Anaerobic Digestate Nutrient Recycling for Hydroponic Fertilizer Applications

Overview

This research investigates the use of anaerobic digestate—the nutrient-rich byproduct of biogas production—as a fertilizer source for soil-less culture systems such as hydroponics. Conventional hydroponic nutrient solutions rely exclusively on dissolved inorganic salts, avoiding organic content. This work challenges that paradigm by evaluating whether digestate from various organic wastes can supply both essential nutrients and beneficial bioactive compounds to hydroponically grown plants. The research also explores the dynamics of nutrient flow during anaerobic digestion and the pathways by which bioactive molecules are generated, supporting circular-economy approaches to organic waste management.

Technical specifications

Core research capabilities:

• Chemical composition profiling of biogas slurry using gas chromatography/mass spectrometry (GC/MS) to identify and classify bioactive molecular ingredients
• Extraction and characterization of functional heterocyclic molecules, categorized into N-Heterocycles and O-Heterocycles
• Antibacterial efficacy testing against soil-borne pathogens including Fusarium oxysporum and Rhizoctonia using digestate at varying concentrations
• Evaluation of digestate derived from multiple feedstocks (chicken manure, pig manure) and processing methods (flocculation, membrane concentration)
• Assessment of nutrient variation throughout the anaerobic digestion process to map nutrient flow from waste inputs to digestate outputs
• Fertilizer potential evaluation of treated anaerobic digestate in hydroponic gardening applications

Key findings to date:

• Inhibiting effects against pathogenic fungi are linked to both microbial and chemical factors, with efficacy increasing at higher digestate concentrations

Technology readiness level

The research is at an early-to-mid stage of development. Initial validation has been completed through antibacterial experiments on key fungal pathogens, demonstrating dose-dependent inhibition effects. Future work will involve collecting and digesting diverse organic wastes, tracking nutrient flow during digestion, characterizing bioactive compound generation pathways, and evaluating the fertilizer potential of digestate in hydroponic systems. The platform is positioned for collaborative development toward practical hydroponic fertilizer formulations derived from organic waste streams.