The UNSW Odour Group through the CRC for Low Carbon Living is carrying out research to support the beneficial re-use of biosolids by Sydney Water

Cronulla OutlookUNSW is investigating key aspects relating to the Beneficial Reuse of Biosolids project. Aspects relevant to Sydney Water include:

  • Odour management
  • Optimisation of solids processing
  • Community Engagement

The inclusion of these aspects will increase options for the beneficial re-use of biosolids by understanding the odour potential of the biosolids, decreasing biosolids volume, increasing biogas production and decreasing community impact through appropriate community engagement.

Involved in the collaboration are Sydney Water, Suez Environnement, Prospect Water (BOO), Hunter Water and UNSW. This work will continue from ‘Biosolids Indicator’ project undertaken by Suez Environnement, Sydney Water and UNSW. 

Basis for Odour Management

Key odorants throughout the solids processing at different wastewater treatment sites were identified, and temporal and spatial variations in the emissions were noted.  The main variations between the sites thought to affect odour were identified as the sewer catchment, digestion and dewatering. 

UNSW collected the available operational data from a variety of sources (SCADA, EKAMS, production and operator logs) corresponding to the sampling times for the various sites.  No correlations between process operations and odour emissions were evident suggesting the need for more in depth monitoring of the solids treatment stream to understand the temporal variations in odour emissions observed. 

Basis for Community Engagement

Environmental complaints regarding industry-produced odour have been increasing numerically as well as severity in Australia. This has led to dire consequences for some industrial processes. Wastewater treatment and biosolids application are sectors that are potential sources of complaints. Despite this, there have been very few comprehensive community analyses with regards to odour complaints.

Using a combination of surveys, both for community and members of the industry, as well as odour tests and Gas Chromatography-Mass Spectrometry/Olfactometry analysis, we endeavoured to produce a set of tools that will help in predicting and ameliorating community dissatisfaction.

Next step: Cronulla WWTP Case-study

UNSW through the CRC for Low Carbon Living (LCL) is continuing the study with an in-depth study at Cronulla WWTP. The outcome for this research concerning odour is to benchmark odour emissions from the Cronulla site. The project also includes the optimisation of dewatering to reduce biosolids volume, and increasing biogas production in the digesters.  Suez Environnement is providing a peer review for the research, as well as advising on the purchase, installation and use of online sensors to be installed for the project.  The outcome of this research will be reviewed on what could be translated across other plants and where process improvements can be targeted.

Want to know more?

Ruth Fisher
Research Associate
Ruth.fisher@unsw.edu.au

Dr. Juan Pablo (J.P.) Alvarez Gaitan
Research Associate
j.alvarezgaitan@unsw.edu.au

James Hayes
Research Associate
j.e.hayes@.unsw.edu.au