Vale Inco’s Copper Cliff operations in Sudbury, Ontario consisting of six mines, a mill, a smelter and a refinery, are among the largest in the world. Bulk nickel and copper concentrate is obtained from the underground mines and treated by smelting the material with silica flux and technical oxygen in flash furnaces.
After removing the slag from the smelting mixture, the sulphide matte from the flash furnaces is tapped into ladles and transported to the converters where it is further oxidized for iron and sulphur removal. The slag from the converting stage is then returned to the flash furnaces for metal recovery and the finished Bessemer Matte from the converters is poured into casting ladles to be transported from the Converter Aisle to the casting building for further processing.
Looking to increase the daily production output, management at the Copper Cliff Smelter wished to determine the best possible configuration for all of the elements within the Converter Aisle. This information was crucial to the operations team, as processing even one additional converter cycle per week would result in the company realizing benefits in the order of tens of millions of dollars.
To help them achieve this goal, Vale Inco contracted Visual8 to develop a simulation based scheduling tool to investigate and evaluate different operating practices for running the Converter Aisle and ultimately determine the most effective operating strategy at high production rates.
A detailed production model was built to accurately replicate the flow of material through the Converter Aisle.
The processing equipment modeled includes 6 Converters, 2 Furnaces and a generalization of the Cu Washout Converter as well as the utilization of materials handling equipment including gantry cranes, transfer cars and the slag train locomotives.
The operations of resources and equipment within the smelter are all governed by user-defined parameters such as:
- Shift patterns,
- Converter recipes,
- Processing rates and
- Storage capacities.
Users are able to enter or manipulate this information directly in the model through a series of customized input spreadsheets and dialog boxes, which includes:
- Converter and crane operating parameters,
- API restrictions,
- Converter recipe specifications, and
- Various process event times.
Through the application of the detailed production model, the team could quickly evaluate the effect that different operating parameters and rules had on production through a series of custom reports and graphs. Users are able to access a variety of summary and detailed reports for each of the main equipment types, as well as an event log and a Gantt chart showing the simulated schedule.
The production model enabled the Operations Team to accurately predict output under a variety of different scenarios and is now used to quickly identify feasible operating strategies that achieve higher levels of production from the Converter Aisle with minimal disruption to the process. Through this, the team at Vale Inco is able to determine the most effective strategy for operating the aisle under any given scenario.
As an added bonus, the simulator has undergone a series of extensions so that it is also now used as a management tool for long-term planning.