Gas cleaning with hot char beds studied by stable isotopes

TY - JOUR

T1 - Gas cleaning with hot char beds studied by stable isotopes

AU - Egsgaard, H.

AU - Ahrenfeldt, J.

AU - Ambus, Per Lennart

AU - Schaumburg, K.

AU - Henriksen, U. B.

PY - 2014/5/1

Y1 - 2014/5/1

N2 - The chemistry taking place in a high temperature char bed used for binding aromatic tar compounds has been studied in detail. 13C labelled tar compounds were used to trace the incorporation into the char bed using isotope ratio mass spectrometry (IRMS) and GC-MS. Furthermore, compounds labelled with 2H (deuterium) were used to support proposed reaction mechanisms. It was found that at 700-800 °C the aromatic tar compounds bind irreversibly to the char by a radical reaction and, hence, become an integrated part of the char. Thermally induced reactions may occur prior to the binding reaction. The findings explain the tar reducing properties of the char bed in two-stage gasifiers. A living char bed for hot gas cleaning is discussed.

AB - The chemistry taking place in a high temperature char bed used for binding aromatic tar compounds has been studied in detail. 13C labelled tar compounds were used to trace the incorporation into the char bed using isotope ratio mass spectrometry (IRMS) and GC-MS. Furthermore, compounds labelled with 2H (deuterium) were used to support proposed reaction mechanisms. It was found that at 700-800 °C the aromatic tar compounds bind irreversibly to the char by a radical reaction and, hence, become an integrated part of the char. Thermally induced reactions may occur prior to the binding reaction. The findings explain the tar reducing properties of the char bed in two-stage gasifiers. A living char bed for hot gas cleaning is discussed.

U2 - 10.1016/j.jaap.2014.02.019

DO - 10.1016/j.jaap.2014.02.019

M3 - Journal article

SN - 0165-2370

VL - 107

SP - 174

EP - 182

JO - Journal of Analytical and Applied Pyrolysis

JF - Journal of Analytical and Applied Pyrolysis

ER -