Iron Ore Waste Research Articles

Evaluation of the Mechanical Behavior of Asphaltic Mixtures Utilizing Waste of the Processing of Iron Ore

Mineral extraction is an important operation for the economy of different countries and generates millions of tons of mining waste. In this context, and in association with the high demand for paving aggregates and the lack of raw materials for this purpose, the feasibility of using iron ore processing waste has emerged as a promising alternative. This study evaluates the physical and mechanical behavior of asphalt mixtures incorporating waste from the company Samarco S.A., collected in Mariana-MG, to replace the fine aggregate in asphalt concrete mixtures, with a view to applications in the bearing layer of local traffic roads. Two mixtures, M2 and M3, containing 20% and 17% waste, respectively, were formulated and analyzed, compared to a reference mixture, M1. Evaluations were carried out using the Marshall method parameters, mechanical tests of resilience modulus, and fatigue life under controlled tension, as well as mechanistic analysis. Brazilian mechanistic–empirical design software (MeDiNa—v 1.5.0) contributed to this analysis. This analysis revealed that, for a traffic level of N = 5 × 106 (average traffic) on a local road, pavements containing the M1 and M3 mixtures had the same layer thicknesses (6.9 cm), as well as the same fatigue class, equal to 1. The pavement with the M2 mixture had the thickest asphalt layer (8.2 cm) and a lower fatigue class equal to 0. But if compared in terms of the percentage of cracked area over 10 years, it still offers ideal performance conditions compared to the M1 and M3 mixes. Thus, it can be considered feasible to replace fine aggregate with iron ore waste in asphalt concrete for use on local roads in the region without altering the bearing capacity of the pavement.

Influence of FexOy and Al2O3 Contents on the Thermal Stability of Iron Ore-Waste Fibers: Key Mechanisms and Control.

Traditional rock wool fibres are susceptible to crystallization and pulverization. To mitigate this, glass fibres were produced from iron ore waste (IOW). When the ratio of Fe2+ and Fe3+ is 1:3 and the Al2O3 content is 10 wt.%, increasing the FexOy content enhances the thermal stability.At an FexOy content of 17-19% and an Al2O3 content of 10-13%, the glass transition temperature (Tg) peaked. Increasing the FexOy content from 10% to 20% enhanced the stability of Si-O and Al-O bonds and increased bridged oxygen, stabilizing the structure. Here, Fe2+ balances structural charges, while Fe3+ replaces some Al atoms in the network. When the Al2O3 content is 10-13% and the FexOy content is 17-19%, the thermal stability of the IOW rock glass reaches its optimal level. At 20% FexOy content, the structure becomes three-dimensional and cyclic, increasing polymerization. Consequently, incorporating FexOy alongside a 10% Al2O3 content improves thermal stability, supporting the development of high-stability rock wool from IOW. This approach also enhances the refractory properties of rock wool fibres within the FexOy-Al2O3-SiO2-MgO-CaO system.

Exploring the Use of Iron Ore Tailings in Concrete by Partial Replacement of Fine Aggregates

Concrete is the most durable, resilient, available and affordable material in the built environment. The manufacture of large quantities of iron ore has created difficulties for the environment and disposal. The utilization of IOT as fine aggregate in building material production is relatively feasible. Experiments were conducted to determine the suitability of iron ore tailings as replacement of fine aggregates for concrete. The iron ore waste was collected from Gua Iron Mines, Singhbum. Mix Design was carried out for concrete of grade M35 using standard practice for selecting proportions for normal weight. Iron ore waste replaced with fine aggregates in mixes by 30% and 35% respectively. The materials used for M35 grade of concrete is coarse aggregate 10-20mm, fine aggregate is of Zone 2, cement of 53 grade. Tests were performed on materials, for cement and fine Aggregate Fineness test, Specific Gravity were performed. Water absorption test, specific gravity, Impact value these were performed for Coarse aggregate. It was observed that compression values of concrete for 30% for 3 days its 13.703 Mpa, For 7 days its 16.503 Mpa, and for 28 it was 28.033 Mpa

