Nucor Steel operates a contact cooling water system for their hot strip mill in Crawfordsville, Indiana. The system was designed to operate in the range of 14,000 gpm to 16,000 gpm. Nucor later installed a third pump to increase the capacity to between 20,000 and 22,000 gpm. The hot mill scale pit performance was marginal at the lower flow rates, but with the increased flow the scale pit was significantly under performing, leading to increased total suspended solids (TSS) and oil & gas carry over into the cooling tower basins and cold well.
McKim & Creed conducted a hot mill cooling water balance; specified and located flow meters to better monitor the hot mill cooling water system; improved hot mill scale pit performance by designing a better baffle system to reduce velocities; reduced slugs of oil into the sand filter front-face effluent piping; and improved oil drum removal system.