scholarly journals Optimization of the Mix Formulation of Geopolymer Using Nickel-Laterite Mine Waste and Coal Fly Ash

Minerals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1144
Author(s):  
Alberto Longos ◽  
April Anne Tigue ◽  
Ithan Jessemar Dollente ◽  
Roy Alvin Malenab ◽  
Ivyleen Bernardo-Arugay ◽  
...  
Keyword(s):  
Fly Ash ◽  
Raw Materials ◽  
Mine Waste ◽  
Coal Fly Ash ◽  
Plain Concrete ◽  
Nickel Laterite ◽  
Precursor Ratio ◽  
Geopolymer Cement ◽  
Material Utilization ◽  
Lower Carbon

Geopolymer cement has been popularly studied nowadays compared to ordinary Portland cement because it demonstrated superior environmental advantages due to its lower carbon emissions and waste material utilization. This paper focuses on the formulation of geopolymer cement from nickel–laterite mine waste (NMW) and coal fly ash (CFA) as geopolymer precursors, and sodium hydroxide (SH), and sodium silicate (SS) as alkali activators. Different mix formulations of raw materials are prepared to produce a geopolymer based on an I-optimal design and obtained different compressive strengths. A mixed formulation of 50% NMW and 50% CFA, SH-to-SS ratio of 0.5, and an activator-to-precursor ratio of 0.429 yielded the highest 28 d unconfined compressive strength (UCS) of 22.10 ± 5.40 MPa. Furthermore, using an optimized formulation of 50.12% NMW, SH-to-SS ratio of 0.516, and an activator-to-precursor ratio of 0.428, a UCS value of 36.30 ± 3.60 MPa was obtained. The result implies that the synthesized geopolymer material can be potentially used for concrete structures and pavers, pedestrian pavers, light traffic pavers, and plain concrete.

scholarly journals Optimization of the Mix Formulation of Geopolymer using Nickel-laterite Mine Waste and Coal Fly Ash

2020 ◽  
Author(s):  
Alberto Jr Longos ◽  
April Anne Tigue ◽  
Ithan Jessemar Dollente ◽  
Roy Alvin Malenab ◽  
Ivyleen Bernardo-Arugay ◽  
...  
Keyword(s):  
Fly Ash ◽  
Raw Materials ◽  
Mine Waste ◽  
Coal Fly Ash ◽  
Plain Concrete ◽  
Nickel Laterite ◽  
Precursor Ratio ◽  
Geopolymer Cement ◽  
Material Utilization ◽  
Lower Carbon

Geopolymer cement has been popularly studied nowadays compared to ordinary Portland cement because it demonstrated superior environmental advantages due to its lower carbon emissions and waste material utilization. This paper focuses on the formulation of geopolymer cement from nickel-laterite mine waste (NMW) and coal fly ash (CFA) as geopolymer precursors, and sodium hydroxide (SH) and sodium silicate (SS) as alkali activators. Different mix formulations of raw materials are synthesized to produce a geopolymer based from an I-optimal design and obtained different compressive strengths. A mixed formulation of 50% NMW and 50% CFA, SH-to-SS ratio of 0.5, and an activator-to-precursor ratio of 0.429 yielded the highest 28-day unconfined compressive strength (UCS) of 22.10 ± 5.40 MPa. Furthermore, using an optimized formulation of 50.12% NMW, SH-to-SS ratio of 0.516, and an activator-to-precursor ratio of 0.428, a UCS value of 36.30 ± 3.60 MPa was obtained. The result implies that the synthesized geopolymer material can be potentially used for concrete structures and pavers, pedestrian pavers, light traffic pavers, and plain concrete.

scholarly journals Optimization of the Mix Formulation of Geopolymer using Nickel-laterite Mine Waste and Coal Fly Ash

2020 ◽  
Author(s):  
Alberto Jr Longos ◽  
April Anne Tigue ◽  
Ithan Jessemar Dollente ◽  
Roy Alvin Malenab ◽  
Ivyleen Bernardo-Arugay ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Mine Waste ◽  
Coal Fly Ash ◽  
Plain Concrete ◽  
Design Experiment ◽  
Nickel Laterite ◽  
Clay Bricks ◽  
Average Variance ◽  
Precursor Ratio

