Renewable fuel standards for biofuels have been written into policy in the U.S. to reduce the greenhouse gas (GHG) intensity of transportation energy supply. Biofuel feedstocks sourced from within a regional market have the potential to also address sustainability goals. The U.S. Mid-Atlantic region could meet the advanced fuel designation specified in the Renewable Fuel Standard (RFS2), which requires a 50% reduction in GHG emissions relative to a gasoline baseline fuel, through ethanol produced from winter barley (Hordeum vulgare L.). We estimate technology configurations and winter barley grown on available winter fallow agricultural land in six Mid-Atlantic states. Using spatially weighted stochastic GHG emission estimates for winter barley supply from 374 counties and biorefinery data from a commercial dry-grind facility design with multiple co-products, we conclude that winter barley would meet RFS2 goals even with the U.S. EPA’s indirect land use change estimates. Using a conservative threshold for soil GHG emissions sourced from barley produced on winter fallow lands in the U.S. MidAtlantic, a biorefinery located near densely populated metropolitan areas in the Eastern U.S. seaboard could economically meet the requirements of an advanced biofuel with the co-production of CO2 for the soft drink industry.

Computer simulation is a useful tool for benchmarking electrical and fuel energy consumption and water use in a fluid milk plant. In this study, a computer simulation model of the fluid milk process based on high temperature, short time (HTST) pasteurization was extended to include models for processes for shelf-stable milk and extended shelf-life milk that may help prevent the loss or waste of milk that leads to increases in the greenhouse gas (GHG) emissions for fluid milk. The models were for UHT processing, crossflow microfiltration (MF) without HTST pasteurization, crossflow MF followed by HTST pasteurization (MF/HTST), crossflow MF/HTST with partial homogenization, and pulsed electric field (PEF) processing, and were incorporated into the existing model for the fluid milk process. Simulation trials were conducted assuming a production rate for the plants of 113.6 million liters of milk per year to produce only whole milk (3.25%) and 40% cream. Results showed that GHG emissions in the form of process-related CO2 emissions, defined as CO2 equivalents (e)/kg of raw milk processed (RMP), and specific energy consumptions (SEC) for electricity and natural gas use for the HTST process alone were 37.6 g of CO(2)e/kg of RMP, 0.14 MJ/kg of RMP, and 0.13 MJ/kg of RMP, respectively. Emissions of CO2 and SEC for electricity and natural gas use were highest for the PEF process, with values of 99.1 g of CO(2)e/kg of RMP, 0.44 MJ/kg of RMP, and 0.10 MJ/kg of RMP, respectively, and lowest for the UHT process at 31.4 g of CO(2)e/kg of RMP, 0.10 MJ/kg of RMP, and 0.17 MJ/kg of RMP. Estimated unit production costs associated with the various processes were lowest for the HTST process and MF/HTST with partial homogenization at $0.507/L and highest for the UHT process at $0.60/L. The increase in shelf life associated with the UHT and MF processes may eliminate some of the supply chain product and consumer losses and waste of milk and compensate for the small increases in GHG emissions or total SEC noted for these processes compared with HTST pasteurization alone. The water use calculated for the HTST and PEF processes were both 0.245 kg of water/kg of RMP. The highest water use was associated with the MF/HTST process, which required 0.333 kg of water/kg of RMP, with the additional water required for membrane cleaning. The simulation model is a benchmarking framework for current plant operations and a tool for evaluating the costs of process upgrades and new technologies that improve energy efficiency and water savings.

The cost of high pressure processing (HPP) and the environmental impact of pulsed electric fields (PEF), HPP and thermal pasteurization of orange juice were estimated in the US. The cost analysis was based on commercial processing conditions that were validated for a 2-month shelf-life of orange juice under refrigeration conditions. Total electricity consumption was estimated to be 38,100 and 1,000,000 k Wh/year for thermal and HPP processing, respectively. Total pasteurization cost of HPP was estimated to be 10.7 ¢/l for processing 16,500,000 l/year (3,000 l/h). Of this, capital costs accounted for 59 % (6.3 ¢/l), labor costs accounted for 37 % (4.0 ¢/l) and utility charges, mainly electricity, accounted for 4 % (0.4 ¢/l). The total HPP cost was 7-folds higher than that of conventional thermal processing (1.5 ¢/l). The equivalent CO2 emission was 90,000 kg for thermal processing and 700,000 and 773,000 kg for PEF and HPP, respectively. This corresponds to an increase between 7- and 8-folds in comparison to the thermal processing. Increasing the production output by 2- to 6-folds reduced the total production costs of nonthermal processing by 50–75 %. A deeper knowledge of the processing costs and environmental impact of nonthermal technologies will afford companies a better understanding of the benefits and limitations of these novel systems.

