Method and apparatus for treating pressurized drilling fluid returns from a well

摘要

A method and apparatus for treating pressurized drilling fluid returns from a well having a returns outlet. The method comprises the steps of providing a primary separator for selectively separating solid, liquid and gas components of the drilling fluid returns where the primary separator has an input for introducing drilling fluid returns thereto; providing a secondary separator for selectively separating at least a portion of a gas component in the drilling fluid returns where the secondary separator has an input for introducing drilling fluid returns thereto; connecting the input of the primary separator and the input of the secondary separator to the returns outlet of the well such that the input of the secondary separator is connected to the well returns outlet upstream of the input of the primary separator; providing a control to regulate the flow of drilling fluid returns through the input of the primary and secondary separators; monitoring the flow of the gas component of the drilling fluid returns expelled from the primary separator; and, in response to changes in the flow of gas expelled from the primary separator, operating the control to regulate the flow of drilling fluid returns through the primary and secondary separators to maintain the flow of gas expelled from the primary separator within predetermined parameters.