摘要:
An improved process for the preparation of aggregates for use with mixtures of various carbonatable substances, in particular mixtures comprising pulverised fuel ash and/or steel slag. The mixtures also comprise a carbonatable binder. The process comprises the steps of a. blending a combination of two carbonatable wastes, b. mixing the blended carbonatable waste with a carbonatable binder, c. mixing the blended carbonatable waste and binder with water, and d. carbonating the damp blended carbonatable waste in the presence of carbon dioxide.
摘要:
An improved process for the preparation of aggregates for use with mixtures of various carbonatable substances, in particular mixtures comprising pulverised fuel ash and/or steel slag. The mixtures also comprise a carbonatable binder. The process comprises the steps of a. blending a combination of two carbonatable wastes, b. mixing the blended carbonatable waste with a carbonatable binder, c. mixing the blended carbonatable waste and binder with water, and d. carbonating the damp blended carbonatable waste in the presence of carbon dioxide.
摘要:
A building product is made from granular material and a binder that includes steel slag. A process for making the building product includes combining the granular material and the binder and then curing the combined granular material and binder with carbon dioxide. A building material includes a mixture of steel slag and a silica-rich material. The steel slag and silica-rich material is treated by heating. The silica-rich material may be waste glass and/or fly ash. A process for making the building material includes mixing the steel slag and silica-rich material and further heating the mixture.
摘要:
A method of producing a mainly carbonate bonded article includes a step of providing an alkaline granular material having one or more alkaline earth metal silicate phases. The method includes a step of compacting the granular material to obtain a compact of the granular material. The porosity of the compact is smaller than or equal to 37% by volume. The intrinsic permeability of the compact is at least 1·10−12 cm2. The method also includes a reacting step arranged to form at least 5% by weight of carbonates (CO32−), by reacting the granular material with carbon dioxide in the presence of water, thus transforming the compact into the article. In the reacting step, the compact, being unsaturated with moisture at the beginning of the reacting step, is brought in an atmosphere having carbon dioxide. The atmosphere is at a temperature of at least 70° C. and at a pressure of at least 0.5 MPa. The pressure is also higher than the saturated vapor pressure of water at the temperature. As a result, at least a portion of the carbonates are formed by reaction of the one or more alkaline earth metal silicate phases. Articles are also obtained by the method.
摘要:
Disclosed is a heavyweight concrete composition using slag byproducts, including: ground granulated blast furnace slag; slow-cooled electric-arc-furnace oxidizing slag or atomized steel slag used as a fine aggregate; a coarse aggregate; water; and a chemical admixture based on 100 parts by weight high-early-strength cement. Thus, the heavyweight concrete composition contains a large quantity of steel slag and blast-furnace slag that are byproducts in iron-making and steel-making processes, thereby remarkably reducing an amount of emission of carbon dioxide and maximizing the recycling of waste resources for preserving the natural environment. As a result, an eco-friendly heavyweight concrete product can be made.
摘要:
The present invention relates to a process for producing a granular material 26 for mixing with at least a hydraulic binding agent and with water to produce mortar or concrete. This process comprises at least an aggregation step and a carbonation step. In the aggregation step, steel slag particles from at least a fine fraction 24 of steel slag, in particular a fine fraction of steel slag containing a significant amount of γ-dicalcium silicate, are aggregated into larger grains so as to form a coarser granular material 25. In the carbonation step, said aggregated particles in said coarser granular material 25 are carbonated by means of carbon dioxide so as to produce a carbonated granular material 26. The present invention also relates to a carbonated granular material of aggregated steel slag particles containing a significant amount of γ-dicalcium silicate, in particular at least 3 wt. %, preferably at least 5 wt. % and more preferably at least 7 wt. %, and bound within each grain by a solid matrix containing at least calcium and/or magnesium carbonates.
摘要:
A main component of cement is cement clinker, which is produced from a mixture of raw materials containing calcium oxide, silicon dioxide, aluminium oxide and iron oxide by means of mixing, grinding and burning. According to the invention, the mixture of raw materials consists of a calcareous component and converter slag, the converter slag being added in a proportion of up to 30% by weight. Natural resources of raw materials can hereby be preserved and the carbon dioxide output during burning of the cement clinker can be reduced.
摘要:
Cementitious materials including slag and geopolymer can be added to conventional cement compositions, such as Portland cement, as a partial or total replacement for conventional cement materials. The slag may comprise silicates and/or oxides of calcium, silicon, magnesium, iron, aluminum, manganese, titanium, sulfur, chromium and/or nickel. The geopolymer may comprise aluminum silicate and/or magnesium silicate. In a preferred embodiment, curing of concrete materials by the action of water on the cementitious materials is enhanced with the addition of an activator component selected from calcium bromide, calcium nitrate, calcium nitrite, calcium chloride, calcium oxide, and sodium bromide.
摘要:
A more economical and light-color cellular concrete is provided by the replacement of Portland cement with ground glass powder in a cellular lightweight concrete mixture and the resulting method to make cellular concrete products. The use of ground glass also increases the stability of the cellular lightweight concrete mixture during the foaming or aeration process. The products are suitable for use in structural applications, insulation, and as a lightweight aggregate.
摘要:
A process for the conversion of iron bearing residues from the non-ferrous process industry into a synthetic rock, comprising the following steps: 1 part of the wet residue is mixed with at least 0.1 parts by weight of crushed blast furnace slags and with at least 0.1 parts by weight of crushed converter slags; water is added to the mixture to obtain a stiff paste; and the paste is allowed to harden, while kept wet, to such an extent that the resulting rock is usable for construction purposes.