Coal containing 5.0 wt% S is burned at a rate of 1250lb_m/mm in a boiler furnace. All of the sulfur in the coal is oxidized to SO₂. The product gas is sent to a scrubber in which most of the SO₂ is removed, and the scrubbed gas then passes out of a stack. An Environmental Protection Agency regulation requires that the gas in (he stack must contain no more than 0.018lb_m S0₂/lb_m coal burned. To test compliance with this regulation a flow meter and an SO₂ analyzer are mounted in the stack. The volumetric flow rate of the scrubbed gas is found to be 2867 ft³/s, and the SO₂ analyzer reading is 37. Calibration data for the analyzer are given in the table below.

(a) Determine the equation that relates SO₂ concentration in lb_m/ft³ to the analyzer reading.

(b) Is the process in compliance with the EPA regulation?

(c) What percentage of the SO₂ produced in the furnace is removed in the scrubber?

(d) An earlier EPA regulation set a limit on the mole fraction of SO₂ in the gas emerging from the stack (as opposed to the quantity of SO₂ emitted per mass of coal burned), but a way was found to release large quantities of SO₂ from stacks without violating this regulation. Speculate on what the method of getting around the old regulation was.?

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SO₂ Analyzer Calibration Data C(g SO₂/m³ gas) 0.30 0.85 2.67 7.31 18.2 30.0 Reading (0-100 scale) 10 28 48 65 81 90