Zepazuri

Reuse of waste in dewatering cones (019-PROTS-2022)

Objectives

This project has the support and collaboration of the Vice-Ministry of Environmental Sustainability of the Basque Government, and its objective is to modify the process of preparation of cones used to de-corrupt the spoons used in the refining process..

We are managers of black slag and white slag:

  • Black slag is 100% valorized, being used in the manufacture of concretes, sub-bases, etc.
  • The white slag is treated for reuse as raw material in cement plants. However, this process generates a non-reusable waste: the “white slag recycling reject”, which is usually sent to landfill.

The cones are used to dump white slag, which is rich in lime. Traditionally, black slag was added to the bottom for two purposes:

  1. To avoid humidity (risk of explosion when pouring the broth).
  2. Prevent steel debris from sticking to the bottom of the cone.

With the new methodology:

  • The cones are dried.
  • The black slag is removed in a segregated cone, allowing its reuse.
  • The scrap is used as cone bottom, transforming it into reusable white slag.

Advantages of the Project

  • Reduction of the volume of waste sent to landfill.
  • Reuse of black slag as such, avoiding mixing it with rejects.
  • Conversion of rejects into white slag within the parameters required by cement plants.
  • Elimination of the operation of crushing the bottom of the cone.
  • Improvement of the quality of the white slag sent to cement plants.

Partners

Department of Economic Development, Sustainability and the Environment of the Basque Government

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