Investigation of the Feasibility and Feedstock Management Strategies of a Flexible Biomass to Ethanol Plant via Process Simulation

2009 ◽  
Author(s):  
Nannan Kou ◽  
Fu Zhao
Keyword(s):  
Ethanol Production ◽  
Alternative Energy ◽  
Feeding Rate ◽  
Ethanol Yield ◽  
Management Strategies ◽  
Chemical Conversion ◽  
Wood Chips ◽  
Production Model ◽  
Wide Range ◽  
Petroleum Oil

Current US transportation sector mainly relies on liquid hydrocarbon derived from petroleum oil and about 60% of the petroleum oil consumed is from areas where supply may be disturbed by regional instability. This has led to serious concerns on global warming and energy security. To address these issues, numerous alternative energy carriers have been proposed. Among them, second generation biofuel is one of the most promising technologies. Gasification based thermo-chemical conversion can utilize a wide range of biomass wastes and residues and bring flexibility to both feedstock and production sides of a plant, thus presents an attractive technical route. In this paper, a flexible feedstock thermo-chemical ethanol production process is investigated. This research focuses mainly on the evaluation of the feasibility of the process through numerical simulation. An existing thermo-chemical ethanol production model developed by NREL has been updated to handle the cases when different biomass feedstock and feedstock combinations are used. It is found that the ethanol yield is positively proportional to the feedstock feeding rate, while the total conversion efficiency is negatively proportional to the feeding rate. To demonstrate a feedstock management strategy, a plant located near a major city with a population of 200,000 and above is considered and MSW, legume straw and wood chips are selected as potential feedstock. Simulation results indicate that with wood chips as the backup feedstock the plant can be operated under extreme conditions when legume straw availability is significantly reduced without major equipment modification.

Aspen Plus Process Simulation of Flexible Feedstock Thermo-Chemical Ethanol Production

2009 ◽  
Author(s):  
Nannan Kou ◽  
Fu Zhao ◽  
Li Zhang
Keyword(s):  
Ethanol Production ◽  
Corn Stover ◽  
Alternative Energy ◽  
Feeding Rate ◽  
Ethanol Yield ◽  
Chemical Conversion ◽  
Liquid Hydrocarbon ◽  
Wood Chips ◽  
Production Model ◽  
Wide Range

Current US transportation sector mainly relies on liquid hydrocarbon derived from petroleum and about 60% of the petroleum consumed is from areas where supply may be disturbed by regional instability. This has led to serious concerns on global warming and energy security. To address these issues, numerous alternative energy carriers have been proposed. Among them, second generation biofuel is one of the most promising technologies. Gasification based thermo-chemical conversion can utilize a wide range of biomass wastes and residues and bring flexibility to both feedstock and production sides of a plan. Thus it presents an attractive technical route. In this paper, a flexible feedstock thermo-chemical ethanol production process is investigated. This research focuses mainly on the evaluation of the feasibility of the process through numerical simulation. An existing thermo-chemical ethanol production model developed by NREL has been updated to handle the cases when different biomass feedstock and feedstock combinations are used. It is found that the ethanol yield is positively linear proportional to the feedstock feeding rate, while the total conversion efficiency is negatively proportional to the feeding rate. To demonstrate a feedstock management strategy, a plant located near a major city with a population of 200,000 and above is considered and MSW, corn stover and wood chips are selected as potential feedstock. Simulation results indicate that with wood chips as the backup feedstock the plant can be operated under extreme conditions when corn stover availability is significantly reduced without major equipment modification.

