scholarly journals Explaining the reductions in Brazilian sugarcane ethanol production costs: importance of technological change

GCB Bioenergy ◽  
2014 ◽  
Vol 7 (3) ◽  
pp. 468-478 ◽  
Author(s):  
Xiaoguang Chen ◽  
Hector M. Nuñez ◽  
Bing Xu
Keyword(s):  
Technological Change ◽  
Ethanol Production ◽  
Production Costs

scholarly journals Impact of Fractionation Process on the Technical and Economic Viability of Corn Dry Grind Ethanol Process

Processes ◽  
2019 ◽  
Vol 7 (9) ◽  
pp. 578 ◽  
Author(s):  
Kurambhatti ◽  
Kumar ◽  
Singh
Keyword(s):  
Ethanol Production ◽  
Simulation Models ◽  
Economic Feasibility ◽  
Production Costs ◽  
Internal Rate Of Return ◽  
Dry Fractionation ◽  
Fractionation Process ◽  
Dry Grind ◽  
Capital Costs ◽  
Ethanol Yields

Use of corn fractionation techniques in dry grind process increases the number of coproducts, enhances their quality and value, generates feedstock for cellulosic ethanol production and potentially increases profitability of the dry grind process. The aim of this study is to develop process simulation models for eight different wet and dry corn fractionation techniques recovering germ, pericarp fiber and/or endosperm fiber, and evaluate their techno-economic feasibility at the commercial scale. Ethanol yields for plants processing 1113.11 MT corn/day were 37.2 to 40 million gal for wet fractionation and 37.3 to 31.3 million gal for dry fractionation, compared to 40.2 million gal for conventional dry grind process. Capital costs were higher for wet fractionation processes ($92.85 to $97.38 million) in comparison to conventional ($83.95 million) and dry fractionation ($83.35 to $84.91 million) processes. Due to high value of coproducts, ethanol production costs in most fractionation processes ($1.29 to $1.35/gal) were lower than conventional ($1.36/gal) process. Internal rate of return for most of the wet (6.88 to 8.58%) and dry fractionation (6.45 to 7.04%) processes was higher than the conventional (6.39%) process. Wet fractionation process designed for germ and pericarp fiber recovery was most profitable among the processes.

Outlook for ethanol production costs in Brazil up to 2030, for different biomass crops and industrial technologies

2015 ◽  
Vol 147 ◽  
pp. 593-610 ◽  
Author(s):  
J.G.G. Jonker ◽  
F. van der Hilst ◽  
H.M. Junginger ◽  
O. Cavalett ◽  
M.F. Chagas ◽  
...  
Keyword(s):  
Ethanol Production ◽  
Production Costs ◽  
Biomass Crops

Ethanol Production from Different Substrates by a Flocculent Saccharomyces cerevisiae Strain

2009 ◽  
Vol 7 (1) ◽  
Author(s):  
José Duarte ◽  
Vera Lourenço ◽  
Belina Ribeiro ◽  
Maria Céu Saagua ◽  
Joana Pereira ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Ethanol Production ◽  
Yeast Strain ◽  
Fossil Fuels ◽  
Ethanol Yield ◽  
Corn Fiber ◽  
Production Costs ◽  
Raw Material ◽  
Continuous Reactor ◽  
Different Strains

During the last years there has been an increasing interest in using ethanol as a substitute for fossil fuels. The bioethanol used today is mainly produced from sugar cane and cereals, but reducing the production costs of ethanol is still crucial for a viable economic process. Cellulose from vegetable biomass will be the next cheap raw material for second generation fuel ethanol production and agricultural by-products with a low commercial value, as corn stover, corn fiber and cane bagasses would become an attractive feedstock for bioethanol production.In this study, different strains of Saccharomyces cerevisiae have been screened for the ability of bioethanol production. Yeasts were grown in a synthetic liquid medium containing sucrose in batch regime and the growth rates, ethanol and biomass productions were determined as well as their growth ability in cane molasses.The results indicate that a flocculent yeast, isolated in our lab and designated by strain F, was the most promising yeast strain among those tested for continuous ethanol production. This strain was isolated from corn hydrolysates, obtained from a Portuguese distillery facility (DVT, Torres Novas, Portugal) showing highest growth rate (0.49h-1), highest ethanol yield (0.35g/g) and high flocculation capacity.The study on ethanol production in continuous reactor process with the selected yeast strain (strain F) was made on sucrose and cane molasses at different dilution rates (0.05-0.42 h-1). A steady flocculating yeast fluidized bed reactor system was established allowing the functioning of the reactor for 1000 h. Data shows that when the dilution rate rose to 0.42h-1, the highest productivity (20g/Lh) was obtained attaining an ethanol concentration in the reactor of 47g/L for sucrose and molasses media.

