By: Mariaan Webb
16th December 2005
Kumba’s growth plans, comprising the R2,96-billion Sishen Expansion Project (SEP) and expansion plans at its Sishen South mine, will increase iron-ore exports through Saldanha from 23,5-million tons a year to 35-million tons a year by 2009. Iron-ore miner and exporter in the Northern Cape, Assmang, will also increase exports of iron-ore from six-million tons a year to about ten-million tons a year by establishing a new mine, at an estimated cost of R1,5-billion to R2-billion on the farms Bruce, King and Mokaning (BKM mine), adjacent to Kumba’s Sishen mine. This will bring the current rail expansion plan up to 45-million tons. Earlier this year, Trans- net and Kumba jointly announced that the con-tract supports South Africa’s participation in the growing world de-mand for iron-ore and contributes to the domestic economy with investments and employment associated with mine expansions and new railway rolling stock and infrastructure. The first phase of the contract between Trans- net and Kumba will provide rail and port infra- structure to accommodate the increased produc-tion from the iron-ore-mines in the Northern Cape.
Orex railway line The rail portion of the Sishen-Saldanha iron-ore capacity-expansion project, a joint effort by Kumba and Assmang, is to increase tonnages mined, as well as tonnages railed by operator Spoornet, to improve its export capacity from the Northern Cape to the Saldanha harbour from the current 29-million tons to 39-million tons a year. Spoornet’s plans for its Sishen-Saldanha line include expanding shunting yards; increasing the length of crossing facilities; introducing new technology and new rolling stock; and phasing out diesel locomotives, which are expensive to operate owing to high fuel costs. The current electric locomotives are being upgraded. With Eskom agreeing to shorten the current interval between substations, Spoornet will be able to use more locomotives per train, ensuring the trains can be made much longer (currently more than two kilometres), thereby increasing pro- ductivity. There is also increased effort to improve turn-around times of trains, by increasing the loading rate at the mines to 5 400 t/h.
Bulk terminal Saldanha Next year will mark the 30th year since the first iron-ore from the Sishen mine arrived in Saldanha Bay, bound for export to Europe. The Bulk-Terminal Saldanha cur-rently handles 29-million tons of iron-ore a year, though it was only designed for an 18-million-ton capacity.
Kumba iron-ore division GM Matie von Wielligh tells Engineering News that the 30-year old equipment needed refurbishment and some of it needed to be replaced. The first phase of the port expansion includes the installation of a second tippler, a third stacker reclaimer, the replacement of the two existing stacker reclaimers, a second parallel conveyor system, the upgrading of the existing conveyor system and the replacement of the two existing ship loaders.
Refurbishment and Expansion Project, Bulk-Terminal Saldanha con- struction manager Gert Olivier reports that two new ship loaders and two of the three stacker reclaimers are already fully operational. “The second tippler, the third stacker reclaimer and the second conveyor system are in commissioning phase and should be fully operational by the end of this month,” he says.
The refurbishing of the existing tippler and conveyor system is scheduled to start during April next year with completion by October 2006.
Olivier reports that once the new equipment is fully operational, and refurbishment of the existing tippler and conveyor system is completed, the Bulk Terminal would be able to handle 41-million tons of iron-ore a year by 2008.
This R920-million refurbishing and expansion project is currently the largest capital project undertaken by South African Port Operations and is one of the ten largest projects currently being executed in South Africa.
He says that the construction site labour force peaked at 552 employees during July.
Area managers in the civil-, mechanical- and electrical-engineering disciplines managed the execution of the refurbishment and expansion project.
Civil engineering Southern Oceaneering was awarded the contract to increase the existing stacking capacity in the stockpile area by the revetment and reclamation for a third new stacker reclaimer. The contract for a diaphragm wall, reinstate-ment of ground mass, tippler vault and associated infrastructure was won by Protekon Construction, which subcontracted the diaphragm wall and reinstatement of the ground mass to subcontractor Franki Africa. The work on the jet-grout plug below the vault and tunnel floor was subcontracted to Rodlo. Oliver reports that the jet-grout plug and dia-phragm walls form a water-tight chamber about 120 m long and 10 m by 6 m wide, varying in depth from 5 m to 14 m, with the deepest area about 6 m below sea level. He says that the iron-ore bunker, apron-feeder chamber and conveyor tunnel were constructed within this chamber and adds that the dia-phragm walls serve a dual purpose as they are also the walls and foundations of the tippler superstructure.
“Construction of the tippler vault has been an engineering headache as intermitted flooding of the chamber during excavation was experienced, causing a delay in construction of about eight months,” Olivier says. About 6 500 m3 of concrete and 760 tons of reinforcing steel were used to construct the diaphragm walls, tippler superstructure, positioner area and conveyor tunnel. The superstructure sup-ports the tippler drum, positioner and associated mechanical infra-structure. Scott Steel has built a 78 m * 20 m * 11-m-high structural steel building over the tippler and positioner structures. Two contractors carried out the contract for the realignment of haul road and building of a new rail siding. Hughmic Construction constructed the realignment of the haul road and Protekon Perway constructed the new rail siding for the second tippler.
Protekon Construction won a contract for installing track slabs for three new stacker reclaimers. The track slabs consist of two continuous concrete slabs paral-lel to each other, 2,5 m wide * 0,25 m thick * 600 m long, for each stacker reclaimer. By the time of going to print, 2 700 m of the 3 600-m track slabs had been completed. The same contractor has also constructed all the conveyor bases and footings. Approximately 4 000 m of conveyor system support bases and plinths of various shapes and sizes had been constructed alongside existing operational conveyors.
