Module 2: Characteristics of Gases - Oxygen Basis Conversions - Answers

#1: A power plant has a mass emission rate of 100 lb_m/min of SO₂ at a 10% oxygen level. What is its mass emission rate corrected to a 7% standard oxygen level?

: Answer: 100 lb_m/min; Only concentration data and gas flow rate data are corrected, not mass data. Concentration can be diluted by ambient air. The gas flow rate of the gas stream can be described with or without the dilution air entering the system. Regardless of these changes, the mass of the pollutant being emitted is constant.; The conversions of concentration data and gas flow rate data are performed simply to facilitate unit-to-unit comparisons and aid in emission calculations. These mathematical procedures obviously do not change the mass quantities emitted.

#2: When a pollutant concentration is corrected to a standard oxygen level, does its concentration increase or decrease? See equation below and Table 1.

: Answer: As Table 1 shows, the answer depends on whether the measured oxygen concentration is higher or lower than the standard oxygen level. This fact can be reasoned from the following equation.; This relationship is shown graphically as follows:; This relationship is shown graphically as follows: