Nevertheless, short induction times were only obtained for wall temperatures exceeding 450 °C. For
this reason the conclusion drawn already from the ignition diagrams (Figure 2) remains valid: There is no
risk of self ignition in the IGCC-CCS fuel system if (a) the oxygen concentration in the diluted fuel is
kept at 3 vol% or below and (b) wall temperatures are kept below 400 °C. Since this agrees with the
conclusion drawn for the UFL, IGCC-CCS fuel system conditions with oxygen concentrations below 3
vol% and wall temperatures below 400 °C can in general be considered safe.