Thermal power plant Generator Hydrogen ( H2) Dryer detail. 

Ok

Ok

Ok, is it absorption type?

Ok

-15 to 20 C

Dlaltons law of partial pressure.....

Yes i Was in Sasan power from 2015 to 2019.

It is H2 dryer there is H2 & referegerant, water is not there.

H2 dew point is 3 C at pressure 2 kg/cm2

So H2 at 3 degree is in gaseous phase

Actually at 3 C water vapour achieved it's dew point and condensed H2 remains it's gaseous phase.

Why hydrogen come to dryer inlet and goes back in generator if it has same pressure at i/l and o/l of dryer

I think you are asking about how this flow established, actually this is because of arrangement of fan at Generator end which accomplished this flow.

After getting pr above 3 kg/cm3

3kg/cm2

Does the hydrogen always circulates between generator and drier? after filling in generator I have not get that 3ksc what you said

Please give reply for this?

Actually H2 dryer remove moisture traces in H2 but How you ensure avaibility of moisture in H2 ? Answer is On the basis of dew point temperature. But how fast it change you don't know that's why H2 dryer started at 3 kg/cm2 of H2.