Using a single raw material, natural gas, the Georgia based ammonia plant for PotashCorp, PCS Nitrogen, is the largest producer of nitrogen products on the East Coast. Since its start-up in the late 1970’s this plant has become one of the most reli- able ammonia plants in the world, and now produces over 2.8 million tons of ammonia and ammonia based products each year.
The Challenge: Reduce Maintenance and Expansion Costs and Increase Functionality with Zero Downtime
“Ammonia is a commodity chemical and typically the margins are not great,” offers Keith Wilson, Ammonia Technology Manager at PCS Nitrogen, “so the keys to making money are having a very efficient plant and having a very high stream factor. And this plant has had a stream factor in the 98 to 99 percent range for the last three to four years.”
By the end of the ‘90s, however, the plant required a major upgrade in its con- trol systems – the 1970’s vintage computer system was demanding a great deal of money in maintenance dollars just to keep it running. For the plant to protect its incredible on line record, the control and monitoring systems had to be replaced and improved.
Implementing ACP Technology
Replacing the aging, unreliable com- puter system (which provided the operator interface) with state-of-the-art DCS tech- nology decreased current 5 minute scan times to under 10 seconds. Moving to Thin Client technology at the same time allowed PCS to easily and inexpensively distribute the new displays throughout the plant while still being able to use their lega- cy Windows software. Adding additional monitor screens simply means plugging in a new Thin Client – no software has to be installed or even modified.
One of the central elements of the plant’s original control room was its panoramic display – the several walls of gauges and alarm panels that make up this feature have long been a staple of chemical processing plants. PCS realized that there were substantial economic and perform- ance benefits to be realized if some of the existing instrumentation could be replaced with Thin Client hardware, so they began using Thin Client technology to give the operator the look and feel of single loop controllers and strip chart recorders at approximately one-third the cost.
“With ACP Thin Client technology,” offers Anderson, “we can deploy lots of small, single entity monitors that give our operators the panoramic view they want at a much reduced cost.” Combined with the additional monitors, Thin Client technology serves the partic- ular needs of PCS Augusta perfectly. In most cases, the user cannot tell the dif- ference between a Thin Client applica- tion and an application resident their own machine. All this without a single day of lost time production.
“Our intention at this point in time is to continue to use the Thin Client tech- nology when we implement the DCS sys- tems throughout the plant,” says Anderson. Using Thin Client technology to provide multiple monitors gives the operators a better insight into their process. PCS also plans to use the Thin Client technology to give operators a view of the entire process from any location, using field mounted, hardened monitors on all their local control panels through- out the campus.
At PCS Augusta, plant operations move continuously, and so does all of their man- ufacturing data. The combination of the new DCS system and ACP Thin Client tech- nology gives PCS a competitive edge . . . and keeps their business operations smelling sweet.