Distributed Control / Operator Interface / PLCs & PACs / Batch Management

Chemical plants streamline distributed controls

Two major chemical manufacturers use the PlantPAx system to simplify their process control, optimize operations and virtualize computer tasks.

By Jim Montague, executive editor, Control

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You may not know what you've got until it's gone, but you may also not realize how bad you had it until something better arrives—especially if you've been struggling with legacy process controls. Fortunately, the PlantPAx process control system and FactoryTalk Batch software from Rockwell Automation are helping upgrade, simplify and optimize production at two major chemical applications.  

For example, Syngenta Crop Protection's agricultural chemicals plant in Omaha, Neb., expanded operations and upgraded over many years from mechanical to automated process controls, including interfaces running on a Unix emulator, Microsoft Windows and later NT via industrial Ethernet and central-level switches. Syngenta's systems engineer, Darrell Hanson, reported these incremental improvements in PLCs and HMIs made life better for the plant's operators, but their recipes remained in the same hard-coded versions and hardware they'd used since 1994, which made production inflexible and unable to handle changes or new products without new construction.

Also see: PlantPAx System: The Modern Distributed Control

"Orders were written by the QA lab at the start of each day, delivered to operations, accumulated through the year, put in a box and archived," said Hanson. "This system was easy to understand as long as we ran the same product and didn't make a lot of changes.

“However, it was cumbersome and any significant changes, such as adding an ingredient, changing a source, cooling in a different step or agitating longer, had to be hard-coded into ladder logic, which meant the process engineers had to ask the PLC programmers for help and new facilities had to be built,’ he said. “Additionally, historical data was limited, and could only be used for trending graphs, and the legacy hardware and HMI software was facing renewal.”

Hanson said the company was expanding their business and applications, so they really needed a more dynamic automation system and more flexible recipe management that could maximize existing resources, minimize the need to construct new facilities, and allow changes to be initiated by the process engineers so they could quickly meet customer demands.

“We also needed tighter controls to handle increased quality and environmental standards, improved analysis via historical data and reporting, and reduced field wiring costs for new installations,” he said. “This is why we went with Rockwell Automation for our system conversion."

Hanson presented "Boosting Process Control and Recipe Management with Batch Solution" at Rockwell Automation TechED 2015 at the Manchester Grand Hyatt hotel in San Diego, Calif. Created from the merger of Novartis and AstraZeneca's agribusinesses in 2000, Syngenta produces fungicides, herbicides and insecticides, as well as protective coatings for seeds. The Omaha plant is located on 42 acres with 26 buildings, six active formulation facilities and five tanks farms, including four outdoors and one indoors.

Hanson added that Syngenta's migration to Rockwell Automation began with its packaging lines in 2008, its liquid continuous unit in 2010 and some of the tank farms in 2012-14. Future conversions will include the plant's continuous granular unit, more tank farms and water treatment plant.

To upgrade its Omaha plant to more dynamic controls and flexible recipes, Syngenta worked with system integrator Interstates Control Systems Inc. in Sioux Center, Iowa, and implemented primary and secondary domain controllers and servers from Rockwell Automation, including:

    • FactoryTalk ProductionCentre on a SQL server running Java for shop-floor interfaces
    • FactoryTalk Metrics for OEE reporting,
    • Factory Talk AssetCentre for equipment,
    • FactoryTalk Batch
    • FactoryTalk View Site Edition
    • FactoryTalk Historian
    • Factory Talk VantagePoint reporting software running on a VantagePoint SQL server

All of these servers reside on ESXi virtualization servers running VMware software. Syngenta also adopted a thin-client computing strategy and Allen-Bradley PanelView graphic terminals for all production sites and stations.

"Our new PLCs are programmed modularly, so recipes can control groups of equipment following the ISA S88 standard," explained Hanson. "New recipes are set up by formulation engineers instead of PLC programmers. Orders are entered into campaign manager software by QA lab personnel for each batch to be produced, and operators start and control all batch functions using FactoryTalk Batch.

“All data is recorded using FactoryTalk Historian, and batch reports and KPIs are viewed with FactoryTalk VantagePoint,” he said. “We're adding 10 new products every year, and our old hard-coded PLCs just couldn't cut it, so we had to get to a more flexible recipe management and control system. Admittedly, there's some paper we can't get away from, and so we still use physical batch tickets, but all our data is recorded on FactoryTalk Historian, and FactoryTalk Batch gives us more flexibility in combining formulations, such as combining lighter and heavier or more and less dense materials. Our HMIs can still see deviations and errors, but now we can automatically adjust for greater accuracy, and view batch reports with better trends, X-Y plots and all sorts of charts.

Overall, FactoryTalk software and the PlantPAx distributed control system, along with other supporting solutions, gave the company faster time-to-market and improved asset utilization because they could use the same tanks to make more and different products, reduced their total cost of ownership, and reduced their enterprise risk management, he said.

Jost combines, virtualizes process control  

Going a virtual step further in the St. Louis area, the controls engineering department at Jost Chemical Co. in Overland, Mo., recently worked with system integrator McEnery Automation (http:// http://mceneryautomation.com) in Fenton, Mo., to combine and upgrade Jost's distributed process controls, and migrate to the PlantPAx process automation system built on virtual, redundant servers. However, its consistent design and configuration—and virtualized data processing—also saved $20,000 in upfront engineering costs, enabled real-time data and analytics gathered across multiple buildings, aided troubleshooting, reduced downtime by 5%, and eased operator training. 

