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ForewordThe purpose of this techno-economic analysis is to compare a set of biofuel conversion technologies selected for their promise and near-term technical viability. Every effort has been made to make this comparison on an equivalent basis using common assumptions. The process design and parameter value choices underlying this analysis are based on public domain literature only. For these reasons, the results are not indicative of potential performance. Rather they are meant to represent the most likely performance given the current state of public knowledge.iv List of Acronyms Executive SummaryA techno-economic analysis on the production of cellulosic ethanol by fermentation was conducted to understand the viability of liquid biofuel production processes within the next 5-8 years. Initially, 35 technologies were reviewed and a matrix was prepared considering economics, technological soundness and maturity, environmental aspects, process performance, and technical and economic risks. Then, a two-step down selection was performed to choose scenarios to be evaluated in a more detailed economic analysis. In the first screening, the lignocellulosic ethanol process was selected because it is well studied and portions of the process have been tested at pilot scales. In the second screening, seven scenarios of process variations were selected: four variations involved pretreatment (dilute acid, two-stage dilute acid, hot water, and ammonia fiber explosion) and three variations involved downstream processes (pervaporation, separate 5-carbon and 6-carbon sugar fermentation, and on-site enzyme production). Each of these scenarios was examined in detail. Given the time needed for design, construction, and startup of large process plants, plants operating in the 5-8 year timeframe would likely need to be based on recent experimental data. For this work, process designs were constrained to public data published in 2007 or earlier, without projecting for future process improvements. Economic analysis was performed for an "n th plant" (mature technology) to obtain total investment and product value (PV) (defined as value of the product needed for a net present value of zero with a 10% internal rate of return). The final selection among the scenarios was performed primarily based on the PV. Sensitivity analysis was performed on PV to assess the impact of variations in process and economic parameters. Results show that the modeled dilute acid pretreatment process without any downstream process variation had the lowest PV of $3.40/gal of ethanol (which is $5.15/gallon of gasoline equivalent, GGE) in 2007 dollars. Sensitivity analysis shows that PV is most sensitive to feedstock and enzyme costs.The cellulosic ethanol process is a new technology, for which a pioneer plant is expected to be significantly more expensive than the n th plant. To assess the impact of technology maturity on pioneer plant cost, a cost growth analysis was performed following a method documented in a RAND Corporation report. This methodology attempts ...

Study on Napier grass leaf (NGL), stem (NGS) and leaf and stem (NGT) was carried out. Proximate, ultimate and structural analyses were evaluated. Functional groups and crystalline components in the biomass were examined. Pyrolysis study was conducted in a thermogravimetric analyzer under nitrogen atmosphere of 20 mL/min at constant heating rate of 10 K/min. The results reveal that Napier grass biomass has high volatile matter, higher heating value, high carbon content and lower ash, nitrogen and sulfur contents. Structural analysis shows that the biomass has considerable cellulose and lignin contents which are good candidates for good quality bio-oil production. From the pyrolysis study, degradation of extractives, hemicellulose, cellulose and lignin occurred at temperature around 478, 543, 600 and above 600 K, respectively. Kinetics of the process was evaluated using reaction order model. New equations that described the process were developed using the kinetic parameters and data compared with experimental data. The results of the models fit well to OPEN ACCESSEnergies 2015, 8 3404 the experimental data. The proposed models may be a reliable means for describing thermal decomposition of lignocellulosic biomass under nitrogen atmosphere at constant heating rate.