A life cycle assessment of the cradle-to-gate phases of clay brick production in South Africa

摘要

Quantified environmental impacts associated with clay brick production are not very well researched for the South African context. This paper, based on a study undertaken for the Clay Brick Association of South Africa, where clay bricks are still the predominant wall construction material, identifies processes within the various clay brick firing techniques, where environmental impacts are the most severe, with the intention to make producers aware of where they may improve production processes and reduce adverse environmental impacts. The paper will focus on the research results of the cradle-to-gate phase of the life cycle of clay bricks. The data collected from the full population survey were used to identify and model the environmental impacts using SimaPro software and the Ecolnvent database. The results for the full industry (averaged across firing technologies) per kg of fired clay brick for the impact categories assessed are: carcinogens 0.007315 kg C_2H_3Cl eq, non-carcinogens 0.031052 kg C_2H_3Cl eq, respiratory inorganics 0.000426 kg PM2.5 eq, ionizing radiation 1.070064 Bq C-14 eq, ozone layer depletion ＜0.0000 kg CFC-11 eq, respiratory organics 0.000076 kg C_2H_4 eq, aquatic ecotoxicity 77.239 kg TEG water, terrestrial ecotoxicity 21.27 kg TEG soil, terrestrial acidificationitrification 0.0088 kg SO_2 eq, land occupation 0.001759 m~2org.arable, aquatic acidification 0.004045 kg SO_2 eq, aquatic eutrophication 0.000150 kg PO_4 P-lim, global warming 0.853033kg CO_2 eq, non-renewable energy 8.99914 MJ primary and mineral extraction 0.000558 MJ surplus. Overall, the findings suggest that there is great potential to improve the clay brick manufacturing industry in terms of its environmental impacts.