62 results about "Ground granulated blast-furnace slag" patented technology

The invention discloses a method for reducing and recovering iron from steel slag and preparing an auxiliary cementing material from secondary slag. The method comprises the following steps: uniformlymixing the converter steel slag, a reducing agent and a component adjusting material, performing melting back under the condition that high temperature forms a reducing atmosphere, performing water quenching cooling, separating the metal iron, drying the secondary slag, and performing grinding to obtain the auxiliary cementing material. The method disclosed by the invention can reduce and recoverthe iron in the steel slag by 80% or more; and the prepared auxiliary cementing material is similar to granulated blast furnace slag powder, technical indexes of the auxiliary cementing material meetrelevant requirements of a standard ''ground granulated blast furnace slag used for cement and concrete'' GB/T18046-2008 in China, and the auxiliary cementing material can be used as a cement mixed material and a concrete admixture. The method disclosed by the invention reduces Fe2O3 and FeO in the steel slag into the metal iron for recovery and utilization, changes chemical components of the steel slag to make the components similar to those of granulated blast furnace slag, improves gelling activity, and realizes overall, high-added-value, and more effective large-scale comprehensive utilization of the steel slag.

Provided is a cement admixture which gives cured cement concrete that imparts excellent non-corrodible properties to the reinforcing bars present therein, has resistance to external infiltration of chloride ions, and can be inhibited from becoming porous because Ca-ion eluviation occurs little and that has self-healing ability. Also provided is a cement composition. The cement admixture is characterized by comprising a calcium ferroaluminate compound which is based on CaO, Al2O3, and Fe2O3, has a Fe2O3 content of 0.5-15 mass%, and has a CaO2Al2O3 structure, the CaO/Al2O3 ratio being in the range of 0.15-0.7 by mole. It is preferred that the admixture have a degree of fineness of 2,000-7,000 cm2/g in terms of Blaine specific surface area and that a latent hydraulic substance and/or a pozzolanic substance (pozzolanic substance and the like) be used in combination with the calcium ferroaluminate compound. The pozzolanic substance and the like preferably comprise one or more substances selected from a group consisting of ground granulated blast furnace slag, fly ash, silica fume, metakaolin, incineration ash of pulp sludge, incineration ash of sewage sludge, and waste glass powder. It is preferred that the ratio of the calcium ferroaluminate compound to the pozzolanic substance and the like be from 10/1 to 1/10 by mass. The cement composition comprises cement and the cement admixture.

The invention discloses a novel alkali-activated cementitious material for 3D printing. The novel alkali-activated cementitious material for the 3D printing is prepared from following raw materials inpercentage by weight: 20%-46% of ground granulated blast furnace slag, 7%-22% of nickel iron slag, 7%-14% of lithium slag, 7%-14% of red brick powder, 2%-3.5% of a solid alkali activator, 0.3%-0.7% of attapulgite, 0.3%-0.7% of bentonite, 0.07%-0.14% of plant fiber and 28%-31% of water. The novel alkali-activated cementitious material for the 3D printing has good workability, has good cohesive property and high stability due to the characteristics of quick setting, rapid hardening and early strength and completely meets the material performance requirement of the 3D printing technology.

A slag cement includes ground granulated blast furnace slag and ground limestone combined in a predetermined weight ratio. Limestone and granulated blast furnace slag (GBFS) are fed to a grinding apparatus in a ratio of about 3-5% limestone by weight. The limestone is a cheaper raw material than the GBFS, resulting in a reduction in production costs for the slag cement. Moreover, the addition of limestone to the GBFS surprisingly results in improved compressive strength.

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.

In sulfate resistant cement obtained by mixing ground granulated blast furnace slag, Portland cement, and high-dissolution rate gypsum for raising the sulfate resistance, the high-dissolution rate gypsum differs in grain size and specific gravity from the Portland cement, so uniform mixture is not easy. To obtain sulfate resistant cement exhibiting homogeneous initial solidification, it is important to uniformly mix the blast furnace slag, Portland cement, and high-dissolution rate gypsum.

