There could be three times more heavy oil (<20° API) on earth than conventional oil, of which over 40% has already been produced. Around 80% of this heavy oil is too deep to be recovered via mining and has to be recovered in situ. Historically this has involved heating the oil to reduce the viscosity and improve the flow, but this is costly and produces high levels of greenhouse gas (GHG) emissions. This has led to the development of an extraction technique called CHOPS (cold heavy oil production with sand), in which the oil is pumped to the surface using progressive cavity pumps downhole, without heating. However, the disadvantage of CHOPS production is that large quantities of sand can be produced from these unconsolidated reservoirs. This presents unique challenges in multiphase production.
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