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Full-Text Articles in Life Sciences

Low Moisture Anhydrous Ammonia (Lmaa) Pretreatment Of Lignocellulosic Biomass And Assessments For Biobutanol Production, Nazira Binti Mahmud Jan 2019

Low Moisture Anhydrous Ammonia (Lmaa) Pretreatment Of Lignocellulosic Biomass And Assessments For Biobutanol Production, Nazira Binti Mahmud

Graduate Theses and Dissertations

Low-value biomass materials such as processing co-products and agricultural wastes possess abundant potential in value-added products production. The effort for utilization of these materials, especially as the substrate for fermentation process was limited by the low availability of fermentable sugar. This is due to the presence of lignin and hemicellulose in biomass structure, which entails appropriate pretreatment procedure to be conducted to expose the cellulose for the enzymatic reaction. Alkali-based pretreatments offer the attractive benefit of low inhibitor compound production. In this study, low moisture anhydrous ammonia (LMAA) pretreatment was conducted on selected biomass. Anhydrous ammonia, which is a gaseous ...


Autohydrolysis Pretreatment Of Mixed Lignocellulosic Biomass, Claudio Lira Jun 2018

Autohydrolysis Pretreatment Of Mixed Lignocellulosic Biomass, Claudio Lira

Electronic Thesis and Dissertation Repository

Lignocellulosic biomass, such as agricultural and forestry residues, can be transformed into valuable fuels and chemicals. However, the high cost of feedstock handling and the complex nature of cellulosic biomass processing and conversion remain two major challenges in biorefineries. This thesis aims to tackle these challenges by assessing the transformation of multi-feedstock using autohydrolysis pretreatment.

Corn cobs and stover (residues from corn processing), poplar chips (forestry residue), bagasse and wheat straw (agricultural residues) are abundant and often under-utilized cellulosic residues. These feedstocks were used to investigate the effects of biomass characteristics on the composition of the autohydrolysis pretreatment products. Moreover ...


Efficient Dehydration And Recovery Of Ionic Liquid After Lignocellulosic Processing Using Pervaporation, Jian Sun, Jian Shi, N. V. S. N. Murthy Konda, Dan Campos, Dajiang Liu, Stuart Nemser, Julia Shamshina, Tanmoy Dutta, Paula Berton, Gabriela Gurau, Robin D. Rogers, Blake A. Simmons, Seema Singh Jun 2017

Efficient Dehydration And Recovery Of Ionic Liquid After Lignocellulosic Processing Using Pervaporation, Jian Sun, Jian Shi, N. V. S. N. Murthy Konda, Dan Campos, Dajiang Liu, Stuart Nemser, Julia Shamshina, Tanmoy Dutta, Paula Berton, Gabriela Gurau, Robin D. Rogers, Blake A. Simmons, Seema Singh

Biosystems and Agricultural Engineering Faculty Publications

Background: Biomass pretreatment using certain ionic liquids (ILs) is very efficient, generally producing a substrate that is amenable to saccharification with fermentable sugar yields approaching theoretical limits. Although promising, several challenges must be addressed before an IL pretreatment technology can become commercially viable. One of the most significant challenges is the affordable and scalable recovery and recycle of the IL itself. Pervaporation (PV) is a highly selective and scalable membrane separation process for quantitatively recovering volatile solutes or solvents directly from non-volatile solvents that could prove more versatile for IL dehydration.

Results: We evaluated a commercially available PV system for ...


Optimization Of Extraction Parameters For Quantification Of Fermentation Volatile By‐Products In Industrial Ethanol With Solid‐Phase Microextraction And Gas Chromatography, Shinnosuke Onuki, Jacek A. Koziel, William S. Jenks, Lingshuang Cai, Somchai Rice, Johannes Van Leeuwen Jan 2016

Optimization Of Extraction Parameters For Quantification Of Fermentation Volatile By‐Products In Industrial Ethanol With Solid‐Phase Microextraction And Gas Chromatography, Shinnosuke Onuki, Jacek A. Koziel, William S. Jenks, Lingshuang Cai, Somchai Rice, Johannes Van Leeuwen

Agricultural and Biosystems Engineering Publications

The rapid growth of the biofuels industry resulted in new research needs in chemical analysis. Methods for screening and quantification of impurities resulting from changes in feedstock, process and purification are needed. Direct sample injection methods are often not sensitive for lower concentrations. This research, developed an analytical method to simultaneously quantify fermentation volatile by‐products in industrial corn‐based ethanol. These include acetaldehyde, ethyl vinyl ether, 1,1‐diethoxyethane, isoamyl alcohol, isoamyl acetate, styrene, 2‐pentylfuran, ethyl hexanoate, ethyl octanoate, and ethyl decanoate. Headspace solid‐phase microextraction (SPME) coupled with gas chromatography–mass spectrometry (GC–MS) and GC‐FID ...


