Sensitivity assessment of value-added products and pellet production in alternatives for softwood sawdust valorization

The study involves alternatives for pine sawdust valorization. It includes pellet production as the base case and two biorefinery schemes to produce levulinic acid (LA) and its by-products (furfural and formic acid). The studied scenarios consider an annual capacity of 100,000 of dry sawdust. In scenario I, 108 kt per year of pellets could be obtained with an investment of USD 9.5 million and USD 19.7 million of net present value (NPV). In scenario II, the production of 17.6 kt year(-1) of pellets and 5.72 kt year of LA and its by-products requires an investment of USD 52.7 million (NPV about USD 5.6 million). In scenario III, 16.3 kt year(-1) of LA and derived products could be obtained with USD 54.5 million investment (NPV about USD 60 million). Pellet price and sawdust availability are the most critical variables in scenario I. Scenarios II and III show that the most significant variables are the conversion yield and sugar concentration in the acid catalysis, LA price, and sawdust availability. Besides, a sensitivity analysis was developed, varying more than one variable at a time in all scenarios. In scenario III, NPV values can be higher than USD 180 million.