Patent ID: 8512550

Claim:
A method for the determination of optimal operation for a given crude oil feedstream of a refinery pipestill by determining a virtual assay of said crude oil feed comprising: a) feeding a crude oil feedstream into said refinery pipestill wherein said crude oil feedstream is separated into boiling range fractions and determining the yields of the boiling range fractions. b) performing a virtual assay of said crude oil feedstream by the steps in c, d and e, c) determining an IR spectrum of said crude oil feedstream, d) fitting said IR spectrum to a linear combination of known IR spectra in a database to determine the coefficients of the linear combination, wherein the database includes IR spectra of reference crude oils whose boiling range fraction yields are known, e) determining the boiling point fractions yields of said crude oil feedstream from the coefficients of the linear combination and the boiling range fraction yields of the reference crudes, f) comparing the predicted boiling range fraction yields with the actual boiling range fraction yields from the pipestill to determine differences between these fraction yields, g) relating said difference between the fraction yields with the optimal operation of the refinery pipestill for the crude oil feedstream.