Sorghum (Sorghum bicolor) has the potential to be used as a cellulosic feedstock for ethanol production due to its diversity and wide adaptation to many different climates. With a wide range of diversity, this crop could be tailored specifically for use as a feedstock for ethanol production. Other factors such as water use efficiency, drought tolerance, yield potential, composition, and established production systems also make sorghum a logical choice as a feedstock for bioenergy production. The objectives of this study were to better understand the biomass potential of different types of sorghum that may be used for energy production, and determine the composition of these sorghums over the season to better understand biomass yield and composition over time. Six commercial sorghum cultivars or hybrids that represent sorghum types from grain to energy were evaluated near College Station, Texas during the 2008 and 2009 cropping years. An optimal harvest window (defined by maximum yield) was established for all genotypes, and significant variation was seen among the genotypes for fresh and dry biomass production. The later maturity genotypes, including the photo-period sensitive and modified photo-period sensitive type sorghums, produced the highest yields (up to 24 dry Mg/ha). Compositional analysis using near infrared reflectance spectroscopy (NIR) for lignin, hemicellulose, and cellulose was performed on a dry matter basis for the optimal harvest window for each genotype. Significant differences were seen in 2009 between the genotypes for lignin, hemicellulose, cellulose, ash and protein; with the earlier genotypes having higher percentage of lignin, and the later genotypes having lower percentages of lignin. Genotype x Environment interactions were also seen, and show the significance that rainfall can have. Based on this research, grain sorghum could be harvested first, followed by photo-period insensitive forage varieties, then moderately photo-period sensitive forage varieties followed by dedicated bioenergy sorghums (that are full photo-period sensitive), allowing for a more constant supply of feedstock to processing plants. Sweet sorghums would also allow the end user to obtain biomass when needed, however these types of sorghum may be much better suited to a different end application (i.e. crushing the stalks to obtain the juice).

The majority of biofuels are produced from corn and grain. The drawback to these sources of biofuels is the vast amount of cultivated land needed to produce substantial amounts of biofuel, potentially increasing the price of food and livestock products. Mesquite trees, a type of woody plant, are a proven source of bioenergy feedstock found on semi-arid lands. The overall objectives of this study were to develop algorithms for determining woody plant biomass on rangelands in Texas at plot-level using terrestrial lidar and at the local scale by integrating reference biomass and multispectral imagery. Terrestrial lidar offers a more efficient method for estimating biomass than traditional field measurements. Variables from the terrestrial lidar point cloud were compared to ground measurements of biomass to find a best fitting regression model. Two processing methods were investigated for analyzing the lidar point cloud data, namely: 1) percentile height statistics and 2) a height bin approach. Regression models were developed for variables obtained through each processing technique for estimating woody plant, above-ground biomass. Regression models were able to explain 81 percent and 77 percent of the variance associated with the aboveground biomass using percentile height statistics and height bins, respectively. The aboveground biomass map was generated by using the cokriging interpolation method with NDVI and ground biomass data. According to cross-validation, ordinary cokriging estimated biomass accurately (R^2 = 0.99). The results of this study revealed that terrestrial lidar can be used to accurately and efficiently estimate the aboveground biomass of mesquite trees in a semi-arid environment at plot level. Moreover, spatial interpolation techniques proved useful in scaling up biomass estimates to local scale.

Several species of fishes have been used for cage culture in Taiwan, including cobia, brown croaker, red drum, grouper, red seabream, emperor and snapper. Roughly speaking, the main factors determining the choice of the target species are mainly the selling price deleting the production cost. Different species have different biological characteristics that affect the economical performance. Included were specific growth rates, death or survival within cultural period, and efficiency in food conversion, etc.. By employing and modified the so-called Biomass model used in fishery biology (Kings, 1995), this research integrates the above factors into one single spreadsheet for each individual species, allowing for systematic observation of the continuous change in level of production (in terms of biomass). Through the culturing period, degrade in number was gradually offset by the gain in averaged body weights until a maximum value is reached before going downhill. This gives rise to the optimal solution of yield with the respective culturing period thus required. The results for different species were further compared in terms of expected investment and return by the end of the production. Results from this study showed that cobia has more advantage (in terms of biomass, biovalue and return on investment) than others as the prior choice under the current situation. Basic information for this study included the value of natural mortality, length-and-weigh relationship and the growth equation of the target species. The system was programmed under the EXCEL-Spreadsheet system of the Microsoft Inc. In the future other species of fishes may also be tested as possible candidates for cage culture. The program could also expected to serve as an auxiliary tool in education and fishery extension services.

