scholarly journals The Influencing Factors for Volume Stability of Ladle Slag

Processes ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 92
Author(s):  
Tung-Hsuan Lu ◽  
Ying-Liang Chen ◽  
Hong-Paul Wang ◽  
Juu-En Chang

The purpose of this study was to investigate the mechanism causing the unsoundness of ladle slag. Calcination temperature may have an impact on the level of reactivity of f-CaO. When CaO was produced at a higher temperature, the reactivity of CaO was lower. For example, dead burnt CaO (DCaO) was produced at higher temperatures than light burnt CaO (LCaO); therefore, DCaO had less reactivity than LCaO. In a hydration test, DCaO (1500 °C) showed 62 times lower reactivity than LCaO (900 °C), which meant that DCaO would result in the delay of hydration of CaO easily. Additionally, DCaO would cause unsoundness more easily than LCaO when adding the same number of cementitious materials. For this reason, using ASTM C114-18 (Standard Test Methods for Chemical Analysis of Hydraulic Cement) to quantify DCaO content may underestimate DCaO content by up to 20%. Conversely, this method was more suitable for f-CaO since it had high reactivity. Moreover, this study demonstrated that ladle slag would cause unsoundness when added into the cementitious material because it was produced from a higher temperature process (over 1500 °C), which generates the DCaO. Therefore, when reusing ladle slag, the problem of low reactivity of DCaO should be considered.

2014 ◽  
Vol 599 ◽  
pp. 98-102 ◽  
Author(s):  
Jiang Feng Li ◽  
Xiu Cheng Luo ◽  
Meng Ke Sun ◽  
Wei Guo Shen ◽  
Bing Cao ◽  
...  

The production of steel slag, a byproduct of the steel refining keeps increasing rapidly and it reached 90.42 million tons in 2011 in China, but its comprehensive utilization ratio is only 22% and far less than the ratio of 65% in Europe. Main chemical compositions of steel slag are CaO, SiO2, Al2O3, FeO, Fe2O3, MgO, MnO, P2O5 and so on, C3S, C2S, C3MS2, RO phase are its common minerals. Due to its high reactivity and Ferro content, steel slag has high potential utilization as supplementary hydraulic cementitious materials or cement clinker meal in cement industry. A method of multiple phased sintering was presented, it can break through the bottlenecks for the steel slag using in the cement industry, e.g. volume stability and grindability ,the carbon emission of cement industry is slashed, it is an effective new approach to massively utilize steel slag in cement industry.


2021 ◽  
Vol 11 (11) ◽  
pp. 5294
Author(s):  
Peer Decker ◽  
Ines Zerbin ◽  
Luisa Marzoli ◽  
Marcel Rosefort

Two different intergranular corrosion tests were performed on EN AW-6016 sheet material, an ISO 11846:1995-based test with varying solution amounts and acid concentrations, and a standard test of an automotive company (PV1113, VW-Audi). The average intergranular corrosion depth was determined via optical microscopy. The differences in the intergranular corrosion depths were then discussed with regard to the applicability and quality of the two different test methods. The influence of varying test parameters for ISO 11846:1995 was discussed as well. The determined IGC depths were found to be strongly dependent on the testing parameters, which will therefore have a pronounced influence on the determined IGC susceptibility of a material. In general, ISO 11846:1995 tests resulted in a significantly lower corrosion speed, and the corrosive attack was found to be primarily along grain boundaries.


Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4992
Author(s):  
Ruimeng Shi ◽  
Xiaoming Li ◽  
Yaru Cui ◽  
Junxue Zhao ◽  
Chong Zou ◽  
...  

Nickel slags can be produced through ferronickel preparation by the pyrometallurgical processing of laterite nickel ores; however, such techniques are underutilized at present, and serious environmental problems arise from the stockpiling of such nickel ores. In this study, a modification to the process of ferronickel preparation by the direct reduction of carbon bases in laterite nickel ores is proposed. The gangue from the ore is used as a raw material to prepare a cementitious material, with the main components of tricalcium silicate and tricalcium aluminate. By using FactSage software, thermodynamic calculations are performed to analyze the reduction of nickel and iron and the effect of reduction on the formation of tricalcium silicate and tricalcium aluminate. The feasibility of a coupled process to prepare ferronickel and cementitious materials by the direct reduction of laterite nickel ore and gangue calcination, respectively, is discussed under varying thermodynamic conditions. Different warming strategies are applied to experimentally verify the coupled reactions. The coupled preparation of ferronickel and cementitious materials with calcium silicate and calcium aluminate as the main phases in the same experimental process is realized.


2021 ◽  
Vol 8 (2) ◽  
pp. 48-53
Author(s):  
Reannan Riedy ◽  
Meredith McQuerry

To improve the comfort of agricultural workers, a T-shirt with a printed active cooling finish was evaluated to determine if it would meet the wash life durability and performance expectations of such an arduous application. Six shirts with a printed phase change material (PCM) finish and six shirts without (control) were washed 50 times to replicate a typical consumer wash life. Shirts were evaluated for absorbency, dimensional change, colorfastness, crocking, abrasion resistance, soil release, and smoothness retention according to AATCC and ASTM standard test methods. Testing was conducted before laundering and after 1, 5, 10, 20, 30, 35, 40, 45, and 50 consumer laundry (CL) cycles. Absorbency and dimensional change were significantly influenced by the PCM finish. Results demonstrate the appropriateness of adopting such a finish technology for agricultural worker clothing applications.


2013 ◽  
Author(s):  
Roger Bostelman ◽  
Richard Norcross ◽  
Joe Falco ◽  
Jeremy Marvel
Keyword(s):  

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