Papers by Keyword: Steel Slag

Abstract: Industrial emissions used as admixture in foam concrete not only save resources, but also improve the properties of foam concrete. In this paper the thermal properties of steel slag fly ash foamed concrete was studied through experiments, and the results were analyzed. This paper included several of them and validated them using test dates, compared the results with other researchers. The result is the general model can predict the thermal conductivity of foam concrete better. Maxwell-Eucken model can regard as the boundaries’ formula to predict the coefficient of thermal conductivity of foam concrete and determine the limits. For the same density with the increasing of the steel slag thermal conductivity increases, specific heat decreases. The porosity is linear to the density of foam concrete.

Abstract: Different techniques were used to characterise BOF slag. The main mineral phases of steel slag are dicalcium silicate C₂S , trecalcium silicate C₃S and dicalcium ferrite C₂F, and C₄AF. Some minor phases as ferrite oxides (FeO,Fe₂O₃) were also identified. The cementitious test indicated that strength of mortar decreased with the increasing of steel slag replacement, and the sample with finer steel slag tends to gain higher strength. Steel slag exhibited significant adverse effect on the early strength, but benefited at late ages.

Abstract: This article presents the results of an experimental research dealing with the use of steel slag as a partial substitute for natural aggregates in the production of concrete composite. Comparative mixture based on natural aggregates was prepared from the fractions of 0/4, 4/8 and 8/16 mm, which were represented in the volume ratio of 40:30:30. During the experimental research, natural aggregates with the fractions of 4/8 mm, 8/16 mm were replaced with steel slag of the same faction. We have tested the input properties of natural aggregates and steel slag for the designed experimental mixtures (grain size, density, specific weight, powder density, absorption capacity, resistance to crushing, shape index). In case of concrete mixture prepared according to the experimental recipes, we have monitored the following characteristics: density of fresh concrete mixture, consistency of concrete mixture, strength characteristics - cube strength after 3, 7, 14, 21, 28 and 90 days, prism strength after 28 days. The research has discovered that substitution of natural aggregates with steel slag of the same fraction in concrete mixture is possible, without significantly affecting the strength properties of the concrete based on steel slag in comparison with the concrete based on natural aggregates.

Abstract: A new method to make SMA is developed by using SBS modified asphalt when the coarse aggregate steel slag and the fine basalt aggregate are selected respectively. The Mix Proportion is 1#(16-9.5mm, steel slag):2#(9.5-4.75mm, steel slag):3#(3-4.75mm, basalt):4#(3-0mm, basalt):5# (mineral powder)=38%:36%:8%:8%:10%.The optimal asphalt content (OAC) is 6.4%. The mass percentage of steel slag is reached 74%. The costs of this kind of high quality road material can be saved because the amount of asphalt is not increased. Based on Marshall Stability and Splitting Strength test, it is shown that the Marshall stability of SMA is 10.6 kN, dynamic stability is 7800, and tensile strength ratio is 89.2%. All above test values are superior to the standards in China's traffic regulations. The water permeability coefficient of SMA is 65, which means that SMA has an excellence Wear-Resistant performance. Therefore, SMA can increase the road useful life and reduce the road maintenance costs.

Abstract: ABSTRACTAluminium alloys are used in advanced applications because their combination of high strength, low density, and durability. However, the properties of this material can be improved by using aluminium matrix composite materials. By reinforcing hard ceramic particles like SiC, Al₂O₃and B₄C, TiO₂ etc the strength of the composite can be enhanced. In this paper an effort is made to enhance the property of AMCs by reinforcing steel slag particle with A356 matrix. By varying the weight percentage of the steel slag the composite material was prepared through stir casting method. The mechanical property like hardness and impact strength of A356 was investigated and compared with that of composite material. The result reveals that by increasing the reinforcement percentage of steel slag the impact strength decreases with the increase in hardness of the composite material. The density is also compared with that of A356 composite.

Abstract: This article reports on the possibilities of using selected alternative materials like hemp fibres, MgO-cement, recycled concrete, fly ash and steel slag as binder or filler replacement in composite materials in civil engineering production. These binder or filler substitutes were mixed into composites and their compressive strength was tested. The paper is divided into four parts providing the results of experiments. In first part strength parameters of lightweight composites based on natural fibres (hemp hurds) and alternative binder (MgO-cement) are presented. Compressive strength values of concrete samples with partial replacement of cement with mechanochemically activated coal fly ash are given. The third and forth part is aimed to utilization of recycled concrete and steel slag as a natural aggregate replacement in concrete mixture for purpose of structural concrete and surface roads.

Abstract: Steel slag waste is a by-product of steel mining industry. Effort to utilize the steel slag in concrete production has been failed due to its high contents of MgO which causes volumetric instability of the hardened concrete. Researchers also have failed to utilize the steel slag in the sub-base of road construction due to its low compaction ratio. Geopolymer concrete is a new sustainable material made of mainly two materials which are alkali liquid and source material. The source material usually has to be pozzolanic. However, the chemical composition of the steel slag has shown that the steel slag is not considered as a pozzolanic in accordance to the requirement of the ASTM. Therefore, a special modification has been carried on and a geopolymer steel slag brick has been developed. The new developed geopolymer steel slag brick has compressive strength of about 10 MPa which is made the brick suitable for construction of a load bearing walls.

Abstract: When steel slag, a by-product of steel making in impurity catching process, is added, the forming process of cement clinker and the major reactions in that process are changed. Since there are dramatic differences between the chemical components and mineral compositions of steel slag and that of natural cement raw materials, the empirical equation for the calculating forming heats of cement clinker made of limestone and clay is no longer applied for those made of steel slag. In this paper, the empirical equation for forming heat calculation of steel slag added cement clinker was promoted, and testified by acid dissolution experiments. Results showed that the change of raw materials had great influence on the forming heat of cement clinker. When the traditional raw materials were replaced with steel slag, the forming heat of cement clinker reduced. Calculating the forming heat by our revised empirical equation can help reduce errors and bring great convenience for the calculation and evaluation of heat efficiency. This research provides theoretical underpinning for the study and calculation of forming heat of steel slag added cement clinker.

Abstract: Steel slag, a kind ofindustrial residues, is generated in the process of steel-making. Paper sludgeis the final material which origins from the treatment of liquid waste. Allthese resulted in a serious pollution of environment, how to achieve thecoordinate development among enterprise, environment and society become apressing matter of the moment. Based on this, Circular economy becomenecessary. Based on circular economy, the two kinds of industrial wastes weremixed to manufacture useful materials through carbonation in this research. Therequired raw materials were mixed by mortar mixer at the specified mixingratio. Then the mixture was transferred to a stainless steel mould formanufacturing of rectangular composite specimens. Only in this way, It is toshift from the paper maunfacturing and ironmaking and steelmaking industrywhich is over-consumption of energy and natural resources and very seriousenvironmental pollution to the industry which is less pollution and thedevelopment of multi-part cycle.

Abstract: Carbon dioxide emission and industrial waste recycling have become hot spots of the world's scientific research, and the preparation of brick in CO₂ mineral carbonation of steel slag increased gradually. However, there still exists some questions, such as low strength, low carbonization efficiency. Combined with these problems and according to the previous experimental basis, this study aims to further improve the carbonation efficiency and mechanical properties of building materials. In this paper, it studied the influence of carbonization pressure in the preparation of steel slag bricks as building materials by CO₂ mineral carbonation. The results show that the optimal carbonization pressure is about 0.25MPa. Under the process parameters, the carbonization efficiency and the compressive strength is 16.6% and 65.1MPa respectively.