0We need to remove \(\mathrm{H}_{2} \mathrm{~S}\) and \(\mathrm{CO}_{2}\) from \(1000.0 \mathrm{kmol} / \mathrm{h}\) of a water stream at \(0^{\circ} \mathrm{C}\) and \(15.5 \mathrm{~atm}\). 0Inlet liquid contains \(0.0024 \mathrm{~mol}_{2} \mathrm{H}_{2} \mathrm{~S}\) and \(0.0038 \mathrm{~mol} \%\) \(\mathrm{CO}_{2}\). We desire a \(99.0 \%\) recovery of \(\mathrm{H}_{2} \mathrm{~S}\) in the gas stream. Pure nitrogen at \(0^{\circ} \mathrm{C}\) and \(15.5 \mathrm{~atm}\) is used to strip out \(\mathrm{H}_{2} \mathrm{~S}\) and \(\mathrm{CO}_{2}\). Nitrogen flow rate is 3.44 \(\mathrm{kmol} / \mathrm{h}\). A staged countercurrent stripper will be used. Assume water flow rate and air flow rate are constant. Data are in Table 12-1. Note: Watch your decimals.

Table 12-1

a. Determine the \(\mathrm{H}_{2} \mathrm{~S}\) mole fractions in the outlet gas and liquid streams.

b. Determine the number of equilibrium stages required.

c. Determine the \(\mathrm{CO}_{2}\) mole fraction in the outlet liquid stream.

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TABLE 12-1. Henry's law constants H for Eq. (12-3) for CO2, CO, and H2S in water. H is in atm/mole fraction. TC CO2 CO HS 0 728 35,200 268 LO 5 876 39,600 315 10 1040 44,200 367 15 1220 48,900 423 20 1420 53,600 483 25 1640 58,000 545 30 1860 62,000 609 35 2090 65,900 676 40 2330 69,600 745 45 2570 72,900 814 50 2830 76,100 884 60 3410 82,100 1030 70 84,500 1190 80 84,500 1350 90 84,600 1440 100 84,600 1480