The maintenance and management of the water treatment plant at Medupi Power Station is vitally important for the operation of the plant, as it processes harmful water produced during power generation, thereby ensuring that it is reusable.
Medupi Power Station is a greenfield coal-fired power plant near Lephalale, Limpopo. It is the fourth largest coal plant in the southern hemisphere and the largest dry-cooled power plant in the world. Leading rope access specialists Skyriders was tasked with carrying out maintenance work on the six water treatment units at the power station.
The water treatment plant is responsible for processing all of the processed water from Medupi Power Station. This includes all of the run-off water and the process water from the plant, which is then treated and subsequently pumped back into the system.
Skyriders marketing manager Mike Zinn reveals that the company was originally approached and tasked with maintenance on only half of the building, but was later commissioned to complete maintenance on the entire water treatment building.
“After two days of working on half of the water treatment building, we were on schedule and everything was going well. When the management at Medupi saw this they approached Skyriders about carrying out maintenance on the remainder of the building too,” he explains.
The concrete columns of the water treatment plant are approximately 6 m high, however, Zinn points out that the use of scaffolding for the maintenance work would have been a difficult and timely task. “By using rope access, the maintenance team was able to get up to the top of the columns and carry out the necessary work quickly and easily.”
The water treatment building is comprised of columns of concrete with a steel roofing structure on top of them. There are bolts attached to the column, below the roof, which can be adjusted to get the correct space between the columns and the roof structure. Once the columns and the roof are perfectly aligned, the space between the top of the columns and the truss brackets is filled with grout.
Zinn observes: “The Skyriders team had to get up to the top of the columns and prepare the concrete surface. After the concrete is prepared, shuttering is placed around the column and filled with the grout. Shuttering is a wooden box type structure that is open at the top and the bottom. Once the grout has dried, the shuttering is removed and the grout is smoothed.”
During this process, inspections had to be carried out by Medupi management. Zinn notes that it was difficult for the inspectors to get to the various inspection points. To overcome this challenge, the Skyriders team took photographs of the inspection points, which were examined by inspectors. Once the inspection points were deemed acceptable, the grout was poured, the shuttering removed and the grout smoothed. Photographs were then taken of the finished work to inspect the quality.
According to Zinn, there was a five man team working on the project. “There was a level 3 rope access supervisor who was in charge of the work team. All of the team members had basic concrete treatment training. The project went well, and we are optimistic about working on future projects at Medupi Power Station,” he concludes.