Recycling Iron Ore Waste through Low-Cost Paving Techniques

Research on road construction has evolved and advanced. Environmental sustainability considerations are now an integral part of the specific focus of these infrastructure projects. This study investigated the feasibility of recycling on iron ore reject through cost-effective pavement techniques, demonstrating significant improvements in the performance of stabilized mixtures with the addition of anti-dust treatment. The mineralogical and chemical analysis of the reject, coupled with the conducted priming tests (LWT and WTAT), highlighted the effectiveness and promising application of these materials in construction. Under a load of 33 kg, the anti-dust-treated mixture showed a deformation of 5.3 mm, compared to 7.76 mm for the stabilized reject–emulsion mixture. Similar improvements were observed in reject–soil–emulsion mixtures, with a sinking of 4.16 mm for anti-dust-treated specimens compared to 6.99 mm for stabilized mixtures. The results of the WTAT test corroborated the effectiveness of the layer formed by the anti-dust treatment; in all cases, the mass loss was less than 2%. These findings have significant implications for sustainability in construction, contributing to environmental conservation and resource efficiency.

Native Plant Species as an Alternative to Rehabilitate Iron Ore Waste Piles in Carajás Mineral Province, Brazil

ABSTRACT The selection of promising and appropriate plant species and knowledge of their effects on the soil are essential for mineland rehabilitation success. The present study evaluated the effects of three different plant seed cocktails on fertility, soil cover, and erosion control in two iron waste piles in the Carajás Mineral Province, Eastern Amazon, Brazil. The three different seed cocktails were: commercial (only commercial species); native (only species native of Carajás); mixed (native and commercial species); and a control treatment (without seed application). Additionally, tillers from native grasses from Carajás were planted in one of the waste piles. The cocktails were applied by hydroseeding together with fertilizer, mulch, organic compost, and a tackifier. Analyses were performed at 12 and 24 months after the seeding in the waste piles. In general, all cocktails contributed to vegetation establishment, organic matter accumulation, and increased soil fertility. The commercial cocktail stands out due to its ability to improve soil fertility. Native species showed the best cover performance, and less soil loss, highlighting their use for effective control of soil erosion. Thus, native species have the potential for use in rehabilitation projects involving iron waste piles in the Amazon. This is especially relevant because the use of native plant species is mandatory and a declared rehabilitation target.

Analysis of the mechanical behavior of an alternative sand for foundry molding

The exploration and beneficiation of iron ore result in a substantial generation of waste, predominantly directed towards tailings dams, heightening environmental concerns. Faced with this environmental challenge, numerous studies have been devoted to seeking sustainable solutions, aiming at the utilization of waste in various sectors of the economy. In this context, this study focuses on the technical feasibility investigation of using sandy iron ore waste as molding sand in foundry processes. Foundry molding sand, crucial in casting, must meet specific requirements and exhibit particular characteristics to effectively fulfill its function. To address this issue, test specimens were fabricated using three distinct types of sands: Standard Sand, Sand 01 (without magnetic separation), and Sand 02 (subjected to magnetic separation), combined with two binders (bentonite and sodium silicate). Subsequently, the test specimens underwent mechanical tests for tension, flexure, and compression, with the aim of evaluating their ability to withstand applied forces. The results of these tests revealed that Sand 02, when combined with sodium silicate, demonstrated satisfactory performance, in accordance with established standards and studies for obtaining sands intended for molding in foundry processes.

Ferrock - A Carbon Negative Sustainable Concrete : A Review

Cement industry further going to grow at high speed with Government of India giving boost to infrastructure projects and housing facilities. As per the World business council for sustainable development (WBCSD, 2005) the cement industry produces 5% of global man-made carbon dioxide, a major gas contributing to climate change and responsible for global warming. A product called Ferrock was created as a result, concentrating on the reduction of carbon emissions as well as the utilization of waste materials for a better environment. This study examines this product that moves in the direction of waste reduction and carbon neutrality. It demonstrates the most effective use of iron ore waste powder obtained during the mining process, which is often dumped outside of the mines and causes air pollution, health risks, and bigger area use. By having a strength-gaining mechanism that is unlike cement's and unique among cement supplements, the product indirectly lowers the carbon dioxide discharged into the atmosphere. For greater strength in terms of compression and tensile strengths and to achieve desired qualities, ferrock is subjected to a curing process that includes carbonation and air curing over a range of days. Because it uses waste effectively and has a negative carbon footprint, ferrock is a more promising environmentally friendly binding material.

