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Air Sparging and Groundwater Recirculating Wells 29 I <br /> adjusted to yield 0 concentration at the time of arrival at the surface or exit from <br /> the reactor: <br /> rvoc = -KLavoc(C-CS) (7) <br /> Where rvoc = rate of VOC mass transfer, µg/ft3•h (µg/m3•h) <br /> KLavoc = overall VOC mass transfer coefficient, Uh <br /> C = concentration of VOC in liquid <br /> Cs = saturation concentration of VOC in liquid µg/ft3 (µg/m3} <br /> The saturation concentration of a VOC in wastewater is a function of the <br /> partial pressure of the VOC in the atmosphere in contact with the wastewater: <br /> C9 <br /> _ He (8) <br /> C <br /> Therefore: Cs =H,*CS (9) <br /> Where Cg = concentration of VOC in gas phaseµg/ft3 (µg/m3) <br /> = saturation concentration of VOC in liquid µg/ft3 (Kg/m) <br /> ) <br /> 't <br /> Hc = Henry's Constant x: <br /> F <br /> The rate of decomposition is now adjusted to equal the total HVOC k <br /> entering the bubble. <br /> SET: [H,•Cs] = Ko d0d[Csl (10) <br /> 3 <br /> Therefore surface concentration or exit condition=0. <br /> 3 <br /> The critical factors for speed of reaction become ozone concentration, <br /> f <br /> HVOC concentration, partial pressure, bubble size, and adequate catalyst <br /> g <br /> presence. The reaction is presented as: t <br /> k <br /> H2O+HC-2C13 +03 =2CO2 +3HC1 01} <br /> An assumed ozone injection rate of 48 grams per hour (1.0 moles/hour) <br /> yields the following: <br /> A <br /> 1.0 mol/hr H2O+ 1.0 mol/hr HC203 + 1.0 mol/hr 03= 5 <br /> 2.38 mol/hr CO2 +2.98 mol/hr HCl (12) <br /> 2 <br /> i <br /> ii <br /> Dowideit and von Sonntag (1998) recently confirmed the product yield <br /> ratios at 2.38 moles CO2 and 2.87 moles HCl, very close to the expected values. ' <br /> d <br /> . 1 <br />