Chlorine Corrosion in CFB Coal/Biomass Boilers

Inspection

During two years in service, the IGS’ SMARTGard® solution which uses high velocity thermal spray solution safely protected pressure parts. As a result, a two-year maintenance contract has been agreed, extended to a three-year contract in 2021.

PROBLEM

Straw was added to the fuel mix of two CFB boilers originally designed for coal firing (SKO Energo Power Station), leading to chlorine corrosion.

SOLUTION

Following a failed thermal spray application by a different vendor, IGS was contracted to apply HVTS cladding as a pilot project in 2017.

Timeline

2015 – Biomass (straw) added to the fuel mix.
2016 – Severe chlorine corrosion-erosion identified. Third-party thermal spray coating failed to stop corrosion.
2017 – IGS HVTS pilot project initiated. Application is a success, chlorine-induced corrosion-erosion is stopped.
2019 – Two-year maintenance contract is signed between IGS and Sko Energo to continue protecting CFB boilers from further corrosion.
2021 – Maintenance contract due to be extended for another three years.