Utilities Design Rules :  Cooling air supply – Electricity

1. Steam: 15-30 psig, 250―275˚F; 150 psig, 366˚F; 400 psig, 448˚F; 600 PSIG, 488˚F or with 100-150˚F superheat.
2. Cooling water: supply at 80-90˚F from cooling tower, return at 115-125˚F; return seawater at 110˚F, return tempered water or steam condensate above 125˚F.
3. Cooling air supply at 85-95˚F; temperature approach to process, 40˚F.
4. Compressed air at 45, 150, 300, or 450 psig levels.
5. Instrument air at 45 psig, 0˚F dewpoint.
6. Fuels: gas of 1000 Btu/SCF at 5―10 psig, or up to 25 psig for some types of burners; liquid at 6 million Btu/barrel.
7. Heat transfer fluids: petroleum oils below 600˚F, Dowtherms below 750˚F, fused salts below 1100˚F, direct fire or electricity above 450˚F.
8. Electricity: 1-1000 Hp, 220―550V; 200―2500 Hp. 2300―4000V.