Methyl-branched fatty acids produced by isomerization of oleic acid ('isostearic' acids (IA)) are industrially useful products with excellent thermostabilities and lubricities and reduced freezing points relative to stearic acid. They have potential utility as biodiesel or a biodiesel additive imparting improved low temperature fluidity. We present a techno-economic model for industrial scale production of isostearic acid by zeolite-catalyzed isomerization. A catalyst regeneration loop allowing 20 reaction cycles was included. Use of catalyst for 15 or more reaction cycles reduced process cost by 51% vs. a single use reaction format. However, with a best-case predicted production cost of $2.375/kg ($1.080/lb), further process cost reductions will be required before use of IA esters as high percentage blend components of biodiesel is economically feasible.

The effects of acid protease and urea addition during the fermentation step were evaluated. The fermentations were also tested with and without the addition of urea to determine if protease altered the nitrogen requirements of the yeast. Results show that the addition of the protease had a statistically significant effect on the fermentation rate and yield. Fermentation rates and yields were improved with the addition of the protease over the corresponding controls without protease. Protease addition either with or with added urea resulted in a higher final ethanol yield than without the protease addition. Urea addition levels >1200 ppm of supplemental nitrogen inhibited ethanol production. The economic effects of the protease addition were evaluated by using process engineering and economic models developed at the Eastern Regional Research Center. The decrease in overall processing costs from protease addition was as high as $0.01/L (4 ¢/gal) of denatured ethanol produced.

Bovine hide presoaking solutions formulated with crude glycerol and only a quarter of the amount of biocide (such as Proxel-GXL) and surfactant (such as Boron-TS or Busan1009) that the industry is commonly using, have recently been developed and are effective in removing adobe type manure attached to the cattle hide. The goal of this research project was to investigate potential effects of incorporating enzymes that can attack the adobe type manure and could break down adhesion to hide and enhance its removal. If an optimal amount of cellulase or xylanase used individually or in a combination of both was included, lowering the concentration of crude glycerol from 10% to 5% is feasible. From conclusive results, the combination of cellulase and xylanase worked synergistically because a lower concentration of each than when used individually also has demonstrated improvement in manure softening efficiency. The texture analysis of soaked hardened manure showed that the enzymes were quite promising in softening which can be translated to loosening and eventually the enhancement of hardened manure removal. Chlorine dioxide also was incorporated in the formulation and was associated with a reduction in manure odor. The inclusion of sodium hydroxide in the formulation had also enhanced the microbial growth inhibition of pathogenic bacteria that were tested. The cost of implementing the new formulations is similar to those traditionally used by the industry. In addition, the new soaking solutions have a more favorable impact on the environment.

Energy-savings measures have been implemented in fluid milk plants to lower energy costs and the energy-related carbon dioxide (CO2) emissions. Although these measures have resulted in reductions in steam, electricity, compressed air, and refrigeration use of up to 30%, a benchmarking framework is necessary to examine the implementation of process-specific measures that would lower energy use, costs, and CO2 emissions even further. In this study, using information provided by the dairy industry and equipment vendors, a customizable model of the fluid milk process was developed for use in process design software to benchmark the electrical and fuel energy consumption and CO2 emissions of current processes. It may also be used to test the feasibility of new processing concepts to lower energy and CO2 emissions with calculation of new capital and operating costs. The accuracy of the model in predicting total energy usage of the entire fluid milk process and the pasteurization step was validated using available literature and industry energy data. Computer simulation of small (40.0 million L/yr), medium (113.6 million L/yr), and large (227.1 million L/yr) processing plants predicted the carbon footprint of milk, defined as grams of CO2 equivalents (CO2e) per kilogram of packaged milk, to within 5% of the value of 96 g of CO 2e/kg of packaged milk obtained in an industry-conducted life cycle assessment and also showed, in agreement with the same study, that plant size had no effect on the carbon footprint of milk but that larger plants were more cost effective in producing milk. Analysis of the pasteurization step showed that increasing the percentage regeneration of the pasteurizer from 90 to 96% would lower its thermal energy use by almost 60% and that implementation of partial homogenization would lower electrical energy use and CO2e emissions of homogenization by 82 and 5.4%, respectively. It was also demonstrated that implementation of steps to lower non-process-related electrical energy in the plant would be more effective in lowering energy use and CO2e emissions than fuel-related energy reductions. The model also predicts process-related water usage, but this portion of the model was not validated due to a lack of data. The simulator model can serve as a benchmarking framework for current plant operations and a tool to test cost-effective process upgrades or evaluate new technologies that improve the energy efficiency and lower the carbon footprint of milk processing plants.

