ASTM D2892 for distillation of crude petroleum (15-Theoretical Plate Column)
4. Summary of Test Method
4.1 A weighed sample of 1 to 30 L of stabilized crude petroleum is distilled to a maximum temperature of 400°C AET in a fractionating column having an efficiency at total reflux of at least 14, but not greater than 18, theoretical plates.

4.2 A reflux ratio of 5:1 is maintained at all operating pressures, except that at the lowest operating pressures between 0.674 and 0.27 kPa (5 and 2 mm Hg), a reflux ratio of 2:1 is optional. In cooperative testing or in cases of dispute, the stages of low pressure, the reflux ratios, and the temperatures of cut points must be mutually agreed upon by the interested parties prior to beginning the distillation.

4.3 Observations of temperature, pressure, and other variables are recorded at intervals and at the end of each cut or fraction.

4.4 The mass and density of each cut or fraction are obtained. Distillation yields by mass are calculated from the mass of all fractions, including liquefied gas cut and the residue. Distillation yields by volume of all fractions and the residue at 15°C are calculated from mass and density.

4.5 From these data the TBP curves in mass or volume %, or both, versus AET are drawn.

5. Significance and Use
5.1 This test method is one of a number of tests conducted on a crude oil to determine its value. It provides an estimate of the yields of fractions of various boiling ranges and is therefore valuable in technical discussions of a commercial nature.

5.2 This test method corresponds to the standard laboratory distillation efficiency referred to as 15/5. The fractions produced can be analyzed as produced or combined to produce samples for analytical studies, engineering, and product quality evaluations. The preparation and evaluation of such blends is not part of this test method.

5.3 This test method can be used as an analytical tool for examination of other petroleum mixtures with the exception of LPG, very light naphthas, and mixtures with initial boiling points above 400°C.