The gel characteristic analyses conducted by FTIR, XRD and TG/DSC show that the reaction products of alkali activated slag–fly ash–limestone blends are governed by the chain structured C–(A)–S–H type gels. The presence of limestone powder does not lead to the formation of new phases, but slightly increases both the physically and ...
Carbon dioxide (CO 2) mineralization technology has attracted significant attention, due to the synergistic terminal treatment of CO 2 and industrial waste. The combined CO 2 mineralization process with steel enterprises is a promising route to simultaneously address CO 2 emissions and SS treatment. Recently, a serial of the relevant work focus on a …
In the present study, the electric arc furnace carbon or stainless steel slag (EAF) and secondary metallurgical slag such as ladle furnace basic slag (LS) were …
The effectiveness of steel slag powder on suppressing alkali-aggregate reaction(AAR) expansion was assessed using the method of ASTM C441. The results show that mineral admixtures with steel slag ...
use of alkali metal acetates as the only source of alkalis to manufacture alkali-activated slag cements has not yet been explored. Alkali metal acetate solutions can provide sufficient alkalinity for the precursors to dissolve and alkali cations for charge-balancing reaction phases forming in the binder. Such
(7) was only used in the case of alkali excitation reaction of steel slag. (7) C ‐ S ‐ H (wt. %) = 100 ‐ ∑ (W cryst.) 2.3.3. Heat flow calorimetry. A TAM AIR 8-channel …
The carbonation reaction of steel slag is a process that utilizes CO 2 to react with calcium and magnesium minerals present in the slag, ... These bacteria are alkali-resistant bacteria, playing a catalytic and leading role in the carbonation process [82], [83]. On one hand, they catalyze carbonation reactions by secreting enzymes, and on …
The initial stages of hydration mainly consist of a reaction with alkali metal hydroxides, and the later stage is mainly an experimental reaction with Ca(OH) 2 . The final hydration product after slag activation is similar to the cement C-S-H, but the Ca/Si ratio of the slag hydration product is lower. ... Therefore, the reaction rate of steel ...
In order to compare the properties of alkali-activated carbon steel slag (CSS) and stainless steel slag (SSS), the effects of sodium hydroxide/sodium silicate solution mass ratio (NH/NS), liquid/solid ratio …
Based on the author's previous experimental results, five groups with representative quantities of mix proportions were selected for comparative analysis, as shown in Table 2, and the setting time and mechanical properties are listed in Table 3 [21].The alkali component content was added according to the percentage of slag and …
The reaction of steel slag particles proceeded at a relatively lower rate, and it was obvious that some particles have begun to be corroded and attached to the surface …
The effects of steel slag (SS) and fly ash (FA) on hydration heat, fluidity, setting time and rheological properties of alkali-activated slag (AAS) pastes with different silicate modulus (Ms) values were …
The recycling–utilization rate of steel slag in China is less than 30%. Steel slag is rich in CaO and can produce the Ca(OH)2 after hydration, which are expected to activate the pozzolanic activity of blast furnace slag. This work recycled steel slag as an alkali activator for the activation of blast furnace slag and prepared a steel slag-blast …
The hydration exothermic curves of alkali-activated steel slag cementitious material under different curing temperatures for 12 h are shown in Fig. 5 a and b, respectively. It has been observed that the hydration process of alkali-activated steel slag cementitious material is similar to that of cement at room temperature.
A new nanocomposite g-C 3 N 4 /CoAl-LDH was synthesized and implemented to make alkali-activated steel slag-based photocatalytic pervious concrete (ASSPPC). The water permeability, compressive strength, microstructure, and NO x degradation ability of ASSPPC were investigated. The results show that at lower …
To improve solid waste resource utilization and environmental sustainability, an alkali-activated material (AAM) was prepared using steel slag (SS), fly ash, blast furnace slag and alkali activators in this work. The evolutions of SS content (10–50%) and alkali equivalent (4.0–8.0%) on workability, mechanical strength and environmental …
Alkali-activated materials (AAMs), which are prepared by using various solid wastes as precursors and reacting with alkaline solutions, are gradually applied in the construction industry. However, not all solid waste precursors can exhibit good performance in the preparation of AAMs. To realize the effective utilization of phosphorus slag (PS) …
Qiu et al. [8] carried out experiments of sodium hydroxide - steel slag double alkali method of sintered flue gas desulfurization in a bubbling reactor, ... and found that the desulfurization reaction of steel slag is carried out on the surface of steel slag, the desulfurization capacity is not high, and the desulfurization capacity of steel ...
