Determine the energy needed to quench a hot gas with water
Assume we have a 100,000 cubic foot per minute gas (air) stream at 700 degrees F that goes to an air pollution control device; also assume the hot air has no moisture content.

If 50 degree F cooling water is used, and the desire is to cool the hot air from 700 degrees F to 175 degrees F, how much 50 degree F water is needed to quench the gas? And what would be the final temperature of the cooling/quench water after it has cooled the gas?

Assume atmospheric pressure prevails.