Recent research published in “Results in Engineering” reveals significant advancements in understanding how hydrothermal treatment can transform phosphorus in swine manure, a common agricultural waste. Led by Shiyu Xie from the State Key Laboratory of Nutrient Use and Management at China Agricultural University, the study provides insights into the morphological distribution and transformation mechanisms of phosphorus during hydrothermal carbonization (HTC).
Phosphorus is a critical nutrient for plant growth, but its presence in waste products like swine manure poses environmental challenges. This research investigates how the severity of hydrothermal reactions affects the solid and liquid phases of phosphorus. The findings indicate that as the reaction severity increases, particularly beyond a certain threshold (LnR0 > 9.41), inorganic phosphorus and metal ions transition from the liquid to the solid phase. This shift is crucial because it implies that more phosphorus can be stabilized in a solid form, making it easier to recycle and utilize in agriculture.
The study highlights that over 90% of the total phosphorus content can be fixed in solid form through optimized hydrothermal processes. Notably, Xie points out, “The hydrothermal carbonization can enhance the reuse efficiency of phosphorus in wastes, which is essential for sustainable agricultural practices.” The research also identified hydroxyapatite as the predominant phosphorus fraction in the solid-phase products, accounting for over 60% of the phosphorus content, alongside magnesium ammonium phosphate components.
For the energy sector, these findings present commercial opportunities in waste-to-energy technologies. By improving the efficiency of phosphorus recovery from agricultural waste, companies can not only contribute to environmental sustainability but also tap into the growing market for recycled fertilizers. The ability to convert swine manure into valuable resources aligns with global efforts to reduce waste and promote circular economy practices.
This research underscores the potential of hydrothermal carbonization as a viable solution for managing agricultural waste while enhancing nutrient recovery. As the demand for sustainable agricultural practices increases, the techniques developed by Xie and his team could play a pivotal role in transforming how we view and utilize waste materials in the energy and agricultural sectors.