The Bifunctional Alcohol And Aldehyde Dehydrogenase Gene, Adhe, Is Necessary For Ethanol Production In Clostridium Thermocellum And Thermoanaerobacterium Saccharolyticum, Jonathan Lo, Tianyong Zheng, Shuen Hon, Daniel G. Olson, Lee Lynd Feb 2015

The Bifunctional Alcohol And Aldehyde Dehydrogenase Gene, Adhe, Is Necessary For Ethanol Production In Clostridium Thermocellum And Thermoanaerobacterium Saccharolyticum, Jonathan Lo, Tianyong Zheng, Shuen Hon, Daniel G. Olson, Lee Lynd

Open Dartmouth: Peer-reviewed articles by Dartmouth faculty

Thermoanaerobacterium saccharolyticum and Clostridium thermocellum are anaerobic thermophilic bacteria being investigated for their ability to produce biofuels from plant biomass. The bifunctional alcohol and aldehyde dehydrogenase gene, adhE, is present in these bacteria and has been known to be important for ethanol formation in other anaerobic alcohol producers. This study explores the inactivation of the adhE gene in C. thermocellum and T. saccharolyticum. Deletion of adhE reduced ethanol production by >95% in both T. saccharolyticum and C. thermocellum, confirming that adhE is necessary for ethanol formation in both organisms. In both adhE deletion strains, fermentation products shifted from ethanol to ...


Economic And Environmental Analysis Of Farm-Scale Integrated Ethanol And Biodiesel Production Using Locally-Available Biomass, Bailley A. Richardson, Patrick J. Benson, Kurt A. Rosentrater Jul 2014

Economic And Environmental Analysis Of Farm-Scale Integrated Ethanol And Biodiesel Production Using Locally-Available Biomass, Bailley A. Richardson, Patrick J. Benson, Kurt A. Rosentrater

Agricultural and Biosystems Engineering Conference Proceedings and Presentations

With increased technology and economic opportunities, demand for energy and fuels in developing countries is growing exponentially to run processes and improve lifestyles, but rural areas may not have access. It is thus important to identify possible sources of energy for developing rural areas, especially those sources which are renewable and locally produced. The objective of this study was to develop a computer model to assess the viability of developing integrated biofuel production systems using biomass materials specific to Mozambique and India. The models considered various system capacities and production scenarios. Estimates of processing costs, along with other economic factors ...


Characterization Of Genetically Modified High Biomass Producing Tobacco Plant, Pankaj Singh Kuhar Jul 2014

Characterization Of Genetically Modified High Biomass Producing Tobacco Plant, Pankaj Singh Kuhar

Biological Systems Engineering--Dissertations, Theses, and Student Research

Global warming and peak oil has clouded our energy security. In light of this situation, bioethanol as emerged as one of the most amenable solutions to the problem. However bioethanol has its own shortcomings and transgenics seem imperative to exploit its full potential. A high biomass producing line in transgenic tobacco (Nicotiana tabacum cv. Xanthi) was identified during a routine genetic transformation, termed giant recombinant (GR). To characterize the phenotype of the giant line, growth rate and lignocellulosic composition was analyzed relative to the non-transgenic control line. The GR line accounted for 240% more biomass than the untransformed line within ...


Comparative Efficiency And Driving Range Of Light- And Heavy-Duty Vehicles Powered With Biomass Energy Stored In Liquid Fuels Or Batteries, Mark Laser, Lee R. R. Lynd Mar 2014

Comparative Efficiency And Driving Range Of Light- And Heavy-Duty Vehicles Powered With Biomass Energy Stored In Liquid Fuels Or Batteries, Mark Laser, Lee R. R. Lynd

Open Dartmouth: Peer-reviewed articles by Dartmouth faculty

This study addresses the question, "When using cellulosic biomass for vehicular transportation, which field-to-wheels pathway is more efficient: that using biofuels or that using bioelectricity?" In considering the question, the level of assumed technological maturity significantly affects the comparison, as does the intended transportation application. Results from the analysis indicate that for light-duty vehicles, over ranges typical in the United States today (e.g., 560-820 miles), field-to-wheels performance is similar, with some scenarios showing biofuel to be more efficient, and others indicating the two pathways to be essentially the same. Over the current range of heavy-duty vehicles, the field-to-wheels efficiency ...


The Effect Of Process Variables On Pyrolysis In A Freefall Reactor, Preston Gable Jan 2014

The Effect Of Process Variables On Pyrolysis In A Freefall Reactor, Preston Gable

Graduate Theses and Dissertations

The focus of this work is to test variables of fast pyrolysis conditions in a free fall reactor in order to better understand their impact on pyrolysis products, specifically optimization of bio-oil yields. In the first study, a design of experiments was performed and products were analyzed to evaluate the effects of temperature, sweep gas flow rates, and particle heating time, on bio-oil yields. This study proved particle heating time to be a very important variable effecting bio-oil yields, and that a heating time of greater than the traditionally assumed two seconds must be achieved in order to optimize yields ...


