then calculated from the historical observations and mapped into the canonical space. To apply the model to a particular well being drilled, the values of the previously derived engineering parameters are calculated from observations in the well being drilled, multiplied by their corresponding canonical coefficients, and summed to obtain a canonical point representation for drilling in that well. This canonical point representation is then mapped into the canonical space to obtain the probability of sticking.

Abstract: A process for determining an end member age of an illite component in an earth sample which contains a diagenetic illite component and a detrital illite component. As a first step, the sample is separated into a plurality of fractions so that the fractions will have different mean ages of illite. Next, the relative percentage of one of the illite components is determined for each fraction. The mean age of total illite in each fraction is determined using potassium-argon age analysis. The determined relative percentages are then correlated with the determined mean ages to generate a linear relationship. The end member age for each illite component can then be determined by using the linear relationship since zero percent of one of the illite components corresponds to the end member age of the other illite component.

Abstract: A process for dewatering an aqueous fluid containing solids using water-absorbent substances is disclosed. A water-absorbent substance and a body to which the solids will adhere are added to the solids-containing aqueous fluid. The water-absorbent substance absorbs water and the solids coat the solids-adhering body. The water-laden substance may then be separated from the solid-adhering body that is coated with solids, thereby separating the water and the solids.

Abstract: A method for recovering oil from a subterranean formation is disclosed wherein an aqueous surfactant solution is injected into the formation to reduce the mobility of gas in a gas-flooding process. The gas may include hydrocarbon gas, inert gas, carbon dioxide, and steam, or mixtures thereof. The surfactant is represented by the general formula ##STR1## where R is a linear or branched chain alkyl group with n carbon atoms wherein n ranges from about 6 to about 50, except that if the gas is steam n ranges from about 9 to about 50;Ar is a mononuclear or fused ring dinuclear aryl group;Z is an ionic group consisting of --SO.sub.3.sup.- M.sup.+ or --R'SO.sub.3.sup.- M.sup.+ wherein M.sup.+ is a cation and R' is a linear or branched chain alkyl group of from one to about six carbon atoms;x ranges from 0 to about 20; andy ranges from 3 to about 100.

Abstract: A process for manufacturing monosulfonated alkylphenol polyalkylene oxide sulfonates is disclosed. The process produces the monosulfonated alkylphenol polyalkylene oxide sulfonates by a combination of sulfonation to produce a sulfate/sulfonate dianion, followed by a displacement of the sulfate to produce a disulfonate. The process produces a commercially viable disulfonate, which has a wide variety of commercial uses.

Abstract: A process is described for removing contaminants from a contaminant-laden solution of dialkyl ethers of polyethylene glycols (polyether solvent) by mixing the solution with an aqueous base solution. The mixture produces at least two liquid phases of different densities, which are then separated from each other. The lighter liquid phase is predominantly the polyether solvent while the heavier liquid phase is predominantly the aqueous base solution and the contaminants. The process is particularly useful in removing triethylene glycol and other glycol-based dehydration solvents.

Abstract: A drill pipe protector which surrounds and embraces a section of drill pipe. The protector includes at least an outer portion and surface made of an elastomeric material in which a quantity of small, hard particles are interspersed. During drilling operations when the protector is placed in sliding contact with the interior surface of casing in a wellbore, the particles exposed on the protectors surface abrade away rust and other protrusions from the inner surface of the casing to rapidly reduce frictional torque and drag experienced in running the drill string. As particles and elastomer are abraded away, additional particles are exposed. In the preferred embodiment the protector is a sleeve consisting of a pair of semi-cylindrical sections, each having an outer elastomeric layer containing approximately 27% by volume and 43% of the combined weight of substantially spherical glass particles sized in the range of 0.15-0.25 millimeters and having a hardness on the MOH scale of approximately 5.5.

