柴油加氢装置过程模拟与节能研究

Process Simulation and Energy Saving Method of Diesel Hydrotreating Unit

针对某炼油厂处理量为3.5 Mt/a的柴油加氢装置,应用Aspen Plus流程模拟软件建立了装置的数学模型,计算得出了与现场标定数据比较吻合的模拟结果。根据计算结果,利用夹点技术对其换热网络进行节能分析与改造。首先以夹点温差为20℃,确定换热网络能量目标。该装置换热网络的夹点温度为95.4℃,最小热公用工程量为5 085.7 kW,最小冷公用工程量为20 613.9 kW,与现有换热网络热公用工程13 870.8 kW相比,存在8 785.1 kW的节能潜力。然后消除违背夹点规则的不合理换热匹配,进一步优化,并提出了改造方案。该方案新增7台换热器,可节约热公用工程8 450.5 kW,约降低了60.9%的能耗,取得了良好的节能效果。回收期为0.67年。

Aiming at 3.5 Mt/a diesel hydrotreating unit in a refinery, the mathematical model of the device was established by Aspen Plus software, simulated results obtained by calculation were consistent with field calibration data. Based on calculation results, its heat exchanger network（HEN） was retrofitted by pinch analysis. When the pinch temperature difference was 20 ℃, energy target of the HEN was determined. The pinch temperature of the HEN in the unit was 95.4 ℃, the minimum thermal utility quantity was 5 085.7 kW, the minimum cold utility quantity was 20613.9 kW, compared with 13 870.8 kW thermal utility quantity of the HEN, there was energy-saving potential of 8785.1 kW. In order to eliminate irrational heat transfer matching that breached the pinch rule, the modification plan was put forward. In the plan, seven new heat exchangers were added, thermal utility quantity 8 450.5 kW was saved, the energy consumption was decreased by 60.9%.