A gas consisting of NO2 in air is bubbled through a scrubbing tower into which water is fed at a rate of 1 m3 /h. The water absorbs most of the NO2 but none of the air. The volumetric flow rate of the feed gas, V, is determined with an orifice meter, with a differential mercury manometer being used to measure the pressure drop across the orifice. Calibration data for this meter are tabulated below:
h 50 100 200 300 400 500
V 95 142 204 247 290 302
where h is the differential height of the manometer. An electrochemical detector is used to measure the NO2 concentration in the inlet and outlet gas stream. The calibration curve for the analyzer is a straight line on a semilog plot of y (mol NO2/total mol) versus R, (analyzer reading), which passes through the points (20, 0.00166) and (90, 0.1107). The following data are taken: Feed Gas: T = 75°F Outlet Gas: R = 11.6 P = 150 psig h = 210 mm R = 82.4 a) Determine the orifice meter calibration formula by plotting V versus h on log-log scale and fitting a trendline through the data. Clearly indicate the units on the constants in the resulting formula. Turn in the calibration curve. b) Determine the NO2 calibration curve formula from the two points given above. Again, clearly indicate the units on the constants in the resulting formula. c) Calculate the mole fraction of NO2 in the liquid effluent stream (neglect the small quantity of water that leaves with the exit gas). d) How much NO2 is removed each hour from the feed gas?
A gas consisting of NO2 in air is bubbled through a scrubbing tower into which water is fed at a rate of 1 m3 /h. The water absorbs most of the NO2 but none of the air. The volumetric flow rate of the feed gas, V, is determined with an orifice meter, with a differential mercury manometer being used to measure the pressure drop across the orifice. Calibration data for this meter are tabulated below:
h 50 100 200 300 400 500
V 95 142 204 247 290 302
where h is the differential height of the manometer. An electrochemical detector is used to measure the NO2 concentration in the inlet and outlet gas stream. The calibration curve for the analyzer is a straight line on a semilog plot of y (mol NO2/total mol) versus R, (analyzer reading), which passes through the points (20, 0.00166) and (90, 0.1107). The following data are taken: Feed Gas: T = 75°F Outlet Gas: R = 11.6 P = 150 psig h = 210 mm R = 82.4 a) Determine the orifice meter calibration formula by plotting V versus h on log-log scale and fitting a trendline through the data. Clearly indicate the units on the constants in the resulting formula. Turn in the calibration curve. b) Determine the NO2 calibration curve formula from the two points given above. Again, clearly indicate the units on the constants in the resulting formula. c) Calculate the mole fraction of NO2 in the liquid effluent stream (neglect the small quantity of water that leaves with the exit gas). d) How much NO2 is removed each hour from the feed gas?