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Mit gleichem kommunalem Mehrzweck-Fahrzeug (Abb. 1) wurden mehrere Fahrzyklen mit konventionellem Dieselantrieb und mit parallelem diesel-elektrischem Hybridantrieb simuliert. Aus den Ergebnissen der realen Fahrzyklen mit konventionellem Dieselmotorantrieb ließen sich die Kraftstoffeinsparpotenziale mit dem Hybridmotor und den verschiedenen Maßnahmen wie Start-Stopp, Rekuperation und Boost ermitteln. Selbst bei diesem Kommunalfahrzeug lassen sich Kraftstoffeinsparungen bis über 20 % nachweisen, obwohl die Fahrzyklen für Hybridanwendungen nicht besonders attraktiv sind. Deutlich höhere Potenziale liegen beispielsweise bei Gabelstaplern und Baumaschinen vor.
Non-esterified plant oils gain ecological and economical importance, particularly in the EU where it is intended to increase the share of renewable energies. Plant oils do not require any chemical treatment so do not cause secondary pollution. The importance of plant oil will increase in Germany for mobile and stationary applications. The generation co-generation of heat and power is subsidized by the German “Erneuerbares Energiegesetz” and the “Kraft-Wärme-Kopplungsgesetz” when renewable fuels are used such as plant oils..
Plant oils have a much higher viscosity than conventional gas oil. It is mandatory to decrease the oil viscosity by heating prior to injection to assure proper injection and to avoid engine damage due to coke formation in the combustion chamber and at the injection nozzle. The German quality standard of Weihenstephan (RK-Qualitätsstandard 05/2000) for rape seed oil should be followed for use as diesel fuel. The chemical composition of plant oils is appreciably different in comparison to diesel fuels derived from mineral oils suggesting also different emission behavior.
Particle and Gaseous Emissions of Diesel Engines Fuelled by Different Non-Esterified Plant Oils
(2007)
The particulate matter and gas emissions of several plant oils are analyzed in the hot exhaust gas under various engine conditions at different speeds and loads The measurement data are compared to the emission values of conventional diesel fuel (gas oil). The investigation concentrates on a modern common rail TDI light duty diesel, four cylinders, for passenger cars. The differences in the gas and particulate matter emission - compared to conventional diesel fuel - are remarkably low for the diesel engine which is properly adjusted for the plant oils. Emission data of an old heavy duty diesel engine are also shown for comparison reasons and reveals large differences. Differences are found in the pressures of the indicator diagram, time resolved over the crank angle. Plant oils consistently exhibit a higher cylinder pressure. The TEM investigation confirms the differences found by the LPME (long path multi-wavelength extinction) on-line analysis.
Plant oils may be used as a sustainable, nearly CO2neutral fuel for diesel engines. This work investigates experimentally the particulate and gaseous emissions of diesel engines fuelled with different non-esterified, pure plant oils. The data are collected from three engines: a) Common rail 1.7 liter passenger car engine from Opel AG b) 12.8 liter truck engine from VOLVO c) Truck engine from MAN AG.
The emissions of the MAN engine have been used to perform AMES tests to analyze possible health impacts of plant oil operation. Finally, all emission results with plant oils have been compared to traditional gas oils.
Non-Esterified Plant Oils as Fuel -Engine Characteristics, Emissions and Mutagenic effects of PM-
(2009)
Plant oils may be used as a sustainable, nearly CO2 neutral fuel for diesel engines. This work investigates experimentally the particulate and gaseous emissions of diesel engines fuelled with non-esterified, pure plant oils with the quality standard of DIN V 51605 (Weihen-stephan RK-Qualitätsstandard 05/2000). The data are collected from three engines:
Common rail passenger car engine from OPEL AG
Truck engine from VOLVO
Truck engine from MAN AG
All engines have been correctly adjusted to plant oil operation.
The OPEL and VOLVO engines served for the basic investigations. The emissions of the MAN engine have been used to perform AMES tests to analyze possible health impacts of plant oil operation.
The experimental data show a reduction of particulate matter compared to traditional gasoil which may yield up to 50 % for. The particulate matter shows same primary particle sizes but the agglomerates as collected on TEM grids are different - the plant oil soot particles tend to form larger aggregates [4]. The gaseous emissions of CO and hydrocarbons HC are generally lower compared to the operation with gasoil. However, the NOX emissions are slightly higher. This may be contributed to the measured higher combustion chamber pressures and temperatures when fuelled by plant oils.
