Comparison of CSTR and UASB reactor configuration for the treatment of sulfate rich wastewaters under acidifying conditions

S.I.C. Lopes, C. Dreissen, M.I. Capela, P.N.L. Lens

Research output: Contribution to journalArticleAcademicpeer-review

19 Citations (Scopus)

Abstract

The effects of lowering the operational pH from 6 to 5 on mesophilic (30 degrees C) sulfate reduction during the acidification of sucrose at an organic loading rate of 5 gCOD(1(reactor)d)(-1) and at a COD/SO42- ratio of 4 were evaluated in a CSTR and in a UASB reactor. The HRT was 24 h and 10 h, respectively. Acidification was complete in both reactors at pH 6 and the lowering of the operational pH to 5 did not affect the acidification efficiency in the CSTR but decreased the acidification efficiency of the UASB to 72%. The decrease to pH 5 caused an increase in the effluent butyrate and ethanol concentrations in both reactors. Lowering the pH from 6 to 5 caused a decrease in sulfate reduction efficiencies in both reactors, from 43% to 25% in the CSTR and from 95% to 34% in the UASB reactor. The acidification and sulfate reduction efficiencies at pH 5 could be increased to 94% and 67%, respectively, by increasing the HRT of the UASB reactor to 24 h. (
Original languageEnglish
Pages (from-to)471-479
JournalEnzyme and Microbial Technology
Volume43
Issue number7
DOIs
Publication statusPublished - 2008

Keywords

  • granular sludge reactors
  • volatile fatty-acids
  • anaerobic-digestion
  • acidogenic phase
  • waste-water
  • ph 6
  • hydrogen-production
  • blanket reactors
  • mixed culture
  • fermentation

Fingerprint Dive into the research topics of 'Comparison of CSTR and UASB reactor configuration for the treatment of sulfate rich wastewaters under acidifying conditions'. Together they form a unique fingerprint.

Cite this