North American Dismantling Corp (NADC) deployed the largest machine in its equipment fleet, an 89 tonne Volvo EC700CHR with a 32 m (105 ft) reach mounting a LaBounty MSD 1500 shear, during the challenging demolition it carried out at P H Glatfelter Company’s York, Pennsylvania, paper making facility. NADC was tasked with the removal of two chemical boiler buildings and an electrostatic precipitator to clear space for two new natural gas boilers.
NADC first removed two 1950s vintage chemical recovery boilers, one 40 m (130 ft) high and the second 30 m (100 ft) high, to lighten the overall weight of the superstructures. This was followed by dismantling stacks, combustion chambers, tube bundles and then the outer steel walls. This approach allowed NADC to maintain total control of the structure during demolition without impacting on normal operations. The job took six weeks and saw 2,500 tons of steel, concrete and scrap material removed – 94% of which was recyclable.
The biggest challenge was the limited space NADC had to work within. The boiler buildings were boxed between two operational control rooms – with a narrow 2.1 m (7 ft) passageway between – and live pipes carrying boiling liquefied paper pulp and steam. “We had to take every precaution to not puncture any of the piping or buildings with falling debris,” said NADC site superintendent Greg Goscenski.
He continued: “A power plant is a unique beast in terms of what is required to bring it down safely. NADC is a total demolition contractor, which means we demolish the buildings and get rid of the waste through site remediation, including salvaging equipment and selling scrap. Environmental issues are the main concern when decommissioning a power plant or industrial boiler system, especially in older plants. Larger power houses are usually situated along rivers or in downtown areas with surrounding utilities and higher potential water contamination issues.”
Working alongside the EC700 was a Volvo EC460B excavator with 9,500 hours clocked that was used for material processing, along with a Volvo EC380EL excavator equipped with a LaBounty grapple. On this job, Greg estimated a 10-15% saving in fuel consumption with this trio of machines.