Improvement of the monochlorobenzene separation process through heat integration: A sustainability-based assessment

Chlorobenzene is an important chemical intermediate in the production of commodities, such as herbicides, dyestuffs, and rubber. In this work, a heat integration was proposed for a monochlorobenzene separation process. The conventional process structure and the proposed integrated one were designed and simulated. An optimization focused on minimizing the cooling and heating costs was performed to obtain the best-operating conditions for the heat integration. The simulation of a utility plant, including cooling water and steam generation sections, was also carried out for more accurate estimations of CO2 emissions, water, energy consumption, and operating costs. The processes were evaluated and compared in terms of their sustainable performances using the eco-efficiency comparison index method and environmental and economic indicators, such as CO2 emission, water consumption, and utility cost, to assess the benefits of heat integration. The results demonstrated that the proposed strategy reduced around 57% of all environmental impacts and utility costs. As the composite evaluation index from the performance indicators showed, the proposed optimal heat integrated industrial plant significantly improved the initial processes’ eco-efficiencies, up to 83%, proving a suitable strategy for a more sustainable process.