Does a catalytic converter cause more loss of lives than it saves? - A human health life cycle assessment study
Examensarbete för masterexamen
Industrial ecology (MPTSE), MSc
Islam, K M Nazmul
Purpose This study was conducted to investigate the production impacts and use phase benefits of a catalytic converter using the disability adjusted life year (DALY) indicator over its life cycle, starting from resource extraction to end of life management. The assessment was conducted for a generic three way ceramic honeycomb catalytic converter. The aims of the case study were to identify social hotspots of the catalytic converter’s life cycle and to evaluate whether the catalytic converter is saving more lives than are lost during production. Methods The case study was based on the human health focus approach and on the social life cycle assessment (SLCA) method described in the Guidelines for SLCA. All relevant stakeholders are included. Material and energy inputs, as well as outputs for unit processes of the catalytic converter production system, are determined from relevant patents and studies, and from the Ecoinvent V. 2.2 life cycle inventory database. To assess the human health benefits and production impacts, the ReCiPe impact assessment method was used. To assess the occupational health impacts, occupational DALY characterization factors (CFs) reported by Scanlon, et al., (2015) were used. Calculations were performed using the openLCA V. 1.4.1 software (GreenDelta, Berlin, Germany). Results and discussion In general, a catalytic converter causes more loss of lives (11 days) then it saves (4.5 days) under the egalitarian value perspectives for the baseline production scenario of 160,000 km functional life. Contrary to that, the catalytic converter saves lives (5.5 days and approx. 6 days for the hierarchist and individualist perspectives, respectively) than it causes loss (about 1 day and 0.6 days for the hierarchist and individualist perspectives, respectively)for the baseline production scenario for 160,000 km functional life under hierarchist and individualist perspectives. The geographical hotspot analysis reveals that, while the catalytic converter saves lives in Sweden where it is used, it causes more loss of lives elsewhere in the world, particularly in South Africa and Russia. In total, the loss of lives is around 11 days for the base line production system at low recycling rate and egalitarian perspective; at high recycling rate the loss of lives reduced to about 7 days. Overall, the DALY varies between 0.62 days and 11.3 days, mainly due to differences in value perspective. Conclusions The study showed that increased use of recycled platinum group metals, extended functional life of the catalytic converter, and value perspective can alter the health balance of the product system. This human health-focused SLCA case study identified methodological issues that need further attention, for example development of occupational DALY characterization factors (CFs) for the countries involved in the production of three way ceramic honeycomb catalytic converter, and emission DALY CFs for platinum group elements (PGEs)emitted during the use phase of catalytic converter.
Annan teknik , Other Engineering and Technologies