Characterization of products from hydrothermal carbonization of orange pomace including anaerobic digestibility of process liquor

Bioresour Technol. 2015 Nov:196:35-42. doi: 10.1016/j.biortech.2015.06.115. Epub 2015 Jun 29.

Abstract

In this study, the effect of the temperature and reaction time on hydrothermal carbonization (HTC) of orange pomace was investigated. In addition, a set of anaerobic batch tests were performed to determine the resulting biogas and methane potential of the spent liquor. Hydrochar yields followed a decreasing trend with the increasing temperature, whereas reaction time had no considerably effect on the yield. The evolution of the H/C and O/C atomic ratios from the raw material to the hydrochars suggested that dehydration reactions prevail during HTC. The hydrochars tended to become enriched in Ca, Mg and P minerals by increasing HTC temperature. The heavy metal contents in hydrochars were found below limits and no PAH compound was detected. Anaerobic digestion tests showed that the aqueous phase from HTC can be used as feedstocks for biogas production.

Keywords: Anaerobic digestion; Biogas; Hydrochar; Hydrothermal carbonization; Orange pomace.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anaerobiosis
  • Biofuels / analysis
  • Biological Oxygen Demand Analysis
  • Carbon / chemistry*
  • Charcoal / chemistry
  • Citrus sinensis / chemistry*
  • Metals, Heavy / analysis
  • Temperature*
  • Time Factors
  • Waste Disposal, Fluid / methods*
  • Waste Products / analysis*
  • Water*

Substances

  • Biofuels
  • Metals, Heavy
  • Waste Products
  • biochar
  • Water
  • Charcoal
  • Carbon