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The purpose of this study was to the low-temperature synthesis of cobalt-containing diopside pigments based on granulated blast furnace slag and to study the characteristics of the mineral formation processes, changes in the structure and colour indices.

Synthesis of cobalt-containing diopside pigments based was carried out by the directional formation of the mineralogical composition with the introduction of part of the components using granulated blast-furnace slag.

It has been established that the formation of the diopside phase in pigments containing blast-furnace slag as the main component proceeds at low temperatures (1,100°C–1,150 °C). The colour of diopside pigments is formed because of the isomorphic substitution of Si4+ ions for Al3+ ions and Mg2+ ions for Co2+ ions. It is expedient to add CoO in an amount of 0.9 mol (18 Wt.%) into the composition of diopside pigments based on blast-furnace slag to obtain defect-free violet glazes.

The developed diopside pigments enable obtaining of high-quality violet glazes for ceramics. The application of the obtained results can significantly reduce the consumption of traditional raw materials in the composition of silicate ceramic pigments, as well as reduce their firing temperature.

Calcium, magnesium and silicon oxides are the main components of blast-furnace slag. In addition, granulated blast furnace slag is mainly represented by the glassy phase, which determines its high activity during the firing process. These factors are prerequisites for using the blast-furnace slag as a valuable substitute for chemically pure or natural raw materials in silicate pigments and reducing their firing temperature.

The purpose of this paper is to study the fertility potential of the iron- and steel-making process waste granulated blast furnace slag to recover it as a beneficial product.

This slag fertilizer was mixed with organic fertilizer to enrich and dung the vegetable sets are pepper, lettuce and cucumbers.

In this study, 100 per cent granulated slag, 75 per cent granulated slag + 25 per cent fermented manure, 50 per cent granulated slag + 50 per cent fermented manure and 25 per cent granulated slag + 75 per cent fermented manure compositions were mixed with water and added to seeding pots. The growth rate of vegetable sets and also the level of contamination of heavy metals such as lead, copper, aluminum, mercury and cadmium were analyzed. The analyses results showed that contamination rates of lead, copper, aluminum, mercury and cadmium in lettuce and cucumber samples were in the range of acceptable levels for human health. Slag fertilizer enforced the set of growth rate and productivity, too.

By the recovery of the waste slag storage, transport and annihilation economical load on the industry would be eliminated, waste recovery contributes to the economical gaining and beneficial recovered products replace the need of fertility products.

The purpose of this paper is to establish physical-chemical patterns and process parameters for obtaining low-temperature pink pigments with the structure of tin sphene using granulated blast-furnace slag.

Thermodynamic calculations were made in the work to assess the probability of malayaite phase formation during firing of slag-containing pigments. Mineralogical composition of synthesized pigments was evaluated by X-ray phase analysis. Spectral characteristics of pigments absorption in the infrared region were determined with the use of Fourier IR-spectrometry. Colour characteristics of the developed pigments and glass coatings with their introduction were studied on the comparator colour. Density of ceramic pigments was determined by pycnometric method, and chemical resistance was found on their weight loss after boiling in 1 N hydrochloric acid solution and 1 N sodium hydroxide solution.

Peculiar features of formation of the mineralogical composition of pink pigments are studied in the system CaO-MgO-Al₂O₃-SiO₂-SnO₂-Cr₂O₃ with the use of granulated blast-furnace slag. The end product and carrier of the pink colour is the solid solution on the basis of tin sphene. It is established that the most rational concentration of chromium (III) oxide for the formation of pink colouring of the pigments is 2 Wt.%.

The usage of developed pigments provides obtaining high-quality pink-coloured glaze coatings, in particular for ceramic tiles.

Activity of the components of blast-furnace slag in combination with the effective mineralizing action of B₂O₃ additive allows performing the firing of pink of the pigments with the formation of tin sphene at reduced temperature of 1,200°C.

This study investigates the effect of slag of blast furnace (SL) and sand of dune, (SD) replacement of cement on the durability of cement to chemical aggressive water (acid and sulfates) attack, Tow replacement levels were considered in the study: (5% sand of dune + 15% slag) and (10% sand of dune + 15% slag) by weigh to cement. The other parameters durability investigated in the study were: volumetric stability (shrinkage of drying and swelling), the concrete water permeability. The chemical resistance of cement to the acid and sulfate attack was evaluated by compressive strength reduction of cement specimens were immersed in 5% chloride magnesium and in 5% sodium sulfate solution for a total period of 28 and 90 days. the results obtained show that substitution partial of cement by slag and sand of dune to offer to cement a better stability to the chemical aggressive, and swelling however we noted that the increase in the content of sand of dune of 10% generates a slight increase in shrinkage of drying compared to cement without additions, the water permeability which is an essential characteristic of durability of concrete to be improved specially with partial replacement cement at (5% sand of dune + 15% slag) by weight cement.