Geopolymer cement has been popularly studied nowadays compared to ordinary Portland cement but has demonstrated superior environmental advantages due to its lower carbon emissions and waste material utilization. Several studies on geopolymers have utilized various wastes like fly ash, blast furnace slag, silica fume, rice husk, or a combination of these wastes. This paper presents a mix formulation design experiment to produce a geopolymer from nickel-laterite mine waste (NMW) and coal fly ash (CFA) as a geopolymer precursor, and sodium hydroxide (SH) and sodium silicate (SS) as alkali activators. An I-optimal design experiment is used to predict the compressive strength for all the mixture's possible formulations and identify optimal proportions to minimize the average variance of prediction. A mixed formulation run of 50% NMW, SH-to-SS ratio of 0.5, and an activator-to-precursor ratio of 0.4286 yielded the highest 28-day unconfined compressive strength (UCS) of 22.1±5.4 MPa. Furthermore, using an optimized formulation of 50.12% NMW, SH-to-SS ratio of 0.516, and an activator-to-precursor ratio of 0.428, an actual UCS value of 36.26±3.6 MPa was obtained. The result implies that the synthesized geopolymer material can be potentially used for pedestrian pavers, light traffic pavers, plain concrete for leveling, building bricks, ceramic glazed facing brick, and fired clay bricks.

scholarly journals Analysis of Content of Selected Critical Elements in Fly Ash

2016 ◽  
Vol 62 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Dorota Makowska ◽  
Faustyna Wierońska
Keyword(s):  
Fly Ash ◽  
Coal Combustion ◽  
Power Plants ◽  
Raw Materials ◽  
Coal Fly Ash ◽  
New Mineral ◽  
The European Union ◽  
Cobalt Chromium ◽  
Critical Elements ◽  
Potential Source

AbstractPursuant to the new mineral policy of the European Union, searching for new sources of raw materials is required. Coal fly ash has long been considered as a potential source of a number of critical elements. Therefore, it is important to monitor the contents of the critical elements in fly ash from coal combustion. The paper presents the results of examinations of the contents of selected elements, i.e. beryllium, cobalt, chromium and germanium in fly ash from Polish power plants. The results of the conducted investigations indicate that the examined ash samples from bituminous coal combustion cannot be treated as a potential source of the analysed critical elements. The content of these elements in ash, though slightly higher than their average content in the sedimentary rocks, is, however, not high enough to make their recovery technologically and economically justified at this moment.

scholarly journals Zeolite Synthesis from Brazilian Coal Fly Ash for Removal of Zn2+ and Cd2+ from Water

2011 ◽  
Vol 356-360 ◽  
pp. 1900-1908 ◽  
Author(s):  
Juliana De Carvalho Izidoro ◽  
Denise Alves Fungaro ◽  
Shao Bin Wang
Keyword(s):  
Fly Ash ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Metal Ion ◽  
Raw Materials ◽  
Coal Fly Ash ◽  
Mineralogical Composition ◽  
Batch Process ◽  
Metal Ion Removal

A Brazilian fly ash sample (CM1) was used to synthesize zeolites by hydrothermal treatment. Products and raw materials were characterized in terms of real density (Helium Pycnometry), specific surface area (BET method), morphological analysis (SEM), chemical composition (XRF) and mineralogical composition (XRD). The zeolites (ZM1) from fly ash were used for metal ion removal from water. Results indicated that hydroxy-sodalite zeolite could be synthesized from fly ash sample. The zeolite presented higher specific surface area and lower SiO2/Al2O3ratio than the ash precursor. The adsorption showed that cadmium is more preferentially adsorbed on ZM1 than zinc. The adsorption equilibrium time for both Zn2+and Cd2+was 20 hours in a batch process. The adsorption isotherms were better fitted by the Langmuir model and the highest percentages of removal using ZM1 were obtained at pH 6 and 5 and doses of 15 and 18 g L-1for Zn2+and Cd2+, respectively. Thermodynamic studies indicated that adsorption of Zn2+and Cd2+by ZM1 was a spontaneous, endothermic process and presented an increase of disorder at the interface solid/solution.

