Concentrate feed to the roaster, which is a key component of the sulphide processing circuit at Syama, is expected to begin in about five days.
The repair program was completed within the scheduled timeline, within the allocated budget and without any recordable safety incidents.
Syama’s roaster was taken offline in early October due to the detection of a crack in the main external shell.
Work completed safely
Managing director and CEO John Welborn is pleased the roaster repair was completed safely, on time and within budget and he congratulated the Resolute team.
“I am delighted and proud that we have successfully executed the repairs to the Syama sulphide roaster,” he said.
“The positive culture and attitude within our team, shared by our business partners, has delivered a speedy and successful solution.
“We are now reheating the roaster and expect to shortly return the sulphide circuit to full operational capacity.”
Syama roaster showing repair locations.
The repair schedule consisted of completely replating the crack on the main roaster body by cutting and welding new 10mm plate steel.
An additional crack in the primary cyclone and two minor cracks on the main roaster body were also replated during the repair program.
A 10mm steel plate exoskeleton, insulation and cladding was installed over the repaired section.
Peak workforce of 200
There were 127,344 man-hours expended on the roaster repair program with a peak workforce of 200 personnel from 22 countries.
The program required five cranes, 21 welding machines, seven items of heavy mobile plant, 64 procurement packages, 19 construction packages, 12 services packages, 25 tonnes of boiler plate, 45 tonnes of scaffold, 60 tonnes of refractory, 27 air cargo packages and two dedicated cargo aircraft.
The repair program included extensive refurbishment to the roaster and new installations.
Airfreight was used to transport much of the equipment for the repairs.
Other work carried out
During this program, a new secondary cone crusher was installed to the sulphide crusher circuit.
The company also undertook chute improvements, reline of sulphide primary mill, refurbishment of the sulphide grinding circuit and the flotation circuit, process flow improvements in the calcine regrind circuit, replacement of concentrate thickener rakes and carbon leach tank refurbishments.
Considering shutdown deferral
This work in addition to the roaster repairs has created an opportunity for Resolute to consider deferring the major biennial roaster shutdown previously scheduled for May 2020.
After the roaster is reheated the company will monitor operational performance to determine if the roaster shutdown can be deferred until January 2021.
Welborn said, “We remain committed to delivering on our ambitions at Syama by delivering stable long-life, low-cost production from the Syama Underground Mine.
“With significant ore stockpiles now available we are preparing for a highly productive period at Syama during 2020.”