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Show .) area (Figures 5a and 6a), peak height (Figures 5b and 6b), filter weight (Figures 5c and 6c), and peak CO (Figures 5d and 6d). Again, due to the experimental design of the first data set, similar plots for stoichiometric ratio are identical to those for post flame oxygen flow. Figures 5 and 6 include the averaged data for each of the seven experimental conditions (denoted by +), as well as the 95 percent confidence regions around each linear model. All the data indicate decreasing response with increasing post flame oxygen flow (and stoichiometric ratio) and post flame oxygen partial pressure. Attempts were made to add additional linear and quadratic terms to the models; however, these additions did not significantly increase the variance explained. Again, note that a portion of these responses can be explained by simple dilution. A possible disadvantage to oxygen enrichment for use in hazardous waste incineration is the potential to produce high concentrations of nitrogen oxides (NOx) due to the increased temperatures and increased available oxygen. Effects of the latter may greatly exacerbate this problem if high nitrogen containing wastes are incinerated, although even if the waste contains little or no nitrogen, thermal fixation of ambient nitrogen may produce unacceptable quantities of NOx• Figure 7 presents contours of baseline nitric oxide (NO) concentration over the region examined by the first experimental set (Table I). The data are presented as measured (Figure 7a) and corrected to 7 percent oxygen (Figure 7b) in the exhaust gas. Concentrations as high as 1500 ppm (at 7 percent oxygen) were determined for high oxygen operating conditions using natural gas auxiliary fuel only. Sets 2 and 3: Corrected for Dilution Effects As stated previously, the second and third data sets (Tables II and III) 13 |