Superior Erosion Resistance on Boiler Tubes
NanoSteel coating provides superior erosion and corrosion resistance for reducing tube failure
Waste coal is a low energy value discard that has accumulated for more than a century at anthracite and bituminous coal mines in the Northeast USA. Since the early 1990s, coal fired power plants near these mines have been configured to burn this inexpensive fuel source in circulating fluidized bed (CFB) combustion boilers.
For every 100 tons of waste coal burned, more than 60 tons of fly ash, containing chemicals such as mercury and sulfur, is produced along with emissions containing very fine nitrogen oxide particles. Plant operators feed limestone into the combustor to control the chemicals and introduce ammonia to reduce nitrogen oxide emissions. The result is erosion and corrosion damage that causes boiler tube failures and costly unscheduled outages.
Inside a CFB boiler at a coal fired power plant in Pennsylvania, a thermal spray coating field trial comparison was conducted on a section of boiler tubes where the most severe erosion damage occurs. A NanoSteel SHS TWAS coating was applied to a 7’ x 5’ section of boiler tubes between two LMC Armacor™ thermal spray coatings of equal size.
When the boiler tubes were inspected during a scheduled outage after 9 months of service, the NanoSteel SHS TWAS coating did not show any signs of erosion or corrosion damage while both LMC Armacor™ coatings showed erosion damage requiring repair.
Severe erosion on boiler tubes
Waste coal fuel fired in a CFB combustion unit causes severe erosive wear on boiler tubes
Erosion Damages Competing Coating
LMC Armacor™ coated boiler tubes suffers erosion damage
NanoSteel Coating Reduces Material Loss
NanoSteel coated boiler tubes show almost no surface material loss from erosion or corrosion