Description:TECHNICAL FIELD
The present disclosure relates to the field of steel slag compositions and their use in construction materials. It also relates to a method for producing steel slag compositions. Particularly, the present disclosure relates to all aspects of steel slag compositions comprising steel slag and an amine and optionally an inorganic compound.

BACKGROUND OF THE DISCLOSURE
Production of cement is associated with release of a large amount of carbon dioxide. It is estimated that for production of ordinary Portland cement (OPC), 2% of global energy and 5% of industrial energy is consumed and for producing one ton of OPC, at least 0.75 tons of Green House Gases (of which CO2 accounts for 0.5 Tons) are emitted which is a major pollutant that deteriorates the environment.

Materials containing substantial amounts of soluble silicates, alumino silicates, or ferro silicates are termed as supplementary cementitious materials (SCMs) and are used as partial replacement of clinker in cements or as partial replacement of cement in concrete. Traditionally, materials such as blast furnace slag or fly ashes have been used for many decades as SCMs and they play a major role in reducing the carbon footprint associated with cement and concrete production. To reduce this carbon footprint further, development of new sources of SCMs has become increasingly important.

With increase in the rate of industrialization, more and more industrial waste is getting generated everyday which is getting dumped in landfills and disposal of these industrial wastes have been a major problem and concern for the industry. Use of industrial wastes like ground granulated blast furnace slag (GGBFS), copper slag, and fly ash have been explored as sources of SCMs. For example, the patent document KR101138243 discloses ready-mixed concrete compositions comprising various types of industrial wastes that improve compressive strength of the concrete. It discloses a powdered admixture which can be added to a ready-mixed concrete wherein the powdered admixture comprises 25-35 weight % of building stone micro powder, 30-35 weight % of limestone powder, 15-20 weight % of fly ash, and 15-20 weight % of blast furnace slag. US20190002349 discloses an admixture for enhancing early age strength comprising a liquid suspension of colloidal silica, siloxane, and polycarboxylate polymer cement dispersant. US20180312445 discloses use of quarry fines and/or limestone powder to reduce clinker content of cementitious compositions. CN1557763 discloses a process for preparation of high-performance concrete using steel slag powder and GGBFS. CN104446041 discloses a method for producing superfine slag powder by using copper smelting secondary slag. CN106977150A discloses a preparation method for cement based composite material comprising an admixture of steel slag, sodium formate, wollastonite, and acetic acid. CN103553402 discloses the use of activated phosphorous slag and method of making thereof.

However, there is a need to explore alternate, more beneficial and environment friendly compositions which can be employed as a replacement in construction materials. The present disclosure attempts to address this need by providing steel slag compositions that can be effectively employed as SCMs.

STATEMENT OF THE DISCLOSURE
The present disclosure relates to a steel slag composition for use in a construction material comprising steel slag and an amine. In some embodiments, the steel slag has a particle size of about 2 microns to about 45 microns.

The present disclosure also relates to a steel slag composition for use in a construction material comprising steel slag, an amine, and an inorganic compound. In some embodiments, the steel slag has a particle size of about 2 microns to about 45 microns.

The present disclosure further relates to a construction material comprising a steel slag composition, wherein the steel slag composition comprises steel slag and an amine; or the steel slag composition comprises steel slag, an amine, and an inorganic compound.

The present disclosure also relates to method for preparing steel slag compositions comprising mixing steel slag and an amine. In some embodiments, an inorganic compound is added to a mixture of steel slag and an amine to prepare the steel slag composition.

BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES
Figure 1 shows an exemplary methodology employed in preparing the steel slag compositions and construction materials (concrete) of the present disclosure and their plant/field trials.

Figure 2 shows an exemplary embodiment of a process for making a steel slag composition according to an embodiment of the present disclosure.

Figure 3 shows a graph of Cold Compressive Strength (CCS) values for M30 grade concrete comprising 25% by weight of a steel slag composition as replacement to fly ash.

Figure 4 shows a graph of CCS values for M30 grade concrete comprising 35% by weight of a steel slag composition as replacement to fly ash.

Figure 5 shows a graph of CCS values for M30 grade concrete comprising a steel slag composition as 25% replacement to GGBFS.

Figure 6 shows a graph of CCS values for M50 grade concrete comprising a steel slag composition replacing 5% Metakaolin.

Figures 7 shows X-ray diffraction (XRD) peaks confirming the reactivity and presence of peaks of C3S and C2S for ground LD slag and the presence of additional peaks of ettringite and hemicarboaluminate apart from C3S and C2S in the case of activated LD slag.

DETAILED DESCRIPTION OF THE DISCLOSURE
With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity. The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results. Throughout this specification, the word “comprise”, or variations such as “comprises” or “comprising” or “containing” or “has” or “having”, or “including but not limited to” wherever used, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

Reference throughout this specification to “one embodiment” or “some embodiments” means that a particular feature, structure or characteristic described in connection with the embodiment may be included in at least one embodiment of the present disclosure. Thus, the appearances of the phrases “in one embodiment” or “in some embodiments” in various places throughout this specification may not necessarily all refer to the same embodiment. It is appreciated that certain features of the disclosure, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the disclosure, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

As used herein, the term “steel slag” is a by-product obtained in the process of steel making. Steel slag encompasses basic-oxygen-furnace (BOF) slag, electric-arc-furnace (EAF) slag, and ladle-furnace slag.

In some embodiments, steel slag is the basic oxygen furnace slag and refers to the slag produced during the separation of molten steel slag from impurities in steel-making basic oxygen furnaces such as a Linz and Donawitz converter (LD converter). In some embodiments, in a basic oxygen furnace (BOF), pig iron and scrap are melted and fluxes of lime or dolomite are added to form molten steel slag. To take out the impurities of melting steel, high pressure oxygen is injected. In the presence of high pressure oxygen, impurities from the molten steel slag combine with the lime or dolomite and float on top of the molten steel slag. The floating impurities are tapped into a slag pot and solidify on cooling to produce “steel slag”. The steel slag comprises free metallic slag and non-metallic slag. The free metallic slag can be magnetically separated from the non-metallic slag. In some embodiments, the steel slag is the “non-metallic” steel slag.

In some embodiments, the steel slag is an LD slag obtained from the basic oxygen process carried out in a LD converter. In some embodiments, the steel slag is the non-metallic LD slag.

In some embodiments, steel slag comprises SiO2, Al2O3, Fe2O3, CaO, MgO, SO3, and insoluble residue. In some embodiments, steel slag comprises one or more of the compounds in the amounts listed in Table A.

Table A
CaO SiO2 Al2O3 MgO MnO Fe (t) P2O5 C S CaO (Free Lime)
43-50 14-22 0.5-7 2-8 0.2-14 10-20 0.5-4 1-2 0.1-0.5 2.4-5.0

The term “about” as used herein encompasses minor variations of the specified value. These minor variations would be apparent to one of ordinary skill in the art in the context of the invention.

An objective of the present disclosure is to provide efficient utilization of steel making by-products.

The steel slag compositions of the present disclosure can be employed as additives to construction materials. Accordingly, another objective of the present disclosure is to provide better additives for construction materials.

Yet another objective of the present disclosure is to provide environment-friendly additives for construction materials.

