scholarly journals Advanced Hardwood Biofuels Northwest: Commercialization Challenges for the Renewable Aviation Fuel Industry

2019 ◽  
Vol 9 (21) ◽  
pp. 4644 ◽  
Author(s):  
Brian J. Stanton ◽  
Richard R. Gustafson
Keyword(s):  
Consolidated Bioprocessing ◽  
Hybrid Poplar ◽  
Biofuel Production ◽  
Aviation Fuel ◽  
Jet Fuels ◽  
Cellulosic Biofuels ◽  
The North ◽  
Fuel Industry ◽  
Private Financing ◽  
Returns On Investment

A bioenergy summit was organized by Advanced Hardwood Biofuels Northwest (AHB) to debate the barriers to the commercialization of a hybrid poplar biofuels industry for the alternative jet fuels market from the perspective of five years of AHB research and development and two recent surveys of the North American cellulosic biofuels industry. The summit showed that: (1) Growing and converting poplar feedstock to aviation fuels is technically sound, (2) an adequate land base encompassing 6.03 and 12.86 million respective hectares of croplands and rangelands is potentially available for poplar feedstock production, (3) biofuel production is accompanied by a global warming potential that meets the threshold 60% reduction mandated for advanced renewable fuels but (4) the main obstruction to achieving a workable poplar aviation fuels market is making the price competitive with conventional jet fuels. Returns on investment into biomass farms and biorefineries are therefore insufficient to attract private-sector capital the fact notwithstanding that the demand for a reliable and sustainable supply of environmentally well-graded biofuels for civilian and military aviation is clear. Eleven key findings and recommendations are presented as a guide to a strategic plan for a renewed pathway to poplar alternative jet fuels production based upon co-products, refinery co-location with existing industries, monetization of ecosystem services, public-private financing, and researching more efficient and lower-costs conversion methods such as consolidated bioprocessing.

scholarly journals Cellulosic biofuel production using emulsified simultaneous saccharification and fermentation (eSSF) with conventional and thermotolerant yeasts

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Shannon M. Hoffman ◽  
Maria Alvarez ◽  
Gilad Alfassi ◽  
Dmitry M. Rein ◽  
Sergio Garcia-Echauri ◽  
...  
Keyword(s):  
Simultaneous Saccharification And Fermentation ◽  
Agricultural Waste ◽  
Biofuel Production ◽  
Cellulosic Biofuels ◽  
Processing Times ◽  
Cellulosic Biofuel ◽  
Thermotolerant Yeasts ◽  
Rapid Hydrolysis ◽  
Dedicated Energy Crops ◽  
Simultaneous Saccharification

Abstract Background Future expansion of corn-derived ethanol raises concerns of sustainability and competition with the food industry. Therefore, cellulosic biofuels derived from agricultural waste and dedicated energy crops are necessary. To date, slow and incomplete saccharification as well as high enzyme costs have hindered the economic viability of cellulosic biofuels, and while approaches like simultaneous saccharification and fermentation (SSF) and the use of thermotolerant microorganisms can enhance production, further improvements are needed. Cellulosic emulsions have been shown to enhance saccharification by increasing enzyme contact with cellulose fibers. In this study, we use these emulsions to develop an emulsified SSF (eSSF) process for rapid and efficient cellulosic biofuel production and make a direct three-way comparison of ethanol production between S. cerevisiae, O. polymorpha, and K. marxianus in glucose and cellulosic media at different temperatures. Results In this work, we show that cellulosic emulsions hydrolyze rapidly at temperatures tolerable to yeast, reaching up to 40-fold higher conversion in the first hour compared to microcrystalline cellulose (MCC). To evaluate suitable conditions for the eSSF process, we explored the upper temperature limits for the thermotolerant yeasts Kluyveromyces marxianus and Ogataea polymorpha, as well as Saccharomyces cerevisiae, and observed robust fermentation at up to 46, 50, and 42 °C for each yeast, respectively. We show that the eSSF process reaches high ethanol titers in short processing times, and produces close to theoretical yields at temperatures as low as 30 °C. Finally, we demonstrate the transferability of the eSSF technology to other products by producing the advanced biofuel isobutanol in a light-controlled eSSF using optogenetic regulators, resulting in up to fourfold higher titers relative to MCC SSF. Conclusions The eSSF process addresses the main challenges of cellulosic biofuel production by increasing saccharification rate at temperatures tolerable to yeast. The rapid hydrolysis of these emulsions at low temperatures permits fermentation using non-thermotolerant yeasts, short processing times, low enzyme loads, and makes it possible to extend the process to chemicals other than ethanol, such as isobutanol. This transferability establishes the eSSF process as a platform for the sustainable production of biofuels and chemicals as a whole.

