WHAT SHOULD BE THE DUE POINT MAINTAINED IN GAS PROCESSING INDUSTRIES?

It depend on water content target from downstream plant or the pipeline requirement to against corrosion. For lbs/mmscf, it requre deg c. You can refer to jc keeta wehe chart

Kaleem, question require more elaboration, whether you are asking about Water Dew Point or Hydrocarbon Dew Point. Water Dew Point in Sale Gas should be around18 F (depending on Contractual limits specified, normally7 lb / MMSCFD).

Hydrocarbon Dew Point contractual limit is30 F normally. If gas has more HCDP then it may requires technologies to extract the "heaviers" (like LPG recovery plants etc)