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By M. J. Adam

The Bureau of Mines is investigating the feasibility of partitioning complex sulfide minerals to simpler sulfide phases by sulfidation reactions. Such partitioning can afford opportunity to improve selective extraction of mineral constituents of value. This report describes research involving sulfidation partitioning of byproduct chalcopyrite concentrates from Missouri lead ore processing, and a Utah chalcopyrite concentrate from Cu ore processing. Small chalcopyrite samples were sulfidized with elemental S in glass capsules sealed after evacuating and backfilling with He, by heating for 1 to 24 h at specific temperatures in the range of 250? to 500? C, extending from below to above the boiling point of S (-4450 C).

Jan 1, 1987

By J. R. Hartin

Traditionally, many of the advances in casting technology have been made by expensive and time consuming trial-and-error methodology. Modeling of the complex solidification process promises production of castings which are made "right the first time." Even though several models are available for simulation of conventional casting processes, none of them address this relatively new technology of investment cast titanium aluminides. In this paper, modification and application of a transient, three-dimensional, fully coupled fluid flow and heat transfer solidification modeling computer program to the analysis of centrifugally cast titanium aluminides is discussed. The predictive results of the program are compared to qualities of actual cast parts for validation.

Jan 1, 1992

By Jiu-ju Cai, Wen-chao Liu, Fei Liu

"The material flow of urban eco-industrial system includes linear flow, recycling flow, branching flow, converging flow, etc., which consequently lead to the system complexity. Comparing the urban eco-industrial system to ecosystem, it can be concluded that this complexity is caused by the system adaptability. In the system, the interaction and adaptability between the agents themselves and between the agents and the environment stimulates the changes of material-flow mode, which lead to the evolvement from traditional industry to the eco-industry. Focusing on the evaluation of this evolvement process, two material-flow models are established in this paper, one of which is for the system itself and the other for the agents in system. The latter model is applied to analyze the interrelationships among mass, energy and pollutant flow in the iron and steel industry, and to make the direction clear to improve the resource and energy efficiency and decrease the environmental load.1 IntroductionIndustrial system is a subsystem of urban system, and they are interconnected and interrelated through material flow. The industrial development causes the urbanization. But the traditional industrial mode, characterized by high consumption, high pollution and low efficiency, also causes the “urban problems”, and leads to the reduction of resources carrying capacity and the increase of environmental load. Nowadays a lot of researches focus on how to realize the sustainable development of industries and cities. Thus comes the urban eco-industrial system guided by industrial ecology.Regarded as a Complex Adaptive System (CAS), the urban eco-industrial system evolves for quite a long time. According to Holland’s description on CAS, CAS consists of adaptive agents, which interact with the environment and other agents, learn and accumulate experiences, and accordingly change their own structures and motion modes. In this way, the evolution of the whole macro system is improved [1]. The evolution from traditional industrial system to urban eco-industrial system is mainly reflected in the variety of internal material flows which include not only linear flows but also recycling flows. Therefore, to construct models which clearly analyze industrial metabolism, is of great importance to evaluate industrial system evolution.The article is organized as follows: Section 2 describes the urban eco-industrial system. Section 3 presents the system-oriented metabolic analysis model and the agent-oriented one, analyze the interrelations of energy flow, material flow and pollutant flow in Chinese iron and steel industry through the latter model, and indicates the directions of improving the resource efficiency and energy efficiency, and decreasing the environmental load. Section 4 concludes."