The cost of pulsed electric field (PEF) pasteurization of orange juice was estimated. The cost analysis was based on processing conditions that met the US FDA (5 log reduction) requirement for fruit juice pasteurization and that achieved a sufficient microbial shelf-life. PEF-treated samples processed at 30 kV/cm and 60 degrees C had reductions in Escherichia coli, Salmonella Typhimurium and Lactobacillus spp. of greater than 5 log and had a microbial shelf-life of 2 months at 4 degrees C. Total pasteurization cost was estimated to be 3.7 cent/L. Of this, capital costs accounted for 54% (2.0 cent/L), labor costs accounted for 35% (1.3 cent/L) and utility charges, mainly electricity, accounted for 11% (0.4 cent/L). The total PEF cost was 147% (2.2 cent/L) more than that of conventional thermal processing (1.5 cent/L). A deeper knowledge of the processing costs of PEF technology will afford companies a better understanding of the benefits and limitations of nonthermal processing.Industrial relevance: Pasteurization of orange juice by pulsed electric fields (PEF) results in a higher quality product compared to traditional thermal pasteurization. However, industry has not embraced this new technology and the main reason for this may be the lack of a comprehensive cost analysis. A large-scale commercial PEF system was designed and the total pasteurization cost was estimated to be 3.7 cent/L. The total PEF cost was 2.2 cent/L more than that of traditional thermal processing. A thorough knowledge of the processing costs will provide companies with a better understanding of the pros and cons of PEF pasteurization. Published by Elsevier Ltd.

Sophorolipids are microbial glycolipids that possess surfactant-type properties. Sophorolipids have been tested successfully in a number of potential industrial and niche applications but are generally acknowledged to require higher production costs when compared to petroleum-based surfactants. The objective of this study was to develop a process economic model for the fermentative synthesis of sophorolipids using contemporary process simulation software and current reagent, equipment, and supply costs, following current production practices. Glucose (Glc) and either high oleic sunflower oil (HOSO) or oleic acid (OA) were used as feedstocks and the annual production capacity of the plant was set at 90.7 million kg/year with continuous operation of 24 h a day for 330 days per year. Major equipment costs were calculated to be US$17.1 million but other considerations such as capital, labor, material and utilities costs were also included. The single greatest contributor to the overall production/operating cost was raw materials, which accounted for 89 and 87 % of the total estimated production expenditures for the HOSO and OA-based fermentations, respectively. Based on this model and yields of 100 g/L, the cost of large-scale sophorolipid synthesis via fermentation from Glc:HOSO was calculated to be US$2.95/kg ($1.34/lb) and from Glc:OA to be US$2.54/kg ($1.15/lb). The model is flexible and can be adjusted to reflect changes in capital, production and feedstock costs as well as changes in the type of feedstocks used.

Bio-oils produced from small-scale pyrolysis may have economic and environmental benefits for both densifying agricultural biomass and supplying local bioenergy markets with fossil energy alternatives to support state policies (e.g., Renewable Portfolio Standards). We analyze the life cycle greenhouse gas (GHG), energy, and cost tradeoffs for farm-scale bio-oil production via fast pyrolysis of corn stover feedstock and subsequent utilization for power generation in the state of Pennsylvania. We evaluate the life cycle ramifications of either cofiring the biochar coproduct with coal in existing power plants for energy generation, or using the biochar as a land amendment within the agricultural sector. The results show GHG emissions of 217 and 84 g CO(2)e per kWh of bio-oil electricity for coal cofiring and land amendment, respectively. Cofiring biochar with coal displaces more fossil energy than does land application. We discuss the potential for bio-oil and biochar penetrating near-term electricity markets (c. 2015). Our analysis shows that the electricity produced from burning pyrolysis oil and biochar with variable operating costs of $93/MWh and $18/MWh, respectively, are competitive with the fuel oil and coal electricity markets in Pennsylvania within the vicinity of the agricultural sites supplying biomass in spite of the potentially higher NOx emissions due to nitrogen present in the fuel. Small scale pyrolysis bio-oil may be an economically viable and environmentally sustainable near-term option for peak power production and for meeting the state's Renewable Portfolio Standards.

