Crude fouling is a long-standing operational problem in a refinery, which can seriously affect crude preheat train efficiency and its operation. Plate heat exchangers (PHEs) are considered to mitigate fouling. Meanwhile, velocity is an important factor that can simultaneously correlate fouling rates, heat transfer and pressure drop. Therefore, in this work, a methodology is carried out to optimize the velocity distribution and find the best places to replace shell and tube heat exchangers by PHEs. To achieve this, a velocity correlation model suitable for PHEs is established. The problem is analyzed in the entire operation time horizon, which is divided into several time intervals to describe the dynamic nature of fouling. Simulated Annealing (SA) is used in this optimization method. A case study is illustrated to show the capacity of the method and the optimization results are analyzed in detail.

原油结垢是炼油厂中长期存在的运营问题，会严重影响原油预热机组的效率及其运营。板式换热器（PHE）被认为可以减轻结垢。同时，速度是可以同时关联结垢率，传热和压降的重要因素。因此，在这项工作中，采用了一种方法来优化速度分布并找到用PHE代替管壳式换热器的最佳位置。为此，建立了适用于PHE的速度相关模型。在整个操作时间范围内分析问题，将其分为几个时间间隔以描述结垢的动态性质。此优化方法中使用了模拟退火（SA）。