Absorption mechanism-based approach for synthesis of refinery desulfurization solvent network

Processing of sourer crude oil increases the desulfurization solvent circulation and energy consumption for solvent regeneration. In this work, synthesis of desulfurization solvent network based on mechanism model is proposed to overcome limitations of simplified models in traditional mass integration. A superstructure is presented for desulfurization solvent network where the input and the output of each desulfurization unit are correlated. Such a correlation is realized via an absorption mechanism model for methyldiethanolamine desulfurization. The mathematical models are formulated taking the desulfurization targets as constraints, instead of fixed flowrates, contaminant concentrations, or contaminant loads in traditional methods. A solution strategy combining stochastic and deterministic algorithms is proposed to solve the problems effectively. Finally, this approach is tested on a refinery case considering three scenarios. The solvent regeneration cost can be decreased by over 16.42%. Besides, the comparative results indicate that this mechanism-based method is more reliable than the traditional methods.