scholarly journals Towards a new paradigm of “coopetitiveness” in emerging countries: Case of the Algerian Entrepreneurial Ecosystems

2019 ◽  
Vol 7 (1) ◽  
pp. 67-86
Author(s):  
Abdelkader Baaziz
Keyword(s):  
Value Chain ◽  
Emerging Countries ◽  
New Paradigm ◽  
Entrepreneurial Ecosystems ◽  
The North ◽  
Quintuple Helix ◽  
Multidisciplinary Working ◽  
The Creation ◽  
Individual Success ◽  
Private Financing

The main aim of this paper is to propose thinking tracks of Entrepreneurial Ecosystems based on a “Quintuple Helix” approach that overcomes the competitive partitions by founding a paradigm of “coopetition” and “coopetitiveness” through the “intelligent specialization” with a strong societal and economic impact. Indeed, the dominant vision in most of emerging countries calls the relationship between Entrepreneurial Ecosystems and their actors, exclusively in terms of competitiveness aspects by reproducing identically the North-American models unlinked to the environmental dissimilarities, such as entrepreneurial culture. However, it is important to enquiring about the spatiotemporal adaptability of this model in the emerging countries contexts, particularly through its uninhibited relationship to the concepts of individual success and failure as well as the ecosystems running based mainly on private financing from business angels, crowdfunding and venture capital investors. While the creation of a startup is administratively facilitated, the uncertainties of the environment put its sustainability in a severe test. The causes are numerous, we cite among others, the difficulty of these startups to fit into a multidisciplinary working mode, hence the necessity to integrate them in the value chain of an ecosystem where they answer efficiently to mutualized and specific RD needs. That's why we propose to identify the main barriers to open innovation as well as the catalysts enabling the creation of the integrative entrepreneurial ecosystems. By borrowing the paradigm of the city, we highlight the “urbanized” ecosystem made up of “useful” and “specialized” blocks, integrated in the value chain of this ecosystem. We will show the viability of the proposed tracks through many cases of economic, societal and academic actions undertaken in Algeria in order to setting up a favorable environment of integrative entrepreneurial ecosystems.

An Ignition Delay Study of Category A and C Aviation Fuel

2015 ◽  
Author(s):  
Kyungwook Min ◽  
Daniel Valco ◽  
Anna Oldani ◽  
Tonghun Lee
Keyword(s):  
Ignition Delay ◽  
Cetane Number ◽  
Test Chamber ◽  
Combustion Characteristics ◽  
Aviation Fuel ◽  
Jet Fuels ◽  
Fuel Blend ◽  
Auto Ignition ◽  
Alternative Aviation Fuels ◽  
Pressure Trace

Ignition delay of category A and C alternative aviation fuels have been investigated using a rapid compression machine (RCM). Newly introduced alternative jet fuels are not yet comprehensively understood in their combustion characteristics. Two of the category C fuels that will be primarily investigated in this study are Amyris Farnesane and Gevo Jet Fuel Blend. Amyris direct sugar to hydrocarbon (DSHC) fuel (POSF 10370) come from direct fermentation of bio feedstock sugar. Amyris DSHC is mainly composed of 2,6,10-trymethly dodecane, or farnesane. Gevo jet blend stock fuel is alcohol to jet (ATJ) fuel (POSF 10262) produced from bio derived butanol. Gevo jet blend stock is composed with iso-dodecane and iso-cetane, and has significantly low derived cetane number of 15. The experimental results are compared to combustion characteristics of conventional jet A fuels, including JP-8. Ignition delay, the important factor of auto ignition characteristic, is evaluated from pressure trace measured from the RCM at University of Illinois, Urbana-Champaign. The measurements are made at compressed pressure 20bar, intermediate and low compressed temperature, and equivalence ratio of unity and below. Direct test chamber charge method is used due to its reliable reproducibility of results. Compared to category A fuels, different combustion characteristics has been observed from category C fuels due to their irregular chemical composition.