Understanding Limited Use of Amplification in Infants and Children Who Are Hard of Hearing

2015 ◽  
Vol 25 (1) ◽  
pp. 15-23 ◽  
Author(s):  
Ryan W. McCreery ◽  
Elizabeth A. Walker ◽  
Meredith Spratford
Keyword(s):  
Hard Of Hearing ◽  
Hearing Aid ◽  
Management Strategies ◽  
Infants And Children ◽  
Future Research ◽  
Research Needs ◽  
Case Examples ◽  
Hearing Aid Use ◽  
Wide Range ◽  
In Infants And Children

The effectiveness of amplification for infants and children can be mediated by how much the child uses the device. Existing research suggests that establishing hearing aid use can be challenging. A wide range of factors can influence hearing aid use in children, including the child's age, degree of hearing loss, and socioeconomic status. Audiological interventions, including using validated prescriptive approaches and verification, performing on-going training and orientation, and communicating with caregivers about hearing aid use can also increase hearing aid use by infants and children. Case examples are used to highlight the factors that influence hearing aid use. Potential management strategies and future research needs are also discussed.

scholarly journals Trends in Molecular Diagnosis and Diversity Studies for Phytosanitary Regulated Xanthomonas

2021 ◽  
Vol 9 (4) ◽  
pp. 862
Author(s):  
Vittoria Catara ◽  
Jaime Cubero ◽  
Joël F. Pothier ◽  
Eran Bosis ◽  
Claude Bragard ◽  
...  
Keyword(s):  
Molecular Diagnosis ◽  
Bacterial Species ◽  
Management Strategies ◽  
Diagnostic Methods ◽  
Plant Diseases ◽  
Wild Plants ◽  
Future Climate Change ◽  
Climate Change Scenarios ◽  
Wide Range ◽  
Diversity Studies

Bacteria in the genus Xanthomonas infect a wide range of crops and wild plants, with most species responsible for plant diseases that have a global economic and environmental impact on the seed, plant, and food trade. Infections by Xanthomonas spp. cause a wide variety of non-specific symptoms, making their identification difficult. The coexistence of phylogenetically close strains, but drastically different in their phenotype, poses an added challenge to diagnosis. Data on future climate change scenarios predict an increase in the severity of epidemics and a geographical expansion of pathogens, increasing pressure on plant health services. In this context, the effectiveness of integrated disease management strategies strongly depends on the availability of rapid, sensitive, and specific diagnostic methods. The accumulation of genomic information in recent years has facilitated the identification of new DNA markers, a cornerstone for the development of more sensitive and specific methods. Nevertheless, the challenges that the taxonomic complexity of this genus represents in terms of diagnosis together with the fact that within the same bacterial species, groups of strains may interact with distinct host species demonstrate that there is still a long way to go. In this review, we describe and discuss the current molecular-based methods for the diagnosis and detection of regulated Xanthomonas, taxonomic and diversity studies in Xanthomonas and genomic approaches for molecular diagnosis.

scholarly journals Enzymatic Process for Cystoseira barbata Valorization: Ethanol Production and Additional By-Products

Processes ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 741
Author(s):  
Doinita-Roxana Cioroiu Tirpan ◽  
Ancaelena Eliza Sterpu ◽  
Claudia Irina Koncsag ◽  
Alina Georgiana Ciufu ◽  
Tănase Dobre
Keyword(s):  
Ethanol Production ◽  
Alcoholic Fermentation ◽  
Ethanol Yield ◽  
Product Yield ◽  
Liquid Ratio ◽  
Experimental Conditions ◽  
Factors Affecting ◽  
Cystoseira Barbata ◽  
Main Factors ◽  
Process Factors

The aim of this study is to evaluate the potential of dried Cystoseira barbata alga for ethanol production through alcoholic fermentation. The influence of the main factors affecting the fermentation are studied in the frame of a 23 factorial experimental plan. The main factors influencing the process are the fermentation temperature (t from 25 °C to 35 °C), the solid to liquid ratio (S/L from 0.040 g/g to 0.080 g/g), and the cellulase ratio (R from 8 U/g d.m to 16 U/g d.m.). The maximum volatile compounds yield of 0.2808 g/g d.m and ethanol yield of 0.0158 g/g d.m were favored by the following experimental conditions: process temperature of 35 °C, solid to liquid ratio of 0.0415, and enzyme ratio of 16 U/g d.m. A statistical model was used to correlate the product yield with the process factors. Additionally, 19 interesting bioactive compounds were found in the enzymatic hydrolysis and alcoholic fermentation broths which seem likely to maintain natural defence mechanisms against diseases and physical disorders.

