Lonmin’s plant near Rustenburg is in the business of mining and processing platinum and the family of platinum group metals. It is a non-stop operation that relies on the effectiveness of a vast control system which, in this case, was approaching the end of its useful life. Lonmin looked for a solution that would not only provide a risk-free migration from legacy to modern technology, but would also provide the future-proof scalability and flexibility it required.
Project goals
The main objective was to replace the existing ageing iFIX scada system with a modern solution that would provide world-class technical and operational functionality and allow Lonmin to define, deploy and maintain automation standards while improving system up-time and on-line development time. In other words, the project needed to deliver an award-winning scada migration utilising the maximum functionality the chosen solution could offer, on time and within budget constraints.
Risk management and other challenges
Lonmin considered this a risky project because of the migration to a new system. This was not an upgrade but a replacement of extensive facilities, 250 000 I/O would have to be reconfigured and 450 scada screens would need redevelopment using a new automation standards library still to be developed. This all had to be achieved in a short period of time with the ever-present threat of production losses.
The existing PLCs were to remain and the plant should not be stopped at any time during commissioning, therefore the old and new system would need to be run concurrently until the operational personnel was satisfied that the new system had at least the same functionality as the old system.
Solution selection
Although Wonderware was already a de-facto standard with Lonmin, it could only be considered as a solution if it met the system design and performance criteria as well as all other project requirements. Once the Wonderware offering had proved that it would address the required issues, the company was appointed to manage the project in total. Another factor in Wonderware’s favour was the additional software the company could offer to add benefit to the installation.
“It was important that the delivery of the project was done through our channel partners while minimising risk,” says Percy French, Lonmin automation manager at the Marikana smelter. “So Lonmin followed stringent selection criteria and, because of the large scale of the project, Control Systems Integration, Hatch Africa, Iritron and Quad Automation were the system integrators selected for the implementation, while Wonderware Southern Africa managed the project. Since the new system would be based on the Wonderware System Platform using ArchestrA technology as well as InTouch Scada/HMI and the Wonderware Historian, it was important that all system integrators were certified professionals on these products.”
Implementation
The project was implemented over eight plant areas (each with dedicated redundant servers), 11 operator/control room view stations, 10 remote panel view stations and 25 manager view-only stations linked to Terminal Server.
Wonderware managed the project end-to-end, developed the user requirement specification and detailed design specification, developed the necessary templates and was responsible for the quality control of the delivery of the project. Wonderware Southern Africa allocated consultants to help develop the required documents as well as all the required standards, and also teamed up with the Global Delivery Team from Wonderware USA in order to leverage capabilities in developing an ArchestrA Standards Object Toolbox for Lonmin. This US team had completed a number of these projects in the past and their experience and participation would contribute to the delivery of a successful project.
The second component consisted of developing the templates to be used for the necessary new scada screens, modifications to the PLC code in consideration of the new ArchestrA objects, and finally, the ArchestrA objects themselves. These ArchestrA objects would form the Lonmin toolkit which would be used by the SIs later in the project.
Three SIs were appointed to instantiate the templates on the estimated 530 scada screens using System Platform graphics and 300 000 I/O items on the plant. The plant was divided into three equal parts in terms of I/O with the first SI responsible for the slag plant, the receiving and blending section and the filter plant. The second was responsible for furnace No. 1, utilities and Pyromets, while the third tackled the converters, the sulphur dioxide plant as well as the Wonderkop and MV substations.
A unique navigation and menu system was developed that would be intuitive for the operators and need the minimum of keystrokes to access the required functionality. The system is connected to the plant intranet which has control room and remote office viewing nodes. Drivers from Software Toolbox were used throughout and the old and new systems ran concurrently until the team was comfortable to initiate switch-over.
“In my view, the outstanding features of this new system include the management of standards, its scalability and the ability to complete development work on multiple fronts with multiple SIs simultaneously,” says French. “This allowed accelerated development with the project starting in October 2010 and the migration being completed by July 2011 and we have been busy with a programme of ongoing enhancements ever since. In hindsight it would have been even more expedient to bring the various SI development teams to a single location rather than have them work remotely, this would have helped resolve issues quicker.”
Regarding the development, deployment and maintenance of standards, French said that they could always be improved but there came a time when a design freeze needed to be imposed to prevent delaying the project. “It is best to regard standards as evolving entities that will be refined on an on-going basis after system commissioning.”
Future plans include enhancing the graphics, review the alarm strategy, incorporating various capital projects into the system, integrating QI Analyst for Statistical Process Control and using the Information Server portal to publish graphics and reports.
Benefits
* Enhanced performance.
* Single set of standards.
* Easier maintainability.
* Superior reporting and delivery.
* Fully supported and constantly current software.
* Ensured continued operation of production processes.
Conclusion
The modernisation of any company’s core wealth-creation processes is justifiably looked upon with trepidation by production and financial management alike. Production management is worried because of the magnitude of the task and the ever-present threat of production stoppages. Financial management is concerned about the expense of such a move and is also worried about the loss of income and goodwill production stoppages could cause.
This large scada modernisation project at Lonmin’s Marikana plant proved that migrating from legacy to modern technology can be done without any interruption to production and that initial financial concerns are dwarfed by the confidence that the company’s wealth-creating machinery will continue to operate uninterrupted for the foreseeable future.
For more information contact Jaco Markwat, Invensys Operations Management, +27 (0)11 607 8100, [email protected], www.iom.invensys.co.za
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