1,721,000 research outputs found
Photovoltaic panel recycling: from type-selective processes to flexible apparatus for simultaneous treatment of different types.
Full text linkPhotovoltaic (PV) technology for renewable energy utilization is constantly growing throughout the world. This widespread application is going to determine the disposal of large amounts of wastes (as end of life panels): only in Europe about 500,000 ton/year are expected in the next 20 years. European Union issued the Guideline 2012/19/EU in order to fix rules about end of life photovoltaic panel’s treatment establishing both collecting rates and minimum recovery targets. Currently the dominant PV technology uses crystalline silicon (monocrystalline and polycrystalline) as semiconductor, but the thin film photovoltaic modules using cadmium telluride (CdTe), amorphous silicon, Copper Indium Gallium Selenide (CIGS) and Copper Indium Selenide (CIS) are recently getting much more importance. Wastes of PV installations are secondary raw materials which could be treated in order to recover glass and Al, but also other metals such as Cu, Ti, Ag, Te, In, Se, Ga, along with plastic and metallic components of electronic equipment. Many recent efforts were devoted to the treatment of end of life panels, but only two full scale processes were developed for crystalline silicon modules (Deutsche Solar) and CdTe panels (First Solar). Furthermore, recent developments concerned with new technologies designed for treating together more kinds of photovoltaic panels by automated processes. In this work a picture of the PV world in terms of market, typology, waste dynamics and recoverable materials will be given. A description of full scale processes will be reported evidencing products and yields of recovery. A case study of process development for the simultaneous treatment of different kinds of PV panels will be presented. In particular experimental results in lab and pilot scale will be described regarding the development and optimization of a process including both physical pre-treatment and hydrometallurgical recovery of target metal concentrates. The process will be validated in pilot scale within the activities of the Photolife project (LIFE13 ENV/IT/001033) financed by European Community in the LIFE+ program
Recycling of photovoltaic panels by physical operations
No full textRecycling of polycrystalline silicon, amorphous silicon and CdTe photovoltaic panels was investigated by studying two alternative routes made up of physical operations: two blade rotors crushing followed by thermal treatment and two blade rotors crushing followed by hammer crushing. Size distribution, X-ray diffraction and X-ray fluorescence analysis of obtained products were carried out in order to evaluate their properties as valuable products. Results showed that for all kinds of investigated photovoltaic modules the two blade rotors crushing followed by hammer crushing and eventually by a thermal treatment of d > 1 mm fractions, was the best option aiming to a direct recovery of glass. (C) 2014 Elsevier B.V. All rights reserved
Non-electrostatic surface complexation models for protons and lead(II) sorption onto single minerals and their mixture
No full textPotentiometric titrations and lead sorption tests were conducted using muscovite, clinochlore, hematite, goethite, quartz, and a mixture of these same minerals. Mechanistic models were developed to represent and interpret these data. The aim was isolating the specific contribution of each mineral in proton and lead binding. Acid-base properties of each single mineral as well as their mixture were represented by discrete models, which consider the dissociation of n monoprotic sites (n-site/n-K-H models). A one-site/one-K-H model (logK(H1) = 10.69) was chosen for quartz (dissociation of SiOH edge hydroxyl groups). Goethite and hematite (FeOH groups) were represented by the same one-site/one-K-H model (logK(H1) = 10.35). Three-site/three-K-H models were used for muscovite (logK(H1) = 4.18; logK(H2) = 6.65; log K-H3 = 9.67) and clinochlore (log K-H1 = 3.84; log K-H2 = 6.57; log K-H3 = 9.71) assuming that SiOH and AlOH of the alummosilicate matrix dissociate in the acid-neutral pH range while SiOH groups of quartz inclusions dissociate in the basic range. Similarly, the mixture of these minerals was represented by a three-site/three-K-H model (log K-H1= 3.39; log K-H2 = 6.72; log K-H3 10.82). According to crossed comparisons with single minerals, the first two sites of the mixture were associated with the aluminosilicate matrix (SiOH and AlOH respectively) and the third site with iron oxides (FeOH) and quartz groups. Additivity of proton binding in the mixture was demonstrated by simulating the