Water at 1 atm is being used to remove 65% of the CO2 from a gas stream via absorption. The inlet gas stream is 100mol/h and consists of 8 mol% CO2 and the balance nitrogen. How many equilibrium stages would be required if we operate at 1.5 (S/G)min? Henrys law constant for CO2 in water is 1640 atm/mol frac.

2

Explanation:

Without mincing words, let's dive straight into the solution to the question above. We are given the following information or parameters which is going to aid in solving this problem:

Amount Of CO2 to be removed from a gas stream due to absorption = 65%, amount of the inlet gas stream = 100 mol/h, amount of the CO2 = 8 mol%, and the Henrys law constant for CO2 in water = 1640 atm/mol frac.

STEP ONE: Determine the mole ratio for the inlet gas and the outlet gas.

The mole ratio of the inlet gas = 8/92 = 0.087 and the mole ratio of outlet gas = 8 × 0.35/92 = 0.03.

NB; the 0.35 is the amount remaining after 65% of CO2 has been removed that is 100% - 65% = 35% =0.35.

STEP TWO: The next step here is to determine the value for the mass balance and hence, the absorption factor.

A × 0.087 = A × 0.03 + C × [0.087/1640]. = C/A║[min] = 1075.47.

Thus, 1.5 C/A ║[min] = 1613.2.

The absorption factor = 1613.2/1640 = 0.984 =  1 [approximately].

STEP THREE: Determine the number of equilibrium stages that would be required if we operate at 1.5 (S/G)min.

Thus, the equilibrium stages would be required if we operate at 1.5 (S/G)min = 0.087 - 0.03/ 0.03 - 0 = 1.9 = 2 [approx.]

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6