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Funding Information: Funding: This research was funded by the Kaute Foundation and grant number was 20210327 Optimization and dynamic modelling of slag-matte interactions in an industrial scale continuous flash smelting settler. The APC was funded by the Aalto University. Funding Information: Acknowledgments: Financial support from the Kaute Foundation is deeply appreciated, and the Aalto School of Chemical and Metallurgical Engineering is also gratefully acknowledged for providing the proper research environment and research facilities. The computational resources for this project were provided by CSC Finland. Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. A mathematical modeling approach was used to test different design modifications in a flash smelting settler to reduce the copper losses in slag, which is economically disadvantageous for copper processing using the pyrometallurgical route. The main purpose of this study was to find ways to reduce copper losses in slag by improving the settling and coalescence of copper matte droplets, in particular, the smallest droplet sizes of ≤100 µm. These improvements inside the flash smelting (FS) settler were targeted through different settler design modifications. Three different design schemes were tested using the commercial computational fluid dynamics (CFD) software, Ansys Fluent. These settler design modification schemes included the impact of various baffle types, positioning, the height inside the settler, and settler bottom inclinations. Simulations were carried out with and without coalescence and the results were compared with normal settler design. The results revealed that the settling phenomenon and coalescence efficiency were improved significantly with these design modifications. It was concluded that a single baffle design was optimal for reducing copper losses and increasing coalescence efficiency instead of using multiple baffle arrangements. The top-mounted baffle outperformed the bottom-mounted baffle and inclined settler design.

Computational methods have become reliable tools in many disciplines for research and industrial design. There are, however, an ever-increasing number of details waiting to be included in the models and software, including, e.g., chemical reactions and many physical phenomena, such as particle and droplet behavior and their interactions. The dominant method for copper production, flash smelting, has been extensively investigated, but the settler part of the furnace containing molten high temperature melts termed slag and matte, still lacks a computational modeling tool. In this paper, two commercial modeling software programs have been used for simulating slag&ndash, matte interactions in the settler, the target being first to develop a robust computational fluid dynamics (CFD) model and, second, to apply a new approach for molten droplet behavior in a continuum. The latter is based on CFD coupled with the discrete element method (DEM), which was originally developed for modeling solid particle&ndash, particle interactions and movement, and is applied here for individual droplets for the first time. The results suggest distinct settling flow phenomena and the significance of droplet coalescence for settling velocity and efficiency. The computing capacity requirement for both approaches is the main limiting factor preventing full-scale geometry modeling with detailed droplet interactions.

Helminth Parasites of Little Cormorant, Phalacrocorax niger from central District Sanghar of Sindh Pakistan were investigated during December 2014-2015. Little Cormorant,P. niger is fish eating, migratory cum resident bird, harbour diverse parasites and commonly found in water bodies of the study area. Eleven hosts (P. niger) were examined in Parasitological Laboratory of Zoology department, Sindh University Jamshoro. Only one host was harbouring two specimens of acanthocephalan. These were collected from intestine and have proboscis with four circles of spines, eleven circle of collar spine with 14 spines in each circle, sacculate proboscis receptacle, tubular lemenisci, cylindrical testes and long cement glands. These features correspond to generic features of genus PallisentisVan Cleave, 1928. However, genus Pallisentis usually collected from freshwater fishes and has not been reported from birds. Therefore, present infection in Little Cormorant might be result of its piscivorous feeding habit. Present paper deals first record of genusPallisentisVan Cleave, 1928 in Little Cormorant, P. niger from Pakistan. Keywords: Acanthocephalan; Little Cormorant; Phalacrocorax niger; Pallisentis; Intestine http://dx.doi.org/10.19045/bspab.2016.50163

We report the observation of room-temperature optical gain at 1.3 mu m in electrically driven dilute nitride vertical cavity semiconductor optical amplifiers. The gain is calculated with respect to injected power for samples with and without a confinement aperture. At lower injected powers, a gain of almost 10 dB is observed in both samples. At injection powers over 5 nW, the gain is observed to decrease. For nearly all investigated power levels, the sample with confinement aperture gives slightly higher gain.