Rotorua Now – Wastewater research for more sustainable results

Researchers at the University of Canterbury are developing a new decision-making tool to help identify how wastewater treatment can be made more sustainable.

The research of Te Whare Wānanga o Waitaha | PhD student Madeline Furness and Associate Professor Ricardo Bello-Mendoza from the University of Canterbury, working with Professor Rolando Chamy from Pontificia Universidad Católica de Valparaíso, Chile, examined two wastewater treatment plants in Santiago, Chile, using the data to create a ​Develop a modeling tool to improve benefits and minimize impact on wastewater treatment.

Associate Professor Ricardo Bello-Mendoza says the two ‘biofactories’ in Chile are a good example of how wastewater treatment can be made more sustainable.

“Our research looks at wastewater sustainability from three pillars – environmental, economic and social – and the tools used to assess each of these pillars, such as Life Cycle Costing and Social Life Cycle Assessments,” says Ricardo.

“It then combines the tools to develop a model that we can use to identify and run different combinations of processes to find out which ones deliver the best results in terms of reducing environmental impact, reducing costs, improving benefits and looking at social processes. implications.

“This is a sector that does not adapt quickly because it is expensive to invest in new technology. By using our modeling tool, we can improve the environmental performance and sustainability of wastewater treatment plants without necessarily making large investments.”

For example, he says it can help make decisions about chemical inputs or process conditions that improve wastewater quality while minimizing negative impacts, such as higher greenhouse gas emissions or toxicity.

The research also introduces the concept of a wastewater circular economy approach – WW-CE, where wastewater is viewed as a potential source of resources.

“Traditional wastewater treatment takes a linear approach, treating wastewater to produce a wastewater that can be safely discharged into the environment and the ocean,” says Ricardo.

“In a circular economy, we don’t see wastewater as a problem, but more as a resource recovery park through the recovery of treated water, biosolids, nutrients, bioenergy and biomaterials. For example, nitrogen and phosphorus found in water can be recovered and used in agriculture, and in some places the treated water can be used for irrigation.

“When transitioning to WW-CEs, one of the bioplants we studied improved overall sustainability by 30 percent, and the second plant improved by 48 percent. This approach has the potential to revolutionize global sanitation.”

Associate Professor Bello-Mendoza says the next phase of this research is to adapt the tool to a New Zealand context and discuss the practical applications of this research with local councils.

“The factory farms are good examples of processes that we are not yet using here in New Zealand. Although there are some examples of resource recovery efforts – for example in Christchurch the biological sludge produced during wastewater treatment is converted into methane and used as fuel to produce electricity for the power station, and in Auckland they use recovered struvite as fertilizer – there is significant potential for improvement.”

This research was funded by the University of Canterbury, the Pontifical Catholic University of Valparaiso, Chile, and the Chilean National Agency for Research and Development. The fieldwork was carried out with the support of Aguas Andinas, Chile.

Read more about Associate Professor Ricardo Bello-Mendoza’s research here