OPTIMIZED CRUDE DISTILLATION UNIT (CDU) OPERATIONS WITH ADVANCED PROCESS CONTROL

摘要

A process analytics project on a crude distillation unit (CDU) demonstrates the use and advantages of FT-NIR as a multi-stream, multi-property analytical method for CDU optimization. CDU advanced process control is often implemented using a traditional chemical engineering approach through multiple control loops, heat / mass balances and pressure / temperature / flow measurements. Where side-draw quality estimates are needed it is common to use inferential models, based on empirical correlations between the process parameters and the reconciled True Boiling Point (TBP) curve of the nominal crude feed assay. Process FTIR using a fibre-optic based configuration with separate heated sample flow-cell cabinets for each process stream allows for rapid multi-property, multi-stream, accurate, real-time product quality data to be fed at an appropriate data-rate to the CDU on-line optimizer. The challenges associated with crude distillation and a case study of a typical implementation using an on-line process FTIR will be presented.