Effect of temperature and organic loading rate on siphon-driven self-agitated anaerobic digestion performance for food waste treatment

Waste Manag. 2018 Apr:74:150-157. doi: 10.1016/j.wasman.2017.12.016. Epub 2017 Dec 18.

Abstract

The effects of organic loading rate (OLR) and operating temperature on the performance of siphon-driven self-agitated anaerobic reactor (SDSAR) in an on-site food waste (FW) treatment system were investigated. Two reactors were operated in parallel for comparison between mesophilic condition (35 ± 1 °C) and thermophilic condition (55 ± 1 °C). With HRT above 15 d and OLR below 4.8 kg-COD/m3/d, relatively high COD removal in the range of 84.5-92.3% was obtained in both reactors. The limits of the loading capacity of the mesophilic SDSAR were observed when OLR was further increased to 7.3 kg-COD/m3/d by shortening HRT. Blocking and gas production reduction occurred and COD removal decreased sharply to 75.9% in the mesophilic reactor. In contrast, the thermophilic reactor can be operated at this OLR with satisfactory COD removal and biogas production. Furthermore, at OLR of 14.4 kg-COD/m3/d, the COD removal was maintained as high as 87.5% in the thermophilic reactor. The conversion of influent COD to methane was maintained above 80% at all the OLR applied in both reactors. The results of this study indicated that thermophilic SDSAR is preferred for the on-site FW treatment.

Keywords: Biogas; Food waste (FW); Mesophilic; Siphon-driven self-agitated anaerobic reactor (SDSAR); Thermophilic.

MeSH terms

  • Anaerobiosis*
  • Biofuels
  • Bioreactors
  • Food*
  • Methane
  • Solid Waste
  • Temperature
  • Waste Disposal, Fluid*

Substances

  • Biofuels
  • Solid Waste
  • Methane