Jan 1, 2008

By Y. Suzuki, J. Nagao, Y. Ueda, K. Shimokawa

"A Ti- Ni intermetallic compound could be formed rapidly from Ti and Ni powder compact with SHS process. Microgravity experiments using a drop shaft are carried out, This report shows the effect of microgravity or high gravity on formability of an intermetallic compound. It is concluded that the specimen forms a porous and nearly amorphous alloy by rapid cooling under microgravity but with rapid cooling under high gravity after microgravity, the specimen forms a uniform and dense structure with better crystallinity.IntroductionTi - Ni inter1etallic co1pounds have been produced and have beco1e si1ilar to the a1orphous and porous structure as a result of the SHS (Self Propagating High-te1perature Synthesis) process under 1icrogravity. SHS process is being applied to the synthesis of cera1ics and inter1etallic co1pounds (1). The technique is characterized by a large a1ount of heat being emitted within a very short ti1e interval as regards the sistering reaction. One SHS process, acco1panying 1elting by a reaction was observed, and that was due to the quick heating of a Ni-Ti co1pact containing 50 ato1ic percent of Ti under a low pressure (2-4). In this report, we have researched the use a drop shaft which is 1ore effective during a short ti1e under 1icrogravity and high-gravity, so as to obtain high dense speci1ens with the exception of porous specimens (5). Mechanical properties of each specimen were esti1ated from these 1icro-structures with a discussion about the effect of changing gravity regarding 1elting and solidification of the Ti-Ni intermetallic comounds."

Jan 1, 1996

By Shengli Wu, Jiacong Zhang, Mingyin Kou, Bingjie Wen, Heng Zhou

The COREX process, which is considered to be able to replace the blast furnace, still has some gaps to reach the designed productivity. The metallization degree is regarded as one of the limitations of the COREX process. In the present work, several parameters affecting the metallization degree of direct reduced iron (DRI) are analysed by SPSS software (Statistical Product and Service Solution). Melting rate, oxidation degree of reducing gas, oxidation degree of top gas, top gas consumption per ton of burden, temperature of reducing gas, and burden distribution index are con firmed as the main factors affecting metallization degree. Based on this, a linear equation has been developed for predicting metallization degree. Additionally, improving the melter gasi fier vault temperature appropriately, increasing the proportion of high volatile matter coal, and optimizing the type and particle size of iron ore and the pattern of burden distribution have been shown to improve the metallization degree.

Mar 1, 2018

By David T. Hobbs

Large quantities of highly alkaline, radioactive, liquid wastes are stored in underground tanks throughout the Department of Energy complex. These wastes will be pretreated to separate radionuclides and the remaining decontaminated liquid wastes incorporated into solid waste forms for permanent disposal. Significant savings in disposal costs could result by recovering .the sodium as sodium hydroxide for reuse or disposal as nonradioactive waste. Recent testing demonstrated an electrochemical separation process for the recovery of sodium hydroxide from alkaline waste solutions; The separation process uses ion-selective membranes to separate sodium from the bulk of the waste constituents under an applied electrical field. The sodium is recovered as a 10-15 wt % solution of sodium hydroxide. Results of bench-sc3Ie and pilot-scale tests with simulated and radioactive waste solutions are presented.

Jan 1, 1999

By Pan Gu, Zhen Zhang, Jiang Diao, Bing Xie, Hongyi Li

Furnace refractories are in most cases chemically incompatible with smelter slag, which leads to a steady erosion in their thickness over time. Once too thin, refractory walls become mechanically unstable and catastrophic failure can result. Historically, external shell cooling was applied to generate a freeze lining of slag and thus prevent refractory erosion. Many modern high intensity smelting furnaces instead maintain their physical integrity by the use of internally cooled wall panels, plates or finger coolers. An initial refractory lining is often installed inside of the coolers, such that the furnace originally operates with a temperature (insulated) rather than a heat flux (freeze lined) boundary condition. This paper examines the change in slag-wall heat transfer coefficient and slag superheat as a function of process intensity. The implications of the changes in heat transfer on residual brick thickness are explored using analytical modelling.

Jan 1, 2016

By Guojun Qi

This work relates to wafer bumping technologies for flip chip packaging applications in the electronics industry. Nickel and its alloys are alternative under bump metallization (UBM) materials because of their slower reaction rates with Sn-based solder as compared to Cu-based UBMs. In this study, we compared the morphologies of the intermetallic compounds (IMC) formed between Sn-bearing solders (Sn3.5Ag and eutectic Sn-Pb) and two types of nickel- based UBMs, electroless Ni-P (EN) and sputtered nickel. Both chunky-type and needle-type of intermetallics were observed between the EN UBM and the solders. In the case of sputtered Ni UBM, there is only a layer of scallop-type intermetallics formed. The morphology change and growth kinetics of the IMC in thermal aging process were analysed. Kirkendall voids were noticed from samples of Sn3.5Ag solder vs Ni-P UBM that have undergone prolonged thermal aging at high temperature.

