Abstract: A settable composition comprising (i) a cementitious component comprising at least 25% of calcium aluminate of which at least 40% is calcium monoaluminate said cementitious component optionally containing one or more particulate fillers but containing less than 10% by weight of calcium sulphate, the % being by weight being based on the weight of the cementitious component and (ii) an aqueous emulsion of an organic polymer, the amount of (ii) in relation to (i) being such as to provide a weight ratio of polymer solids to weight of (i) of from 0.5:1 to 10:1, preferably 0.6:1 to 2.5:1 or (iii) a dispersible organic polymer and where the amount of dispersible polymer is such as to give a weight ratio of polymer to weight of (i) of from 0.5:1 to 10:1, preferably 0.6:1 to 2.5:1. The cementitious component (i) preferably contains an amount of fiber effective to improve the tensile strength of coatings obtained from the settable composition but not exceeding 5% by weight of the cementitious component (i).

Abstract: A settable composition comprising (i) a cementitious component comprising at least 25% of calcium aluminate of which at least 40% is calcium monoaluminate said cementitious component optionally containing one or more particulate fillers but containing less than 10% by weight of calcium sulphate, the % being by weight being based on the weight of the cementitious component and (ii) an aqueous emulsion of an organic polymer, the amount of (ii) in relation to (i) being such as to provide a weight ratio of polymer solids to weight of (i) of from 0.5:1 to 10:1, preferably 0.6:1 to 2.5:1 or (iii) a dispersible organic polymer and where the amount of dispersible polymer is such as to give a weight ratio of polymer to weight of (i) of from 0.5:1 to 10:1, preferably 0.6:1 to 2.5:1. The cementitious component (i) preferably contains an amount of fibre effective to improve the tensile strength of coatings obtained from the settable composition but not exceeding 5% by weight of the cementitious component (i).

Abstract: A void in a mine is backfilled by a backfill slurry comprising water, an inert filler, e.g. mine tailings, and a binder, e.g. cement, lime or slag, to which a gelling agent, e.g. sodium silicate, is added just before placement.

Abstract: A dry composition comprising an aluminous cement and a calcium sulphate, and preferably an accelerator and a water soluble fluoride may be reacted with water in a wide range of proportions to form a rapid setting material which develops high compressive strength.

Abstract: A composition to be mixed with water to form rapidly a lightweight high strength set product, as well as a method of placing such compositions at a desired location and the reaction produced. The composition comprises about 1 to about 10% by weight of a gas producing agent which will release gas under acidic conditions, about 1 to about 15% by weight of a rapid setting agent which will form an acid solution in water, and an effective amount of a particulate pozzolan.

Abstract: A capsule contains in separate compartments the interactive components of a self setting composition which according to the invention comprise as base component a paste of high alumina cement, water and a source of CaO and SiO.sub.2 --e.g. as a single source granulated blast furnace slag; and as a catalyst component a paste of lime, water and a water soluble lithium salt. When reacted the components form a set cement containing hydrated phases typical of an OPC.

Abstract: A vortex combustion furnace (1) for the production of glass beads or the like is generally cylindrical and has an outlet flue (24) at its upper end. A burner (13) at the lower end burns a gas/air mixture. Secondary air is introduced into the chamber through tangential air inlets (16) and creates a vortex (71) within the chamber. Tertiary air is introduced through a ring of angled nozzles (71) surrounding the burner further to swirl the flame. The vortex has a top-hat temperature profile with a central heating region with a temperature in excess of 1000.degree. C. and a surrounding cooling region with a temperature not much above ambient. Glass cullet is supplied to a fluidized bed (53) and then entrained in a pipe (44) to be injected into the chamber. The cullet follows a spiral path in the vortex, is heated, melts to form glass beads, is then cooled and finally is collected after striking the wall of the chamber.

Abstract: A vortex combustion furnace (1) for the production of glass beads is generally cylindrical and has an outlet flue (24) at its upper end. A burner (13) at the lower end burns a gas/air mixture. Secondary air is introduced to the chamber through tangential air inlets (16) and creates a vortex within the chamber. The vortex has a top-hat temperature profile with a central heating region with a temperature in excess of 1000.degree. C. and a surrounding cooling region with a temperature not much above ambient. Glass cullet injected into the chamber follows a spiral path in the vortex, is heated, melts to form glass beads, is then cooled and finally is collected after striking the wall of the chamber.