A natural gas stream flows at $40m^3{s}^{-1}(1(atm),20C)$ and contains $1\%$ of $H_{2}S.$ We wish to

scrub it to reduce the $H_{2}S$ concentration to $4ppm.$ The gas is scrubbed at a pressure of $100$atm

and $20C.$ Assuming that we use water as the scrubbing agent, estimate the required water flow

rate. The Henry's Law constant for $H_{2}S,H_{H2S}=493$ atm @$20C.$ We make the requirement

that at the bottom of the absorber $y_i^{**}=0\mathrm{.}8y_i.$ Hint: See Figure below.

$(10$ marks$)$

$($Gas nit$)$

Typical operating line diagram