Alkali activated concrete compositions containing natural pozzolan, ground granulated blast furnace slag, alkali activators such as an alkali hydroxide and an alkali silicate, and optionally fine and coarse aggregates. Alkali activated concretes made therefrom and methods of making such concretes are also specified. The inclusion of ground granulated blast furnace slag provides significantly superior mechanical strength (e.g. compressive strength) to the alkali activated concretes within 12-24 hours of curing at 30-60 C.

Provided are a granulated blast-furnace slag activator and a method of manufacturing the same. The granulated blast-furnace slag activator includes, in percent by weight, the following raw materials: 62% to 95% of gypsum and 5% to 38% of high belite sulfoaluminate cement clinker. Also provided is a method of manufacturing cement by mixing the granulated blast-furnace slag activator with granulated blast-furnace slag at a certain ratio.

Alkali activated concrete compositions containing natural pozzolan, ground granulated blast furnace slag, alkali activators such as an alkali hydroxide and an alkali silicate, and optionally fine and coarse aggregates. Alkali activated concretes made therefrom and methods of making such concretes are also specified. The inclusion of ground granulated blast furnace slag provides significantly superior mechanical strength (e.g. compressive strength) to the alkali activated concretes within 12-24 hours of curing at 30-60 C.

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.

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.