Low Field NMR Water Cut Metering

摘要

We have developed a new on line water cut meter usinglow field Nuclear Magnetic Resonance (NMR) technology.This instrument is designed for use on heavy oil systemswhere conventional instruments experience difficulties.We present laboratory and field data for application of lowfield NMR to water cut measurements of bitumen/watermixtures. Data from successful field tests near Cold Lake,Alberta, Canada, shows that the instrument is capable ofmaking water cut measurements over a wide range of fluidtypes and temperatures. We have successfully measured fluidstreams with temperatures ranging from 60 to 150 degreesCentigrade and with water cut ranging from 40 to 95 percent.The instrument is capable of functioning accurately over awide range of emulsions and/or foams and through significantvariations of water salinity.The current application is for water cut measurements ona well site. However, the instrument can be applied in anysystem where heavy oil, bitumen, water, gas and solid systemsmay be encountered. It can be used for water cut and/or forthree phase (oil/water/gas) volume fraction measurements.The instrument is equally capable of performing well sitemonitoring for regulatory/reconciliation purposes, forcharacterizing produced fluids, in separation, pipelining andupgrading processes for process control and for quality testing.