Abstract:
A digital flowmeter can include a vibratable conduit with a mixture of a liquid and a gas flowing therethrough. A driver can be connected to the conduit and can be operable to impart motion to the conduit where a sensor can also be connected and can be operable to sense the motion of the conduit. A digital transmitter can also be connected to the conduit and can include a void fraction determination system configured to determine a gas void fraction of the mixture, a viscosity determination system configured to determine a viscosity of the liquid in the mixture, and a flow parameter correction system operable to determine a flow parameter associated with the flowing mixture, based on the gas void fraction and the viscosity.
Abstract:
A system for mitigating slugging in the conveyance of hydrocarbons in a flowline includes a first portion of flowline that extends substantially longitudinally along a declining surface. The first flowline portion carries multiphase hydrocarbons. A second portion of flowline extends upward from adjacent the first portion of flowline, and is in fluid communication with the first portion of flowline. A slug-mitigating region is between the first and second portions of flowline so slug-mitigating assembly receives the hydrocarbons from the first portion of flowline and conveys the hydrocarbons to the second portion of flowline. The slug-mitigating region has consecutively joined tubular segments that are each arcuate along a predetermined arcuate angle, with substantially uniform cross-sections. The first portion of flowline can be a subsea flowline extending along a sea floor, and the second portion of flowline can be a riser.
Abstract:
A method of controlling the flow of a multiphase fluid through a pipeline that includes a riser pipe with a choke valve comprises receiving multiple signals dependent on fluid flow properties from a plurality of sensors in the topside area of the riser pipe, analysing the signals to establish a vector of measurement weights, the product of the vector of measurement weights and a corresponding vector of the signal values of a given time being dependent on the severity of a slug flow forming in the system. Further signals dependent on fluid flow properties are received from the plurality of sensors in the topside area of the riser pipe. A set position for the choke valve is then determined from the product of the vector of measurement weights and further values of signals to restrict characteristics of the flow in the topside from moving towards a severely slugging flow regime.
Abstract:
A method of controlling the flow of a multiphase fluid through a pipeline that includes a riser pipe with a choke valve comprises receiving multiple signals dependent on fluid flow properties from a plurality of sensors in the topside area of the riser pipe, analysing the signals to establish a vector of measurement weights, the product of the vector of measurement weights and a corresponding vector of the signal values of a given time being dependent on the severity of a slug flow forming in the system. Further signals dependent on fluid flow properties are received from the plurality of sensors in the topside area of the riser pipe. A set position for the choke valve is then determined from the product of the vector of measurement weights and further values of signals to restrict characteristics of the flow in the topside from moving towards a severely slugging flow regime.
Abstract:
A system for mitigating slugging in the conveyance of hydrocarbons in a flowline includes a first portion of flowline that extends substantially longitudinally along a declining surface. The first flowline portion carries multiphase hydrocarbons. A second portion of flowline extends upward from adjacent the first portion of flowline, and is in fluid communication with the first portion of flowline. A slug-mitigating region is between the first and second portions of flowline so slug-mitigating assembly receives the hydrocarbons from the first portion of flowline and conveys the hydrocarbons to the second portion of flowline. The slug-mitigating region has consecutively joined tubular segments that are each arcuate along a predetermined arcuate angle, with substantially uniform cross-sections. The first portion of flowline can be a subsea flowline extending along a sea floor, and the second portion of flowline can be a riser.