Burning characteristics

The essential properties of kerosene are flash point (ASTM D-56, ASTM D-93, ASTM D-3828, IP 34, IP 170, IP 303), distillation range (ASTM D86, ASTM D-1160, ASTM D-2887, ASTM D-6352), burning characteristics (ASTM D-187, IP 10), sulfur content (ASTM D-129, ASTM D-2622, ASTM D-3120, ASTM D-3246, ASTM D-4294, ASTM D-5453, ASTM D-5623, IP 61, IP 336, IP 373), color (ASTM D-156, ASTM D-1209, ASTM D-1500, ASTM D-1554, ASTM D-2392, ASTM D-3830, ASTM D-6045), and cloud point (ASTM D-2500, ASTM D-5772, ASTM D-5771, ASTM D-5773, IP 219). In the case of the flash point (ASTM D-56), the minimum flash temperature is generally placed above the prevailing ambient temperature the fire point (ASTM D-92) determines the hre hazard associated with its handling and use. 

Acids can be present in kerosene aviation turbine fuels because of acid treatment during rehning. These trace acid quantities are undesirable because of the possibility of metal corrosion and impairment of the burning characteristics and other properties of the kerosene. The potential for metals in kerosene is less than it is for aviations fuels, but several of the same tests can be applied (Chapter 6). 

One test method (ASTM D-1093) is used solely for the qualitative determination of the acidity of hydrocarbon liquids and their distillation residues. The results are qualitative. Basicity determination can also be performed with a small change in the procedure (see below). In the test method, a sample is shaken with water and the aqueous layer is tested for acidity with methyl orange indicator (red color). Basicity can be determined with phe-nolphthalein indicator (pink color) instead of the methyl orange indicator. 

Another test method (ASTM D-3242, IP 354) covers the determination of the acidity in an aviation turbine fuel in the range 0.000-0.100 mg potassium hydroxide/g, but the test is not suitable for determining signihcant acid contamination. In this test, a sample is dissolved in a solvent mixture (toluene plus isopropyl alcohol and a small amount of water) and under a stream of nitrogen is titrated with standard alcoholic KOH to the color change from orange in acid to green in base via added indicator p-naphtholbenzein solution. 

The ability of kerosene to burn steadily and cleanly over an extended period (ASTM D-187, IP 10) is an important property and gives some indi- 

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When a customer agrees to purchase gas, product quality is specified in terms of the calorific value of the gas, measured by the Wobbe index (calorific value divided by density), the hydrocarbon dew point and the water dew point, and the fraction of other gases such as Nj, COj, HjS. The Wobbe index specification ensures that the gas the customer receives has a predictable calorific value and hence predictable burning characteristics. If the gas becomes lean, less energy is released, and if the gas becomes too rich there is a risk that the gas burners flame out . Water and hydrocarbon dew points (the pressure and temperature at which liquids start to drop out of the gas) are specified to ensure that over the range of temperature and pressure at which the gas is handled by the customer, no liquids will drop out (these could cause possible corrosion and/or hydrate formation). 

Standard Test Methodfor Su face Burning Characteristics ofBuildingMaterials ASTM E84, American Society for Testing and Materials, Philadelphia, Pa., 1975. 

Aromatic and Nonaromatic Hydrocarbon Separation. Aromatics are partially removed from kerosines and jet fuels to improve smoke point and burning characteristics. This removal is commonly accompHshed by hydroprocessing, but can also be achieved by Hquid-Hquid extraction with solvents, such as furfural, or by adsorptive separation. Table 7 shows the results of a simulated moving-bed pilot-plant test using siHca gel adsorbent and feedstock components mainly in the C q—range. The extent of extraction does not vary gready for each of the various species of aromatics present. SiHca gel tends to extract all aromatics from nonaromatics (89). 

Loading density in terms of required burning characteristics... 

Gun Propellents. Although the stresses on individual gun propellant grains are less severe because of the small size, these propellants must withstand much higher weapon pressures and accelerations. Formulation options are usually more limited for gun propellants than for rocket propellants because the products of combustion must not foul or corrode a gun, should have a low flame temperature, and should exhibit minimum flash and smoke characteristics. Gun propellants are examined microscopically for porosity, are tested for mechanical characteristics, and fired in closed bombs to determine the burning characteristics. 

Natural gas is attractive as a fuel ia many appHcatioas because of its relatively clean burning characteristics and low air pollution (qv) potential compared to other fossil fuels. Combustion of natural gas iavolves mixing with air or oxygen and igniting the mixture. The overall combustion process does not iavolve particulate combustion or the vaporization of Hquid droplets. With proper burner design and operation, the combustion of natural gas is essentially complete. No unbumed hydrocarbon or carbon monoxide is present ia the products of combustioa. 

Building code requirements for fire performance are mainly concerned with noncombustibiUty (41), fire endurance (42,43), and surface burning characteristics (44). Wood, even in its treated form, does not meet the building code requirements for a noncombustible material. However, for some specific apphcations where noncombustible materials are required, the codes permit the substitution of fire retardant treated wood. 

The surface burning characteristics (flame spread index and smoke developed index) for wood and wood products as measured by American Society for Testing and Materials (44) can be reduced with fire retardant treatments, either chemical impregnation or coatings (48). Fire retardant treatments also reduce the heat release rate of a burning piece of wood (49,50). The heat release rates (51) of the burning materials are an important factor in fire growth. 

The economic value of natural gas is primarily determined by the thermal energy it contains, which is expressed in British thermal units (Btu) or calorific value (CV). Other important physical properties comprise the liquid content, the burning characteristics, the dew point and the compressibility. In order to enable the calculation of these properties from its composition, a natural gas analysis should contain a detailed determination of all of the individual components, even in the low-concentration range. 

Because of its clean burning characteristics, kerosene commands a higher price than other fuels in its boiling range. 

Fuel gas to fuel gas purging The purge may be carried out by burning the gas under supervision on an appliance or appliances. If the two fuel gases have different burning characteristics and Wobbe numbers, correct burner selection is important. 

PVA was used as a temporary binder owing to its water solubility, excellent binding strength and clean burning characteristics. To prepare the PVA solution, 4 g of PVA were added to 100ml distillated water. The mixture was heated and stirred vigorously until all the PVA was dissolved in the water. This took about half an hour. Peptisation was done by addition of 5 ml 1M HN03 to the solution. Finally, the solution was refluxed for 4 hours. The PVA solution was used in the preparation of the zirconia-alumina sol-gel solution. The preparation of the PVA solution can be summarised as follows ... 

It should be noted that riobeit s Law is valid only for non-porous powders which deflagrate but do not expld. Hence, it is Inapplicable to powders which are porous such as BlkPdr, non-gelatinized, compressed NC, etc. See Burning and Burning Characteristics of Propellants for Artillery Weapons and Small Arms in Vol 2, B346-L to B347-L Refs 1) Marshall 1 (1917), 310-11 2) Perez Ara (1945), 417—18 3) S. Fordham,... 

Pressure, Influence of on Combustion of Propellants. See under Burning and Burning Characteristics of Propellants for Artillery Weapons and Small Arms in Vol 2, B346-L ff... 

BS 4735. Assessment of Horizontal Burning Characteristics of Small Specimens of Cellular Plastics and Cellular Rubber Material When Subjected to a Small Flame, BSI, London. 

Standard Method of Test of Surface Burning Characteristics of Building Materials, (similar to ASTM E-84). 

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