Physicochemical Problems of Mineral Processing COMPARISON OF CHEMICAL AND BIOLOGICAL LEACHING OF SULFIDE TAILINGS

Abstract: Sulphidic tailings from Finnish Hitura nickel mine and Pyhäsalmi multi-metal mine were leached using sulphuric acid and bioleached. The aim was to recover minor amounts of valuable Cu, Ni, Zn and Mn. Both tailings consisted mainly of iron and magnesium-containing minerals and acid neutralizing minerals. The solution after chemical leaching tests contained mostly iron and magnesium, in Hitura up to 11 g/dm 3 Fe and 38 g/dm 3 Mg while in Pyhäsalmi 8-9 g/dm 3 Fe and 4 g/dm 3 Mg. Amount of these metals was 20-100-fold larger than amount of valuable metals, which were typically 100-300 mg/dm 3 . Problems in chemical leaching were high consumption of acid and poor selectivity. Bioleaching using iron and sulphur oxidizing bacteria was more selective towards the valuable metals. Both in leaching and bioleaching the high concentration of iron and magnesium in solution will make metals recovery challenging

Plastic value chains: Case: WEEE (Waste Electrical and Electronic Equipment) : Part 2 Report

This project identifies improvements in plastics recycling from Nordic electronic waste. Limited improvement is possible through modest changes in the existing value chain, such as ensuring that wastes are directed as intended. But for the most part, enhanced plastics recycling implies higher costs. The necessary changes could be driven in part through revised policy and regulatory instruments. These changes might, in turn, encourage more positive engagement from electronics producers. The report is part of the Nordic Prime Ministers' overall green growth initiative: “The Nordic Region – leading in green growth”. Read more in the web magazine “Green Growth the Nordic Way” at www.nordicway.org or at www.norden.org/greengrowt

WEEE Plastics Recycling : A guide to enhancing the recovery of plasticsfrom waste electrical and electronic equipment

The purpose of this guide is to inform and assist different stakeholders in the Nordic region to enhance the recycling of plastic materials from WEEE – Waste Electrical and Electronic Waste. It presents recommendations to various parties: consumers, authorities and policy-makers, recyclers and waste operators, as well as electronics producers.The guide was compiled as part of the Nordic Prime Ministers’ initiative, The Nordic Region – leading in green growth. Read more at www.norden.org/greengrowth or in the web magazine Green Growth the Nordic Way at www.nordicway.or

Plastic value chains : Case: WEEE (Waste Electric and electronic equipment) in the Nordic region

This project identifies thousands of tonnes per annum of potential enhanced plastics recycling from Nordic electronic waste. Plastics recycling does not always feature prominently in waste treatment. Recycling is technologically viable although the market and economic landscape is challenging. Easy export markets for waste plastic are largely closed and near-source treatment is increasingly needed. Concerns include issues of quality and worries about hazardous materials. Positively engaging electronics producers - beyond the bare punitive requirements within extended responsibility schemes – is a crucial driver for further developments. The report is part of the Nordic Prime Ministers’ overall green growth initiative: “The Nordic Region – leading in green growth”. Read more in the web magazine “Green Growth the Nordic Way” at www.nordicway.org or at www.norden.org/greengrowth The report for Part 2 will be published in December 2014

Investigating Europe's secondary raw materials markets

Secondary raw material (SRM) markets are key to delivering a circular economy in the EU. These markets can ensure the timely circulation of good-quality recycled materials in the European economy, which minimises the need to extract natural resources as a result. This report develops a new framework for assessing SRM market functionality. Of the eight SRM markets assessed under this framework, only three are well-functioning (aluminium, paper and glass). These markets were established a long time ago, are international and open, and occupy a significant market share of their respective material supply. Five assessed SRM markets (wood, plastics, biowaste, aggregates from construction and demolition waste, and textiles) are not well-functioning. The main reasons are their small size, weak demand (even with increasing supply) and inadequate technical specifications. Despite the strong policy push to increase recycling and the steady supply of recyclates that has resulted from this, the supply side of SRM markets is challenged. The main problems are insufficient specifications such as the end-of-waste criteria, and the presence of hazardous substances in recycled materials. The demand side, on the other hand, is characterised by a lack of trust in SRMs. There is hesitance to invest in technologies that would integrate SRMs into raw material supply operations. A cross-cutting issue impacting market functionality is the lack of adequate information for interested stakeholders, and the absence of a monitoring mechanism to observe the market and propose improvements. There are a few pathways to help SRM markets function more smoothly. These include expanding or modifying existing policy tools at the EU level; for example, by including fee eco-modulation in extended producer responsibility schemes. Otherwise, pathways include extending the use of green public procurement; making recycling targets more effective or expanding them to more waste materials; further developing end-of waste criteria; and widening the scope of recycled content requirements. Entirely new policy measures also help. For instance, further developing harmonised, EU-wide technical standards for SRMs could be beneficial. It would also be helpful to create a level playing field for primary and secondary raw materials by considering environmental externalities through taxing primary raw materials or reducing the VAT on SRMs