The problem of health and environmental safety in the production and operation of periclase-carbon products has been addressed using various methods, but so far, unsuccessfully. Phenolic binders, resins, and pitches of various origins, which are used in the production of products, have not been minimized without losing operational properties.
As a binder, there must be a component that cannot lead magnesium oxide to hydration not only at high temperatures but also under natural conditions. In addition, the binder must be sufficiently plastic and not contain harmful components, and also not form harmful substances during the manufacture and service of shaped periclase-carbon products. Naturally, the binder must provide the necessary operational properties of the products since these products are located and serve in the most responsible places in steel-smelting units, where they operate under very harsh temperature conditions and in direct contact with liquid and aggressive slags.
Our binder consists of thermally treated intercalated graphite with subsequent technological processing, which allows using this graphite as a binder without any additional components. In addition, such an energy-intensive process as the heat treatment of molded products is excluded.
Properties of finished products using a binder made from thermally treated intercalated graphite:
graphite content (C) is regulated depending on the required properties in the range from 5 to 15%
compressive strength, depending on the graphite content, from 30 to 50 N/mm2
open porosity is not more than 8%
apparent density, depending on the filler density and graphite content, from 2.75 to 3.1 g/cm3.
Due to its nature, intercalated graphite is more resistant to high-temperature oxidation than ordinary graphite, so we can assume that during operation, such material qualities as slag resistance and metal resistance will be higher than those of shaped products on traditional binders.
Initially, this work represented a scientific interest for us and involved finding ways to possibly expand the application boundaries of intercalated graphite. Nevertheless, the possibility of using this type of graphite as a binder and replacing it with phenolic resins, organic liquids, and plasticizers allows us to see the prospects of intercalated graphite as one of the important components in the process of manufacturing refractories. This applies not only to periclase-carbon products but also to corundum and spinel-containing products.