Jan 1, 2003

By Tianzu Yang, Weifeng Liu, Lin Chen, Wei Chen, DUCHAO ZHANG, HUI XIAO

Carbonaceous refractory materials are widely accepted in many reducing smelting processes such as iron and ferroalloys. Oxidizing processes such as copper concentrate smelting traditionally use magnesia and/or alumina/silica refractory materials. The main objection to the use of carbon-based refractories as the exposed working lining in oxidizing applications is the potential for free oxygen to react with the carbon at high temperature, which could rapidly degrade the refractory lining. In 2013, Outotec and GrafTech conducted joint trials of a thermally conductive, carbonaceous lining for smelting copper concentrates in the Outotec® pilot-scale top-submerged-lance (TSL) furnace in Dandenong, Australia. This testwork had two equally important goals; to demonstrate the ability of carbon refractories to withstand oxidizing process conditions, while ensuring that neither furnace operating conditions nor process stability were negatively affected by the refractory material. The paper discusses the input parameters of the trials, key observations during the testwork program, and the results and conclusions from both process and refractory design standpoints.

Jan 1, 2016

By Hong Yong Sohn

A novel flash ironmaking technology is under development at the University of Utah under the support of U.S. Department of Energy (DOE) and American Iron and Steel Institute (AISI). The history of the development from the conception of the idea to the current status will be discussed. The flash ironmaking process produces iron directly from fine iron ore concentrates without requiring cokemaking and pelletization/sintering, which will enable the technology to significantly reduce energy consumption and carbon dioxide emissions compared with blast furnace ironmaking. Unlike other gas-based ironmaking processes, this technology will not suffer from the problems of solid sticking and fusion. Current work is focused on the method of supplying the energy required to maintain the necessary temperature, as an intermediate step to determine the scalability for larger, industrial-scale pilot trials.

Jan 1, 2014

By Xin Zhang, Mengqi Li, Hongxu Li, Xinrong Zhang, Hao Bai, Ning Li

"Organic Rankin Cycle (ORC) is an effective technology to transform low-grade energy resource into electricity. In this paper, based on thermodynamic principle, considering the waste heat resource lower than 120°C, thermodynamic properties of ORC with working fluids ofR245fa, mixed R21/R245fa and mixed Rl52a/R245fa were assessed. The results show that high evaporation temperature contributes to improved system performance. The Rankine Cycle that uses R21/R245fa can increase net cycle output, thermal efficiency and exergy efficiency by 3.02%, 2.35%, and 4.44%,respectively, as compared to that with pure R245fa. When using Rl52a/R245fa as working fluid, the net cycle output can increase by 3.83% at most, while the thermal efficiency decreases by 8.7%. These results indicate that R21/R245fa has a good advantage in improving the cycle thermodynamic performance.IntroductionOrganic Rankine cycle is usually used for low temperature power generation, and is applied to the conversion of geothermal energy, low-temperature solar energy, ocean thermal energy and industrial low-temperature waste heat etc. Traditional Rankine cycle is quite mature already, however, organic working fluids would affect significantly the general efficiency of the entire thermodynamic system. Thus, selection of proper working fluids and development of new highperformance cycle is becoming important."

Jan 1, 2013

By C. Takano

The integrated iron and steelmaking industry generates large amounts and many types of solid dusts and sludge, at different phases of the production. Within these are: sludge of the Blast Furnace; coke fines; fine and coarse fractions from oxygen converters; sludge from water treatment at rolling mill unit; and others. In this paper the above dusts and sludge were physically and chemically characterized. The obtained results allowed defining self-reducing pellets using these materials. The high temperature behavior of the pellets were evaluated. Good results, with no decrepitation and swelling, and high yield of reduction, show that it is feasible to recycle them, as self-reducing pellets, in oxygen steelmaking converter.

