Investigation of the effects of different conductive materials on the anaerobic digestion
- 80 Downloads
In recent years, the efforts of enhancement of the transformation of organic matter into methane have intensified and direct interspecies electron transfer (DIET) mechanisms have great importance in this regard. In this study, magnetite, graphite powder, activated carbon and iron (II) sulfate were used to investigate DIET mechanisms during the conversion of glucose into methane. Obtained methane gas measurements at the end of the 30-day incubation period (37 ± 1 °C) were evaluated with the modified Gompertz model, first-order kinetic model and two-stage first-order kinetic model. Maximum total and soluble COD removal efficiencies were observed in the magnetite-added R2 reactor (73.75% and 90.68%, respectively). While there was no significant difference in terms of cumulative methane gas measurements, a significant decrease was observed in the lag phase time for the magnetite-added R2 reactor (reduced by half) with regard to the modified Gompertz model. According to the first-order kinetic model, the maximum conversion rate of glucose into methane and the peak methane production rate were observed in the graphite powder-added R3 reactor (k = 0.1744 day−1 and 93 mL/day). According to the two-stage kinetic model, the maximum methanation rate was observed in the magnetite-added R2 reactor (k2 = 0.7223 day−1). The sludge in the magnetite-added R2 reactor has best settleability (SVI = 53.4 mL/g).
KeywordsAnaerobic treatment DIET Glucose Conductive materials
The authors wish to thank all who assisted in conducting this work.
Within the scope of this study, no any funding was received.
Compliance with ethical standards
Conflict of interest
The author declares that he has no conflict of interest.
- Chernicharo CAL, von Sperling M, Chernicharo CAL (2007) Anaerobic reactors. IWA Publishing, LondonGoogle Scholar
- Eaton AD, American Public Health Association, American Water Works Association, Water Pollution Control Federation (eds) (2005) Standard methods for the examination of water and wastewater, 21, centennial edn. American Public Health Assocication, WashingtonGoogle Scholar
- Khanal S (2011) Anaerobic biotechnology for bioenergy production: principles and applications. Wiley, SomersetGoogle Scholar
- Suanon F, Sun Q, Li M et al (2017) Application of nanoscale zero valent iron and iron powder during sludge anaerobic digestion: impact on methane yield and pharmaceutical and personal care products degradation. J Hazard Mater 321:47–53. https://doi.org/10.1016/j.jhazmat.2016.08.076 CrossRefGoogle Scholar
- Zhao Z, Zhang Y, Li Y et al (2017b) Potentially shifting from interspecies hydrogen transfer to direct interspecies electron transfer for syntrophic metabolism to resist acidic impact with conductive carbon cloth. Chem Eng J 313:10–18. https://doi.org/10.1016/j.cej.2016.11.149 CrossRefGoogle Scholar