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Monoethylene glycol (MEG) is used to produce polyester fibers and polyethylene terephthalate resins. It is also utilized in antifreeze, pharmaceuticals, and cosmetics applications. In this research, we consider the development of a novel process plant that produces MEG from ethylene. The proposed ethylene-to-ethylene oxide (EO) plant is integrated with an EO-to-MEG plant to reduce utility costs and recover high-value products. Energy-saving opportunities are analyzed via heat integration tools. Furthermore, a multitube glycol reactor is used in conjunction with a novel MTO catalyst in the ethylene-to-EO reactor. Our results demonstrate that the integrated EO/EG plant produces ethylene glycols with that same purity and product recovery as conventional designs. A comparative economic assessment based on a 200,000 t/y plant indicates that process integration techniques can reduce costs significantly.

Propylene glycol is an important member of the glycol group and is widely used in the industry as a raw material particularly for producing polyester compounds, food additives, and antifreeze. In this research, a novel integrated plant is developed for the production of propylene glycol from shale gas. This integrated approach has the benefit of safer operating conditions because the intermediate propylene oxide, which is explosive, does not need to be stored and transported. Furthermore, there are potential economic benefits from integration. The overall plant is simulated in the Aspen Plus environment, and a variety of process conditions are tested at the steady state to optimize the production of propylene glycol. Heatintegration tools are utilized for energy-saving and capital cost reduction opportunities. A comparative economic assessment based on the existing plant information indicates that the use of process integration techniques has the potential to reduce costs significantly.

As cracker feed around the globe is trending towards lighter feedstocks, butadiene production facilities worldwide are now run at turndown capacities. Models are developed to study how operation at turndown ratios of feed rates affects the purity of 1,3‐butadiene. The optimal solvent‐to‐feed ratio was found to be in the range of 6–7 when the plant is run at normal throughput; however, it is necessary to change the solvent‐to‐feed ratio in the range of 10–11 when the plant is operating at turndown capacity. Dynamic simulations indicate that the effect of fluctuations in the feed flow rate on product purity can be minimized by a ratio controller to change the solvent flow rate and a composition controller to alter the side‐draw flow rate.