Therefore, by premixing ground granulated blast furnace slag with an alumina content of 12 to 17.5% with high-dissolution rate gypsum and then mixing in Portland cement, it is possible to obtain uniformly mixed sulfate resistant cement.

At this time, the high-dissolution rate gypsum may be hemihydrate gypsum, type III anhydrous gypsum, or anhydrous gypsum with a specific surface area of 8000_Blaine or more.

A slag-based binder has at least one slag, optionally at least one CO₃-containing mineral powder, optionally at least one co-binder different from the slag and mineral powder, at least one activator of the water/slag reaction, optionally at least one co-activator different from the one activator, at least one chelatant and/or at least one source of chelatant, said chelatant being preferably a scale inhibitor, and, optionally, at least one superplasticizer different from the chelatant. A kit is provided to make the binder. The binder is combined with an aggregate to make a dry concrete or mortar. A method for the preparation of a wet formulation (binder/water or concrete-mortar/water) is disclosed as is method of manufacturing buildings or civil engineering works or elements thereof, coatings, fillers, screeds, tiles, adhesives and/or internal or external insulation systems from the wet formulation. The binder is a substitute to OPC-based compositions and is environmentally friendly.

The present invention concerns a hydraulic binder comprising a ground blast furnace slag in an amount comprised between 30% and 95% by mass on the binder, Portland cement clinker in an amount equal to or greater than 5% by mass on the binder, and at least one sulphate as activator, characterised in that said slag has the following properties and composition by mass: grinding fineness greater than 4000 cm2/g Blaine glass content greater than 80% SiO₂: 30-40% Al₂O₃: 9-13% CaO: 34-42% with a (CaO+MgO)/(Al₂O₃+SiO₂) ratio greater than 1; and in that said sulphate is contained in a total amount, expressed as SO₃, comprised between 0.6% and 4.5% by mass on the binder.

Mixed cement containing mainly ground granulated blast furnace slag with an alumina ratio of 12 to 17.5 mass % and Portland cement, wherein a ratio of mixture of the ground granulated blast furnace slag is made 10 to 60 mass % and wherein plaster having a specific surface area of 7000 cm²/g or more is mixed in by a ratio of 2 to 4 mass % converted to SO₃ mass. By using this mixed cement as a concrete material, it is possible to suppress expansion of the concrete even if in contact with soil containing residual sulfates over a long period.

A multi-component cementitious composition with at least a binder and a hardener component, wherein the binder component includes ground granulated blast furnace slag and water and wherein the hardener component includes a sodium silicate solution containing at least 42 wt.-%, preferably at least 45 wt.-% or sodium silicate (Na₂SiO₃). Such multi-component cementitious compositions have been found to provide excellent early strength in excess of 0.5 mPa after hardening for just 2 h with a gel time in the range of 10 to 20 s. In addition the binder components are stable or at least remixable for up to 4 d in the absence of the hardener, which makes them particularly suitable for back filled grouts.

The invention discloses a high-intensity concrete admixture. The high-intensity concrete admixture is prepared from the following raw materials in parts by weight: blast-furnace slag 200 parts, edible fungi residues 35-45 parts, gypsum 10-15 parts, gneiss 10-20 parts, shale 25-35 parts, activated carbon slag 30-40 parts, attapulgite 20-30 parts, pine and cypress ash 15-18 parts, polypropylene fibers 2-4 parts, corn stigma 0.2-0.5 part and an additive 1-3 parts. The additive consists of glutinous rice glue, starch octenylsuccinate, fish glue and glucomannan according to the weight ratio of 500: 20: 1-3: 5. The blast-furnace slag is ground granulated blast-furnace slag powder, and the Brinell specific surface area is 500-600 m(2)/kg. The high-intensity concrete admixture has the effects that the compressive property of the concrete is enhanced, the brittleness of the concrete is reduced, and the working preforamnce of the high-intensity concrete is improved.

