scholarly journals CO2 mineral sequestration with the use of ground granulated blast furnace slag

2017 ◽  
Vol 33 (1) ◽  
pp. 111-124 ◽  
Author(s):  
Alicja Uliasz-Bocheńczyk ◽  
Eugeniusz Mokrzycki

Abstract The mineral sequestration using waste products is a method of reducing CO2 emissions that is particularly interesting for major emitters and producers of mineral wastes, such as iron and steel industries. The CO2 emissions from iron and steel production amounted to 6,181.07 kt in 2014 (PNIR 2016). The aforementioned industry participates in the EU emission trading system (EU ETS). However, blast furnace processes produce mineral waste - slag with a high content of CaO which can be used to reduce CO2 emissions. Metallurgical slag can be used to carry out direct (a one-step process) or indirect (two-stage process) process of mineral sequestration of carbon dioxide. The paper presents the degree of carbonation of the examined samples of granulated blast furnace slags defined by the six-digit code (10 02 01) for the waste and the respective two-digit (10 02) chapter heading, according to the Regulation of the Minister of the Environment of 9 December 2014 on the waste catalogue. The carbonation process used the direct gas-solid method. The slags were wetted on the surface and treated with CO2 for 28 days; the obtained results were compared with the analysis of fresh waste products. The analyzed slags are characterized by a high content of calcium (nearly 24%), while their theoretical binding capacity of CO2 is up to 34.1%. The X-ray diffraction (XRD) analysis of the phase composition of slags has revealed the presence of amorphous glass phase, which was confirmed with the thermogravimetric (DTA/TG) analysis. The process of mineral sequestration of CO2 has resulted in a significant amount (9.32%) of calcium carbonate - calcite, while the calculated degree of carbonation of the examined blast furnace slag is up to 39%. The high content of calcium, and a significant content of CaCO3-calcite, has confirmed the suitability of the discussed waste products to reduce carbon dioxide emissions.

2020 ◽  
Vol 39 (1) ◽  
pp. 539-544
Author(s):  
Yi-Ci Wang ◽  
Pei-Jun Liu ◽  
Guo-Ping Luo ◽  
Zhe Liu ◽  
Peng-Fei Cao

AbstractCaO–MgO–Al2O3–SiO2 glass-ceramics with diopside as the main crystalline phase were prepared by melting blast furnace slag obtained from Baotou Iron and Steel Company. The effect of heat treatment on the crystallization behavior of glass-ceramics, containing a large proportion of melted blast furnace slag, was studied by means of differential thermal analysis and scanning electron microscopy. The optimum heat-treatment regime was obtained by orthogonal experimental results for glass-ceramics in which blast furnace slag comprised 70% of the composition and 1% Cr2O3 and 4% TiO2 were used as nucleating agents. The nucleation temperature was 750°C for 2.5 h and the crystallization temperature was 930°C for 1 h. Under this regime, the performance of the glass-ceramic was better than that of other groups in the orthogonal experiment.


2018 ◽  
Vol 10 (2) ◽  
pp. 436-448 ◽  
Author(s):  
Enze Ren ◽  
Siyang Tang ◽  
Changjun Liu ◽  
Hairong Yue ◽  
Chun Li ◽  
...  

2021 ◽  
Vol 13 (20) ◽  
pp. 11298
Author(s):  
Alessio Occhicone ◽  
Mira Vukčević ◽  
Ivana Bosković ◽  
Claudio Ferone

The aluminum Bayer production process is widespread all over the world. One of the waste products of the Bayer process is a basic aluminosilicate bauxite residue called red mud. The aluminosilicate nature of red mud makes it suitable as a precursor for alkali-activated materials. In this work, red mud was mixed with different percentages of blast furnace slag and then activated by sodium silicate solution at different SiO2/Na2O ratios. Obtained samples were characterized by chemical–physical analyses and compressive strength determination. Very high values of compressive strength, up to 50 MPa, even for high percentage of red mud in the raw mixture (70 wt.% of RM in powder mixture), were obtained. In particular, the higher compressive strength was measured for cubic samples containing 50 wt.% of RM, which showed a value above 70 MPa. The obtained mixtures were characterized by no or scarce environmental impact and could be used in the construction industry as an alternative to cementitious and ceramic materials.


2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Branislava M. Lekić ◽  
Dana D. Marković ◽  
Vladana N. Rajaković-Ognjanović ◽  
Aleksandar R. Đukić ◽  
Ljubinka V. Rajaković

In this study, removal of arsenic ions using two industrial by-products as adsorbents is represented. Removal of As(III) and As(V) from water was carried out with industrial by-products: residual from the groundwater treatment process, iron-manganese oxide coated sand (IMOCS), and blast furnace slag from steel production (BFS), both inexpensive and locally available. In addition, the BFS was modified in order to minimise its deteriorating impact on the initial water quality. Kinetic and equilibrium studies were carried out using batch and fixed-bed column adsorption techniques under the conditions that are likely to occur in real water treatment systems. To evaluate the application for real groundwater treatment, the capacities of the selected materials were further compared to those exhibited by commercial sorbents, which were examined under the same experimental conditions. IMOCS was found to be a good and inexpensive sorbent for arsenic, while BFS and modified slag showed the highest affinity towards arsenic. All examined waste materials exhibited better sorption performances for As(V). The maximum sorption capacity in the batch reactor was obtained for blast furnace slag, 4040 μgAs(V)/g.