Emission samples have been extracted from ESC cycles of 13 step tests to perform the AMES test which give indication on carcinogen substances. The AMES test results gave no indication of mutagenic effects exceeding the detection limits. No significant differences could be found comparing the emissions of plant oil and gasoil operation. Thus, it can be stated that the emission from plant oil operation does not have a health impact different to traditional gas oil. This is in contrast to some other publications — a deeper insight shows that these investigations did not properly modify the engine for plant oils. It is mandatory to make the engine modification to pre-warm the plant oils to approx. 90°C prior to injection. The engine's warm-up phase needs special care to avoid any coking at the injection system and combustion chamber surfaces. The publications where a higher health risk was claimed to be found in the exhaust of plant oil fuels, did not pre-warm the plant oils — cold plant oils have been injected in the combustion chamber instead. This results in incomplete atomization and incomplete combustion with a lot of hazardous emission species (see also [4,11]. Such an operation will damage the engine after relatively short times and is, therefore, not realistic.
The investigated fuels had some influence on the engine characteristics. Higher temperatures and pressures in the cylinder have been detected for some plant oils compared to gasoil. This increase is explained by the higher oxygen content within the plant oils.
Das Wort Geothermie kommt aus dem Griechischen und setzt sich aus „Geo“ = Erde und „Thermie“ = Wärme zusammen. Bei der Geothermie wird die Wärme des warmen Untergrunds genutzt. Geothermie ist eine regenerative (CO2 freie), stetig verfügbar, von Witterungseinflüssen, Tages- und Jahreszeiten unabhängige Energiequelle, was sie von anderen regenerativ/erneuerbaren Energien wie z. B. Wind und Photovoltaik unterscheidet. Tiefengeothermische Kraftwerke sind grundlastfähig und können andere CO2 intensive Grundlastkraftwerke wie Steinkohlekraftwerke ersetzen. Es wird die oberflächennahe (0–400 m) und die tiefe Geothermie (> 400 m) unterschieden. Oberflächennahe Geothermie wird zur Wärmeversorgung von Gebäuden eingesetzt. Tiefe Geothermie kommt zur Strom- und Wärmeerzeugung zum Einsatz.
Specific prototypes of sedimentation field flow fractionation devices (SdFFF) have been developed with relative success for cell sorting. However, no data are available to compare these apparatus with commercial ones. In order to compare with other devices mainly used for non-biological species, biocompatible systems were used for standard particle (latex: 3–10 μm of different size dispersities) separation development. In order to enhance size dependent separations, channels of reduced thickness were used (80 and 100 μm) and channel/carrier-phase equilibration procedures were necessary. For sample injection, the use of inlet tubing linked to the FFF accumulation wall, common for cell sorting, can be extended to latex species when they are eluted in the Steric Hyperlayer elution mode. It avoids any primary relaxation steps (stop flow injection procedure) simplifying series of elution processing. Mixtures composed of four different monodispersed latex beads can be eluted in 6 min with 100 μm channel thickness.
The three wavelength extinction method (3-WEM) was applied for the on-line particle analysisof suspensions of monodisperse latex beads and polydisperse metal oxide particles of industrialinterest. Comparative measurements were performed by photon correlation spectroscopy (PCS). Thedata of latex particles obtained by 3-WEM and PCS are in good agreement with the manufacture’svalues. Also, the values of oxide particles measured by means of the two techniques are in reasonableagreement despite of the irregular particle shape.Discrepancies are observed by comparing the oxideparticle size results with those of scanning electron microscopy, which is due to the broad sampledistributions and shape irregularities.
Soot particles emitted from a light duty (LD) Volkswagen diesel engine running at different operating points (speed and torque levels) are analyzed for mean size determination using a laser‐based three Wavelength Extinction Method (3‐WEM). For this reason, collected soot samples are suspended using an appropriate sample preparation technique with optimized conditions of sonication as it revealed its effect on the soot mean particle size measured by 3‐WEM.
An online Scanning Mobility Particle Analyzer (SMPS) is also used to measure soot emission at identical engine operating points. Size values obtained from SMPS are lower than those of suspended soot samples obtained from 3‐WEM. The size discrepancies are mainly related to the required sample preparation procedure employed for 3‐WEM measurements. The engine operating points affect, differently, the size measurements obtained from SMPS and 3‐WEM.
