Perpustakaan Digital ITB

Wax is a long-chained alkane able to become a solid under the temperature called wax appearance temperature (WAT). This solid can be deposited on the inner part of a pipe. Wax deposition mitigation can be done using insulator and electric heater. It is so important since wax deposition implies to inner diameter reduction and pipe roughness increase. Hence, the design of insulator and electric heater must be technically and economically optimum. To reduce trial & error in using commercial simulator, this study proposes an efficient method to make designing process easier. In this study, mathematical model is made to construct the method. The main design principal for insulator and electric heater are similar. This modeling is developed based on heat transfer equation combined with economic equation. This model is then validated by using simulator that will be able to do more complex and realistic calculation. Model fitting is conducted by applying correction factor to the model. The method is then implemented for a field case and it is reported that the method used can give an economically optimum design for insulator and electric heater applications. Short number of iterations were able to converge the calculation to the minimum cost. A correction model is required for the insulation. The correction can be done by either adding a margin on the outlet temperature (by 15 F for this case) or adding a margin to the insulator length (by 200 m for this case). Therefore, this innovative method is proven to overcome the problem in designing the mitigation plan for wax deposition.