Effect of initialC/Nratio on composting of two-phase olive mill pomace, dairy manure, and straw

Ekinci K., TOSUN İ., Kumbul B. S., Sevik F., Suluk K., BITRAK N. B.

ENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, vol.40, no.2, 2021 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 40 Issue: 2
  • Publication Date: 2021
  • Doi Number: 10.1002/ep.13517
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, PASCAL, Agricultural & Environmental Science Database, Applied Science & Technology Source, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), Biotechnology Research Abstracts, Chemical Abstracts Core, Compendex, Computer & Applied Sciences, Environment Index, Greenfile, INSPEC, Pollution Abstracts
  • Keywords: first-order rate kinetics, relative heat generation, throughput capacity, two-phase olive mill pomace, PROCESSING WASTES, C/N RATIO, BIODEGRADATION, EMISSIONS, SCALE
  • Süleyman Demirel University Affiliated: Yes


Composting plants should be operated at a high degradation rate in order to lower their capital and operational costs. Initial C/N ratio is one of the most influential factors on the composting process. This study aimed to determine the impacts of initial C/N ratio on operational composting parameters of two-phase olive mill pomace with separated dairy manure. Five initial C/N ratios ranging from 29.43 to 43.33 were examined using fifteen 100 L cylindrical reactors. The highest decomposition rate was estimated at 0.02 day(-1)with the C/N ratio of 34.49. The maximum relative heat generation was obtained with the C/N ratio of 36.07. The C/N ratio of approximately equal to 33 reduced the composting cost of process-based total airflow supplied per dry matter and organic matter loss. The maximum throughput capacity was obtained when the compost blend had the C/N ratio of approximately equal to 37.24. It was concluded that operating the composting of two-phase olive mill waste, separated dairy manure, and straw with the boundary of the initial C/N ratios between 33 and 37 was recommended.