Sedimentation Field‐Flow Fractionation (SdFFF) is used for density determination of soot samples based on size measurements of fractions collected at peak maxima of fractograms using the off‐line hyphenation with 3‐WEM. It is assumed that a size dependent separation of soot particles occurred with a uniform particle density over the whole size distribution. An average density value is used for the conversion of soot fractograms to size distributions. Discrepancies are also found with size distribution profiles obtained from SMPS for the same engine operating points, due to the sample preparation procedure employed for SdFFF measurements.
Kolbenmotoren finden in der Energieversorgung vielfältig Verwendung als Notstromaggregate, als Antrieb für Pumpen in Großkraftwerken und in dezentralen Blockheizkraftwerken (BHKW). Motoren für Notstromaggregate und zum Antrieb von Arbeitsmaschinen werden meist mit Diesel-Kraftstoff betrieben. In BHKW dominieren Gasmotoren, wobei Erdgas, Bio-, Deponie- oder Klärgas bevorzugt sind. Die wesentliche Thermodynamik der Otto-, Diesel- und Stirling-Motoren wird in Kürze behandelt, während die Gasmotoren tiefere Behandlung finden. Die Motoren für die Energieversorgung stammen i. Allg. von mobilen Anwendungen ab und werden an die energietechnischen Anwendungen angepasst. Technische Details der Motoren sind in der Fachliteratur zu finden, z. B. [1]. Die Website [2] gibt einen umfassenden Überblick über Hersteller und deren Kolbenmotoren.
Kleine Anlagen zur dezentralen Strom- und Waermeerzeugung (Block(heiz)kraftwerke) gewinnen auf Grund ihrer vielfaeltigen Einsatzmoeglichkeiten zunehmend an Bedeutung. Die CO2-Bilanz mit Deponiegas bzw. Erdgas betriebenen Blockkraft- und Block(heiz)kraftwerken wird gegenuebergestellt. Es zeigt sich, dass durch den Einsatz von Deponie-Blockkraftwerken bzw. von Blockheizkraftwerken CO2-Einsparungen von ueber 100 kg CO2/MWh im Vergleich zur getrennten Waerme- und Stromerzeugung erzielt werden koennen.
Zur Messung geringer Massenkonzentrationen und der Partikelgrößenverteilung unter hohen Druck- und Temperaturbedingungen, wie sie z.B. bei Überwachung des Gasstromes in Druckwirbelschichtfeuerungen oder in Druckkohlestaubfeuerungen vorkommen, wird ein kompensiertes Streulichtfotometer vorgeschlagen. Streulicht- und Transmissionswerte des Partikelkollektivs werden erfasst und miteinander verknüpft. Als Vorteil dieses Mess- und Auswerteprinzips ergibt sich im Gegensatz zu konventionellen Fotometern eine weitgehende Unempfindlichkeit gegenüber Fenster-Verschmutzung und Alterung von Komponenten. Das neue Konzept ist bis etwa 900 ºC einsatzfähig.
A prototype multiwavelength sensor able to characterise soot emissions in Diesel exhaust in terms of size and concentration has been tested against other methods for diesel particle measurements like electrical mobility sizing (SMPS) and raw exhaust gravimetric sampling (RES). Measurements carried out with the prototype sensor were correlated with the SMPS by assuming spherical and/or fractal aggregate morphology of the particles. Correlation of RES gravimetric data against the sensor and the SMPS led to the calculation of the solid density for soot particles to be 2.3 gr/cm3.
Unter fossilen Energieträgern verstehen sich energie- und kohlenstoffhaltige Stoffe, die in mehreren Millionen Jahren aus Biomassen unter dafür günstigen Bedingungen (Sauerstoffausschluss) gebildet wurden. Das geologische Alter von Steinkohle beträgt über 250 Millionen Jahre, das von Braunkohle ca. 50 Millionen. Derzeit werden deutlich mehr fossile Energieträger verbraucht als nachgebildet. Während in Deutschland die Stilllegung von Dampfkraftwerken, die mit Steinkohle befeuert werden, begonnen hat, steigt global der Verbrauch dieser Brennstoffe weiterhin an. Die Steinkohleförderung erreichte im Jahr 2019 weltweit den Wert von 7,3 Milliarden Tonnen, mit einer Steigerung von immerhin fast 3 % gegenüber dem Vorjahr 2018 nach [1]. Dieser Anstieg erfolgte hauptsächlich in China und Indonesien – in Deutschland ging der Kohleverbrauch in diesem Zeitraum zurück.