(44b) Petro II Ethylene Plant APC Applications

The Petro 2 ethylene plant produces polymer-grade ethylene, chemical-grade propylene, and by-products from an ethane/propane feedstock. Many APC applications were commissioned several years ago, including MPC controllers for each of the five furnaces plus controllers for hot and cold side fractionation. Over the years, the performance and benefits of the APC applications have deteriorated and some controllers were no longer used. After the plant turnaround in 2007, a new project was launched to revive the APC applications. Matrikon software tools were purchased for monitoring and tuning PID loops, for monitoring APC controllers, and for automated step testing and modeling. These tools were utilized to upgrade APC models for the C2 Splitter, C3 Fractionator, Demethanizer, Deethanizer, and the five furnaces. The APC applications have been successfully re-commissioned and performance monitoring tools indicate high online service factors with improved performance. Severity controls have also been re-commissioned with new models and the addition of feedback updates from online analyzers. The APC applications allow the plant to maximize production when market conditions are favourable and to reduce energy costs.