Feasibility of Using Coal Fly Ash for Mine Waste Containment

2010 ◽  
Vol 136 (7) ◽  
pp. 682-690 ◽  
Author(s):  
Muluken B. Yeheyis ◽  
Julie Q. Shang ◽  
Ernest K. Yanful
Keyword(s):  
Fly Ash ◽  
Mine Waste ◽  
Coal Fly Ash ◽  
Waste Containment

Geopolymer Sourced with Fly Ash and Industrial Aluminum Waste for Sustainable Materials

2020 ◽  
pp. 676-696
Author(s):  
Sujitra Onutai ◽  
Sirithan Jiemsirilers ◽  
Takaomi Kobayashi
Keyword(s):  
Fly Ash ◽  
Industrial Waste ◽  
Raw Materials ◽  
Acid Resistance ◽  
High Strength ◽  
Microwave Oven ◽  
Silicate Material ◽  
High Acid ◽  
Alumino Silicate ◽  
Geopolymer Cement

Geopolymer is alumino-silicate material which can apply for many applications due to that geopolymers have several attractive properties of high strength, low permeability, high acid resistance, hazardous materials, and immobilization of toxic materials. This chapter presents synthesis of the dense and the porous structures of geopolymer by using fly ash and industrial waste as the raw materials. Aluminum hydroxide waste (Al-waste) and fly ash (FA) were used to synthesis the dense geopolymers for cement materials. The Al-waste based geopolymer influenced the geopolymer strength, when sodium hydroxide (NaOH) concentration was changed at different curing temperatures. As preliminary microwave oven was exposed in the lower NaOH paste of geopolymer, the successful synthesis of geopolymer cement was obtained. In addition, porous fly ash geopolymers was achieved using a household microwave oven. The geopolymer paste was cured within 1 min by using a microwave oven at different output power. Porous geopolymers were formed immediately as ued at 850 W power of the microwave oven.

scholarly journals Processing of high-grade zeolite nanocomposites from solid fuel combustion by-products as critical raw materials substitutes

2020 ◽  
Vol 7 ◽  
pp. 22
Author(s):  
Silviya Boycheva ◽  
Denitza Zgureva ◽  
Hristina Lazarova ◽  
Katerina Lazarova ◽  
Cyril Popov ◽  
...  
Keyword(s):  
Fly Ash ◽  
Power Plants ◽  
Raw Materials ◽  
Coal Fly Ash ◽  
Thermal Power ◽  
Coal Ash ◽  
High Grade ◽  
Fly Ash Zeolite ◽  
By Products ◽  
Critical Raw Materials

High-grade zeolite nanocomposites are synthesized utilizing solid by-products from combustion of coal for energy production in Thermal Power Plants applying alkaline aging, hydrothermal and fusion-hydrothermal activation procedures. The obtained coal ash zeolites were studied with respect to their chemical and phase composition, morphology, surface parameters and thermal properties. It was found that they are distinguished in nanocrystalline morphology and significant content of iron oxide nanoparticles (γ-Fe2O3, α-Fe2O3, γ-Fe3O4) and doping elements (Cu, Co, Mn, V, W, etc.) transferred from the raw coal ash, and therefore they are assumed as nanocomposites. Coal fly ash zeolite nanocomposites are characterized by a mixed micro-mesoporous texture, significant concentration of acidic Brønsted centers due to their high surface insaturation, high chemical and thermal stabilty. This unique combination of compositional and textural properties predetermines the application of these materials as catalysts for thermal oxidation processes, anticorrosion barrier coatings, carbon capture adsorbents, matrices for hosting functional groups, detergents etc. Examples for coal fly ash zeolite applications for substitution of critical raw materials in practice are provided.

scholarly journals Fabrication of Refractory Materials from Coal Fly Ash, Commercially Purified Kaolin, and Alumina Powders

Materials ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3406
Author(s):  
Saidu Kamara ◽  
Wei Wang ◽  
Chaoqian Ai
Keyword(s):  
Fly Ash ◽  
Power Plants ◽  
Raw Materials ◽  
Coal Fly Ash ◽  
Thermal Power ◽  
Environmental Pollutant ◽  
Clay Material ◽  
Refractory Materials ◽  
Environmental Consequences ◽  
Ceramic Compounds