The invention discloses a modified ecological fiber reinforced recycled aggregate lightweight wall material and a preparation method. The modified ecological fiber reinforced recycled aggregate lightweight wall material comprises the following components in parts by mass: 15-36 parts of Sorel cement, 5-15 parts of ground granulated blast furnace slag, 10-25 parts of ceramsite, 12-40 parts of recycled lightweight aggregate, 8-20 parts of pottery sand, 0.1-0.6 part of modified ecological fibers, 0.1-2 parts of foaming agents, 0.2-1.0 part of thickening agent and 10-30 parts of water. The preparation method comprises the steps of putting the Sorel cement, the ground granulated blast furnace slag, the modified ecological fibers and the thickening agent, which are required for preparation, together and stirring the materials for 8-15 minutes, then adding water and the foaming agents, which are required for preparation, to the mixture in sequence and further stirring the materials for 10-15 minutes, thus obtaining a slurry mixture. The lightweight wall material and the preparation method have the beneficial effects that the ecological fibers have good tensile deformation resistance and are lighter, so the foam concrete has toughness; China has abundant ecological plant resources, thus saving plenty of resources and being beneficial to the human living environment.

The invention discloses foundry molding sand containing blast furnace slag. The foundry molding sand is prepared from the raw materials in parts by weight: 40-55 parts of mudstone particle, 3-5 parts of waste aluminum powder, 7-9 parts of graphite powder, 6-8 parts of bentonite, 2-5 parts of plant ash, 4-6 parts of granular blast furnace slag and 8-12 parts of water. The foundry molding sand is prepared by the steps: 1) weighing the plant ash, the granular blast furnace slag and the bentonite according to the proportion, and adding water accounting for the total quantity of 35-40 percent. With the adoption of the foundry molding sand, as coal powder is not added, and straw powder and the plant ash are mainly used as antisticking additives, the cost is lowered, and the surface smoothness of a casting is also improved.

The invention discloses a durable granulated blast furnace slag building block and belongs to the technical field of a building material. The durable granulated blast furnace slag building block is prepared according to the following steps: crushing granulated blast furnace slag and sieving, thereby acquiring refined granulated blast furnace slag; mixing and stirring the acquired refined granulated blast furnace slag and sulfuric acid, soaking and filtering, thereby acquiring the pretreated granulated blast furnace slag; stirring, mixing and fermenting paper-making black liquor, chitosan solution, soybean protein powder and biogas slurry, thereby acquiring a fermentation liquor; mixing the pretreated granulated blast furnace slag and the fermentation liquor, soaking and filtering, therebyacquiring the modified granulated blast furnace slag; mixing and stirring the modified granulated blast furnace slag, gypsum, quicklime, cement, water, modified charring cocoanut fiber and silane coupling agent, thereby acquiring a mixed slurry; injecting the mixed slurry into a mold, pressing and forming, thereby acquiring a blank; placing the blank into a curing chamber and curing, thereby acquiring the durable granulated blast furnace slag building block. The durable granulated blast furnace slag building block provided by the invention has excellent mechanical properties and durability.

The invention provides a preparation method of a high-performance concrete mineral admixture. The method comprises the following steps: taking converter slag, processing the converter slag through a hot braising technology to make the granularity less than 5 mm in order to obtain hot-braised converter slag, and grinding the hot-braised converter slag to form powder with the Blaine specific surface area of 300-400 m<2>/kg in order to obtain hot-braised converter slag powder; taking granulated blast furnace slag powder, and grinding the granulated blast furnace slag powder to form powder with the Blaine specific surface area of 400-500 m<2>/kg in order to obtain granulated blast furnace slag powder; taking and grinding limestone to form powder in order to obtain limestone powder; and uniformly mixing 1-5 parts by weight of the hot-braised converter slag powder, 4-10 parts by weight of the granulated blast furnace slag powder and 0-1.6 parts by weight of the limestone powder to obtain the high-performance concrete mineral admixture. The method has the advantages of reuse of industrial wastes, resource saving, reduction of the making cost of concrete, simple process, simple operation, easiness in operation, and easiness in wide application.