Hydrogen gas production from waste anaerobic sludge by electrohydrolysis: Effects of applied DC voltage

Kargi F., Catalkaya E., Uzuncar S.

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, cilt.36, sa.3, ss.2049-2056, 2011 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 36 Sayı: 3
  • Basım Tarihi: 2011
  • Doi Numarası: 10.1016/j.ijhydene.2010.11.087
  • Dergi Adı: INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.2049-2056
  • Anahtar Kelimeler: Hydrogen gas, COD removal, DC voltage, Electrohydrolysis, Waste sludge, DARK FERMENTATION EFFLUENT, HYDROLYZED WHEAT-STARCH, FATTY-ACID VFA, BIOHYDROGEN PRODUCTION, RHODOBACTER-SPHAEROIDES, MICROBIAL-PRODUCTION, PHOTO-FERMENTATION, H-2 PRODUCTION, SUBSTRATE, CULTURE
  • Dokuz Eylül Üniversitesi Adresli: Evet

Özet

Waste anaerobic sludge was subjected to different DC voltages (0.5-5 V) for hydrogen gas production by using aluminum electrodes and a DC power supply. Effects of applied DC voltage on the rate and extent of hydrogen gas production were investigated. The highest cumulative hydrogen production (2775 ml), daily hydrogen gas formation (686.7 ml d(-1)), hydrogen yield (96 ml H-2 g(-1) COD) and percent hydrogen (94.3%) in the gas phase were obtained with 2 V DC voltage. Energy conversion efficiency (H-2 energy/electrical energy) also reached the highest level (74%) with 2 V DC voltage application. Control experiments with no voltage application to the sludge yielded almost the same level of COD removal, but no hydrogen gas production. Voltage application to water resulted in much lower hydrogen gas production as compared to sludge indicating negligible electrolysis of water. The results indicated that the sludge was naturally decomposed by the active cells removing COD and releasing hydrogen ions to the medium which reacted with the electrons provided by DC current to produce hydrogen gas. Hydrogen gas production from electrohydrolysis of waste sludge was found to be a fast and effective method with high energy efficiency. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.