IGS has completed a large number of successful projects with CFB boilers including applying HVTS to help eliminate forced outages and tube leaks, reduce maintenance costs and increase the runtimes and skip outages. IGS also uses SMARTGard® to achieve boiler maintenance goals and reduce repairs.
The following projects delivered significant benefits to the facility.
This coal-burning boiler was commissioned in 1998 with an 11,450 sqft (1064 sq.m.) heating surface and 1.2 million pounds per hour (544 t/h) steaming cap. IGS first applied HVTS in 2020 and monitored the condition of the boiler over two years.
This Pulp Mill in South Eastern United States operates a CFB boiler unit built in 1989. The boiler was recently upgraded from the viewpoint of operating mass flow rate to the 450,000 lbs/hr.
The fuel type for this particular unit is a combination of biomass sludge, some tire derivatives as well as some plastics. This type of fuel has led to the issues at hand – erosion causing tube leaks and numerous forced outages.
As a result, the Mill had a number of goals that IGS helped them to achieve.
This CFB boiler built in the mid-1990s is designed to burn anthracite coal, hazardous waste coal piles located throughout Pennsylvania. The plant observed severe erosion and metal wastage on the boiler tube due to how these combustors operate.
Over the last 25 years, the plant owner utilized weld overlay to protect boiler tubes against erosion. They have been using both carbon steel weld overlay and stainless steel overlay.
The application of HVTS helped both facilities achieve their key objectives:
After discovering metal wastage in 2014 and having to replace a panel section in 2016, engineers decided to protect new panels with thermal spray cladding.
Integrated Global Services (IGS) proposed SMARTGard®, a high velocity thermal spray (HVTS) alloy cladding solution, which was applied within 3 days, saving time and associated costs.
Inspections have confirmed IGS cladding to be intact after years in service.
This US City Hybrid Energy Center operates two 300-MW CFB boilers that burn a combination of coal mixed with up to 20% biomass.
The cladding along the water walls, as with any CFB, requires regular maintenance to rebuild the cladding thickness loss caused by the aggressive nature of ash erosion in these types of boilers. In high corrosion locations in the combustor, the coating can be utilized to mitigate tube thickness loss from this mechanism because of superior metallic properties that prevent further wastage.
IGS was invited to remedy the problem areas following technology discussions and a mid-year inspection where the extent of the problems were identified.
In this case study we are interviewing Joel Taylor, Boiler Engineering and Maintenance Specialist. Joel has ensured reliable operation of 7 Circulating Fluidized Bed Boilers between 4 Plants across his 15 Years of CFB Experience. Joel’s recent experience comes from 2X Foster Wheeler CFB Boilers that were burning Lignite Coal. Interviewing Joel is Ed Griffith, IGS CFB Boiler (SMARTGard®) Thermal Spray Expert, Integrated Global Services.
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
This Power Plant provides steam to nearby industrial facilities using sustainable biomass (such as SBP, GGL, FSC, and PEFC) and industrial by-products (such as bio-propane) to generate power and heat.
HVTS cladding can upgrade corrosion/erosion resistance of metallic substrate without impacting integrity even on a difficult-to-weld material, thus avoiding challenging tubes replacement.
IGS’ material engineers, project managers and technical managers, in close cooperation with the biomass plant
manager, have reviewed extreme corrosion/erosion findings and wear along the existing cladding to evaluate specifics of the evidenced wastage, fuel composition, and operational aspects.
As a result, IGS has introduced a cladding system customized to the process to mitigate the wastage and extend the life of the protection system. To maximize budget utilization during past outages, IGS has installed thinner specification cladding in 2015, limiting life expectancy but maximizing the coverage of critical threats to reliability during that operation campaign until 2017 outage.