A Method for the Manufacture of Hydraulic Binders from Water Treatment Residuals

A method for the manufacture of a high alumina hydraulic binder comprising hydrating a source of aluminium ions with a source of calcium ions in the presence of water to form mineral hydrates and subsequently heating said mineral hydrates to form said high alumina hydraulic binder.

A method for the manufacture of calcium aluminate cement comprising mixing a source of calcium ions with water treatment residuals, or other aluminium rich waste residuals, in the presence of water, in a mixing, such that mineral hydrates are formed, and subsequently heating the resulting mineral hydrates to a temperature of at least 350° C. in a thermal treatment to oxidise organic material present and to at least partially dehydrate the hydrated minerals to form the resulting cement product.

A method for the manufacture of calcium sulphoaluminate cement comprising mixing a source of calcium ions and sulphate salts with water treatment residuals, or other aluminium rich waste residuals, in the presence of water, in a mixing, such that mineral hydrates are formed, and subsequently heating the resulting mineral hydrates to a temperature of at least 350° C. in a thermal treatment to oxidise organic material present and to at least partially dehydrate the hydrated minerals to form the resulting cement product.