SCHENCK has exported a deck screen with a mass of nearly 60t to Canada. The screen is powered by six Schenck DF601V exciters and measures 4m x 9.6m.
It replaces a smaller screen in an oil sands operation in northern Canada. The screen will be installed on the client’s existing isolation frame and will use the existing dual-output gearbox and motor to drive the two rows of exciters. The screen will receive up to 10,000t/h of solid feed, which includes large frozen lumps up to 1m in size.
The oil/sand material contains up to 15% bitumen and its handling properties vary depending on bitumen content, geological properties and seasonal conditions. The properties range from free-flowing to a cohesive mat that is difficult to break up. The raw feed is mixed with up to 2,000t/h of hot water for processing.
The deck is a thick heavy-duty screen surface with a combination of tungsten carbide and chromium carbide coatings, overlayed on the heavy steel backing. The screen operates outdoors, exposed to the extremely harsh environment, with ambient temperatures of between -45°C and 35°C.
The material being screened is a 70°C corrosive slurry of hot water and very abrasive oil sand. Special materials and construction methods were used to cope with the extremely cold environment and the unusual process requirements of high-temperature corrosive liquid. The screen is critical to the process of supplying raw material to an oil refinery on a 24-hour basis, with minimum stoppages for maintenance and deck changes.
The screen was constructed so that maintenance staff will have minimum exposure to the severe environments. Due to the mass of the screen, it had to be assembled outdoors to allow large mobile cranes to lift the machine onto the test frame and the truck that took it to Fremantle for export.