BlueScope Steel Limited, a steel mill located in Australia, operates one blast furnace and supplies steel products mainly to the Australian market. For iron ore and additives for steel production, the company operates a primary stockyard for ship unloading and a secondary stockyard for material blending and sorting. These compact, high-utilisation stockyards are equipped with three ship unloaders and two bucket-wheel stacker/reclaimers, which were commissioned in the 1970s and converted in 2014 from relay control to programmable logic control (PLC).
The multifaceted challenge
In addition to high operational costs and little available space and throughput in a compact stockyard, BlueScope also faced on-site challenges that arose in the course of the project. For example, a supply road had to be factored into the automated system design to ensure that one of the stacker/reclaimers did not intrude upon road traffic. BlueScope wanted a stockyard automation solution to cut operational costs, maximise stockyard area utilisation and boost reclaiming throughput. However, the variety of operating methods and the multiplicity of materials has traditionally made it difficult to rely on anything else but skilled operators and to some extent semi-automatic or remote systems.
A logical solution
BlueScope chose FLSmidth’s BulkExpert™ because it is a unique, patented solution that focuses on unmanned and custom site optimised operation of any combination of dry bulk equipment. BulkExpert is the only system that uses a 3D laser scanning system combined with a dedicated RTK-GPS array to produce real-time, full-terrain information of the stockyard. The BulkExpert system reduces flow rate variances by more than 40% and has nearly doubled reclaiming throughput for BlueScope, from 10-12,000 to 19,000 tpd. The BulkExpert solution also provided BlueScope a collision avoidance safety component. Every moving piece of equipment, including three ship-unloaders, is fitted with a GPS receiver, so the system can automatically alert the central operator if machines are within the vicinity of outer-limit operations, and perform a machine shutdown if there is danger of collision.Rapid delivery was part of the package and working together with BlueScope, FLSmidth completed installation within two months; the system was operational in October 2014 and performance tests were conducted successfully in November. Much of the existing hardware was revitalised, many of which were more than 30 years old. Space utilisation and operational efficiency have been improved by the system’s simulation capability, which significantly improved planning, allowing management to plan days ahead and decide exactly how incoming material will be stacked and reclaimed. Safety has also been increased because the unmanned BulkExpert system allows stockyard machinery to operate consistently close to operational limits without exceeding them. The system has also significantly reduced maintenance costs by reducing machine movements. All of which is expected to add up to a full ROI within two years.