Abstract: A method for drilling a well below a body of water as disclosed which includes injecting into the well, at a depth below the water surface, a liquid having a lower density than a density of a drilling mud producing a mixture of drilling mud and low-density liquid in the well. The mixture of drilling mud and low-density liquid is withdrawn from an upper end of the well. The drilling mud and the low-density liquid are separated, with at least a portion of the separated low-density liquid returned to the depth below the water surface and at least a portion of the separated drilling mud returned to an upper end of the drill string.

Abstract: A method for drilling a well below a body of water as disclosed which includes injecting into the well, at a depth below the water surface, a liquid having a lower density than a density of a drilling mud producing a mixture of drilling mud and low-density liquid in the well. The mixture of drilling mud and low-density liquid is withdrawn from an upper end of the well. The drilling mud and the low-density liquid are separated, with at least a portion of the separated low-density liquid returned to the depth below the water surface and at least a portion of the separated drilling mud returned to an upper end of the drill string.

Abstract: A method for drilling a well below a body of water as disclosed which includes injecting into the well, at a depth below the water surface, a liquid having a lower density than a density of a drilling mud producing a mixture of drilling mud and low-density liquid in the well. The mixture of drilling mud and low-density liquid is withdrawn from an upper end of the well. The drilling mud and the low-density liquid are separated, with at least a portion of the separated low-density liquid returned to the depth below the water surface and at least a portion of the separated drilling mud returned to an upper end of the drill string.

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 novel method of determining the probability that a planned drilling path will collide with an existing wellbore is disclosed. The method utilizes available uncertainty information to determine a probability for each of a plurality of segments of the planned drilling path that a projection of the segment onto a plane will intersect a projection of a corresponding segment of the existing wellbore onto the plane. The method of this invention then determines the net probability for each segment of the planned drilling path that the segment will intersect the corresponding segment of the existing wellbore by taking into account the effect of constraints imposed on each segment, by adjacent segments. The probability that the planned drilling path will intersect the existing wellbore is determined by adding together all of the net probabilities.

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 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 of drilling and cementing a well using a novel drilling fluid convertible in place by the extrinsic application of heat into a settable cement slurry and composition therefor. The novel drilling fluid comprises an aqueous drilling mud containing in intimate admixture therewith cement and a thermally deactivatable deflocculant which prevents the cement from setting while the fluid is being used as a drilling mud. The method comprises drilling a well with a rotary bit through which the novel drilling fluid is circulated; suspending a casing in the well; removing the fluid from inside the casing; and applying sufficient extrinsic heat to the fluid in place in the annulus of the well to deactivate the deflocculant, thereby converting the fluid in place into a settable cement slurry.

Abstract: A spacer comprising the water-in-oil emulsion portion of a shear-thickening well control fluid is used to separate drilling mud from the shear-thickening fluid in the drill pipe in the well bore to avoid premature thickening of the shear thickening fluid in the drill pipe. The shear-thickening well control fluid comprises a water-in-oil emulsion in which is dispersed granular particles of hydratable, water expandable clay.

Abstract: A process for separating liquid hydrocarbons from a wastewater using acoustic energy below cavitation is disclosed. The wastewater containing the residual hydrocarbons is introduced into a vessel which has at least two groups of acoustic transducers attached to it. Acoustic energy is applied to the fluid at an intensity below cavitation level and sufficient to induce at least one standing wave in the fluid. The liquid hydrocarbons are allowed to coalesce within the vessel to a coalesced droplet size of about 20 microns. These coalesced hydrocarbons are then separated from the wastewater.