Vargas Gabriel Gomes, Flórez-Orrego Daniel Alexander, de Oliveira Junior Silvio
Polytechnic School, University of São Paulo, Av. Luciano Gualberto 380, São Paulo 05508-010, Brazil.
Industrial Process and Energy Systems Engineering, École Polytechnique Fédérale de Lausanne EPFL, Sion, 1950 Valais, Switzerland.
Entropy (Basel). 2023 Jul 22;25(7):1098. doi: 10.3390/e25071098.
The need to reduce the dependency of chemicals on fossil fuels has recently motivated the adoption of renewable energies in those sectors. In addition, due to a growing population, the treatment and disposition of residual biomass from agricultural processes, such as sugar cane and orange bagasse, or even from human waste, such as sewage sludge, will be a challenge for the next generation. These residual biomasses can be an attractive alternative for the production of environmentally friendly fuels and make the economy more circular and efficient. However, these raw materials have been hitherto widely used as fuel for boilers or disposed of in sanitary landfills, losing their capacity to generate other by-products in addition to contributing to the emissions of gases that promote global warming. For this reason, this work analyzes and optimizes the biomass-based routes of biochemical production (namely, hydrogen and ammonia) using the gasification of residual biomasses. Moreover, the capture of biogenic CO aims to reduce the environmental burden, leading to negative emissions in the overall energy system. In this context, the chemical plants were designed, modeled, and simulated using Aspen plus™ software. The energy integration and optimization were performed using the OSMOSE Lua Platform. The exergy destruction, exergy efficiency, and general balance of the CO emissions were evaluated. As a result, the irreversibility generated by the gasification unit has a relevant influence on the exergy efficiency of the entire plant. On the other hand, an overall negative emission balance of -5.95 kg/kg in the hydrogen production route and -1.615 kg/kg in the ammonia production route can be achieved, thus removing from the atmosphere 0.901 t/t and 1.096 t/t, respectively.
减少化工行业对化石燃料的依赖这一需求，近来促使这些行业采用可再生能源。此外，由于人口不断增长，处理和处置农业生产过程中的残余生物质（如甘蔗渣和橙皮渣），甚至是人类废弃物（如污水污泥），将成为下一代面临的一项挑战。这些残余生物质可以成为生产环境友好型燃料的有吸引力的替代选择，并使经济更加循环和高效。然而，这些原材料迄今广泛用作锅炉燃料或被处置在卫生填埋场，除了导致促进全球变暖的气体排放外，还失去了产生其他副产品的能力。因此，本研究利用残余生物质的气化过程，分析并优化了基于生物质的生化生产路线（即氢气和氨气）。此外，捕获生物源二氧化碳旨在减轻环境负担，从而在整个能源系统中实现负排放。在此背景下，使用Aspen plus™软件对化工厂进行了设计、建模和模拟。利用OSMOSE Lua平台进行了能量集成和优化。评估了火用损失、火用效率和二氧化碳排放的总体平衡。结果表明，气化单元产生的不可逆性对整个工厂的火用效率有显著影响。另一方面，氢气生产路线的总体负排放平衡可达-5.95 kg/kg，氨气生产路线可达-1.615 kg/kg，从而分别从大气中去除0.901 t/t和1.096 t/t。
