Flow meter for bitumen froth pipelines

A flow meter device for measuring the flow rate of a viscous fluid through a pipeline having an inner diameter, comprising:

• a conduit comprising an approach section and a venturi section having in series a converging section and a throat section, the converging section of the venturi section being disposed relative to the approach section and the throat section having an inner diameter less than the inner diameter of the approach section;
• a differential pressure measuring device for measuring the pressure difference ΔP between two points that are separate from one another in the flow direction, one point being on the approach section and the other point being on the throat section;
• and
• a heating device for heating the conduit to reduce adherence of the viscous fluid to an inner wall of the conduit as the viscous fluid flows therethrough;
• whereby the pressure difference ΔP correlates to the flow rate of the viscous fluid through the pipeline.

A method for measuring the flow rate of a viscous fluid through a pipeline having an inner diameter, comprising:

• providing a conduit comprising an approach section having an inner diameter less than the inner diameter of the pipeline and a venturi section having in series a converging section and a throat section, the converging section of the venturi section being disposed relative to the approach section and the throat section having an inner diameter less than the inner diameter of the approach section;
• inserting the conduit into the pipeline or between two pieces of pipe comprising the pipeline;
• allowing the viscous fluid to flow through the pipeline and through the approach section of the conduit to increase the velocity of the viscous fluid;
• and
• measuring the pressure difference ΔP between two points that are separate from one another in the flow direction, one point being on the approach section and the other point being on the throat section, to calculate the flow rate in the pipeline.