"Do we do it the old, reliable way, or do we challenge ourselves to demonstrate new technology and use continuous improvement?" That was Kevin Dahm's question.
Dahm, a principal engineer in the Major Enterprise Projects (MEP) division at DTE Energy (www.dteenergy.com), recently faced this issue while adding control room architecture to the flue gas desulfurization (FGD) equipment and controls on each of the four 800-megawatt, coal-fired units at its Monroe Power Plant near Detroit. The FGD process scrubs power plant emissions by using limestone slurry as a reagent to convert SO2 in the flue gas to a gypsum byproduct, which is then available for use in drywall, instead of ending up as landfill.
Adding FGD technology to Monroe's four units also required significant control integration within the existing control room footprint. "An early, in-house design used space within the existing Unit 3 and 4 control room to co-locate the FGD control room," says Dahm. "However, plant operations and the project team had a significant learning opportunity and developed lessons learned based on two years of Units 3 and 4's FGD operating experience. We recognized that we had one last chance to get the design correct and incorporate DCS capabilities, advanced technology and human-factor best practices into Units 1 and 2's design. This final design is planned to sustain the plant for the next 30 years of operating life."
As a result, Dahm, his project team and plant operations developed a decision document and criteria that focused on a centralized, combined FGD control room philosophy, which included all four unit-specific FGD controls, as well as all common equipment shared by those plants, such as conveyors, air and water systems. The team worked with operations, enlisted a consultant, Human Centered Solutions (HCS, www.applyhcs.com), and ABB (http://us.abb.com) to specify its 800xA DCS control system. The team worked on control room design, appropriate HMI colors, lighting, monitor locations and followed ISA's (www.isa.org) 18.2 guidelines for alarm management and situational awareness. HCS is one of the 14 members of the 20-year-old Abnormal Situation Management Consortium (ASMC, www.asmconsortium.net).
However, they weren't out of the old-control-room wilderness just yet.
New Gizmos, Persistent Problems
As the design debate at DTE Energy shows, there are several tectonic shifts shaking the world of control room design as its inhabitants strive to embrace the future:
- Many smaller and formerly separate control rooms are merging into larger, centralized "control and collaboration centers;"
- New interfaces and networking are allowing operators to perform more control room-type tasks remotely and move operators further away from their process applications, which can help improve safety;
- Tablet PCs and other handheld interfaces are allowing operators to take more control room data and functions into the field; and
- More accessible and voluminous data and more powerful software are enabling modeling and simulation to get much closer to real-time optimization.
These earthquakes in control room design and capabilities are enabled and driven by the same faster, cheaper data processing and networking that's transforming most process control applications and other industries. However, even though smart phones, tablet PCs, 3-D displays, closer-to-real-time simulations, video game-style interfaces, "augmented reality" devices and other new tools are becoming available to help in the control room, they can't substitute for a complete assessment of an application's requirements thorough planning before construction, and meeting the functional needs of its operators.
Think, Plan, Then Build
While it's logical to think that industrial facilities should be built around their operators for maximum efficiency, such has not been the case throughout history. Manufacturing structures, including process applications, were all built around big-ticket equipment, and operators and technicians were thrown in as an afterthought. Even now, most control rooms are built first, many screens are added and optimum arrangement is considered last—if at all.
"Builders try to arrange their large screens so people can see them, so they're usually driven to theater-style displays without thinking about the best ways to support control room activities," says Dr. Peter Bullemer, a past principal investigator at ASMC and senior partner at HCS. He and his colleagues at ASMC stress that new and renovated control rooms must seek to meet the cognitive and physical needs of users and support their ability to stay alert and aware—even though users don't want to change from what they had before.
"Preference doesn't equal a performance requirement," adds Dr. Dal Vernon Reising, also a past principal investigator at ASMC and senior partner at HCS. "Operators used to want dark control rooms and black-background screens, and today they want to sweep their hands over software objects on huge flatscreens, but neither means they're getting a sense of where their process application is actually at."