Gerdau Wilton Facility Plan & Filtration Design
One of the largest steel producers in North America, Gerdau has locations across the country including a steel mill in Wilton, Iowa. The company manufactures special steel products for the construction, automotive, agricultural, and energy markets.
Gerdau’s Wilton plant received a new NPDES permit from the Iowa Department of Natural Resources (IDNR) for its industrial wastewater that contained more restrictive iron and copper discharge limits, along with a compliance schedule to meet water quality standards.
The existing treatment process at the Gerdau plant used settling ponds to remove iron and copper. Sampling data revealed that this treatment method would not meet the new effluent limits and upgrades to the industrial wastewater treatment system was in order.
Gerdau’s Wilton plant selected Shive-Hattery to design an additional treatment system that would not only meet the effluent limits, but also fit into the available space. Evaluation and design lead to a new pressure sand filter system to treat the manufacturing plant’s industrial discharge water. The industrial wastewater is first aerated to oxidize the iron and copper, then pumped through sand filters to remove the suspended material. The two-stage sand filter is fully automated to maintain the appropriate pond level, conduct backwashing to keep filter media clean, and provide fault notifications at the earliest sign of problems.
Through collaboration with Shive-Hattery, the Gerdau industrial wastewater system was upgraded with new filters that allowed Gerdau’s Wilton steel mill to meet the more stringent effluent limits within the compliance schedule of the new NPDES permit.