After the successful supply and installation in 2011 of a lignite- capable plant to New Zealand’s RCR Energy Systems, RCR has now requested Tenova Takraf Africa, formerly Bateman South Africa, to extend the cross Redler conveyor to cater for a second boiler installation. In essence, the system draws coal from an in-ground holding bunker at a constant rate of 68tph (tonnes per hour) and feeds it to overhead boiler day hoppers.
TENOVA Takraf Africa’s Andrew Wager describes the system as consisting of a reclaim Redler chain conveyor, drawing a pre-determined volumetric load from a holding bunker and transferring it to a belt conveyor, which lifts the coal and inclines it 24m up a 21° incline. “From the belt conveyor it transfers into a cross Redler conveyor, which distributes the coal evenly in the bunker above the boiler, via three pneumatic slides on each of two hoppers and a final outlet,” he says.
He adds that because lignite is a ‘sticky’, relatively poor grade of coal, which is not free flowing, special design considerations had to be taken into account in the calculations and ultimate design.
RCR project engineer, Craig Weston, explains that the second boiler installation is an independent structure to the first, and in light of the recent catastrophic earthquakes in New Zealand, and with the project being near the epicentre of the first earthquake, more emphasis has been put on personnel and equipment protection.
Wager says that the brief from RCR was to cater for a combined movement of 120mm from one bunker to the other in the event of an earthquake. “After due consideration, we opted for a slip joint design in the casing and a spring assisted tension
end,” Wager says. Weston says that the ingenuity and excellent service they
have received from Tenova Takraf has encouraged RCR to continually do business with them. “They are excellent engineers and go the extra mile to provide equally excellent service,” he concluded.
This is the third order received by Tenova Takraf Africa from RCR Energy Systems in New Zealand for fuel handling systems over the last five years.
RCR Energy provides comprehensive turnkey Engineer, Procure and Construct solutions for utility, power and industrial energy projects, as well as overhaul and refurbishment of plants utilizing renewable energy, biomass, coal, gas and liquid fuels.
RCR’s service business is one of the largest fully accredited service and packaged boiler company in Australasia. With an extensive workshop and service network in key utility and industrial centres throughout Australia and New Zealand, RCR provides 24/7 emergency and service support to the local market.
Tenova TAKRAF is a major supplier of a complete range of systems for the mining and bulk handling sector and Tenova Bateman Technologies provides solutions covering; leaching, solvent extraction and electro-winning, beneficiation, purification, sulphuric and phosphoric acid plants.
Tenova is a worldwide supplier of advanced technologies, products and engineering services for the iron and steel and mining industries providing innovative, integrated solutions for complete process areas.
Tenova's network companies operate in 26 countries on five continents with more than 4,900 people.