Jan 1, 2001

By Shusen Cheng, Kun Yan

An elastic-plastic stress mathematical model of hot blast stove shell has been established in order to investigate the stress distribution and deformation of the shell. The results show that stress concentration happens along the intersection line of hot blast stove body and the hot blast manifold. The plastic deformation occurs on the hot blast outlet in blast period. The deformation degree of the hot blast shell near the blast outlet in blast period is much larger than that in combustion period. In blast period, the shell near the blast outlet elongates along the horizontal direction and shortens along the vertical direction, the shell near the outlet deforms into an oval. And in combustion period, its deformation isn’t obvious. The repeated deformation of the shell near the outlet between different periods may cause the refractory brick damage and be harmful to the long campaign life of hot blast stove.

Mar 1, 2017

By C. J. Parradies

During injection into a die, semi-solid metal alloys exhibit a shear-rate, history-dependent flow response. Simulating the injection of a thixotropic material requires that empirically determined boundary conditions and viscosity are specified as a function of both temperature and shear rate history. Experiments were performed using an industrial die casting machine that was instrumented with sensors to measure the pressure and temperature during the injection of a semi-solid aluminum alloy through a tube. This benchmark experiment was used to develop a simulation of the die casting process that could then be applied to more complex die geometries. The results of the experiments were analyzed using the exact, steady state solution for a power law fluid and simulations accounting for slipping at the boundary between the semi-solid metal and the die. Results indicated that the no-slip condition cannot be used to simulate the velocity boundary condition, because the measured pressure is much lower than that predicted by the models. An estimated apparent slip coefficient was introduced to account for the reduced pressure. During some of the experiments, a sudden drop in the measured pressured, prior to decreasing the ram velocity, coincided with observations of segregation in the form of concentric rings visible on the polished surface of cross-sections cut from material remaining in the tube.

Jan 1, 1997

By Onuralp Yucel, Osman Halil Celik, Hakan Morcali

In this study, some experiments were performed for the dimensional control, pre-treatment, getting salt, metallic aluminum and aluminum oxide into the solution of 15 kg aluminum black dross obtained from a private company which recycles aluminium drosses. Water leaching experiments are done for removing salts and aluminum nitride. Temperature stirring speed, solid-liquid rate are investigated while water leaching experiments. Removing of AlN is provided at 25 °C at a rate of 42.48%, at 80 °C at a rate of 86.4%. Leaching experiments performed with NaOH. NaOH concentration and time was analyzed. Efficiency of including metallic aluminum into the solution is determined to be 98% approximately. Melting (fusion) experiments were performed with NaOH at high temperatures to include aluminum oxide in the structure of the remaining after dissolving process into the solution and after dissolving the resulting structures in water, efficiency of including aluminum into the solution is determined to be 85%.

Mar 1, 2018

By S. N. Monteiro, E. B. Zanelato, J. Alexandre, M. T. Marvila, A. R. G. Azevedo, G. C. Xavier

The incorporation of industrial waste into ceramic tiles is a major trend in the search for alternative raw materials, and also in the search for environmentally correct disposal of waste. In order to evaluate the effect of the incorporation of residues from the ornamental stone industries, in the properties of ceramic tiles, incorporations of up to 40% by weight of the residue in ceramic mass were studied. It is noteworthy that this residue is constituted basically by limestone and its characterization was performed by grain size analysis, Atterberg boundaries, grain density and chemical analysis by X-ray fluorescence. The specimens were burned at 800 °C and the following properties were evaluated: linear retraction, water absorption and bending rupture stress. The results indicated that the residue of ornamental rocks is a material with potential to be used as a component in the mass of red ceramic tiles.

Mar 1, 2018

By Teuku A. R. Putra, Patrick R. Taylor

Various pyrometallurgical methods for treating copper concentrates that contain appreciable arsenic are reviewed. Various aspects of the engineering of these treatment methods are discussed. The methods discussed include: complete oxidation with arsenic fixation; selective volatilization of arsenic; acid baking, soda ash roasting, and others methods. Methods for the ultimate disposal, or marketing, of the arsenic are discussed.

