An activator composition for a non-OPC hydraulically-active material comprises CaO or lime and a polycarboxylate-ether-based (PCE) superplasticiser, and is mixable with a hydraulically active material comprising ground granulated blast furnace slag (GGBS) and/or pulverized fuel ash (PFA) to form a cementitious binder. The cementitious binder does not comprise any Portland cement and is, therefore, more environmentally friendly.

The present invention relates to an inorganic binder system comprising blast furnace slag, and at least one solid alkali metal silicate, wherein the inorganic binder system is obtainable by co-grinding a mixture comprising the blast furnace slag and the at least one solid alkali metal silicate.

The present invention provides a method of preparing a recycled cementitious material by a phosphogypsum-assisted carbon sequestration pretreatment process. The method includes: (1) placing 100 mass parts of phosphogypsum, 1 to 2 mass parts of grinding aid, 10 to 20 mass parts of sodium-containing alkali component, 150 to 300 mass parts of zirconia balls, and 150 to 300 mass parts of water into a wet grinding tank for wet grinding. After 10 min to 30 min of wet grinding, introducing CO.sub.2 at a flow rate of 1.5 to 2.2 mass parts/min to keep a temperature of a wet grinding slurry below 40 C. When the wet grinding slurry reaches pH=10, ending the wet grinding and sieving out a wet grinding slurry; (2) mixing the wet grinding slurry with 700 to 1000 mass parts of slag and 100 to 350 mass parts of water to obtain a recycled cementitious material.

Provided herein are methods and compositions utilizing one or more cementitious replacement materials, one or more alkaline activating materials, and, optionally one or more bonding materials and/or one or more setting time enhancer materials.

A novel engineered concrete binder composition providing overall reduced clinker factor and improved binding properties. The said concrete binder composition includes a primary binder in a ratio of 10-60 weight percent and a secondary binder in a ratio of 40-90 weight percent. The said primary binder is selected from a primary material group having spontaneous hydration property. The said secondary binder is selected from a secondary material group having induced hydration property.

The present invention discloses a method of preparing an alkali activation material by using red mud-based wet grinding and carbon sequestration and an application thereof. The preparation method includes: (1) adding water, red mud, a crystalline control agent, and a grinding aid into a wet grinding carbon sequestration apparatus to perform wet grinding, and simultaneously introducing CO.sub.2 until a slurry pH reaches 7 to 7.5; and removing wet grinding balls by a sieve to obtain a slurry A; (2) adding carbide slag, water and a water reducer to a wet planetary ball grinder tank for wet grinding, and removing wet grinding balls by a sieve to obtain a slurry B; (3) taking 50 to 80 parts of the slurry A and 20 to 50 parts of the slurry B and mixing them to obtain an alkali activation material.

A cementitious binder comprises at least 90% by weight of a hydraulically-active material comprising ground granulated blast furnace slag (GGBS) and/or pulverised fuel ash (PFA), and at least 0.1% by weight of CaO in an activator composition for the hydraulically-active material. The cementitious binder does not comprise any Portland cement and is, therefore, more environmentally friendly. The binder further comprises a superplasticiser such as a polycarboxylate ether (PCE). A concrete, mortar, grout, screed or render may be formed from a mixture of the cementitious binder, aggregate particles, water and superplasticiser.

An inorganic, non-Portland cement-based construction material is provided. The material may include blast furnace slag material, volcano rock flour, alkali-based powder, and sand. Other materials having various ratios may also be included.

High-strength concrete-like FG blends and methods for producing them are described. The blend includes FG, hydraulic cement, additional alkali material, and pozzolanic material. The blend further includes an admixture used in the formulation of concrete. The blend further includes an aggregate. The aggregate is a coarse aggregate or a fine aggregate.

The disclosure provides an ultralow-carbon clinker-free cement, prepared from the following raw materials: granulated blast-furnace slag, gypsum and calcium oxide-based materials. The granulated blast-furnace slag accounts for 65%-95% of the total weight of the raw materials, the gypsum accounts for 4.5%-34.5% of the total weight of the raw materials, and the balance is the calcium oxide-based material. A weight percentage of calcium oxide and/or calcium hydroxide in the total weight of the raw materials is controlled to be 0.05%-0.75%. The disclosure further provides a method for preparing the ultralow-carbon clinker-free cement and application of the ultralow-carbon clinker-free cement in the preparation of concrete, mortar or cement products. The ultralow-carbon clinker-free cement of the disclosure has the advantages of high early strength, ultrahigh long-term strength, low shrinkage, carbonation resistance, low carbon emissions, etc.