Outotec Ausmelt TSL Furnace Manufactured In China For Nyrstar Redevelopment Project
Nyrstar’s historic lead smelter located at Port Pirie in South Australia is currently undergoing a major modernization including the installation of an Outotec Ausmelt TSL furnace. As announced in June 2014 Outotec will provide a technology licence, engineering, proprietary equipment and advisory services for the redevelopment of Nyrstar Port Pirie into an advanced metals recovery and refining facility. Outotec’s equipment delivery includes supply of the furnace shell, baseplate, roof, outlet weir, offgas transition, taphole components, furnace support structure, lances and lance handling system.
Nyrstar's Port Pirie smelter has been in continuous operation since 1889, with many of the core production assets having been in service for up to 60 years. While considered the best practice at the time, these assets are no longer capable of meeting the increasingly stringent environmental and operational standards expected of a modern base metals facility. Outotec Ausmelt technology has been used to upgrade the facility to an advanced poly-metallic processing and recovery facility capable of processing a wide range of high value, high margin raw materials with improved environmental footprint and reduced airborne metal and dust emissions.
The redeveloped facility will produce the current range of metals including lead, zinc oxide, gold, silver, and copper. However, the application of Outotec's high temperature top submerged lance (TSL) bath smelting technology will allow a wider range of raw materials to be processed. The increased furnace flexibility will allow Nyrstar Port Pirie to process a wider range of high value and high margin concentrates and residues from Nyrstar's existing smelters.
Figure 1: Completed furnace shell and lifting beam
Successful fabrication of furnace
The Outotec Ausmelt TSL furnace shell and its associated parts were delivered to the smelter site in Port Pirie in September 2015. Lead time from placement of fabrication order to despatch from fabricator’s yard was eight months.
This equipment was fabricated in Jiangsu province, China in the same shipbuilding and fabrication facility that previously built many Outotec thickeners and flotation cells. Several factors contributed to the success of this order:
- Established good working relationship between Outotec’s local office in China and the fabricator.
- The fabrication facility is eminently suited to the working of heavy plate and handling of large items.
- Continuous presence of Outotec’s own Quality Control inspectors during the whole period of fabrication, resulting in rapid resolution of any problems and excellent finished quality.
- Fabricator’s location on the bank of Yangtze River made possible the direct loading to river barge which then travelled approx 12 hours downstream to the port of Shanghai where equipment was transferred to a chartered ocean ship.
- Nyrstar smelter’s location is adjacent to a suitable wharf in Port Pirie, thereby avoiding any significant land transportation.
This achievement clearly demonstrates Outotec’s capability to fabricate quality furnace equipment in a low cost country within the agreed project delivery schedule.
Outotec Ausmelt TSL Furnace features
The furnace shell (see Figure 1) is a single weldment including cooling water jackets with a total mass of almost 140 tonnes. It is approximately 15 metres in height and 9 metres in width and is predominantly constructed from shipbuilding steel due to easy availability with suitable strength and impact properties. Three lifting points are provided, including two trunnions near the upper end for erecting to vertical during installation.
The furnace support structure (see Figure 2) is a grillage of horizontal beams in two layers, assembled into a single unit with four lifting points provided for transport and installation. It has a total mass of approximately 75 tonnes with a length and width of around 8 metres.
Figure 2: Furnace support structure
The offgas offtake transition (see Figure 3) is a single weldment including water jackets and inspection doors. It has a total mass of approximately 34 tonnes and is designed to be supported independent from the furnace itself.
Figure 3: Offgas offtake transition
The furnace roof (see figures 4 and 5) is in two sections, removable for re-lining. Each section includes water jackets and removable port structures to accommodate the lance, feed stream, standby burner and bath sampling system. Each section is bolted to the furnace shell.
Figure 4: Furnace roof - lower section with ports for feed and standby burner
Figure 5: Furnace roof - upper section with lance port
The outlet weir (see figure 6) for hot products is a separate ‘box’ bolted to a flanged opening in the furnace shell.
Figure 6: Hot products outlet weir
Text: Paul Abbott, Director TSL Smelting, Outotec