2016 ◽  
Vol 35 (3) ◽  
pp. 309-319 ◽  
Author(s):  
Yu-Lan Zhen ◽  
Guo-Hua Zhang ◽  
Kuo-Chih Chou

AbstractThe carbothermic reduction experiments were carried out for titanium-bearing blast furnace slag in Panzhihua Iron and Steel Company in argon atmosphere at high temperatures. The effects of reduction temperature, isothermal treatment time and carbon content on the formation of TiC were studied by X-ray diffraction (XRD) and scanning electron microscope (SEM). The XRD pattern results showed that MgAl2O4 phase disappeared and the main phase of the reduced sample was TiC when the reduction temperature was higher than 1,773 K. The SEM pictures showed that the reduction rate of the titanium-bearing blast furnace slag could be increased by enhancing the temperature and the C content (carbon ratio ≤1.0). Furthermore, it was also found that TiC had the tendency of concentrating around the iron. The effects of additives such as Fe and CaCl2 on the formation of TiC were also studied in the present study.


Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4103
Author(s):  
Huaqing Liu ◽  
Yan Zhang ◽  
Jialong Liu ◽  
Zixia Feng ◽  
Sen Kong

Steel bar corrosion caused by chloride was one of the main forms of concrete deterioration. The promotion of chloride binding capacity of cementitious materials would hinder the chloride transport to the surface of steel bar, thereby alleviating the corrosion and mitigating the deterioration. A comparative study on binding capacity of chloride in cement-fly ash system (C-FA) and cement-ground granulated blast furnace slag system (C-GGBS) with diethanol-isopropanolamine (DEIPA) was investigated in this study. Chloride ions was introduced by adding NaCl in paste, and the chloride binding capacity of the paste samples at 7 d and 60 d was examined. The hydration process was discussed via the testing of hydration heat and compressive strength. The hydrates in hardened paste was characterized by X-ray Diffractometry (XRD), Thermo Gravimetric Analysis (TGA), and Scanning Electron Microscope (SEM). The effect of DEIPA on dissolution of aluminate phase and compressive strength was discussed as well. These results showed that DEIPA could facilitate the hydration of C-FA and C-GGBS system, and the promotion effect was higher in C-FA than that in C-GGBS. DEIPA also increased the binding capacity of chloride in C-FA and C-GGBS systems. One reason was the increased chemical binding, because DEIPA facilitated the dissolution of aluminate to benefit the formation of Friedel’s salt. Other reasons were the increased physical binding and migration resistance. By contrast, DEIPA presented greater ability to increase chloride binding capacity in C-FA system, because DEIPA showed stronger ability to expedite the dissolution of aluminate of FA than that of GGBS, which benefited the formation of FS, thereby promoting the chemical binding. Such results would give deep insight into using DEIPA as an additive in cement-based materials.


2012 ◽  
Vol 220-223 ◽  
pp. 117-122
Author(s):  
Guo Ping Luo ◽  
Yan Ban ◽  
Yi Ci Wang ◽  
Wen Wu Yu ◽  
Qi Jiang

The mineral composition of the solidified blast furnace slag and the occurrence of special components CaF2, K2O, Na2O, RexOy and ThO2 were researched by optical microscope analysis, X-ray diffraction analysis and scanning electron microscopy and energy spectrum analysis. The results showed that the major minerals in solidified furnace slag are akermanite and gehlenite; the special component CaF2 is not hosted in the cuspidine (3CaO•2SiO2•CaF2), but in the magnesium and aluminum silicate mineral; the special components K2O,Na2O is hosted in akermanite, magnesium and aluminum silicate mineral and perovskite; the element thorium cannot form an independent mineral, but coexist with the rare earth element Ce in the perovskite. The results will lay a foundation for further study on the influence of these special components on the crystallization behavior of glass-ceramics.


2012 ◽  
Vol 15 (2) ◽  
pp. 70-80
Author(s):  
Mien Van Tran ◽  
Yen Thi Hai Nguyen ◽  
Thi Nguyen Cao

Chloride-induced corrosion of steel reinforcement is the main cause of deterioration of reinforced concrete structures in marine environments. The penetration of chlodride ions into concrete cover that accelerates corrosion process of steel reinforcement, this affects the bearing capacity of structures. This paper investigates on chloride permeability cheracteristic of concrete using blast furnace slag in terms of chloride diffusion coefficient and chloride binding capacity. The concrete used in this research has grade of 45MPa and the slag content replacement of cement PC50 is in range of 0% - 70%. The chloride diffusion coefficient of concrete is determined by ASTM C1202 and NordTest NT Build 492. Results showed that the blast furnace slag replacement increases (from 0% to 50%), the chloride ion diffusion coeffient decreases and bound chloride content in concrete increases. It is clear to conclude that blast furnace slag can be used to replace cement PC50 in range of 30% to 40% in order to increase the resistance of concrete to chloride penetration without affecting concrete strength.


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