Techno-Economic Modeling Of A Degummed Soybean Oil Biorefinery In 2005 & 2012, Bailley A. Richardson, Kurt A. Rosentrater Jul 2013

Techno-Economic Modeling Of A Degummed Soybean Oil Biorefinery In 2005 & 2012, Bailley A. Richardson, Kurt A. Rosentrater

Agricultural and Biosystems Engineering Conference Proceedings and Presentations

As the biofuels industry expands, it is important to identify and quantize potential capital, operational, material, and utility costs, as well as possible sales prices for the biofuels and coproducts. Many industries use computer simulation programs for this function, as well as to see how using different operations can affect the overall production at the plant. The objective of this project was to determine how various operation scenarios affected capital, operational, material, and utility costs of a biodiesel biorefinery. These costs were examined using a techno-economic modeling program for a degummed soybean oil plant. It was clear after seeing economic ...


Some Properties Of Evolving Distillers Dried Grains With Solubles (Ddgs) In 2012, Weitao Zhang, Kurt A. Rosentrater Jul 2013

Some Properties Of Evolving Distillers Dried Grains With Solubles (Ddgs) In 2012, Weitao Zhang, Kurt A. Rosentrater

Agricultural and Biosystems Engineering Conference Proceedings and Presentations

With the rapid development of the ethanol industry, various research on distillers dried grains with solubles (DDGS) as a main co-product from the ethanol industry has been done in recent years. However, related research about basic properties to DDGS lacks of comprehensiveness. This study examined 18 samples from 10 plants in Midwest area and utilized standard laboratory methods to measure a series of properties. Final results showed moisture content of 8.69% (w.b.), water activity of 0.55, angle of repose of 48.04 º, geometric mean diameter (dgw) of 0.74 mm, geometric standard deviation (Sgw ...


Fractionation Of Distillers Dried Grains With Solubles (Ddgs) Through A Destoner, Weitao Zhang, Kurt A. Rosentrater Jul 2013

Fractionation Of Distillers Dried Grains With Solubles (Ddgs) Through A Destoner, Weitao Zhang, Kurt A. Rosentrater

Agricultural and Biosystems Engineering Conference Proceedings and Presentations

A destoner fractionation process was used to separate distillers dried grains with solubles (DDGS) into streams with various compositions. Results showed that destoner fractionation was somewhat efficient and effective. Runs with 8° angle and 27.5 percent air flow resulted in the highest value of protein and oil, which the light fraction had 28.15% protein, 10.50% oil, while the heavy fraction had 31.30% protein and 17.20% oil. Particle size distribution had a positive correlation coefficient (0.93) with oil parameters and a negative correlation coefficient (-0.96) with moisture parameters. Fiber had no relationship with particle ...


Developing Criteria For Evaluating The Sustainability Of Emerging Energy, Kurt A. Rosentrater, Elif Kongar Apr 2011

Developing Criteria For Evaluating The Sustainability Of Emerging Energy, Kurt A. Rosentrater, Elif Kongar

Kurt A. Rosentrater

Over the last decade, the interest in and production of biofuels has grown rapidly. Renewable transportation fuels can be produced from a variety of substrates, using various processing strategies. Feedstock preference and factory scale are geographic dependent. However, it is important to understand the implications of deploying these types of systems on a large scale, both throughout the U.S. as well as globally. To assess the sustainability of various biofuel options, it is crucial to evaluate their performance according to a number of attributes. This has been done using Life Cycle Assessment (LCA). Even so, comparisons among biofuel options ...


Modeling The Effects Of Pelleting On The Logistics Of Distillers Grains Shipping, Kurt A. Rosentrater, Elif Kongar Dec 2009

Modeling The Effects Of Pelleting On The Logistics Of Distillers Grains Shipping, Kurt A. Rosentrater, Elif Kongar

Kurt A. Rosentrater

The energy security needs of energy importing nations continue to escalate. It is clear that biofuels can help meet some of the increasing need for energy. Theoretically, these can be produced from a variety of biological materials, including agricultural residues (such as corn stover and wheat straw), perennial grasses, legumes, algae, and other biological materials. Currently, however, the most heavily utilized material is corn starch. Industrial fuel ethanol production in the US primarily uses corn, because it is readily converted into fuel at a relatively low cost compared to other biomass sources. The production of corn-based ethanol in the US ...


