Techno-Economic and Life Cycle Assessment of Wastewater Management from Potato Starch Production: Present Status and Alternative Biotreatments

Abstract

Potato liquor, a byproduct of potato starch production, is steam-treated to produce protein isolate. The heat treated potato liquor (HTPL), containing significant amounts of organic compounds, still needs to be further treated before it is discarded. Presently, the most common strategy for HTPL management is concentrating it via evaporation before using it as a fertilizer. In this study, this scenario was compared with two biotreatments: (1) fermentation using filamentous fungus R. oryzae to produce a protein-rich biomass, and (2) anaerobic digestion of the HTPL to produce biogas. Technical, economic and environmental analyses were performed via computational simulation to determine potential benefits of the proposed scenarios to a plant discarding 19.64 ton/h of HTPL. Fungal cultivation was found to be the preferred scenario with respect to the economic aspects. This scenario needed only 46% of the investment needed for the evaporation scenario. In terms of the environmental impacts, fungal cultivation yielded the lowest impacts in the acidification, terrestrial eutrophication, freshwater eutrophication, marine eutrophication and freshwater ecotoxicity impact categories. The lowest impact in the climate change category was obtained when using the HTPL for anaerobic digestion.

Microbial Resources, Fermentation and Reduction of Negative Externalities in Food Systems: Patterns toward Sustainability and Resilience

“…Some studies proposed pathways towards enhanced nutrient bioavailability [10,[58][59][60] and improved human health/well-being [61][62][63][64] (including microbiome therapies [63][64][65][66]), advances of interest to contrast the adverse effects of some negative externalities. Furthermore, the design of several works looking at reducing resource dissipation, saving energy [52,69], valorising foods by-products [52,70,71], foods wastes [72][73][74], and wastewater [75][76][77]. Finally, some strategies can preserve microbial diversity associated with food fermentation [78][79][80].…”

Use of Organic Wastes and Industrial By-Products to Produce Filamentous Fungi with Potential as Aqua-Feed Ingredients

“…They reported that although the integrated process imposed greater capital costs than only fungal cultivation on stillage, it could result in up to 48% increase in the net present value (NPV). In another work, Souza Filho et al [41] performed a technical and economical evaluation, and a life cycle assessment (LCA) on the production of filamentous fungal biomass from potato liquor, a by-product of potato starch production. This research focused on different treatment scenarios for heat-treated potato liquor, with one including the application of final fungal biomass as a fish feed supplement.…”

Towards maximum value creation from potato protein liquor: volatile fatty acids production from fungal cultivation effluent

“…In current practices, residual effluents from the potato starch industry usually end up as fertilizer [5]. This common Highlights • Fungal cultivation effluent is a potential feedstock for VFA production.…”

“…scenario has been compared with other scenarios in different literatures [5] and the use of PPL for the cultivation of fungal biomass and proteins [6,7], yeast biomass [8], and enzyme production [9] was investigated. PPL has been valorized through conversion of a high fraction of its nutrients into food and feed grade fungal biomass in a previous study [7].…”