The company’s asset management and historian software perform better predictive and preventive maintenance by analyzing historical and real-time data.
By Deanna Nord, Contributing Writer
Imagine flying over the alpine forest of the Rockies to the red mesas of the Southern Ute Reservation in southwestern Colorado. There you will find Red Cedar Gathering’s Arkansas Loop natural gas treating plant in the San Juan basin.
Red Cedar Gathering is a midstream energy company, one of the largest in the region, with treating capacity of about 250,000 MCF, or 250,000,000 cubic feet per day. The company “gathers” the gas from more than 1,200 wells at 25 sites over 895 miles of pipeline using 150,000+ horsepower of compression to deliver gas to the plant, where the gas then is treated and delivered to various interstate transportation pipelines.
Phil Velasquez, systems manager, Instrumentation, and electrical engineer for the company, manages and monitors this entire process beginning to end on his computer or work tablet. Velasquez and his team monitor the incoming and outgoing gas flows, temperatures, levels, pressures and equipment, which make up a growing 10,000 live and 8,300 historical data points.
“What prompted us to seek other solutions,” says Coy Bryant, director of operations at Red Cedar Gathering, “was that our former configuration was labor intensive.
“We sat down as a team to look at how to streamline our entire companywide control system,” he continues. “We then decided to eliminate most of the third-party controllers and historian software.”
They now use the FactoryTalk® View human-machine interface (HMI) graphical interface from Rockwell Automation with a custom-configured HTML5-based Asset Performance Management home page screen created with ReadyAsset CMMS software by LLumin Inc., an Encompass™ Product Partner in the Rockwell Automation PartnerNetwork™ program.
“Before we changed out the third-party software, updating and maintaining data on operations in the old system was clunky, and the data was limited,” agrees Velasquez. “We already used FactoryTalk Historian ME from Rockwell Automation, and 85% of our controllers are still the Allen-Bradley® CompactLogix™, the SLC™ 500 controllers and a few from the ControlLogix® 55 series of controllers. It was easy to expand and integrate LLumin software from there.”
“We converted to LLumin software, FactoryTalk View SE and ME, and FactoryTalk Historian SE and ME to provide the operators more historical and real-time data and better diagnostics,” explains Velasquez. “We designed a reliable control network where we use DH+™, ControlNet®, Modbus™ TCP and EtherNet/IP™ protocols. We standardized the PLC control communication to EtherNet/IP.”
Natural Gas Treatment Primer
Let’s review what happens in the natural gas treatment process. Natural gas streams out of the ground containing CO2, water and other contaminants, all of which must be removed. The carbonic acid — created by the combination of CO2 and water — corrodes pipelines.
CO2 also reduces the British Thermal Unit (Btu) value of the gas, which is unmarketable in concentrations of more than 2% or 3%. The treating facility removes the “rich” gas containing CO2 and water to create “lean” or pipeline-quality gas.
Red Cedar Gathering uses amine heaters to increase the temperature of an amine media liquid, made of MEA (monoethanolamine), MDEA (methyldiethanolamine), DEA (diethanolamine) and other solvents. The amine liquid moves through the heater to make contact with the natural gas. A chemical reaction binds the amine liquid to the CO2, and the CO2 is ushered out of the system.
Using a similar chemical absorption process, the energy firm uses triethylene glycol (TEG) as the dehydrating agent. The TEG binds with water molecules and removes the water. Now the gas is pipeline-ready.
The energy firm deployed the IIoT-enabled asset management software 3-1/2 years ago. With the additional data it’s gained with the software, it has increased its run time above 99%, resulting in plant throughput of 100% per year.
“We require less labor hours due to fewer callouts with equipment going down,” Bryant explains. There is less downtime due to alerts on the equipment condition and operations. We paid for our investment of integrating LLumin within 3 years.”
“Our labor hours are reduced due to a quicker start time with dehydration equipment and amine heaters,” Velasquez adds. “Now we can start and stop quickly from our control system. It is automated where we did it manually before. It reduces the time to bring up the system.”
Before the software integration, if the TEG or dehydration equipment went down, the team would repair and diagnose the equipment manually. If a pump was malfunctioning, a team member would go to the pump, examine the issue and provide the required data over a radio to the control room and thus allow a system restart.
The operations team members monitor the dehydration equipment and BMS pumps from the control room. They run through their checklist to start or restart the system, and they can see whether moisture or CO2 levels are increasing. They receive alarms in the control room, analyze what’s happening and decide on the best course of action.
