Process for agglomerating expanded perlite fines

摘要

Expanded lightly milled perlite fines are mixed with aqueous alkali metal silicates and the wet mixture is dried at temperatures of from 600 DEG F up to 1400 DEG F in a moving air stream to form agglomerates which are useful as filteraids. The agglomerates may be heat treated in an indirect fired rotary kiln to further reduce the water solubility, and may be separated into size factions either before or after the heat treatment.