This paper aims to present an experimental investigation on the performances of alkali-activated slag (AAS) concrete and Portland slag cement (PSC) concrete under the influence of elevated temperature. In the present study, the alkali-activated binder contains 85% of ground granulated blast furnace slag (GGBFS) and 15% of powder blended as chemical activators.

For the purpose, standard size of cube, cylinder and prism have been cast for a designed mix of concrete. The AAS concrete specimens were kept for water as well as air curing. After attaining the maturity of 28 days, the samples were first exposed to different elevated temperatures, i.e. 100°C, 200°C, 300°C, 400°C, 500°C, 600°C, 700°C and 800°C. Later on, the tests were conducted on these samples to find the change in weight and the residual strength of the concrete.

After 500°C exposure, a considerable amount of the strength loss has been observed for AAS concrete. It has been evaluated that the performance of AAS concrete is better than that of the PSC concrete at elevated temperature.

The present research work is being applied on the material for which the experimental result has been obtained.

The author has tried to develop a new type of binder by using steel industry waste material and then tested at elevated temperature to sustain at high temperatures.

This research may give a social impact for developing mass housing project with a lower cost than that of using a conventional binder, i.e. cement.

A new type of binder material is being developed.

This paper aims to express a mathematical model that predicts the effect of mineral additives on the physical–mechanical properties of high-performance sand concrete (HPSC), using SAS's JMP7 statistical analysis software.

A mixture design modeling approach is applied to sand concrete (SC) for optimizing mixtures without being obliged to do a lot of experiments, where the cement is partially replaced with two mineral additives silica fume (SF) and blast furnace slag (BFS) in proportions as high as 20% of the mass. A total of 15 mixtures of sand concrete is prepared in the laboratory using this analytical technique in combinations with binary and ternary systems to estimate the workability and the compressive strength (CS) of sand concrete at 7 and 28 days.

The results obtained showed that the use of derived models based on the experimental design approach greatly assisted in understanding the interactions between the various parameters of the studied mixtures; the mathematical models present excellent correlation coefficients (R² = 0.96 for CS7 days, R² = 0.93 for CS28 days and R² = 0.95 for slump) for all studied responses. Moreover, it was also found that the inclusion of additives (SF and BFS) in binary mixture SC12 and ternary mixtures SC8 leads to a significant improvement in mechanical strength compared to reference sand concrete SC15. These results give the possibility to obtain a formulation of HPSC.

This paper shows the possibility of manufacturing high-performance sand-concrete with good compressive strength; the developed mathematical model by using SAS's JMP7 statistical analysis software allowed us to reach a strength compression value of about 60 MPa, in 28 days, by replacing 10% of the cement weight with silica fume. Furthermore, with partial replacement of the cement weight (15%) with two additions such as silica fume (10%) and blast furnace slag (5%), a 58 MPa of compressive strength can be achieved, without overlooking the fact that this can be a key economic and environmental alternative.

This paper attempted to study the alkali-activated (AA) binder consisting of 94% of ground granulated blast furnace slag (GGBFS) and 6% of blended powder of alkali metal hydroxide and metal sulfate, which acted as an activator.

Several concrete specimens (cubes, cylinders and prisms), which were casted using AA binders, were further tested for mechanical properties after exposure to elevated temperatures of 200 °C, 400 °C, 600 °C and 800 °C. Additionally, to understand the structural behavior in uniaxial compressive load, reinforced concrete short columns were cast, cured and tested at ambient temperature as well as after exposure to 300 °C, 600 °C and 900 °C, to know the residual strength after exposure to elevated temperature.

The findings for the residual strength of alkali-activated slag binder concrete (AASBC) indicated a substantial agreement with the results obtained for the residual strength of Portland slag cement (PSC) concrete, thereby showing the effectiveness of binder when used as a replacement of cement.

The study clearly indicates that the binder developed is an effective approach for the 100% replacement of cement in the concrete.

This study aims to investigate the compressive strength of concretes incorporating Linz-Donawitz slag (LD slag) as partial replacement for natural fine and coarse aggregates and compare them with traditional concrete.

