Diesel properties

Though FAME has limited oxidation stability, they remain a valid alternative for diesel. Conventional diesel fuel has a boiling range of 180-340 °C, with a composition of n-alkanes, cycloalkanes, alkyl benzenes, and polyaromatic compounds. Fossil diesels have a CN in the range 40-100. FAME has properties that are close to all these basic diesel properties. FAME can also easily blend with fossil diesel at any level due to their similar solvent behavior the viscosity of fossil diesel and biodiesel are also in the same range. 

Table 5.5. Diesel Property Changes between Feed and S-Zorb-Diesel Process Product132...

Table I. GTL Diesel and Base Fuel Diesel Properties...

The main applicatiOTi for plain orifice nozzles is in fuel combustion [1]. Therefore most correlations have been developed for this application [46—51]. Tanasawa and Toyoda [46] derived 24.5.i for diesel sprays in still air. Harmon [47] derived a correlation 24.5.ii that considered many different properties for both the liquid and the gas. In (24.52), liquid viscosity has very little impact on the SMD. Also, it predicts that an increase in surface tensitm will lead to finer atomization. This is contrary to the findings of most other experiments. Figure 24.31 shows a graph with both equations plotted plus (24.5.iii) by Merrington and Richardson [48], where do was set to 0.2 mm and (7l to 50 m/s. The diesel properties were taken from [50] as follows p = 826 kg/m, p = 2.744 mPa s and a = 0.0286 N/m. 

What extent achieving low sulfur speeifications can improve other key diesel properties. 

Table 23.1 Comparative diesel and 10% CPO diesel properties (Ha et al., 2009c)...

All properties required by diesel fuel are justified by the characteristics of the diesel engine cycle, in particular the following ... 

The properties of straight run diesel fuels depend on both nature of the crude oil and selected distillation range. Thus the paraffinic crudes give cuts of satisfactory cetane number but poorer cold characteristics the opposite will be observed with naphthenic or aromatic crudes. The increasing demand for diesel fuel could lead the refiner to increase the distillation end point, but that will result in a deterioration of the cloud point. It is generally accepted that a weight gain in yield of 0.5% could increase the cloud point by 1°C. The compromise between quantity and quality is particularly difficult to reconcile. 

For other physical properties, the specification differences between diesel fuel and home-heating oil are minimal. Note only that there is no minimum distillation end point for heating oil, undoubtedly because tbe problem of particulate emissions is much less critical in domestic burners than in an engine. 

The properties linked to storage and distribution do not directly affect the performance of engines and burners, but they are important in avoiding upstream incidents that could sometimes be very serious. We will examine in turn the problems specific to gasoline, diesel fuel, jet fuel and heavy fuel. 

Properties of cuts Light gasoline Heavy gasoline Kerosene Diesel oil AR VD VR... 

Product properties Light gasoline Heavy gasoline Diesel oil Residue... 

Products excellent properties Kerosene smoke point 25-30 mm Diesel cetane number 55-60 Residue BMCl 15 VI 5= 125 No post-treatment... 

Coley, T.R. (1989), Diesel fuel additives influencing flow and storage properties . In Gasoline and diesel fuel additives (Owen, K. Ed.). John Wiley. 

The products could be classified as a function of various criteria physical properties (in particular, volatility), the way they are created (primary distillation or conversion). Nevertheless, the classification most relevant to this discussion is linked to the end product use LPG, premium gasoline, kerosene and diesel oil, medium and heavy fuels, specialty products like solvents, lubricants, and asphalts. Indeed, the product specifications are generally related to the end use. Traditionally, they have to do with specific properties octane number for premium gasoline, cetane number for diesel oil as well as overall physical properties such as density, distillation curves and viscosity. 

However, this conventional method presents a certain number of limitations. In the first place, the traditional end-use property itself can be difficult to determine. Consider the cetane number for example is it a good characterization of diesel fuel with respect to its behavior in commercial diesel engines In the second place, concern for protecting the environment imposes new specifications which are often specifications linked to the composition of products very low content of certain contaminants, reduced levels of certain families of compounds, or even a specific compound as already discussed. 

Properties Methanol Ethanol Propane Methane Isoctane Unleaded gasoline Diesel fuel 2... 

Foam Control. Whereas some siUcones are known to be foam promoters, Dow Corning FS-1265 Fluid is a Hquid fluorosiUcone with effective antifoam properties. Petroleum industry appHcation of fluids and dispersions in gas—oil separators on offshore drilling platforms has been successful. Their use peaked in the early 1980s, coinciding with constrained cmde oil capacity and production. Diesel fuels are an excellent solvent for dimethyl silicones and render them ineffective as an antifoam. A new antifoam which does not require the use of added siUca is formulated from a fluorosiUcone copolymer. It has shown promise to antifoam (8) diesel fuel (see Defoamers). 

Owing to its properties, methanol is not recommended for aircraft or marine fuel uses. Methanol caimot be used in conventional diesel-powered vehicles without modifications to the fuel system and engine. Simple methanol—diesel blends are not possible because of insolubiUty. Heavy-duty diesel engines have been adapted to use neat methanol by many U.S. manufacturers, and several are being used in field demonstrations (82) (see Alcohol fuels). 

Alternative fuels fall into two general categories. The first class consists of fuels that are made from sources other than cmde oil but that have properties the same as or similar to conventional motor fuels. In this category are fuels made from coal and shale (see Fuels, synthetic). In the second category are fuels that are different from gasoline and diesel fuel and which require redesigned or modified engines. These include methanol (see Alcohol fuels), compressed natural gas (CNG), and Hquefted petroleum gas (LPG). 

Liquid fuels for ground-based gas turbines are best defined today by ASTM Specification D2880. Table 4 Hsts the detailed requirements for five grades which cover the volatility range from naphtha to residual fuel. The grades differ primarily in basic properties related to volatility eg, distillation, flash point, and density of No. 1 GT and No. 2 GT fuels correspond to similar properties of kerosene and diesel fuel respectively. These properties are not limited for No. 0 GT fuel, which allows naphthas and wide-cut distillates. For heavier fuels. No. 3 GT and No. 4 GT, the properties that must be limited are viscosity and trace metals. 

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