The significant increase in demand for mineral resources in conjunction with expected future rise in prices and bottleneck in supply leads to a rising demand for refractory raw materials. Consequently, expanding the use of secondary raw materials in refractory industry will result in a higher demand for new recycling concepts. The challenge is to develop technically and economically feasible processing techniques to recover valuable materials in high quality and suffi cient quantity. For this reason investigations concerning the characterisation of raw materials are of special importance. Using the example of spent magnesia carbon refractories these investigations are described in more detail.
Refractories are ceramic materials, which are applied in high-temperature industrial processes (e.g. > 1,200 °C) where extreme conditions dominate, e.g. aggressive media like gases and slags, thermal, mechanical and chemical stress. They are especially used in plants of the basic industry. The biggest consumers of refractories are the iron and steel industry, nonferrous metal industry, glass industry, cement and lime industry, ceramic industry as well as the sectors chemistry, petrochemistry and environment (RHI AG 2014).The production of refractories is based on mineral raw materials. Main primary raw materialsare magnesite, graphite and bauxite, which belong to the group of critical or potentially critical raw materials. Presently, landfilling is the main type of disposal. Recycling of spent refractories is only possible to a limited extent and is mostly connected with 'downcyclingâ€. Up to now, for the production of new refractories only selected secondary raw materials in a certain quality and grain size canbe applied, which are blended with primary raw materials. In order to ensure the required properties of refractory products, the use of recycled refractory materials is limited. The proportion of recycled materials that can be used for the production of bricks is about 5-10 %, the proportion of recycled materials that can be used for the production of mixes is about 20-30 %. For high-Quality products the use of recycled materials is only possible in small quantities.
Copyright: | © Lehrstuhl für Abfallverwertungstechnik und Abfallwirtschaft der Montanuniversität Leoben |
Quelle: | Depotech 2014 (November 2014) |
Seiten: | 6 |
Preis: | € 3,00 |
Autor: | Univ.-Prof. Dipl.-Ing. Dr. mont. Helmut Flachberger Dipl.-Ing. Sandra Strubel |
Diesen Fachartikel kaufen... (nach Kauf erscheint Ihr Warenkorb oben links) | |
Artikel weiterempfehlen | |
Artikel nach Login kommentieren |
Hochlauf der Wasserstoffwirtschaft
© Lexxion Verlagsgesellschaft mbH (8/2024)
Überblick über und Diskussion der Maßnahmen zum beschleunigten Ausbau
der Wasserstoffinfrastruktur in Deutschland
Die innerstaatliche Umsetzung des Pariser Klimaschutzübereinkommens
- ein Rechtsvergleich
© Lexxion Verlagsgesellschaft mbH (8/2024)
Like all public international law treaties, the Paris Climate Accords rely on national law for their implementation. The success of the agreement therefore depends, to a large extent, on the stepstaken or not taken by national governments and legislators as well as on the instruments and mechanisms chosen for this task. Against this background, the present article compares different approaches to the implementation of the Paris Agreement, using court decisions as a means to assess their (legal) effectiveness.
Klimaschutzrecht und Erzeugung erneuerbarer Energien in der Schweiz
© Lexxion Verlagsgesellschaft mbH (8/2024)
Verschachtelte Gesetzgebung unter politischer Ungewissheit