Yet another objective of the present disclosure is to provide low-cost additives for construction materials.

Yet another objective of the present disclosure is to provide compositions for replacing existing additives such as ground-granulated blast furnace slag, fly ash, metakaolin, wholly or partly.

Yet another objective of the present disclosure is to provide additives for construction materials that improve the strength of the construction material.

To address the limitations discussed above and to meet the aforesaid objectives, the present disclosure provides steel slag compositions for use in a construction material. In some embodiments, the steel slag composition comprises steel slag and an amine. In some embodiments, the steel slag composition comprises steel slag, an amine, and an inorganic compound. In some embodiments, the steel slag in the composition has a particle size of about 2 to about 45 microns.

In some embodiments, the amine is an organic amine. In some embodiments, the organic amine is an alkanol amine including monoalkanol amine, dialkanol amine, and trialkanol amine. In some embodiments, the alkanol amine is selected from the group consisting of triethanol amine (TEA), triisopropanol amine (TIPA), monoethanol amine, diethanol amine, monoisopropanol amine, diisopropanol amine, diethanol isopropanol amine and combinations thereof. The steel slag compositions of the present disclosure comprise steel slag and any of the amines described herein. For example, in some embodiments, the steel slag composition comprises steel slag and triethanol amine (TEA). In some embodiments, the steel slag composition comprises steel slag and triisopropanol amine (TIPA). In some embodiments, the amine is a combination of two or more amines described herein. For example, in some embodiments, the steel slag composition comprises steel slag and an amine, wherein the amine is a combination of TEA and TIPA.

In some embodiments, the steel slag compositions comprise steel slag having a particle size of about 2 to about 45 microns and any of the amines described herein. For example, in some embodiments, the steel slag composition comprises steel slag having a particle size of about 2 to about 45 microns and TEA. In some embodiments, the steel slag composition comprises steel slag having a particle size of about 2 to about 45 microns and TIPA. In some embodiments, the steel slag composition comprises steel slag having a particle size of about 2 to about 45 microns and a combination of two or more amines described herein. For example, in some embodiments, the steel slag composition comprises steel slag having a particle size of about 2 to about 45 microns, TEA and TIPA.

In some embodiments, the amine is present in the composition in an amount of about 0.05% to about 1%, including values and ranges thereof, by weight of the composition. In some embodiments, the amine is present in the composition in an amount of about 0.05%, 0.075%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or about 1% by weight of the composition. In some embodiments, the amine is present in the composition in an amount of at least 0.1% by weight of the composition. In some embodiments, the amine is TIPA and is present in the composition in an amount of 0.1% by weight of the composition. In some embodiments, the amine is TEA and is present in the composition in an amount of 0.05% by weight of the composition. In some embodiments, the steel slag composition comprises a combination of two or more amines, wherein each amine is present in any of the amounts described herein. For example, in some embodiments, the steel slag compositions comprise about 0.05% TEA and about 0.05% TIPA by weight of the composition.

In some embodiments, the composition comprises steel slag in an amount of about 99% to about 99.95%, including values therebetween, by weight of the composition. In some embodiments, the steel slag is present in an amount of about 99%, 99.1%, 99.2%, 99.3%, 99.4%, 99.5%, 99.6%, 99.7%, 99.8%, 99.9%, or about 99.95%, by weight of the composition. In some of these embodiments, the steel slag has a particle size of about 2 to about 45 microns.

In some embodiments, the steel slag compositions of the present disclosure comprise steel slag in an amount of about 99% to about 99.95% and an amine in an amount of about 0.05% to about 1% by weight of the composition. For example, in some embodiments, the steel slag composition comprises steel slag in an amount of about 99.95% and an amine in an amount of about 0.05% by weight of the composition. In some embodiments, the steel slag composition comprises steel slag in an amount of about 99.9% and an amine in an amount of about 0.1% by weight of the composition. In some embodiments, the steel slag composition comprises steel slag in an amount of about 99.5% and an amine in an amount of about 0.5% by weight of the composition. In some embodiments, the steel slag composition comprises steel slag in an amount of about 99.3% and an amine in an amount of about 0.7% by weight of the composition. In an exemplary embodiment, the steel slag composition comprises steel slag in an amount of about 99.9% and TEA in an amount of about 0.1% by weight of the composition. In an exemplary embodiment, the steel slag composition comprises steel slag in an amount of about 99.9% and TIPA in an amount of about 0.1% by weight of the composition. In an exemplary embodiment, the steel slag composition comprises steel slag in an amount of about 99.9% and a combination of TEA and TIPA in an amount of about 0.1% by weight of the composition. In an exemplary embodiment, the steel slag composition comprises steel slag in an amount of about 99.9%, TEA in an amount of about 0.05% and TIPA in an amount of about 0.05% by weight of the composition. In some of these embodiments, the steel slag has a particle size of about 2 to about 45 microns.

It is hypothesized that the amine works as a chelating ligand by promoting surface dissolution of iron from the steel slag by complexation and/or weakening interatomic bonds in the vicinity of iron thereby facilitating detachment of iron and formation of binding phases. In some embodiments, an alkali metal salt of a hydrocarboxylic acid is used as a chelating ligand. For example, in some embodiments, alkali metal salts of a hydrocarboxylic acid such as citric acid or tartaric acid can be used as a chelating ligand in the compositions of the present disclosure. Exemplary alkali metal salts of citric acid that can be used in the composition of the present invention include sodium citrate, potassium citrate, lithium citrate, rubidium citrate, and caesium citrate. Exemplary alkali metal salts of tartaric acid that can be used in the composition of the present invention include sodium tartrate, potassium tartrate, lithium tartrate, rubidium tartrate, and caesium tartrate.

In some embodiments, the steel slag compositions comprising steel slag and an amine further comprise an inorganic compound. In some embodiments, the inorganic compound is selected from the group consisting of an alkali metal carbonate, an alkaline earth metal carbonate, an alkali metal sulphate, an alkaline earth metal sulphate, and combinations thereof. An alkali metal carbonate included in some embodiments of the steel slag compositions is selected from sodium carbonate, potassium carbonate, lithium carbonate, rubidium carbonate, caesium carbonate or a combination thereof. An alkaline earth metal carbonate included in some embodiments of the steel slag compositions is selected from calcium carbonate, beryllium carbonate, magnesium carbonate, strontium carbonate, barium carbonate, or a combination thereof. An alkali metal sulphate included in some embodiments of the steel slag compositions is selected from sodium sulphate, potassium sulphate, lithium sulphate, rubidium sulphate, caesium sulphate, or a combination thereof. An alkaline earth metal sulphate included in some embodiments of the steel slag compositions is selected from beryllium sulphate, magnesium sulphate, calcium sulphate, strontium sulphate, barium sulphate, or a combination thereof. In some embodiments, the inorganic compound included in some embodiments of the steel slag compositions is selected from calcium carbonate, sodium sulphate, sodium carbonate, potassium carbonate, lithium carbonate, calcium sulphate, potassium sulphate, lithium sulphate, or a combination thereof. In some embodiments, calcium carbonate is added to the steel slag compositions in the form of limestone. In some embodiments of compositions comprising steel slag, an amine, and an inorganic compound; the steel slag has a particle size of about 2 microns to about 45 microns. In some embodiments, the compositions comprise steel slag, an amine, and an inorganic compound selected from limestone, sodium sulphate or a combination thereof; wherein the steel slag has a particle size of about 2 microns to about 45 microns. In some embodiments, the compositions comprise steel slag, an amine selected from TIPA, TEA or a combination thereof, and an inorganic compound selected from limestone, sodium sulphate or a combination thereof; wherein the steel slag has a particle size of about 2 microns to about 45 microns.

