Industry: Mining

Richards Bay Minerals using new HMI situational awareness technology

Goals

  • Reduce process safety risk
  • Critical operational information highlighted and operational team empowered
  • Effective management of process control alarms
  • Create awareness of ASM to end user (production)

Solutions and Products

  • Wonderware System Platform 2014
  • Wonderware InTouch 2014 (With situational awareness library)
  • Wonderware Historian 2014
  • Web-enabled Alarm Management
  • ACP ThinManager

Challenges

  • Dealing with change and aspects of human nature
  • Getting acceptance of the solution

Results

  • Mitigation of process safety disasters
  • Improved alarm management
  • Improved abnormal situation management
  • Reduction in cost of operations while maximising business value
  • Standardisation of control systems
  • Improved overall operational effectiveness
  • Improved operator skills and capability
  • Enhanced operational teams’ decision making process with correct information

Richards Bay, South Africa – where Richards Bay Minerals (RBM), a world leader in sand mining and mineral processing operations, produces titania slag, rutile, zircon and high purity iron which all have properties essential to the manufacture of a wide variety of specialised and space-age products. RBM currently has the capacity to produce approximately two million tons of products annually, including approximately 100,000 tons of rutile and 250,000 tons of zircon. At any one time, no fewer than 20 large ocean-going vessels are either at anchorage awaiting loading or on the high seas, transporting RBM’s products to customers across the globe.

HMIs – responsible for more than you might think

On the afternoon of March 23 2005, the BP Texas City refinery in Texas was rocked by a series of explosions when a distillation tower in a hydrocarbon isomerisation unit flooded and sent a geyser of liquid into the air, producing a cloud of highly-flammable vapour that was promptly ignited by an idling pickup truck. Fifteen workers were killed and 180 injured. The blast shattered windows in a 1.2 km radius.

With specific reference to the HMI screens used at the plant, the U.S. Chemical Safety and Hazard Investigation Board (CSB) found that there were no overviews, no trends, inconsistent colours, no condition indications and a flood of alarms. In essence, the CSB declared that the mimic was “essentially just a PID segment sprinkled with live values”. The “fix” included paying about $2B in fines and another billion in complying with findings and regulations.

In January 1992, the crew of an Airbus A320 mistook “Vertical Speed” mode for “Flight Path Angle” mode and the aircraft struck a mountain resulting in the death of 87 of the 96 passengers and crew. Among several items officially cited as causes for the tragedy was the operator interface,

Were these tragedies due to human error or were the operator interfaces partly to blame? Increasingly, ineffective or misleading HMIs are being cited as causes in industrial accidents.

Project Requirements

RBM decided to implement recommendations from both the handbook and from Wonderware to address:

  • Finding a resolution to ineffective alarming
  • Improving the display of relevant information
  • Standardisation of graphical symbols
  • Simplifying the operation of systems
  • Improving the effectiveness of operators
  • Empowering operators to make the right decision at the right time

“These are major topics that can’t be effectively resolved without engaging the people who matter,” says Aidan. “That means establishing interaction requirements for the operators and then designing an effective display where they can visualise what’s happening at a glance – and then repeating the whole process to make sure we’ve got it right.”

Implementation

The pilot project was implemented at a mining pond with the aim of clearly defining KPIs for graphics levels 1 – 4 and simulating their impact on operators. “Our current level 1 graphic is as shown in figure 2,” says Nkosi Zikalala, PCS Technology and Innovation Specialist, RBM. “It’s full of colour and crammed with numbers but far less informative than its new equivalent in figure 3 which, though less colourful, gives a concise view of plant performance and highlights only those KPIs that matter. Figure 4 is the operational KPI (level 2) view of the same original graphic.”

All displays are grey and devoid of complexity and confusion showing only the information relevant to the user. In this way, any colour attracts the viewer’s attention and the colour used (red, yellow, magenta, etc.) is a standardised indication of the severity of the anomaly.

