Investigation of the corrosion behaviour of 13CrMo4–5 for biomass fired boilers with coupled online corrosion and deposit probe measurements

Application of an empirical model in CFD simulations to predict the local high temperature corrosion potential in biomass fired boilers

“…Therefore, superheater 3 is not Fig. 6 e Trend of measured corrosion rates as a function of flue gas velocity and temperature (markers) in comparison to the values of the empirical function (lines) developed [10]. Explanation: v FG … flue gas velocity; T FG … flue gas temperature; the steel temperature has been kept constant at 480 ± 0.5 C. equally passed through by the flue gas.…”

“…[10] no chlorine or traces of a molten layer could be found neither in the deposit nor the corrosion layer of the corrosion probe by means of SEM/EDX analyses. Therefore, it is suggested that the main corrosion mechanism prevailing is the oxidation of the low alloy steel by molecular oxygen.…”

“…The aim of the work presented is the application of a newly developed empirical model [10] together with a CFD simulation of flow and heat transfer to calculate the local high temperature corrosion potential in a biomass fired steam boiler. In addition to the actual state analysis the influences of enhanced steam temperatures as well as a change of the flow direction of the final superheater tube bundle from parallel to counter-flow on the local corrosion potential is investigated within this work.…”

“…The optimized coefficients of the empirical function are listed in Table 6. 4 e Plot of the measured corrosion rates (markers) and the empirical function developed (lines) as a function of the flue gas temperature for several steel temperatures [10]. Explanation: T S … steel temperature; T FG … flue gas temperature; the flue gas velocity has been kept constant to 2.8 ± 0.5 m·s ¡1 .…”

“…Schematic view of the combined packed bed/drop tube reactor with relevant units and measurement ports[10]. Picture of the biomass fuel used for the test runs.…”