South Korea's Samsung Fine Chemicals let a contract to MDC Technology, Teesside, UK, for a model-based predictive controller, to be installed at Samsung's methyl amine plant at Ulsan, South Korea.
The project, which MDC Technology will perform in collaboration with its strategic partner AID Corp., is designed to improve overall plant operational stability, maximize unit throughput, and reduce energy usage, said MDC.
To achieve this, it will stabilize fractionation-column temperature profiles, reducing standard deviation by at least 50% in key locations; and reduce energy consumption by at least 5%.
Additional control system objectives are:
- Controlling the nitrogen-to-carbon ratio in the synthesis section.
- Maintaining recovery-column temperature profiles within tight ranges.
- Minimizing steam use in recovery columns.
- Maximizing fresh ammonia feed.
- Maintaining unit operation within operating constraints.
- Eliminating disturbances caused by unit pressure changes or recycled material flow rates.
The system runs on the Windows NT platform and is based on SMOC (multivariable optimizing control).
"This technology provides effective control of multi-input-output processes," said MDC. "It uses a dynamic process model of the system to predict future plant behavior. At any point in time, SMOC evaluates the inputs and outputs of the process and calculates the best set of moves for the control variables that will minimize error from set point, keep the process within constraints, and at the same time optimize the economics of the unit in question."
Andy Bell, an MDC consultant, said, "Samsung was impressed by the use of intermediate variables within SMOC and the ability to effectively reject disturbances on a complex process plant....Costs were minimized, as SMOC on-line controllers were embedded within the existing infrastructure."
Operators will use the control system via the plant's Yokogawa DCS interface. Three controllers will be built to maximize on-line availability.
