Dimitrios Karonis

Study of using JP-8 aviation fuel and biodiesel in CI engines

Abstract The first jet fuels were aviation gasoline (avgas), and the characteristics of subsequent jet fuels have evolved from this original choice, the available supply infrastructure, and the refiners’ capabilities. Earlier on, it was evident that avgas would have to be altered to operate satisfactorily in jet powered aircraft. The present contribution outlines the various requirements that led to development of various operational jet fuels, including United States Jet A (European Jet A-1), JP-4 (NATO code, F-40), JP-5 (NATO code, F-44), JP-7 (US only), JP-8 (F-34), JP-TS (US only), and JP-8+100. To reduce this fuel logistic burden, the NATO Armed Forces are advancing the use of a single fuel for both aircraft and ground equipment. To this end, F-34 is replacing distillate Diesel fuel in many applications. In order to make this type of fuel compatible with direct injection compression engines, the Fuels and Lubricants Laboratory of the National Technical University of Athens, used a stationary Diesel engine fueled with fuel blends containing two different types of biodiesel, at proportions up to 50%. In this paper, fuel consumption and exhaust emission measurements from a single cylinder, stationary, Diesel engine are described. The two types of biodiesel appeared to have equal performance, and irrespective of the raw material used for their production, their addition to the JP-8 aviation fuel improved the particulate matter emissions.

Biodiesel Emissions from a Diesel Vehicle Operated on a Non-legislative Driving Cycle

Abstract The aim of this work was to evaluate the exhaust emissions from a diesel vehicle fueled with diesel/biodiesel blends running in a specific driving cycle. Methyl ester obtained from used frying oil was used as the blending feedstock into the reference diesel fuel to create blends at proportions of 5, 10, 15, and 20% by volume. The on-board emission measurements showed that the addition of biodiesel into the reference diesel fuel demonstrated an increase in NOx emissions. Emissions of CO and hydrocarbons were decreased with the addition of biodiesel; however, this reduction was not significant. Particulate matter emissions followed a decline trend as the addition of methyl ester increased into the baseline diesel fuel. Fuel consumption invariably increased for the biodiesel blends, when the motor vehicle operated under the specific real-world driving cycle.

Use of JP-8 aviation fuel and biodiesel on a diesel engine

The present paper aims to discuss the quality characteristics of Jet Fuels used in the Greek market in comparison with fuels used in other countries and to evaluate jet fuels along with diesel and biodiesel on a diesel engine. To establish the quality characteristics for Jet Fuels of the Greek market, fuel samples were collected from the local refineries on a regular basis, thus monitoring the fuel quality fluctuation over time. JP8, along with diesel and biodiesel, were used alone and in mixtures on a single cylinder stationary diesel engine. Emissions and volumetric fuel consumption were measured under various loads.

The impact of using biodiesel/marine gas oil blends on exhaust emissions from a stationary diesel engine.

The purpose of this work was to investigate the impact of marine gas oil (MGO)/biodiesel blends on the exhaust emissions and fuel consumption in a single cylinder, stationary, diesel engine. Three different origins of biodiesel were used as the blending feedstock with the reference MGO, at proportions of 5 and 10% by volume. Methyl esters were examined according to the automotive FAME standard EN 14214. The baseline MGO and biodiesel blends were examined according to ISO 8217:2005 specifications for the DMA category. Independently of the biodiesel used, a decrease of PM, HC, CO and CO2 emissions was observed. Emissions of NOx were also lower with respect to MGO. This reduction in NOx may be attributed to some physicochemical properties of the fuels applied, such as the higher cetane number and the lower volatility of methyl esters. Reductions in PM for biodiesel blends were lower in the exhaust than those of the reference fuel which was attributed to the oxygen content and the near absence of sulphur and aromatics compounds in biodiesel. However, a slight increase in fuel consumption was observed for the biodiesel blends that may be tolerated due to the exhaust emissions benefits. Brake thermal efficiency was also determined. Unregulated emissions were characterized by determining the soluble organic fraction content of the particulate matter.

USE OF ALTERNATIVE FUELS ON A DIESEL ENGINE

The Single Fuel Concept refers to the NATO initiative towards the use of a single fuel for all land based military aircraft, vehicles and equipment when employed on the European battlefield. The single fuel selected was F-34 (JP-8), which is based upon the civil jet fuel F-35 (Jet A-1), with the inclusion of a military additive possessing anti-icing properties. However, environmental pollution problems were identified in the process of implementing the SFC. The necessity to cope with these and the strict requirements of modern Diesel engines lead to the need to improve the SFC quality. The development of biomass derived substitutes for Diesel fuel is a possible attractive outlet, as it could help improve the quality. The present paper aims to contribute to the evaluation of biodiesel and other types of fuels as possible substitutes of diesel. The fuels used were a typical Greek automotive diesel (EN-590), an ultra low sulfur diesel, a high cetane number diesel fuel, JP-8 and two types of biodiesel, alone or in mixtures with the above fuels. The fuels and the mixtures were analysed for their physicochemical properties in the Laboratory of Fuels Technology and Lubricants of NTUA and the engine tests were conducted on a single cylinder stationary diesel engine.

