5,538 research outputs found
Plastics recycling and sampling
No full textThis is the author accepted manuscript. The final version is available from AusIMM via the link in this record.This contribution examines the effect of feedstock sampling before the sorting stage of PET bottle recycling. Batches of waste PET bottles may contain non-PET bottles which need to be removed by sorting. Any residual presence of PVC is detrimental for the quality of products manufactured from recycled PET. The maximum tolerated concentration of PVC in
cleaned PET is extremely low, which places high demands on the recovery of PVC achieved by sorting. To be confident of attaining the desired PET quality after sorting, acceptance sampling of truckloads of PET bottles may take place prior to sorting. It is shown that accounting for sampling uncertainty requires that the sorting process achieves a consistently
high recovery of PVC bottles
Geometallurgy: driving innovation in the mining value chain
No full textThis is the author accepted manuscript. The final version is available from AusIMM via the linkGeometallurgy is a discipline which seeks to improve the sustainability of the extraction of
metals and minerals by promoting the smarter use of non-renewable resources, better
energy efficiency and greater use of renewable energy. To achieve these goals,
development of innovative technologies and approaches are being developed along the
entire commodity value chain, starting with exploration and extraction and extending to reuse
and recycling. This paper discusses the geometallurgy of industrial minerals with special
emphasis on kaolin, a versatile industrial mineral applied in ceramics, paper, paint, plastics,
rubber, pharmaceuticals, cosmetics, ink, sealants, adhesives, sanitaryware, glass fibre,
toothpaste, animal feed, etc.. Aspects of kaolin extraction in southwest UK are analysed
from a geometallurgical perspective. While geometallurgy already features in kaolin
extraction, its role can be significantly expanded by combining advanced in-pit
characterisation and orebody modelling with integrated planning and control of the refining
and calcination process. This paper highlights the importance of innovation in realising the
full potential of geometallurgy.The author would like to thank Daniel Goodman (Jacobs UK Ltd), Aurela Shtiza (IMA Europe), and Imerys Minerals Ltd for supporting this study. The author acknowledges funding as part of the Sustainable Technologies for Calcined Industrial Minerals (STOICISM, www.stoicism.eu) project funded by the European Union’s 7th Framework Programme (FP7/2007-2013) under grant agreement number 310645
SC author and illustrator Kate Salley Palmer signing book
No full textPhotograph of SC author and illustrator Kate Salley Palmer signing boo
Optimising multivariate variographic analysis with information from multivariate process data modelling (partial least squares)
No full textThis is the author accepted manuscriptWhereas a classical tool from the Theory of Sampling (TOS), variographic analysis, can address practical
situations with multiple variables, its application has very often been limited to one variable at a time. Recent
developments have shown the benefits of using multivariate approaches for variographic characterisation of
a set of variables instead of considering individual variables sequentially. Among these approaches, the
multivariogram has been revealed itself to be a powerful tool when the overall time-variability of a process
must be summarized in terms of a large set of properties (variables) to assess its true global variability.
However, even when choosing carefully the properties of interest for the process tested to avoid
unnecessary variance increase, the resulting global variance with this approach is very high. In particular,
some variables which contribute to a major proportion of the global (multivariate) variability could be less
important for the process performance than others having a lower variability. To address this issue, a new
approach is proposed, combining the multivariogram with process modelling and multivariate data analysis
methods such as Partial Least Squares (PLS) regression from chemometrics. An example from the mineral
processing industry is presented, for which the process performance could be linked to key process
variables (sensor data) using the PLS regression. Once introduced in the multivariogram equation, PLS
model parameters (loading-weights or regression coefficients) can be used to weigh the variables according
to their relevance for the process. In addition, this also permits characterisation of process performance
variability with time using only the process input variables and a weighted metric according to the PLS
regression model. Ultimately, this method helps to find an optimized sampling procedure in terms of
frequency, sampling mode and number of increments according to the actual overall process performance.
This approach has potentially many applications in the mining, feed and food, pharmaceutical or any other
industry for which it can be used to reduce risks and ensure a better use and management of resources.This work has been supported by the European FP7 project “Sustainable Technologies for Calcined
Industrial Minerals in Europe” (STOICISM), grant NMP2-LA-2012-310645
Book signing by SC author and illustrator Kate Salley Palmer
No full textPhotograph of Book signing by SC author and illustrator Kate Salley Palme
High-resolution clean-sc
No full textIn this paper a high-resolution extension of CLEAN-SC is proposed: HR-CLEAN-SC. Where CLEAN-SC uses peak sources in “dirty maps” to define so-called source components, HR-CLEAN-SC takes advantage of the fact that source components can likewise be derived from points at some distance from the peak, as long as these “source markers” are on the main lobe of the Point Spread Function (PSF). This is very useful when sources are closely spaced together, such that their PSFs interfere. Then, alternative markers can be sought in which the relative influence by PSFs of other source positions is minimised. For those markers the source components better agree with the actual sources, which allows for better estimation of their locations and strengths. This paper outlines the theory needed to understand this approach and discusses applications to 2D and 3D microphone array simulations with closely spaced sources
SC author and illustrator Kate Salley Palmer talking to event attendees
No full textPhotograph of SC author and illustrator Kate Salley Palmer talking to Rita Lewi
Ca-modified Al–Mg–Sc alloy with high strength at elevated temperatures due to a hierarchical microstructure
No full textAl-Mg alloys are normally prone to lose part of their yield and tensile strength at high temperatures due to insufficient thermal stability of the microstructure. Here, we present a Ca-modified Al–Mg–Sc alloy demonstrating high strength at elevated temperatures. The microstructure contains Al4Ca phases distributed as a network along the grain boundary and Al3(Sc,Zr) nano-particles dispersed within the grains. The microstructure evolution and age-hardening analysis indicate that the combination of an Al4Ca network and Sc-rich nano-particles leads to excellent thermal stability even upon aging at 300 °C. The tensile strength of the alloy for temperatures up to 250 °C is significantly improved by an aging treatment and is comparable with the commercial heat-resistant aluminum alloys, i.e., A356 and A319. At a high temperature of 300 °C, the tensile strength is superior to the above-mentioned commercial alloys, even more so when expressed as the specific strength due to the low density of Ca-modified Al–Mg–Sc alloy. The excellent high-temperature strength results from a synergistic effect of solid solution strengthening, grain boundary strengthening and nanoparticle order strengthening.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Novel Aerospace Material
SC-Square: Overview to 2021.
No full textThis extended abstract was written to accompany an invited talk at the 2021 SC-Square Workshop, where the author was asked to give an overview of SC-Square progress to date. The author first reminds the reader of the definition of SC-Square, then briefly outlines some of the history, before picking out some (personal) scientific highlights
SC-Square: Overview to 2021.
No full textThis extended abstract was written to accompany an invited talk at the 2021 SC-Square Workshop, where the author was asked to give an overview of SC-Square progress to date. The author first reminds the reader of the definition of SC-Square, then briefly outlines some of the history, before picking out some (personal) scientific highlights
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