Techno‐economic assessment of bio‐refinery model based on co‐pyrolysis of cotton boll crop‐residue and plastic waste

This study evaluated the techno‐economic aspects of empty cotton boll valorization to liquid fuel (moisture free bio‐oil), potash fertilizer, and activated carbon. Three different plant capacities, in terms of feedstock handling capacities were considered: 50, 100, and 200 t day−1. For each plant capacity, three plant variants were considered: only fuel, fuel + potash fertilizer, and fuel + potash fertilizer + activated carbon. The net present value ranged from 7.73 M$ for a 50 t day−1 plant to 47.38 M$ for a 200 t day−1 plant, producing liquid fuel along with fertilizer and activated carbon. The overall profitability of the plant was improved by higher plant capacity. For a 200 t day−1 plant, equipment purchase cost related to the synthesis of fuel, potash fertilizer and activated carbon contributed 32.87, 25.77, and 41.36%, respectively to the total purchase equipment cost of the entire plant. Among the three products, activated carbon contributed 81.03% to the total revenue generated by the entire plant. The sensitivity of plant economics towards feedstock price, selling price of activated carbon, potassium hydroxide recovery, annual interest rates, and total capital investment was examined. The economic competitiveness for this kind of thermo‐chemical conversion was assessed in comparison with the solar gasification route. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd