The present invention relates to a method for manufacturing a binder with high belite content comprising the steps: a) providing a starting material by selecting one raw material having a Ca/Si molar ratio of 1.5 to 2.5 or by mixing two or more raw materials to obtain a starting material with the Ca/Si molar ratio of 1.5 to 2.5; b) hydrothermal treatment of the starting material produced in step a) in an autoclave at a temperature of 100 to 300 C. and a retention time of 0.1 to 24h, wherein the water/solids ratio is from 0.1 to 100 to provide an intermediate product; c) annealing the intermediate product obtained in step b) in a flash calciner at 620 to 630 C., wherein the retention time is 1-30 seconds.

The invention provides novel carbonatable calcium silicate compositions and carbonatable calcium silicate phases that are made from widely available, low cost raw materials by a process suitable for large-scale production. The method of the invention is flexible in equipment and production requirements and is readily adaptable to manufacturing facilities of conventional cement. The invention offers an exceptional capability to permanently and safely sequesters CO.sub.2.

Provided herein are compositions, methods, and systems related to bimodal, trimodal, and/or multi-modal distribution of reactive vaterite cement particles.

A raw meal for a cement clinker, a cement clinker made from that raw meal and a process for producing a cement clinker are provided. The clinker contains mainly the hydraulically activate alphaH-belite polymorph and calcium sulfoaluminate (ye'elimite or C.sub.4A.sub.3?), at the low firing temperature of 1050? C., using a combination of fluoride and boron oxide.

A belite-ye'elimite-ternesite cement clinker includes: ye'elimite: 20-50 wt. %; ternesite: 24-50 wt. %; belite: 10-35 wt. %; and free-calcium sulfate (f-C$): 2-10 wt. %. The composition of cement clinker includes an appropriate amount of ye'elimite minerals, ensuring fast early hydration and high early strength of the cement clinker. The cement clinker further includes a certain amount of free-calcium sulfate (f-C$), and is characterized by its good grindability, leading to decreased energy and mechanical losses essential for clinker grinding. This environmentally conscious and energy-efficient method aligns with the global objective of reducing carbon emissions.

A hydraulic binder for a mortar composition includes at least one ladle slag having a particle size distribution by volume such that the D50 is less than 40 ?m.

A hydraulic binder for a mortar composition includes at least one ladle slag having a particle size distribution by volume such that the D50 is less than 40 ?m.

A method can include reducing calcium sulfate to calcium sulfide, converting calcium sulfide to calcium oxide, optionally using the calcium oxide to form a product, optionally oxidizing sulfur dioxide to sulfuric acid, and optionally using the sulfuric acid in fertilizer production.

The invention provides novel carbonatable calcium silicate compositions and carbonatable calcium silicate phases that are made from widely available, low cost raw materials by a process suitable for large-scale production. The method of the invention is flexible in equipment and production requirements and is readily adaptable to manufacturing facilities of conventional cement. The invention offers an exceptional capability to permanently and safely sequesters CO.sub.2.

The invention provides a process for producing a cement clinker comprising: (i) mixing one or more starting materials providing each at least one or more of CaO, SiO.sub.2, AI.sub.2O.sub.3, and Fe.sub.2O.sub.3; and, optionally, SO.sub.3, to form a raw meal comprising CaO, SiO.sub.2, AI.sub.2O.sub.3, and Fe.sub.2O.sub.3; and, optionally, SO.sub.3, wherein the molar ratios among the aforementioned oxides is given by Formula I: S(CaO).sub.1(SiO.sub.2).sub.a(Al.sub.2O.sub.3).sub.b(Fe.sub.2O.sub.3).sub.c(SO.sub.3).sub.d, wherein: a is comprised from 0.05 to 1, b is comprised from 0.1 to 0.6, c is comprised from 0.001 to 0.25, and d is comprised from 0 to 0.3 and wherein at least 35% (p/p) of the starting materials of the raw meal have a critical microwaves absorbance temperature (Tc) comprised from 15 to 650 C. and a critical microwaves absorbance time (tc) comprised from 1 min to 1 h; (ii) heating the raw meal by irradiating with microwaves during 15 min to 3 h to reach a sintering temperature comprised from 300 to 950 C.; (iii) maintaining the microwave sintering temperature of step (ii) during 1 min to 3 h by further irradiating with microwaves; and (iv) cooling the clinker obtained in step (iii).