Use of corn fractionation techniques in dry grind process increases the number of coproducts, enhances their quality and value, generates feedstock for cellulosic ethanol production and potentially increases profitability of the dry grind process. The aim of this study is to develop process simulation models for eight different wet and dry corn fractionation techniques recovering germ, pericarp fiber and/or endosperm fiber, and evaluate their techno-economic feasibility at the commercial scale. Ethanol yields for plants processing 1113.11 MT corn/day were 37.2 to 40 million gal for wet fractionation and 37.3 to 31.3 million gal for dry fractionation, compared to 40.2 million gal for conventional dry grind process. Capital costs were higher for wet fractionation processes ($92.85 to $97.38 million) in comparison to conventional ($83.95 million) and dry fractionation ($83.35 to $84.91 million) processes. Due to high value of coproducts, ethanol production costs in most fractionation processes ($1.29 to $1.35/gal) were lower than conventional ($1.36/gal) process. Internal rate of return for most of the wet (6.88 to 8.58%) and dry fractionation (6.45 to 7.04%) processes was higher than the conventional (6.39%) process. Wet fractionation process designed for germ and pericarp fiber recovery was most profitable among the processes.
The production of biodiesel from conventional oilseed crops (e.g., soybean) is limited by the low productivity of oil per hectare. Oilcane (derived from sugarcane) holds the potential to improve vegetable oil production in agriculture to help meet projected demand for oil-based biofuels. However, the financial viability of oilcane-derived biofuels remains uncertain, with key questions centered on the technical feasibility of vegetative oil recovery and the economic/environmental implications of designing integrated biorefineries to process multiple oil-rich feedstocks. To address these questions, two biorefinery configurations producing biodiesel and ethanol were evaluated: (i) direct cogeneration of heat and power from bagasse (lower oil recovery) and (ii) an integrated, single-step co-fermentation of both extruded juice and bagasse hydrolysate (higher oil recovery). Sensitivity and uncertainty analyses demonstrated the sustainability gains of improved oil recovery, higher feedstock oil content, and the integration of oil-sorghum processing when oilcane is not in season. For the direct cogeneration and co-fermentation configurations, Monte Carlo simulations resulted in maximum feedstock purchase prices of 34.7 [22.4, 48.4] (median; 5th and 95th percentiles in brackets) and 40.0 [19.3, 63.7] USD•MT −1 and life cycle global warming potentials of 0.313 [0.285, 0.345] and 0.320 [0.294, 0.351] kg CO 2 -eq•L −1 of ethanol (under economic allocation), respectively.
Anthropogenic
discharge of excess phosphorus (P) to water bodies
and increasingly stringent discharge limits have fostered interest
in quantifying opportunities for P recovery and reuse. To date, geospatial
estimates of P recovery potential in the United States (US) have used
human and livestock population data, which do not capture the engineering
constraints of P removal from centralized water resource recovery
facilities (WRRFs) and corn ethanol biorefineries where P is concentrated
in coproduct animal feeds. Here, renewable P (rP) estimates from plant-wide
process models were used to create a geospatial inventory of recovery
potential for centralized WRRFs and biorefineries, revealing that
individual corn ethanol biorefineries can generate on average 3 orders
of magnitude more rP than WRRFs per site, and all corn ethanol biorefineries
can generate nearly double the total rP of WRRFs across the US. The
Midwestern states that make up the Corn Belt have the largest potential
for P recovery and reuse from both corn biorefineries and WRRFs with
a high degree of co-location with agricultural P consumption, indicating
the untapped potential for a circular P economy in this globally significant
grain-producing region.
Conversion of corn fiber to ethanol in the dry grind process can increase ethanol yields, improve coproduct quality and contribute to process sustainability. This work investigates the use of two physio-chemical pretreatments on corn fiber and effect of cellulase enzyme dosage to improve ethanol yields. Fiber separated after liquefaction of corn was pretreated using (I) hot water pretreatment (160 °C for 5, 10 or 20 min) and (II) wet disk milling and converted to ethanol. The conversion efficiencies of hot water pretreated fiber were higher than untreated fiber, with highest increase in conversion (10.4%) achieved for 5 min residence time at 160 °C. Disk milling was not effective in increasing conversion compared to other treatments. Hydrolysis and fermentation of untreated fiber with excess cellulase enzymes resulted in 33.3% higher conversion compared to untreated fiber.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.