Risk level Assessment of the Desalter and Preflash Column of a Nigerian Crude Distillation Unit

Abstract

A study of operability and assessment of the safety level of a crude distillation unit in a Nigerian refinery has been carried out. In a crude distillation unit of a refinery, the desalter and preflash column, as well as their associated pipe works and pumps, are considered to have high-risk factors that can present operability problems and possibly hazardous conditions. Applying the HAZOP methodology, a total of 25 guide words were suitably applied on 4 nodes to study the possible deviations that may occur. The 89 causes of these deviations identified in the study could be classified under human errors and equipment malfunctioning. From the nature of the 46 consequences identified, the plant is likely to experience more of operability problems and less of deadly hazardous scenes. Suitable recommendations that will improve the operability and safety levels of the plant were however presented in the study and presented in tables. If the 61 recommendations given in this study can be incorporated into the design with the few safeguards already present in the original design of the plant, the operability problems of the plant will be greatly minimized and safety level will improve drastically.