The present invention belongs to the technical field of metallurgical solid waste resource utilization, and particularly relates to acidification and carbonization coupling modified steel slag as well as a preparation process and an application thereof. The process specifically includes the following steps of adopting acetic acid, tributyl phosphate, ethanolamine and a NaOH and Ca(OH).sub.2 emulsion as reaction reinforcing agents, and modifying the steel slag together with CO.sub.2-rich lime kiln flue gas. The process for modifying the steel slag through acidification and carbonization coupling provided in the present invention has the advantages of simple reaction conditions and no need of high-pressure CO.sub.2, additionally, the carbonation reaction rate can be greatly increased, and f-CaO and f-MgO in the steel slag can be effectively eliminated.

The present invention belongs to the technical field of metallurgical solid waste resource utilization, and particularly relates to acidification and carbonization coupling modified steel slag as well as a preparation process and an application thereof. The process specifically includes the following steps of adopting acetic acid, tributyl phosphate, ethanolamine and a NaOH and Ca(OH).sub.2 emulsion as reaction reinforcing agents, and modifying the steel slag together with CO.sub.2-rich lime kiln flue gas. The process for modifying the steel slag through acidification and carbonization coupling provided in the present invention has the advantages of simple reaction conditions and no need of high-pressure CO.sub.2, additionally, the carbonation reaction rate can be greatly increased, and f-CaO and f-MgO in the steel slag can be effectively eliminated.

A basic oxygen furnace slag treatment method includes the steps of mixing basic oxygen furnace slag with an active aqueous solution and then keeping the mixture thus obtained under an enclosed environment for reaction and then employing a solid-liquid separation procedure to separate solid phase from liquid phase. Since basic oxygen furnace slag has strong alkaline, the method of the invention overcomes the problem that directly discharging basic oxygen furnace slag will cause environmental pollutions. The basic oxygen furnace slag treatment method avoids a secondary pollution, and can turn waste into treasure, bringing a number of economic benefits.

Disclosed is a method of fabricating a construction element, the method comprising the manufacturing of a construction element including a slag, wherein the slag is comprising, on a dry basis and whereby the presence of a metal is expressed as the total of the metal present as elemental metal and the presence of the metal in an oxidized state, a) at least 7% wt and at most 49% wt of iron, Fe, b) at most 1.3% wt of copper, Cu, c) at least 24% wt and at most 44% wt of silicon dioxide, SiO.sub.2, d) at least 1.0% wt and at most 20% wt of calcium oxide, CaO, e) at least 0.10% wt and at most 1.50% wt of zinc, Zn, f) at least 0.10% wt and at most 2.5% wt of magnesium oxide, MgO, and g) at most 0.100% wt of lead, Pb. Further disclosed are improved construction elements comprising the slag.

Disclosed is a method of fabricating a construction element, the method comprising the manufacturing of a construction element including a slag, wherein the slag is comprising, on a dry basis and whereby the presence of a metal is expressed as the total of the metal present as elemental metal and the presence of the metal in an oxidized state, a) at least 7% wt and at most 49% wt of iron, Fe, b) at most 1.3% wt of copper, Cu, c) at least 24% wt and at most 44% wt of silicon dioxide, SiO.sub.2, d) at least 1.0% wt and at most 20% wt of calcium oxide, CaO, e) at least 0.10% wt and at most 1.50% wt of zinc, Zn, f) at least 0.10% wt and at most 2.5% wt of magnesium oxide, MgO, and g) at most 0.100% wt of lead, Pb. Further disclosed are improved construction elements comprising the slag.

An aqueous solution containing 30 ppm or more of carbon dioxide is brought into contact with a steel-making slag to elute phosphorus and calcium contained in the steel-making slag into the aqueous solution. Subsequently, carbon dioxide is removed from the aqueous solution to precipitate a mixture comprising a phosphorus compound and a calcium compound. In this manner, a mixture comprising a phosphorus compound and a calcium compound and containing phosphorus in an amount of 1% by mass or more in terms of phosphorus atom content can be produced.

An aqueous solution containing 30 ppm or more of carbon dioxide is brought into contact with a steel-making slag to elute phosphorus and calcium contained in the steel-making slag into the aqueous solution. Subsequently, carbon dioxide is removed from the aqueous solution to precipitate a mixture comprising a phosphorus compound and a calcium compound. In this manner, a mixture comprising a phosphorus compound and a calcium compound and containing phosphorus in an amount of 1% by mass or more in terms of phosphorus atom content can be produced.

Compositions and methods for treating waste water produced by copper mining operations are described herein. Slag from steel making operations and other industrial waste materials that include alkali metal and/or alkaline earth elements have been found to both raise pH of the waste water and also reduce arsenic content. Following such treatment the spent slag or industrial waste can be utilized as a source of valuable metals or incorporated into stabilized building materials.

Compositions and methods for treating waste water produced by copper mining operations are described herein. Slag from steel making operations and other industrial waste materials that include alkali metal and/or alkaline earth elements have been found to both raise pH of the waste water and also reduce arsenic content. Following such treatment the spent slag or industrial waste can be utilized as a source of valuable metals or incorporated into stabilized building materials.

A mineralizer composition for Pidgeon silicothermic process for smelting magnesium consists of fluorite and a boron-containing compound. Amounts of the fluorite and the boron-containing compound meet the following equation:

M.sub.fluo-original=(1−x)M.sub.fluo+(m)(x)M.sub.B,

where, M.sub.fluo-original is a mass of the fluorite required in a conventional Pidgeon silicothermic process in which no boron-containing compound is introduced to replace a fraction or all of the total fluorite, M.sub.fluo is a mass of the fluorite in the composition, M.sub.B is a mass of the boron-containing compound in the composition, 0.5≤x≤1, and 2≤m≤8. A Pidgeon silicothermic process for smelting magnesium is also provided, which employs the mineralizer composition. The composition and process of the disclosure enable reduction and even avoidance of dust pollution caused by fluorite-containing magnesium slag.