The process of producing catalysts is complex: a variety of chemicals must be combined to create a substance that causes a change in the rate of a chemical reaction without being consumed in the reaction. A minor mistake or variance in the process can result in costly plant shutdowns, wasted raw materials, and substandard finished products.
For more than 50 years, Danish company Haldor Topsoe has specialized in the production of a variety of catalysts and specialized equipment required for making such finished chemicals as ammonia, hydrogen, synthesized gas, methanol, formaldehyde, and sulphuric acid. The company operates facilities in Frederikssund, Denmark, and Houston, TX.
The Challenge
Haldor Topsoe's Houston facility manufactures more than 70 different catalysts for use in industries such as fertilizer production, mining, petroleum, and electric power. Developed in house, production ranges from 25,000-130,000 pounds per day, depending on the catalyst.
"Because of the number of products we make each day, we have a tremendous amount of documentation -- ranging from recipes to production orders to finished goods documentation," said Kirby Ducayet, DCS programming engineer, Haldor Topsoe. "With several operators running different machines, potential for variance among batches was high. Variances can degrade product quality and cause the makeup of the catalyst to differ from customer specifications."
Adding too much of one chemical can drastically change catalyst properties, resulting in downtime losses and extra material and labor expenses required to recreate the catalyst with the correct blend of chemicals. The ability to handle these complex process automation applications determined the effectiveness of the system.
"Not only are downtime costs high, but the materials needed to make a catalyst are expensive," said Ducayet. "To avoid unnecessary downtime and material costs, we needed a way to eliminate the variances in the batches and continue to keep the product quality above industry standards."
Although the company operates on a preset schedule to produce the various types of catalysts, it needed a solution that would also allow flexibility to change a recipe instantly in response to changes in customer orders or delivery demands. As a result, a vendor with expertise in process automation, as well as motion control and discrete automation, best meets their needs.
The Solution
Haldor Topsoe turned to Rockwell Automation for an innovative control system that would enable the company to restructure its workforce while producing consistent, quality products. The company also needed to increase the system's flexibility and expandability, with minimal production line downtime.
Leveraging the Logix Control Platform from Rockwell Automation, Haldor Topsoe upgraded its machines to include Allen-Bradley® ControlLogix® programmable automation controllers (PAC) using Rockwell Software® RSLogix™ 5000 programming software. The upgrade also included an operator interface workstation running Rockwell Software FactoryTalk™ View software, and Allen Bradley Flex™ I/O modules networked via a ControlNet™ network.
Part of the Rockwell Automation Integrated Architecture, the Logix Control Platform provides a scalable solution for the full range of automation disciplines, including sequential, motion, process control, drive control, safety, and information, using a common control platform. In Haldor Topsoe's application, the ControlLogix PAC manages overall control functions of the machines, as well as communicating information to the HMI for supervisory-level monitoring and control.
"We chose Rockwell Automation because we are familiar with the quality and reliability of the products and knew we could rely on their service and support," said Ducayet. "Rockwell Automation has a worldwide reputation for service and quality and we knew the company would be here in the future, so we could expand our capabilities by integrating our machines together."
Results: Increased Efficiency
The integrated system from Rockwell Automation helped achieve the company's goals of reducing batch variability, operating costs per batch, and overall waste during the production of catalysts. Tight integration between the programming software, controller, I/O and networks helped reduce development and commissioning time and cost.
"The simplicity and the flexibility of the architecture enabled us to increase our production capabilities," said Ducayet. "We can now produce consistent, quality products that exceed industry standards with less downtime and waste, which ultimately creates significant cost savings."
Since the upgrades, Haldor Topsoe has achieved significant improvements in all manufacturing disciplines throughout its Houston facility, including:
- increased overall plant efficiency by minimizing product waste, reducing variances and lowering operating costs;
- reduced batch variability, resulting in decreased operating costs per batch and overall waste during production;
- and simplified controls and operator interfaces, helping to reduce documentation requirements and simplifying overall control of machines.