The Enviro-Max 70 Hopper, built for Sun Metals in Townsville, was unique in that it was specially designed to facilitate the unloading of zinc concentrate for transport to their plant while also being capable of loading ships with zinc ferrite for export.

The project brought a number of challenges for the company: The hopper needed to eliminate dust emissions, the product itself was sensitive to compaction and did not flow well and an extremely tight delivery deadline was also required.

Awarded the project in January 2016, Page Macrae Engineering engaged the services of a specialist consultant to carry out flow testing on the zinc product and report on handling difficulties. The result of the findings determined that a radical new approach to the design was required. The design called for a larger than normal hopper opening to achieve flow and to transfer the product to the truck a unique batch loading process was required. The end result, filling of a 90-tonne triple trailer road train in under 10 minutes.

In order to meet local dust suppression regulations, the truck filling operation was enclosed and fitted with a dust extractor and self-cleaning filter system. This enabled the hopper to maintain negative air pressure inside the enclosure preventing dust from escaping as well as dust suppression at the grizzly.

The 220-tonne unit was completed in October 2017 and shipped to Townsville for commissioning.

The system was successfully tested and commissioned and is now fully operational.

2010 saw the introduction of a new era in discharge hopper and grab technology.

Page Macrae Engineering was tasked with providing a solution for POAGS (now known as QUBE) Darwin operation. The client needed to comply with strict environmental standards being introduced around dust emissions. As the port shared the harbour and waterways with recreational users, they needed to ensure they did not damage the resource.

We undertook a major research and development project to deliver on both the customers and environmental requirements. The result, a newly designed and built eco-hopper and grab solution designed to minimize dust emissions while maximizing productivity.

The hoppers provided the vital link between removing bulk cargo from the ship’s hold and discharging into the waiting trucks as swiftly as possible. Special discharge spouts automatically adjusted according to the height of the load in the waiting truck, containing dust in the hopper rather than losing it to the atmosphere.

Three newly designed diesel hydraulic bulk grabs were supplied as part of the package and incorporated the dust sealing and mobile remote-control technology.

In 2010, Page Macrae Engineering delivered four, 14 cubic metre bulk discharge diesel-hydraulic grabs to the enormous Koniambo nickel project in New Caledonia.

In 2010, Page Macrae Engineering delivered four, 14 cubic metre bulk discharge diesel-hydraulic grabs to the enormous Koniambo nickel project in New Caledonia. The project was a joint venture between the New Caledonian development agency and mineral company Xstrata Nickel. Xstrata will extract some 380 million tonnes of saprolite over the mine’s 50-year lifespan.

The remote coastal peninsula location, preservation of wetland, waterway and marine environments, were requirements of the mining company. Efficient use of energy, protection of natural resources, waste minimisation and biodiversity conservation were mandates for the project.

“The specifications for the project were very tight around our client’s expectations around noise and dust emissions from grab operation. We spent many hours designing and developing some new technology to incorporate into these grabs that is standard throughout the diesel-hydraulic range now,” said Port Equipment Manager, Bruce Ennis.

The Koniambo project also required equipment that did not compromise on productivity. The compact profile of the grabs and low drift profile suited the deep channel loading facility.

Downtime and maintenance minimisation were critical parameters. The grabs were fitted with diagnostic systems to ensure diagnosis was kept simple enabling faults to be fixed quickly. Building the power plant into the own sliding subframe module ensured the engine could be easily removed for servicing and testing. It also enabled a lower centre of gravity through the grab.

The Koniambo project marked a significant shift in grab design thinking and resulted in a major research and development project into productivity and environmental sensitivity.