"The controls engineering department was asked to deliver more usable production information to process engineers and production managers on the business network, and to standardize operator interface graphics throughout the plant's 15 production lines to facilitate easier operator transitions between production areas," said Rick Tissier, chemical engineering leader at Jost. "We determined that we really needed to restructure our entire plant control system architecture because our existing system limitations included multiple control platforms, isolated process areas, insufficient historian capacity, custom and inconsistent PLC and HMI code, and an overloaded process network with a flat architecture.

"We also needed to restructure our controls because, in the past five years, we've grown from being a $20 million company to being a $60 million company,” he said “We want to be $100 million in the next few years, and our old controls couldn't handle this growth."

Tissier and Steve McNamer, project manager at McEnery, presented "Jost Chemical Deploys Virtualized PlantPAx" at Rockwell Automation TechED 2015 at the Manchester Grand Hyatt hotel in San Diego, Calif.

Jost was founded in 1985, and its 220 employees manufacture 7 million kilograms per year of high-purity, inorganic salts for pharmaceutical, nutritional, food and specialty markets. Its more than 250 products include ammonium, calcium, copper, iron, magnesium, potassium, sodium and zinc.

McEnery Automation and its 20 control system engineers help manufacturers gain a competitive advantage through the strategic use of automation by understanding each client's processes and equipment, identifying challenges and problems, applying its automation experience, and offering solutions that control, monitor, analyze, and integrate process systems. McEnergy is certified by the Control System Integrators Association (CSIA) and is a recognized Rockwell Automation system integrator.

Tissier explained that Jost's objective was to build a plant-wide control system that could be implemented in phases over a year or more, and when complete:

    • Make existing licenses compatible
    • Give its historian access to data from all existing process areas early in the project
    • Be flexible enough to allow integration of future process areas
    • Enable consistency in programming and operator graphics throughout the facility
    • Generate cost savings via efficient implementation tools
    • Increase plant reliability 

"We like migrating devices and capabilities we've purchased previously," said Tissier. "We're starting two more production lines this year, and so we've got to have consistent programming and graphics. That's why we wanted to create models and templates for FactoryTalk VantagePoint and FactoryTalk ViewPoint. They also allow us to create most of our reports in-house for maximum knowledge retention, minimize capital expenditures, and use McEnery's software expertise, which we're very thankful for." 

Tissier added that the Rockwell Automation Library of Process Objects—such as device configurations from templates, predefined alarms, VFD faceplates and sequencer AOI—was the determining factor in Jost's decision to standardize on Rockwell Automation.

"Also, the existing FactoryTalk Historian was underutilized because of limited access to process data due to processing capacity and network limitations,” he said. “Excel's add-in trend tool loaded on the process engineers' computers was the only means of data access, so no reports were configured, and available process data wasn't being used."

McNamer reported that Jost basically had one process, un-segmented control system for all its applications and devices, and much of its production traffic was colliding and interfering internally. The plant's process controls consist of three Allen-Bradley ControlLogix PACs and two Allen-Bradley CompactLogix PACs, eight SLC/MicroLogix PLCs, 29 Allen-Bradley VFDs, 16 I/O chassis, three PanelView graphic terminals, six standalone FactoryTalk View Site Edition station servers, and one server running FactoryTalk Directory Services and FactoryTalk Historian.        

Before virtualization, Jost had five physical servers. To virtualize its computing, the company dispensed with three of the original servers, dedicated one to FactoryTalk Historian with access to data from all process areas, and used the last physical server to establish eight virtual servers running Hyper-V software for control and supervisory tasks. FactoryTalk VantagePoint provides process data to managers on Jost's business network. Also, seven existing switches were configured for virtual local area networks (VLANs), 10 network switches were added for increased network segmentation, and a SonicWALL firewall was used as a gateway to Jost's business network. 

"Using the library reduces implementation time for new and converted processes and provides consistent operator interfaces," said McNamer. "It also enables Jost to convert existing process areas one at a time by converting existing ControlLogix programming and FactoryTalk View SE standalone applications to the PlantPAx format, and then integrating them into distributed FactoryTalk View and ViewPoint."

"We also wanted to do most of the upgrade in-house, so Jost could maximize knowledge retention and minimize costs," added McNamer. "The migration path needed to allow software licenses to be reused and/or reapplied, as well as achieve version compatibility required throughout the project."

As a result, Tissier reported that the library has reduced Jost's programming costs by 25% for an estimated savings of $10,000 over three process areas. Using Hyper-V reduced its required Windows Server licenses for an estimated savings of well over $10,000 for server hardware and software. 

"Our historian tag count has increased to 750 tags," said Tissier. "Our engineers are using FactoryTalk VantagePoint to suggest process improvements and additional automation, and the PlantPAx system has simplified the implementation of these suggestions. In addition, our increased automation has resulted in higher productivity by reducing batch time and operator errors, but our operators are requiring less training on graphics.

"Our maximized precipitation rate reduced product rework by 5% and minimized time in centrifuge by 10% through improving cycle times, while monitoring electrical power consumption data resulted in increases in scheduled production without exceeding peak power limits, which reduced our power costs," added Tissier.

"Additionally, we increased automation of sequencing to reduce batch times up to 10%, while milling improvements resulted in more consistent product size and increased on-stream time by 6%. Also, optimization of our drying process has shortened drying times by 10% andimproved consistency of product moisture. Analysis of process data allowed identification of operating conditions, which had been causing quality issues for one product code. Corrections resulted in a 10% reduction in rework."