Calorific value fuel oils

The cyclone combustion chamber. Here the air is injected tangentially into a usually cylindrical chamber and exhausts through a centrally located exit hole at one end. The cyclone combustors are usually used to bum eflBciently diflBcult-buming materials such as high-ash-content and brown coals, anthracite, high-sulFur-content oils, damp vegetable refuse, poor-quahty-low-calorific-value fuels, etc. 

On a uniform calorific value basis, coal constitutes 69% of the total estimated recoverable resources of fossil fuel in the United States. Petroleum and natural gas are about 7% and oil in oil shale, which is not as of this writing used as a fuel, is about 23%. The 1989 total recoverable reserves of coal are about 500 times the 1989 aimual production (2), whereas the reserves of oil and gas are smaller, the production and consumption rate of oil and gas in the United States is three times that of coal. 

Condensing boilers are now available for both gas- and oil-fired plant, the advantage of these being that the flue gases are further cooled down to below 100°C so that the latent heat available in the flue gas water vapor is recovered. The condensate has to be removed and the boiler capital cost is higher than for conventional plant. However, the boiler plant efficiency is increased to the order of 90 per cent, based upon the fuel gross calorific value. Where the flue gas exit temperatures are in excess of 200° C a further economy can be obtained by the provision of a spray recuperator in the case of gas and flue gas economizers for oil and coal. 

The kerogen content of different oil shales, i.e., the average yield of oil of an oil shale can vary greatly. Most oil shales have oil yields between 50 and 150 1 oil/t oil shale, rich shales may even yield more than 200 1/t. A particular characteristic of oil shale is its high areal density, which can exceed 1 million b/acre at its thickest (Bunger et al., 2004). Oil shale can also be used directly as fuel for electricity generation, as, for instance, in Estonia. However, oil shale is characterised by a low calorific value between 7.5 and 9 MJ/kg (based on LHV), which is about one fifth of the energy content of crude oil (Porath, 1999). 

Dice, M. J. "Approximate Calorific Value of California Fuel Oil," Chem. Metal Eng. 1926, 8, 499. 

These oils are in general triglycerides of fatty acids with 10-24 carbon atoms. The carbon atoms and may be saturated or unsaturated. In addition, they may contain phosphoglycerides. Their calorific value is comparable to conventional fuels. However, they are considered to be less harmful to the environment. 

The analysis of oils for their fuel properties involves a range of standard ASTM tests. For example, flash point is determined by ASTM D93, calorific value by ASTM 129-64,... 

Pyrolysis can be performed for many different reactors. The prodnct distribntion varies markedly between the different reactor types and the reaction conditions, snch as temper-atnre, bed materials or catalyst. The aim of the pyrolysis is the redaction of wastes for landfilling and the prodnction of fnels. Especially fuel oil with a high calorific value is an interesting product. Char can be used as a fuel, but is also seen as a precursor for other carboneous materials such as activated carbon. The best way to obtain these products is decarboxylation of the polymer. In this way carbon oxide-rich gas is produced. 

The method of determining heats of combustion has been described above, for carbon. This method, with use of a bomb calorimeter, is the customary basis for determining the value of a fuel, such as coal or oil. A weighed sample of the fuel is placed in the bomb calorimeter, the bomb is filled with oxygen, and the fuel is burned. The fuel value or calorific value of the fuel is considered to be measured by its heat of combustion, and when large amounts of fuel are purchased the price may be determined by the result of tests in a bomb calorimeter. 

Pyrolysis of Pulp and Paper Sludge. The filter cake containing about 80% moisture was supplied for the cracking reactor without predrying. Heavy oil was fed to the incinerator as the auxiliary fuel. This is different from the case of municipal refuse, but the combustible gas composition and calorific value, flue gas composition and ash were similar to that of municipal refuse. The chemical analysis of combustible gas and flue gas are shown in Tables IX and X. 

Gas. Gas has a high calorific value of more than 1+2,000 KJ/ NM. It is used as fuel for heating the pyrolysis kiln along with the recovered light oil. 

Fuel oil Grade. viscosity. Gross calorific value.BTU/lb. 

The heat of combustion (ASTM D-240, ASTM D-1405, ASTM D-2382, ASTM D-2890, ASTM D-3338, ASTM D-4529, ASTM D-4809, ASTM D-6446, IP 12) is a direct measure of fuel energy content and is determined as the quantity of heat liberated by the combustion of a unit quantity of fuel with oxygen in a standard bomb calorimeter. A high calorific value is obviously desirable in oil used for heating purposes. Calorific value does not, however, vary greatly in the range of paraffinic-type kerosene (ASTM D-240, IP 12). 

The calorific value (heat of combustion) of residual fuel oil (ASTM D-240, IP 12) is lower than that of lower-boiUng fuel oil (and other liquid fuels) because of the lower atomic hydrogen-to-carbon ratio and the incidence of greater amounts of less combustible material, such as water and sediment, and generally higher levels of sulfur. 

For most residual fuel oils, the range of calorific value is relatively narrow and limits are not usually included in the specifications. When precise determinations are not essential, values of sufficient accuracy may be derived... 

Density or specific gravity (relative density) is used whenever conversions must be made between mass (weight) and volume measurements. This property is often used in combination with other test results to predict oil quality, and several methods are available for measurement of density (or specific gravity). However, the density (specific gravity) (ASTM D-1298, IP 160) is probably of least importance in determining fuel oil performance but it is used in product control, in weight-volume relationships, and in the calculation of calorific value (heating value). 

In the early experiments that were made with water-gas mixtures in attempts to synthesize valuable organic liquids, methane apparently was the only product obtained until the effect of pressure was understood, after which the progress toward methanol synthesis was rapid. Aside from the work that had to do quite largely with the production of methane for the enrichment of water-gas or other low calorific value gaseous mixtures in countries without cheap oil, considerable attention has been paid to a study of the effects of various catalysts on the synthesis from the viewpoint of perfecting the methanol and higher alcohol syntheses. Processes have, at the same time, been proposed for the synthesis of liquid fuels from water-gas mixtures in an attempt to produce motor fuels from cheap coal. 

Asphaltenes are derived from the root word "asphalt", a "sticky tar-like substance found naturally in petroleum crude oil." Asphaltenes are complex, high molecular weight aromatic compounds suspended within the fuel. They have high melting points and high carbon/hydrogen ratios with low calorific values. 

From an economic point of view, used plastic can be considered as both an important source of valuable chemicals, mainly hydrocarbons, and an energy source. The calorific value of most plastics is similar to that of fuel oils and higher than that of coals. Plastic wastes can therefore be viewed as potential fuels, when other alternatives of valorization are not possible.9... 

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