| To fulfill the ever-increasing demand of energy saving and emission reduction, optimization technologies become more and more important, and broadly applied in chemical industries, e.g., productivity maximization, cost minimization, process retrofit, and flexibility enhancement. In this dissertation, three aspects of optimization technologies are discussed for energy saving and emission reduction: conceptual design, dynamic simulation, and production scheduling.;A novel methodology for the design of a flexible water-reuse network has been developed, which simultaneously considers the integration of multiple Water-Reuse Network Designs (WRND)s and network switch control for different manufacturing purposes. An MILP (Mixed Integer Linear Programming) based model is developed to identify simultaneously the best retrofit design and hoist schedule to obtain the maximum productivity under a fixed retrofit budget.;Dynamic modeling and simulations of two start-up designs with different recycling stream patterns associated with three start-up operating strategies with different time arrangement are performed. From this the most desirable start-up solution for a chemical plant can be identified, considering energy usage saving and flare minimization.;Energy consumption optimization is achieved by improving the configuration design of the integrated Cracked Gas Compression-Depropanization (CGC-DeC3) system. One innovative design is conducted under the consideration of introducing part of the heavier stream from early stages of compression section directly into the fractionation section to reduce the work in following compression, the CGC Stripper operation load, and the heat exchangers' duty.;A rigorous model for a front-end Depropanization system has been developed, based on which, the operating performances of High Pressure and Low Pressure Depropanizers under various scenarios (e.g., various temperature and pressure changes) have been predicted and studied. |