In-depth study on the synergistic conversion mechanism of iron ore with waste biochar for co-producing directly reduced iron (DRI) and syngas

Waste biochar and waste iron ore sintering dust were synergistically resourced to produce directly reduced iron (DRI) and combustible syngas in this study. A solid product with 92.45 % metallization ratio and a combustible syngas (65.69 % CO, 8.03 % CH4) with a yield of 1170.9 ml/g were obtained at 1000 °C for 60 min with 1.2 mol(C/Fe). The CO production of biochar conversion was increased by adding iron ore sintering dust, about 769.3 mL/g at 1000 °C for 60 min, 7.17 times that of biochar pyrolysis alone (107.3 mL/g). The co-conversion was the generation, growth and aggregation of iron grains for the sintering dust. This synergistic conversion achieved the recycling of these two solid waste resources to produce high-value DRI and high-calorific-value syngas, as industrial raw materials and fuels, saving fossil resources and fuels. The biochar pyrolysis, gasification and the reconversion of pyrolysis products occurred during their co-conversion. The gas production of biochar pyrolysis and gasification were 280.7 ml/g and 933.8 ml/g, while the reduction degrees of iron ore by the gas and solid from biochar pyrolysis were 12.64 % and 79.98 %. Their well-mixed state during the co-conversion process facilitated the reconversions of pyrolysis products by improving diffusion efficiency.

Use of iron ore tailings as partial replacement for cement on cementitious composites production with vegetable fibers

The mining industry has been expanding and consequently increasing the associated environmental impacts, especially regarding this process's high volume of iron ore tailings (IOT) disposal. The best way to solve the problems caused by IOT is to develop large-scale utilization technologies that may consume large quantities of it. This study aims to evaluate the influence of incorporating IOTs on the mechanical, physical, microstructural, and morphological properties of extruded fiber-cement reinforced with eucalyptus cellulose pulp. For its use, IOT was characterized by the inhibition index, pozzolanic test, and granulometric, chemical, morphological, and X-ray diffraction analyses. The fiber-cement flat slabs were prepared by replacing cement using 10%, 20%, 30%, and 40% of IOT and the control treatment, generating specimens measuring 20x30x200mm (height x width x length). The composites were characterized for physical, mechanical, and microstructural properties before and after exposure to weathering by accelerated aging test. This study showed an improvement in fiber durability with the increase in IOT content as a function of the waste’s pozzolanic activity and an improvement in physical properties using 10% cement replaced by IOT. All treatments tested at 28 days presented values within trading standards limits. However, the treatments with 10% and 20% of IOT met the most demanding criteria. Thus, using iron ore waste as a substitute for raw materials in cementitious composites may reduce the difficulties of IOT disposal and save natural resources, leading to more sustainable constructions.

Ultra-high-performance concrete with Iron ore tailings and non-metallic and hybrid fibers-A comprehensive experimental study

This research discusses the behavior of ultra-high-performance concrete (UHPC) specimens made with dumped waste iron ore tailing (IOT) as a fine aggregate in the mix by 30% and 40% in volume fraction along with mono and hybrid fiber incorporation. Basalt fibers of 1%, 2%, and 3%, polypropylene fibers of 0.18%, 0.20%, and 0.22%, and glass fibers of 1%, 1.5%, and 2% of volume fractions were the non-metallic fibers used. Steel fibers as a metallic factor were kept 1% constant throughout the study. The water-to-binder ratio was maintained between 0.15 and 0.17 after sufficient trials. A high-range water reducer was utilized to improve the flowability of the mix. The experimental investigations confirmed that the SG2 mix with 1% steel and 1.5% glass fiber, and 30% IOT, exhibited improved tensile and impact strength compared to standard conventional concrete. This combination exposed an impact energy of 4.05 × 105 kJ for the first crack and 2.7 × 106 kJ for collapse. The energy taken by the specimen between the first crack and the collapse was about 2.3 × 106 kJ. The microstructure was analyzed using Scanning Electron Microscopy. The non–metallic fibers with dominant mechanical properties were thermogravimetrically analyzed.

