title: Hydrothermal carbonization of biomass from landscape management - Influence of process parameters on soil properties of hydrochars.
abstract: Besides pyrolysis the technology of hydrothermal carbonization (HTC) is tested to produce hydrochars for soil improvement. The chemical and physical properties of the hydrochars mainly depend on the feedstock and the process parameters reaction time and process temperature. Systematic investigations on the influences of these process parameters on soil properties of hydrochars like water holding capacity (WHC) and cation exchange capacity (CEC) are missing. In this study, a rush-rich biomass was carbonized within defined HTC process conditions under variation of reaction time and process temperature to produce hydrochars. Analysis of WHC, CEC, the elemental composition and Fourier-transform infrared spectroscopy (FT-IR) were performed to evaluate the influence of HTC process conditions on the pedological hydrochar properties. The results indicated that at increasing reaction severity (reaction time and process temperature) WHC and CEC decreased as well as the elemental O/C ratio. The decrease of WHC and CEC is based on the decrease of the hydrochar surface polarity. However, even the lowest WHC and CEC of investigated hydrochars still exceeded those of pure quartz sand by factors of 5-10. An application of hydrochars produced at severe HTC conditions could improve WHC and CEC of sandy soils. This has to be investigated in further studies.
authors.affiliation: Institute of Biology and Environmental Science, Carl von Ossietzky University of Oldenburg, Ammerländer Heerstr. 114-118, 26129, Oldenburg, Germany. Electronic address: michael.roehrdanz@gmx.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Röhrdanz
authors.affiliation: Department of Engineering Sciences and Computer Science, University of Applied Sciences Osnabrück, Albrechtstr. 30, 49076, Osnabrück, Germany.
authors.forename: Tammo
authors.initials: T
authors.lastname: Rebling
authors.affiliation: Institute of Technical Chemistry, Carl von Ossietzky University of Oldenburg, Carl-von-Ossietzky-Str. 9-11, 26111 Oldenburg, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Ohlert
authors.affiliation: Institute of Biology and Environmental Science, Carl von Ossietzky University of Oldenburg, Ammerländer Heerstr. 114-118, 26129, Oldenburg, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Jasper
authors.affiliation: Institute of Technical Chemistry, Carl von Ossietzky University of Oldenburg, Carl-von-Ossietzky-Str. 9-11, 26111 Oldenburg, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Greve
authors.affiliation: Institute of Biology and Environmental Science, Carl von Ossietzky University of Oldenburg, Ammerländer Heerstr. 114-118, 26129, Oldenburg, Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Buchwald
authors.affiliation: Department of Engineering Sciences and Computer Science, University of Applied Sciences Osnabrück, Albrechtstr. 30, 49076, Osnabrück, Germany.
authors.forename: Petra
authors.initials: P
authors.lastname: von Frieling
authors.affiliation: Institute of Technical Chemistry, Carl von Ossietzky University of Oldenburg, Carl-von-Ossietzky-Str. 9-11, 26111 Oldenburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Wark
mesh_terms: D018533:Biomass; D002244:Carbon / Q000737:chemistry*; D006358:Hot Temperature; D012987:Soil / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D012987:Soil; D002244:Carbon
keywords: Biochar; Cation exchange capacity; Infrared spectroscopy; Soil improvement; Water holding capacity