基于Aspen Plus的蒸汽透平网络模拟和优化

针对乙烯装置蒸汽管网用能过程中存在的不合理现象,采用Aspen Plus化工流程软件对其中的蒸汽透平网络进行了模拟和优化.通过对单个透平的模拟,分析了透平抽汽量、进汽温度和排汽压力等操作条件的变化对透平效率的影响.在此基础上模拟了蒸汽透平网络,并以透平抽汽量为自变量、透平网络总进汽量为目标变量,通过MATLAB-Aspen Plus接口工具箱使用粒子群优化算法(PSO)对其进行操作参数优化.采用智能算法,避开了因在Aspen Plus中设置过多约束作为设计规定而导致模型不易收敛的不足；对于约束条件的处理,通过对不满足约束的粒子加以惩罚来实现.优化结果表明,在满足透平输出功率以及低等级管网蒸汽用量需求的前提下,通过合理分配各透平的抽汽量能够有效地降低透平网络超高压蒸汽(SS)消耗量,优化后的透平网络可减少超高压蒸汽用量0.6吨/小时.

Simulation and optimization of steam turbine network with Aspen Plus

According to the unreasonable phenomena in the steam piping network of ethylene plant,the steam turbine network of the device is simulated and optimized by the chemical process software,Aspen Plus.The influence of operating condition change on turbine efficiency is discussed through simulation of the turbine,such as extraction steam flow,into steam temperature,exhaust steam pressure.Based on the results, the steam turbine network is simulated and optimized by particle swarm optimization through the interface toolkit MAP,while extraction steam flow for independent variable and the total into steam flow for target variables.Using intelligent algorithm,the defect of model’s not easy to converge is avoided,which is caused by setting too much constraints as Design Regulations in Aspen Plus.The optimization results show that in the condition of meeting the same output power and the requirement of the other pipe networks,the steam consumption of supper-high-pressure(SS) could be reduced effectively by selecting the extraction capacity of every turbine reasonably.The turbine network optimized could decrease 0.6 ton SS consumption per hour.