Provided herein are drilling muds, including water-based drilling muds. The components of the drilling muds are a degradable fluid loss additive, for example, synthetic degradable nanoparticles, a clay mineral, for example, a smectite, and a base fluid, for example, water. Also provide are methods for preventing leak-off during a drilling operation and for automatically cleaning-up filter cake after completion of a drilling process both of which utilize the drilling muds and water-based drilling muds.

A system and method of determining a density of a drilling fluid in a wellbore. The system includes a drill string in the wellbore, the drill string including a downhole rotor. A drilling fluid flowing through the drill string in the wellbore causes the downhole rotor to rotate relative to the drill string. A brake is configured to apply a first brake torque to the downhole rotor to place the downhole rotor in a first state. A torque measurement system is configured to determine the applied first brake torque. A rotor speed measurement system is configured to measure a first downhole rotor speed of the downhole rotor having the drilling fluid flowing therethrough with the downhole rotor in the first state. A processor is configured to determine a density of the drilling fluid from the measured first downhole rotor speed, and the determined applied first brake torque.

The present disclosure a leak-proof lost-circulation control water-based drilling fluid composition and preparation method and use thereof.

A method of servicing a wellbore penetrating a subterranean formation, the method including placing a wellbore servicing fluid into the wellbore proximate a permeable zone. The wellbore servicing fluid comprises a base fluid and from about 3 wt. % to about 25 wt. % by total weight of the wellbore servicing fluid of a particulate material. The particulate material comprises palm kernel shells.

Various embodiments provide methods and systems for providing fluid lighteners for use in downhole wells. The fluid lighteners may include one or more viscosifiers, one or more aphron generators, and a location-specific non-emulsifying surfactant.

In accordance with one or more embodiments of the present disclosure, a drilling fluid may include a base fluid and one or more formaldehyde-based resins. The drilling fluid may further comprise one or more water-soluble acid catalyst precursors or the reaction products of such water-soluble acid catalyst precursors. The base fluid may include an aqueous or non-aqueous solution. The present disclosure also describes sealed subterranean petroleum formations that include such drilling fluids and methods for sealing subterranean wellbores by utilizing such drilling fluids.

The present invention relates to a riser system in the form of a pumped riser (1), i.e. a riser (1) having an outlet (6) from the riser (1) at a depth below the surface (S) of a body of water, where the outlet (6) is coupled to a return pump (7) to return fluid from the riser (1) to the surface (S), and various operational methods to facilitate greater versatility when performing hydrocarbon drilling related operations. The arrangement also comprises a sealing element (15, 16) to seal an annulus (5) of the riser (1), and a by-pass (17) around the sealing element (15, 16). Various methods makes it possible to switch between open mode and closed mode, and vice versa, monitoring leakage across the sealing element (15, 16), as well as performing other operations exploiting the advantages of the two different modes.

In a method for quantifying a volumetric flow rate of a flow of drilling mud in a floating structure for subsoil drilling, a flowmeter and a detection device are provided on a floating structure for subsoil drilling. The flowmeter generates a flow signal. The detection device generates a heave signal representative of a vertical heave of the floating structure. A processor transforms the flow signal into a first spectrum in the frequency domain and the heave signal into a second spectrum in the frequency domain. The processor compares the first spectrum with the second spectrum, obtaining a resultant spectrum. The processor transforms the resultant spectrum into a resultant signal in the time domain. The processor determines a mean value of the flow signal, adds the resultant signal to the mean value, obtaining a quantification of a flow of drilling mud in the floating structure.

In a method for quantifying a volumetric flow rate of a flow of drilling mud in a floating structure for subsoil drilling, a flowmeter and a detection device are provided on a floating structure for subsoil drilling. The flowmeter generates a flow signal. The detection device generates a heave signal representative of a vertical heave of the floating structure. A processor transforms the flow signal into a first spectrum in the frequency domain and the heave signal into a second spectrum in the frequency domain. The processor compares the first spectrum with the second spectrum, obtaining a resultant spectrum. The processor transforms the resultant spectrum into a resultant signal in the time domain. The processor determines a mean value of the flow signal, adds the resultant signal to the mean value, obtaining a quantification of a flow of drilling mud in the floating structure.

In accordance with one or more embodiments of the present disclosure, a drilling fluid may include a base fluid, one or more formaldehyde-based resins, and one or more water-soluble acid catalysts. The base fluid may include an aqueous or non-aqueous solution. The one or more water-soluble acid catalysts may be present in an amount sufficient to reduce the pH of the drilling fluid to less than or equal to 6. The present disclosure also describes sealed subterranean petroleum formations that include such drilling fluids and methods for sealing subterranean wellbores by utilizing such drilling fluids.