| OCR Text |
Show 5.0 r----".~--~----.----~........__----__, ~ 45 c Figure 4. Time to achieve 99% conversion as a fu nction of percentage of methane at 1 atm with a mixture containing 1 % CF4, (a) ,CF3H (.) and C2F6,(.) Initial temperature is 1200 . ~ 4.0 .-J U :l .3 .5 L.. .-J .,~., .3 .0 '" '" '" ... /'" ~ 2.5 en '" '"' " '" / '" l.. '" // / /' Dashed lines are results from Figure 2 en L.. 2.0 " '" / "~'" CF :l~ - - - -';--. ~ '" Q) 1.5 '" -- -.-'- E ~ 1.0 >< o 0 .5 -0 .0 '----""'"--------------"-------...... o 5 10 15 20 25 .30 7. Methane possibilities that can be encountered during incineration. Then by suitable averaging one may arrive at a fair approximation to the actual situation. We are still assessing the possibilities, particularly with respect to PIC formation. The following represent some preliminary results on the destruction of the nlain constituents, although it appears that results are in fact effected by PIC formation. The main assumption in this scenario arises from the maintenance of the physical integrity of each plug of gas. In a real incinerator there is mixing of the gas samples. Under certain situations, reactive species are mixed with a non reacting mixture and presumably this nlay well lead to ignition. However since the overall stoichiometry is fixed, there must be other situations where unreactive gas will quench a reacting mixture. Such cancellations may \vell minimize the errors caused by this approximation. The accuracy of any simulation is directly related to that of the input data. The pertinent kinetic and thermodynamic data for incineration include the gas phase reactions involving the oxidation and pyrolysis of the fuel and the target compound(s). Our model contains about 100 species interacting through 900 reactions. We have provided some validation17 of the data base by showing its consistency with a large variety of laboratory data bearing on ignition delays, product distributions, flame velocities and other properties relatable to the kinetics of these systems. Thus although it is not possible to claim that all the rate constants are correct, probably the values are of sufficient accuracy so that nluch of the physical phenomena can be captured. 1l1ere is however one inlportant caveat. Since 15 |