Jan 1, 2014

By Florian Kongoli

"Lime ferrite" slag with limited silica content has proven to be a valuable choice in the modem processes of copper smelting and converting due to several advantages that this slag offers compared to classical silicate slags. Nevertheless the liquidus surface of this slag has been experimentally measured only at low oxygen potentials such as in equilibrium with iron or hear it and in air. Although most of the smelting and converting processes that use this slag occur at intermediate oxygen potentials, the liquidus surface of this slag is not known at these conditions and the effect of oxygen potential and silica has not been correctly understood. This has brought some confusion in literature as well as in the industrial practice. In this work the liquidus surface of the calcium ferrite slags has been quantified by the means of a new thermophysicochemical model and a new type of liquidus surface diagrams which are very convenient for any industrial process that uses calcium ferrite slags. These diagrams can be easily used to select the lowest liquidus temperature of calcium ferrite slags at a minimum cost and can help design several fluxing strategies in copper smelting and converting processes. The effect of the oxygen potential and silica is also quantified and important industrially related conclusions are drawn.

Jan 1, 2003

By Dachun Liu, Xutao Guo, Wenlong Jiang, Baoqiang Xu, Bin Yang, Yong Deng, Heng Xiong

Typical copper dross, the byproduct of lead bullion pyrometallurgical refining for copper removal, mainly contains Pb, Cu, S, As, Sb and Sn etc. In traditional treatment process, copper dross is transformed to be copper matte by smelting with iron scarp and iron pyrite. Here, a new treatment process of converting-vacuum distillation (CVD) was proposed and investigated. Based on this concept, the converting process was tentatively investigated in this paper. The results of element distribution of converting samples showed the sample has three layers. The upper layer is mainly sulfides of lead and copper, the middle layer is mainly copper arsenide, and the lower layer is lead arsenide and crude lead. On the condition of oxygen flow rate 400 ml/min, the converting temperature 1000 °C, the holding time 1 h, the converting time 10 min, the lead copper alloy containing 0.17% S was obtained.

Mar 1, 2018

By Yinlun Huang, Cristina Piluso

"Industrial sustainability looks to improve material and energy efficiencies, product quality and variety, and productivity within an industrial zone, thus pursuing the long-term sustainable development of the region. This paper introduces a systems-based modeling methodology, which provides industrial leaders with the ability to evaluate future production options to determine the path with the highest positive impact on both their own sustainability and the sustainability of the overall industrial zone. A comprehensive study on sustainable development of an auto-manufacturing focused industrial zone under uncertainty is illustrated. Introduction Sustainable development refers to a continuous process of improvements that must be followed in order to achieve a state of sustainability. In its most general form, a widely accepted definition of sustainable development was identified in the Brundtland Report as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs” [1]. Sustainability will occur when the material and social conditions can be maintained or improved for human health and the environment over time without exceeding the ecological capabilities that support them [2]. An industrial zone is defined as a geographic area comprised of a network of industrial sectors, each composed of a number of entities. Such a zone is highly integrated and complex, and contains numerous uncertainties due to each industry’s extreme dependencies on its suppliers and customers throughout the product supply chain. In the context of an industrial zone, sustainable development refers to the continuous process of advancements in the zone, and the entities that comprise it, creating more value, wealth, and profits (economically viable dimension), providing environmentally benign products with less raw material consumption and waste generation (environmentally compatible dimension), and collaboration and a direct relationship among all involved in the supply chain, i.e. the corporations, employees, suppliers, investors, communities, customers, etc. (socially responsible dimension). These are the triple bottom lines of industrial sustainability. In order for economic, environmental, and social sustainability improvements to be successfully implemented within an industrial zone, the industrial decision makers must possess system-wide analysis abilities. The analysis of the sustainable development of an industrial zone involves decisions at the local, regional, or national levels, which are complex and involves handling of ill-defined parameters with a high degree of uncertainty due to the imperfect understanding of the underlying issues [3]. This work focuses strictly on the uncertainties in future zone planning and a method and a scenario based approach that can be used to evaluate the sustainable development of an industrial zone among these uncertainties."

Jan 1, 2008