Title:
An Economic Perspective of Viable Solutions for Nutrient Recovery from Food Waste Digestate: A Dual Approach Utilizing Struvite Precipitation and Natural Adsorbents
Author(s):
Arellano Yasaca, D.V., Chu, C.-Y.
Document(s):
Paper
Poster
Abstract:
Food waste (FW) poses a significant global challenge, with billions of tonnes disposed of annually, causing severe environmental and economic issues. Anaerobic digestion (AD) is commonly used to convert FW into biogas and digestate. However, AD produces a nutrient-rich liquid digestate (LFD) that presents environmental risks and resource recovery opportunities. This work analyzes our two previously studied nutrient recovery technologies, struvite precipitation and ammonium adsorption using natural rocks. These technologies were applied to LFD from a municipal AD plant in Taiwan. Drawing upon and synthesizing those findings, each method's operational parameters and removal efficiencies were evaluated, focusing on their optimization and the economic feasibility in a full-scale application. When optimized, struvite precipitation achieved up to 86% phosphorus and 75% nitrogen removal, while ammonium adsorption reached 64% removal. A case study at the Waipu AD plant evaluated the economic feasibility of both methods. Despite higher operational costs, struvite precipitation generated revenue from fertilizer sales, covering 94% of adsorption costs. In contrast, ammonium adsorption offered a low-cost, decentralized approach for nutrient-rich soil amendments. The findings provide a replicable framework for nutrient recovery in biogas plants and inform future policy, scale-up efforts, and integration with low-carbon systems.
Keywords:
anaerobic digestion, digestate, adsorbent, food waste, circular economy, fertilizers
Topic:
Biomass Conversion to Biomaterials and Chemicals
Subtopic:
Processes for biomaterials and bio-based chemicals
Event:
33rd European Biomass Conference and Exhibition
Session:
6BV.2.20
Pages:
1118 - 1124
ISBN:
978-88-89407-25-7
Paper DOI:
10.5071/33rdEUBCE2025-6BV.2.20
Price:
FREE
