作　　者： ; ;

机构地区： 惠州学院化学工程系

出　　处： 《计算机与应用化学》 2011年第1期1-5,共5页

摘　　要： 本文采用经济学模型来描述跨装置热集成问题,该模型以集成的换热网络和长距离换热匹配费用最小为目标。通过适当提高中间物流进料温度,不仅可避免该物流"在上游装置冷却,下游装置重复加热"的能量利用现状,还可节省一组换热设备投资。若允许物流跨装置热匹配,长距离换热匹配的管线投资会增加,但可获得全局最大能量优化。本模型通过逐步逼近的方法来求解最优出料温度。首先,设定一个较大的步长δT,改变进料温度,计算换热网络的总投资,根据计算结果可绘制进料温度曲线;随后,从曲线中缩小优化区间,设定一个小的δT,在这个小区域内重新计算总投资、迭代数次,可得到优化出料温度。应用案例来验证模型和计算策略的实用性,中间物流温度从50℃提高到97℃,整个系统中的能量利用效率显著提高。由于进料温度提高,下游装置高温能量空余出来,这些能量可输送至上游装置替代热公用工程加热物流,热集成后的系统总投资比装置单独操作降低了20.15%。 An Exergo-economics mathematical model for heat integration across plants is presented. The model is considered total cost of integrated heat exchanger network （HEN） and long distance matches. The paper studies area heat integration in respect of HEN synthesis. Properly rising up the feed temperature （FT） of intermediate stream, the energy using process of the stream ＂usually cooling in upstream plant, then heating in downstream plant＂ is avoided reasonably. But the total annual costs are increasing as the FTs rising if heat integration across plant is forbidden. To achieve total site energy optimization, heat integration across plants is permitted. Approaching optimum FT method is introduced to solve the model. Firstly, setting a large δT, changing FTs and calculating total cost of HENs, the optimal FT curve is drawn based on the results. Then, narrowing the optimum range from the curve, seting a small δT and calculating the total cost in the closed optimum area. Iterating several times, the optimal FT can be obtained. The application of the model is illustrated with an example. The FT is raised from 50℃ to 97℃. Energy using efficiency is improved obviously in the integrated system. The high temperature energy in downstream plant is saved because of FT rising. The energy is sent and replaced the hot utility in upstream plant. The total annual cost of integrated design is 20.15% less than the plants stand-alone operation.

关 键 词： 火用 经济学 数学规划 换热网络 热集成

领　　域： [化学工程] [理学]