Correlations between the Composition of Liquid Fraction of Full-Scale Digestates and Process Conditions

Energies

Afifi Akhiar¹  Audrey Battimelli¹  Felipe Guilayn¹  Hélène Carrère¹  Michel Torrijos¹  AbdHalim Shamsuddin² 

[1] INRAE, Université de Montpellier, LBE, 102 Avenue des Etangs, 11100 Narbonne, France;Institute of Sustainable Energy (ISE), Universiti Tenaga Nasional, Jalan IKRAM-UNITEN, Kajang 43000, Selangor, Malaysia;

关键词: anaerobic digestion;    solid waste;    organic compound;    solid–liquid separation;    liquid phase;    digestate treatment;   

DOI  :  10.3390/en14040971

来源: DOAJ

【 摘 要 】

Fast development of centralized agricultural biogas plants leads to high amounts of digestate production. The treatment and disposal of liquid fractions after on-site digestate solid–liquid separation remains problematic due to their high organic, nutrient and aromatic contents. This work aims to study the variability of the remaining compounds in the digestate liquid fractions in relation to substrate origin, process parameters and solid–liquid separation techniques. Twenty-nine digestates from full-scale codigestion biogas plants and one waste activated sludge (WAS) digestate were collected and characterized. This study highlighted the combined effect of the solid–liquid separation process and the anaerobic digestion feedstock on the characteristics of liquid fractions of digestates. Two major clusters were found: (1) liquid fractions from high efficiency separation process equipment (e.g., centrifuge and others with addition of coagulant, flocculent or polymer) and (2) liquid fractions from low efficiency separation processes (e.g., screw press, vibrating screen and rotary drum), in this latter case, the concentration of chemical oxygen demand (COD) was associated with the proportion of cow manure and energy crops at biogas plant input. Finally, SUVA₂₅₄, an indicator for aromatic molecule content and the stabilization of organic matter, was associated with the hydraulic retention time (HRT).

【 授权许可】

Unknown