scholarly journals Hemicellulosic Bioethanol Production from Fast-Growing Paulownia Biomass

Processes ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 173
Author(s):  
Elena Domínguez ◽  
Pablo G. del Río ◽  
Aloia Romaní ◽  
Gil Garrote ◽  
Lucília Domingues
Keyword(s):  
Ethanol Production ◽  
Ethanol Concentration ◽  
Ethanol Yield ◽  
Xylose Reductase ◽  
Energy Crop ◽  
Scheffersomyces Stipitis ◽  
Fractionation Process ◽  
Renewable Source ◽  
Fast Growing ◽  
Engineered Strain

In order to exploit a fast-growing Paulownia hardwood as an energy crop, a xylose-enriched hydrolysate was obtained in this work to increase the ethanol concentration using the hemicellulosic fraction, besides the already widely studied cellulosic fraction. For that, Paulownia elongata x fortunei was submitted to autohydrolysis treatment (210 °C or S0 of 4.08) for the xylan solubilization, mainly as xylooligosaccharides. Afterwards, sequential stages of acid hydrolysis, concentration, and detoxification were evaluated to obtain fermentable sugars. Thus, detoxified and non-detoxified hydrolysates (diluted or not) were fermented for ethanol production using a natural xylose-consuming yeast, Scheffersomyces stipitis CECT 1922, and an industrial Saccharomyces cerevisiae MEC1133 strain, metabolic engineered strain with the xylose reductase/xylitol dehydrogenase pathway. Results from fermentation assays showed that the engineered S. cerevisiae strain produced up to 14.2 g/L of ethanol (corresponding to 0.33 g/g of ethanol yield) using the non-detoxified hydrolysate. Nevertheless, the yeast S. stipitis reached similar values of ethanol, but only in the detoxified hydrolysate. Hence, the fermentation data prove the suitability and robustness of the engineered strain to ferment non-detoxified liquor, and the appropriateness of detoxification of liquor for the use of less robust yeast. In addition, the success of hemicellulose-to-ethanol production obtained in this work shows the Paulownia biomass as a suitable renewable source for ethanol production following a suitable fractionation process within a biorefinery approach.

scholarly journals Effects of Ultrasound on Fermentation of Glucose to Ethanol by Saccharomyces cerevisiae

Fermentation ◽  
2019 ◽  
Vol 5 (1) ◽  
pp. 16 ◽  
Author(s):  
Luis Huezo ◽  
Ajay Shah ◽  
Frederick Michel
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Mass Transfer ◽  
Glucose Uptake ◽  
Ethanol Production ◽  
Ethanol Yield ◽  
Biofuel Production ◽  
Inhibitory Effects ◽  
Negative Effects ◽  
Intraparticle Mass Transfer ◽  
Improve Mass Transfer

Previous studies have shown that pretreatment of corn slurries using ultrasound improves starch release and ethanol yield during biofuel production. However, studies on its effects on the mass transfer of substrates and products during fermentation have shown that it can have both beneficial and inhibitory effects. In this study, the effects of ultrasound on mass transfer limitations during fermentation were examined. Calculation of the external and intraparticle observable moduli under a range of conditions indicate that no external or intraparticle mass transfer limitations should exist for the mass transfer of glucose, ethanol, or carbon dioxide. Fermentations of glucose to ethanol using Saccharomyces cerevisiae were conducted at different ultrasound intensities to examine its effects on glucose uptake, ethanol production, and yeast population and viability. Four treatments were compared: direct ultrasound at intensities of 23 and 32 W/L, indirect ultrasound (1.4 W/L), and no-ultrasound. Direct and indirect ultrasound had negative effects on yeast performance and viability, and reduced the rates of glucose uptake and ethanol production. These results indicate that ultrasound during fermentation, at the levels applied, is inhibitory and not expected to improve mass transfer limitations.

