Title:
Erroneous Quantification of CO and NH3 by FTIR in the Presence of H2 and H2O in Biomass Steam Gasification Syngas
Author(s):
Defoort, F., Thiery, S., Puech, A.
Document(s):
Paper
Abstract:
The objective of this study is to investigate the effect of H2 and H2O, which are some of the main species present in the gas phase during steam gasification of biomass, in the quantification of CO and NH3 by FTIR (Fourier Transform Infra Red spectrometry). By comparing micro¬Gas Chromatography (.GC) coupled with Thermal Conductivity Detectors (TCD) and FTIR for CO measurements, a matrix effect of H2 on CO quantification by FTIR was observed. This matrix effect was not detected on the other gaseous species. Similarly, a matrix effect of H2O on CO and NH3 quantification was observed. The scientific reason of this effect comes from gas/gas interaction when partial pressures are high (called collisional broadening). From the results of this study, it appears that H2 and H2O can induce an important error (close to 50%) on the CO and NH3 quantification by FTIR if they are not taken into account in the calibration method. We proposed a mathematical model which can be used with an Excel sheet. It has been validated on outlet gas from biomass gasification experiments in CEA pilots. This model is similar to the so¬called coefficients of "cross-correction" encountered in some FTIR gas calibration software. Now, the main gaseous species of Syngas as CO, CO2, H2O and the NH3 pollutant can be quantified on line by FTIR in a pilot gasifier with a good confidence.
Keywords:
biomass, gasification, measurement, modelling, syngas, FTIR
Topic:
R&D on Biomass Conversion Technologies for Heating, Electricity and Chemicals
Subtopic:
Gasification for synthesis gas production
Event:
20th European Biomass Conference and Exhibition
Session:
2BV.2.37
Pages:
1097 - 1103
ISBN:
978-88-89407-54-7
Paper DOI:
10.5071/20thEUBCE2012-2BV.2.37
Price:
FREE
