Chemical Technology May 2015

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REGULAR FEATURES 3 Comment by Carl Schonborn, PrEng, consulting editor, ‘Chemical Technology’

RENEWABLES 20 The profitable business of climate change adaptation “In marketing terms the end of the world will be very big,” says Ben Elton in his novel,‘This Other Eden’.“Anyone trying to save it should remember that.” And – meeting all our end-of-world fantasies – is climate change. by Gavin Chait MINERALS PROCESSING AND METALLURGY 24 Evolution of Acid Mine Drainage formation in sulphidic mine tailings Sulphidic mine tailings are among the largest mining wastes on Earth and are prone to produce acid mine drainage (AMD). The formation of AMD is a sequence of complex biogeochemical and mineral dissolution processes which can be classified in three steps from the operational phase of a tailings impoundment until the final appearance of AMD after operations ceased. This review summarises the work of 20 years of research on AMD’s evolution and the controlling parameters of AMD formation in this type of mine waste. by Bernhard Dold, SUMIRCO (Sustainable Mining Research & Consult EIRL), San Pedro de la Paz, Chile

23 SAIChE IChemE news/ Welcoming our consultant 36 Et cetera/ Sudoku 105/Solution to Sudoku 104 COVER STORY 4 Is (over) regulation stifling innovation?

Over the past two decades, the South African government has, in the author's opinion, moved from the permissive regulatory environment of the past which fostered and nurtured innovation, to the restrictive regulatory environment such as that in Europe. by Janusz Luterek, PrEng, Hahn & Hahn WATER TREATMENT 6 Removal of copper from wastewater by cementation from simulated leach liquors This article is concerned with the study of copper cementation in batch reactors containing rotating iron cylinders. Copper has been selected for two reasons: removal of toxic metals whose effects on the environment have been clearly proven and the fact that copper is a valuable saleable product. Iron has been chosen as a sacrificial metal because of its availability and its low cost . by Ehssan Nassef, Department of Petrochemical Engineering, Faculty of Engineering, Pharos University, Alexandria, Egypt and Yehia A El-Taweel, Department of Chemical Engineering, Faculty of Engineering, Alexandria University, Alexandria, Egypt 12 New solutions needed to recycle fracking water Rice University scientists have performed a detailed analysis of water produced by hydraulic fracturing (aka fracking) of three gas reservoirs and suggested environmentally friendly remedies are needed to treat and reuse it. by MikeWilliams and David Ruth, Rice University, Houston,Texas, USA

Transparency You Can See Average circulation (July – September 2014) Paid: 17

Free: 3 687 Total: 3 704

Chemical Technology is endorsed by The South African Institution of Chemical Engineers

34 Focus on minerals processing and metallurgy

and the Southern African Association of Energy Efficiency

DISCLAIMER The views expressed in this journal are not neces- sarily those of the editor or the publisher. Generic images courtesy of www.shutterstock.com

15 Focus on water treatment

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