The present invention relates to a system and method for the production of gypsum board using starch pellets. In accordance with the present disclosure, the starch necessary for board formation is provided in the form of starch pellets. These pellets are mixed with a gypsum slurry in a mixer. The pellets are initially insoluble and do not dissolve. However, during subsequent drying stages, the pellets become soluble and dissolve into the gypsum phase. This both provides the desired starch component and also results in the formation of voids within the set gypsum.

Methods and an associated system for processing unhardened concrete are disclosed. With these methods, the porosity of the unhardened concrete is significantly increased to decrease the strength so much that it can be easily broken up for sale or reuse. In at least one embodiment, the method includes adding a large volume of foam to the returned unhardened concrete and then mixing the foam with the returned concrete in the ready-mix concrete truck or other concrete mixing devices at any location including the jobsite, enroute to the concrete plant, or at the concrete plant. Through the mixing of foam with the returned concrete, the hydrated cement and aggregate particles are separated by large volumes of air voids, which significantly increase the porosity and dramatically reduce the strength of the returned concrete. The treated concrete is discharged and allowed to solidify in this weakened state, after which it is easily broken into loose particulate material that can be sold or reused.

Methods and an associated system for processing unhardened concrete are disclosed. With these methods, the porosity of the unhardened concrete is significantly increased to decrease the strength so much that it can be easily broken up for sale or reuse. In at least one embodiment, the method includes adding a large volume of foam to the returned unhardened concrete and then mixing the foam with the returned concrete in the ready-mix concrete truck or other concrete mixing devices at any location including the jobsite, enroute to the concrete plant, or at the concrete plant. Through the mixing of foam with the returned concrete, the hydrated cement and aggregate particles are separated by large volumes of air voids, which significantly increase the porosity and dramatically reduce the strength of the returned concrete. The treated concrete is discharged and allowed to solidify in this weakened state, after which it is easily broken into loose particulate material that can be sold or reused.

The invention provides compositions and methods for sealing subterranean spaces such as natural or induced fractures, vugs or annular spaces. The composition is composed of a base fluid consisting of a soluble alkali silicate, a gas generating additive, solids and a setting agent. The gas generating additive may be coated or uncoated. The gas generating additive may also be in the form of a slurry. In the case of coated additives, the coating may act as a retarder or an accelerator to the expansion and setting agent of the soluble alkali silica. Similarly, the choice of carrier fluid in a slurry may retard or accelerate the expansion and setting of the alkali silicate-based plug.

A geopolymer foam composition, an article comprising a geopolymer foam composition, methods for making a geopolymer foam composition, and uses of a geopolymer foam composition.

Disclosed is a composite waterproof structure comprising: an inorganic elastic undercoat layer including an inorganic material on a construction surface; a complementary reinforced fiber or chopped fiber layer in the form of a mesh in the middle of an inorganic undercoat body; a first intermediate coat layer disposed on the inorganic elastic undercoat layer; a mesh-type fiber-reinforcing sheet layer attached onto the first intermediate coat layer; first and second impregnated layers provided on the mesh-type fiber-reinforcing sheet layer; a second intermediate coat layer disposed on the first and second impregnated layers; a third intermediate coat layer provided on the second intermediate coat layer; and a first top coat layer.

A porous structure includes 3 wt % to 4.2 wt % of Mg, 14 wt % to 18 wt % of Ca, 12 wt % to 15 wt % of Si, 0.8 wt % to 1.5 wt % of Al, 0.1 wt % to 0.3 wt % of K, 0.4 wt % to 2 wt % of Fe, 7 wt % to 8.5 wt % of Na, 4.8 wt % to 7.6 wt % of B, and 48 wt % to 52 wt % of O.

A foamed colloidal silica binder having a total porosity of about 50% to about 95% by volume can be used to make porous refractory compositions and refractory articles having a porosity of about 25% to about 75% by volume. The foamed colloidal silica binder endures mixing with refractory ingredients to form the porous refractory composition, casting the refractory composition into a refractory shape, and drying the shape to form to refractory article, without significant collapsing of the foam. The resulting lightweight refractory articles are useful in a wide variety of insulating and weight-reducing applications.

A rapidly-expanding and -curing geopolymer formulation includes a liquid aqueous phase with silicate, aluminate and/or silico-aluminate precursors, an inorganic base, a monosaccharide and/or disaccharide, and a water-soluble peroxy compound. The saccharide and peroxy compound react spontaneously and rapidly in strongly alkaline conditions, producing an expanding gas and exothermic heat of reaction that drives at least an initial cure of the geopolymer formulation. The resulting foamed geopolymer formulation can be used in a variety of building and construction applications, as well as and others.

A rapidly-expanding and -curing geopolymer formulation includes a liquid aqueous phase with silicate, aluminate and/or silico-aluminate precursors, an inorganic base, a monosaccharide and/or disaccharide, and a water-soluble peroxy compound. The saccharide and peroxy compound react spontaneously and rapidly in strongly alkaline conditions, producing an expanding gas and exothermic heat of reaction that drives at least an initial cure of the geopolymer formulation. The resulting foamed geopolymer formulation can be used in a variety of building and construction applications, as well as and others.