Deriving Value from Challenging Waste Materials: Recycling and Sustainability Joint Session: Poster Session
Sponsored by: TMS Extraction and Processing Division, TMS Light Metals Division, REWAS Organizing Committee, TMS: Energy Committee, TMS: Recycling and Environmental Technologies Committee
Program Organizers: John Howarter, Purdue University; Elsa Olivetti, Massachusetts Institute of Technology; Mingming Zhang, ArcelorMittal Global R&D; Randolph Kirchain, Massachusetts Institute of Technology; Henry Colorado, Universidad de Antioquia
Monday 6:00 PM
February 27, 2017
Room: Hall B1
Location: San Diego Convention Ctr
D-10: Indium Extraction of Obsolete LCD Screen: Gabrielle Jimenez1; Viviane Moraes1; Jorge Tenório1; Denise Espinosa1; 1USP
The LCD screens (liquid crystal display) are composed of ceramic, metallic and polymeric materials, and are present in most consumer electronics devices such as mobile computers and televisions. Due to the turnover of electronics demand of such waste has grown exponentially. The aim of this research is to define hydrometallurgical routes to solid-liquid extraction and liquid-liquid of the indium present in LCD waste. The indium is found in form of ITO (indium tin oxide). This route involves the extraction of leaching in an acid (sulfuric acid, nitric acid and aqua regia), which was in different concentrations. The control parameters for extraction temperature were 50°C to 90°C and the time was 1 to 4 hours.
D-11: Alternative Method for Materials Separation from Crystalline Silicon Photovoltaic Modules: Pedro Forastieri de Almeida Prado1; Jorge Alberto Soares Tenório1; Denise Crocce Romano Espinosa1; 1University of São Paulo
There has been an increasing push to develop environmentally sound recycling processes of electronic waste (WEEE), including end-of-life photovoltaic modules, to reclaim materials such as silver which is both valuable and pollutant to human health and wildlife. However, process sustainability and economic feasibility of PV panels recycling is strongly tied to the materials separation step, which currently presents challenges due to use of high temperature treatments and strongly acidic solutions. A method using an easily accessible solvent - isopropanol - dissolved the silicone-based encapsulant of crystalline silicon PV modules in 2 days at room temperature, separating the module into semiconductor wafer, glass, ribbon and backsheet.
D-12: Calcium Aluminate Cement Paste Blended with Steel Slag: John Zapata1; Alexandra Loaiza1; Henry Colorado1; 1Universidad de Antioquia
The addition of steel waste in the form of slags and dust to cement is beneficial to the environment because waste can be immobilized, and thus, decreasing the waters contamination. In this investigation two different formulations of calcium aluminate cement (CAC) pastes, with 51 and 71% of alumina contents, have been combined with 0, 1, 5, 10, and 20wt% of steel slag. The water to cement ratio (W/C) used was 0.4. Both the raw cement powders and their corresponding samples after hydration were characterized in their microstructure by scanning electron microscopy, X-ray diffraction, granulometry, x-ray fluorescence, density, and compression tests.
D-13: Structure-Property Relation Of Asphalt Blended With Electric Arc Furnace Dust (EAFD): Yailuth Loaiza Lopera1; Sergio Cifuentes1; Henry Colorado Lopera1; 1Universidad de Antioquia
This investigation is about the development ofasphalt blended with Electric Arc Furnace Dust (EAFD) generated as byproduct from the steelmaking industry in Colombia. EAFD is considered a hazardous waste due to its heavy metal high contents. Five mixtures of asphalt with 0, 1, 5, 10, and 20wt% of EAFD were fabricated using a mechanical mixer. Microstructure and particle distribution was evaluated by optical, and scanning electron microscopies. Penetration, softening point, and viscosity tests were conducted over all compositions. Results show a good powder distribution in the asphalt matrix. Penetration point increases up to 10wt% of waste and then decreases. Complementarily, softening point decreases after 5wt% having a minimum in 10wt%.
