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

作者：Gruber Thomas^*; Scharler Robert; Obernberger Ingwald

来源：Biomass and Bioenergy, 2015, 79: 145-154.

DOI：10.1016/j.biombioe.2015.02.024

• Biomass combustion
• Combined heat and power generation (CHP)
• Corrosion
• Model
• Wood chips

To gain reliable data for the development of an empirical model for the prediction of the local high temperature corrosion potential in biomass fired boilers, online corrosion probe measurements have been carried out. The measurements have been performed in a specially designed fixed bed/drop tube reactor in order to simulate a superheater boiler tube under well-controlled conditions. The investigated boiler steel 13CrMo4-5 is commonly used as steel for superheater tube bundles in biomass fired boilers. Within the test runs the flue gas temperature at the corrosion probe has been varied between 625 degrees C and 880 degrees C, while the steel temperature has been varied between 450 degrees C and 550 degrees C to simulate typical current and future live steam temperatures of biomass fired steam boilers. To investigate the dependence on the flue gas velocity, variations from 2 m.s(-1) to 8 m.s(-1) have been considered. The empirical model developed fits the measured data sufficiently well. Therefore, the model has been applied within a Computational Fluid Dynamics (CFD) simulation of flue gas flow and heat transfer to estimate the local corrosion potential of a wood chips fired 38 MW steam boiler. Additionally to the actual state analysis two further simulations have been carried out to investigate the influence of enhanced steam temperatures and a change of the flow direction of the final superheater tube bundle from parallel to counter-flow on the local corrosion potential.

• 出版日期2015-8