AAM-UHPC is mainly composed of hydration products generated by the reaction of steel slag powder and GGBFS powder interwoven to form a spatial network. ... Huo W., Song S., Zhang J., Yao K., Hu L. Efficient use of steel slag in alkali-activated fly ash-steel slag-ground granulated blast furnace slag ternary blends. Constr. Build. Mater. 2020 ...
Among the minor elements found in metallurgical slags, sulfur and manganese can potentially influence the corrosion process of steel embedded in alkali-activated slag cements, as both are redox-sensitive. Particularly, it is possible that these could significantly influence the corrosion process of the steel. Two types of alkali …
The alkali silica reaction (ASR) is a pathological manifestation of chemical origin and high gravity that can negatively affect the mechanical properties and durability of important concrete ...
A new type of Ni,Ca-cementitious material was firstly synthesized via a two-step reaction of alkali-activated steel slag polymerization and ion exchange. The XRF results showed that almost all the Na + ions in the matrix of Na,Ca-cementitious material were replaced by Ni 2+ ions at room temperature.
Simultaneous utilization of mine tailings and steel slag for producing geopolymers: Alkali-hydrothermal activation, workability, strength, and hydration mechanism ... the absence of the exothermic peak for sample G15–0 indicated that the hydration reaction of slag was extremely slow and the production of reactants with …
The production of alkali-activated slag cements using sodium hydroxide (abbreviated as NaOH) or sodium silicates (abbreviated as Na 2 SiO 3) (as well as potassium equivalents) as alkaline activators has been extensively investigated due to their potential for reducing the carbon footprint compared to conventional Portland cements, …
In this study, the characteristics of the alkali-silica reaction (ASR) expansion of steel slag itself, mortar bars, and concrete specimens using steel slag as aggregate are individually ...
expansion due to f-CaO, the steel slag was aged in water for over a month. 2.2. Evaluation of the Fundamental Properties of the Steel Slag As previously mentioned, steel slag is solid waste generated from the iron and steel industry [4]. Consequently, to use steel slag as aggregate in concrete, its fundamental properties must be investigated.
Ladle slag, currently an under-utilized crystalline metallurgical residue, was studied for use as a precursor for alkali activation. An activating solution containing sodium silicate and potassium hydroxide was used in activating the slag with varying compositional ratios in order to optimize the compressive strength. Ladle slag is commonly regarded …
To solve the problem of environmental pollution from stockpiling of solid waste and to achieve safe and efficient underground engineering, an environment-friendly waste-based ternary geopolymer grout was developed using blast furnace slag, sunflower stalk ash, and black rice hull ash. KOH-activated grouts were used as the controls. The …
To improve solid waste resource utilization and environmental sustainability, an alkali-activated material (AAM) was prepared using steel slag (SS), fly ash, blast furnace slag and alkali …
Shishir Mundra obtained his M.Eng. and Ph. D. at the Department of Materials Science and Engineering at University of Sheffield. His Ph. D. thesis was titled "Corrosion of steel in alkali-activated materials".. In 2018, he moved to the Federal Institute for Materials Research and T esting (BAM), Germany, and worked on developing an …
This study aims to enhance the utilization of clay bricks by maximizing the application of clay brick (CB) powder. The amount of CB was set at 50% and different percentages of steel slag (SS) powder and fly ash (FA) are added. A CB-SS-FA ternary hybrid geopolymer was prepared through alkali activation, and its performance and …
2.2. Reaction Mechanism of Alkali-Activated Steel Slag. Compared to amorphous GBFS, fly ash, and metakaolin, the biggest challenge of steel slag as a precursor is its high crystallization. Therefore, it should have different inorganic …
If the alkali-activated slag-steel slag (AASS) binder can obtain similar properties to the AASF binder, the recycling of SS will be realized. Meanwhile, the undersupply of slag and FA for the production of AAMs would also be solved. However, the application of SS to the preparation of AAMs is rarely studied. ... The reaction of slag accelerated ...
