Identify and evaluate coatings systems likely to survive severe conditions encountered in power plants.
Upgrade current high temperature test facility testing under a thermal gradient.
The project will use the recently built high temperature (HT) corrosion facility at TWI (CRP 18470). The test facility allows coatings and bulk materials to be tested in various high temperature corrosive environments. In the previous work at TWI it has been observed that the presence of interconnected porosity in thermal spray coatings, and the coating composition, can undermine their potential as protective layers against corrosion. In this project, multi-layered, composite (thermal spray coating & slurry sealant) structures will be deposited (in collaboration with AMP (CRP Ref 09-05-B)), tested in high temperature corrosive environment, and their performance will be analysed. Candidate coatings and processes for corrosion testing will be selected from the following:
Novel materials eg nano/amorphous-structured, pseudo-alloys and Ni-based super alloy derivatives.
Deposition by novel processes including high efficiency HVOF, cold spray, exothermic spray, suspension fed thermal spray and spray fuse.
Combination of coating processes eg combined slurry and thermal spray.
In power plants, the boiler tubes experience corrosive environments under a thermal gradient and it is more likely for the corrosion products to spall when the boiler tube is cooled. A modification of the current HT corrosion facility will allow coating systems to be tested under a thermal gradient.
Relevant Industry Sectors
Power, Oil, Gas and Chemicals
Technical and Economic Benefits
Improved understanding of high-temperature corrosion mechanisms.
Identification of functional coatings for high temperature applications.
Life extension of high value combustion facilities, reduced maintenance costs, improved reliability and improved safety.
Higher operating temperatures and thus increased overall energy efficiency for biomass, WtE and co-firing power plants.
Will enable increased utilisation of biomass and waste fuels in conventional combustion processes. The potential UK conventional mass burn waste incineration market is anticipated to be 1.5B p.a. with an additional 120 plants required over the next 20 years. The use of biomass combustion in dedicated biomass and co-firing applications is also expected to increase significantly to help meet the UK target of achieving 20% of energy generation from renewable sources by 2020. Biomass currently amounts to ~4% of electricity generation but is expected to rise to ~12% by 2020.
Industrial Member Report
Access the Industrial Member Report resulting from this programme: Corrosion Testing of HVOF Coatings in High Temperature Environments for Biomass Applications