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Show 1990 AFRC Int'l Symposium 1200 1000 > E 0. 0. 800 u c 0 u 0 600 z ~ Q) ,....; 400 ~ :J 0 200 0 0.0 Scrubbing efficiency as a function of temperature ---250 C -+-350 C - ~ - 75 0 C - - 0- - - 2 0 0 . 0 400 . 0 600 . 0 800.0 1000.0 Time, sec Figure 11 through a brief but rapid reduction. It then recovers somewhat and then continues on its descent until an equilibrium removal efficiency of approx . 48% is achieved. Solution pH is initially around 6, then lowers to an equilibrium value of approx. 3. Figures #6 & #7 are essentially the same experiment, with the inlet gas concentration ratio at 5.0 and 7.5, respectively . Equilibrium pH levels are slightly lower and NO reductions are significantly greater. Figure #8 is a sample record for a trial done at an inlet gas ratio of 7.5 with the gas sparged into a 1M HCl scrubber. Resultant outlet NO concentrations and scrubber pH levels are both very low. Similar results are found in Figure #9, where inlet C1 2 :NO ratio was 5. 0 . Figure #10 displays the results of a n=7.s stream being sparged into a 1M NaCl solution scrubber . The initial pH measurement of this trial is a little low for the solution used and may be due to some residual HCl from previous runs. A couple of characteristics exist that are common to the results of all trials. In all plotted results, after some initial reduction in outlet NO concentration, the level always discontinued its descent for a period of time, either in the form of level stabilizing or a gradual recovery of the stream concentration back towards its inlet conditions. A brief delay between apparent absorption of C12 into solution and the beginning of measured NO reduction also existed. Once equilibrium had been achieved in the system, the removal efficiency of the scrubber changed very little. Figure 11 displays the effect scrubber temperature has on the NO removal efficiencies. DISCUSSION Gas solubility in scrubber media Data for the solubility of gases in liquids is given in several references [Adams, Edrnonds (1937) Brian, et.al. (1966) Seidell, Linke(19s2) Young(1981)]. For most systems, an increase in temperature usually results in a decrease of gas solubility (as - 9- |