Ball Mill Exchanged at Australian Alumina Refinery

MAMMOET’S BESPOKE ENGINEERED SOLUTION ENABLES UNINTERRUPTED MAINTENANCE AT ONE OF AUSTRALIA’S LARGES ALUMINA REFINERIES.

One of the largest alumina refineries in Australia needed to replace an aging ball mill critical to their operation. The mill was located in the center of the plant, making access challenging due to narrow clearances and thus the replacement operation required comprehensive engineering. As a result, Xtreme Engineering, a heavy fabrication company, partnered with Mammoet to provide a solution for the exchange and replacement of the old and new mill.

Recognizing the complexity of the task, the importance of the refinery’s continuous operations and team safety, Mammoet utilized its engineering expertise and advanced technological capabilities to develop a bespoke solution aimed to facilitate a seamless exchange of the mill, all while minimizing disruptions within the live plant.

By employing its proprietary Move3D engineering software in combination with traditional 2D drawings, Mammoet engineers meticulously planned every aspect of the operation, taking into account the mill’s challenging location with tight clearances and limited accessibility.

Given the spatial limitations within the work areas, the use of hydraulic cranes or gantries was not viable. Recognizing this challenge, Mammoet developed an innovative solution that entailed the use of a ‘jack and pack’ system. With no as-built drawings available, Mammoet utilized a point cloud scan, provided by the customer, to generate an accurate representation of the plant in its current state within Move3D, facilitating a comprehensive visualization of the entire operation.

The jack and pack system involved employing self-propelled modular trailers (SPMTs) with strategically positioned cassette towers. Four internal towers placed on the SPMTs, and four external towers positioned on the ground adjacent to the trailers. By adding or removing jacking cassettes, the team could control the height of the mill by redistributing the load between the internal and external towers via the SPMT’s hydraulic suspension.

The process commenced with the removal of the aging mill. The internal cassette towers were pre-assembled to a specific height on the SPMT, which was then maneuvered underneath the mill and then raising it until the mill was clear of its foundation. Leveraging the exceptional steering capabilities of the SPMT, the mill was then transported off site, skillfully navigating congested areas. The process was then reversed to install the new ball mill.

Liam Bradburn, Mammoet’s Engineering Manager, emphasized the role of Mammoet’s Move3D software in enabling the safe and successful replacement of the mill. “The customized jack and pack system allowed us to maneuver the mill in and out of the live plant with minimal disruption to the existing infrastructure and ongoing production.” he added.