- Bondan Revlioxa (NRP. 2311 100 198)
- Syauqi Fibiano R. (NRP. 2311 100 199)
Chemical Engineering FTI-ITS
- Prof. Ir. Renanto Handogo, M.S., Ph.D.
- Juwari Purwo Sutikno S.T., M.Eng., Ph.D.
Natural gas is the non renewable energy source. Therefore it must be controlled, otherwise, it will be completely run out if it doesn’t well utilized. One of the process unit that must be controlled is the natural gas separation unit, where there is an depropanizer column. Now there are many configuration control structure to control depropanizer column. There are mildly that used temperature control for the inferential control from the composition control. For the multi-components separation, temperatures at appropriate locations in a distillation column can often provide fairly accurate information about the concentration of the key components. However if there is no correlation between the overall method of analysis of the temperature control thus occur off-set of mole propane in product stream for every given disturbance, with the result structure with composition controller will be used to maintain propane mole fraction from both product. And for the fast and better result the modern technique which combine with ideal/basic composition control, which is cascade. Therefore the capabilities of cascade must be research and will be compared with its original ideal/original controller to control the distillation column for natural gas. There are 3 structure which have been made in this research, Structure 1 which has temperature controller, Structure 2 with cascade composition / steam flowrate controller (CC/SFC), and Structure 3 which only has composition controller without cascade. The tuning method that have been used were Ziegler-Nichols and IAE. The result of calculated IAE parameter will be determine which structure gives the fast and stable respond between Structure 2 and Structure 3. From research, Structure 2 gives more stable and faster respond compared with Structure 3, also there is no offset in Structure 2 but rather Structure 3 still have offset for disturbance FFD-20%. For Structure 1 it gives offset for all disturbance variable given. In conclusion, the IAE parameter results for Structure 2 will be smaller than Structure 3 and Structure 1. And from the research, the IAE result give the smaller error for all disturbance variable given is IAE tuning method.
Keywords : cascade, depropanizer, distillation, disturbance, IAE, natural gas, Ziegler-Nichols