Propane flame properties

For a while till now, our research group has been involved in studies of the properties of limit flames. Most of the results reported in this chapter were obtained for propane flames, under normal atmospheric conditions, in 300 mm long channels, with a square cross-section. The experimental procedure was described previously [25]. A flame propagating through a stationary mixture in a quenching tube or quenching channel can be characterized by the parameters defined in Figure 6.1.1. 

Jarosinski, J., Podfilipski, J., and Fodemski, T., Properties of flames propagating in propane-air mixtures near flammability and quenching limits. Combust. Sci. Tech., 174 167, 2002. 

Properties Colorless, flammable gas boiling at -48°C (about -54°F). Burns with a yellow sooty flame, so it can be substituted for propane in liquid petroleum gas (LPG). 

The measurements were performed with a FLAPHO 4 flame photometer (Carl Zeiss Jena) using a propane-air flame. The influence of sulfate, chloride, and phosphate ions and the mutual influence of alkali metal ions on the determination of potassium and sodium ions were investigated. Anions were selected on the basis of previous experiments to determine their interference properties. The multifactorial plan was realized in the concentration levels represented in Tab. 10-4. 

Flames formed from air combined with the lighter hydrocarbons, such as methane, propane, butane, or natural gas, behave in a very similar fashion with similar temperatures, similar chemical properties, etc. 

Properties Colorless, liquefied gas. D (liquid) 0.576 (15/15C), boiling range -39 to -20C, flame temperature (in oxygen) 2925C. A mixture containing 60-66.5% methylacetylene and propadiene, with the balance being propane and butane. 

Table 4.12 shows a comparison of safety-relevant thermo-physical and combustion properties of hydrogen with those of methane, propane and gasoline [26]. The flammability limits are affected by temperature, as shown in Figures 4.9 and 4.10, so that a preheated mixture has considerably wider limits for coherent flames [27]. An increase in pressures up to lOkPa has only a small effect. Water vapor has a strongly inhibiting influence on the oxyhydrogen reaction. 

Properties Colorless gas, nat. gas odor easily liquefied under pressure at R.T. noncorrosive sol. in ether, alcohol, chloroform, org. soivs. si. sol. in water, acetone m.w. 44.09 sp.gr. 0.513 (0 C, as liq.), 1.56 (0 C, as vapor) f.p. -189.9 C b.p. -42.5 C flash pt. -104 C Toxicology OSHA PEL7TWA1000 ppm simple asphyxiant narcotic in high cones. overexposure may cause dizziness, disorientation, excitation liq. propane may cause frostbite to skin and eyes TSCA listed Precaution Flamm. dangerous fire hazard exposed to heat, flame explosive limits in air 2.4-9.5% vigorously reactive with oxidizers explosive as vapor exposed to heat or flame explosive with CIO violent exothermic reaction with barium peroxide, heat Hazardous Decomp, Prods. Heated to decomp., emits acrid smoke and irritating fumes... 

It shows the main paths of polar function groups (carboxyl, hydroxyl, and carbonyl) formation, what stipulate change properties of a surface. The composite dependence with an extreme character between intensity of processing and change of properties of a surface is observed. As an example on Figure 11 are given the test data of adhesion of ink to a surface of PE, treated by a flame of the propane at it different dose (the air delivery was constant) [56]. 

Another old treatment method for PP is the flaming process. As a standard gas for the burner, a mixture of propane and air with a mixture ratio of 1-20 or a bit higher air content is used. The flame should not burn or melt parts of the surface. The burner should be guided over the surface at a distance of approximately 20 mm or more with a velocity of 0.12 m/s. Under these conditions with the propane air mixture ratio of 1-20, the best surface properties are produced. Also in this case, the effect is an oxidizing mechanism. With this method only the parts of the surface which are in direct contact with the flame are treated. 

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