Search results for "Biofuel"
showing 10 items of 142 documents
Upgrade of citrus waste as a biofuel via slow pyrolysis
2015
Abstract Slow pyrolysis (200–650 °C) experiments on citrus residues (orange peel waste “OP” and lemon peel waste “LP”) were carried out in lab scale fixed bed batch reactor. Bio-oil and bio-char obtained by thermal degradation are more stable, more homogeneous and higher energy content fuels when compared to the parent feedstock. Thermogravimetric analysis (TGA) showed higher stability of LP waste, which appears related to the higher lignin content . Mass and energy yields of solid and liquid products (i.e., char and oil) were measured to determine the effects of peak temperature on feedstock. A linear correlation between Gross Calorific Value (GCV), peak temperatures and mass loss (ML) all…
Trace compounds affecting biogas energy utilisation – A review
2011
Abstract This paper investigates the trace compounds affecting energy utilisation in biogas that come from different production sites. With biogas being more widely used in different energy applications more interest has arisen for the specific composition of biogas. In traditional energy applications, methane and hydrogen sulphide contents have had the most influence when energy utilisation application has been considered. With more advanced processes also the quantity and quality of trace compounds is more important. In regards to trace compounds, it was found that the concentrations and the variations of volatile organic compounds (VOCs) can be high in different landfills, especially, wi…
Emerging techniques in bioethanol production: from distillation to waste valorization
2019
Ethanol production from biomass, especially waste biomass, and the use of such ethanol as fuel can reduce fossil fuel consumption and ameliorate the hidden costs of burning fossil fuels such as its environmental impact. However, bioethanol production suffers from several limitations such as being energy-intensive and generating a sizeable amount of waste. This review briefly describes the aspects related to bioethanol production and focuses on both theoretical and practical approaches for process improvements. Several green emerging distillation techniques, such as ohmic-assisted hydrodistillation, membrane-assisted distillation, and heat integrated techniques, are shown to be energy-saving…
Measurement methodology for greenhouse gas emissions from storage of forest chips–A review
2015
Abstract Research on greenhouse gas emission related to solid biofuels has focused mainly on the emissions from end use and the production chain. GHG emissions from the storage of forest chips have not received much attention in recent literature. In order for EU emission reduction targets to be fully understood, emissions from solid biofuel storage needs to be better described. Usually emissions from chip piles have been modelled using studies from organic waste composting but these two materials can differ appreciably; for example the C/N-ratio and moisture content. Herein, previous studies on greenhouse gas emissions from forest chips piles during storage are reviewed. The objective is t…
Manure as a potential source of renewable energy: The behaviour and characterisation of biofuels generated from three animal manure types when subjec…
2020
Regions with high livestock density lack sufficient land on which to apply manure without exceeding the legal limits set by the European Union Directives. The lack of manure processing alternatives aggravates the situation, especially in the case of islands. Consequently, manure becomes a liability rather than an asset. Results indicate that pyrolysis is an option for manure processing. However, a significant limitation is the moisture content of the starting material, that could compromise the process efficiency. Yields of biogas, bio-oil and biochar, all of which have a potential use as biofuels, are particular to animal type and manure handling system. The conversion of manure to biofuel…
Determination of organic silicon compounds in biogas from wastewater treatments plants, landfills, and co-digestion plants
2010
Abstract The study determined the organic silicon compounds in biogases from landfills, wastewater treatment plants (WWTPs), and biogas plants processing different organic material. The aim was to provide information for gas utilisation applications, as siloxanes are reported to shorten the life time of engines when biogas is used for energy production. In total, 48 samples were measured. The total concentration of organic silicon compounds in landfill and WWTP gases varied from 77 to 2460 μg/m3 while the concentrations in biogases from biogas plants varied from 24 to 820 μg/m3. The total concentration of organic silicon compounds was lowest (24 μg/m3) in the biogas plant processing grass a…
Torrefied versus conventional pellet production – A comparative study on energy and emission balance based on pilot-plant data and EU sustainability …
2015
Abstract Torrefaction is an emerging technology which enables greater co-firing rates of biomass with coal. To date however there has been a lack of real production data from pilot-scale torrefaction plants. Without such data any environmental benefits of torrefied pellet production are difficult to quantify. In this study data on consumable inputs from a semi-industrial torrefaction plant and the physical properties of produced pellets are used to analyse energy input and air emissions of torrefied pellet production and product transport. EU sustainability criteria are used to compare CO2-equivalent emissions from torrefied and conventional pellet production starting from harvesting of log…
Sustainability of food industry wastes: a microbial approach
2021
Abstract Agro-food industrial by-products signify a grave environmental problem. In addition to the conventional irrigation with wastewaters, the application of solids to the soil, and the extraction of worthwhile compounds for the pharmaceutical, cosmetics, and food industries, a microbiological strategy is also possible. In this review, the most promising microbiological methods for the valorization of wine and oil by-products are shown. Recently, there has been an upsurge in the exploitation of the waste materials generated by the wine and olive oil industries. Treatments by physical and chemical processes are generally costly, and they do not often provide entire solutions. Microbiologi…
Valorization of winery and oil mill wastes by microbial technologies
2015
Agro-food industrial wastes represent a serious environmental problem in producing countries. In addition to the traditional irrigation with wastewaters, application of solids to the land, and the extraction of valuable compounds for the pharmaceutical, cosmetics and food industries, a microbiological approach is also available. In this review, the most promising microbiological processes for the valorization of wine and oil by-products are presented. Recently, there has been an upsurge in the exploitation of the waste materials generated by the wine and olive oil industries. Treatments by physical and chemical methods are generally expensive, and they do not often provide complete solution…
Thermodynamic and Kinetic Modeling of Co-utilization of Glucose and Xylose for 2,3-BDO Production by Zymomonas mobilis
2021
Prior engineering of the ethanologen Zymomonas mobilis has enabled it to metabolize xylose and to produce 2,3-butanediol (2,3-BDO) as a dominant fermentation product. When co-fermenting with xylose, glucose is preferentially utilized, even though xylose metabolism generates ATP more efficiently during 2,3-BDO production on a BDO-mol basis. To gain a deeper understanding of Z. mobilis metabolism, we first estimated the kinetic parameters of the glucose facilitator protein of Z. mobilis by fitting a kinetic uptake model, which shows that the maximum transport capacity of glucose is seven times higher than that of xylose, and glucose is six times more affinitive to the transporter than xylose.…