Diversifying the technological strategies for recovering bioenergy from the two-phase anaerobic digestion of sugarcane vinasse: An integrated techno-economic and environmental approach. (July 2018)

• Record Type: Journal Article
• Authors: Fuess, Lucas Tadeu; Klein, Bruno Colling; Chagas, Mateus Ferreira; Alves Ferreira Rezende, Mylene Cristina; Garcia, Marcelo Loureiro; Bonomi, Antonio; Zaiat, Marcelo
• Is Part Of: Renewable energy. Volume 122(2018)
• Page Start: 674
• Page End: 687
• Publication Date: 2018-07
• Subjects: Two-phase biodigestion -- Sugarcane vinasse -- Techno-economic assessment -- Life cycle assessment -- Bioenergy recovery; AD anaerobic digestion -- ALO agricultural land occupation -- BFR biogas flow rate -- CB-0 reference scenario -- CC combined cycle -- CE-1–CE-5 energy scenarios -- CH carbohydrate concentration -- COD chemical oxygen demand -- CODacid COD of acidified vinasse -- CODraw COD of raw vinasse -- EC carbohydrates -- ECCH carbohydrate conversion -- EEP electric energy production -- ER-COD, ERCOD COD removal -- EtOH ethanol -- FDP fossil depletion potential -- fCH4 methane proportion in biogas -- fH2 hydrogen proportion in biogas -- FWE fresh water eutrophication -- GHG greenhouse gas -- GTB gas turbine -- GWP global warming potential -- HTP human toxicity potential -- HY hydrogen yield -- ICE internal combustion engine -- IRR internal rate of return -- LCA life cycle assessment -- LHV lower heating value -- M molar mass of sucrose -- MARR minimum acceptable rate of return -- MY methane yield -- NPV net present value -- OLR organic loading rate -- OPEX operational expenditure -- R ideal gas constant -- STB steam turbine -- T operating temperature -- TAP terrestrial acidification potential -- TC ton of sugarcane -- TEP thermal energy production -- VFA volatile fatty acid -- VFR vinasse flow rate -- VSB Virtual Sugarcane Biorefinery; Renewable energy sources -- Periodicals; Power resources -- Periodicals; Énergies renouvelables -- Périodiques; Ressources énergétiques -- Périodiques; 333.794
• DOI: 10.1016/j.renene.2018.02.003
• Languages: English
• ISSNs: 0960-1481

Abstract

Abstract: Technical, economic and environmental aspects of implementing two-phase anaerobic digestion (AD), i.e., acidogenic + methanogenic systems, in sugarcane biorefineries for the treatment of vinasse were assessed based on different strategies to using the hydrogen-rich biogas (biogas-H2 ) generated via acidogenesis. Phase separation greatly enhanced the bioenergy recovered from vinasse AD compared with single-phase systems (methanogenic phase exclusively). The best results for generating electric energy were observed in combined cycle-based power plants that utilized biohythane (10.8 MW + 5.5 MW for the harvest and inter-harvest, respectively), which is the gaseous biofuel from blending biogas-H2 with the methane-rich stream from the methanogenic phase (biogas-CH4 ). Moreover, the results of this study indicated that scaling up two-phase AD systems is economically feasible for the treatment of sugarcane vinasse (net present value = USD 208.58–219.86 million) because a better or equivalent economic performance was attained compared with single-phase processes. Optimizing the alkalinization of methanogenic reactors strongly affected both the economic and environmental performance of the process, with better results observed with the use of low sodium hydroxide dosages (4 g NaOH kg −1 COD). In summary, our results highlighted that two-phase biodigestion may enhance energy production from vinasse by 20–30% without impairing the profitability of the biorefinery and could lead to slight improvements in the environmental performance of the ethanol production chain via the use of an optimized alkalinization strategy. Graphical abstract: Image Highlights: Full-scale two-phase biodigestion plants applied to sugarcane vinasse were assessed. Techno-economic and environmental aspects were investigated in detail. Different approaches to using the H2 -rich biogas from acidogenesis were considered. Electricity generation was maximized for biohythane in a combined cycle power plant. The scaleup of two-phase biodigestion in biorefineries is economically feasible.