Global energy demands combined with environmental restrictions are fueling a move to alternative energy sources. Biofuels are formed from biomass; the MixAlco process is one such method. In this work, food scraps are explored as a potential feedstock to the MixAlco process. Batch fermentation with various temperatures, buffers, and pH control methods elucidated the behavior of food scraps during fermentation. The pH and reactor configuration were limiting factors when maximizing production. A fermentor was developed and tested with constant pH control. This resulted in elevated concentration (100 g/L) and selectivity (82%) of desired products. The fermentation resulted in elevated concentrations, but low conversion of solids. The undigested material may serve as a nutrient source for fermenting lignocellulosic feedstocks. Combining various nutrient sources with lignocellulose, such as bagasse, resulted in additional production and further conversion. Multiple nutrient sources were tested resulting in total acid concentration ranging from 20.2 to 34.5 g/L.

Thesis (Ph. D.)--Oregon State University, 2003. / Typescript (photocopy). Includes bibliographical references (leaves 133-142). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references (leaves 212-220). Available also in a digital version from Dissertation Abstracts.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 240-244). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 240-244). Also available on the Internet.

Processing of lignocellulosic biomass for transportation fuels and other biocommodities in integrated biorefineries has been proposed as the future for emerging sustainable economies. Currently bioprocessing strategies are all multi-step processes involving extensive physicochemical pretreatments and costly amounts of exogenous enzyme addition. Consolidated bioprocessing (CBP), or direct microbial conversion, is a strategy that combines all the stages of production into one step, thus avoiding the use of expensive pretreatments and exogenous enzymes that reduce the economic viability of the products produced. With a growing trend towards increased consolidation, most of the reported work on CBP has been conducted with soluble sugars or commercial reagent grade cellulose. For CBP to become practical fermentative guidelines with native feedstocks and purified cellulose need to be delineated through specific substrate characterization as it relates to possible industrial fermentation. By carefully reviewing the fundamentals of biomass pretreatments for CBP, a comparative assessment of the fermentability of non-food agricultural residue and processed biomass was conducted with Clostridium thermocellum DSMZ 1237. Cell growth, and both gaseous and liquid fermentation end-product profiles of C. thermocellum as a CBP processing candidate was characterised. Batch fermentation experiments to investigate the effect of cellulose content, pretreatment, and substrate concentration, revealed that higher yields were correlated with higher cellulose content. Pretreatment of native substrates that increased access of the bacterial cells and enzymes to cellulose chains in the biomass substrate were key parameters that determined the overall bioconversion of a given feedstock to end-products. The contribution of amorphous cellulose (CAC) in different biomass substrates subjected to the same pretreatment conditions was identified as a novel factor that contributed to differences in bioconversion and end-product synthesis patterns. Although the overall yield of end products was low following bioaugmentation with exogenous glycosyl hydrolases from free-enzyme systems and cellulosome extracts. Treatment of biomass substrates with glycosyl hydrolase enzymes was observed to increase the rate of bioconversion of native feedstocks in biphasic manner during fermentation with C. thermocellum. A “quotient of accessibility” was identified as a feedstock agnostic guideline for biomass digestibility. / October 2015

Sustainable algae biofuel production is rising in demand, and the need to establish an efficient and proper algae harvesting method is extremely essential. Membrane filtration technology seems to be the most promising as a solid-liquid separation process. However, fouling seems to be the major problem for membranes. There is limited research on how to solve the problem of fouling, and cake buildup inside the membranes. A novel membrane design is required to solve the problem of fouling and cake buildup inside the membranes. The objective of this research is to construct a novel two way membrane design for algae biomass harvesting and water recycling. The methods used include culturing algae species, filtering them through the membrane module, and sample analysis for determining the water quality. The results show that the present filtration model had no fouling, or cake buildup as opposed to the previous filtration model. The present model permeate has a very low optical density of 0.007 absorbance at 750 nanometers. This result shows that permeate is completely devoid of algae.