Valuing Streamflow Forecasts in Centrally Controlled Power Systems

2021 ◽  
Author(s):  
Jordan Kern ◽  
Nathalie Voisin ◽  
Sean Turner ◽  
Hongxiang Yan ◽  
Konstantinos Oikonomou
Keyword(s):  
Power Systems ◽  
Electricity Markets ◽  
Management Strategies ◽  
Profit Maximization ◽  
Value Added ◽  
Marginal Value ◽  
Wide Range ◽  
Streamflow Forecasts ◽  
Hydropower Production ◽  
Bulk Power

<p>Given the wide range of institutional and market contexts in which hydroelectric dams are operated, determining the value added from improvements in hydrologic forecasts is a challenge. Many previous examples of hydrologic forecasts being used to optimize hydropower production strategies at dams focus on a single reservoir system or watershed, with a key assumption that the marginal value of hydropower production is exogenously-defined (dams are ‘price takers’ in markets for electricity that exhibit no market power). In some cases, this may accurately reflect current institutional boundaries and decision making processes. However, with increased attention being paid to how more coordinated grid management strategies, including management of hydropower assets, could facilitate deep integration of renewable energy, it is critical to understand how the use of improved hydrologic forecasts could produce wider grid-scale benefits, including  lower costs and emissions. In this study, we quantify the value of streamflow forecasts to a centralized power system operator in charge of coordinating sub-weekly operations of hydropower assets, using the Western U.S. as a case study. We propagate flow forecasts through realistic models of reservoir operations and models of bulk power systems/wholesale electricity markets. Our results shed light on how the value of flow forecasts to grid operations can vary across regions and power systems. They also highlight the potential for conflicts between firm-specific objectives (profit maximization) and system-wide objectives (minimization of costs and emissions) when determining value added from hydrologic forecasts.  </p>

scholarly journals Coping with abrupt environmental change: the impact of the coastal El Niño 2017 on artisanal fisheries and mariculture in North Peru

2018 ◽  
Vol 76 (4) ◽  
pp. 1122-1130 ◽  
Author(s):  
Lotta Clara Kluger ◽  
Sophia Kochalski ◽  
Arturo Aguirre-Velarde ◽  
Ivonne Vivar ◽  
Matthias Wolff
Keyword(s):  
El Niño ◽  
El Nino ◽  
Management Strategies ◽  
Small Scale ◽  
Artisanal Fisheries ◽  
Economic Activities ◽  
Economic Sectors ◽  
Wide Range ◽  
The Impact ◽  
Coastal El Niño

Abstract In February and March 2017, a coastal El Niño caused extraordinary heavy rains and a rise in water temperatures along the coast of northern Peru. In this work, we document the impacts of this phenomenon on the artisanal fisheries and the scallop aquaculture sector, both of which represent important socio-economic activities for the province of Sechura. Despite the perceived absence of effective disaster management and rehabilitation policies, resource users opted for a wide range of different adaptation strategies and are currently striving towards recovery. One year after the event, the artisanal fisheries fleet has returned to operating almost on a normal scale, while the aquaculture sector is still drastically impacted, with many people continuing to work in different economic sectors and even in other regions of the country. Recovery of the social-ecological system of Sechura likely depends on the occurrence of scallop seed and the financial capacity of small-scale producers to reinitiate scallop cultures. Long-term consequences of this coastal El Niño are yet to be studied, though the need to develop trans-local and trans-sectoral management strategies for coping with disturbance events of this scale is emphasized.

