Utilization of steel slag in a California cement plant

A cement production facility in the coastal California area utilizes a patented process to introduce steel slag directly into the feed end of the kiln. Steel slag shares many common characteristics of the cement feedstock and chemically combines with the entire mix. Not a raw material; it has already been heated to 3000 degrees Fahrenheit, and having a chemical composition quite similar to Portland cement clinker, the raw mill feed is proportioned to a chemical composition that will result in the correct clinker chemistry. This paper highlights plant production achievements, quality control and operational challenges associated with the usage of slag in clinker production. This paper also discusses theories of NO_x and CO₂ emission reductions per unit clinker produced, in addition to an overview of the slag handling and feeding system design and implementation process at the plant.