In some embodiments, the inorganic compound is present in the steel slag compositions in an amount of about 0.1% to about 30% by weight of the composition, including values and ranges therebetween. In some embodiments, the inorganic compound is present in the steel slag compositions in an amount of about 0.1% to about 25%, about 0.1% to about 20%, about 0.1% to about 15%, or about 0.1% to about 10%, by weight of the composition, including values and ranges therebetween. In some embodiments, the inorganic compound is present in the steel slag compositions in an amount of about 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, or about 9%, including values therebetween, by weight of the composition. In some embodiments, the inorganic compound is present in the steel slag compositions in an amount of about 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, or about 30%, including values therebetween, by weight of the composition. In some embodiments, the inorganic compound is present in the steel slag composition in an amount of about 10% by weight of the composition. In some embodiments, the inorganic compound is present in the steel slag compositions in an amount of about 12% by weight of the composition. In some embodiments, the inorganic compound is present in the steel slag compositions in an amount of about 30% by weight of the composition.

In some embodiments of the compositions comprising steel slag, an amine, and an inorganic compound, the steel slag is present in an amount of about 69% to about 99% by weight of the composition, including values and ranges therebetween. In some embodiments of the compositions comprising steel slag, an amine, and an inorganic compound, the steel slag is present in an amount of about 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or about 99%, including values therebetween, by weight of the composition.

By the term “including values therebetween”, it will be understood by a person of ordinary skill in the art that to make the total percentage weight of the composition to 100%, the amount of the inorganic compound or the amount of steel slag can be adjusted to a first or second decimal points. For example, in a steel slag composition comprising about 0.1% amine, the amount of the inorganic compound or the amount of steel slag can be adjusted to a first decimal point, i.e. X%±0.1. For example, in a steel slag composition comprising about 90% steel slag, 0.1% amine, the amount of the inorganic compound can be adjusted to a first decimal point, i.e. to 9.9% instead of 10%. In another exemplary embodiment, in a steel slag composition comprising about 0.1% amine and about 10% inorganic compound, the amount of the steel slag can be adjusted to a first decimal point, i.e. to 89.9% instead of 90%. Thus, the term “including values therebetween” covers values ± 0.5 from X%. For example, in some embodiments, about 10% encompasses 9.5%, 9.6%, 9.7%, 9.8%, 9.9%, 10%, 10.1%, 10.2%, 10.3%, 10.4%, and 10.5%. In another exemplary embodiment, in a steel slag composition comprising about 0.7% amine, the amount of the inorganic compound or the amount of steel slag can be adjusted to X%±0.3, e.g., 9.3%, 11.3%, 12.3%, 29.3%, 87.3%, 69.3%, and the like.

If the amount of the amine is about 0.05%, 0.06%, 0.07%, 0.08%, or 0.09%, the amount of the inorganic compound or the amount of steel slag can be adjusted to a second decimal point. For example, in a composition comprising about 0.05% amine and 90% steel slag, the amount of the inorganic compound can be adjusted to 9.95% instead of 10%. Alternatively, the amount of the steel slag can be adjusted to 89.95% instead of 90%, i.e., the composition will comprise about 89.95% steel slag, 10% inorganic compound, and 0.05% amine. Such minor adjustments to the weight percentages of steel slag and the inorganic compounds can be easily envisaged by a person of ordinary skill in the art and are encompassed by the present disclosure.

In some embodiments, the steel slag compositions comprise steel slag in an amount of about 69% to about 99.85%, the amine in an amount of about 0.05% to about 1%, and the inorganic compound in an amount of about 0.1% to about 30%, including values and ranges therebetween, by weight of the composition. In some embodiments, the steel slag compositions comprise about 70% to about 90% steel slag, about 9.3% to about 29.9% inorganic compound, and about 0.1% to about 0.7% amine. In some embodiments, the steel slag compositions comprise about 69.3% to about 89.3% steel slag, about 10% to about 30% inorganic compound, and about 0.1%-0.7% amine. In some embodiments, the steel slag composition comprises about 90% steel slag, about 9.9% limestone, and about 0.1% amine. In some embodiments, the steel slag composition comprises about 70% steel slag, about 29.3% limestone, and about 0.7% amine. In some embodiments, the steel slag composition comprises about 87.3% steel slag, about 12% sodium sulphate, and about 0.7% amine. In some embodiments, the steel slag composition comprises about 89.9% steel slag, about 10% limestone, and about 0.1% amine. In some embodiments, the steel slag composition comprises about 69.3% steel slag, about 30% limestone, and about 0.7% amine. In some embodiments, the steel slag composition comprises about 88% steel slag, about 11.3% sodium sulphate, and about 0.7% amine. In various embodiments, the steel slag, the amine, and the inorganic compound can be combined in any of the amounts described herein to make the total weight of the composition to 100%.

As discussed above, it is hypothesized that the amine works as a chelating ligand by promoting surface dissolution of iron by complexation and/or weakening interatomic bonds in the vicinity of iron thereby facilitating its detachment. If an inorganic compound is added to the steel slag composition, the dissolved iron reacts with the added inorganic compounds such as carbonates and/or sulfates to form additional binding phases such as Fe-hemicarboaluminate and/or Fe-Ettringite as shown by the below equations:

4Ca2+ + 2Fe(OH)4- + 0.5CO32- + 5OH- + 3.5H2O? Ca4Fe2(CO3)0.5 (OH)12·3.5H2O (Fe- Hemicarboaluminate) - I

6Ca2+ + 2Fe(OH)4 - + 3SO42- + 4OH- + 26H2O ? Ca6Fe2(SO4)3(OH)12·26H2O (Fe-Ettringite) - II

The formation of additional binding phases is evident from the peaks in Figure 7 and is responsible for the increase in the compressive strength observed when compared with unmodified LD slag, i.e., steel slag in the absence of the amine and/or the inorganic compound.

The present disclosure also provides methods for making the steel slag compositions. Figure 1 shows a broad overview of steps from obtaining steel slag, preparing steel slag compositions, and conducting field trials. Figure 2 shows an exemplary flow chart of the process for preparing a steel slag composition according to some embodiments of the present disclosure.

In some embodiments, the steel slag composition is prepared by mixing steel slag and an amine.

In some embodiments, a method for preparing the steel slag composition comprises mixing steel slag and an amine and grinding this mixture to a desired particle size. In some embodiments, the mixture comprising the steel slag and the amine is ground to a particle size of about 2 microns to about 45 microns. In some embodiments, the ground mixture is passed through a 45-micron sieve until retention on screen (ROS) is equal to or less than 15%.

