(85e) Ethylene Production Using Oxidative Dehydrogenation: Effects of Combined Membrane-Based & Alternative Distillation Separation Technologies on Process Safety & Economics

Previous work from this group utilized a HYSYS simulator to predict the performance of an ethylene oxidative dehydrogenation (ODH) production facility using alternative diluents and membrane separation technology not currently used in the standard industrial process [1-3]. An ODH process system has been previously modeled with ethane being fed along with air into a reactor with simultaneous mixing with pure methane to lower the product gas temperature. The methane feed was later separated from the other product gases and eventually fed into a recycle stream. This process was fairly expensive due to the use of a demethanizer within the process recycle stream. Safety and operational improvements for the ODH process was another aspect of this analysis that yielded interesting results. By the inclusion of storage vessels before and after the ODH reactor, the reactor unit can operate even in the event of an upstream or downstream failure, resulting in less downtime for the process.

The current work investigated the development of membrane-based separation in combination with alternative distillation technologies, such as bottom-flash, heat-pump assisted and low-temperature distillation, for the production of ethylene for the oxidative dehydrogenation (ODH) reaction of ethane using a HYSYS simulator with MEMCAL extension software in concert with economic and safety analyses using Dow Fire & Explosion Index, Mond Index and the Inherent Safety Index methods. The application of combinations of polymer-membrane separation with alternative distillation technologies were simulated and evaluated individually and in-tandem with membrane separation. The effects of alternative diluents, process flammability issues, and economic analysis results will also be discussed.

Literature Cited:

1.Maffia GJ, Gaffney AM, Mason OM, Techno-economic analysis of oxidative dehydrogenation options, Top. Catal. (2016), http://dx.doi.org/10.1007/ s11244-016-0677-9 (2016, August 16).

2.Baroi C, Gaffney AM, Fushimi R, Process economics and safety considerations for the oxidative dehydrogenation of ethane using M1 catalyst, Catal. Today (2017), http://dx.doi.org/10.1016/j.cattod.2017.05.041 R (2017, May 11).

3.Gao, Y., Neal, L., Ding, D., Wu, W., Baroi, C., Gaffney, A.M., Li, F., Recent Advances in Intensified Ethylene Production: A Review, ACS Catalysis (2019), http://10.1021/acscatal.9b02922 (2019, August 12).