A method for determining a wax appearance temperature of a fluid includes
obtaining nuclear magnetic resonance (NMR) measurements of the fluid at a
plurality of temperatures; deriving a NMR parameter from each of the NMR
measurements; and determining the wax appearance temperature by analyzing
the NMR parameter as a function of temperature. An apparatus for
detecting wax appearance in a fluid includes a sample cell for holding a
fluid for nuclear magnetic resonance (NMR) measurements at a plurality of
temperatures; a temperature measuring device disposed proximate the
sample cell; a magnet for polarizing molecules in the fluid in the sample
cell; at least one radiofrequency (RF) coil for generating pulses of
magnetic field and for detecting NMR signals; and circuitry for
controlling and measuring the temperature of the fluid in the sample cell
and for obtaining NMR measurements.