Improvement of a grass-clover silage-fed biogas process by the addition of cobalt

  • Jarvis Å
  • Nordberg Å
  • Jarlsvik T
 et al. 
  • 60

    Readers

    Mendeley users who have this article in their library.
  • 60

    Citations

    Citations of this article.

Abstract

Batch assays were performed with samples from a silage-fed mesophilic biogas process accumulating acetate to examine if the addition of single trace elements (iron, nickel, cobalt and molybdenum) or a mixture of trace elements could improve the process. The results from the batch assays led to the addition of cobalt to reach a concentration of 0.2 mg L-1. This made it possible to increase the organic loading rate (OLR) above that in a parallel process not receiving any extra cobalt. Problems with low gas production and decreasing pH were overcome by the daily supply of this single element in small amounts. Acetate conversion to methane was improved, which was confirmed by increased specific methanogenic activity (SMA) with acetate as a substrate. As a consequence, an OLR of 7.0 g VS L-1day-1was achieved at a hydraulic retention time (HRT) of 20 days with an equivalent increase in methane production. Without cobalt addition, an OLR of 5.0 g VS L-1day-1with an HRT of 20 days was reached after 70 weeks operation.

Author-supplied keywords

  • Anaerobic digestion
  • Cobalt
  • Energy crops
  • Silage
  • Specific methanogenic activity
  • Trace elements

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

  • Å Jarvis

  • Å Nordberg

  • T. Jarlsvik

  • B. Mathisen

  • B. H. Svensson

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free