Variasi Penggunaan Limbah Crushing Plant Bijih Besi Gunung Batu Sebagai Agregat Halus Terhadap Mutu Beton

The increasing demand for concrete as a construction material has resulted in the depletion of natural resources. This motivates the construction industry to continue to innovate in the manufacture of concrete. The utilization of iron ore waste as a substitute for fine aggregate is one of the solutions. This study aims to determine the optimum composition of iron ore waste as a substitute for fine aggregate on compressive test strength and economic value of concrete mix materials. This study used coarse aggregate from the quarry location of Mount Batu PTP Pelaihari District, Tanah Laut Regency, fine aggregate from the iron ore crushing plant location from the stockpile of Perusda Baratala and ex. Palangkaraya. The testing at the UPT Construction Material Testing Laboratory DPUPRP Tanah Laut Regency, South Kalimantan Province. The results showed that concrete using fine aggregate/sand ex. Palangkaraya has a concrete quality of K-235.94 kg/cm2 or fc'= 19.583 Mpa. As a result, it was found that the concrete mixes were more efficient than the concrete mixes used in the concrete batching plant, and that the concrete mixes were more efficient than the concrete mixes used in the concrete batching plant AK (Coarse aggregat) 54%: AH (fine aggregates) 45% has a concrete quality of K-257.29 kg/cm2 or fc'= 22.849 Mpa. This shows that iron ore waste fine aggregate can be used in concrete mixes

Laboratory investigation of solid wastes combined with tunnel slag in cement stabilized base of asphalt pavement

To coordinate the disposal and resource utilization of bulk solid waste iron ore tailings sand (IOTS) and hazardous solid waste phosphogypsum (PG), this paper has carried out the research of using the two and the tunnel slag in the pavement base, including unconfined compressive strength, splitting strength, compressive resilience modulus, frost resistance, temperature shrinkage, and dry shrinkage tests. According to the characteristics of phosphogypsum (PG), the water stability, delayed compaction, and leaching of toxic substances were studied, and the mechanism was analyzed by SEM and XRD. It is concluded that tunnel slag and IOTS are great filling materials; The inclusion of PG inhibited the hydration of cement, which results in the reduction of unconfined compressive strength and splitting strength in the early stage, and the higher mean coefficient of thermal contraction; When the content of PG did not exceed 6%, the frost resistance, water stability, and drying shrinkage coefficient performed well, and the delayed forming strength had almost no loss, providing support for the continuous construction technology of the road base and the inhibition of reflective cracks. Applying a large number of solid wastes to road engineering can not only efficiently handle various waste buildup problems but also produce a new form of road materials with important social, economic, and environmental benefits.

Laser-assisted reduction of iron ore using aluminum powder

This study reports on the laser-assisted reduction of iron ore waste using Al powder as a reducing agent. Due to climate change and the global warming situation, it has become of paramount importance to search for and/or develop green and sustainable processes for iron and steel production. In this regard, a new method for iron ore utilization is proposed in this work, investigating the possibility of iron ore waste reduction via metallothermic reaction with Al powder. Laser processing of iron ore fines was performed, focusing on the Fe2O3–Al interaction behavior and extent of the iron ore reduction. The reaction between the materials proceeded in a rather intense uncontrolled manner, which led to the formation of Fe-rich domains and alumina as two separate phases. In addition, a combination of Al2O3 and Fe2O3 melts, as well as transitional areas such as intermetallics, was observed, suggesting the occurrence of incomplete reduction reaction in isolated regions. The reduced iron droplets were prone to acquire a sphere-like shape and concentrated mainly near the surface of the Al2O3 melt or at the interface with the iron oxide. Scanning electron microscopy, energy-dispersive x-ray spectroscopy, and wavelength-dispersive x-ray spectroscopy analyses were employed to analyze the chemical composition, microstructure, and morphological appearances of the reaction products. High-speed imaging was used to study the process phenomena and observe differences in the movement behavior of the particles. Furthermore, the measurements acquired from x-ray computed microtomography revealed that approximately 2.4% of iron was reduced during the laser processing of Fe2O3–Al powder bed, most likely due to an insufficient reaction time or inappropriate equivalence ratio of the two components.

