Air Heater Air Outlet Fabric Expansion Joint on a Lignite Fired 600MW CFB Boiler

Problem

Often the primary air pushed through the heater baskets on the air heater air outlet is considered to be “clean”. In reality, there is fine particulate that clings to the baskets and as the primary air passes through it pushes the dust into the ducts downstream. The dust collects in the low spots and eventually packs in tight enough to rupture expansion joints.

The original OEM supplier failed to recognize the potential hazards for this application, and the joint became the cause of several un-planned outages.

Solution

Holz Rubber immediately recognized the problem and replaced the joint with a fabric expansion joint design that eliminated the collection of dust in the cavity. The plant has not experienced any further issues at this location.