INNOVATIONS: PRESENT&FUTURE
Cracking the Code of Biomass Corrosion with HVTS Marina Silva IGS Integrated Global Services, Inc., Richmond – United States
marina.silva@integratedglobal.com
B
iomass energy is a hot topic in our current climate. While some operators build new biomass-ȴred boilers, others retroȴt old
coal-ȴred boilers to burn biomass. Alcali- and sulȴde-induced corrosion,
however, has become a problem for many boilers. Integrated Global Services (IGS) have developed and ȴeld-tested a novel HVTS metal alloy cladding to cope with corrosion in biomass boilers. Among the adopters of this groundbreaking technology is E.ON in Sweden (Fig. 1), who are now beneȴtting from lower operational expenses. IGS’s European operational team performed a High Velocity Thermal Spray (HVTS) application at E.ON Värme Sverige AB Åbyverket, Örebro, Sweden, on a steam boiler in 2017. ÅP5 is a 170 MW biomass-ȴred CFB boiler built in 1988 by Götaverken-Generator (currently Valmet Technologies Inc.) The steam conditions are 150 bar/540°C. Åbyverket wanted to upgrade the previously installed erosion protection in preparation to the fuel change during the boiler revamp. 20 m height of waterwalls were being changed on all 4 walls.
© IGS
Figure 1 - E.ON Värme Sverige AB Åbyverket, Örebro, Sweden.
Current Fuel mix: Stemwood
10%
Peat
20%
Creosote
30%
Saw dust
20%
coatings, Cyril Narjoz, said: “Some boiler operators believe that weld
Branches, peaks
5%
Dry wood chips
15%
overlay is the only solution to protect boiler walls from biomass-induced
Mix B5
Cl 0,3g/kg
Dust chem
SO3 7,5-41,6%
Flying ash
Cl 0,3%
S 1,3g/kg
Cl 0-5%
S 1,6%
Si 19%
its performance in several independent tests and practical applications.
K2O 11-21% Ca 12,5%
corrosion safely. It was true many years ago, but now HVTS has proven
pH 12,5
With its on-site application being much faster and easier than weld overlay, HVTS has become a favourable alternative for corrosion protection”.
Biomass fuel sources
HVTS application for E.ON
Biomass fuel can be derived from various sources, including virgin
For E.ON Värme Sverige AB, IGS applied 993,5 m2 (20 m band) of HVTS
wood, plants or animal residues, as well as recycled materials, such as
during a 3-week period, working 24/7 with eight spray units. Director
demolition wood. Depending on the type of biomass, the combustion
of IGS European Operations, Petr Sovadina, commented: “Our team is
can generate more or less corrosion and erosion. The type of boiler is
well-trained and experienced, however, this was our ȴrst large project
also an important factor: ȵuidized bed boilers will optimize combustion
in Scandinavia. We found E.ON engineers to be extremely sharp
but will also generate erosion. Various factors inȵuence the choice of
and skilled, this helped us avoid many obstacles during the project
erosion/corrosion protection.
execution. We understand that operators need to squeeze critical path of boiler operations, and that is the reason why we mobilized an
Innovation in corrosion protection
8-gun team to spray 995 square meters of waterwalls in just 21 days.
IGS Subject-Matter Expert on Waste to Energy and Biomass Boiler
We are proud of our quality and provide a warranty for our work.” A
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N.32 - 2019 DECEMBER - ipcm® Protective Coatings