mixture's titration curve. A unified model for the entire set of titration curves (single minerals and mixture) was also developed introducing a three-peak distribution function for proton affinity constants. Experimental data for lead sorption onto the mixture and individual minerals in 3-5 pH range denoted the competition between protons and metallic ions. The entire set of lead isotherms (individual mineral and mixture data) was represented adequately by a unified model taking into account both monodentate and bidentate complexes with the three active sites (additivity of lead binding). Experimental data of metal distribution in solid and liquid phases were successfully simulated by implementing the protonation and the surface complexation constants into the database of a dedicated software for chemical equilibria. (c) 2005 Elsevier Ltd. All rights reserved
Development of a hydrometallurgical process for automobile shredded residue valorisation
No full text
Product recovery from Li-ion battery wastes coming from an industrial pre-treatment plant: Lab scale tests and process simulations
No full textIn this paper two hydrometallurgical processes were analyzed for recovery of lithium and cobalt from lithium ion batteries. The effect of adding a secondary purification step by solvent extraction was evaluated in terms of product purity and economical feasibility of the process. Process routes were made of the following steps: mechanical pretreatment, leaching, primary (and secondary) purification, product recovery. Electrodic material used in leaching experiments was produced in a large scale pre-treatment plant for waste recycling. Leaching tests were performed both using chloridric acid and sulphuric acid plus glucose. In optimized conditions quantitative extraction of Co and Li were obtained for both tested systems. Iron, aluminum and copper were removed by precipitation as hydroxides, while Ni can be separated only using solvent extraction. Process simulations showed that, for the same input flow rate of batteries, the addition of solvent extraction improves the economical feasibility of the process for lithium ion battery recovery. (C) 2012 Elsevier B.V. All rights reserved
Sequential extraction of heavy metals in river sediments of an abandoned pyrite mining area: Pollution detection and affinity series
No full textIn this paper heavy metal pollution at an abandoned Italian pyrite mine has been investigated by comparing total concentrations and speciation of heavy metals (Fe, Cu, Mn, Zn, Pb and As) in a red mud sample and a river sediment. Acid digestions show that all the investigated heavy metals present larger concentrations in the sediment than in the tailing. A modified Tessier's procedure has been used to discriminate heavy metal bound to organic fraction from those originally present in the mineral sulphide matrix and to detect a possible trend of metal mobilisation from red mud to river sediment. Sequential extractions on bulk and size fractionated samples denote that sediment samples present larger percent concentrations of the investigated heavy metals in the first extractive steps (I-IV) especially in lower dimension size fractionated samples suggesting that heavy metals in the sediment are significantly bound by superficial adsorption mechanisms. A modified Tessier's procedure, discriminating organic and sulphide bound metals, was used to detect pollutant mobilisation from red mud to river sediment in an abandoned pyrite mine. © 2004 Elsevier Ltd. All rights reserved
Photovoltaic panel recycling: from type selective processes to flexible apparatus for simultaneous treatment of different types
No full textPhotovoltaic (PV) technology for renewable energy utilisation is constantly growing throughout the world. Many recent efforts were devoted to the treatment of end-of-life panels, but only two full-scale processes were developed for crystalline silicon modules (Deutsche Solar) and CdTe panels (First Solar). Furthermore, recent developments concerned with new technologies designed for treating together more kinds of PV panels by automated processes. In this work, a picture of the PV world in terms of market, typology, waste dynamics and recoverable materials was given. A description of full-scale processes will be reported evidencing products and yields of recovery. A case study of process development for the simultaneous treatment of different kinds of PV panels was presented. In particular, experimental results in lab and pilot scale were described regarding the development and optimisation of a process including both physical pre-treatment and hydrometallurgical treatment for the recovery of target metal. © 2016 The Australasian Institute of Mining and Metallurgy
- …
