1,721,583 research outputs found
Analyzing the information basis: characterization and quality evaluation of resouce budget data
No full textIntegrating anthropogenic material stocks and flows into modern resource classification frameworks
No full text
Material flow accounting at plant level case study: heavy metal flows in blast furnace process
No full textImpact of reduced anthropogenic emissions and century flood on the phosphorus stock, concentrations and loads in the Upper Danube
Full text linkAbstractPatterns of changes in the concentration of total and soluble reactive phosphorus (TP, SRP) and suspended sediments at different flow levels from 1991 to 2013 in the Austrian Danube are statistically analyzed and related to point and diffuse emissions, as well as to extreme hydrological events. Annual loads are calculated with three methods and their development in time is examined taking into consideration total emissions and hydrological conditions. The reduction of point discharges achieved during the 1990s was well translated into decreasing TP and SRP baseflow concentrations during the same period, but it did not induce any change in the concentrations at higher flow levels nor in the annual transport of TP loads. A sharp and long-lasting decline in TP concentration, affecting all flow levels, took place after a major flood in 2002. It was still visible during another major flood in 2013, which recorded lower TP concentrations than its predecessor. Such decline could not be linked to changes in point or diffuse emissions. This suggests that, as a result of the flood, the river system experienced a significant depletion of its in-stream phosphorus stock and a reduced mobilization of TP rich sediments afterwards. This hypothesis is corroborated by the decoupling of peak phosphorus loads from peak maximum discharges after 2002. These results are highly relevant for the design of monitoring schemes and for the correct interpretation of water quality data in terms of assessing the performance of environmental management measures
Assessing the environmental impact of fuels: A comparison of greenhouse gas emissions from gasoline and bioethanol made of sugar cane through a life cycle analysis.
Full text linkObwohl die Biokraftstoffe aus erneuerbaren und "saubereren" Quellen herrühren als die aus Erdöl erzeugten Brennstoffe, werden während ihrer gesamten Produktionskette verschiedene andere Energiequellen verwendet - einschließlich derselben fossilen Brennstoffe, welche sie ersetzen sollen. Um die tatsachlichen Vorteile (wenn es denn Vorteile sind) der Biokraftstoffe feststellen zu können, ist es daher erforderlich, ihren gesamten Lebenszyklus zu analysieren und eine sorgfältige Bestandsaufnahme der durch sie in jeder Phase des Lebenszyklus verursachten (direkten und indirekten) Emissionen durchzuführen.In diesem Zusammenhang soll die vorliegende Arbeit zur Bewertung der Verwendung von Bioethanol (hergestellt aus Zuckerrohr) beitragen, in Hinblick auf eine mögliche Substitution von Benzin für Zwecke des Individual-Personenverkehrs. Um die Auswirkungen für die Umwelt zu beurteilen, sollen die jeweils entstehenden Treibhausgas-Emissionen (d.h. die Emissionen der den Treibhauseffekt verursachenden und damit zur Erderwärmung und zum globalen Klimawandel beitragenden Gase) während des gesamten Lebenszyklus beider Kraftstoffe untersucht und einander gegenübergestellt werden.Für den Vergleich beider Kraftstoffe und der Berechnung der durch sie freigesetzten THG-Emissionen wird eine Lebenszyklus-Analyse durchgeführt, die sämtliche von der Herstellung bis zum Verbrauch ablaufenden Prozesse mit einschließt. Dabei wird für jeden Kraftstoff ein jeweils spezifisches Szenario konstruiert, wo dessen Verwendung in österreichischem Territorium zu derzeit herrschenden (und vergleichbaren) Rahmenbedingungen simuliert werden kann. Das erste Szenario konstituiert eine Sequenz hypothetischer Prozesse, welche mit dem Anbau von Zuckerrohr, des Rohstoffs für Bioethanol, und dessen Raffination in Brasilien beginnt und mit dem Konsum des hergestellten Biokraftstoffs in Osterreich (ausgehend von den 24 derzeit existierenden Tankstellen) endet. Das zweite Szenario zur Repräsentation der Emissionen des österreichischen Benzins berücksichtigt alle Prozesse des Lebenszyklus dieses Kraftstoffs - angefangen bei den verschiedenen Rohöllieferanten bis zum durchschnittlichen FFV-Auto, das den Kraftstoff konsumiert.Although biofuels derive from renewable and "cleaner" sources than the fuels produced from petroleum, during their entire production chain various other energy sources are used - including the same fossil fuels, which they are supposed to replace. To assess the actual benefits (if there are benefits) of the use of biofuels, it is therefore necessary to analyze their entire life cycle and to accomplish a careful inventory of the (direct and indirect) emissions caused by them in every phase of the life cycle.In this context, the present study should contribute to evaluate the use of bioethanol (produced from sugar cane), having in view a possible substitution of gasoline for purposes of individual passenger transport.To assess the impact on the environment, the resulting greenhouse gas emissions (i.e., the emissions of gases that cause the greenhouse effect and thus contribute to global warming and climate change) have to be examined throughout the life cycle of both fuels and compared with each other.For the comparison of the two fuels and the calculation of the GHG emissions released by them, a life cycle analysis is performed, which includes all involved processes (from production until consumption). For each fuel a specific scenario is constructed, where its use can be simulated in Austrian territory under similar and currently existing (or probable) conditions. The first scenario constitutes a hypothetical sequence of processes that begins with the cultivation of sugar cane, the raw material for bioethanol, and the refining in Brazil and ends with the consumption of the produced biofuel in Austria (based on the 24 currently existing gas stations). The second scenario should represent the emissions of the Austrian gasoline and takes into account all processes of the life cycle of this fuel - from the various crude oil suppliers to the average FFV-car that consumes the fuel.<br /
Carbon dioxide reduction potential of sugar cane bagasse in Guatemala
Full text linkGuatemala is a country with a large amount of renewable resources the potential for greenhouse gases reduction is promising. At the same time renewable resources have been recently gaining notability as law makers increasingly foster them by providing tax advantages and incentives. In Guatemala, biomass is used in various forms; such is the case of fuel-wood and bagasse. Yet CO2 and other GHGs' emissions continue to be a problem. This work focuses on sugar cane bagasse which is the source of 3% of the final energy consumption and its potential in GHG emission reduction by identifying four possible usages. In the year 2009 Guatemala produced 18 million tonnes of sugar cane. This resulted in an output of 3 million tonnes of bagasse for that year. Out of which, 60% was converted into electricity; the rest was disposed of, sold to cattle ranchers or used as fertilizer. In this work the author tries to identify the advantages or disadvantages of using bagasse in each of the four alternative usages by taking into consideration the available technologies and their potential in reducing greenhouse gas emissions
- …