In some embodiments, a method for preparing the steel slag composition comprises grinding steel slag to a desired particle size, e.g., about 2 microns to about 45 microns, and mixing the ground steel slag with an amine. In some embodiments, prior to mixing with the amine, the ground steel slag is passed through a 45-micron sieve until retention on screen is equal to or less than 15%. In some embodiments, the ground steel slag is first mixed with the amine and then this mixture is passed through a 45-micron sieve until retention on screen is equal to or less than 15%.

In some embodiments of the methods described above, the steel slag is added in an amount of about 99% to about 99.95% by weight of the composition and the amine is added in an amount of about 0.05% to about 1% by weight of the composition.

In some embodiments, an inorganic compound is added to the steel slag compositions. Accordingly, in some embodiments, a method for preparing a steel slag composition comprises mixing steel slag, an amine, and the inorganic compound. In some other embodiments, a method for preparing a steel slag composition comprises mixing steel slag, an amine, and the inorganic compound, and grinding this mixture to a desired particle size such as about 2 microns to about 45 microns. In some embodiments, this ground mixture is passed through a 45-micron sieve until retention on screen (ROS) is equal to or less than 15%. In some embodiments of the methods, the steel slag is added in an amount of about 69% to about 99.85% by weight of the composition, the amine is added in the amount of 0.05% to about 1% by weight of the composition, and the inorganic compound is added in an amount of about 0.1% to about 30% by weight of the composition.

In some embodiments, the amine employed in the above methods is an organic amine. In some embodiments, the organic amine is an alkanol amine including monoalkanol amine, dialkanol amine, and trialkanol amine. In some embodiments, the amine is selected from the group consisting of triethanol amine (TEA), triisopropanol amine (TIPA), monoethanol amine, diethanol amine, monoisopropanol amine, diisopropanol amine, diethanol isopropanol amine and combinations thereof.

In some embodiments, the inorganic compound employed in the above methods is selected from the group consisting of an alkali metal carbonate, an alkaline earth metal carbonate, an alkali metal sulphate, an alkaline earth metal sulphate, and combinations thereof. In some embodiments, the inorganic compound employed in the above methods is selected from the group consisting of calcium carbonate, sodium sulphate, sodium carbonate and combinations thereof.

Also provided herein is use of steel slag compositions of the disclosure in construction materials. Accordingly, in some embodiments, provided herein is a construction material comprising any of the steel slag compositions described herein. Construction materials comprising the steel slag compositions of the present disclosure include, but are not limited to, concrete, cement, and mortar.

In some embodiments, provided herein is a concrete composition comprising any of the steel slag compositions of the present disclosure. In some embodiments, the concrete composition comprises cement, sand, coarse aggregates, and a steel slag composition of the present disclosure. In some embodiments, the concrete composition comprises cement, sand, coarse aggregates, a steel slag composition of the present disclosure, and additional components including, but not limited to, fly ash, ground granulated blast furnace slag (GGBFS), metakaolin, and the like.

In some embodiments, the concrete composition comprises about 8% to about 13% cement and about 4% to about 6% of any of the steel slag compositions of the present disclosure. In some embodiments, the concrete composition comprises about 12.6% cement and about 4.2% of any of the steel slag compositions of the present disclosure. In some embodiments, the concrete composition comprises about 12.6% cement, about 4.2% of any of the steel slag compositions of the present disclosure, about 29.4% sand, and about 53.73% of aggregates. In some embodiments, the concrete composition comprises about 10.9% cement and about 5.9% of any of the steel slag compositions of the present disclosure. In some embodiments, the concrete composition comprises about 10.9% cement, about 5.9% of any of the steel slag compositions of the present disclosure, about 29.4% sand, and about 53.73% of aggregates. In some embodiments, the concrete composition comprises about 8.4% cement and about 4.2% of any of the steel slag compositions of the present disclosure. In some embodiments, the concrete composition comprises about 8.4% cement, about 4.2% of any of the steel slag compositions of the present disclosure, about 4.2% of GGBFS, about 29.4% sand, and about 53.73% of aggregates. In some embodiments, the concrete composition comprises about 9.85% cement, about 0.985% of any of the steel slag compositions of the present disclosure, about 9% of GGBFS, about 34.2% sand, and about 45.9% of aggregates.

In some embodiments, provided herein are cement compositions comprising any of the steel slag compositions of the present disclosure. In some embodiments, the cement composition comprises about 50% to about 80% cement and about 35% to about 20% of any of the steel slag compositions of the present disclosure. In some embodiments, the cement composition comprises about 65% cement and about 35% of any of the steel slag compositions of the present disclosure. In some embodiments, the cement composition comprises about 70% cement and about 30% of any of the steel slag composition of the present disclosure. In some embodiments, the cement composition comprises about 75% cement and about 25% of any of the steel slag composition of the present disclosure. In some embodiments, the cement composition comprises about 50% cement, about 25% GGBFS, and about 25% of any of the steel slag composition of the present disclosure. In some embodiments, the cement composition comprises about 50% cement, about 45% GGBFS, and about 5% of any of the steel slag compositions of the present disclosure.

In some embodiments, provided herein are cement compositions comprising clinker, the steel slag composition of the present disclosure, and optionally additional components including, but not limited to, blast furnace slag, gypsum, and the like. In some embodiments, the cement composition comprises about 0.5% to about 1% by weight of any of the steel slag compositions of the present disclosure. In some embodiments, a cement composition comprises about 40% to about 50% clinker, about 59.5% to about 49.5% blast furnace slag and about 0.5% to about 1% by weight of any of the steel slag compositions of the present disclosure. In an exemplary embodiment, a cement composition comprises about 45.5% clinker, about 50% blast furnace slag and about 0.5% of any of the steel slag compositions of the present disclosure.

The compositions, methods, and construction materials disclosed herein provide many advantages. First, the compositions of the present disclosure provide efficient utilization of steel making by-products and provide low-cost additives for construction materials. The steel slag compositions of the present disclosure serve as better additives for construction materials as these compositions improve strength of the construction material compared to conventionally used additives such as ground-granulated blast furnace slag, fly ash, metakaolin, clinker, and the like. As steel slag compositions of the present disclosure can be employed as replacement of cement in concrete compositions or as replacement of clinker in cement compositions, the compositions of the present disclosure can reduce greenhouse gases and/or carbon dioxide emissions. Thus, steel slag compositions of the present disclosure provide environment-friendly additives for construction materials.

It is to be understood that the foregoing descriptive matter is illustrative of the disclosure and not a limitation. While considerable emphasis has been placed herein on the particular features of this disclosure, it will be appreciated that various modifications can be made, and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. Those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein. Similarly, additional embodiments and features of the present disclosure will be apparent to one of ordinary skill in art based upon description provided herein.

Descriptions of well-known/conventional methods/steps and techniques are omitted so as to not unnecessarily obscure the embodiments herein. Further, the disclosure herein provides for examples illustrating the above described embodiments, and in order to illustrate the embodiments of the present disclosure certain aspects have been employed. The examples used herein for such illustration are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the following examples should not be construed as limiting the scope of the embodiments herein.

EXAMPLES
Throughout the Example section, the term “LD slag” is used and refers to the steel slag or a composition comprising the steel slag. Based on the context, it would be clear to one of ordinary skill in the art whether the term refers to the steel slag or a composition comprising the steel slag.

