METHOD FOR PRODUCING EXPANDED GLASS GRANULES AND EXPANDED GLASS GRANULES AND THE USE THEREOF

摘要

The invention relates to a method for producing expanded glass granules. To this end, starting materials are provided, comprising 80% to 95% glass and 5% to 20% sodium silicate hydrate having a water of crystallization content between 1 and 2 wt%, in relation to the solids content. After the glass is ground, the starting materials are mixed, the ground starting materials are granulated into raw granules, and the raw granules are mixed with a release agent, the mixture comprising the raw granules and the release agent is heated to a processing temperature. In a first partial step, the pores on the surfaces of the particles of the raw granules are closed, and in a second partial step, the water of crystallization is dissolved from the sodium silicate hydrate and caused to thermally expand, whereby the particles of the raw granules expand and form the expanded glass granules. The invention further relates to expanded glass granules comprising loose expanded glass particles, the majority of which consists of glass, have expanded cavities, comprise a densely sintered surface made of glass and exhibit water absorption of less than 10%. Finally, the invention relates to the use of such expanded glass granules as an additive in mortar or as a filler in rinsing liquid.