Full cycle dynamic optimisation maintaining the operation margin of acetylene hydrogenation fixed-bed reactor

Abstract

Abstract In an acetylene hydrogenation reactor, the slowly falling catalyst activity affects ethylene plant performance in an operating cycle. To maximize the integral economic benefit in a regeneration cycle or achieve the longest regeneration cycle, the full cycle operation optimisation must be a long time-scale dynamic optimisation for which the method of control vector parameterization is adopted. Because of various uncertain disturbances, some distances must be reserved for process constraints and the desired effect of full cycle optimisation is hardly fully achieved. Thus, based on the strictly slowly-time-varying catalyst deactivation model, the operation margin consumption is estimated. Furthermore, a modified full cycle operation optimisation strategy is presented which takes the operation margin consumption as additional constraints. To obtain the maximum integral economic benefit or the longest regeneration cycle, we present a realizable full cycle optimized operation plan that considers the sufficient operation space reserved for uncertain disturbances.