Costs Of Pelleting To Enhance The Logistics Of Distillers Grains Shipping, Kurt A. Rosentrater, Elif Kongar Oct 2009

Costs Of Pelleting To Enhance The Logistics Of Distillers Grains Shipping, Kurt A. Rosentrater, Elif Kongar

Kurt A. Rosentrater

Biofuels, especially corn-based ethanol, can help meet some of the increasing demand for transportation fuels. Currently, the most heavily utilized substrate is corn grain, which is readily converted into ethanol at a relatively low cost compared to other biomass sources. The production of ethanol in the U.S. has been dramatically increasing during the last several years; so too has the quantity of manufacturing coproducts. These nonfermentable residues are most often dried and sold as distillers dried grains with solubles – DDGS. Even though these materials are used to feed livestock in local markets, as the size of the industry continues ...


Modeling The Effects Of Value-Added Processing And Logistics Using Arena, Kurt A. Rosentrater, Elif Kongar Mar 2008

Modeling The Effects Of Value-Added Processing And Logistics Using Arena, Kurt A. Rosentrater, Elif Kongar

Kurt A. Rosentrater

Scarcity and cost of nonrenewable fossil fuels have been a growing focus of many energy-dependent nations, including the U.S., for the past couple of decades. There are mainly two ways to approach these problems: (1) reducing the energy dependency and/or (2) developing alternative means of energy production. Utilizing biofuels, which are renewable sources of energy, is a promising way to produce energy. But, as this industry grows, so too does the quantity of byproducts, which are known as DDGS. This paper discusses a model that has been developed to analyze the economic viability of DDGS processing, and includes ...


Biomass And Biofuels In Maine: Estimating Supplies For Expanding The Forest Products Industry, Jonathan Rubin, Kate Dickerson, Jacob Kavkewitz Nov 2007

Biomass And Biofuels In Maine: Estimating Supplies For Expanding The Forest Products Industry, Jonathan Rubin, Kate Dickerson, Jacob Kavkewitz

Energy & the Environment

This paper estimates the renewable energy potential of Maine’s forest resources, and how much energy these resources could potentially provide the state. Using the most recent state-specific data available, and a methodology similar to the Billion Tons Report, we find that ethanol production from Maine’s forest residues could potentially provide 18% of Maine’s transportation (gasoline) fuels with a fermentation wood to ethanol process. Making Fischer-Tropsch diesel (F-T diesel) using forest residues can replace 39% of Maine’s petro-diesel consumption. Actual levels of biofuels that can be produced will depend on conversion factors and forestry residue removals that ...


The Importance Of Emerging Biobased Industries To Engineering And Technology, Kurt A. Rosentrater, R. Balamuralikrishma Oct 2006

The Importance Of Emerging Biobased Industries To Engineering And Technology, Kurt A. Rosentrater, R. Balamuralikrishma

Kurt A. Rosentrater

Our society has developed an insatiable demand for energy and material goods. Historically, these needs have been met primarily by fossil fuels and other non-renewable raw materials. As environmental concerns grow, however, renewable resources are gaining increased attention. This paper examines the emergence and importance that biobased industries are increasingly beginning to play. A biobased enterprise, similar in concept to a traditional refinery or factory, utilizes conversion technologies to produce various products. These operations are rapidly increasing both in number as well as in capacity throughout this country, and are poised to add significantly to the nation’s energy and ...


The Global Relevance Of Bio-Based Industries To Engineering And Technology Education, Kurt A. Rosentrater, Radha Balamuralikrishma Jun 2006

The Global Relevance Of Bio-Based Industries To Engineering And Technology Education, Kurt A. Rosentrater, Radha Balamuralikrishma

Kurt A. Rosentrater

The society in which we live has developed an insatiable demand for energy and material goods. In particular, recent data reveals that the aggressive pursuit of improved standards of living in the highly populated countries of India and China has contributed to increased demand for fossil fuels, which has exacerbated the recent spike in energy costs. Historically, these needs have been met primarily by fossil fuels and other non-renewable raw materials. As environmental concerns grow, however, renewable resources are gaining increased attention. This paper examines the emergence and importance that bio-based industries are increasingly beginning to play. A bio-based enterprise ...


Expanding The Role Of Systems Modeling: Considering Byproduct Generation From Biofuel Production, Kurt A. Rosentrater Jan 2006

Expanding The Role Of Systems Modeling: Considering Byproduct Generation From Biofuel Production, Kurt A. Rosentrater

Kurt A. Rosentrater

The bioethanol industry has been experiencing rapid growth over the past several years, and is expected to continue to increase production for the foreseeable future. A vital component to the success of this industry is the sales and marketing of processing residues, which are primarily sold as dried distillers grains with solubles (DDGS). Systems modeling, a technique that has been used to predict future demand for bioethanol, can also be used to determine potential byproduct generation rates. This paper discusses the development of one such model, and presents predicted generation of DDGS as well as carbon dioxide emissions from this ...