Second generation ethanol bioconversion technologies are under demonstration-scale development for the production of lignocellulosic fuels to meet the US federal Renewable Fuel Standards (RFS2). Bioconversion technology utilizes the fermentable sugars generated from the cellulosic fraction of the feedstock, and most commonly assumes that the lignin fraction may be used as a source of thermal and electrical energy. We examine the life cycle greenhouse gas (GHG) emission and techno-economic cost tradeoffs for alternative uses of the lignin fraction of agricultural residues (corn stover, and wheat and barley straw) produced within a 2000 dry metric ton per day ethanol biorefinery in three locations in the United States. We compare three scenarios in which the lignin is (1) used as a land amendment to replace soil organic carbon (SOC); (2) separated, dried and sold as a coal substitute to produce electricity; and (3) used to produce electricity onsite at the biorefinery. Results from this analysis indicate that for life cycle GHG intensity, amending the lignin to land is lowest among the three ethanol production options (−25 to −2 g CO2e MJ−1), substituting coal with lignin is second lowest (4–32 g CO2e MJ−1), and onsite power generation is highest (36–41 g CO2e MJ−1). Moreover, the onsite power generation case may not meet RFS2 cellulosic fuel requirements given the uncertainty in electricity substitution. Options that use lignin for energy do so at the expense of SOC loss. The lignin–land amendment option has the lowest capital cost among the three options due to lower equipment costs for the biorefinery's thermal energy needs and use of biogas generated onsite. The need to purchase electricity and uncertain market value of the lignin–land amendment could raise its cost compared to onsite power generation and electricity co-production. However, assuming a market value ($50–$100/dry Mg) for nutrient and soil carbon replacement in agricultural soils, and potentially economy of scale residue collection prices at higher collection volumes associated with low SOC loss, the lignin–land amendment option is economically and environmentally preferable, with the lowest GHG abatement costs relative to gasoline among the three lignin co-product options we consider.

Biochar has been heralded as an amendment to revitalize degraded soils, improve soil carbon sequestration, increase agronomic productivity, and enter into future carbon trading markets. However, scientific and economic technicalties may limit the ability of biochar to consistently deliver on these expectations. Past research has demonstrated that biochar is part of the black carbon continuum with variable properties due to the net result of production (e.g., feedstock and pyrolysis conditions) and postproduction factors (storage or activation). Therefore, biochar is not a single entity but rather spans a wide range of black carbon forms. Biochar is black carbon, but not all black carbon is biochar. Agronomic benefits arising from biochar additions to degraded soils have been emphasized, but negligible and negative agronomic effects have also been reported. Fifty percent of the reviewed studies reported yield increases after black carbon or biochar additions, with the remainder of the studies reporting alarming decreases to no significant differences. Hardwood biochar (black carbon) produced by traditional methods (kilns or soil pits) possessed the most consistent yield increases when added to soils. The universality of this conclusion requires further evaluation due to the highly skewed feedstock preferences within existing studies. With global population expanding while the amount of arable land remains limited, restoring soil quality to nonproductive soils could be key to meeting future global food production, food security, and energy supplies; biochar may play a role in this endeavor. Biochar economics are often marginally viable and are tightly tied to the assumed duration of agronomic benefits. Further research is needed to determine the conditions under which biochar can provide economic and agronomic benefits and to elucidate the fundamental mechanisms responsible for these benefits.

This study updates the life cycle greenhouse gas (GHG) emissions for soybean biodiesel with revised system boundaries and the inclusion of indirect land use change using the most current set of agricultural data. The updated results showed that life cycle GHG emission from biodiesel use was reduced by 81.2% compared to 2005 baseline diesel. When the impacts of lime application and soil N2O emissions were excluded for more direct comparison with prior results published by the National Renewable Energy Laboratory (NREL), the reduction was 85.4%. This is a significant improvement over the 78.5% GHG reduction reported in the NREL study. Agricultural lime accounted for 50.6% of GHG from all agricultural inputs. Soil N2O accounted for 18.0% of total agricultural emissions. The improvement in overall GHG reduction was primarily due to lower agricultural energy usage and improved soybean crushing facilities. This study found that soybean meal and oil price data from the past ten years had a significant positive correlation (R-2 = 0.73); hence, it is argued that soybean meal and oil are both responsible for indirect land use change from increased soybean demand It is concluded that when there is a strong price correlation among co-products, system boundary expansion without a proper co-product allocation for indirect land use change produces erroneous results. When the emissions associated with predicted indirect land use change were allocated and incorporated using U.S. EPA model data, the GHG reduction for biodiesel was 76.4% lower than 2005 baseline diesel.

