Investigation of propane addition to the feed stream of a commercial ethane thermal cracker as supplementary feedstock

• Published in: Journal of the Taiwan Institute of Chemical Engineers 2017-12, Vol.81, p.1-13
• Main Authors: Feli, Zohreh, Darvishi, Ali, Bakhtyari, Ali, Rahimpour, Mohammad Reza, Raeissi, Sona
• Format: Article
• Language: English
• Subjects: Cracking; Ethane; Ethylene; Plant; Propane; Pyrolysis furnace
• ISSN: 1876-1070; 1876-1089
• DOI: 10.1016/j.jtice.2017.10.025

•Investigate the strategies and solutions feed shift in a commercial plant steam cracking unit.•A pseudo-dynamic model for ethane and propane co-cracking.•Validation of calculations against real plant available plant data.•Investigation of effect of feed shift on the run length of cracking furnace.•Longer run length was obtained in the cases with higher propane concentration in the feed stream. With the aim of investigating the solutions of ethane shortage in a commercial ethylene plant, addition of propane as supplementary feedstock and increasing steam to hydrocarbon ratio were proposed as possible strategies. These strategies were proposed to compensate for the ethane shortage in the thermal cracking unit of the commercial plant. Run length, ethylene yield, and propylene yield were considered as the determining factors to appraise the strategies. The major contribution of present work would be the investigation of effect of feed shift on the run length of the steam cracker. Regarding this, five different cases were investigated in real plant condition. To include all the aspects of process, a mathematical model with reasonable assumptions was developed and then validated against the real plant data. Based on the obtained results, increasing propane concentration leads to increase in propylene yield and decrease in ethylene yield. Besides, run length of process was obtained to be longer in the cases with higher propane content in the feed stream. [Display omitted]