Giardia Die Off in Anaerobically Digested Wastewater Sludge During Composting

In the Perth metropolitan area, sludge from primary and secondary treatment is anaerobically digested in a two phase, mesophilic process, before being dewatered by belt press or centrifugation. Currently, all of the sludge produced is either stored on site, or composted by contractors and sold as a soil amendment. The composting processes and the quality of the marketed product are currently not subject to regulation. However, sludge use guidelines are expected to be released, which will specify a range of requirements for sludge based products intended for land application.