Platinum group elements (PGEs) are increasingly being used in a variety of environmentally-related technologies such as catalysts and catalytic converters which have strong expected growth to meet environmental and technological challenges this century. The platinum industry is actively seeking to progress its commitment to sustainability principles by reducing the negative impacts of their mining and mineral processing operations. Technical innovation to improve future plant designs, as well as the development of management policies, guidelines and protocols for efficient operation of process plants has therefore become a strategic priority for the South African platinum industry. The industry has also made an effort to understand the environmental impacts of its products from mine to metal, using life cycle methods. However, very limited research has been done to investigate what environmental value could be created if strategic and design decisions in minerals processing were life cycle based, particularly in the context of PGMs. Seminal work by Stewart (1999) investigating the environmental life cycle consideration for design-related decision making in the minerals industry has not led to significant adoption. Forbes et al. (2000) analysed metal processing using LCA and were able to identify opportunities for improved environmental performance. They however did not explore how it would be incorporated into the decision making cycle. Therefore, the main objective of this research is to determine whether life cycle assessment could help inform design decision making in the minerals industry. In the years 2002-2008 several PGM-producing companies commissioned new S02 scrubbing technologies to meet the regulations that had been set to prevent the release of excessive amounts of sulphur dioxide from smelters in the Rustenburg area, a mining town located in the North West Province of South Africa. Using these cleanup process retrofits as case studies, this dissertation aims to determine whether the introduction of LCA as an environmental analysis tool would have provided additional value to the decision makers. The case study approach that was chosen compared and assessed the performance of S02 abatement technologies and the effect of efficiencies chosen on environmental performance by using life cycle assessment modelling. By doing the life cycle assessment on the different options that the companies had, it was possible to evaluate the indirect environmental impacts that could have been overlooked during the design decision making process. In addition , experts who were involved in the design processes of the S02 abatement retrofits were interviewed to establish: i) how the design decisions were made and ii) whether the life cycle based insights into technology performance would have been of use in the design work. The goal of the life cycle assessment was to identify whether there were design decisions that induced environmental burden shifting when platinum smelters in the Rustenburg area added S02 abatement technologies to their processes, which could have been avoided had the LCA perspective been taken into account. The assessments considered two key variables, namely extent of recovery and technology choice. The study shows that the energy requirements increase exponentially with increasing recovery for both technology options. This is a result of the increased pumping energy requirements which are directly related to the increasing quantities of solvent that have to be pumped. The environmental impacts that were analysed during the Life Cycle Impact Assessment (LCIA) phase were: abiotic resource depletion, fossil fuel depletion, acidification, global warming , human toxicity and water depletion. The background processes for soda ash and lime production dominated abiotic resource depletion, fossil fuel depletion , global warming potential and human toxicity impacts that were associated with the concentrated dual alkali process. The foreground system had significant effects on the acidification potential, water depletion as well as global warming potential. For the scrubber with acid plant, the transportation of the acid that was produced and the sulphuric acid production used in the system expansion were observed to have a major impact on most of the impact categories, with the exception being the acidification potential and water depletion in which the foreground system was the principal contributor to the impact categories. The magnitude of impacts increased with increasing recovery in the concentrated dual alkali case with the only exception being the acidification potential. For the scrubber with acid plant option, the magnitude of impacts decreased with increasing recovery with the exception being the amount of water used and the global warming potential. Overall, the LCA revealed that the scrubber with acid plant choice mostly has significantly lower environmental impacts. The results of the LCA were then presented to design experts as way of gaining insights as to whether or not carrying out a life cycle assessment during the design phase would be capable of informing and influencing design decision making in mining companies. The interviews were also used as a platform to gain a better understanding of how design decision making works in the mining sector. The expert interviews revealed that the decision making process is not an individual job but rather requires input from different project teams. Before a decision is made they would all need to agree unanimously on a specific technology option which they would all deem beneficial after carrying out a cost benefit analysis. With regards to decisions on retrofitting , the major drivers were identified to be the case in which design specifications were not being met, surfacing of new regulations or availability of improved technology. With regards to choosing between technologies that satisfied the same purposes the interviewees felt that the main determinant would be the quality of gas to be treated. Once this had been established, the company would then decide on whether or not they wanted to opt for a high OPEX or high CAPEX process depending on their financial stability. Most of the interviewees felt that companies did not do much to incorporate environmental concerns into their design apart from doing the prescribed Environmental Impact Assessment (EIA). Therefore once presented with the LCA results from the study they felt that such an assessment would be really useful especially if it were to be incorporated during the early stages of the design. By so doing the environmental aspects would gain more weighting in the decision making matrix that is used. The major concern that was brought up was that in as much as the LCA quantified the impacts associated with the different options, and a comparison was made between the different key variables, it would be difficult to make decisions without also including a rational and consistent normalisation process. This would help decision makers see the relevance of the impacts presented to them, by relating them to some form of reference system. It is concluded that in the case analysed, LCA would have generated useful further insights to the design team on the technology and design variable choices. Additionally, there would be some interest from design decision-makers to include such insights into design projects if this could be done without introducing significant extra work or delays.

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