D-14: Preparation Study of Ceramic Materials with Red Mud and Flying Ash as Raw Materials: Chen Shichao1; 1Beijing Shenwu Environment & Energy Technology Co.,Ltd.
Red mud is a by-product in the production of alumina, and is the most large number of solid waste in Non-ferrous metallurgical industry. China is the world's second largest producer of alumina, the annual emissions of red mud reach to millions of tons. The low efficiency of utilization of red mud has brought enormous environmental pressure to China。Therefore, how to use of red mud has received extensive attention. The feasibility of preparing ceramic using red mud and flying ash as main raw materials was investigated. The influences of roasting temperature, roasting time, material composition, forming pressure and other factors on the compressive strength and bending strength of sintered product were discussed. The research results indicates that it is feasible to prepare ceramic materials with red mud and fly ash as the main raw materials, and the product completely meets the requirements of Chinese national standard (GB/T4100-2006).
D-15: Research on Optimization of Sintering Mixture with Low-grade Complex Ore: Yutsuan Ding1; Zizong Zhu1; Zhiqiang Zhou1; Hao Xiong1; 1College of Material Science and Engineering, Chongqing University
In order to utilize the lean ore resources from XinJiang rationally and optimize mixture, laborarory measurements have been carried out under different basicity, various mixed carbon content as well as the properties(ratio) of fuel particle size by the sintering pot for further microstructure analyses. The results show that sinter strength falls by 5.0%, low temperature reduction disintegration index(RDI) drops off to the lowest in certain ranges. The natural degradation index of sinter is much higher when sinter basicity is between 1.65 and 1.75. The sinter strength increases when sinter basicity is between 1.75 and 2.0. Meanwhile, the sinter strength and RDI+3.15 improve with increasing carbon content. And the sinter strength and RDI+3.15 both decreases with the decrease of the distribution ratio of small fuel particle, thereby decreases the yield of sinter. Microstructural analyses have been investigated to figure out the mechanism of the influence of the three factors on sinter.
D-16: Bioleaching Process for Metal Recovery from Waste Materials: Solange Utimura1; Carlos Rosario1; Jorge Tenório1; Denise Espinosa1; 1University of São Paulo
The recycle of waste materials is interesting in the environmental aspect to reduce the amount of waste in landfill and to recover materials once it is represents a potential source of valuable metals. E-waste is a fast growing waste stream with complex composition. The printed wired boards (PWBs) are found in the most of the e-waste and the composite materials are ceramic, polymers and metals. The recycling of PWBs from discarded printers is an important aim to recover metals. Biohydrometallurgical is a process that may offer possibilities to recover metals from E-waste. This study evaluated the bioleaching of metals from PWBs using strains bacteria and consortium of bacteria from acid mine drainage (AMD). The bioleaching tests were performed in shake flasks at a temperature 30 °C and 170 rpm using PWBs from discarded printers in contact with bacteria. Metals concentration was determined by energy dispersive X-ray Fluorescence (XRF).
D-17: The Characterization of Hydrotalcite-like Compounds Derived from Blast Furnace Slag : Synthesis, Flame Retardancy: Jian Peng1; Hongwei Guo1; Kang Wan1; Peng Li1; Bingji Yan1; Jinyue Wang1; 1Soochow University
This study explores the potential application of blast furnace slag(BFS) for synthesizing hydrotalcite-like compounds. The CaMgAl-HTLcs were synthesized and characterized by XRD, SEM, BET and laser particle size analyzer. The altered parameters (pH value, titration way and sonication) were investigated to optimise the synthesis procedures. The CaMgAl-HTLcs was incorporated in the cotton textiles to improve its thermal stability. Thermal properties and flame retardancy of the composites were studied by thermogravimetric analysis, differential scanning calorimetry. The thermal degradation results showed that the addition of 6 wt% of the CaMgAl-HTLcs resulted in a substantial increase in the thermal stability and a reduction of the heat release rate, heat release capacity and total heat release.
