91 research outputs found
The role and place of ECEC in integrated working benenfitting vulnerable groups such as Roma
The main purpose of this report is to examine the added value provided by, and the prerequisites for, integrated working ā as well as the crucial role played by ECEC services ā in order to better serve all families, but especially vulnerable and disadvantaged children and families. Separate attention is devoted to Roma children and their families as one of the most vulnerable groups in Europe, often trapped in a vicious circle of poverty, exclusion and discriminatio
Minimal Medium for Optimal Growth and Lipid Production of the Microalgae Scenedesmus dimorphus
The culture of Scenedesmus dimorphus at the laboratory scale has often been in standard microalgae media, such as 3N-Basal Bold medium (3N-BB), which contains 15 different chemicals. Given the extremely tight profit margins of large-scale production of biofuel from microalgae, it is important to identify the minimally sufficient quantities of nutrients necessary to maximize lipid productivity. The individual and interactive effects of six groupings of the components of 3N-BB medium on growth rate, lipid content, and total biomass yield of S. dimorphus were determined. Trace metal and vitamin concentrations were reduced to 1/6 the level of 3N-BB medium without adversely affecting growth rates and biomass concentration, while concentrations of CaCl2 and K2HPO4/KH2PO4 were reduced to 1/10 that of 3N-BB without adversely affecting biomass and lipid concentrations. Both lipid productivity and lipid content were maximized at the lowest NaNO3 concentration (1/10 that in 3N-BB) and independent of MgSO4 concentration, while the interaction of these two chemicals enhanced biomass concentration. (c) 2013 American Institute of Chemical Engineers Environ Prog, 32: 937-945, 201
Characteristics of LPG-diesel dual fuelled engine operated with rapeseed methyl ester and gas-to-liquid diesel fuels
AbstractA Liquefied Petroleum Gas (LPG)-diesel dual fuelled combustion experimental study was carried out to understand the impact of the properties of the direct injection diesel fuels, such as rapeseed methyl ester (RME) and gas-to-liquid (GTL), on combustion characteristics, engine performance and emissions. The experimental results showed that up to 60% of liquid fuel replacement by LPG was reached while keeping engine combustion variability within the acceptable range and obtaining clear benefits in the soot-NOx trade-off. However, the amount of LPG was limited by adverse effects in engine thermal efficiency, HC and CO emissions. LPGāRME showed a good alternative to LPG-diesel dual fuelling, as better engine combustion variability, HC, CO and soot behaviour was obtained when compared to the other liquid fuels, mainly due to its fuel oxygen content. On the other hand, NOx emissions were the highest, but these can be balanced by the application of EGR. LPGāGTL dual fuelling resulted in the highest NOx emissionsĀ benefit over a wide range of engine operating conditions. The high cetane number and the absence of aromatic of GTL are the main parameters for the more favourable soot-NOx trade-off compared to LPGāULSD (ultra low sulphur diesel) dual fuelling
An overview of the utilisation of microalgae biomass derived from nutrient recycling of wet market wastewater and slaughterhouse wastewater
Microalgae have high nutritional values for aquatic organisms compared to ļ¬sh meal, because microalgae cells are rich in proteins, lipids, and carbohydrates. However, the high cost for the commercial production of microalgae biomass using fresh water or artiļ¬cial media limits its use as ļ¬sh feed. Few studies have investigated the potential of wet market wastewater and slaughterhouse wastewater for the production of microalgae biomass. Hence, this study aims to highlight the potential of these types of wastewater as an alternative superior medium for microalgae biomass as they contain high levels of nutrients required for microalgae growth. This paper focuses on the beneļ¬ts of microalgae biomass produced during the phycore-mediation of wet market wastewater and slaughterhouse wastewater as ļ¬sh feed. The extraction techniques for lipids and proteins as well as the studies conducted on the use of microalgae biomass as ļ¬sh feed were reviewed. The results showed that microalgae biomass can be used as ļ¬sh feed due to feed utilisation efļ¬ciency, physiological activity, increased resistance for several diseases, improved stress response, and improved protein retention
Advances in Catalytic Technologies for Biodiesel Fuel Synthesis
The greenhouse effect and its consequences are a growing concern for humanity [...
