Innovation to Use Biosolids as a Resource

Increasing reliance on biological nutrient-removal processes has improved effluent quality for wastewater treatment plants but can also produce larger volumes of wetter, more odorous and difficult-to-dewater biosolids, making transport to land-application markets a major cost.

 

The paper explores how Cambi’s thermal hydrolysis technology, particularly the post-digestion SolidStream configuration, can increase volatile-solids destruction, improve dewaterability and biogas production, and produce a lower-odour, pathogen-free Class A product. Results from a full-scale installation in Germany demonstrate the technology’s potential relevance to Australian utilities, including approximately 25% more biogas, cake solids of around 40–43%, and a 60% reduction in wet tonnes requiring transport or disposal.

 

The authors also assess a distinctly Australian opportunity: using land-applied biosolids to improve soil fertility, water retention and agricultural productivity while sequestering carbon and displacing emissions-intensive fertilisers. Against the backdrop of Australia’s Carbon Farming Initiative, soil-carbon methodologies and carbon-credit market, the paper calls for targeted research to quantify these benefits and establish biosolids application as an eligible emissions-reduction activity, creating potential long-term value for water utilities and rural landholders. 

 

Download the paper.