Namit Tripathi

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.

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.