How Many More Months Will It Run?

Aug. 24, 2009
Technology bolsters plants' quest to boost uptime.

Now probably more than ever, chemical makers are striving to boost efficiency and reduce costs. This is driving ongoing spending on asset optimization — and the release of new ever-more-powerful technologies designed to deliver it.

Since 2006 the worldwide market for Plant Asset Management (PAM) systems has grown 13% per year, or more than $400 million in value, says ARC Advisory Group, Boston, Mass.

That growth will continue, believes Wil Chin, ARC research director, because PAM systems offer users solutions that are appropriate both in good times and in today’s tougher economic climate. The challenge, he believes, is to properly get the PAM message across: “End-users understand that PAM can help them to predicatively diagnose the health of critical assets, but don’t always make the connection to how this can help improve profitability when resources are scarce and demand for their products is declining. Suppliers and end-users alike need to educate themselves about the benefits that PAM systems offer to help them survive the economic contraction.”

It was an effort to make just such a connection that led INEOS Chlor, Runcorn, U.K., which is the largest chlor-alkali producer in Europe, to undertake a major project with trip systems on its large chlorine compressor.

Before plant startup, 40 inputs into the compressor must be calibrated and tested. Each instrument on the compressor and the chlorine systems around it — monitoring conditions such as pressure, temperature and vibration — need calibration and then driving to the trip point to test the operation of the shutdown system.
The majority of the transmitters are on toxic gas duty and normally would have to remain in a completely clean and decontaminated state until the work was completed. Registered chlorine fitters then would re-joint the system in a highly controlled manner before pressure testing it for leaks. Having these people shadow the instrument team while shutdown tests were finished was very inefficient and time-consuming.

Traditional testing methods generally call for the majority of mechanical overhaul efforts to be completed and then instrument systems checked. With so many inputs to the system, the test duration was significant and prevented other work, such as pressure testing the system with chlorine, from continuing until it was certain that instrument tests were done.

Machinery Health Monitor

Figure 1. Wireless unit complements portable analyzers already used by maintenance staff.
Source: Emerson Process Management.