scholarly journals Thermotolerant Yeast Strains Adapted by Laboratory Evolution Show Trade-Off at Ancestral Temperatures and Preadaptation to Other Stresses

mBio ◽  
2015 ◽  
Vol 6 (4) ◽  
Author(s):  
Luis Caspeta ◽  
Jens Nielsen
Keyword(s):  
Ethanol Production ◽  
Production Costs ◽  
Thermotolerant Yeast ◽  
Adaptive Laboratory Evolution ◽  
Genetic Changes ◽  
Laboratory Evolution ◽  
Trade Off ◽  
Thermal Niche ◽  
Production Processes ◽  
Yeast Strains

ABSTRACT A major challenge for the production of ethanol from biomass-derived feedstocks is to develop yeasts that can sustain growth under the variety of inhibitory conditions present in the production process, e.g., high osmolality, high ethanol titers, and/or elevated temperatures (≥40°C). Using adaptive laboratory evolution, we previously isolated seven Saccharomyces cerevisiae strains with improved growth at 40°C. Here, we show that genetic adaptations to high temperature caused a growth trade-off at ancestral temperatures, reduced cellular functions, and improved tolerance of other stresses. Thermotolerant yeast strains showed horizontal displacement of their thermal reaction norms to higher temperatures. Hence, their optimal and maximum growth temperatures increased by about 3°C, whereas they showed a growth trade-off at temperatures below 34°C. Computational analysis of the physical properties of proteins showed that the lethal temperature for yeast is around 49°C, as a large fraction of the yeast proteins denature above this temperature. Our analysis also indicated that the number of functions involved in controlling the growth rate decreased in the thermotolerant strains compared with the number in the ancestral strain. The latter is an advantageous attribute for acquiring thermotolerance and correlates with the reduction of yeast functions associated with loss of respiration capacity. This trait caused glycerol overproduction that was associated with the growth trade-off at ancestral temperatures. In combination with altered sterol composition of cellular membranes, glycerol overproduction was also associated with yeast osmotolerance and improved tolerance of high concentrations of glucose and ethanol. Our study shows that thermal adaptation of yeast is suitable for improving yeast resistance to inhibitory conditions found in industrial ethanol production processes. IMPORTANCE Yeast thermotolerance can significantly reduce the production costs of biomass conversion to ethanol. However, little information is available about the underlying genetic changes and physiological functions required for yeast thermotolerance. We recently revealed the genetic changes of thermotolerance in thermotolerant yeast strains (TTSs) generated through adaptive laboratory evolution. Here, we examined these TTSs’ physiology and computed their proteome stability over the entire thermal niche, as well as their preadaptation to other stresses. Using this approach, we showed that TTSs exhibited evolutionary trade-offs in the ancestral thermal niche, as well as reduced numbers of growth functions and preadaptation to other stresses found in ethanol production processes. This information will be useful for rational engineering of yeast thermotolerance for the production of biofuels and chemicals.

scholarly journals Current Trends in Bioethanol Production by Saccharomyces cerevisiae: Substrate, Inhibitor Reduction, Growth Variables, Coculture, and Immobilization

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Asmamaw Tesfaw ◽  
Fassil Assefa
Keyword(s):  
Ethanol Production ◽  
Cell Mass ◽  
Nitrogen Sources ◽  
Extraction Methods ◽  
Production Costs ◽  
Yeast Cells ◽  
Bulk Liquid ◽  
Fermentation Time ◽  
Wide Range ◽  
Substrate Inhibitor

