Greg Vercellotti of Dariel Solutions, a software development and business enterprise systems integration group, says that over the past five years mining companies have been focusing on improving their metal accounting systems
Metal accounting covers the metal content of a mining company’s output from the processing plant onward. It can be defined as a complete account of what has happened to the metals that have been put into a process. Though metal accounting is not new, recently companies have been installing systems to upgrade their insight as to what metal they have in their systems along this chain. South Africa and Australia have taken the lead in the evolution of metal accounting systems, whose effective implementation involves breaking down the complex processes into small enough portions so that they can be measured and managed.
“This will upgrade the ability of mining companies to forecast their output, and is a move away from metal accounting in isolation on a monthly basis,” Vercellotti says. “Metal accounting is now being looked at to provide a lot of information to other business processes, and how it can add value to the organisation, with information on aspects of the business such as yields, cost of processing, and plant reliability.”
From being a back room spreadsheet exercise, metal accounting has become part of the feedback loop into the business. It means integrating existing PLC, SCADA, weighbridge, analytical and historical data logging systems. The data must then be fed into enterprise management systems to be easily accessible and comprehensible to all relevant personnel, wherever they are based.
“While not yet operating in real time, lead times on metal accounting information have gone from monthly to weekly and perhaps daily inputs.” Real time is not yet possible as the complexity of the metallurgical process, and the huge volume of data that it produces, slows the accounting process.
While metal accounting may sound straightforward it is not, and while smaller groups may still be able to get away with using a spreadsheet system, major mining companies will not. Metal processing has different process routes, and this is not linear, with different metal extraction systems taking different times. Metal accounting depends on sampling which introduces potential data inaccuracies, due to how representative the sample is or the accuracy of the measurement system and the assay equipment. Errors can sometimes be compounded, and the closer to the start of the process the more critical the error.
The idea is that metal accounting be able to help identify processing or technological problems. Knowing what should be in the system will give tangible information as to what might be broken.
Dariel, which sees about 20% to 25% of its business coming from the mining sector at present and which employs about 80 professionals, integrates companies’ metal accounting systems. Vercellotti says, while each company has its own systems and processes, there has been a bid to provide a uniform standard for metal accounting with a draft document of a code currently under review, AMIRA P754. The code aims to make the metallurgical process more transparent and to reconcile it with financial performance, so that the mining companies, auditors and investors can accept and compare data with greater confidence.
Vercellotti says that when Dariel goes in to upgrade a company’s metal accounting system, the first thing it does is audit and review exiting systems. Sometimes the gaps lie in the metal accounting systems themselves. “From there we look at the shape of what needs be done. This is a mile wide enterprise review on a very broad basis. We put out a report that covers the full breadth of what is required for a metal accounting system. Then we drill down to the technology that is required.” This typically includes a combination of best of breed systems, the company’s own systems, and custom developed solutions. “Or there can be one silver bullet solution, but 99% of the time there is no such thing.”
Typically there is a triangle upon which the implementation of a metal accounting system upgrade is based; project management, business analysis and the architecture.
The implementation is done on an iterative basis, with reviews done every three to six weeks. “We do the details of a package and then deliver that portion, and see if this concurs with the product the customer had in mind, and once we get confirmation we move on with the next step.” This avoids the inevitable disparity between what the developer thinks the client wants and what the client expects. “It is a much better approach than spending two years developing a system and then finding out where the differences are. It is important this process be done as a partnership between the mining company and the technology supplier,” Vercellotti says.
Mining companies all follow some process, though the data they use and the business processes differ in complexity. In many cases the technological backbone exists, but the processes have to be revised.
“In South Africa there is a big push to automate processes and bring in technology. About two years ago some of the groups began to implement metal accounting upgrades and have almost completed this process. Others have just started along this route.” Thus it remains too early to measure the results and how the upgrade of metal accounting systems has influenced companies’ forecasting abilities. From a continental perspective, Vercellotti does say the implementation of these systems is being done mainly in South Africa, as mining companies operating further north have very different methods and are not yet at the stage where such metal accounting upgrades are being considered.
Vercellotti says that apart from getting used to working with a new system there is little problem about organisations having to take pain to adapt to upgraded metal accounting systems. “Usually the organisation is in pain when it approaches us to implement a system, so they welcome the change.”