عنوان مقاله [English]
Fouling in heat exchangers is main causes of energy losses in oil and gas refineries. One way to reduce this energy loss in these refineries is to predict fouling resistance. In this paper, the fouling resistance rate is first estimated using the Buckingham's dimensionless groups. The resistance rate is then validated with the experimental data derived from
the literature. The results show the relative error of 26.79% with the experimental data, which is rather low and acceptable as compared by those reported in the literature ranged from 40-59%. In general, by estimating the fouling resistance rate, the fouling threshold curve can be plotted and the position of the exchangers relative to it can be checked. The position of the exchangers would allow to reduce the amount of fouling and to stay in non-fouling area with the proper justifications of the operating conditions. The curve is also used to estimate the deposition resistance in the unstable state with the asymptotic model. This model has also been validated with the experimental data from the Australian light oil and Tehran refinery data. It is worthy to mention that the prediction of fouling instability has been less considered in the literature, although with this estimate it is possible to have a better and more regular cleaning program for exchangers and to reduce the problems caused by deposition in exchangers leading to lower operational costs.