SciTech Connect

Title: Recycling galvanized steel: Operating experience and benefits

Recycling galvanized steel: Operating experience and benefits In response to the increase in consumption of galvanized steel for automobiles in the last decade and the problems associated with remelting larger quantities of galvanized steel scrap, a process is being developed to separate and recover the steel and zinc from galvanized ferrous scrap. The zinc is dissolved from the scrap in hot caustic using anodic assistance and is recovered electrolytically as dendritic powder. The dezinced ferrous scrap is rinsed and used directly. The process is effective for zinc, lead, and aluminum removal on loose and baled scrap and on all types of galvanized steel. The process has been pilot tested for batch treatment of 900 tonnes of mostly baled scrap. A pilot plant to continuously treat loose scrap, with a design capacity of 48,000 tonnes annually, has been in operation in East Chicago, Indiana since early in 1993. The first 450 t of scrap degalvanized in the pilot plant have residual zinc below 0.01% and sodium dragout below 0.01%. Use of degalvanized steel scrap decreases raw materials, environmental compliance, and opportunity costs to steel- and iron-makers. Availability of clean degalvanized scrap may enable integrated steel producers to recycle furnace dusts to the sinter plant and EAF shops to more » produce flat products without use of high quality scrap alternatives such as DRI, pig iron, or iron carbide. Recycling the components of galvanized steel scrap saves primary energy, decreases zinc imports, and adds value to the scrap. The quantities of zinc available by the year 2000 from prompt and obsolete automotive scrap win approach 25% of zinc consumed in the major automotive production centers of the world. Zinc recycling from galvanized steel scrap, either before or after scrap melting, will have to be implemented. « less
Authors: ; ;
Publication Date:
OSTI Identifier:10185263
Report Number(s):ANL/ES/CP--80360; CONF-9310158--1
ON: DE93018580
DOE Contract Number:W-31109-ENG-38
Resource Type:Conference
Resource Relation:Conference: Zinc `93,Hobart (Australia),10-13 Oct 1993; Other Information: PBD: [1993]
Research Org:Argonne National Lab., IL (United States)
Sponsoring Org:USDOE, Washington, DC (United States)
Country of Publication:United States
Language:English
Subject: 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; SCRAP METALS; RECYCLING; STEELS; MATERIALS RECOVERY; ZINC; ELECTROLYSIS; PILOT PLANTS; METAL INDUSTRY; REMOVAL; IRON COMPOUNDS; DISSOLUTION; DEMETALLIZATION 320305; 400105; INDUSTRIAL WASTE MANAGEMENT; SEPARATION PROCEDURES