Example 1: Steel Slag Compositions, Concrete Products, Preparation and Properties
LD slag non-metallic generated from metal recovery plant of Industrial By-products Management Division (IBMD) of Tata Steel Ltd. was used as a raw material in this study. The particle size for this fraction typically is at a size range of 0-6 mm. Other materials used were fly ash, ground granulated blast furnace slag (GGBFS), metakaolin, limestone and ordinary Portland cement (OPC). The detailed granulometry and chemical analysis of all these raw materials is presented below:
Table 1. Physical and chemical properties of raw LD slag
Particle Size Distribution Chemical Element Percentage
Sieve Size (mm) % Passing SiO2 4.4%
4.75mm 96.9% Al2O3 7.8%
2.36mm 81.3% Fe2O3 18.3%
1.18mm 62.5% CaO 44.7%
0.60mm 50.2% MgO 5.4%
0.30mm 33.7% SO3 0.4%
0.15mm 4.6% Insoluble Residue 1.5%

Table 2: Physical and chemical properties of Fly Ash
Physical Properties: ROS, 45 µm = 22.0%
Chemical analysis
Chemical Element Percentage
LOI 4.26%
SiO2 56.61%
Al2O3 27.54%
Fe2O3 4.80%
CaO 5.00%
MgO 0.60%
SO3 0.40%
Insoluble Residue 72.00%
ROS: Retention on screen

Table 3: Physical and chemical properties of GGBFS
Physical Properties: ROS, 45µm = 6.0%
Chemical Properties
Chemical Element Percentage
LOI 1.1%
SiO2 33.2%
Al2O3 21.9%
Fe2O3 0.5%
CaO 35.0%
MgO 5.8%
SO3 0.10%
Insoluble Residue 1.22%
ROS: Retention on screen
Table 4: Physical and chemical properties of Metakaolin
Physical Properties: D(50) = 5.1µm
Chemical Properties
Chemical Element Percentage
LOI 0.9%
SiO2 50.2%
Al2O3 47.16%
Fe2O3 0.40%
CaO 0.00%
MgO 0.30%
SO3 0.00%
Insoluble Residue 81.00%

Table 5. Chemical Composition of Limestone
Component Weight percentage
SiO2 14.66
Al2O3 2.76
Fe2O3 1.3
CaO 45.0
MgO 0.4
LOI 35.6
LOI = Loss on Ignition
For sample IDs, LD0G3 and LD0G4, steel slag was grounded with the amine from Table 7, , to cement fineness, i.e. material retained on 45µm sieve equal to 15%. For sample IDs, LDS1G3 and LDS1G4, steel slag was inter-ground with 10% limestone and the amine from Table 7, , to cement fineness, i.e. material retained on 45µm sieve equal to 15%. The product of physical and chemical modifications of LD slag was tried in concrete grade of M30 and compared with concrete containing locally available Fly Ash and GGBFS, the conformity of concrete was as per IS 456: 2000 (RA2016), the details of the physical and chemical modification of LD Slag are summarized in the following tables:
Table 6. Inorganic Chemical Modification Details
Sample ID Chemical modification
LD0 As it is ground slag (without any chemical modification)
LDS1 90% LD Slag + 9.9% Limestone

Table 7. Organic Chemical Modification Details
ID Triethanol amine (TEA) Tri isopropanol amine (TIPA)
G3 0.05% 0.05%
G4 0% 0.1%

An examination of cold compressive strength of concrete comprising the four compositions - LD0(G3), LD0(G4), LDS1(G3) and LDS1(G4) showed that results were consistent. Grinding times and retention on 45 µm are given in Table 8. It can be seen from Table 8 that by chemically modifying the LD slag, the retention on screen (ROS) on 45 µm also decreases which indicates that chemical modification of LD slag described herein makes grinding of LD slag easier.
Table 8. Grinding Trials (Sample Size = 6 kg., Grinding time = 4 hours)

Sample ID Retention on 45µm
LD0 28%
LD0(G3) 16%
LD0(G4) 15%
LDS1(G3) 10%
LDS1(G4) 14%
GGBFS 10%

Experimental Results (Cold Compressive Strength, CCS):
a) Experimental results of ground and activated LD slag for M30 grade concrete with 25% replacement to fly ash
The results of compositions developed from ground LD slag and activated by an amine or a combination of an amine and an inorganic compound are discussed in this section. Table 9 shows details of concrete compositions comprising steel slag compositions of the present disclosure and a concrete composition comprising conventional components. Table 9 also shows cold compressive strength (CCS) values for these concrete compositions at the bottom. These CCS values are represented graphically in Figure 3.

? Table 9 contains the design mix and results of M30 grade concrete (25% replacement):
o Comparison: 75% OPC + 25% Fly Ash v/s 75% OPC + 25% LD0 v/s 75% OPC + 25% LD0(G3) v/s 75% OPC + 25% LD0(G4) v/s 75% OPC + 25% LDS1(G3) v/s 75% OPC + 25% LDS1(G4).
? Cement used: OPC Brand (ACC OPC 53)
? Target Strength = 30 (fck) + 1.65 (t) x 5 (Assume standard deviation) = 38.3 N/mm2 - IS 456 : 2000 (RA 2006) for both cases
? The column showing a concrete composition comprising 75% OPC and 25% fly ash is the standard/conventional mix design. The concrete composition 75% OPC + 25% LD0 comprises OPC at 75% and ground steel slag without any chemical modification (LD0) at 25%. The remaining columns show concrete compositions according to the present disclosure. In 75% OPC + 25% LD0 composition and the concrete compositions according to the present disclosure, the percent replacement by LD slag is 25% and the replacement is for fly ash.

Table 9. Design mix and Cold Compressive Strength (CCS) Comparison results for M30 grade concrete (25% Fly ash replacement with LD slag)
Item Description 75% OPC + 25% Fly ash 75% OPC +25% LD0 75% OPC+ 25%LD0 (G3) 75% OPC+ 25%LD0(G4) 75% OPC + 25% LDS1(G3) 75% OPC + LDS1(G4)
OPC (Kg/m3) 277.5 277.5 277.5 277.5 277.5 277.5
Fly Ash (Kg/m3) 92.5 0 0 0 0 0
LD0 (Kg/m3) 0 92.5 0 0 0 0
LD0(G3) (Kg/m3) 0 0 92.5 0 0 0
LD0(G4) (Kg/m3) 0 0 0 92.5 0 0
LDS1(G3) (Kg/m3) 0 0 0 0 92.5 0
LDS1(G4) (Kg/m3) 0 0 0 0 0 92.5
Sand (Kg/m3) 646 646 646 646 646 646
Aggregates (Kg/m3) 1180 1180 1180 1180 1180 1180
w/c ratio 0.41 0.42 0.42 0.42 0.42 0.42
Admixture % BWOC 0.6 0.6 0.6 0.6 0.6 0.6
Slump @ 30 min. 145 110 110 120 110 120
Compressive Strength (Mpa)
1 Day 11.9 9.09 8.9 10.2 14 12.1
3 Days 22.4 14.53 24.3 22.7 27.6 26.9
7 Days 32.4 23.82 31.7 31.1 35.8 35.8
28 Days 44.6 37.36 49 49 47.9 50.2

From Table 9, it can be seen that by chemically modifying the LD slag, 28 day strengths are higher than fly ash mix and unmodified LD slag (LD0) mix.

