Abstract: Disclosed is an experimental device and method for solubility determination of methane in oil-based drilling fluid, comprising a pressure-resistant gas chamber and an equilibrium still both arranged in a constant-temperature oil bath heating oven, a gas booster pump, and a vacuum system used for vacuuming the pressure-resistant gas chamber and the equilibrium still, and a data acquisition device for collecting temperature and pressure signals; the gas booster pump is connected to drive air source inlet, a gas check valve is arranged on the pipe between the pressure-resistant gas chamber and the gas booster pump that is also connected with a high-pressure gas cylinder, the equilibrium still is divided into a dissolution equilibrium chamber at the top and a hydraulic oil chamber at the bottom by a high-pressure dynamic seal structure, the dissolution equilibrium chamber is connected to a liquid inlet funnel through the fourth globe valve.

Abstract: The invention discloses a circulating system and a method for continuous downhole cooling of high-temperature drilling fluid. The circulating system includes a cooling water tank, a cooling water injection pump, a plurality of U-shaped pipes, a liquid nitrogen cooling tank, a spiral pipe, a cooling water return pump and a return pipeline. The U-shaped pipe is fixed in an unsealed bond cement gap between outer and inner casings, and two ends are respectively connected with output end of the cooling water injection pump and the spiral pipe. The spiral pipe is disposed in the liquid nitrogen cooling tank; input and output ends of the cooling water return pump are respectively connected with the spiral pipe and the return pipeline; one end of the return pipeline is disposed in the cooling water tank; input end of the cooling water injection pump is connected with the cooling water tank by a pipe.

Abstract: The invention discloses a dynamic simulation method of circulating temperature variation in RMR subsea pump mud-lift drilling system, including steps: obtaining operating parameters, environmental parameters, well structure parameters and thermal parameters of target well; establishing temperature control equation of drill string in seawater section, temperature control equation of drill string in formation section, temperature control equation of annulus in formation section, and temperature control equation of return pipe in seawater section; re-determining initial and boundary conditions; discretizing spatial structure of the whole system with inner node method; discretizing control equations on corresponding nodes; substituting corresponding parameters into discrete expressions to obtain circulating temperature in drill string of seawater section, circulating temperature in drill string of formation section, circulating temperature in annulus of formation section, and circulating temperature in return pip

Abstract: The invention discloses a dynamic simulation method of circulating temperature variation in RMR subsea pump mud-lift drilling system, including steps: obtaining operating parameters, environmental parameters, well structure parameters and thermal parameters of target well; establishing temperature control equation of drill string in seawater section, temperature control equation of drill string in formation section, temperature control equation of annulus in formation section, and temperature control equation of return pipe in seawater section; re-determining initial and boundary conditions; discretizing spatial structure of the whole system with inner node method; discretizing control equations on corresponding nodes; substituting corresponding parameters into discrete expressions to obtain circulating temperature in drill string of seawater section, circulating temperature in drill string of formation section, circulating temperature in annulus of formation section, and circulating temperature in return pip

Abstract: The invention discloses a circulating system and a method for continuous downhole cooling of high-temperature drilling fluid. The circulating system includes a cooling water tank, a cooling water injection pump, a plurality of U-shaped pipes, a liquid nitrogen cooling tank, a spiral pipe, a cooling water return pump and a return pipeline. The U-shaped pipe is fixed in an unsealed bond cement gap between outer and inner casings, and two ends are respectively connected with output end of the cooling water injection pump and the spiral pipe. The spiral pipe is disposed in the liquid nitrogen cooling tank; input and output ends of the cooling water return pump are respectively connected with the spiral pipe and the return pipeline; one end of the return pipeline is disposed in the cooling water tank; input end of the cooling water injection pump is connected with the cooling water tank by a pipe.