TY - BOOK

T1 - Impact on High Temperature Corrosion in a Thermal Cracking Reactor of Post-Consumer Plastics

AU - Nimmervoll, Manuela

N1 - embargoed until 25-04-2027

PY - 2022

Y1 - 2022

N2 - In the course of this PhD thesis the high temperature corrosion behavior of commonly used construction materials was evaluated to find the most suitable reactor material for a thermal cracking process of post-consumer plastics. Materials ranged from low alloyed ferritic Fe-Cr steels up to high alloyed austenitic Fe-Cr-Ni steels and were, in general, tested between 420 and 580 °C, at laboratory scale. Test gas atmospheres contained 3.8 vol% HCl and a varying amount of H2S, which was either 0.02 vol%, 0.2 vol% or 2 vol%. Thus, the impact of different H2S levels on the high temperature corrosion behavior of various alloys in reducing HCl containing atmospheres could be studied. Tested materials were investigated by means of metallography, SEM/EDX and XRD measurements. In addition, the corrosion rates of the alloys were determined after the corrosion experiments. Furthermore, several thermodynamic calculations were performed with the software Fact Sage 8.0. Whit these data, high temperature corrosion mechanisms in reducing atmospheres containing HCl (3.8 vol%) and varying amounts of H2S (0.02 vol% - 2 vol%) were developed for ferritic and austenitic alloys at different temperatures. In general, an increase of the H2S content in the given chlorine containing atmospheres lead to an accelerated corrosion of all materials. However, at lower testing temperatures this effect disappeared and also the ferritic material, which in general revealed the poorest corrosion resistance, showed a comparable performance to the austenitic materials.

AB - In the course of this PhD thesis the high temperature corrosion behavior of commonly used construction materials was evaluated to find the most suitable reactor material for a thermal cracking process of post-consumer plastics. Materials ranged from low alloyed ferritic Fe-Cr steels up to high alloyed austenitic Fe-Cr-Ni steels and were, in general, tested between 420 and 580 °C, at laboratory scale. Test gas atmospheres contained 3.8 vol% HCl and a varying amount of H2S, which was either 0.02 vol%, 0.2 vol% or 2 vol%. Thus, the impact of different H2S levels on the high temperature corrosion behavior of various alloys in reducing HCl containing atmospheres could be studied. Tested materials were investigated by means of metallography, SEM/EDX and XRD measurements. In addition, the corrosion rates of the alloys were determined after the corrosion experiments. Furthermore, several thermodynamic calculations were performed with the software Fact Sage 8.0. Whit these data, high temperature corrosion mechanisms in reducing atmospheres containing HCl (3.8 vol%) and varying amounts of H2S (0.02 vol% - 2 vol%) were developed for ferritic and austenitic alloys at different temperatures. In general, an increase of the H2S content in the given chlorine containing atmospheres lead to an accelerated corrosion of all materials. However, at lower testing temperatures this effect disappeared and also the ferritic material, which in general revealed the poorest corrosion resistance, showed a comparable performance to the austenitic materials.

KW - Hochtemperaturkorrosion

KW - HCl

KW - H2S

KW - ferritischer Stahl

KW - austenitischer Stahl

KW - High temperature corrosion

KW - HCl

KW - H2S

KW - ferritic steel

KW - austenitic steel

M3 - Doctoral Thesis

ER -