Olivier says that dust suppression has been an important environmental requirement and, with the increase in iron-ore export volumes, the dust suppression facilities also needed to be upgraded.
Protekon Construction installed a 1 200 m3 storage tank, a pump station and some 5 300 m of sprinkler piping. Standpipes will provide sprinkler water at a rate of about 600 m3/h at ten bar pressure to wet ore stockpiles for dust control.
Krupp Materials Handling installed two new travelling and slewing ship loaders on the quay-side, and Olivier reports that these have been fully operational for more than a year now. Two of the three new stacker reclaimers have been handed over to the client and are fully oper- ational. Meanwhile, contractor Metso Miner als is still commissioning the third stacker reclaimer, which will be opera-tional by the end of the year. The same contractor has also instal-led a second tippler. The tandem wagon rotary tippler will be able to offload two 100-ton rail wagons at a time. The average operating capacity of the tippler as well as that of the stacker reclaimers, ship loaders and conveyor system is 8 000 t/h.
Olivier says that the train currently operates with 216 trucks from Sishen and that it gets split into two 108-truck trains at Salcor. From there, it is then shunted to the Bulk Terminal and offloaded. However, he reports that discussions to run trains with 342 trucks in the future are proceeding. “This will mean that the new tippler and the existing tippler, after being refurbished, will be able to handle 114-truck trains as opposed to the existing 108-truck trains.
“The infrastructure also makes provision for a dual-tipping operation where both tipplers offload trains at the same time,” Olivier notes. Senet won the contract to install the second conveyor system, which will be operational by the end of the year. The two old ship loaders and the two old stacker reclaimers have been demolished and removed from site. The asset-removal contract was placed with Fine Trading as principal contractor, and LVP Projects and F&G Marketing as subcontractors.
Olivier reports that the total electrical system will be replaced with modern equipment. The new switchgear is being commissioned as the new equipment comes on line.
The new control system is based on the latest state-of-the-art PLC, Scada and network tech-nology. The system uses accurate position-feedback equipment (absolute-position encoders), which makes fully-automatic operation possible.
The central-control equipment includes a mod-ern material-tracking system and an archive which enable the archiving of every event, alarm and fault condition for each and every signal on the entire plant. The archive has the capacity to store the detail of all the conditions and events on the total plant for several years.
The contractors involved in the electrical side of the project are: Automation Concepts Electrics and Control (electrics and control, conveyors); Dynamic Instruments Electrics and Control (stacker reclaimers); Siemens Ltd Central Scada system (ship loaders) and Intech Instruments (material tracking).
South African Port Operations’ Dan Reddy notes that this project marks the installation of the first one-gig Industrial Ethernet communication in South Africa.
Project in perspective
Reddy reports that the refurbishment and expan-sion project at the Bulk-Terminal Saldanha is 24 months behind the original schedule.
“This is primarily driven by the catastrophic leakage in the below-ground level-tippler vault area and also by poor performance by one of the main mechanical contractors. “Overall, it has been a difficult project, with major hurdles interfacing ongoing operations with commissioning of a new plant,” Reddy says. However, he points out that a South African Port Operations-appointed civil consulting company, based in Durban, used advanced geotechnical monitoring and quality assurance techniques for the rectification of the tippler leakage.
“We believe that it is a first for similar types of construction work,” Reddy says, adding that team spirit, tenacity and a ‘never-give-up’ attitude of the total project team, including the contractors, contributes to the success of the project. Von Wielligh reports that the rail tonnages carried are currently higher than the tonnages exported by the port and this is owing to Saldanha Steel’s buying 1,8-million tons a year.
Reddy adds that the average throughputs have increased from 4 500 t/h to 8 000 t/h, a 77% improvement, peaking at 10 000 t/h subject to free-digging rates, ore type and parcel size.
By the end of next year, the port will have installed capacity of 41-million tons a year on the rail side and 39-million tons on the export side.
“South African Port Operations can now increase availability and reliability, which will hopefully then translate into further efficiency gains on the channel,” Reddy says. Von Wielligh adds that Kumba’s Sishen expansion project is tightly aligned with this schedule. He also notes that the Saldanha port is headed for record export figures of iron-ore this year. “We are planning to export a million tons more than last year, which will take export to around 22-million tons this year,” he highlights. He highlights the management of the project as one of the main challenges.
“This is not only attributed to the fact that Kumba managers assisted with the implementation of the project, but also owing to Kumba’s managing the port por-tion of the project. “We were both the customer and the service provider,” he says. The construction of the new infrastructure also had to take place while the port’s normal day-to-day operations carried on, which complicated the management of the project. The estimated total cost of the refurbishment and expansion project at Bulk Terminal Saldanha has increased by 3,3%.
“This is owing to the above slippages, but on a positive side, although 24 months late on original schedule, the port will be two years ahead of client requirements,” Reddy says. “Recognition must be given to the project teams, customers, clients and management for the support in reducing the impact of the slippages and technical problems encountered,” he says, highlighting the work of the Kumba Technology team.
“This project is only the beginning of an even bigger story,” Von Wielligh reveals, adding that Kumba will require further expansion in the future as it is increasing its capacity with SEP and its Sishen South mine. Assmang is also ex-panding its operations and is in the process of establishing the BKM mine.
“The environmental assessment has been com- missioned. Transnet, in cooperation with Kumba Resources and Assmang, is in the process of drawing up a master plan to more than double the current contract capacity,” he says, adding that nothing has been approved yet. Further expansion on the port, to handle a fore-cast 90-million tons a year by 2015, is planned. Phases two and three are expected to be com-pleted by 2012.
Edited by: Mariaan Webb