WU Published Study in the Chemical Engineering Journal

A new publication from our partners at Wageningen University sheds light on how human urine can be transformed into a valuable nutrient source for sustainable bioenergy production. The study, published in the Chemical Engineering Journal under the title Urine-derived solids as nutrient sources to enhance microbial wood degradation in a composting environment, explores an innovative approach to coupling nutrient recycling with low-temperature biological heat generation.

Authored by Anran Li, Xueyi Mai, Sijie Huang, Prithvi Simha, Cees J.N. Buisman, and Wei-Shan Chen, the research investigates how different urine-derived solids can act as nitrogen (N) and phosphorus (P) sources to improve biological wood oxidation (BWO), a meso-thermophilic composting process that simultaneously produces usable heat and nutrient-rich compost.

The study compared three urine-derived formulations — phosphoric acid-dehydrated urine (PDU), oxalic acid-dehydrated urine (ODU), and struvite — and found that PDU performed best, with a 27.5% reduction in wood dry mass after 42 days at 40 °C. Its balanced nutrient composition, gradual urea hydrolysis, and mildly acidic conditions promoted strong microbial and fungal activity, while struvite’s high alkalinity and poor nutrient balance hindered degradation. These results demonstrate that acid-dehydrated urine can act as an effective, sustainable nutrient supplement for composting systems, supporting circular nutrient recovery and bioenergy generation.

We congratulate our WU partners on this forward-thinking contribution that bridges waste valorisation, nutrient circularity, and renewable heat generation — aligning closely with the TEAPOTS vision.