Alternative Integrated Ethanol, Urea, and Acetic Acid Processing Routes Employing CCU: A Prospective Study through a Life Cycle Perspective

Abstract

Despite the importance of inputs such as urea, ethanol, and acetic acid for the global production of food, energy, and chemical bases, manufacturing these substances depends on non-renewable resources, generating significant environmental impacts. One alternative to reducing these effects is to integrate production processes. This study compares the cumulative environmental performance of individual production routes for ethanol, urea, and acetic acid with that of an integrated complex designed based on Industrial Ecology precepts. Life Cycle Assessment was used as a metric for the impact categories of Global Warming Potential (GWP) and Primary Energy Demand (PED). The comparison occurred between the reference scenario, which considers individual processes, and six alternative integrated arrangements that vary in the treatment given to a stream concentrated in fuels generated in the Carbon Capture and Usage system that serves the processing of acetic acid. The study showed that process integration is recommended in terms of PED, whose contributions were reduced by 46–63% compared to stand-alone processes. The impacts of GWP are associated with treating the fuel stream. If it is treated as a co-product and environmental loads are allocated in terms of energy content, gains of up to 44% can be expected. On the other hand, if the stream is a waste, the complex’s GWP becomes more aggressive than the baseline scenario by 66%.