(182c) Optimization of Mixed Smr Plant Using Advanced Modelling & Six Sigma Tools to Enable Smart Manufacturing: Case Study
AIChE Spring Meeting and Global Congress on Process Safety
2019
2019 Spring Meeting and 15th Global Congress on Process Safety
Process Development Division
Modeling Tools and Techniques for Process R&D II
Wednesday, April 3, 2019 - 2:20pm to 2:45pm
In this paper, an implemented optimization of mixed steam reformer in the oxo-alcohol production process case study is presented. An Aspen Plus model based study has been performed to optimize the mixed SMR plant operations for the existing feed gas composition. Then, coupled the model-based study with six sigma tools to develop the best operating conditions and zone for various scenarios. A number of contour diagrams have been developed for these scenarios using MINITAB, and response surface optimizer has been developed using response surface methodology. In this part, optimized the steam to carbon ratio, carbon dioxde to natural gas ratio, using surface response methodology using MINITAB, and the optimized conditions are translated into operator language and implemented in the systematic procedure. The implementation of the optimized conditions resulted in savings of energy 0.22 MMBTU/Ton of product and production increase of 2000 TPA.
Furthermore, a detailed dynamic model, as in the DCS of the plant, has been developed ASPEN DYNAMICS and analyzed the effects of the feed gas disturbances on the process. The analysis showed that H2/CO ratio in synthesis gas, reformer energy efficiency, methane slippage, and oxygen content in the stack gases would have serious repercussions and dynamic profiles have been developed for various feed gas compositions changes. In addition, it has been understood that a proactive advanced feed forward controls are necessary for reformer temperature, methane slippage, H2/CO ratio along with the existing feedback controls. Feed forward based control loops have been added on top of the existing controls based on the carbon number and calorific value of the feed gas. These upgradations enable the smooth operation of the plant during drastic feed gas composition changes. The added advanced process control would eliminate the situation of process upset and un-planned shutdowns, that result in improved equipment integrity and reliability.