The CCS results @ 25% replacement of LD Slag clearly indicate that the activated LD slag products shows higher values/strength. The standard mix CCS strength was 44.6 after 28 days where the values of the activated LD slag (LD0G3, LD0G4, LDS1G3, and LDS1G4) with 25% replacement values are between 47.9 Mpa to 50.2 Mpa. Said results also highlight the importance of amine and the optional inorganic compound modification to LD slag. Particularly, the compositions comprising activated LD slag (activation of LD slag with amine and optionally an inorganic compound) shows improved strength compared to compositions comprising unmodified LD slag.
b) Experimental results of ground and activated LD slag for M30 grade concrete with 35% replacement to fly ash
The results of compositions developed from ground LD slag and activated by an amine or a combination of an amine and an inorganic compound are discussed in this section. Table 10 shows details of concrete compositions comprising steel slag compositions of the present disclosure and a concrete composition comprising conventional components. Table 10 also shows cold compressive strength (CCS) values for these concrete compositions at the bottom. These CCS values are represented graphically in Figure 4.

? Table 10 contains the design mix and results of M30 grade concrete (35% replacement):
o Comparison :65% OPC + 35% Fly Ash v/s 65% OPC + 35% LD0(G3) v/s 65% OPC + 35% LD0(G4) v/s 65% OPC + 35% LDS1(G3) v/s 65% OPC + 35% LDS1(G4).
? Cement used: OPC Brand (ACC OPC 53)
? Target Strength = 30 (fck) + 1.65 (t) x 5 (Assume standard deviation) = 38.3 N/mm2 - IS 456 : 2000 (RA 2006) for both cases
• The column showing a concrete composition comprising 65% OPC and 35% fly ash is the standard/conventional mix design whereas the remaining columns are the newly developed materials (compositions according to the present disclosure). Here the replacement of the percent of LD slag is 35% and the substitution is for fly ash.

Table 10. Design mix and Cold Compressive Strength (CCS) Comparison results for M30 grade concrete (35% Flyash replacement with LD slag replacement)
Item Description 65% OPC + 35% Fly ash 65% OPC+ 35% LD0 (G3) 65% OPC+ 35% LD0(G4) 65%OPC + 35% LDS1(G3) 65% OPC + 35% LDS1(G4)
OPC (Kg/m3) 240.5 240.5 240.5 240.5 240.5
Fly Ash (Kg/m3) 129.5 0 0 0 0
LD0(G3) (Kg/m3) 0 129.5 0 0 0
LD0(G4) (Kg/m3) 0 0 129.5 0 0
LDS1(G3) (Kg/m3) 0 0 0 129.5 0
LDS1(G4) (Kg/m3) 0 0 0 0 129.5
Sand (Kg/m3) 646 646 646 646 646
Aggregates (Kg/m3) 1180 1180 1180 1180 1180
w/c ratio 0.42 0.42 0.42 0.42 0.42
Admixture % BWOC 0.6 0.6 0.6 0.6 0.6
Slump @ 30 min. 160 100 100 100 100
Compressive Strength (Mpa)
1 Day 14.3 10.7 11 15.4 12.9
3 Days 23.8 27 25.4 25.7 24.8
7 Days 29.4 35.1 34.1 32.3 32.3
28 Days 41.4 43.3 41.5 42.1 42.1

The CCS results @ 35% replacement of LD Slag clearly indicate that the activated LD slag products of the present disclosure show higher values. The standard mix CCS strength was 41.4 Mpa after 28 days where the values of the LD slag with 35% replacement values are between 41.5 to 43.3 Mpa.

From Table 10, it can also be seen that the chemically modified LD slag can be replaced up to a level of 35% without affecting the strength.
c) Experimental results of ground and activated LD slag for M30 grade concrete with 25% replacement to GGBFS
The results of compositions developed from ground LD slag and activated by an amine or a combination of an amine and an inorganic compound are discussed in this section. Table 11 shows details of concrete compositions comprising steel slag compositions of the present disclosure and a concrete composition comprising conventional components. Table 11 also shows cold compressive strength (CCS) values for these concrete compositions at the bottom. These CCS values are represented graphically in Figure 5.

? Table 11 contains the design mix and results of M30 grade concrete (25% replacement):
? Comparison: 50% OPC + 50% GGBS v/s 50% OPC + 25% GGBS + 25% LD0(G3) v/s 50% OPC +25% GGBS + 25% LDS1(G4), OPC Brand = Dalmia OPC 53) Cement used: OPC Brand (ACC OPC 53)
• Target Strength = 30 (fck) + 1.65 (t) x 5 (Assume standard deviation) = 38.3 N/mm2 - IS 456 : 2000 (RA 2006)
• The column showing a concrete composition comprising 50% OPC and 50% GGBS is the standard mix design. The concrete composition 50% OPC + 25% GGBS + 25% LD0 comprises OPC at 50%, GGBS at 25% and ground steel slag without any chemical modification (LD0) at 25%. The remaining columns show the newly developed materials according to the present disclosure. In 50% OPC + 25% GGBS + 25% LD0 and the newly developed materials, the replacement of the percent of LD slag is 25% and the substitution is for GGBFS.
Table 11. Design mix and Cold Compressive Strength (CCS) Comparison results for M30 grade concrete (25% GGBFS replacement with LD slag)
Item Description 50% OPC + 50% GGBS 50% OPC + 25% GGBS + 25% LD0 50% OPC + 25% GGBS + 25% LDS1(G4)
OPC (Kg/m3) 185 185 185
GGBS (Kg/m3) 185 92.5 92.5
LD0 0 92.5 0
LDS1(G4) (Kg/m3) 0 0 92.5
Sand (Kg/m3) 646 646 646
Aggregates (Kg/m3) 1180 1180 1180
w/c ratio 0.41 0.41 0.44
Admixture % BWOC 0.6 0.6 0.6
Slump @ 30 min. 130 110 115
Compressive Strength (N/mm2)
1 Day 19.4 14.74 17.1
3 Days 33.1 23.7 32.1
7 Days 40.3 30.97 41.9
28 Days 50.2 41.51 51.6

