Prediction of surface gas concentrations in drilling fluid
AssigneeSchlumberger Technology Corporation
InventorsIvan FORNASIER, Emilie COLOMBEL, Jerome BREVIERE
Life of this patent
Estimating the term…
Abstract
A method for estimating surface concentrations of gas in a drilling fluid in use in a drilling rig includes measuring gas-out or gas-in concentrations while drilling a wellbore and processing the gas-out measurements or the gas-in measurements with a calibrated model to estimate corresponding gas-in concentrations or gas-out concentrations.
Claims20
A method for estimating surface concentrations of gas in a drilling fluid in use in a drilling rig, the method comprising:
- measuring first concentrations of the gas in the drilling fluid as it exits a wellbore (gas-out) or second concentrations of the gas in the drilling fluid as it is pumped downhole (gas-in) while drilling a wellbore;
- and
- estimating the gas-in concentrations or the gas-out concentrations by evaluating the gas-out measurements or the gas-in measurements with a calibrated model.
A surface system configured for use on a drilling rig, the surface system comprising:
- a gas measurement module configured to measure first concentrations of a gas in drilling fluid as it exits a wellbore (gas-out) and second concentrations of the gas in the drilling fluid as it is pumped downhole (gas-in) while drilling;
- and
- a processor configured to:
- receive gas-out and gas-in measurements made while drilling a first section of a subterranean wellbore;
- evaluate the gas-out and gas-in measurements with a model to generate a calibrated model;
- receive gas-out measurements or gas-in measurements made while drilling a second section of a subterranean wellbore;
- and
- estimate the gas-in concentrations or the gas-out concentrations by evaluating the gas-out measurements or the gas-in measurements with the calibrated model.
A method for estimating surface concentrations of gas in drilling fluid while drilling a wellbore, the method comprising:
- drilling the wellbore at a set of drilling conditions;
- evaluating the set of drilling conditions with a parameter model to obtain a calibrated degassing model including a set of calibrated degassing model parameters;
- measuring first concentrations of a gas in the drilling fluid as it exits the wellbore (gas-out) or second concentrations of the gas in the drilling fluid as it is pumped downhole (gas-in) while drilling;
- and
- estimating the gas-in concentrations or the gas-out concentrations by evaluating the gas-out measurements or the gas-in measurements with the calibrated model.
Dependencies are inferred from the claim text.