Wireless Application: Western refining cuts wiring costs, improves performance
At Western Refining’s Gallup, N.M., refinery, process unit and tank operations have been upgraded using an advanced wireless mesh network. Based on Western Refining’s experiences, wireless is a desirable alternative in applications where traditional copper wiring can increase cost, maintenance, and unreliability. With wireless, plant infrastructure investments are reduced and the return on investment (ROI) can be significant. Projects that previously could not occur have become worthwhile.
As the only active refinery in the Four Corners region, Western’s Gallup facility primarily relies on a locally produced, high-quality crude feedstock known as “Four Corners Sweet.” This crude supply is supplemented with feedstock from outside the area.
The operation is situated at nearly 7,000 ft elevation on rocky and mountainous terrain. Production processes and storage facilities cover a large geographical area, so instrumentation for monitoring the refinery’s remote offsite units can be very costly.
The Gallup refinery uses a legacy Honeywell TDC 3000 Distributed Control System (DCS). Management sought to extend monitoring capabilities to remote tank farm areas. The cost of traditional wiring and conduit for monitoring outside storage units was estimated at $15,000 to $22,000 per tank.
Up to 90% of the installed cost of conventional measurement technology can be for cable conduit and related construction. With wireless field devices, wired infrastructure is largely unnecessary. Using industrial wireless solutions reduces process monitoring costs, allows connection to points that are physically or economically difficult to access, and permits easy expansion for additional measurement or actuation points for the cost of a transmitter. Security is robust, power management and multispeed monitoring are predictable, and Wi-Fi coverage is provided at no additional cost.
Industrial wireless technologies:
- Revolutionize process measurement
- Offer new opportunities to optimize plant performance, reliability, and safety while reducing installation costs
- Provide, with addition of wireless transmitters, an affordable and accurate alternative for applications involving supervisory control, monitoring, indication, and alarming
- Can operate in the most demanding plant environments with recent advancements in radio technology and communications protocols
- Bring self-healing wireless mesh networks to numerous industrial applications, beyond wireless-enabled versions of conventional field devices for process automation.
In 2008, the Gallup refinery began implementing a wireless solution that incorporates a multiprotocol, multistandard wireless network communicating simultaneously with Wi-Fi and industrial I/O devices. It also uses optional redundant synchronized gateways, which link the wireless network into the process control network (PCN).
The wireless “backbone mesh” architecture incorporates field- and plant-level applications on one, unified network. The network uses externally powered multinodes scattered throughout the coverage area. The devices support industrial wireless standards for process control applications and provide sensor data transmission redundancy at all levels.
Multinodes communicate with each other and provide a backhaul for bringing information to a gateway, where it passes into the larger wired PCN. The meshing action takes place between multinodes, not at the instruments. For safety, at least two multinodes receive data from each instrument, creating a redundant path.
Before the wireless installation at the Gallup refinery, an on-site survey determined the project scope and challenges. The survey addressed the coverage area desired at the plant, existing power and network infrastructure, and the implementation goals (immediate and long-term), and assessed interfering and operating frequencies currently in use or ambient in the environment. The survey also identified any potential security exposures.
Gateway, 38 instruments
The multifunctional wireless mesh network implemented at the Gallup refinery supports a variety of applications within one network. Wireless technology was first employed for tank gauging and is now being introduced for high-level analog and digital indications in the process units. Wireless monitoring data is integrated into the refinery’s existing DCS and advanced applications.
Wireless transmitters have replaced outdated pneumatic devices used for valve positioning and process variable indication. An optimized wireless infrastructure with narrow band radio frequency hopping ensures maximum performance. Wireless devices transmit measurements to a base radio connected to the plant control system.
Western Refining’s current installation includes one wireless system gateway and four redundant multinodes connecting 38 wireless instruments. The wireless field devices send information to a series of multinodes, creating a mesh infrastructure that maximizes uptime and data security.
At the Gallup refinery, wireless transmitters have broken down barriers to monitoring variables in areas where traditional hardwired transmitters were too costly, difficult, or time-consuming to implement. Instruments are designed for applications that are without access to power, are remote or difficult to access, require frequent changes in instrumentation schemes, or where manual readings are typically taken.
With wireless transmitters, engineers at the refinery can easily increase the number, frequency, and type of measurements. In addition, they can improve accuracy and consistency of measurement by replacing manual readings with automated online data collection. Online communication with the control system also helps ensure precise time tracking of information for use in troubleshooting process problems.
For Western Refining, wireless has proven to be a desirable alternative to traditional copper wiring, which increases cost, maintenance, and unreliability. ISA100 DSSS wireless transmitters can be used to monitor a variety of processes and assets in hazardous and remote areas, and this data can be used in a variety of systems.
Wireless frequency-hopping spread spectrum technology also adds security and ensures that noise interference at any one frequency does not block communications or cause security concerns. One scalable wireless network conserves spectrum and power.
The wireless installation was fast, inexpensive, and easy. Operators, engineers, and technicians have one system to learn, operate, and maintain. Wireless allows plant personnel to react quickly to changing conditions and gather information they need to optimize processes. Plant infrastructure investments decrease immediately, and significant ROI can be realized. I/O costs have been significantly lowered, and projects that previously could not occur now become immediately worthwhile.
By 2011, Western Refining plans to install more than 100 wireless transmitters throughout the Gallup refinery for various process monitoring tasks, as well as noncritical control applications. Wireless instrumentation will be installed on at least six more process units. The first control-related wireless applications will be in offsite blending.
At Western Refining, wireless applications have helped to optimize plant productivity and reliability, improve safety and security, and ensure regulatory compliance. Much more than just avoiding the cost of wire, the key value of wireless lies in the ability to integrate valuable data into existing control systems and advanced applications, while also sharing that data with other networked applications.
Reginald Joseph is senior process controls engineer, Western Refining.
Western Refining used Honeywell, Automation and Control Solutions, Process Solutions products, including the OneWireless System and XYR wireless transmitters.
About Western Refining
Western Refining is an independent oil refiner and marketer headquartered in El Paso, Texas. The company has a combined crude oil processing capacity of approximately 221,000 barrels per day (BPD). Its refineries and affiliated companies serve a broad customer base in Arizona, southern California, Colorado, Nevada, New Mexico, western Texas, Utah, and the U.S. Central East Coast region.
Western Refining’s production operations, which are concentrated in the Southwestern and Mid-Atlantic regions of the U.S., produce high-value light products such as gasoline, diesel, and jet fuel. The company markets under its own brands of Giant, Mustang, and Sundial.