condensate reservoir dew point pressure

Dear friends

I'm really confused. I want to calculate dew point pressure by eos (PR and SRK).
I have composition of the gas including N2, H2S and CO2.
I calculate Tc, Pc and acentric factor. I'm not sure about binary interaction parameter especially for non-HC ingredients.
I have to guess initial P and find Z from EOS. what I have to do next.

can anyone guide me in this step by step please?
It's really urgent.

thank you

What kind of fluid system are you dealing with?

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From the entered gas composition and choosing an EOS, what does the eos calculate for dew point initially..?

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eos calculates fugacity and fugacity coefficient to calculate dew point in iterate process.