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In this paper, we simulated and investigated microwave heating of biochar containing electric arc furnace dust spherical pellet. The influence of the distribution of components within pellet on the effectiveness of microwave heating was investigated as well as the influence of biochar conductivity. We considered the interaction of pellet with both plane wave in free space and with H10 mode wave in a single-mode waveguide. In addition, effective permittivity and permeability of EAF dust in one of the possible compositions, and of biochar – EAF dust powders mixture depending on the volume fraction of EAF dust were calculated according to effective medium approach. [ABSTRACT FROM AUTHOR]

The production of cement leads to high carbon dioxide (CO2) emission which has a negative environmental impact. So, one of the ways to minimize this issue is by the proper use of supplementary cementitious materials also known as SCMs in cement production. This review paper aims to discuss the utilization and effects of SCMs in various binding mixtures of mortar including some advantages and limitations. SCMs are used as a partial substitute for cement. This paper emphasizes the reviewed results on the effect of the SCMs like silica fume, copper slag, steel slag, fly ash, electric arc furnace dust (EAFD), ground granulated blast-furnace slag (GGBS), limestone powder, etc on properties of cement mortar and paste. The results on properties of the mortar like flowability, strength (compressive, flexural and split tensile strength) and durability are presented. Besides, parameters like mortar performance, setting time, binding strength, etc are summarized. The effects of physical and chemical properties, fineness, pozzolanic activity, etc of SCMs on properties of mortar are also discussed. Mortars in which cement is replaced by the above-mentioned SCMs comparatively showed higher compressive and flexural strength depending on the replacement ratio and the curing age. Using GGBS as an SCM has enhanced the mortar performance with elevated temperature. Even mechanical and durability properties of the mortars are found to improve for copper slag and steel slag. Thus, the available tests and their findings from different studies have been reviewed, interpreted, and summarized. [ABSTRACT FROM AUTHOR]

Accumulation of the metallurgical waste stimulates development of the recycling technologies. The paper investigates the chemical and phase composition of the particular electric arc furnace (EAF) dust which is formed in the gas cleaning system during steel smelting from scrap. It was found that the main components of the EAF dust under study are ZnFe2O4, ZnO, CaCO3, SiO2 and KCl. The XRD phase analysis showed that the prevailing phase is zinc ferrite ZnFe2O4 (62 %). The thermodynamic analysis was carried out using TERRA software. According to modeling, the iron reduction proceeds sequentially ZnFe2O4 – Fe3O4 −FeO–Fe in the temperature range from 500 to 700 °C. Above 510 °C ZnFe2O4 decomposes with formation of ZnO and Fe3O4. Zinc oxide is intensively reduced in the temperature range from 800 to 900 °C passing into the gas phase. [ABSTRACT FROM AUTHOR]

The paper considers the asymmetrical current and voltage of a single operating arc furnace, powered by a 220/35kV power transformer, included in the metallurgical enterprise system. The uneven current load of the individual phases was examined and the dynamics of the asymmetry coefficient was evaluated. The results from the studies can be used as basic prerequisites in the selection and setting of relay protection of such consumers. [ABSTRACT FROM AUTHOR]

The blast furnace slags are a by-product of the production process of cast iron, during which large amounts of liquid slags are formed. The composition of the blast furnace slags depends on the actual quality and proportion of the minerals and fluxes present in the blast furnace charge. Every year the steel industry in Europe produces 2900 tons of slags that, if left untreated, represent an industrial waste to be sent to landfills with serious environmental impact. In the RESLAG (Turning waste from steel industry into valuable low cost feedstock for energy intensive industry) project, the use of waste products deriving from iron and steel plants as new feedstock in different fields is considered: recovery of precious metals, thermal energy storage systems for steel-making and CSP industry, production of innovative refractory ceramic compounds. Within this framework, ENEA is investigating the possibility of using pebbles made with slags produced by the steel industry as a filler in high-temperature packed-bed thermocline TES systems, using a binary mixture of molten salts (60% NaNO3 40% KNO3) as HTF. More specifically, the pebbles are obtained by processing and sintering Electric Arc Furnace (EAF) slags produced during the manufacture of crude steel. Here, the lessons learned and the first experimental results collected during the commissioning phases of the PBTTES pilot plant developed within the RESLAG project are reported. In particular, the paper firstly reports about a preliminary set of tests carried out to check the chemical compatibility of the slags with the molten salts. Subsequently, the pilot plant is described and the results of the first commissioning tests, which were aimed at flooding the packed-bed with molten salts and checking the installed instrumentation, are reported. [ABSTRACT FROM AUTHOR]