Noncatalytic Biodiesel Synthesis under Supercritical Conditions
The constant increase in greenhouse gases in the environment is forcing people to look for different ways to reduce such pollution. One of these ways is the use of biodiesel for road transport. Conventional biodiesel production involves the catalytic triglyceride transesterification process. When using homogeneous two-stage catalysis, it is difficult to purify the resulting product from the by-products formed, and the catalysts cannot be reused. In the case of heterogeneous catalysis, the process costs are increased due to separation and regeneration of the catalysts. To solve these problems of catalytic synthesis, a noncatalytic process has been recently studied that which takes place under supercritical conditions for an alcohol or other acyl receptor. In such biodiesel production, fatty feedstocks and alcohols are used as raw materials, with the synthesis taking place at supercritical conditions for alcohol, i.e., high temperature and pressure, thus making the process quite simple. This paper reviews the results obtained from biodiesel synthesis using a noncatalytic supercritical process for transesterification using both alcohols and carboxylate esters of low molecular weight, evaluating the optimal conditions for these processes and biofuel stability at high temperatures
Synthesis of Biodiesel by Interesterification of Triglycerides with Methyl Formate
In the conventional synthesis of biodiesel, not only fatty acid esters (biodiesel) are formed, but also the by-product is the glycerol phase, which amounts to about 10 wt.%. Recently, the studies on the interesterification of oil using carboxylate esters have been launched. In this case, no glycerol is formed, and esters of glycerol and short-chain organic acids soluble in biodiesel are produced. The biodiesel yield is increased, and the biodiesel production process is more economically viable. The process of interesterification with methyl formate yields a mixture of biodiesel and triformylglycerol, which is not inferior in quality to biodiesel, but also has better low-temperature properties. The paper analyzes the application of chemical and enzymatic catalysis methods for the interesterification of triglycerides with methyl formate. The influence of catalyst amount, reagent molar ratio, temperature, and process time on the product yield is presented. The quality indicators of the obtained fuel and their compliance with the requirements of the biodiesel fuel standard are discussed
Application of Microalgae Biomass for Biodiesel Fuel Production
Recently, there has been a growing interest in the use of new types of cheaper raw materials for biodiesel production. There are many prospects for microalgae, which do not compete for land with conventional biodiesel raw materials, are characterized by rapid reproduction and high biomass accumulation, and under certain conditions, some are able to accumulate a large amount of oil. A number of studies have been conducted on the extraction of oil from microalgae cells and transesterification with various acyl receptors. This paper provides an overview of the results of research on microalgal biomass preparation and oil extraction. Indicators of the quality of the oil are presented and its suitability for biodiesel synthesis is analyzed. The homogeneous and heterogeneous catalysts used for oil transesterification are described and the optimal conditions of the process when using various alcohols as acyl receptors are presented. Much attention is paid to the parameters affecting the transesterification efficiency and biodiesel yield. The physical and chemical, and operational and environmental properties of biodiesel obtained from algae oil are analyzed. The evaluation of the economic efficiency of biodiesel synthesis is also presented
GREEN ENERGY FROM MICROALGAE: USAGE OF ALGAE BIOMASS FOR ANAEROBIC DIGESTION
The microalgae biomass can be used for various types of biofuels, including biodiesel and biogas. The aim of this study is to investigate the possibilities of microalgae Scenedesmus sp. and Chlorella sp. (widespread in freshwater Lithuanian lakes) usage for biogas production. Microalgae were cultivated under mixotrophic conditions (growth medium BG11containing technical glycerol). In order to determine biogas yield and quality dependence on feedstock preparation, the analyses of biogas production have been performed with algae biomass prepared in different ways: wet centrifuged; wet centrifuged, frozen and defrost; dry not de-oiled and dry de-oiled. The highest biogas yield in both cases (Scenedesmus sp. ā 646 ml/gDM and Chlorella sp. ā 652 ml/gDM) was obtained from centrifuged, frozen and defrost biomass. Biogas yield was app. 1.46 times higher comparing to yield of biogas produced from wastewater sludge. Our results showed that different types of biomass preparation have no significant influence on quality of biogas
Synthesis of Biodiesel by Interesterification of Triglycerides with Methyl Formate
In the conventional synthesis of biodiesel, not only fatty acid esters (biodiesel) are formed, but also the by-product is the glycerol phase, which amounts to about 10 wt.%. Recently, the studies on the interesterification of oil using carboxylate esters have been launched. In this case, no glycerol is formed, and esters of glycerol and short-chain organic acids soluble in biodiesel are produced. The biodiesel yield is increased, and the biodiesel production process is more economically viable. The process of interesterification with methyl formate yields a mixture of biodiesel and triformylglycerol, which is not inferior in quality to biodiesel, but also has better low-temperature properties. The paper analyzes the application of chemical and enzymatic catalysis methods for the interesterification of triglycerides with methyl formate. The influence of catalyst amount, reagent molar ratio, temperature, and process time on the product yield is presented. The quality indicators of the obtained fuel and their compliance with the requirements of the biodiesel fuel standard are discussed
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