Análise, simulação e otimização do processo de hidrodealquilação de tolueno (HDA)

Abstract

Benzene production is quite strong in the chemical industry, with revenue estimated at US$ 69 billion for 2021 according to a market study by Ceresana (2014). This aromatic compound is an intermediate substance, used as a raw material for the manufacture of other chemical products, mainly ethylbenzene, cumene and cyclohexane. In view of its market importance, this work performs the analysis, simulation and optimization of the toluene hydrodealkylation process (HDA), using the ProSimPlus simulator. The stages of analysis and simulation followed the methodology of Douglas (1985), based on heuristic rules for decision making of process design. To simulate the process, a thermodynamic study was carried out and two models were chosen based on the pressure zone of the process: the NRTL-Gas Ideal model for low-pressure zone; and the SRK-MHV2-UNIQUAC model for the high-pressure zone. The intensification of the process separation zone was aimed to transform the distillation columns D2 and D3 into a single column. However, it was not successful, as the product recovery specifications were not respected. Thus, the separation scheme with columns D2 and D3 was maintained. Finally, the heat integration of the process was done using Simulis Pinch, with two heat exchanger networks. The second network had an energy recovery of 98.7%, corresponding to a reduction of 175.5 GWh / year in the consumption of the HDA process. It is concluded then that through the methodology of Douglas (1985), the simulation of an industrial process can become more organized, thus reducing its development time.