Limits for sustainable biosurfactant production: Techno-economic and environmental assessment of a rhamnolipid production process

A techno-economic and environmental assessment of a di-rhamnolipid production process is presented. The process was designed based on patents describing industrial-scale glycolipid production. Glucose, glycerol, soybean oil, and stearic acid were tested as feedstocks. Maximum theoretical substrate-to-product yields were used. The simulation process was simulated using Aspen Plus v9.0. The techno-economic assessment was performed to elucidate the best feedstock. In addition, an environmental analysis was conducted using SimaPro v8.3. The highest productivity was calculated for stearic acid (3.57 kg di-rhamnolipid/t/d). The specific energy consumption and capital investment ranged from 1.8 MJ/kg to 6.1 MJ/kg and 1.8 to 2.8 M.USD, respectively. Stearic acid was identified as the most suitable raw material since the production cost was 12 USD/kg and the carbon footprint was 7.58 kg_CO2-eq/kg. The environmental results elucidated that energy consumption as the most important hotspot. As conclusion, stearic acid is a promising option for producing di-rhamnolipids.