Method for producing particulate refractory compositions for use in the production of casting molds and cores, their uses and regenerated mixtures for heat treatment

摘要

A method of preparing a particulate refractory composition for use in the production of a casting mold or core from a waste casting mold or core formed of a binder containing a refractory material and water glass is described, the method comprising the steps of: a waste casting mold or Providing crushed material from the core or preparing crushed material from a spent casting mold or core, wherein the crushed material aggregates refractory material particles and/or particles having a cured water glass binder on the surface. ), mixing the crushed material with a particulate amorphous oxide containing silicon dioxide in an amount of 85% by weight or more based on the total amount of the particulate amorphous oxide to provide a mixture, and the mixture is 400 °C or higher. Heat treatment at a temperature above. It also describes the application, the recycled mixture, and the method of making the casting mold or core.