There is a process of CO.sub.2 mineralization with natural mineral phases with prevalent alkaline-earth metals silicate content producing a mixture of magnesium carbonate, amorphous silica and other possibly non-reacted or non-mineralizable phases. The material thus obtained, after being washed with water, develops pozzolanic properties and can be used for formulating cements.

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.

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 present invention describes a hydraulic cement composition, process and use thereof, wherein the composition comprises a hydraulic cement composition with increased resistance against carbon dioxide (CO.sub.2) for application in reservoirs such as oil and gas and carbon capture and storage (CCS) wells; with improved performance of cement paste formulations as a material for application in primary, secondary cementing, recovery and/or plugging operations, of reservoirs/wells that operate with high CO.sub.2 content; as a technological alternative to guarantee the integrity of wells in CO.sub.2-rich environments for long periods of time, without any additional intervention to the already current operational procedures for cementing wells, and with cost reduction in relation to class G cement (currently, the main raw material); and sufficient chemical resistance to carry out enhanced oil (EOR) and gas (EGR) recovery by injecting high levels of CO.sub.2, increasing reservoir pressure throughout the extraction period of hydrocarbon reservoirs.

The present invention describes a hydraulic cement composition, process and use thereof, wherein the composition comprises a hydraulic cement composition with increased resistance against carbon dioxide (CO.sub.2) for application in reservoirs such as oil and gas and carbon capture and storage (CCS) wells; with improved performance of cement paste formulations as a material for application in primary, secondary cementing, recovery and/or plugging operations, of reservoirs/wells that operate with high CO.sub.2 content; as a technological alternative to guarantee the integrity of wells in CO.sub.2-rich environments for long periods of time, without any additional intervention to the already current operational procedures for cementing wells, and with cost reduction in relation to class G cement (currently, the main raw material); and sufficient chemical resistance to carry out enhanced oil (EOR) and gas (EGR) recovery by injecting high levels of CO.sub.2, increasing reservoir pressure throughout the extraction period of hydrocarbon reservoirs.

An admixture for cement, including: A) a comb polymer comprising the following partial structural units or consisting thereof: a) a mole fractions of a partial structural unit S1 of formula (I)

##STR00001## b) b mole fractions of a partial structural unit S2 of formula (II)

##STR00002## where M, R.sup.u, R.sup.v, m and R.sup.1 are as defined in the invention; and B) optionally, alkanol amine.

The admixture for cement can provide remarkable improvement effects, particularly in milling aid effect, water-reducing properties, slump, fluidity and strength, for cements containing inferior or cheap mineral aggregate.

An admixture for cement, including: A) a comb polymer comprising the following partial structural units or consisting thereof: a) a mole fractions of a partial structural unit S1 of formula (I)

##STR00001## b) b mole fractions of a partial structural unit S2 of formula (II)

##STR00002## where M, R.sup.u, R.sup.v, m and R.sup.1 are as defined in the invention; and B) optionally, alkanol amine.

The admixture for cement can provide remarkable improvement effects, particularly in milling aid effect, water-reducing properties, slump, fluidity and strength, for cements containing inferior or cheap mineral aggregate.

A method for producing a pozzolanic product by hydrothermal treatment of a feedstock including silicate, aluminate, and/or aluminosilicate materials, and a source of calcium ions, wherein the feedstock has a molar ratio of Ca:(Si+Al) from 0.4 to 1.2 and a maximum content of hydrated cement paste of 10 wt.-%, to provide a hydrate product, and subsequent carbonation of the hydrate product to provide a pozzolanic product including calcium carbonate and silica gel, alumina gel and/or silica-alumina gel. A pozzolanic product is obtainable by the method. The pozzolanic product is used as a supplementary cementitious material for manufacturing a composite cement including the pozzolanic product and a hydraulic cement.

A method for producing a pozzolanic product by hydrothermal treatment of a feedstock including silicate, aluminate, and/or aluminosilicate materials, and a source of calcium ions, wherein the feedstock has a molar ratio of Ca:(Si+Al) from 0.4 to 1.2 and a maximum content of hydrated cement paste of 10 wt.-%, to provide a hydrate product, and subsequent carbonation of the hydrate product to provide a pozzolanic product including calcium carbonate and silica gel, alumina gel and/or silica-alumina gel. A pozzolanic product is obtainable by the method. The pozzolanic product is used as a supplementary cementitious material for manufacturing a composite cement including the pozzolanic product and a hydraulic cement.

The present invention relates to a rapid-setting hydraulic binder composition and, more specifically, to a hydraulic binder composition, which contains tricalcium aluminate (C3A) and dodecacalcium heptaaluminate (C12A7), and thus is rapidly set, has an easily adjustable setting time, and is bio-friendly.