Bublon®
Closed-cell expansion of perlite sands yield novel product properties for lightweight construction materialsSummary: Conventional expansion of perlite, an acidic, glassy volcanic rock yields granular products with an open-celled surface and a high dust content. This can be attributed to bursting during expansion of the perlite particles. The production of expanded perlite products with a closed glazed surface is based on a completely new process, which was developed to series maturity in the scope of a cooperative research project between Binder+Co AG and the Department of Mineral Processing at Montanuniversität Leoben as the Bublon® process. With the use of BUBLON granulate, new product properties can be obtained for a large number of industrial applications. For instance, thanks to the comparatively low water absorption of the new BUBLON granulates, considerable cost benefits can result in the processing of these to machine-applied renders or insulation boards for the interior or exterior of buildings.
1 Introduction
The expansion of perlite was discovered by accident in Arizona in 1946. Already back then the suitability of this new product for the production of insulating building material was recognized. Today expanded perlite products are used in a wide range of industries, although the construction materials industry is still the main area of application. For the production of expanded perlite, the state of the art entails heating in vertical expansion furnaces fired with natural gas. Owing to the direct feed of the perlite sand into the flame, the expanded perlite particles burst caused...