Simulation of Butanol Production through Hydrogenation of Butanal: Effects of Different Reactor Schemes and Operating Conditions

Abstract

The simulation was performed to evaluate the impact of by-passing the second liquid phase reactor in the series due to the catalyst blockage problem leading to the shutdown in a butanol production plant. Butanal hydrogenation for the production of butanol was simulated using the Aspen Plus software package. The process thermodynamics was described by NRTL property model while the kinetic of the main and side reactions was represented by Pseudo-homogeneous model. The attested packed bed reactor model was subsequently used to simulate butanal hydrogenation at different reactor configuration, reactor operating conditions and reactor size. The targeted final total conversion was 99.5% of butanal. The butanal conversion increased with the increase of reaction temperature and residence time. On the other hand, the reactor pressure only affected the performance of the vapour phase reactor but not the liquid phase reactor. Conclusively, the idea of bypassing liquid phase reactor for hydrogenation of butanal in the series could be adopted to achieve the total targeted conversion, provided the plant is allowed to operate at a more severe operating condition. In the modified configuration I, the last reactor should operate at 166.5℃ and 16 bar whereas, in the modified configuration II, the reactor should operate at 285℃ and 30 bar, considering the safety factor.