application #1
multi-phase oil sands tailings
In this application, a three-phase fluid (oil sands tailings) requires a significant pressure drop. Attempting to reduce this pressure within a single stage can trigger cavitation, erosion, and undesirable alterations to the fluid’s properties. Preserving the fluid’s key characteristics is essential for maximizing water and land reclamation efforts.
To mitigate these risks, the system was thoroughly analyzed, and specialized equipment and design protocols were accounted for. Due to the inherent complexity, customizing the solution to the required conditions was the most effective approach. The resulting two-stage pressure reduction method is described below:
First Stage: A Control Valve with custom-engineered trim applies the initial pressure drop while minimizing fluid shear.
Second Stage: An eccentric Orifice Plate, positioned downstream of the control valve, further reduces the pressure to the target setpoint.
For similar multi-phase applications with dispersed solids, accurately predicting shear rates during flow through valves and orifice plates is crucial. Because these fluids frequently exhibit non-Newtonian behaviour, Computational Fluid Dynamics (CFD) simulations are particularly useful.
A 3-phase CFD analysis illustrates how valve trim design influences shear rate in high-pressure drop applications.
However, accurate rheological data and mathematical models remain essential for predicting shear-sensitive behaviours. With the right inputs and techniques, CFD can help optimize valve trim designs, evaluate shear rates, and analyze turbulence and velocity gradients, ultimately enhancing flow component performance.