Calculating the Carbon Footprint of Biological Nutrient Removal (BNR) Plants

This paper compares the relative carbon footprints and costs for the several example waste water treatment BNR facilities, from construction through to demolition over 40 years. The processes investigated were Johannesburg, Modified Ludzack-Ettinger (MLE), Step BNR, Simple Step Feed and Multi Sludge. To enable a critical assessment and comparison of the carbon footprint of the various treatment techniques, an attempt to determine as accurately as possible the carbon emissions for materials used in the construction and running of these wastewater treatment facilities has been made via purpose-constructed models.