The natural fine and coarse aggregates were replaced by weight simultaneously up to 100% with LD slag aggregates at an incremental increase of 20%. Concrete of grades M20, M25, M30, M35 and M40 were cast, cured and tested with standard cube specimens to study the density and compressive strength of reference and LD slag aggregate concretes (LDSACs). The concrete specimens were exposed to elevated temperatures, i.e. 100 to 900 °C at an equal interval of 100 °C and tested to study the variation in density and residual compressive strength.

The results from the experiments reveal that the LDSAC yields a higher density than that of the reference concrete and also undergo less density variation when exposed to elevated temperatures. In addition, the residual compressive strength of LDSAC specimens was significantly higher than that of the reference concrete.

LD slag is believed to be stronger and more durable than locally available limestone aggregates or blast furnace slag. Moreover, it is necessary to study its strength and other properties to determine whether it can be successfully used as an aggregate in concrete universally.

Use of LD slag as aggregates in concrete will convert LD slag into a value added product and as an alternative to the existing natural aggregates which will help in maintaining ecological balance and save valuable lands.

The economically weaker section of the society may now use LDSAC as waste utilization will bring down the overall cost and hence it will benefit people on large scale.

Use of LD slag as aggregate in concrete can help find an alternative to the existing natural aggregates which will save the ecosystem and at the same time help in reducing the industrial waste on a large scale.

With respect to the studies conducted so far and lack of researches on the post-heat behavior of cement mortars containing pozzolanic materials, the purpose of this paper is to investigate the post-heat mechanical characteristics (i.e. compressive, tensile and flexural strength) of cement mortars containing granulated blast-furnace slag (GBFS) and silica fume (SF). In doing so, selected temperatures include 25, 100, 250, 500, 700 and 9000c. Last, the X-ray diffraction test was conducted to study the microstructure of mixtures and subsequently, the results were presented as power-one mathematical relations.

Totally, 378 specimens were built to conduct flexural, compressive and tensile strength tests. Accordingly, these specimens include cubic and prismatic specimens with dimensions of 5 × 5 × 5 cm and 16 × 4 × 4 cm, respectively, to conduct compressive and flexural strength tests together with briquette specimen used for tensile strength test in which cement was replaced by 7, 14 and 21 per cent of SF and GBFS. To study the effect of temperature, the specimens were heated. In this respect, they were heated with a rate of 5°C/min and exposed to temperatures of 25 (ordinary temperature), 100, 250, 500, 700 and 900°C.

On the basis of the results, the most profound effect of using GBFS and SF, respectively, takes place in low (up to 250°C) and high (500°C and greater degrees) temperatures. Quantitatively, the compressive, tensile and flexural strengths were enhanced by 73 and 180 per cent, 45 and 100 per cent, 106 and 112 per cent, respectively, in low and high temperatures. In addition, as the temperature elevates, the particles of specimens containing SF and GBFS shrink less in size compared to the reference specimen.

The specimens were cured according to ASTMC192 after 28 days placement in the water basin. First, in compliance with what has been specified by the mix design, the mortar, including pozzolanic materials and superplasticizer, was prepared and then, the sampling procedure was conducted on cubic specimens with dimension of 5 × 5 × 5 mm for compressive strength test, prismatic specimens with dimensions of 16 × 4 × 4 mm for flexural strength test and last, briquette specimens were provided to conduct tensile strength tests (for each temperature and every test, three specimens were built).

The objective of this paper is to compare and evaluate the environmental performance of steel supply chains considering relevant environmental loss factors using Taguchi loss function (TLF) and design of experiments (DOE).

The different environmental loss factors in steel manufacturing supply chain were studied and the significant factors were identified. Their combined contributions along the significant factors were estimated using TLF and DOEs comparing environment losses at different scenarios.

The proposed methodology using TLF and DOEs was applied to three Indian steel manufacturing companies (Company A, Company B and Company C). The Company A with minimal average environmental loss score is found to be operating its supply chain with higher efficiency and has better environmental performance compared to the other two companies (B and C).

The results obtained are based on the study carried out in three Indian steel manufacturing companies. Therefore, the results cannot be generalized.

This paper will definitely show the direction for comparative environmental performance assessment of manufacturing industries in general and steel industries in specific considering environmental loss factors and environmental conditions. It determines individual performance across each environmental loss factor and their combined impact.

Although there is a need to have comparative performance analysis with respect to environmental losses among steel companies in developing countries such as India, but hardly any study has been reported in this direction. This work will definitely add the value to the supply chain literature in general and environment losses in steel manufacturing supply chain in specific.