About 20 years ago, when I was a project engineer and not a university professor, the company I worked for received an invitation from CST to bid for the design of the steel mill circulating water treating plant and the powerplant.
The circulating water is the one that cools the steel coming out the rolling mills (billets, plates, shapes, pipe etc.) This water flows at very high rates and can not be filtered in filters found in water treating plants. It must be filtered in high velocity filters called deep bed filters.
Problem is that this water contains mill scale that can not pass through the filtering material, so the mill scale must be separated before the water flows into the filters. This is done in the so called mill scale pits.
After filtration, the water passes through a cooling tower before it goes back to the circulating cicle.

Unfortunately, we lost in both bids: the power and the circulating water treating plants. Of course, you can't win all the bids in which you take part.
Giovanni S. Crisi