Abstract: The present invention provides Ni (and/or Co) base precipitation hardened alloy compositions having improved resistance to stress corrosion cracking and being comprised of:12-25 wt. % Cr;0-10 wt. % Mo;0-12 wt. % W, with the proviso that Mo+0.5 W is .gtoreq.2 wt. % and .ltoreq.10 wt. % and with the proviso that Cr+Mo+0.5 W is .ltoreq.28 wt. %;2-6 wt. % of one or more of Al, Nb, and Ti;<0.05 wt. % C;<0.05 wt. % O;<0.05 wt. % N; and the balance being Ni (and/or Co) and any incidental impurities,wherein the concentrations of Ni (and/or Co), Cr and Mo (and/or W) are correlated so that their combination represents a point within the area ABCD of FIG. 1 hereof. Preferably, the ratio, expressed in atomic percent, of Al to Nb+Ti is between about 0 and 4.0, preferably between about 0.8 and 1.5, more preferably about 1. In addition, Hf is preferably included in a concentration, expressed in weight percent, of between about 10 (C+O+N) and 30 (C+O+N), more preferably between about 15 (C+O+N) and 20 (C+O+N).

Abstract: An improved method for placing ball sealers (25) onto casing perforations (17) in a deviated wellbore (10) is disclosed. In this invention, a plurality of ball sealers (25) are introduced into the casing and are transported to the perforations at an interface (26) between two immiscible fluids; the first or leading fluid (21) having a density greater than the ball sealers and the second or trailing fluid (24) having a density greater than the ball sealers.

Abstract: Plugging perforations in casing in a wellbore penetrating a subterranean formation using degradale ball sealers. The ball sealer used is composed of a polyester polymer which is substantially insoluble in the wellbore fluid. The polymer degrades in the presence of water at an elevated temperature to form small molecules which are soluble in a fluid in the subterranean formation. After the polymer degrades, the flow through the perforation returns to substantially its initial value.

Abstract: A method and apparatus is disclosed for a marine production riser system. The system includes a series of housing sections linked to form a vertical riser column. The integrity of the riser column is maintained by guidelines extending in tension between a subsea installation and a surface vessel. Each housing section has a plurality of passages extending therethrough. Fluid-handling lines retained within the passages are isolated from current forces by the housing sections. To utilize the invention, the nonbuoyant housing sections are positioned between the guidelines, are loosely banded to the guidelines, and are lowered to form the riser column. Fluid-handling lines are threaded through axially-coinciding passages located in each housing section and continuous throughout the riser column. The fluid-handling lines are connected at the sea floor and surface vessel to complete a fluid carrying system.

Abstract: Ball sealers comprising a solid core coated with a polyurethane elastomer are introduced into a well to seal well perforations and divert fluid therein. In the preferred embodiment the ball sealers are used in a hydrocarbon liquid treating fluid and have a density less than the treating fluid.

Abstract: A fairing for elongated elements is disclosed for reducing current-induced stresses on the elongated element. The fairing is made as a stream-lined shaped body that has a nose portion in which the elongated element is accommodated and a tail portion. The body has a bearing connected to it to provide bearing engagement with the elongated element. A biasing device interconnected with the the bearing accommodates variations in the outer surface of the elongated element to maintain the fairing's longitudinal axis substantially parallel to the longitudinal axis of the elongated element as the fairing rotates around the elongated element. The fairing is particularly adapted for mounting on a marine drilling riser having flotation modules.

Abstract: A piggable fluid swivel comprising a first element on which a second element is rotatably mounted. Grooves in both the first and second elements align to form a continuous flow passage between the elements. Openings are provided through the first and second elements and into the flow passage whereby fluid can enter through one element, flow through at least a portion of the flow passage, and then exit through the other element. A flow barrier means similar to a gate valve is provided on one of the elements and includes a baffle plate that is extendable between an open position and a closed position. In an open position, the elements can be easily assembled and disassembled. In a closed position, the baffle plate blocks backflow in the fluid passage which allows pressure to build behind any pig that may become stuck in the flow passage to free the pig and carry it from the swivel. The swivel may be coaxially stacked to provide a multiline piggable fluid swivel.