In order to strengthen the competitiveness of concentrated solar power plants, the development of cost-effective storage options is indispensable. For power plants based on air receivers, the technology of direct-flow solid heat storage is an obvious choice. The heat storage inventory used is a significant cost factor for this technology. The use of slag from steel production could significantly improve the competitiveness of this technology. The ReSlag project deals with open questions on the suitability of electric arc furnace slag. This paper presents the final experimental investigations on a pilot scale for the use of sintered electric arc furnace slag in solid heat storage systems. The results of cyclic tests under different operating conditions as well as of standstill tests are presented and successfully compared with simulation results. [ABSTRACT FROM AUTHOR]

This paper presents an innovative approach of utilizing electric arc furnace (EAF) slags in value-added applications, particularly as storage media for high-temperature thermal energy storage (TES) systems, applied to next- generation of central receiver concentrated solar power (CSP) plants. EAF slag is a solid industrial waste produced in large quantities in metallurgy worldwide and commonly sent to dump sites. Due to steel slag's chemical composition of metal and non-metal oxides, advanced ceramic bodies can be prepared using thermally treated EAF slag powder. The crystallographic stability of oxidized EAF slag powder was confirmed by XRD analysis that revealed the absence of any crystal phase transformation at elevated temperatures up to 1200 °C. Advanced ceramic entirely recycled from locally UAE produced EAF slag was prepared following the method of cold compaction of ceramic powder. For sensible heat TES materials, a high density is desired to maximize the storage capacity. Therefore, the final product bulk density was examined by studying the influence of parameters such as (i) the applied compaction pressure, (ii) the firing temperature, (iii) the binder weight percentage, and (iv) the firing time. Findings showed that a compaction pressure of 186 MPa resulted in relatively dense green ceramic bodies. The firing of these bodies at 1200 °C with a dwell time of 3 hours resulted in ceramic products with a bulk density in the range of 2500 kg/m3 that could be potentially used as TES media. [ABSTRACT FROM AUTHOR]

The world's interest in the use of recycled material (by-product or secondary material) as a substitute for gravel on road constructions in the last years grows. Typical specimen is electric arc furnace slag generated as waste from steel production. It's chemical composition varies depending on the principle of a metallurgical process, batch, origin, etc. The paper deals with the evaluation of laboratory tests of electric arc furnace slag as a materials used in embankment constructions. Results of laboratory tests, that are determined by physical (Proctor modified, specific gravity determination, etc.) and mechanical properties (direct shear test, California bearing ratio test, etc.), demonstrate the potential use of slag as aggregate in geotechnical engineering. [ABSTRACT FROM AUTHOR]

Electric arc furnace (EAF) is used for smelting of recycled steel scrap. During scrap smelting, dust is emitted from the furnace due to the high temperature of the smelting process. The dust is characterized by its fine particle size and high content of heavy metals including iron, zinc, lead, and cadmium in the form of metal oxides. Therefore, this dust is considered to be hazardous waste according to the Environmental Protection Agency (EPA). Huge amounts of this dust are accumulated worldwide (5-7 million ton per year). The dust also contains considerable amounts of chlorides (mainly sodium and potassium). The presence of these chlorides may complicate the extraction of valuable metals from the EAF dust, particularly during the electrolysis process. On the other hand, huge amounts of chlorinated waste plastic materials, such as poly-vinyl chloride (PVC), which are accumulated worldwide, form another environmental waste problem. This paper primarily dealt with the leaching process, before the pyrolysis process. Water was used as leaching agent. The effects of such different parameters as pH, temperature, multi stage, contact time and solid to liquid ratio on EAF dust leacheability were considered. As conducted experimentally, it was shown that simple metal leaching reduces the load on the pyrolysis process. In addition to that, conducting leaching before pyrolysis in comparison to conducting pyrolysis on its own is shown to be more cost efficient in terms of energy output and cost of fuel needed. [ABSTRACT FROM AUTHOR]

Increasing of demand for implant material especially for hip bone is caused by the increasing of elder who are prone to osteoporosis. Several studies have reported that elements of Al and V in Ti-6Al-4V can decompose and result in adverse effects in the form of health problems, allergies, neurological disorders and Alzheimer's disease. In addition, Ti- 6Al-4V has a problem, the difference of young's modulus with human bones can cause stress shielding phenomena. The cost of replacing hip bones is quite expensive because it uses valuable alloy elements. The novelty carried out in this study was the design of a new titanium type β (beta) composition with a composition of the weight of Ti-6%Nb-6%Mo with the addition of Mn 8%, 10%, 12% and continued with heat treatment at 1100°C with variations of heat treatment time 3 hours, 6 hours and 12 hours with water quench which aims to increase beta phase volume. The material characterization was performed using XRF, XRD, metallographic test, micro Vickers hardness test and ultrasonic test to calculate the magnitude of young's modulus. The results obtained show that the addition of manganese will increase beta phase. The most optimal duration for heat treatment is 6 hours because the Ti-6Mo-6Nb microstructure with the addition of 12% manganese and heat treatment for 6 hours has higher beta phase volume than others. [ABSTRACT FROM AUTHOR]