scholarly journals Yeast Surface Display of Trifunctional Minicellulosomes for Simultaneous Saccharification and Fermentation of Cellulose to Ethanol

2009 ◽  
Vol 76 (4) ◽  
pp. 1251-1260 ◽  
Author(s):  
Fei Wen ◽  
Jie Sun ◽  
Huimin Zhao
Keyword(s):  
Cell Surface ◽  
Consolidated Bioprocessing ◽  
Surface Display ◽  
Cellulose Hydrolysis ◽  
Cellulase Production ◽  
Single Step ◽  
Yeast Surface Display ◽  
Biofuel Production ◽  
Yeast Cells ◽  
Recombinant Yeast Strain

ABSTRACT By combining cellulase production, cellulose hydrolysis, and sugar fermentation into a single step, consolidated bioprocessing (CBP) represents a promising technology for biofuel production. Here we report engineering of Saccharomyces cerevisiae strains displaying a series of uni-, bi-, and trifunctional minicellulosomes. These minicellulosomes consist of (i) a miniscaffoldin containing a cellulose-binding domain and three cohesin modules, which was tethered to the cell surface through the yeast a-agglutinin adhesion receptor, and (ii) up to three types of cellulases, an endoglucanase, a cellobiohydrolase, and a β-glucosidase, each bearing a C-terminal dockerin. Cell surface assembly of the minicellulosomes was dependent on expression of the miniscaffoldin, indicating that formation of the complex was dictated by the high-affinity interactions between cohesins and dockerins. Compared to the unifunctional and bifunctional minicellulosomes, the quaternary trifunctional complexes showed enhanced enzyme-enzyme synergy and enzyme proximity synergy. More importantly, surface display of the trifunctional minicellulosomes gave yeast cells the ability to simultaneously break down and ferment phosphoric acid-swollen cellulose to ethanol with a titer of ∼1.8 g/liter. To our knowledge, this is the first report of a recombinant yeast strain capable of producing cell-associated trifunctional minicellulosomes. The strain reported here represents a useful engineering platform for developing CBP-enabling microorganisms and elucidating principles of cellulosome construction and mode of action.

scholarly journals Clostridium thermocellum as a Promising Source of Genetic Material for Designer Cellulosomes: An Overview

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 996
Author(s):  
Dung Minh Ha-Tran ◽  
Trinh Thi My Nguyen ◽  
Chieh-Chen Huang
Keyword(s):  
Clostridium Thermocellum ◽  
Plant Cell Wall ◽  
Plant Biomass ◽  
Consolidated Bioprocessing ◽  
Genetic Material ◽  
Economic Feasibility ◽  
Biofuel Production ◽  
Cellulolytic Bacterium ◽  
Microbial Conversion ◽  
Promising Source

Plant biomass-based biofuels have gradually substituted for conventional energy sources thanks to their obvious advantages, such as renewability, huge quantity, wide availability, economic feasibility, and sustainability. However, to make use of the large amount of carbon sources stored in the plant cell wall, robust cellulolytic microorganisms are highly demanded to efficiently disintegrate the recalcitrant intertwined cellulose fibers to release fermentable sugars for microbial conversion. The Gram-positive, thermophilic, cellulolytic bacterium Clostridium thermocellum possesses a cellulolytic multienzyme complex termed the cellulosome, which has been widely considered to be nature’s finest cellulolytic machinery, fascinating scientists as an auspicious source of saccharolytic enzymes for biomass-based biofuel production. Owing to the supra-modular characteristics of the C. thermocellum cellulosome architecture, the cellulosomal components, including cohesin, dockerin, scaffoldin protein, and the plentiful cellulolytic and hemicellulolytic enzymes have been widely used for constructing artificial cellulosomes for basic studies and industrial applications. In addition, as the well-known microbial workhorses are naïve to biomass deconstruction, several research groups have sought to transform them from non-cellulolytic microbes into consolidated bioprocessing-enabling microbes. This review aims to update and discuss the current progress in these mentioned issues, point out their limitations, and suggest some future directions.

