Ash Particle Hardness and Effect on Material

[Operator Mike]

RE: Hot corrosion/erosion of metal
How does one go about testing the effect of an ash particle against a steel surface? Particle at high velocity etc. We are piloting a furnace with high phosphorous content biomass fuel and one with High-P biomass+lime. Lime addition affects SO2-SO3 content in flue gas to prevent downstream corrsoion in cold end of unit. Other benefits might include softening of ash particle.

What scientific methods exist for testing particle effect at high velocity against a steel surface? Would like to test ash particle and lime ash particle for differences. ASTM methods would be nice, ash particles are varied in size from 2-500 microns, smaller particles edges are jagged compared to larger particles. we have tried ASTM G65 with limited success. Nozzle clogging was an issue.

[Gordon]

Hi Mike

Quote:ASTM G 76 - 1983 - Standard Practice for Conducting Erosion Tests by Solid Particle Impringment using Gas Jets.

I think you will need to develop your own specialised test to mimic as close as possible your specific conditions ie similar particle velocity, temperature and attack angle etc. Testing using simple erosion testing rig (grit blaster) at ambient temperature may give misleading results compared to that of elevated temperatures. A hot erosion test rig (similar to a thermal spray system) - particles entrained in a hot gas stream.

Copied from my post in your previous thread "Hot corrosion/erosion of metal"

Feeding material into blast jet in a controllable and consistent manner may well be the most challenging part.