Germination Biology of Sesbania (Sesbania cannabina): An Emerging Weed in the Australian Cotton Agro-environment

Weed Science ◽  
2018 ◽  
Vol 67 (1) ◽  
pp. 68-76 ◽  
Author(s):  
Nadeem Iqbal ◽  
Sudheesh Manalil ◽  
Bhagirath S. Chauhan ◽  
Steve W. Adkins
Keyword(s):  
Seed Germination ◽  
Management Strategies ◽  
Moisture Stress ◽  
Integrated Weed Management ◽  
Burial Depth ◽  
Weed Species ◽  
Physical Dormancy ◽  
Sesbania Cannabina ◽  
Wide Range ◽  
The Impact

AbstractSesbania [Sesbania cannabina(Retz.) Pers.] is a problematic emerging weed species in Australian cotton-farming systems. However, globally, no information is available regarding its seed germination biology, and better understanding will help in devising superior management strategies to prevent further infestations. Laboratory and glasshouse studies were conducted to evaluate the impact of various environmental factors such as light, temperature, salt, osmotic and pH stress, and burial depth on germination and emergence of two Australian biotypes ofS. cannabina. Freshly harvested seeds of both biotypes possessed physical dormancy. A boiling-water scarification treatment (100±2 C) of 5-min duration was the optimum treatment to overcome this dormancy. Once dormancy was broken, the Dalby biotype exhibited a greater germination (93%) compared with the St George biotype (87%). The nondormant seeds of both biotypes showed a neutral photoblastic response to light and dark conditions, with germination marginally improved (6%) under illumination. Maximum germination of both biotypes occurred under an alternating temperature regime of 30/20 and 35/25 C and under constant temperatures of 32 or 35 C, with no germination at 8 or 11 C. Seed germination of both biotypes decreased linearly from 87% to 14% with an increase in moisture stress from 0.0 to −0.8 MPa, with no germination possible at −1.0 MPa. There was a gradual decline in germination for both biotypes when imbibed in a range of salt solutions of 25 to 250 mM, with a 50% reduction in germination occurring at 150 mM. Both biotypes germinated well under a wide range of pH values (4.0 to 10.0), with maximum germination (94%) at pH 9.0. The greatest emergence rate of the Dalby (87%) and St George (78%) biotypes was recorded at a burial depth of 1.0 cm, with no emergence at 16.0 cm. Deep tillage seems to be the best management strategy to stopS. cannabina’s emergence and further infestation of cotton (Gossypium hirsutumL.) fields. The findings of this study will be helpful to cotton agronomists in devising effective, sustainable, and efficient integrated weed management strategies for the control ofS. cannabinain cotton cropping lands.

scholarly journals Numerical Model for the Analysis of Thermal Transients in District Heating Networks

2020 ◽  
Vol 197 ◽  
pp. 01004
Author(s):  
Martina Capone ◽  
Elisa Guelpa ◽  
Vittorio Verda
Keyword(s):  
Carbon Dioxide Emissions ◽  
Renewable Energy Sources ◽  
Management Strategies ◽  
District Heating ◽  
Equivalent Model ◽  
Computational Time ◽  
Physical Parameters ◽  
Thermal Transients ◽  
Proposed Model ◽  
Wide Range

As District Heating (DH) networks are experiencing an evolution towards the so-called 4th generation, there is a need to update the currently used models to take into account the ever-increasing complexity of this technology. Indeed, to further improve the reduction in energy consumption and carbon-dioxide emissions, a wide range of technologies and management strategies are being introduced within district heating, such as a large exploitation of Renewable Energy Sources (RES). As a consequence, thermal transients assume a major importance, posing the need to redefine the relevant physical parameters and to develop a model which accurately describes their behaviour. In this framework, this paper proposes a quantitative analysis of the influence of the pipe heat-capacity on the model. Moreover, an equivalent-model, which is able to take into account the two heat capacities of steel and water in just one equation, is proposed and compared with two commonly used approaches. One of the features of the proposed model is the suitability for application to large networks. To prove its capabilities, an application to the Turin district heating network, which is among the largest systems in Europe, is proposed. Results show significant improvements in terms of accuracy over computational time ratio.

Sign in / Sign up

Export Citation Format

Share Document