Holcim Technology

The invention aims to substitute a part of the clinker component in cement by a (recycled) mineral material, the provision of which does not emit significant amounts of CO<2>. To this end, the invention provides a method of manufacturing a supplementary cementitious material from a mineral material such as recycled concrete fines, the method comprising the following steps: a step of grinding the mineral material; a step of chemical activation, carried out during or after the step of grinding; a step of thermal activation, carried out before or after the step of chemical activation; wherein the mineral material comprises cement paste; and wherein the step of chemical activation is carried out by contacting the mineral material with at least one activator selected from alkali metal salts. The invention further provides the supplementary cementitious material obtained by that method and the use of the supplementary cementitious material in a composite binder as well as a composite binder comprising the supplementary cementitious material. The invention also relates to a cementitious building material comprising the composite binder.

A method of producing cement clinker from a source of calcium sulfate, comprising- a first step of desulfurizing the calcium sulfate to obtain a calcium oxide containing material and sulfur dioxide, and- a second step of calcining the calcium oxide containing materials to obtain cement clinker,wherein the first and/or the second step is carried out in the presence of silica, alumina, and iron oxide containing materials,wherein the source of calcium sulfate contains 0.1-5 wt.-% fluoride salt(s) and 0.1-5 wt.-% phosphate salt(s) andwherein the first and/or the second step comprises forming fluorellestadite.

The invention refers to a method for the removal of contaminants from a flue gas (1) of a cement plant to obtain a lean gas (31), comprising a first gas washing and cooling step with a first aqueous washing fluid comprising an alkaline substance to remove sulfur oxides, halides, heavy metals, and/or particulate matter from the flue gas (1), and subsequently at least one additional gas washing and/or cooling step with another aqueous washing fluid to remove additional contaminants and/or humidity from the flue gas (1).

The invention refers to a method of manufacturing a cementitious assembly, the cementitious assembly having a layered structure wherein at least two layers of a hydraulic composition are bonded with a mineral bonding agent, the method comprising the following steps: i) placing a first layer of a hydraulic composition onto a substrate; ii) applying a mineral bonding agent onto the first layer of the hydraulic composition; iii) placing another layer of the hydraulic composition onto the mineral bonding agent; iv) allowing the at least two layers of the hydraulic composition and the mineral bonding agent to set and harden to obtain the cementitious assembly, wherein the steps ii) and iii) can be repeated several times prior to execution of step iv), and wherein the hydraulic composition comprises 15 to 50 m-% binder, in mass percentages of the hydraulic composition, and wherein the mineral bonding agent comprises, in mass percentages of the mineral bonding agent: Portland cement 35-75 m-%, preferred 45-60 m-%; fine mineral filler 2-35 m-%, preferred 5-30 m-%; sand 1-15 m-%, preferred 5-10 m-%; water reducer 0.1-5 m-%, preferred 0.25-2 m-%; and water, and further to the use of the mineral bonding agent, a cementitious assembly and the use of the cementitious assembly.

A construction board composite comprising (i) a construction board, wherein the construction board includes a first planar surface opposite a second planar surface; (ii) a plurality of pressure-sensitive adhesive zones disposed on the first planar surface, where each pressure-sensitive adhesive zone of the plurality of pressure-sensitive adhesive zones includes (a) a portion that contacts the first planar surface and (b) an exposed portion; and (iii) a release liner contacting at least a portion of the exposed portion.

A method for 3D printing of construction materials wherein a flowable composition containing hydraulic cement with low tricalcium aluminate (C3A) content (<5 wt.-%, preferably <3 wt.-%) and aggregates is conveyed to a deposition head and deposited layer-by-layer through an outlet of the moving deposition head. Prior to deposition, a yielding agent comprising aluminum chloride, its hydroxides, or mixtures thereof is added to increase the yield stress of the material compared to its state during conveyance, enabling successive layers to be placed on top of each other without deformation

The invention relates to a process for the preparation of a composite filter composition and the use of said composite filter composition in the preparation of a hydraulic composition.

The invention relates to a method for the production of a mineral foam comprising the following steps: (i) preparing a cement slurry, comprising: - a cementitious composition; - a carboxylic acid or salt thereof selected from the group consisting of a monocarboxylic acid comprising from 1 to 5 carbon atoms, a dicarboxylic acid comprising from 2 to 5 carbon atoms and mixtures thereof; and - water; wherein the carboxylic acid or salt thereof is present in an amount from 0.6% to 2.5%, preferably from 0.6% to 2%, in weight relative to the total dry weight of the cementitious composition, (ii) adding to the cement slurry obtained after step (i) a gas-forming liquid comprising a gas-forming agent to obtain a foaming slurry; (iii) applying the foaming slurry obtained in step (ii) on a support.

Method of producing a pozzolanic material, the method comprising: - providing a silico-aluminous mineral material susceptible of pozzolanic reactivity upon calcination, - subjecting the silico-aluminous mineral material to a thermal treatment step at a temperature of 500-900°C, in order to obtain said pozzolanic material, - subjecting biomass to a pyrolysis step to obtain a solid pyrolysis product and a gaseous pyrolysis product, - using at least a partial amount of the gaseous pyrolysis product as a fuel for producing thermal energy and using the same as energy input for said thermal treatment step and for said pyrolysis step.

The invention relates to a sheet lining of plastic material (1) for construction waste collecting container wherein it presents an average surface roughness (Ra) between 0.5 and 10 micrometers, preferably between 1 micrometer and 5 micrometers, and more preferably between 2 micrometers and 4 micrometers.