title: Impact of bioaugmentation by compost on the performance and ecology of an anaerobic digester fed with energy crops.
abstract: The influence of compost as inoculum during continuous anaerobic digestion of fodder beet silage was studied over 330 days. Two simultaneously driven mesophilic fermentors (Inoc-1/Inoc-2) were inoculated with manure and sewage sludge. Only the digester Inoc-2 was inoculated additionally with compost. After 160 days fermentor Inoc-2 reached a hydraulic retention time (HRT) around 15 days whereas Inoc-1 remained at a HRT of 40d. After changing the substrate feed from one to three times a day both digesters stabilised at a shorter HRT; Inoc-2 at 10 days and Inoc-1 around 20 days. An additional inoculation of fermentor Inoc-1 by compost shortened the HRT to 10 days and revealed a minor increased gas production of about 6%. Fluorescence in situ hybridization indicated that probably an archaeal population shift was responsible for the observed stimulations. An addition of compost induced a methanogenic community change towards hydrogenotrophic methanogens.
authors.affiliation: Hamburg University of Applied Sciences, Laboratory of Applied Microbiology, Hamburg, Germany. lukas.neumann@haw-hamburg.de
authors.forename: L
authors.initials: L
authors.lastname: Neumann
authors.forename: P
authors.initials: P
authors.lastname: Scherer
mesh_terms: D001421:Bacteria, Anaerobic / Q000378:metabolism*; D027461:Beta vulgaris / Q000382:microbiology*; D019149:Bioreactors / Q000382:microbiology*; D003246:Conservation of Energy Resources / Q000379:methods*; D018556:Crops, Agricultural / Q000382:microbiology*; D017753:Ecosystem; D012988:Soil Microbiology