Multi-phase fluid sampling method and apparatus

An apparatus for obtaining a compositional analysis is of a homogeneous sample of a multi-phase pressurized fluid stream flowing through a pipeline, where the fluid stream includes a hydrocarbon gas as a major component and a minor component consisting of one or more hydrocarbon liquids and water mixed with the gas, the apparatus comprising:

• a. injection means for adding a predetermined amount of one or more surface active agents to the fluid stream;
• b. means for mixing the one or more surface active agents with the components of the fluid stream in a mixing zone to form a uniform foam composition in the pipeline;
• c. a sampling probe located in a sampling zone in the pipeline downstream of the mixing zone for removing a portion of the foam composition from the pipeline;
• d. a sampling conduit on the exterior of the pipeline in fluid communication with the probe;
• e. sample removal means for withdrawing a predetermined volume of the foam composition from the exterior sampling conduit;
• and
• f. analytical means for identifying the hydrocarbon and water components of the foam sample.

An apparatus for providing a homogeneous sample of a multi-phase pressurized fluid stream flowing through a pipeline, where the fluid stream includes a hydrocarbon gas as a major component and one or more hydrocarbon liquids and water mixed with the gas, the apparatus comprising:

• a. injection means for adding a predetermined amount of one or more surface active agents to the fluid stream;
• b. means for mixing the one or more surface active agents with the components of the fluid stream in a mixing zone to form a uniform foam composition in the pipeline;
• c. a sampling probe located in a sampling zone in the pipeline downstream of the mixing zone for removing a portion of the foam composition from the pipeline;
• d. a sampling conduit on the exterior of the pipeline in fluid communication with the probe;
• and
• e. sample removal means for withdrawing a predetermined volume of the foam composition from the exterior sampling conduit.

Apparatus for creating a homogeneous gas-liquid mixture for sampling comprising:

• an injection zone including injection means having a discharge port in fluid communication with a moving a stream of gas-liquid mixture contained in a pipeline for injecting a foam-generating surfactant agent into the gas-liquid stream;
• a downstream mixing zone that includes mixing means for mixing the surfactant and the gas-liquid stream to induce a uniform foam composition;
• and
• a sampling zone downstream of the mixing zone that includes sampling means for removing a sample of the foam composition from the stream in the pipe.