Feasibility of commercial waste biorefineries for cassava starch industries: Techno-economic assessment

Abstract

Cassava waste is a potential bioresource for integrated biorefineries to co-produce bioproducts [succinic acid (SA), glucose syrup (GS), bioethanol] and combined heat and power (CHP). Techno-economic assessments of five biorefinery scenarios for integration in cassava starch plant (200 Mg/d), co-processing 377.83 Mg/h wastewater (CWW), 7.29 Mg/h bagasse (CB) and 450.89 Mg/h stalks (CS), were done using Aspen Plus® to ascertain their potential commercial viability. Scenarios (I) & (II) co-process CB + CWW for biogas and bioethanol production, respectively, and CS for CHP. Scenario (III)-(V) co-process CB + CWW + 10% CS for bioethanol (III), co-producing either GS (IV) or SA (V) and 90% CS for CHP. All scenarios meet CHP demands for biorefinery and starch processing. However, only Scenario (V) products had their minimum selling prices equal to market prices. Thus, integration of SA production (6.9 Mg/h) in a biorefinery co-producing bioethanol and CHP is a potential viable cassava waste biorefinery with economic and environmental benefits.