An economical and environmentally friendly whey protein fractionation process was developed using supercritical carbon dioxide (sCO(2)) as an acid to produce enriched fractions of α-lactalbumin (α-LA) and β-lactoglobulin (β-LG) from a commercial whey protein isolate (WPI) containing 20% α-LA and 55% β-LG, through selective precipitation of α-LA. Pilot-scale experiments were performed around the optimal parameter range (T = 60 to 65 °C, P = 8 to 31 MPa, C = 5 to 15% (w/w) WPI) to quantify the recovery rates of the individual proteins and the compositions of both fractions as a function of processing conditions. Mass balances were calculated in a process flow-sheet to design a large-scale, semi-continuous process model using SuperproDesigner® software. Total startup and production costs were estimated as a function of processing parameters, product yield and purity. Temperature, T, pressure, P, and concentration, C, showed conflicting effects on equipment costs and the individual precipitation rates of the two proteins, affecting the quantity, quality, and production cost of the fractions considerably. The highest α-LA purity, 61%, with 80% α-LA recovery in the solid fraction, was obtained at T = 60 °C, C = 5% WPI, P = 8.3 MPa, with a production cost of $8.65 per kilogram of WPI treated. The most profitable conditions resulted in 57%-pure α-LA, with 71% α-LA recovery in the solid fraction and 89% β-LG recovery in the soluble fraction, and production cost of $5.43 per kilogram of WPI treated at T = 62 °C, C = 10% WPI and P = 5.5 MPa. The two fractions are ready-to-use, new food ingredients with a pH of 6.7 and contain no residual acid or chemical contaminants.

For decades, lubricants and hydraulic fluids were almost entirely based on petroleum. In recent years, the potential health risks of these materials as a result of their poor biodegradability have stimulated public awareness and concerns. It is therefore becoming increasingly important to implement environmentally friendly biobased fluids for the chemical industries. The development of new heterogeneous chemocatalytic processes for the conversion of vegetable oils and animal fats into high-value biobased industrial products can also have important positive impacts on the U.S. agriculture industry. Saturated branched-chain fatty acid isomers (sbc-FAs) such as isostearic acid, which are produced from renewable materials, are of interest because of their excellent lubricity and potentially good biodegradability. These unique features make them attractive in many important applications. Currently, sbc-FAs are produced as a byproduct of industrial dimer acid production, are synthesized in small quantities, and are costly to produce. In this paper, an efficient and effective isomerization process that produces predominantly the sbc-FA materials is presented as a case study to evaluate the potential of the technology to be implemented on the industrial scale. The case study was simulated using SuperPro Designer software to estimate the capital and process costs for producing sbc-FAs at an annual production of 4.5 x 10(6) kg (10 X 10(6) lb). The studies show that the process is cost-effective, with an estimated production cost of U.S. $2.53 kg(-1) ($1.15 lb(-1)).

In previous aqueous enzymatic oil extraction (AEOE) experiments we reported a best free oil yield of 49% of the hexane extracted yield of dry fractionated corn germ. In the current experiments, a dispersion of 10% cooked, dry-fractionated germ in water was treated with α-amylase, glucoamylase and a cellulase complex. Free oil was collected by centrifuging a foam fraction of the dispersion. Several dispersion treatments were tried to evaluate their release of free oil and effect on the production of foam. The foam contained up to 8% free oil (dispersed from germ containing 26% oil) and fines oil (not centrifugally separable), protein and germ particles. Treatment with α-amylase and glucoamylase prior to treatment with the commercial cellulase used in previous AEOE studies increased the free oil yields about 25–61% of the hexane-extractable yield. A preliminary cost analysis indicates that oil separation with the amylase enhanced AEOE appears to be preferable to AEOE alone and profitable if crude corn oil cost exceeds $1.1/kg ($0.50/lb).

