6 results on '"ZHANG Yu-zhu"'
Search Results
2. Investigation on the effect of MgO content on the crystallization behavior of synthetic BF slag.
- Author
-
Ren, Qian-Qian, Zhang, Yu-Zhu, Long, Yue, Zou, Zong-Shu, Chen, Shao-Sheng, and Li, Jie
- Subjects
SLAG ,CRYSTALLIZATION ,COMPUTER simulation ,MAGNESIUM oxide ,AKERMANITE ,ADDITIVES - Abstract
The crystallization of molten blast furnace (BF) slag can increase its viscosity and reduce its liquidity; it can also affect the quality of slag fibers following their manufacture. The crystallization behavior of BF slag is influenced by its chemical composition. In this study, four synthetic BF slags with various MgO contents, ranging from 6 to 12%, were investigated. FactSage simulations were performed to predict the types of crystallized phases as well as their mass fractions that are developed within the synthetic BF slags during the cooling process. To verify the validity of FactSage simulation, X-ray diffraction and scanning electron microscope-backscattered electron imaging, where the equipment was coupled to an energy-dispersive spectrometer, were performed to explore the mineralogical compositions and morphologies of the synthetic BF slags. Experiments using the hot thermocouple technique were performed to identify the initial crystallization temperatures of the synthetic BF slags. The results indicate that the observed phases of the synthetic BF slags were primarily composed of akermanite (2CaO · MgO · 2SiO
2 ) and gehlenite (2CaO · Al2 O3 · SiO2 ), which could form a solid solution, melilite, and control the initial crystallization temperature. The initial crystallization temperature increased as the MgO content of the slag increased. A low initial crystallization temperature was achieved in the cases of the synthetic BF slag samples with MgO contents of 6-8%; these slags were considered suitable for the manufacture of slag fiber. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
3. Notice of Retraction: Research on Hexavalent Chromium Removal from Wastewater by Gas Quenching Steel Slag
- Author
-
Zhang Yu-zhu, Li Jun-guo, and Wei Ling-hong
- Subjects
Pollutant ,Precipitation (chemistry) ,Chemistry ,Metallurgy ,Slag ,chemistry.chemical_element ,chemistry.chemical_compound ,Chromium ,Wastewater ,visual_art ,visual_art.visual_art_medium ,Sewage treatment ,Hexavalent chromium ,Inert gas ,Nuclear chemistry - Abstract
Gas quenching steel slag (GQSS), which was prepared by gas quenching equipment under inert atmosphere, possessed some advantages for pollutants removal from wastewater. Static state experiment has been carried on to investigate Cr(VI) removal from wastewater by GQSS. The results indicated that initial pH value, solid-liquid ratio, Cr(VI) original concentration and dissolved oxygen in solution have significant influence on Cr(VI) removal percentage. Cr(VI) solution had better to be controlled in acidic condition because Cr(VI) reduction could be restrained in alkaline solution. On the other hand, the initial pH value could not much lower because precipitation of Cr(III) could be inhibited. To improve Cr(VI) removal percentage, the solid-liquid ratio should be controlled at 1:100. Under different original concentrations, Cr(VI) removal percentage was in the range of from 20% to 45% because the GQSS without any further treatment and modification.
- Published
- 2011
4. Preparation and Properties of Slag Wool Board using Modified Polyvinyl Alcohol as Binder.
- Author
-
Zhang, Zun-Qian, Zhang, Yu-Zhu, Yang, Ai-Min, Xing, Hong-Wei, Tian, Tie-Lei, and Li, Zhi-Hui
- Subjects
MINERAL wool manufacturing ,POLYVINYL alcohol ,MICROSTRUCTURE ,THERMAL conductivity ,MATERIALS compression testing - Abstract
Slag wool boards were produced by using slag wool as the main raw material and adding modified polyvinyl alcohol (PVA) as the binder. The microstructure, thermal conductivity, compression strength, hydrophobicity, and other properties of the slag wool board were analyzed by using scanning electron microscopy, thermal conductivity tester, electronic universal testing machine, and other equipments. Also, the influence of different types and amount of binder on the properties of the slag wool board was studied. The results show that the addition of silica sol can improve the high temperature resistance of the slag wool board, and the addition of borax can improve the hydrophobic rate and compression strength of the slag wool board. Also, the concentration of PVA has obvious influence on the usage of silica sol and borax. In this study, we found that the optimal ratio of the binder should be 3 wt% addition of PVA, 20 wt% addition of silica sol, and 0.2 wt% of borax (relative to the amount of PVA), under the condition of satisfying the performance index of slag wool board and the convenience to spray the adhesive. [ABSTRACT FROM PUBLISHER]
