Solidifying red mud contg. aluminium and iron hydroxide(s),etc.

摘要

Solidifying water-contg. red mud contg. aluminium and iron-hydroxide and hydroxyl:sodalith comprises adding a Ca-contg. additive and a reactive inorganic salt to the mud and chemically reacting the hydroxides and sodalith with the Ca of the additive and the anions of the salt to sparingly soluble crystalline hydrate phases to bond water to the solid material. The novelty is that less than 0.2 mol.% sulphate is added to the red mud and solidifying the reaction mixt. to a decomposable solid material. Also claimed is a process for the mfr. of solid building bricks or moulds having high mechanical strength and good stability towards environmental influences, made from the red mud.