Study on 1,3-Butadiene Production Issues Arising with the Increasing Trend of Lighter Feedstock

1, 3-butadiene is used in the production of various materials and chemicals for applications in a wide range of industries. The majority of 1,3- butadiene is produced from steam cracking processes. However, the sustained production of 1,3-butadiene is facing big challenges as the cracking feedstock around the globe is trending towards lighter feedstocks, which not only causes a decrease in the butadiene supply, but also forces various butadiene facilities to run at high turndown capacities.

In this paper, two relevant issues will be addressed. First, the optimal operating strategy has been studied for an existing 1, 3-butadiene process operated at a high turndown ratio. Both steady-state and dynamic process models have been developed for the virtual examination. The simulation results show that the optimal solvent to feed ratio is in the range of 6-7 when the plant is running at normal throughput; however, its necessary change the solvent to feed ratio in the range 10-11 when the plant is operating at its turndown capacity. Dynamic simulations also indicate that the effect of fluctuations in feed flowrate on product purity can be minimized via the use of ratio controller to change the solvent flowrate and a composition controller to change the side-draw flowrate. Next, potential bio-feedstock and technologies to make up the shortage of current 1,3-butadiene supplies have been studied. Three different routes that utilize biomasses to produce 1,3-butadiene and associated co-products ethylene and propylene from lignin are explored, where relevant process simulation models have been developed. The study shows that all three technological routes are all feasible and might be considered by the olefin industry. It also suggests that the comprehensive utilization of all olefin products (ethylene, propylene, and 1,3-butadiene) from biomasses based on process system integration might be a promising and profitable solution to deal with 1,3-butadiene shortfall issues in current olefin plants.