Coal fly ash and kaolin are ceramic compounds utilized as raw materials in the production of refractories. Fly ash is an environmental pollutant that emanates abundantly from coal thermal power plants. The management of the large amounts of fly ash produced has been very challenging, with serious economic and environmental consequences. Kaolin, on the other hand, is a natural and synthetic clay material used in medicines, paper, plastics, and cosmetic preparations. In this research, refractory materials (cordierite (Mg2Al4Si5O18), mullite (3Al2O3·2SiO3), and kyanite (Al2SiO5)) were fabricated in four different experiments, and an assessment was made of the strength of each of the materials. Coal fly ash and kaolin were each blended with alumina as starting materials. MgO and AlF3·3H2O were each applied as additives to the reacting materials. The mixtures were molded and sintered at temperatures between 1000 °C and 1200 °C for three hours in a muffle furnace, and characterized by SEM and XRD. The analysis revealed the evolution of cordierite, mullite, and kyanite alongside other crystalline compounds. The formation of kyanite in experiment C, due to the addition of AlF3·3H2O, is unprecedented and phenomenal. The XRD figures show the corundum phases crystallize at 1100 °C in experiments A and B, and disappear at 1200 °C.

Fly Ash/Blast Furnace Slag Geopolymer Repair System as a Sustainable Solution for the Maintenance of an Existing Bridge: Materials Design and Influence on Shear Capacity under Seismic Conditions

2015 ◽  
Vol 1105 ◽  
pp. 346-354 ◽  
Author(s):  
Gianluca Nestovito ◽  
Francesco Messina
Keyword(s):  
Blast Furnace ◽  
Fly Ash ◽  
Blast Furnace Slag ◽  
Raw Materials ◽  
Coal Fly Ash ◽  
Shear Capacity ◽  
Maintenance Cost ◽  
Repair System ◽  
Geopolymer Concrete ◽  
Furnace Slag

This study deals with the paramount topic of sustainable and durable composite materials for repair of damaged existing bridge. Reinforced concrete is the most used composite system in structural design but, across several decades, it has shown some fragilities related to chemico-physical resistance. Durability improvement by means of innovative repair systems represent, therefore, a crucial economic parameter allowing a highly significant reduction of maintenance cost. A maintenance scenario is here simulated, considering a repair composite realized with a binary geopolymer binder, obtained by activating two industrial by-products, namely coal fly ash and blast furnace slag, in alkaline environment. Physico-mechanical characterization of geopolymer concrete is also performed, showing the suitability of this innovative repair system. In order to investigate the effectiveness of geopolymer, a 3D finite element model is developed in Sap2000 to represent the complex behavior of a full-scale Italian highway bridge. Numerical simulations are conducted by modeling the geopolymer concrete as a jacketing applied to the damaged piers. Results reveal that the designed repair system could increase shear capacity of bridge piers under seismic conditions, not neglecting the low cost of raw materials and the high durability of geopolymers.

Raw Materials Analysis by XRF in the Cement Industry

1992 ◽  
Vol 36 ◽  
pp. 139-144
Author(s):  
Sona H. Babikian
Keyword(s):  
Fly Ash ◽  
Raw Materials ◽  
Coal Fly Ash ◽  
Coal Ash ◽  
Analytical Techniques ◽  
Major Elements ◽  
Cement Industry ◽  
Industrial Wastes ◽  
Standard Reference Materials ◽  
Materials Used

AbstractThe sources of raw materials used in the manufacture of Portland cement include pure to argillaceous limestones, shale and clay, plus minor quantities of sand, iron ore, fly ash, coal ash and suitable industrial wastes. To ensure a high quality product, rapid - precise - reproducible and practical analytical techniques are required. Quantitative XRF analysis techniques meet those demands.For this comparative technique, the instrument used is a wavelength dispersive sequential spectrometer. The advantages and the drawbacks of the technique are discussed, along with the procedure of the specimen fused bead preparation. The importance of calibration standards and unknown samples being prepared in an identical manner, and being presented to the instrument under similar conditions, is stressed. International and synthetic standards, concentration ranges for the five major elements, mathematically generated coefficients to correct absorption and enhancement effects, and a summary of the standard error of estimates are examined and discussed.The accuracy of the method is verified by the analysis of known standard reference materials such as obsidian rock, coal fly ash, argillaceous limestone and blastfurnace slag. The values are compared with the known certified values.

Sign in / Sign up

Export Citation Format

Share Document