From Table 11, it can be observed that 25% of GGBFS can be replaced with chemically modified LD Slag without affecting the final strength. Said results also highlight the importance of amine and the optional inorganic compound modification to LD slag. Particularly, the compositions comprising activated LD slag (activation of LD slag with amine and optionally an inorganic compound) shows improved strength compared to compositions comprising unmodified LD slag.
d) Experimental results of micronized LD and activated LD slag for M50 grade concrete with 5% replacement
The target fineness of the product was to grind/inter-grind (with chemical activators) to material retained on 45µm sieve less than 15%. In this study, micronizing of LD slag was also tried. The product of physical and chemical modifications of LD slag was tried in concrete grade of M50 and compared with concrete containing metakaolin (the conformity of concrete was as per IS 456: 2000 (RA2016)). The results of micronized LD slag (LDM) and micronized LD slag activated by chemical modification (LDMM) is presented in Table 12. Samples designated as LD2G10, LD2G11, LD2G12, and LD2G13 were ground/inter-ground to obtain a retention on 45µm sieve of less than 15%; but not jet milled to 3.9 µm as done for the micronized LD slag samples (LDM and LDMM).
Table 12. Physical and Chemical Modification of LD Slag
Sample ID In-organic Chemical Modification Organic Chemical Modification Physical Modification
(Inter-grinding in ball mill, sample size = 6 kg, time = 4 hours) Comments
LDM - - - Jet milled D(50) = 3.9 µm
Micronized LD Slag
LDMM 70% LDM + 29.3% Limestone 0.7% TEA ROS, 45 µm = 6% -
LD2G10 70% LD Slag + 29.3% Limestone 0.7% TEA ROS, 45 µm = 6% -
LD2G11 70% LD Slag + 29.3% Limestone 0.7% TIPA ROS, 45 µm = 2% -
LD2G12 87.3% LD Slag + 12% Sodium Sulfate 0.7% TEA ROS, 45 µm = 8% -
LD2G13 87.3% LD Slag + 12% Sodium Sulfate 0.7% TIPA ROS, 45 µm = 6% -
ROS – retention on screen
The detailed mix design of newly developed product with the standard mix design is presented in Table 13 and the comparative result is presented in Figure 6.
? Table 13 contains the design mix and experimental Results (Grade of Concrete = M50, 50% OPC + 45% GGBS + 5% Metakaolin v/s 50% OPC + 45% GGBS + 5% LD Slag Modifications, OPC Brand = ACC OPC 53)
? Target Strength = 50(fck) + 1.65 (t) x 5 (Assume standard deviation) = 58.3 N/mm2 - IS 456: 2000 (RA 2006).

Table 13. Design mix and Cold Compressive Strength (CCS) Comparison results
for M50 grade concrete (5% Metakaolin replacement with LD slag activated and micronized)
Item Description 50% OPC +45%GGBS +5%Metakaolin 50% OPC+ 45%
GGBS +5% LDM 50% OPC
+ 45%GGBS +5% LDMM 50% OPC
+ 45%GGBS +5%LD2G10 50% OPC
+ 45%GGBS +5%LD2G11 50% OPC
+ 45%GGBS +5%LD2G12 50% OPC
+ 45%GGBS +5%LD2G13
OPC (Kg/m3) 225 225 225 225 225 225 225
GGBS (Kg/m3) 205.5 205.5 205.5 205.5 205.5 205.5 205.5
Metakaolin (Kg/m3) 22.5 0 0 0 0 0 0
LDM(Kg/m3) 0 22.5 0 0 0 0
LDMM(Kg/m3) 0 22.5 0 0 0 0
LD2G10 0 0 0 22.5 0 0 0
LD2G11 0 0 0 0 22.5 0 0
LD2G12 0 0 0 0 0 22.5 0
LD2G13 0 0 0 0 0 0 22.5
Sand (Kg/m3) 782 782 782 782 782 782 782
Aggregates (Kg/m3) 1049 1049 1049 1049 1049 1049 1049
w/c ratio 0.33 0.35 0.35 0.35 0.35 0.35 0.35
Admixture % BWOC 0.6 0.6 0.6 0.6 0.6 0.6 0.6
Slump @ 30 min. 95 125 125 110 100 110 100
Compressive Strength (Mpa)
1 Day 13.6 12.7 12.4 12.8 12.2 15.2 17.4
3 Days 29.9 31.4 34.8 33.9 34.2 36 34
7 Days 39.4 45.8 47 47.2 47.9 44.4 43.1
28 Days 54.9 57.9 59.5 61.9 61.8 56.8 56.8

From Table 13, it can be seen that LD slag (modified or micronized unmodified) provides better results than metakaolin when used in high grade concretes. It can also be seen that chemically modified LD slag (LDMM, LD2G10, LD2G11) strengths were substantially better than unmodified micronized LD slag (LDM).
The CCS results @ 5% replacement of Metakaolin with Micronized and Chemically modified LD Slag clearly indicate that the newly developed products have higher CCS values. It can be observed from Table 13 and Figure 6 that the standard mix CCS strength is 54.9 Mpa after 28 days whereas the values of the Micronized and Chemically modified LD slag with 5% replacement of Metakaolin values are between 56.8 to 61.9 Mpa.
Example 2: Cement Compositions
Three samples were prepared as follows:
Sample 1: Composition containing LD slag without chemical modification
OPC – 70%
Ground LD slag – 30%
Water cement ratio – 0.4%

Sample 2: Composition containing chemically modified LD slag
OPC – 70%
Ground LD slag – 29.1%
Limestone – 0.9%
TIPA – 0.03%
Water cement ratio – 0.4%

Sample 3: Composition containing chemically modified LD slag
OPC – 70%
Ground LD slag – 29.5%
Sodium sulphate – 0.5%
TIPA – 0.03%
Water cement ratio – 0.4%

The samples were subjected to X-ray diffraction (XRD) studies. Figure 7 shows a comparative XRD data confirming the reactivity and presence of peaks of C3S (Tricalcium Silicate) and C2S (Dicalcium Silicate) for samples containing ground LD slag and activated LD slag.

From Figure 7, it can be seen that additional peaks are formed around 2 theta angle of 9 and 11 because of the chemical activation of the LD slag which contributes to an increase in performance of the LD slag.

Tables 14-16 show the XRD peaks for the above three samples.
Table 14: Peak List of Sample 1 (Unmodified LD Slag)
Table 15: Peak List of Sample 2 (Modified LD Slag)
Table 16. Peak list of Sample 3 (Modified LD Slag)
Example 3: Cement trials
3 Kgs of following compositions were ground in a ball mill for two and half hours and tested for its parameters like setting time and compressive strength. LD slag was ground separately along with sodium sulphate and TEA as chemical activators: 35 kgs of LD Slag (0-6 mm), 15 Kgs of Sodium Sulfate and 1.5 liters of triethanol amine (TEA) was ground in ball mill for 3 hours and the retention on 45 microns was found to be 15%.
Table 17. Cement Trials using Modified LD slag
Components Trial A Trial B
Clinker (wt %) 50 45.5
Blast Furnace Slag (wt %) 46 50
Gypsum (wt %) 4 4
Modified LD Slag (wt %) 0 0.5
Sp. Surface area 332 353
Retention on 45 microns 18.6 18.8
IST (Minutes) 120 100
FST (Minutes) 195 180
Compressive Strength (Mpa)
1 Day 15.4 16.9
3 Days 34.5 35.2
7 Days 46.2 46.2
28 Days 59.5 59.1

As can be seen from Trial B, with 0.5% addition of modified LD slag, an additional 4% of blast furnace slag could be loaded in the cement composition without affecting the strength.