A process and cost model was developed for fuel ethanol production from winter barley based on the EDGE (Enhanced Dry Grind Enzymatic) process. In this process, in addition to β-glucanases, which are added to reduce the viscosity of the mash, β-glucosidase is also added to completely hydrolyze the oligomers obtained during the hydrolysis of β-glucans to glucose. The model allows determination of capital costs, operating costs, and ethanol production cost for a plant producing 40 million gallons of denatured fuel ethanol annually. A sensitivity study was also performed to examine the effects of β-glucosidase and barley costs on the final ethanol production cost. The results of this study clearly demonstrate the economic benefit of adding β-glucosidase. Lower ethanol production cost was obtained compared to that obtained without β-glucosidase addition in all cases except one where highest β-glucosidase cost allowance and lowest barley cost were used.

The first comprehensive life-cycle assessment (LCA) for soybean biodiesel produced in the U.S. was completed by the National Renewable Energy Laboratory (NREL) in 1998, and the energy inventory for this analysis was updated in 2009 using 2002 data. The continual adoption of new technologies in farming, soybean processing, and for biodiesel conversion affects the life-cycle energy use over time, requiring that LCA practitioners update their models as often as possible. This study uses the most recently available data to update the energy life-cycle of soybean biodiesel and makes comparisons with the two past studies. The updated analysis showed that the fossil energy ratio (FER) of soybean biodiesel was 5.54 using 2006 agricultural data. This is a major improvement over the FER of 3.2 reported in the 1998 NREL study that used 1990 agricultural data and significantly better than the FER of 4.56 reported using 2002 data. The improvements are primarily due to improved soybean yields and more energy-efficient soybean crushing and conversion facilities. The energy input in soybean agriculture was reduced by 52%, in soybean crushing by 58% and in transesterification by 33% per unit volume of biodiesel produced. Overall, the energy input reduction was 42% for the same amount of biodiesel produced. The addition of secondary inputs, such as farm machinery and building materials, did not have a significant effect on the FER. The FER of soybean biodiesel is likely to continue to improve over time because of increases in soybean yields and the development of increasingly energy-efficient technologies.

Polymeric flocculants are widely used in industrial and municipal applications to remove solids from waste water and to inhibit soil erosion. Currently used polymeric flocculants are prepared from non-renewable materials. Recent research has revealed that some proteins can be excellent flocculants. The purpose of this research was to determine if protein-rich, but low value chicken blood can be used as a renewable flocculant. Fractions of chicken blood (CKB) were assayed for flocculation activity, and the magnitude of the activity exhibited by these fractions was compared to that of anionic polyacrylamide (PAM), the most widely used polymeric flocculant. Activity of the CKB fractions was found to be equivalent to that of PAM at slightly acidic pH values. Since, commercial viability requires retention of activity after dehydration, flocculation trials were conducted with reconstituted samples of freeze and spray dried CKB fractions. Some of the reconstituted samples retained satisfactory flocculation activity. Citric, phosphoric and sulfuric acids were tested to determine if their addition stimulated the flocculation activity of a CKB fraction by slightly decreasing the media pH value. All of the acids were effective, but sulfuric acid is the least costly. A preliminary costs estimate of preparing an active spray dried CKB fraction was completed. The cost of an appropriate amount of sulfuric acid is included in the estimate. The estimate shows that spray dried flocculant prepared from CKB is cost competitive to PAM.

A plant trial was conducted at a 54 MGPY dry grind fuel ethanol facility to evaluate the use of enhanced water removal from whole stillage by enzyme addition during fermentation. Laboratory data had previously shown significant improvements in water removal that could potentially result in significant energy and water savings during ethanol production. Plant baseline data was collected for normal operating conditions before and after the enzyme addition and statistically compared to the results collected during the enzyme-treatment period. The results showed a significant increase in the amount of water removed during centrifugation, resulting in a lower-moisture cake. The firing rate of the drier was decreased during the enzyme-addition period, resulting in a 12% reduction in the amount of natural gas required to produce 1 gal of ethanol. DDGS composition was unaffected. Process model simulations developed using the plant trial results showed a decrease in utility consumption for the enzymatic treatment model compared to the conventional model. Sensitivity analysis showed a tradeoff between the enzyme cost and drier’s natural gas savings. Additional sensitivity simulations with enzyme dosing show energy, water, and economic benefits for a wide range of enzyme and natural gas costs. Water use was reduced by up to 14% for processing and 10% overall. Total energy reductions were calculated with the 54 MGPY process model and found to reduce greenhouse gas emissions by approximately 7.2 million kg of CO2 equivalents/yr.