- Published
- 2016
- Full Text
- View/download PDF
5. Cementitious Behavior of Argon Oxygen Decarburization Stainless Steel Slag and Its Stabilization on Chromium.
- Author
-
Wang, Ya-Jun, Zeng, Ya-Nan, Li, Jun-Guo, and Zhang, Yu-Zhu
- Subjects
DECARBURIZATION of steel ,STAINLESS steel ,CHROMIUM ,HEAT of hydration ,ARGON ,SLAG ,LEACHING ,HEXAVALENT chromium - Abstract
The study mainly aims at the potential of Argon Oxygen Decarburization Slag (AODS) as a supplementary cementitious material and explores the mechanisms of stabilization/solidification (S/S) of chromium in cement-based composite pastes. The basic cementitious parameters, such as water requirement, setting time, soundness, hydration characteristics, and strength indexes of composite binders, were examined through standard methods. The results showed that the most beneficial mineral phase in AODS for cementitious behavior was beta dicalcium silicate (β-C
2 S). The utilization of a higher AODS dosage in composite binders increased the water requirement and the setting time, while it decreased the hydration heat and the strength indexes. Although the AODS possessed limited cementitious properties, it conformed the Grade II steel slag powder qualified for concrete and cement. Sequential leaching tests were conducted targeting the leachability of chromium in the pastes with different AODS dosage and curing time. Results showed that with the lower AODS dosage and the longer curing time, the S/S efficiency for chromium leaching from the composite paste was better. Utilization of AODS as a cement substitute not only can recycle this solid waste and decrease the emission of CO2 concerning cement production, but also helps to effectively reduce the chromium leaching risk. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
6. Carbonation of argon oxygen decarburization stainless steel slag and its effect on chromium leachability.
- Author
-
Wang, Ya-Jun, Zeng, Ya-Nan, Li, Jun-Guo, Zhang, Yu-Zhu, Zhang, Ya-Jing, and Zhao, Qing-Zhong
- Subjects
- *
DECARBURIZATION of steel , *STAINLESS steel , *CHROMIUM , *SILICA gel , *ARGON , *SLAG - Abstract
This study focuses on evaluating the carbonation potential of argon oxygen decarburization (AOD) slag and analyzing influence mechanism of carbonation on chromium leachability. Static thin-film accelerated carbonation and sequential leaching tests were carried out. Results show that the liquid to solid (L/S) ratio was the most influencing factor for AOD slag's carbonation, and the maximum carbonation ratio of AOD slag was 50–52% (L/S = 0.4 mL/g, P CO2 = 7.5 bar, and t > 6 h). Dicalcium silicate's carbonation resulted in the generation of amorphous calcium carbonate, crystalline calcite and silica gel. AOD slag's smooth surface could be eroded by these products gradually with carbonation furthered. The mineral phase evolution clearly influenced the mineral phase hydrolysis and physical encapsulation, and thus affected the hydrolysis behavior of the primary phase and the generation behavior of the secondary phase in the carbonated slags. Chromium leachability (20 days) declined to its lowest value (1.7 mg/kg) as the carbonation ratio growing to 23% and then increased to its highest value (7.9 mg/kg) with the carbonation ratio increasing to 52%. Chromium leachability varies with the carbonation ratio. The optimal carbonation ratio that resulting in minimum chromium leaching risk must be taken full in mind before using AOD slag in carbonation-related production activities. Image 1 • Static thin-film carbonation tests conducted on AOD Stainless Steel Slag. • Maximum carbonation ratio is 50–52% (L/S of 0.4 mL/g, P CO2 of 7.5 bar and time>6 h) • 23% carbonated AOD slag holds minimum Cr leachability. • 52% carbonated AOD slag holds a higher Cr leachability than original AOD slag. • Carbonation affects Cr leachability mainly by mineral phase hydrolysis and physical encapsulation. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.