Brahma Group conducted a six-month execution and safety analysis to prepare for the rebuild of the flash-converting furnace at the Rio Tinto Kennecott Utah Copper facility near Salt Lake City. While planning, the contractor says it paid particular attention to the design, removal and reinstallation of its copper water-cooling elements.
Brahma Group says the elements protect the furnace lining and structure from extreme heat. They also maintain the temperature ranges required for the furnace to operate properly. But these elements are extremely heavy and much of their weight is at the top, making them unstable and easy to topple. If not handled properly, they could fall and crush someone or damage expensive equipment.
To make the job more difficult, the bottom of the furnace is concave—exacerbating the common jobsite hazard of slips, trips and falls. Full-face respirators, required during removal of brick and furnace elements, often magnify potential risks because they restrict visibility.
The use of heavy equipment inside the furnace would have posed additional risks to the crew's safety and was not considered a viable option. Instead, Brahma designed a system that allowed crews to move elements inside the confined furnace space without heavy equipment. Specialized air-bearing casters were placed under pallets; the acute air pressure created an air cushion that "floated" the loads with nearly frictionless movement in any direction.
However, the furnace floor had to be flat and level for the casters to work. After the brick was removed from the furnace's permanent hearth, a temporary floor was installed over the existing concave floor.
A structural-steel frame was covered with grating for stability, and a steel-sheeted floor was installed on top of the grating to provide a smooth surface for the casters to operate.
The submitter says this safe-and-effective customized system can be replicated for similar rebuilds with minor modifications based on each furnace's size, shape and design.
Excellence in Safety Winner—Intermountain Area
Best Intermountain Energy/Industrial Project
Salt Lake City
Owner Rio Tinto, Kennecott Utah Copper, Salt Lake City
General Contractor Brahma Group, Inc., Salt Lake City