Example 4: Additional Compositions
Additional compositions comprising LD slag, an amine, and an inorganic compound were prepared as follows. The target fineness of the product was to grind/inter-grind (with chemical activators) to cement fineness i.e. material retained on 45µm sieve equal to 15%.
Table 18. Inorganic Chemical Modification Details
Sample ID Chemical modification
LD3A3 96.8% LD Slag + 3.2% Sodium Sulfate
LD3(A3A) 98.0% LD Slag + 2.0% Sodium Sulfate
LDS1A3 90.0% LD Slag + 8.0% Limestone + 2.0% Sodium Sulfate
LDS1(A3-B) 90.0% LD Slag + 9.0% Limestone + 1.0% Sodium Sulfate
LD3(A26B) 99.0% LD Slag + 1.0% Sodium Carbonate

Samples from Table 18 were further modified using organic compounds as shown in Table 19 to prepare final formulations as LD3A3G1, LD3A3G2, LD3A3G3, LD3A3G4, LD3(A3A)G1, LD3(A3A)G2, LD3(A3A)G3, LD3(A3A)G4, LDS1A3G1, LDS1A3G2, LDS1A3G3, LDS1A3G4, LDS1(A3-B)G1, LDS1(A3-B)G2, LDS1(A3-B)G3, LDS1(A3-B)G4, LD3(A26B)G1, LD3(A26B)G2, LD3(A26B)G3, and LD3(A26B)G4.
Table 19. Organic Chemical Modification Details
ID Glycerol Triethanol amine Tri isopropanol amine
G1 0.05% 0.05% 0%
G2 0% 0.05% 0%
G3 0% 0.05% 0.05%
G4 0% 0% 0.1%

INCORPORATION BY REFERENCE
All references, articles, publications, patents, patent publications, and patent applications cited herein are incorporated by reference in their entireties for all purposes. However, mention of any reference, article, publication, patent, patent publication, and patent application cited herein is not, and should not be taken as, an acknowledgment or any form of suggestion that they constitute valid prior art or form part of the common general knowledge in any country in the world.

Claims:We Claim:

1. A steel slag composition for use in a construction material, comprising steel slag and an amine.
2. The steel slag composition as claimed in claim 1, wherein the steel slag has a particle size of about 2 microns to about 45 microns.
3. The steel slag composition as claimed in claim 1, wherein the amine is an organic amine.
4. The steel slag composition as claimed in claim 3, wherein the organic amine is an alkanol amine.
5. The steel slag composition as claimed in claim 4, wherein the alkanol amine is selected from the group consisting of triethanol amine (TEA), triisopropanol amine (TIPA), monoethanol amine, diethanol amine, monoisopropanol amine, diisopropanol amine, diethanol isopropanol amine and combinations thereof.
6. The steel slag composition as claimed in claim 1, wherein the amine is present in an amount of about 0.05% to about 1% by weight of the composition.
7. The steel slag composition as claimed in claim 1, wherein the steel slag is present in an amount of about 99% to about 99.95% by weight of the composition.
8. The steel slag composition as claimed in claim 1, wherein the composition comprises about 99.9% steel slag and about 0.1% amine.
9. The steel slag composition as claimed in claim 8, wherein the amine is triethanol amine, triisopropanol amine, or a combination thereof.
10. The steel slag composition as claimed in claim 8, wherein the amine comprises about 0.05% triethanol amine and about 0.05% triisopropanol amine.
11. The steel slag composition as claimed in claim 1, wherein the composition comprises an inorganic compound selected from the group consisting of an alkali metal carbonate, an alkaline earth metal carbonate, an alkali metal sulphate, an alkaline earth metal sulphate, and combinations thereof.
12. The steel slag composition as claimed in claim 11, wherein the inorganic compound is selected from the group consisting of sodium carbonate, calcium carbonate, potassium carbonate, lithium carbonate, calcium sulfate, sodium sulphate, potassium sulfate, lithium sulfate and combinations thereof.
13. The steel slag composition as claimed in claim 12, wherein the calcium carbonate is present in the form of limestone.
14. The steel slag composition as claimed in claim 11, wherein the steel slag is present in an amount of about 69% to about 99.85%, the amine is present in an amount of about 0.05% to about 1%, and the inorganic compound is present in an amount of about 0.1% to about 30%, by weight of the composition.
15. The steel slag composition as claimed in claim 14, wherein the composition comprises about 70% to about 90% steel slag, about 9.3% to about 29.9% inorganic compound, and about 0.1% to 0.7% amine.
16. The steel slag composition as claimed in claim 15, wherein the composition comprises about 90% steel slag; about 9.9% of an inorganic compound, wherein the inorganic compound is limestone; and about 0.1% amine.
17. The steel slag composition as claimed in claim 15, wherein the composition comprises about 70% steel slag; about 29.3% of an inorganic compound, wherein the inorganic compound is limestone; and about 0.7% amine.
18. The steel slag composition as claimed in claim 15, wherein the composition comprises about 87.3% steel slag; about 12% of an inorganic compound, wherein the inorganic compound is sodium sulphate; and about 0.7% amine.
19. A steel slag composition for use in a construction material, comprising steel slag, an organic amine, and an inorganic compound selected from the group consisting of an alkali metal carbonate, an alkaline earth metal carbonate, an alkali metal sulphate, an alkaline earth metal sulphate and combinations thereof.
20. The steel slag composition as claimed in claim 19, wherein the steel slag has a particle size of about 2 microns to about 45 microns.
21. The steel slag composition as claimed in claim 19, wherein the organic amine is selected from the group consisting of triethanol amine, triisopropanol amine, and a combination thereof.
22. The steel slag composition as claimed in claim 19, wherein the inorganic compound is selected from the group consisting of sodium carbonate, calcium carbonate, sodium sulphate, and a combination thereof.
23. The steel slag composition as claimed in claim 22, wherein the calcium carbonate is present in the form of limestone.
24. A construction material comprising the steel slag composition as claimed in any one of claims 1-23.
25. The construction material as claimed in claim 24, wherein the construction material is selected from the group consisting of concrete, cement, and mortar.
26. A method for preparing a steel slag composition as claimed in claim 1, the method comprising mixing the steel slag and the amine to obtain the composition.
27. The method as claimed in claim 26, the method comprising grinding the steel slag and the amine to a particle size of about 2 microns to about 45 microns
28. The method as claimed in claim 26, the method comprising grinding steel slag to a particle size of about 2 microns to about 45 microns, and mixing the steel slag with the amine to obtain the composition.
29. The method as claimed in claim 26 or 28, wherein the composition or the steel slag ground to a particle size of about 2 microns to about 45 microns is passed through a 45 micron sieve until retention on screen is equal to or less than 15%.
30. The method as claimed in any one of claims 26 to 29, wherein the steel slag is added in an amount of about 99% to about 99.95% by weight of the composition and the amine is added in an amount of about 0.05% to about 1% by weight of the composition.
31. The method as claimed in any one of claims 26 to 29, comprising adding an inorganic compound selected from the group consisting of an alkali metal carbonate, an alkaline earth metal carbonate, an alkali metal sulphate, an alkaline earth metal sulphate, and a combination thereof.
32. The method as claimed in claim 31, wherein the inorganic compound is selected from the group consisting of sodium carbonate, calcium carbonate, sodium sulphate, and a combination thereof.
33. The method as claimed in claim 31, wherein the steel slag is added in an amount of about 69% to about 99.85% by weight of the composition, the amine is added in the amount of 0.05% to about 1% by weight of the composition, and the inorganic compound is added in an amount of about 0.1% to about 30% by weight of the composition.