Orthogonal collocation based‐optimization of fouling resistance for industrial low‐density polyethylene production in a tubular reactor.

In tubular reactors, fouling issues are caused due to two reasons. One is the heating–cooling prerequisite, and the other is the exothermic nature of the low‐density polyethylene (LDPE) polymerization process. These issues must be considered while optimizing LDPE production to provide maximum productivity and a safe operation. However, it is not a simple process because the conversion of the monomer (XM) is generally related to significant profits. This conversion might be performed at high reaction temperatures, resulting in fouling formation. Therefore, in this research, a study of dynamic optimization to find the most efficient production of LDPE in the presence of fouling resistance (Rf) restrictions is conducted. An Rf is employed as a measure of fouling. To establish the highest reactor RfRfmax=50cm2sK/cal$$ \left({R}_{f_{\mathrm{max}}}=50\ \mathrm{cm}2\ \mathrm{s}\ \mathrm{K}/\mathrm{cal}\right) $$, this study employs variations in the heat transfer coefficient (U) calculated from industry data. This dynamic optimization study addresses the optimization challenges using dynopt coded programming based on orthogonal collocation (OC) and sequential quadratic programming methodologies. Beforehand, the LDPE model is validated with industrial data. This study evaluates three possibilities to determine the most optimum reactor performance. The most optimum reactor output is determined from the constrained maximum conversion, which gave 32.15% conversion, while the Rf$$ {R}_f $$was effectively met at 47.37cm2 s K/cal. [ABSTRACT FROM AUTHOR]