Developing novel pothole patching mixtures utilizing iron ore waste as substitute to conventional aggregates with anti-stripping agent

Development of potholes on roads and streets of prominent cities in India after the onset of monsoons is a common phenomenon. The remedy used for restoration of potholes is termed as “Patching” which prevents rapid pavement deterioration and provides smooth traffic flow. The present article aims at developing novel pothole patching mixtures utilizing Iron Ore Waste (IOW) as substitute to conventional aggregates (CA) with anti-stripping agent (ASA). Mix design, adhesion, cohesion, and moisture sensitivity of pothole patching mixtures were evaluated. Mix design properties were evaluated adopting the Marshall method, adhesion properties were evaluated as per Virginia Department of Transportation (DOT) test procedure, cohesion properties were evaluated as per AASHTO TP-44–94, and moisture sensitivity was evaluated using modified Lottman test. The strength of the initial and fully cured stages improved when IOW was substituted with conventional aggregates, and it was higher than 5.1 kN. As for Cohesion, every substance under investigation retained more than 60% of its original composition at the initial test conditions (4 °C and five blows). When tested at 25 °C and five blows, cohesiveness exhibited the same pattern as when tested at 4 °C. The findings of the adhesive test showed that IOW-Z has a maximum adhesion time of 35 s. Moreover, IOW-based pothole patching mixtures outperformed CA-based pothole patching mixtures in terms of resistance to moisture sensitivity. Results also indicate addition of ASA improved adhesion, cohesion, and moisture sensitivity properties of pothole patching mixtures regardless of aggregate type.

Stabilizing black cotton soil using iron ore waste

Using discarded iron ore powder to settle subgrade soil will improve the characteristics of black cotton soil. The soil's engineering properties are analysed using various tests, such as specific gravity, grain size analysis, Atterberg's limits, compaction properties, and unconfined compressive strength. These tests examine the classification of the soil, the optimum moisture content (OMC), the maximum dry density (MDD), the strength of the soil, and other variables. The black cotton soil (BCS) was taken from Ghatkesar Mandal in the Malkalgiri-Medchal region, while the iron ore was procured from a small-scale local enterprise. For this, a clay soil sample with a medium degree of plasticity was combined with iron ore powder in concentrations ranging from 0% to 20% with a 5% increment. The data obtained demonstrated a steady rise in specific gravity with the addition of scrap iron ore and raised from 2.54 to 2.81 when it comes to unconfined compressive strength. Adding more iron ore increased the UCS to stabilize the soil from 149.31kPa to 232.22kPa. The OMC increased from 16% to 12.5%, MDD from 1.86gm/cc to 1.98gm/cc and Plasticity Index from 42.8% to 28.08%. For all mixes, the soil is well-graded. The results demonstrate that iron ore waste can successfully stabilize the soil.

Synthesis of schorl doped iron ore tailings glass-ceramics with superior performance

The diopside-based glass-ceramics were prepared by using iron ore tailings as main raw materials and schorl as additive. The addition of schorl was found to effectively reduce the crystallization activation energy and to promote the crystallization of diopside. The diopside and schorl were evenly distributed and sufficiently interlocked together, which improved the flexural strength and bulk density of glass-ceramics. The far-infrared emissivity of glass-ceramics increased with the addition of schorl due to intrinsic far-infrared characteristics of schorl, while the replacement of Mg and Si ions in diopside by Fe ions also contributed to the enhancing far-infrared emissivity due to lattice distortion and symmetry reduction of diopside crystal. At 10 wt.% schorl addition, the glass-ceramics was at its best, with flexural strength of 107.03 MPa, bulk density of 2.66 g/cm3, and far-infrared emissivity of 0.928. This work lays foundation to manufacture of high value glass-ceramics with superior properties utilizing waste iron ore tailings and schorl.

Iron ore waste combined with lysozyme-producing bacteria to promote sludge reduction: Performance and mechanism

Due to the complex structure of sludge, sludge hydrolysis becomes the limiting factor for sludge digestion. In this study, a combined treatment system of lysozyme-producing bacteria and iron ore waste was established, and the lysozyme secreted by the enzyme-producing bacteria was used to realize the cracking of the sludge cell structure to achieve the purpose of reducing sludge. The results showed that the best hydrolysis effect could be achieved when the sintered ore dosage was 1.50 g L−1 and lysozyme inoculation dosage was 3 %. At 20 h, the release amount of soluble chemical oxygen demand (SCOD) was 1877.34 mg L−1, and the concentration of protein and polysaccharide increased by 226.64 and 114.51 mg L−1, respectively, which indicated that the sludge microorganisms released a large amount of intracellular substances. The removal rate of suspended solids (SS) concentration in the combined treatment system was 3.37 times that of the control group. The results of sludge morphology analysis showed that the sludge structure was destroyed and the particle size decreased. The addition of sinter reduced the Zeta potential of sludge, promoted electron transfer between microorganisms, and improved lysozyme production efficiency of enzyme-producing bacteria. Proteobacteria plays a dominant role in the combined treatment system. The combined treatment system significantly improved metabolic capacity and iron utilization capacity of the microbial community, which may be the mechanism for the combined treatment system to promote sludge reduction.

