The Model 871 Oil and Water Retort Kit is used to determine the quantity of liquids and solids in a drilling fluid. In a retort test, a measured sample of fluid is placed in a cup and heated until the liquid components have been vaporized. The vapors are passed through a condenser and collected in a graduated cylinder or centrifuge tube that has been calibrated to record the volume of the condensed liquids at 20°C. The distillate is read directly as volume percent of the solids sample's original volume. Suspended and dissolved solids are determined by subtracting these from 100 percent of the initial sample. For fresh-water fluids, the relative amount of barite and clay can be estimated. Corrections must be made for salt in the calculation for solids content by volume.
The Oil and Water Retort provides a simple, direct field method for determining the percent by volume of oil and water in samples in drilling mud or in core samples of the formation. The Retort has been found to be especially useful in determining the oil content of emulsion muds. Retorts are available in 115 and 230 volt models.