Abstract
Abstract
The techno-economic performance of bacterial nanocellulose (BNC) production by Komagataeibacter sp has been evaluated in a process utilising second generation sugars, more specifically glucose derived from forestry residues via their delignification pretreatment and subsequent enzymatic hydrolysis towards sugars. Two distinct scenarios were evaluated. In the first scenario, the end product was BNC with 15 wt. % moisture, it involved a drying step. In the second scenario, the end product was a BNC hydrogel containing 99 wt. % water. To achieve a payback period (PBP) of 8 years minimum selling prices of 202.9 €/kg and 2.07 €/kg were calculated for scenarios A and B respectively. A sensitivity analysis showed that the main contributor to the process cost was the fixed capital investment (FCI) and more specifically the cost of the seed growth reactors and the tray bioreactors that accounted for around 77% of the FCI. In terms of annual costs, peptone as a raw material, electricity costs and wastewater treatment costs were the main contributors. Designing a more efficient process with lower cost bioreactors, higher automation and shorter fermentation cycles can help cut down the total product cost. In addition, understanding how dewatering and drying of the BNC affect its properties and designing an efficient drying section is key to minimizing process costs. Strategies for wastewater treatment also need to be considered as there are high volumes of wastewater that necessitate its efficient and sustainable treatment so that ideally fresh water consumption is minimized.