Emerson Exchange 365

The chemical manufacturer Univar kept running into a costly dilemma on two of their tank farms in Ontario, Canada. They found the problem, but to fix it, they would have to adopt an entirely new approach for measuring their tank inventory.

Positive displacement level monitors that they were using to measure the inventory inside their tanks were designed with a floating device attached to an overhanging arm that would frequently get stuck, throwing off their tank measurements.

Inaccurate and unreliable measurements were leading tank farm managers to misinterpret product levels causing inventory management problems including, overfilling, off-spec batches, contractual issues, order delays, and customer concerns.

In addition, because of the flammable solvents being produced, regulations restricted maintenance staff to manually scaling the tanks to perform level checks, which created billing meter inaccuracies and presented safety risks.

At the 2016 Emerson Exchange in Austin, Lewis van Kamp – a technical sales specialist for Emerson local business partner Lakeside Process Controls – will explain how Univar is now embracing wireless guided wave radar in his presentation “Taking inventory Management to the Next Level Wirelessly.”

“Several plants and refining facilities around the world are making the switch to this technology as a more efficient and reliable alternative for tank management and custody transfer,” van Kamp said. “For companies like Univar, product quality is key, so operators need accurate information and real-time monitoring to ensure the highest inventory justification.”

The solution was to install Emerson’s DeltaV distributed control system and replace all field level devices with a wireless radar system.

The flexibility of the DeltaV system allowed it to link with Univar’s legacy system to install wireless radar switches on tanks that were identified to be the most problematic without disruption to the rest of the site. The switches would protect against overfill while wireless temperature and pressure transmitters were added for mass balance of inventory and addressed product thermal expansion concerns. It would also run the tank master software and had AMS capability for full control of field devices and alarms for tank level issues.

The solution created less intrusion into the sites’ restrictive areas. It also allowed tuning and visualization of the radar’s understanding of the tanks with a networkable and password-protected system that allowed Emerson service technicians remote access to devices for troubleshooting.

By using wireless radar, temperature and calculations performed on the DeltaV system have enabled them to automate their inventory management for two plants with plans to automate the inventory management county-wide with auto refill orders from their customers.

In addition, wireless radar has the reduced time and resources required to manually check level and justify inventory outdoors and for multiple sites.

Univar is now approaching 100% inventory accuracy, which has freed up resources for process improvement. Due to flexibility of the system they plan employ this solution at all sites across the country and install automated replenishment of their customers’ feedstock.