Bioethanol is one of the most commonly used biofuels in transportation sector to reduce greenhouse gases. S. cerevisiae is the most employed yeast for ethanol production at industrial level though ethanol is produced by an array of other yeasts, bacteria, and fungi. This paper reviews the current and nonmolecular trends in ethanol production using S. cerevisiae. Ethanol has been produced from wide range of substrates such as molasses, starch based substrate, sweet sorghum cane extract, lignocellulose, and other wastes. The inhibitors in lignocellulosic hydrolysates can be reduced by repeated sequential fermentation, treatment with reducing agents and activated charcoal, overliming, anion exchanger, evaporation, enzymatic treatment with peroxidase and laccase, in situ detoxification by fermenting microbes, and different extraction methods. Coculturing S. cerevisiae with other yeasts or microbes is targeted to optimize ethanol production, shorten fermentation time, and reduce process cost. Immobilization of yeast cells has been considered as potential alternative for enhancing ethanol productivity, because immobilizing yeasts reduce risk of contamination, make the separation of cell mass from the bulk liquid easy, retain stability of cell activities, minimize production costs, enable biocatalyst recycling, reduce fermentation time, and protect the cells from inhibitors. The effects of growth variables of the yeast and supplementation of external nitrogen sources on ethanol optimization are also reviewed.

scholarly journals Novel ethanol production using biomass preprocessing to increase ethanol yield and reduce overall costs

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Danielle Uchimura Pascoli ◽  
Azra Suko ◽  
Rick Gustafson ◽  
Heidi L. Gough ◽  
Renata Bura
Keyword(s):  
Ethanol Production ◽  
Ethanol Yield ◽  
Liquid Fraction ◽  
Treatment Plant ◽  
Production Costs ◽  
Operating Costs ◽  
Base Case ◽  
Sugar Recovery ◽  
Recycled Water ◽  
New Process

Abstract Background Ethanol biorefineries need to lower their overall production costs to become economically feasible. Two strategies to achieve this are to reduce costs using cheaper feedstocks or to increase the ethanol production yield. Low-cost feedstocks usually have high non-structural components (NSC) content; therefore, a new process is necessary to accommodate these feedstocks and overcome the negative effects of NSC. This study developed a novel ethanol biorefinery process including a biomass preprocessing step that enabled the use of lower-cost feedstocks while improving ethanol production without detoxification (overliming). Two types of poplar feedstocks were used, low-quality whole-tree chips (WTC) and high-quality clean pulp chips (CPC), to determine if the proposed process is effective while using feedstocks with different NSC contents. Results Technical assessment showed that acidic preprocessing increased the monomeric sugar recovery of WTC from 73.2% (untreated) to 87.5% due to reduced buffering capacity of poplar, improved sugar solubilization during pretreatment, and better enzymatic hydrolysis conversion. Preprocessing alone significantly improved the fermentability of the liquid fraction from 1–2% to 49–56% for both feedstocks while overliming improved it to 45%. Consequently, it was proposed that preprocessing can substitute for the detoxification step. The economic assessment revealed that using poplar WTC via the new process increased annual ethanol production of 10.5 million liters when compared to using CPC via overliming (base case scenario). Also, savings in total operating costs were about $10 million per year when using cheaper poplar WTC instead of CPC, and using recycled water for preprocessing lowered its total operating costs by 45-fold. Conclusions The novel process developed in this study was successful in increasing ethanol production while decreasing overall costs, thus facilitating the feasibility of lignocellulosic ethanol biorefineries. Key factors to achieving this outcome included substituting overliming by preprocessing, enabling the use of lower-quality feedstock, increasing monomeric sugar recovery and ethanol fermentation yield, and using recycled water for preprocessing. In addition, preprocessing enabled the implementation of an evaporator-combustor downstream design, resulting in a low-loading waste stream that can be treated in a wastewater treatment plant with a simple configuration.

scholarly journals Novel ethanol production using biomass preprocessing to increase ethanol yield and reduce overall costs

2020 ◽  
Author(s):  
Danielle Uchimura Pascoli ◽  
Azra Suko ◽  
Rick Gustafson ◽  
Heidi Gough ◽  
Renata Bura
Keyword(s):  
Ethanol Production ◽  
Ethanol Yield ◽  
Liquid Fraction ◽  
Treatment Plant ◽  
Production Costs ◽  
Operating Costs ◽  
Base Case ◽  
Sugar Recovery ◽  
Recycled Water ◽  
New Process

