Anaerobic co-digestion of oil-extracted spent coffee grounds with various wastes: Experimental and kinetic modeling studies

Atelge M. R., Mohamed Atabani A., Abut S., Kaya M., Eskicioglu C., Semaan G., ...More

BIORESOURCE TECHNOLOGY, vol.322, 2021 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 322
  • Publication Date: 2021
  • Doi Number: 10.1016/j.biortech.2020.124470
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, Compendex, EMBASE, Environment Index, Food Science & Technology Abstracts, Geobase, INSPEC, MEDLINE, Pollution Abstracts, Veterinary Science Database, Civil Engineering Abstracts
  • Keywords: Defatted spent coffee grounds, Oil extraction, Anaerobic digestion, Kinetic study, Biofuels, MICROALGAE, BIOMASS
  • Erciyes University Affiliated: Yes


The effect of oil extraction from spent coffee grounds as a pre-treatment strategy prior to anaerobic digestion besides assessing the feasibility of defatted spent coffee grounds co-digestion with spent tea waste, glycerin, and macroalgae were examined. Mesophilic BMP tests were performed using defatted spent coffee grounds alongside four co-substrates in the ratio of 25, 50, and 75%, respectively. The highest methane yield was obtained with the mono-digestion of defatted spent coffee grounds with 336 +/- 7 mL CH4/g VS and the yield increased with the increase in the mass ratio of defatted spent coffee grounds during co-digestion. Moreover, defatted spent coffee grounds showed the highest VS and TS removal at 35.5% and 32.1%, respectively and decreased thereafter. Finally, a linear regression model for the interaction effects between substrates was demonstrated and showed that distinctly mixing defatted spent coffee grounds, spent coffee grounds, and spent tea waste outperforms other triple mixed substrates.