Impact of Biodiesel Addition on Distillation Characteristics and Cetane Index of Diesel Fuels

AbstractThis paper examines the impact of biodiesel addition on density, viscosity, distillation profile, and cetane index of diesel fuels. Biodiesel has become an important component in the European diesel fuel market. Its addition to diesel alters the distillation profile, which in turn may impact on the cetane index; the latter remains an important parameter for the evaluation of ignition quality of diesel fuels, in combination with the cetane number. In this series of experiments, fifty diesel fuel samples were used (35 automotive diesel samples and 15 heating gasoil samples) as base fuels, to which sunflower oil biodiesel was added at a concentration of 5% volume in the fuel blend. The distillation profile, density, and kinematic viscosity were measured in all base fuels and blends, whereas the cetane indices were calculated from density and distillation measurements. As expected, the results showed increased density and kinematic viscosity due to the biodiesel addition, whereas the front end volatil...

Vapor Pressure and Octane Numbers of Ternary Gasoline–Ethanol–ETBE Blends

The objective of this study was to examine key gasoline properties, such as octane rating and volatility of ternary blends with ethanol and ethyl-tert-butyl-ether (ETBE). Ethanol and ETBE were added in various concentrations in specific refinery gasoline pool components, so a total of 30 gasoline-ethanol-ETBE samples were prepared and tested. Vapor pressure and octane numbers [research octane number (RON) and motor octane number (MON)] were determined for the mixtures containing 0.9-5.5% v/v ethanol and 2.0-9.8% v/v ETBE. Ethanol was always considered a valuable component for refinery gasoline pool due to its good antiknock characteristics. However, its azeotropic behavior in gasoline is considered as a drawback for the vapor pressure of the blend. On the other hand, the use of ETBE in gasoline increases the octane number and lowers the vapor pressure, thus allowing refinery blenders to use a higher vapor pressure base gasoline in the final fuel formulation. Experimental results indicated that ethanol concentration up to 5% v/v in the gasoline formulation increased the vapor pressure of the mixture. The addition of both ethanol and ETBE in the base gasoline resulted in ternary mixtures which smoothed the behavior of the vapor pressure while they acted as excellent octane improvers.

Synthesis of biodiesel from tobacco and waste frying oil using heterogeneous KHCO3/Al2O3 catalyst.

The transesterification of tobacco seed oil and used frying oil to methyl esters (biodiesel) was studied using potassium bicarbonate loaded on alumina as heterogeneous catalyst. Reaction parameters such as catalyst concentration, methanol to oil ratio, reaction time, and agitation speed on the conversion of tobacco seed and used frying oil were investigated. The catalyst loaded KHCO3 of 30 % m/m on Al2O3, after being calcined at 700°C for 6 h, was found to be the optimum catalyst. The quality of the methyl esters was tested according to the European standard EN 14214. The two types of biodiesel produced seemed to meet all the parameters of the European standard except the oxidation stability. In the case of used frying oil biodiesel, not only the oxidation stability was not met, but this biodiesel did not also meet the acid value and water content specifications.

Use of Ethanol along with Biodiesel in Diesel and Jet Fuels on a Stationary Diesel Engine

ABSTRACT The present paper is an effort to evaluate ethanol in diesel fuel and its main alternatives. The fuels used were an ultra low sulfur diesel fuel containing 15% by volume gas-to-liquid (GTL), JP-5 and JP-8 fuels produced in Greece and biodiesel produced from animal fats. The fuels were tested for compliance to the respective specifications at the Fuels Laboratory of the National Technical University of Athens (NTUA). The test fuel matrix consisted of blends of 5-15 % by volume ethanol with diesel, JP-5, JP-8 and with mixtures of the above with 5% by volume biodiesel. The test fuels were used in a stationary single-cylinder diesel engine with indirect injection, in order to evaluate their performance and emissions under various loads. INTRODUCTION The environmental regulations for exhaust emissions from diesel engines have become very stringent in the European Union [1], as well as in the United States and require cleaner fuels in order to be met. In addition, the continuous increase in automotive diesel fuels consumption has raised the need for new alternatives of diesel fuel, derived from domestic and renewable sources. In the military section, there is also the need for use of JP-8 and JP-5 fuels in diesel engines. DIESEL-ETHANOL BLENDS Research on the use of ethanol in diesel fuel was triggered by the global fuel crisis in the 1970’s. [2] Initial investigations were carried out in South Africa and continued in Germany and the United States during the 1980’s. [3] Most of the researchers report significant reduction in particulate matter emissions [4-6]. This point alone justifies the incorporation of ethanol into diesel. Diesel-Ethanol blends, also known as e-diesel

Exhaust Emissions and Physicochemical Properties of Hydrotreated Used Cooking Oils in Blends with Diesel Fuel

Hydroprocessing of liquid biomass is a promising technology for the production of “second generation” renewable fuels to be used in transportation. Its products, normal paraffins, can be further hydrotreated for isomerization in order to improve their cold flow properties. The final product, usually referred to as “paraffinic diesel,” is a high cetane number, clean burning biofuel which is rapidly gaining popularity among researchers and the industry. Nevertheless, the costly isomerization step can be omitted if normal paraffins are to be directly mixed with conventional diesel in low concentrations. In this work, nonisomerized paraffinic diesel produced through hydrotreating of used cooking oil (hydrotreated used cooking oil (HUCO)) has been used in 4 blends (up to 40% v/v) with conventional diesel fuel. The blends’ properties have been assessed comparatively to European EN 590 and EN 15940 standards (concerning conventional automotive diesel fuels and paraffinic diesel fuels from synthesis or hydrotreatment, resp.). Furthermore, the HUCO blends have been used in a standard stationary diesel engine-generator set. The blends have been considered as “drop-in replacements” for standard diesel fuel. As such, no engine modifications took place whatsoever. The engine performance and exhaust emissions of steady-state operation have been examined in comparison with engine operation with the baseline conventional diesel fuel.