Chemical plant avoids fugitive emissions with wireless valve monitoring

With 28 branches in 20 US states, the core business of Harcros Chemicals is the distribution of industrial chemicals. The Harcros Organics Division produces surfactants, emulsifiers, defoamers and myriad specialty products at the plant site in Kansas City, Kansas.

Harcros uses manual valves for sampling, directing, injection and extraction processes at its Kansas City plant. Many of the valves are in hard-to-reach places that are too costly to access with cables. Monitoring was a difficult process requiring operators to travel into hazardous areas, climb up ladders and visually check the valves’ state or position.

Worker safety is a primary concern, not only because of the location of the valves but because of the toxic chemicals the valves contain and control. The facility uses propylene oxide and ethylene oxide for its processing operations, and exposure to either one can irritate a person’s eyes, skin or respiratory tract. Leaks involving toxic chemicals can also result in hefty fines. Plus, the facility must pay cleaning, rework and disposal costs of up to $25,000 per incident.

Sample and drain valves, for example, are opened and purged before and after a batch. Some product may be released, or leaked, during this process, and a new batch begins every eight to 16 hours. Besides the product losses, Harcros managers incur downtime and clean-up with each incident. The facility needed a better, more flexible and less expensive way to monitor its isolated, manual valves.

For an Emerson Process Management field trial, Harcros added a Fisher 4320 Wireless Position Monitor to a manual valve in its propylene oxide production unit. The device monitors the valve’s position throughout the range of travel, communicates wirelessly via gateway with an existing DeltaV digital automation system and eliminates the need for visual inspections.

This Fisher 4320 wireless position monitor installed in the ethylene oxide unit is about 3.5 m off the ground.

“This project was about eliminating mistakes and increasing safety. Wireless valve monitoring with the Fisher 4320 device enabled us to reduce inadvertent emissions and bad batches, as well as avoid the high cost of rework, clean-up and lost material. Eliminating these costs - which average about $25,000 per incident, not including fines - is a good thing for our plant,” said Kevin Root, Unit Manager at Harcros.

The Fisher 4320 WirelessHART-communicating device is an easy-to-install instrument that monitors valve movement throughout the range of travel and provides frequent, wireless updates about the valve’s position. The wireless signals are delivered automatically, reducing the time and risk associated with visual inspections. Harcros installed 22 units on manual valves in the propylene oxide and ethylene oxide areas. The goal was to improve monitoring for all the reactors and all the critical points in the process.

Adding the 4320 wireless position monitors enabled Harcros personnel to identify valve issues and prevent chemical leaks before they could result in fines, production delays or clean-up costs. The Fisher 4320 wireless monitors easily integrated into the site’s three-year-old DeltaV digital automation system and Smart Wireless solution, including a Rosemount wireless gateway and AMS Snap-On wireless applications.

The 4320 field-trial units helped Harcros-KC avoid three product release incidents, saving at least $75,000 in clean-up costs. The ability to monitor and control manual valves wirelessly has also enhanced safety, improved the ease and accuracy of audit reporting, and reduced the fines associated with inadvertent emissions.

Lloyd Hale, Director of Manufacturing at Harcros Chemicals, is very happy with the results of the project and sees Harcros using more wireless instruments in the future.

“The 4320 instrument field trial established our confidence about the reliability of wireless technology. We now believe that the more devices you add to a wireless system, the more robust it becomes. Besides applying the Fisher 4320 to more of our manual valves, we would consider Emerson Smart Wireless technology for tank level management, rail-car monitoring, and a host of temperature, pressure and flow applications at the Kansas City site,” he said.