Figures 4 and 5 show the original and new Surge Bin graphic. Note that there is no attempt to reproduce how any of the plant items (pipes, valves, etc.) look in reality as in the original graphic. Only the key operational parameters are shown and values are represented graphically as much as possible.

For example, at the lower right of figure 5 is a symbol showing displacement – this is known as a “Polar Square” symbol which is part of the standard situational awareness library supplied with InTouch 2014. Ideally, the four values should be between the small centre rectangle and the larger one but the “Left Rear” value has exceeded the prescribed limit. Not only is this anomaly immediately visible because of the distorted shape (rather than a bunch of numbers), but it is highlighted in red to show that it needs urgent attention.

During the initial proof-of-concept deployment, a book was left in the control room where operators could log their views and feedback. These are some of the comments received (the added comments are by Kevin Aidan):

  • Confusing mimics – Unfamiliar symbols were bound to create some confusion at first
  • Mimics are too abstract – The operators are familiar with the shapes and forms representing the real-world plant objects
  • Display not bright enough – The development had been done in a completely different environment and lighting condition to the control room
  • No colour – Previously, the presence of colour meant little because of the colourful and realistic displays. Now the mere presence of colour means that operator attention is required and the colour used dictates the degree of that attention
  • Can’t see the burner flame – Operators can see the flickering orange / red flame of the burner– but this isn’t a KPI. The KPI for the burner is temperature which governs product quality, not the colour of the flame
  • Improved alarm management – Operators previously saw flashing alarms as a distraction and their removal, together with the prioritisation of alarms, were welcome
  • Create our own trends – Operators can now create their own trends depending on their changing requirements

“The feedback from the senior leadership team was positive as they approved the implementation plan while the CEO of Rio Tinto Iron and Titanium wanted to know what was required to move the implementation plan forward,” says Aidan.

Conclusion

HMIs are the primary interface operators have with the processes in their charge. These displays are in constant use and changing them is bound to meet with some resistance and that’s why operators should be involved at every step of the migration to situational awareness HMIs as well as in the FAT. “To change behaviour, it first has to be motivated and then entrenched with habit,” says Aidan.

On the other hand, this initial resistance to change is offset by faster and easier determination of the current process situation, relevant rather than distracting alarms, uncluttered displays and a focus on the information that matters rather than impressive graphics or “essentially just a PID segment sprinkled with live values”.

“This is the first step in an information management process which must move up from the SCADA / HMI level to MIS, MES and beyond,” concludes Aidan.

Benefits

  • Mitigation of process safety disasters.
  • Improved alarm management
  • Improved abnormal situation management
  • Reduction in cost of operations while maximising business value
  • Standardisation of control systems
  • Improved overall operational effectiveness
  • Improved operator skills and capability
  • Enhanced operational team’s decision making process with correct information

Background

Actions are based on decisions which are, in turn, based on information. The source of the information is unique and independent of the way it is represented – and that’s where the problems start. How does one display information that is meaningful, required and actionable in real-time all the time?

HMIs are supposed to do just that but the most sophisticated HMI systems can sabotage the bottom line and are potentially deadly if they confuse operators, don’t deliver the level of needed information as and when required and make a mockery of alarms by flooding operators with non-prioritised and unscreened events. Rio Tinto’s Richard Bay Minerals (RBM) cut through complexity and confusion with an effective alarm management solution backed by the latest HMI concept involving situational awareness – this is where pretty pictures leave and serious information takes over.

“As technology improved, the complexity of control systems grew as we made them increasingly sophisticated to improve processes while at the same time introducing the opportunity for errors,” says Kevin Aidan, PCS Superintendent, RBM. “The cure for this was to introduce even more sophistication and automation in a vicious circle. The result is that when things go wrong now, operators have difficulty fixing the problem and so we blame them for the consequences of what have become known as ‘abnormal situations’.

According to Aidan, an abnormal situation is a disturbance or loss of containment with which the control system can no longer cope without intervention. This can have tragic as well as financial consequences including multiple fatalities and personal injuries together with an impact on process safety, equipment damage, product quality, increased production costs and decreased employee job satisfaction through their helplessness to cope with situations beyond their control.