Use of bio-based carbon materials for improving biogas yield and digestate stability

Research output: Contribution to journalArticleScientificpeer-review

Researchers

  • Sining Yun
  • Wen Fang
  • Tingting Du
  • Xieli Hu
  • Xinlei Huang
  • Xue Li
  • Chen Zhang
  • Peter D. Lund

Research units

  • Xi'an University of Architecture and Technology

Abstract

Additives can effectively improve the anaerobic digestion performance. In this work, we have investigated the effect of seven carbon materials as additives on the biogas yield, the total chemical oxygen demand (CODt) removal rate and the digestate stability. These carbon materials have larger Brunauer-Emmett-Teller (BET) specific surface area of 580–824 m2/g and uniform pore volume of 0.54–0.64 m3/g. Adding carbon into AD systems can significantly improve the biogas yield (380–502 mL/g TS) and CODt removal rate (51.39%–67.81%) by 30–70% and 74–129%, respectively, compared to the reference system (CK, control check, 294 mL/g TS and 29.55%). Carbon additives with higher BET specific surface area are responsible for improving the AD efficiency by providing sites where substrate accumulate and thereby promote high localized substrate concentrations. Significant improvement in the AD efficiency can be microscopically attributed to the methanogenesis promoted by the conductive carbon that can facilitate direct interspecies electron transfer between fermenting bacteria and methanogens, accelerating syntrophic acetate metabolism and biogas yield. These carbon materials developed are excellent additives in AD for improving the biogas yield, CODt degradation, the stability and the fertilizer utilization of the digestate. These increased properties lead to more efficient use of the waste feedstock in biogas systems.

Details

Original languageEnglish
Pages (from-to)898-909
Number of pages12
JournalEnergy
Volume164
Publication statusPublished - 1 Dec 2018
MoE publication typeA1 Journal article-refereed

    Research areas

  • Additive, Anaerobic digestion, Bio-based carbon materials, Biogas yield, CODt removal rate, Digestate stability

ID: 28341112