Evaluating the economics of and business models for metal recycling from waste printed circuit boards in a South African context

Manjengwa, Evelyn Ruvimbo (2019-04)

Thesis (MEng)--Stellenbosch University, 2019.


ENGLISH ABSTRACT: Electronic waste is the fastest growing component of solid municipal waste in South Africa however limited processing capacity exists in the country to economically recover metals from printed circuit board (PCB) waste. Presently the majority of recycled e-waste is exported instead of adding value to the processed material. A hydrometallurgical process entailing the selective leaching of gold and copper from waste printed circuit boards was developed by the research group (Rossouw, 2015; de Waal, 2018). This study sought to evaluate the economic and business viability of the proposed hydrometallurgical process within the South African context. A PESTEL approach was used to evaluate the South African recycling landscape. In this approach the status of the political, economic, environmental, legal, social and technological aspects characterising e-waste recycling and management was undertaken. Different business models were developed around the main activities of the associated operations of the proposed process. Screening and selection was done on two levels. An assessment of the collection and dismantling of e-waste was done and used as the first basis for screening the business models. It was established that the reverse logistics and associated manpower requirements and efficiencies associated with this operation were economically and operationally restrictive. Detailed costing and profitability studies were done on the last eight business models. The recovery of copper and gold in the metallic state was found to be associated with the highest capital and annual operating expenditures. Profitability studies were conducted on two levels. Performance analysis over the life of the project was done on the basis of discounted cash flows, time, cash and interest. The profitability ratios that included return on investment (ROI), capital ratio (CR), terminal capital rate of return ratio (CRRterm), present value ratio (PVR), net profit margin (NPM) and the (fixed asset turnover ratio) FATR were used to assess the annual performance of each business model. Both assessments revealed that all the business models under the specified process conditions, were unviable and incapable of both capital and interest repayment. Detailed sensitivity studies of the group 4 business was done. The risk of failure within five years was certain as evidenced by the perpetually decaying plots of the recapitalization risk curves. Four additional significant areas of risk were identified and evaluated that had an impact on the performance of the business models. These included supply and demand constraints, key raw material, technological and market related risks. A consideration of alternative revenue streams from palladium, silver and tin recovery, did not improve the performance of the business models. Decreasing both the capital costs and operating costs by margins ranging between 48% and 65% shifted the performance of the business models. The success of this project was driven strongly by the gold business, evidenced by improved performance at elevated minimum gold concentrations ranging between 563ppm and 925ppm. These concentrations implied that a consistent supply of high grade WPCBs would have to be furnished to ensure project viability. It is necessary to consider alternative processing routes when using medium grade WPCBs.

AFRIKAANSE OPSOMMING: Elektroniese afval is die vinnigste groeiende komponent van soliede munisipale afval in Suid-Afrika. Beperkte prosesseringskapasiteit bestaan egter in die land om metale uit gedrukte stroombaanpaneel (PCB) afval ekonomies te herwin. Tans word die meerderheid herwinde e-afval uitgevoer in plaas daarvan om waarde tot die geprosesseerde materiaal te voeg. ʼn Hidrometallurgiese proses wat die selektiewe loging van goud en koper uit afval PCB behels, is deur die navorsingsgroep ontwikkel (Rossouw, 2015; de Waal 2018). Hierdie studie het beoog om die ekonomiese en besigheidslewensvatbaarheid van die voorgestelde hidrometallurgiese proses binne die Suid-Afrikaanse konteks te evalueer. Gedetailleerde kosteberekeninge en winsgewendheidstudies is gedoen op die laaste agt besigheidsmodelle. Dis gevind dat die herwinning van goud en koper in die metaal toestand geassosieer word met die hoogste kapitaal en jaarlikse bedryfsuitgawes. Winsgewendheidstudies is uitgevoer op twee vlakke. Werkverrigting analise oor die lewensduur van die projek is gedoen op die basis van gediskonteerde kontantvloei, tyd, kontant en rente. Die winsgewendheid verhoudings wat opbrengs op belegging (ROI), kapitaal verhouding (CR), terminale kapitaal opbrengskoers verhouding (CRRterm), toonwaarde verhouding (PVR), netto winsgrens (NPM) en die FATR (vaste bate omset verhouding) is gebruik om die jaarlikse doeltreffendheid van elke besigheidsmodel te assesseer. Beide assesserings het aangedui dat al die besigheidsmodelle binne die gespesifiseerde proses kondisies nie lewensvatbaar was nie en onbevoeg is om beide kapitaal en rente terugbetalings te doen. Gedetailleerde sensitiwiteitstudies van die groep vier besigheid is gedoen. Die risiko van mislukking binne vyf jaar was seker soos bewys deur die onophoudelike afbreking stippe op die herkapitalisering risiko kurwes. Vier addisionele beduidende areas van risiko is geïdentifiseer en -evalueer wat ʼn impak op die prestasie van die besigheidsmodelle gehad het.

Please refer to this item in SUNScholar by using the following persistent URL: http://hdl.handle.net/10019.1/106085
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