Wireless Comes of Age

According to Nicola Ribon, a project engineer at Lundbeck, the company began by monitoring three wells using a wired solution, but when the project expanded, and those wells on the periphery of the plant were included, wireless became the answer. "Because of the distances between those wells and the recorder, we chose a wireless solution. Moreover, a couple of wells are outside the grounds of the facility in the middle of the street, so it was impossible to reach them with cables."

Timing was another factor in the decision. "We needed to use the system for only a short period, probably a year," explains Ribon. "After that we can reuse the wireless system to collect and record other kinds of data. That's not possible with cables; you need to dismantle them."

The wireless technology is from Endress+Hauser and is based on the WirelessHART protocol. "Basically [we chose these products] because we just used Endress + Hauser level transmitters for the first cabled application. We know the performances of these transmitters, and we choose to maintain the some partnership with E+H also for wireless application," Ribon explains.

Oil and gas giant Petronas, based in Kuala Lumpur, Malaysia, is running a pilot project at its granular urea plant in Gurun, Kedah province. According to A. Aziz B. Ahmad, project engineer, "We are using wireless applications to monitor pressure and tank levels. We're using it to bring local information back to the control rooms."

As with many wireless converts, cabling plays a big role in the decision to cut the wires. "We run out of spare cable," Ahmad says simply. He adds that knowing that wireless technology was going to be used only for monitoring and not for control was also a factor in making the move. Although wireless for control is certainly a possibility in the future, for now, no one is ready to take that leap.

Ahmad says that his team had the choice of going with either the WirelessHART or the ISA 100.11a protocol, and they chose ISA 100, or more accurately, they chose technology from Yokogawa, which uses the ISA 100.11a protocol.  The standards issue didn't really arise, says Ahmad. "Yokogawa was the first to offer their transmitter," he says.

The company also offered significant backup and support.  "Yokogawa played a critical role in getting us comfortable with the standard and the wireless field technologies. They have conducted site surveys, given the appropriate support and even imparted valuable knowledge to our engineers during installation phase," says Ahmed.

So far, Petronas' experience has been a good one. In fact, says Ahmad, "We are satisfied with the progression and the proposed solution this far and are seeing smooth integration between Yokogawa's wireless products and our existing system. We will explore the expansion of wireless in our operation, as we are seeing very positive throughput with the wireless solution installed in our plant. In fact we have added another wireless installation for tank level measurement and upgraded our PRM system to enjoy more asset management benefits."

Other Uses

Wireless isn't just about remote connectivity. Another focus is on diagnostics. Over the last year or so, the MOL Plc Danube Refinery in Százhalombatta, Hungary, has been developing a strategy for expanding the use of wireless in its operations with a focus on two areas, monitoring and diagnostics, says Gábor Bereznai, head of instrumentation, control and electrical at the refinery.

Keeping an Eye on the Tank Farm Figure 3. At Lubrizol's Deer Park, Texas, facility, temperatures and pressures at the tank farm are monitored wirelessly. Courtesy of Lubrizol

MOL will be monitoring corrosion, the temperature of fire heaters, the efficiency of heat exchangers, temperature and differential pressure transmitters and the open/closed position of valves.

The MOL refinery was the 2010 HART plant of the year, so it already has a strong infrastructure of wired HART devices, but there were some problems. Bereznai explains, "We had positioners we couldn't use because the gates between the positioners and the DCS were not HART-ready. Our explosion-proof barriers weren't HART-ready either."

So the company went to Emerson for THUM modules (The THUM can be retrofit on any existing two or four-wire HART device, enabling wireless transmission of measurement and diagnostics). The THUM adapter "allows us to get around this problem," says Bereznai.

The THUM adapter also allows MOL to connect many of its field devices to its Emerson AMS asset management system, and in another adaptation, meet government emissions reporting requirements. "We created an app where we can use pyrometers and THUM adaptors together to measure emission rates," says Bereznai.

And don't forget safety and security functions. Wireless monitoring of eyewash stations and safety showers, as well as personnel location, is an easier sell, perhaps, than applications such as monitoring and maintenance. Such applications are available from many vendors, including Honeywell, Emerson, Apprion and BS&B Industrial Wireless Solutions, among others. 

Glitches

As effective as these solutions are, getting them running is not all roses and lollipops. As with any new technology, there are glitches in the system and a learning curve.

Honeywell Sensing's Citrano observes, "Early on people had bad experiences with wireless because it wasn't really fit for the purpose. When you got into discussions with people [we found] reliability and security were issues. Battery life was a problem too, but as people get better at setting up their networks—they would have too much messaging going over one node—as they get more experience, they can avoid these problems."

Lundbeck's Ribon reports, "At the beginning we had some problems with communication between some repeaters/adapters; we discovered some radio noise due to a huge radio antenna place about 300 m from our facility. We solved the problem by moving some repeaters in areas where there was less interference and by placing some shields near the repeaters."