Abstract Background: Ethanol biorefineries need to lower their overall production costs to become economically feasible. Two strategies to achieve this are to reduce costs by using cheaper feedstocks or to increase the ethanol production yield. Low-cost feedstocks usually have high non-structural components (NSC) content, therefore a new process is necessary to accommodate these feedstocks and overcome the negative effects of NSC. This study developed a novel ethanol biorefinery process including a biomass preprocessing step that enabled the use of lower-cost feedstocks while improving ethanol production without detoxification (overliming). Two types of poplar feedstocks were used, low-quality whole-tree chips (WTC) and high-quality clean pulp chips (CPC), to determine if the proposed process is effective while using feedstocks with different NSC contents.Results: Technical assessment showed that acidic preprocessing increased the monomeric sugar recovery of WTC from 73.2% (untreated) to 87.5% due to reduced buffering capacity of poplar, improved sugar solubilization during pretreatment, and better enzymatic hydrolysis conversion. Preprocessing alone significantly improved the fermentability of the liquid fraction from 1-2% to 49-56% for both feedstocks, while overliming improved it to 45%. Consequently, it was proposed that preprocessing can substitute for the detoxification step. The economic assessment revealed that using poplar WTC via the new process increased annual ethanol production of 10.5 million liters when compared to using CPC via overliming (base case scenario). Also, savings in total operating costs were about $10 million per year when using cheaper poplar WTC instead of CPC, and by using recycled water for preprocessing lowered its total operating costs by 45-fold.Conclusions: The novel process developed in this study was successful in increasing ethanol production while decreasing overall costs, thus facilitating the feasibility of lignocellulosic ethanol biorefineries. Key factors to achieving this outcome included substituting overliming by preprocessing, enabling the use of lower-quality feedstock, increasing monomeric sugar recovery and ethanol fermentation yield, and using recycled water for preprocessing. In addition, preprocessing enabled the implementation of an evaporator-combustor downstream design, resulting in a low-loading waste stream that can be treated in a wastewater treatment plant with a simple configuration.

scholarly journals SOME MARKET EFFECTS OF E-COMMERCE

2001 ◽  
Vol 46 (01) ◽  
pp. 49-62 ◽  
Author(s):  
JOHN FREEBAIRN
Keyword(s):  
Technological Change ◽  
Transaction Costs ◽  
Production Costs ◽  
Efficiency Gains ◽  
Market Structures ◽  
Market Effects ◽  
Static Models ◽  
Competitive Forces ◽  
Profit Incentives ◽  
Benefits And Costs

An important characteristic of E-commerce is that it is a form of technological change. The effects of E-commerce induced reductions in business production costs and on seller to buyer transaction costs are assessed. Comparative static models for different market structures are used to assess the effects of E-commerce on prices, quantities, aggregate efficiency gains, and the distribution of benefits and costs. Ultimately consumers are the principal beneficiaries via lower prices. Competitive forces and profit incentives induce firms to adopt cost reducing E-commerce technology.

Development of plant concepts for ethanol production from wheat and wheat straw

2013 ◽  
pp. 208-214 ◽  
Author(s):  
Arne Gröngröft ◽  
André Brosowski ◽  
Kathleen Meisel ◽  
Franziska Müller-Langer
Keyword(s):  
Greenhouse Gas ◽  
Ethanol Production ◽  
Ghg Emissions ◽  
Production Costs ◽  
Fresh Matter ◽  
Market Prices ◽  
Ethanol Plant ◽  
Plant Processing ◽  
Supply Costs ◽  
The Cost

Fuel ethanol produced from sugar and starch is to be complemented and eventually even replaced by ethanol produced from lignocellulose, in order to mitigate possible competition with the food sector. A first step towards this goal may be a combination of both feedstocks in one plant. This is topic of the presented study, whether synergies in lowering the production costs and greenhouse gas (GHG) emissions can be reached through combined processing was topic of the presented study. A greenfield straw ethanol plant, a wheat ethanol plant and an integrated plant, processing both wheat grain and straw were developed and compared regarding the resulting GHG emissions and production costs. Despite showing the best results with regard to greenhouse gas emissions, greenfield straw ethanol production is related to relatively high production costs. The wheat based ethanol plant again is associated with higher GHG emissions, but low production costs. By combining straw and wheat processing, resulting production costs of EUR651/m3 ethanol are at a level close to market prices, but the same mitigation potential as separate straw based ethanol cannot be reached. The low level of 16.1 g CO2-eq/MJ of straw based ethanol results mainly from the use of the agricultural residue as feedstock and the use of the internally produced lignin to ensure the steam supply. In the assessment of the production costs, feedstock costs are one of the most relevant parameters. Since straw prices are not available from market statistics, an assessment of Germany’s sustainable straw potential in a high spatial resolution has served to calculate straw supply costs. Depending on the exact location of the plant, a range of EUR50/t to EUR90/t (fresh matter) was found to be the cost for straw provision.

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