Evaluation of Different Levels of Retrofit and Optimization of Cold-Section of BIPC Olefin Plant

In this paper, retrofit and optimization of the cold-end section of 6th Olefin plant of BIPC is investigated. Having considered the importance of a simultaneous design through the elements (distillation columns, heat exchanger network and refrigeration cycles), three levels of modifications are suggested. The best operating column parameters along with available refrigeration cycles, a modification of refrigeration levels along with the same core process and heat exchanger network and finally a comprehensive and simultaneous retrofit scheme are evaluated for this case study. Having compared the results, one can conclude that simultaneous optimization of operating column parameters, refrigeration cycles and the associated heat exchanger network leads to higher efficiency showing 23.9% of energy saving with an investment payback of 3 months.