D-19: Study on Adsorption Performance of Ammonia by Zeolite Synthesized from Blast Furnace Slag: Lizheng Tang1; Hongwei Guo2; Kang Wan2; Peng Li3; Bingji Yan2; Jinyue Wang2; 1University of Science and Technology of Beijing; 2Soochow University; 3Soochow university
The feasibility of synthesizing zeolite by hydrothermal method,usingthe blast furnace slag as raw material was studied. The synthesis product was characterized by means of XRD,FTIR,SEM,TEM and BET. The zeolite made from blast furnace slag was A-type zeolite ,and the specific surface area of zeolite particle was more than 150m2/g,and its average pore size was about 1nm.The zeolite derived from blast furnace slag was used as a low cost adsorbent for ammonia removal from aqueous solution. We explored the influence of pH, initial ammonia concentration,the dosage of zeolite and the adsorption time on the adsorption kinetics. As the results of the batch adsorption experiment showed, the optimal dosage of the zeolite was 2g/L ,and the adsorption equilibrium could be reached in 30 min, and the highest removal rate could be over 90% .The adsorption kinetic was fit in pseudo-second order kinetic model.
D-18: Preparing Ferrosilicon Alloy with Copper Slag: Ruirui Wei1; 1Chongqing University
Copper slag is a by-product obtained during smelting of copper from copper ores. In China, for one ton of metal production about 2.2 tons of copper slag has generated, and approximately 15 million tons slag is produced in 2013. Dumping and disposal of such huge quantities of slag will cause environmental and space problems. Most importantly, copper slag can not be made full use of to maximize its value. In this research, copper slag is used as the main material to take the place of scrap iron and part of silica in traditional process. Utilizing silica and copper slag from Jinchuan corporation as the main materials and coke as reducing agent, FeSi45 is produced in induction furnace. In addition, the effect of different carbon content on FeSi45 has been investigated，showing that silicon content tends to increase with increasing carbon content.
D-20: Chemical Analysis of Sludge Originating from Industrial Painting Performed in Brazil: Rita Alvarenga1; Henrique Santos1; Beatryz Mendes1; 1Universidade Federal de Viçosa
Inadequate discard of industrial solid waste is a risk to human health and to the environment. For softening environmental damage caused by deposition on soil of an ink residue, from washing of printers used in carton box packages, it’s intended to incorporate this residue into soil-cement bricks. However, to explore the waste’s potentialities it’s fundamental to assess the risks that this form of use of residue can cause. For such, in this work the chemical analysis of the waste was performed in order to know the main chemical compounds and leaching and solubilization characteristics. The chemical composition test showed traces of some heavy metals, although the residue-generating company uses ink labeled as heavy metals free. Some of the elements analyzed in leaching and solubilization showed a concentration above the limit allowed by The Brazilian Codes. Therefore, it’s suggested the residue has a limited use to avoid contamination of ground water.
D-21: Removal of Magnesium from Liquor Produced by Nickel Mining by Crystallization: Kristine Wanderley1; Jorge Tenório1; 1University of São Paulo (USP)
Mining of nickel ores generates large volumes of waste that must be removed in order to eliminate water contamination and reduce environmental impacts created by waste barriers. In this context, the need for innovations concerning the recovery of magnesium present in the liquor produced by the leaching of nickel laterite with sulfuric acid arises. Therefore, this work aims to develop a study regarding the crystallization of magnesium from a synthetic liquor solution using a batch autoclave system at high temperature. Agitation speed was kept constant at 1000 rpm throughout the 3 hours of batch reaction for temperatures of 230 °C and 200 °C. Aliquots taken at each hour were analyzed by ion chromatography to measure magnesium concentration. The highest magnesium removal was observed for temperature 230 °C. X-ray diffraction (XRD) and scanning electron microscopy (EDS-SEM) analysis proved that the product formed was magnesium sulphate monohydrate crystals. Thermogravimetric analysis coupled with a mass spectrometer was used for the evaluation of the thermal stability of magnesium sulphate monohydrate. It was found that MgO and SO2 were formed by the decomposition of the salt at 1100 °C.