INEOS Chlor wanted to explore alternative methods of trip testing to remove instrumentation tasks from the critical path of the project. So the company turned to Emerson Process Management, Austin, Texas, and its PlantWeb digital plant architecture, which consists of field instrumentation communicating digitally via HART communications protocol to AMS Suite: Intelligent Device Manager. This made it possible to use the instruments’ simulation mode functionality and to remotely vary instrument output being read by the analog trip system. The instruments were decontaminated and calibrated during the mechanical outage. A dedicated team of instrument technicians and chlorine fitters then were able to reconnect, working methodically from one system to the next, rather than having to connect up piecemeal as each instrument was tested. Pressure testing could take place as soon as the fitters had finished. This simplified shutdown planning and reduced resource requirements significantly; it cut overall time to commission to just one week from two weeks, giving the company a whole week of extra production. “By using AMS Suite to drive the transmitter output we were able to test the trip system in parallel with other work that was going on. This shaved time off the overall schedule,” says Paul Young, INEOS Chlor automation manager. For Emerson, the future of asset optimization very much revolves around wireless-based solutions. However, even though traditional concerns about the technology are fading, hurdles still must be overcome. Stuart Harris, general manager of Emerson’s Plant Asset Management business, Eden Prairie, Minn., echoes Wil Chin’s thoughts when it comes to getting the technology message across: “Sometimes we talk about the customer’s wireless epiphany. Here, they start with a particular issue, for example pressure or temperature measurement. They then gain in confidence and realize that other issues drive reliability and interest in wireless begins to snowball. That’s the huge advantage of wireless technology: it is inherently scalable. Getting started is simple. You can get experience with just a few points and then move up in an extremely scalable manner.” Two new product launches emphasize the importance of wireless in today’s asset management market: the 475 Field Communicator and the CSI 9210 Machinery Health Transmitter (Figure 1). “The 475 device has moved earlier versions such as the 275 and 375 from device configuration into field diagnostics, for example, valve diagnostics — the sort of thing engineers want to do in the field. That’s one of the big step changes,” says Harris. The CSI 9210 is a wireless device that complements traditional portable analyzers and traditionally expensive online monitoring. “Essentially it provides a great opportunity at a price not achievable before. Remember that it doesn’t replace portable walkround technology but augments it. It is the wireless aspect that is the big enabler for this technology,” he adds. Harris points out that Emerson also is working in many other uptime-focused applications such as pressure and bearing temperatures. “This is very exciting: wireless technology opens up a whole range of opportunities to monitor in places you couldn’t before, for example cooling-tower fans and settling-pond agitators. Down the road, there will be a lot of other wireless-based diagnostic devices, too — for example to monitor corrosion.” Condition Management Is Key“The future is condition management because it helps move from reactive or preventive operations to a proactive and predictive environment,” says Kim Custeau, an Orange Co., Calif.-based consultant with Invensys Process Systems (IPS), London, U.K. “While there are many technologies that provide basic condition monitoring, it is field device management and the new breed of intelligent tools that enable condition management to improve asset performance in order to achieve specific business objectives.”
Scanning Valves
Figure 2. Ultrasonic sensor can generate an alarm to warn of an issue and record sound sample for further analysis.Source: UE Systems.IPS considers that condition management has three phases: collecting information, which is comparable to traditional condition monitoring; analyzing information to spot trends and areas requiring action; and acting on the results. Where condition monitoring focuses on gathering plant-level data and making them available as information, condition management goes the next step, advancing information to knowledge and action. “Condition management extends to fully integrate with DCS/PLC [Distributed Control Systems/Programmable Logic Controllers], safety and equipment diagnostic systems, ideally presenting information from these systems through business intelligence frameworks,” explains Custeau. An industry survey shows that, on average, unplanned outages result in a more-than-5% loss of production, she notes. For a plant with a production value of $50 million/year, this amounts to at least $2.5 million/year. “The role of condition management is to monitor the key assets, allowing the plant personnel to pro-actively deal with the issue before it causes a costly shutdown or outage. Using a conservative estimate of a 30% reduction in outages, this yields an annual return of more than $750,000.” This predictive capability is extended by condition management’s ability to collect key performance data to support reliability centered maintenance (RCM) analysis. An industry survey conducted by IPS suggests that more than 50% of preventive maintenance is unnecessary and, worse yet, often can introduce problems. “By analyzing the RCM data collected via condition management, organizations can reduce the level of unnecessary maintenance, delivering a further 10%-to-20% reduction in maintenance spending,” concludes Custeau. Technical AdvancesVendors continue to extend the capabilities of monitoring tools and thus help plants move to condition management. Consider, for example, ultrasonic monitoring. “Ultrasound technology is extremely versatile and therefore fits into any uptime program whether the emphasis is on mechanical, electrical or even fluid systems,” notes Alan Bandes, vice president, marketing, of UE Systems Inc., Elmsford, N.Y. “We have made advances over the years from primarily ‘point and shoot’ analog instruments to the digital age where digital instruments, supported by both data management and spectral analysis software, provide the capability of performing route-based inspections, data management, trending and even sound analysis.” Today, some digital instruments can upload route data that can be viewed and compared to current test conditions as an inspector moves from one test point to the next. In addition, some devices will generate an alarm if limits are exceeded, to advise the user of the issue while automatically recording the sound sample for further analysis. Data management software provides route data for creating reports and trend charts. Spectral analysis software allows users to review recorded sound samples to enhance their diagnostic process. Such software used with the ultrasound instrument enables a person to play the signal in real-time through computer speakers while viewing a display of the sound on either an FFT [Fast Fourier Transform], time series or waterfall screen. “This development creates many opportunities for users to expand the realm of traditional condition monitoring of mechanical operations to electrical equipment and even fluid systems such as valves (Figure 2),” he adds. [Bandes is co-author of the article on "Understand All The Costs of Gas Leaks".]
Temperature Sensor
Figure 3. Remote configuration reduces time and cost involved in installation and troubleshooting. Source: Raytek.Bandes sees interesting developments on the asset optimization horizon, too. For example, companies could share their data to create a diagnostic library of sounds, which would be a powerful tool. Even without such cooperation, far more analytics will be automatically carried out, with remote reports being easily and instantly generated, he believes. Further down the line, interfaces with humans will become simpler while technology integration will get much tighter once common standards are adopted. Smart control valves also are improving. For instance, Flowserve, Dallas, has launched the third-generation of its Valtek StarPac. The company claims StarPac 3 is the only fully integrated smart control valve on the market that provides full PID [Proportional/Integral/Derivative] control. Upgraded features include an explosion-proof housing, USB and infrared interface, updated electronics, stainless steel options and enhanced positioner functions. StarPac 3 gives users an integrated view of the process at a single point and reportedly can improve plant operation at a lower installed cost than conventional control systems. “The advancements in this third-generation product can potentially save facilities millions of dollars a year by providing a window into critical processes, allowing customers to reduce operating costs through integrated control and unparalleled diagnostic capabilities,” says Stephan Giesen, digital products marketing manager, Flowserve Flow Control Division. Meanwhile, Artesis, Cambridge, U.K. has increased the functionality of its motor condition monitor (MCM) system. It now features: wireless technology for cost-effective easy installation of monitoring stations in difficult locations — intelligent modems maintain reliable and transparent access with centralized users via the Artesis communications server; fully automated condition-assessment reports for even faster diagnostics — available within days after first installation; and the ability for engineers to quickly and easily customize applications for wider enterprise use. “The key benefit to our customers is that in-depth condition assessments containing detailed information about the nature and severity of all faults detected are automatically created and communicated to the team. More importantly, the reports also contain recommendations on the timescale of remedial actions,” says director Andy Bates. The reports, which are clearly presented on the display panel, can be emailed to appropriate people for immediate action. Finally, Raytek, Santa Cruz, Calif., has launched an integrated infrared sensor for continuous temperature monitoring (Figure 3) that the company says outperforms more-expensive competitive units. The new CM sensor reportedly allows tighter tolerances on heating processes — reducing heating costs while improving process throughput and product quality. This NEMA-4 sealed, single-piece integrated sensor is designed to measure target temperatures ranging from -4°F to 932°F. A built-in sensor health LED provides a convenient online indicator of the unit’s operating status and aids in troubleshooting initial sensor set-up. The sensor features remote configuration capability, reducing installation and troubleshooting time, and streamlining data acquisition. It also meets demands for sensors that can operate successfully in hostile or remote locations.

Seán Ottewell is Chemical Processing's Editor at Large. You can e-mail him at [email protected]