A method of producing lightweight clay building materials by firing mixtures of coal and clay under coal gasification conditions

摘要

A method of producing a lightweight building material, such as an aggregate, comprises mixing clay powder with a high percentage of coal dust to create areas of coal within the mixture which represent a desired density of voids, pelletising the mixture in the case of aggregate, and firing it to burn off the coal and harden the clay. The burning off of the coal leaves lightweight void areas within the hardened clay to form a lightweight building material or aggregate.