The ethylene unit (EU-1544) at the Port Arthur Plant of Chevron Phillips Chemical Company LP (Chevron Phillips Chemical) was originally commissioned in 1970 with a major unit expansion in 1997. A cyclohexane unit and a third-party cumene unit are also located at the site. Due to rising energy costs, significant focus has been placed on reducing energy consumption.
In 2005, Chevron Phillips Chemical committed to performing process audits as part of each ethylene units' turnaround cycle. For the 2008 turnaround, the first process audit was performed for EU-1544 in 2006. The goal of the pre-turnaround process audit was to identify operational changes and projects to improve the energy performance of EU-1544.
The work from the 2006 process audit became the starting point and the data set for KBC's Strategic Energy Review (SER). KBC reviews the entire site when benchmarking, performing operational reviews, and Pinch Analysis for the SER. Results from the SER include a ProSteam model of the steam system and a Road Map of identified projects for implementation.
Following the turnaround, a process audit was done to accomplish three major goals: to identify and value the remaining gaps at “clean unit conditions,” to establish baseline performance for a clean unit, and to confirm benefits from projects and from maintenance work done during the turnaround.
This paper will discuss the methods, implementation, and benefits of performing process audits to achieve greater energy efficiency at EU-1544.