Aqueous Phase from Hydrothermal Liquefaction: Composition and Toxicity Assessment

The main obstacle to the widespread use of hydrothermal liquefaction (HTL) for waste and wet biomass recycling is formation a significant amount highly polluted wastewaters. This paper presents an analysis chemical composition toxicity aqueous phase from HTL (HTL-AP) primary secondary sludge. It was shown that HTL-AP has high level organic pollution (total carbon (TOC) = 4.2–9.6 g/dm3, oxygen demand (COD) 7.9–14.0 BOD5 6.0–8.1 g/dm3) biological traditional test organisms (so dilution ratio, ensuring death no more than 50% (DR50), varied within 64.7–142.2 44.9–81.7 Artemia salina Paramecium caudatum, respectively). An with NMR-spectroscopy method allowed us establish share in aliphatic chains 34.05–41.82% content carboxyl groups aromatic rings 26.42–34.44%. As result, we can conclude components are fatty carboxylic acids their derivatives, acids. aldehydes, ketones, lignin less 8%. Biological treatment lab-scale aerobic reactor turned out be successful, so average COD reduction 67–95%. Sludge industrial water plant (petrochemical sector) microorganism concentration 2.7 g/dm3 used as inoculum. HTP-AP diluted 1:10 tap water. duration process 18 h.