Characteristics of Deposits in Gas Turbine Combustion Chambers Using Synthetic and Conventional Jet Fuels

2013 ◽  
Vol 135 (7) ◽  
Author(s):  
Greg Pucher ◽  
William Allan ◽  
Pierre Poitras
Keyword(s):  
Combustion Chamber ◽  
Gas Turbine ◽  
Alternative Fuels ◽  
Large Scale ◽  
Aviation Fuel ◽  
Jet Fuels ◽  
Combustion Chambers ◽  
Fuel Blend ◽  
Synthetic Fuel ◽  
Camelina Oil

The synthetic fuel industry is poised to experience large-scale growth and profoundly affect current aviation fuel infrastructure. New candidate technologies, such as Camelina oil-derived synthetic fuel have been demonstrated to not only provide satisfactory quasi drop-in characteristics for conventional fuels, but in life cycle analysis studies have also been shown to potentially offer positive improvements relative to conventional feedstocks with respect to economic, environmental, and land use considerations. As part of a multiyear study at the Royal Military College of Canada to evaluate combustion related parameters of fuel additives and alternative fuels for gas turbine applications, a Camelina-derived synthetic fuel blend was assessed to determine potential combustion related benefits as compared to conventional and other synthetic blends. The Combustion Chamber Sector Rig (CCSR) which houses a Rolls Royce T-56-A-15 combustion section was utilized for the evaluation of emissions and deposits. Following combustion testing, several combustion system components, including the combustion chamber, fuel nozzle, and igniter plug were analyzed for relative levels of deposit build-up. As with other Fischer Tropsch derived synthetic fuels, there were positive benefits found with Camelina blends in terms of emissions performance and deposit production tendencies.

Experimental and Modeling Studies of the Oxidation of Surrogate Bio-Aviation Fuels

2012 ◽  
Vol 134 (4) ◽  
Author(s):  
Ida Shafagh ◽  
Kevin J. Hughes ◽  
Elena Catalanotti ◽  
Zhen Liu ◽  
Mohamed Pourkashanian ◽  
...  
Keyword(s):  
Experimental Studies ◽  
Acid Methyl Ester ◽  
Aviation Fuel ◽  
Aviation Industry ◽  
Jet Fuels ◽  
Product Analysis ◽  
Surrogate Fuels ◽  
Laser Induced Fluorescence Detection ◽  
Flame Burner ◽  
Oxidation Chemistry

Jet fuels currently in use in the aviation industry are exclusively kerosene-based. However, potential problems regarding security of supply, climate change, and increasing cost are becoming more significant, exacerbated by the rapidly growing demand from the aviation sector. Biofuels are considered one of the most suitable alternatives to petrochemical-based fuels in the aviation industry in the short to medium term, since blends of biofuel and kerosene provide a good balance of properties currently required from an aviation fuel. Experimental studies at a variety of stoichiometries using a flat flame burner with kerosene and kerosene/biofuel blends have been performed with product analysis by gas sampling and laser-induced fluorescence detection of OH, CO, and CO2. These studies have been complemented by modeling using the PREMIX module of Chemkin to provide insights into and to validate combined models describing the oxidation chemistry of surrogate fuels depicting kerosene, fatty acid methyl ester biofuels, and Fischer-Tropsch derived fuels. Sensitivity analysis has identified important reactions within these schemes, which, where appropriate, have been investigated by molecular modeling techniques available within Gaussian 03.

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