Reator tubular de alta pressão para produção de PEBD: simulação e análise comparativa da geometria proposta em reator previamente instalado

Abstract

The low density polyethylene (LDPE) is a thermoplastic resin manufactured by high pressure process, operated mainly in tubular reactors. The present scenario is of growing demand for LDPE produced at competitive costs, through high performance and capacity plants, so that the process and the process and product development becomes a key factor for the producers, and process simulators are high importance tools for this purpose. This present work aims to develop mathematically for simulation, an alternative geometry for the high pressure tubular reactor used in the production of LDPE objecting an increase on the conversion of transformed or formed moles in relation to the number of moles initially presents in the reactor, evaluating its predictive capability by comparing its numerical results. The behavior of mass concentration of the polymer formed and total pressure along the length of the reactor were evaluated. Previous work experimental data were used for determining the kinetic model proposed for high pressure tubular continuous-flow reactors for the production of LDPE. It was noted from the simulations that due to the increased volume of the proposed geometry, the modified tubular reactor showed higher yield compared to that without structural modification, since the conversion loss by increasing the pressure gradient over the reactor was lower compared to increased conversion obtained by raising the volume of the reactor. It was developed a financial analysis proving the efficiency of the proposed geometry from an economic balance of the sale price of the product in order to justify the investment with the pressure drop in relation to the obtained product mass concentration.