Animal and Pet Care & Food Manufacturing Company Hot Well, Hot Water Tank Lining Project

We were contacted by a major pet and household care manufacturer located in the East of England regarding the possible refurbishment and lining of a hot well tank that supplied the factory with hot water. Hot well, hot water tank, lining service Hot well located above an industrial boiler The tank had the following major issues: The tank was leaking from several places The tank was approximately 8 years old, but was very severely corroded and very deep pitting or cratering The tank operated at a high temperature and water seeping from the tank was a potential safety hazard The tank was located in a small room approximately 3m above the boiler Because the boiler had to be working throughout the project, the temperature around the entrance to the tank was around 40oC. There were numerous hot pipes and steam in the vicinity of the manway entrance The tank was relatively small and had complex array of internal steelwork and pipes which would make working conditions within the tank challenging Due to the location & position of the hot well tank, close to the underside of the roof of the building, replacing the tank would be very expensive and time consuming The Engineering Department had welded an external plate to the underside of the tank in an attempt to stem the seepage of water and to strengthen the tank Hot well, hot water tank, extensive corrosion, craters & pitting.Hot well, hot water tank, extensive corrosion, craters & pitting Hot well, hot water tank, extensive corrosion, craters & pittingHot well, hot water tank, extensive corrosion, craters & pittingHot well, hot water tank, extensive corrosion, craters & pitting Extensive corrosion pitting & craters inside the hot well hot water tank Our Solution Abrasive grit blast the internal surfaces of the tank to SA2.5 Remove spent abrasive, dust and scale Apply a special high temperature tolerant epoxy tank lining system The tank lining system that was to be used, is a low odour solvent free glass flake reinforced system specifically designed for high temperature applications and for use in confined spaces. The lining resin is also potable water and food contact approved. Apply a primer coat of the high temperature resin Repair holes and craters in the tank using a special resin based surface repair system Apply high temperature main coat in multiple application layers to ensure complete coverage Test the applied lining for coating thickness and absent of holes in the new lining Hot well, hot water tank, corrosion craters & pitting exposed after grit blastingHot well, hot water tank, corrosion craters & pitting exposed after grit blasting Example of extensive corrosion pitting & craters exposed after grit blasting The Actual Job Protect the surrounding area from dust contamination with the assistance to the plant personnel The abrasive grit blasting took longer than expected due to the extensive scale, rust and other deposits on the walls and other surfaces of the tank and poor visibility After cleaning the tank, we primed all internal surfaces within the tank with the high temperature resistant epoxy primer We repaired 17 actual holes that went through the shell of the tank and numerous very deep craters that were close to perforation - these were repaired using our specifically developed tank repair material. The floor of the tank was reinforced with a screed coating Applied the main lining material to all internal surfaces in several applications The tank was rigorously tested throughout each process Although there was a delay during the surface preparation stage of the works, the lining application side of the work was completed on time as projected Detail of pipework in hot well tank before start of surface preparation and grit blastingDetail of pipework in hot well tank after lining completed Hot well tank before and after lining Hot well, hot water tank lining. Before lining work stated. View into tank from roofHot well, hot water tank lining work completed. View into tank from roof Hot well tank before and after lining treatment The Conclusion The tank was restored to production with a life expectancy of 10-15 years, subject to regular inspections and maintenance as required. From discussions with the engineer on site, the cost of lining the existing tank was considerable less than 10% the cost of replacing it.