(122i) Crude Assays - the Distillation

The Distillation

Andrew W. Sloley

DGI

Bellingham, WA, USA

Since the first oil well was drilled in Titusville, PA in 1859 the refining industry has continuously worked to cope with the fundamental question of ‘What is that crude worth?’ The value of a specific crude varies with its processing costs and the values of its possible products. Over time, the crude assay has been developed to answer this question. The elements of a crude assay include a mix of vaporization characteristics and properties of possible products that might be made from the crude. The key points for the first processing unit in the oil refinery, the Crude Distillation Unit, revolve around the distillation curve and properties related to corrosion and fouling.

This paper reviews the development of the distillation curve. Topics include the current status of distillation curve methods and their interpretation and use. Near-future developments, and their possible use are also discussed. Discussion include how distillation curve use interacts with prediction of molecular weights from density or other methods.