Hydrate plugged a pipeline with gas flowing through water at elevated pressure, low ambient temperature, treated with a hydrate promoter and spiked with propane. Predictive methods accurately showed where the dominant blockage formed. During blowdown from 660 to 12 psia, hydrate redeposited in vent orifice. Field measured flow velocity reached 74 ft/s, wall shear at hydrate deposition reached 78 Pa. Hydrate deposited at that shear reduced the orifice area approximately by half, which extended the time to depressurize, affecting process safety. Blowdown time formula matched state-of-the-art multiphase transient simulation. Shear stress should be a common parameter reported by researchers in flow assurance. All content contained within this webinar is copyrighted by Dr. Taras Makogon and its use and/or reproduction outside the portal requires express permission from Dr. Taras Makogon.
