Techno-economic analysis of low moisture anhydrous ammonia (LMAA) pretreatment for butanol production from oil palm frond

Cellulosic butanol production has been of interest because of the attractive properties of butanol as a fuel and its ability in environmental preservation. Biological pathway for butanol production is currently a subject of development efforts from various processing aspects. One crucial stage is the pretreatment process, which has considerably affected the production cost of butanol. There are some concerns regarding the overall effectiveness of the process, including high total energy and liquid requirement, and production of inhibitory compounds from the pretreatment process. Low-moisture anhydrous ammonia (LMAA) pretreatment, which requires less water, work at atmospheric conditions, and gives milder pretreatment intensity, was developed to solve these problems. In this study, the techno-economic analysis (TEA) of butanol production from oil palm fronds (OPF) was conducted. The simulation employed LMAA pretreatment, followed by ABE fermentation and downstream processing. The lowest butanol production cost was $ 2.11/L, which was recorded from 95.34 x 10(6) L butanol/y plant capacity. Detail analysis of each cost component revealed that operating costs contributing nearly 63% of the production cost with 24% and 17% contribution from utility and material costs, respectively. Optimization of process parameters estimated the potential of production cost reduction to lower than $ 1.65/L by an increase in the enzyme hydrolysis yield. The study aimed to provide data towards utilization effort of OPF, especially for butanol production.