Performance of hydrogel immobilized bioreactors combined with different iron ore wastes for denitrification and removal of copper and lead: Optimization and possible mechanism

Reasonable and efficient removal of mixed pollutants (nitrate and heavy metals) in industrial wastewater under heavy metal pollution has attracted more attention in recent years. The target strain Aquabacterium sp. XL4 was immobilized with different iron ore wastes (IOW) using polyvinyl alcohol (PVA) to construct four immobilized bioreactors. The results showed that when the ratio of C/N was 1.5 and the hydraulic retention time (HRT) was 8.0h, the denitrification performance of the bioreactor was the best, and the maximum denitrification efficiency of the bioreactor with sponge iron (SI) as the iron source was 97.19% (2.42mg L–1 h–1). Furthermore, by adjusting the concentration of Cu2+ and Pb2+, the stress behavior of the bioreactor to heavy metals under the influence of each IOW was investigated. The bioreactor has stronger tolerance and removal efficiency to Pb2+ and Cu2+ in the presence of pellets ore (PO) and refined iron ore (RO), respectively. Moreover, the high–throughput data showed that Aquabacterium accounted for a high proportion in the immobilized bioreactor, and the prediction of functional genes based on the KEGG database showed that the addition of IOW was closely related to the acceleration of nitrate transformation and the inflow and outflow of iron in cells.

Compressive strengths of concrete by partially replacing sand with iron-ore waste

Sand is extracted at a rate more than its restoration. Nevertheless, the availability of sand in the growing demand of the construction industry remains a challenge due to cost and quality problems. This study investigates the compressive strength of concrete by partially replacing sand with iron-ore waste. Experimental investigations were conducted to study the compressive strength, physical, mechanical and fresh property of concrete containing iron-ore waste. During the experiment, concrete cubes were prepared with 10-100% composition of iron ore waste to evaluate their compressive strength. Results from the experimentation revealed that, concrete cubes prepared by partially replacing sand with iron ore waste often yield a better compressive strength than a conventional concrete. More so, the densities of concrete cubes were observed to remain consistent but increased slightly, notably at 10% and 20% of waste replacement. Meanwhile, at 30% waste replacement, there was reduction in compressive strength at 28days curing age and this reduction continued as percentage iron ore increased towards 100%. Also, increase in compressive strength of concrete cubes was observed at 10-20% sand replacement with iron ore. It was therefore established that concrete produced under 10% and 20% replacement, can be utilized for all construction purposes requiring concrete.

Alkali-activated bricks made with mining waste iron ore tailings

In India, the enormous growth in the housing sector has put tremendous pressure on construction materials such as bricks. Conventional brick production methods include fired bricks and cement blocks. However, conventional methods significantly contribute to environmental carbon emissions and therefore alternative brick production methods have caught the attention of several researchers. Furthermore, the waste generated in various industries can be a useful resource for the construction industry, and in particular, voluminous waste is generated during the beneficiation stage of iron ore concentrate, which can be integrated into the construction industry to achieve sustainable practice. With this quest in mind, this study proposes the utilization of mining waste iron ore tailing (IOT) in alkali-activated bricks. For this purpose, six different brick compositions were synthesized with fly ash, GGBS, and IOT along with Na2SiO3 sol. The raw materials were characterized using various techniques such as X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscope (SEM), and particle size analysis (PSA). Furthermore, a series of standard tests were conducted on the developed bricks to evaluate their strength and durability properties. The developed bricks have presented a maximum compressive strength of 18.45 MPa and minimum water absorption of 12.6%. Besides, the alkali-activated bricks have shown excellent resistance to brick ageing which was attributed to improvement in the microstructure of bricks due to the filling up of voids with products of the polymeric reaction. Finally, it was interesting to notice that with 8% Na2SiO3 as an alkaline activator and with the combination of fly ash and GGBS more than 50% IOT can be utilized to produce good quality bricks at ambient curing conditions.