This second part in our debate about some claims of the benefits of Ductile Iron over PVC, we look at total lifecycle and sustainability of the product.
CLAIM - Ductile iron is a recycled and recyclable product that requires less pumping energy than alternatives (generating fewer greenhouse gases)...
The truth About PVC
PVC is one of the most well researched and tested materials in terms of environmental credentials. At least 60 reputable life cycle assessments have been carried out on PVC since 1985. The weight of evidence from these studies and the recent changes to the PVC Credit in Green Star confirms that PVC’s environmental credentials are sound when compared to alternative materials including Ductile Iron. Some facts
PVC pipe is the material with the least energy consumption, and least CO2 emissions while the recycled Ductile Iron pope shows the poorest results from the perspective of energy consumption and CO2 emissions.
If recycled material is used in manufacture of the Ductile Iron pipe, the energy consumption is still 26% higher than for the PVC pipe
The most unfavourable case corresponds to ductile iron pipes without recycled material, in which the energy consumption, in the region of 56% higher than PVC (1).
Research conducted by CSIRO found PVC pressure pipe to have significantly lower embodied energy than ductile iron (2).
1.Recio, J., M., B.; Guerrero, P., J.; Ageitos, M., G.; Narvaez, R., P.; 2005. Estimate of energy consumption and CO2 emissions associated with the production, use and final disposal of PVC, HDPE, PP ductile iron and concrete pipes. Barcelona
2.Ambrose, M.D., Salomonsson, G.D., Burn, S.; Piping Systems Embodied Energy Analysis. CSIRO 2002