Velasquez uses the PLC and HMI to view the location and condition of equipment that provides color-coded and symbol alerts on the need for inspections, maintenance or repair.
“We set the alarms higher than the pipeline industry standards,” explains Velasquez. “We then ensure that only pipeline-quality gas continues beyond the plant.”
“Interlocks” and “permissives” on the system prevent valves from opening or pumps from starting. On the interface, the directions will be to check specific equipment and identify any problem. If everything checks out and fits the parameters, they will start again from the control room.
If there’s trouble with a piece of equipment, it will be locked out of service so no accidental starts occur. In other words, the system won’t allow a restart on that equipment to proceed until the necessary repairs or replacements are made. If the repair will take more than a few minutes to address, they leave that equipment down and start up another.
Predictive and Preventive Maintenance
Red Cedar Gathering uses the asset management and historian software to do predictive and preventive maintenance by monitoring and analyzing historical and real-time data such as temperatures and pressures.
“The additional data helps us keep a close eye on the condition of the equipment,” says Velasquez. “We now proactively measure the condition of our equipment and set historical and condition-based rules. We record machine data to see the condition of our equipment and use preset rules to identify out-of-spec conditions.”
The energy company stipulated what it needed to measure and observe based on historical and real-time data. It does regular inspections and preshift machinery checks. It also can view trends in machine condition, look for potential problems and set alerts for follow-up.
“We can also now analyze the data and optimize the treating capabilities. We keep tighter thresholds on temperatures now and have a more efficient burner management system,” affirms Velasquez. “Our pumps are designed to maintain a consistent pressure and run efficiently. With the data, we can monitor the pumps 24/7 and identify any irregularities.”
With the Asset Facility View module, Velasquez and his team can view, locate and manage critical equipment. They can also upload interior photos and architectural drawings.
The company uses the data gathered through the asset management software to track equipment and facility conditions. The software looks at assets essential to the operation, which ones are nearing the end of their life cycles and forecasts how soon they need to be repaired and replaced as well as the costs.
All of this information improves equipment life span of and helps the energy company in purchasing equipment, Velasquez explains. From the historical data, leaders can see what equipment was used, how many run hours it had and how it performed.
With minimal training and using the services of a local system integrator, it was a smooth process to incorporate the asset management software and make all the changes to the system, agree Bryant and Velasquez. In upgrading the system, Red Cedar Gathering required flexibility to interact with the existing in-house PLC standard logic, various types of vendor PLC logic, and the legacy PLC systems by Rockwell Automation. It also needed the software to be compatible and scalable for use in both the FactoryTalk View SE and ME environments.
“We changed our HMI and our OPC database,” says Velasquez. “We upgraded our operator interface and legacy Allen-Bradley PLCs to allow for quicker HMI response time and better diagnostics.
“We standardized HMI FactoryTalk SE and FactoryTalk ME to help operators with their daily routine,” he continues. “The upgraded HMI is a more detailed and intuitive graphical interface between our personnel and the PLC. It allows for better monitoring, controlling and diagnosing of the real-time field data to improve the process at the plant. The software is designed to mimic the employees’ workflow.”
For parameter file handling, the team determined that each I/O Type and Point would need a separate parameter to provide better diagnostic tools for operations and to historize the data points on the control network.
The Red Cedar Gathering control system currently has about 2,250 parameter files in service and about 1,475 parameter files in testing phase. This design allows for secure isolation between the corporate and the control system network. The control network pushes the read-only data to the corporate network for monitoring, diagnosing and viewing.
This integration continues with ongoing migration of the existing and new systems into the control system. There is ongoing standardization of the HMI layout and graphics using FactoryTalk View SE and ME and ongoing standardization of the PLC hardware and programming style.
“We changed the manual gauges to transmitters, and we now have more transmitters in our facility.” says Velasquez. “We monitor plant-wide through LLumin View SE and ME and FactoryTalk Historian SE and ME. Together, they collect all the information from the controllers. The process makes the data readily available for decision-making.”
LLumin, Inc. is an Encompass™ Product Partner in the Rockwell Automation PartnerNetwork™ program. The firm provides high-performance enterprise asset management (EAM) and materials tracking software solutions.
The Journal From Rockwell Automation and Our PartnerNetwork™ is published by Putman Media, Inc.