催化裂解装置3.5MPa蒸汽系统节能措施分析

Analysis of Energy Saving Measures for 3.5MPa Steam System of Catalytic Cracking Unit

中海石油宁波大榭石化有限公司2.2Mt/a催化裂解装置是全厂的耗能大户,3.5MPa过热蒸汽是其主要能耗之一。不同于常规的催化裂化装置,由于其特殊的工艺条件:反应深度更大、转化率更高、富气产量远大于常规催化裂化,汽轮机3.5MPa过热蒸汽耗量大量增加,其3.5MPa蒸汽无法自己自足,需要外购130t/h左右蒸汽以生产满足需要。结合催化裂解装置的特点通过采取降低吸收稳定操作压力、优化分馏二中循环取热、烟机轮盘冷却蒸汽改造、优化原料配比等措施,达到了降低3.5MPa蒸汽的消耗的目的。

The 2.2 Mt/a catalytic cracking unit of CNOOC Ningbo Daxie Petrochemical Limited Company is a large energy consumption for the factory,and the 3.5 MPa superheated steam is one of its main energy consuming units.Different from conventional catalytic cracking unit,due to its special technological conditions:greater reaction depth,higher conversion rate,and far higher gas rich output than conventional catalytic cracking unit,the 3.5 MPa superheated steam consumption of the steam turbine increases greatly,and the 3.5 MPa steam cannot be self-sufficient by itself,so it needs to purchase about 130 t/h of steam to meet the demand.Combined with the characteristics of catalytic cracking unit,the consumption of 3.5 MPa superheated steam can be reduced through the following measures:reducing the operating pressure of the absorption stabilization system,optimizing heat recovery from middle circulating reflux of fractionator,reforming the steam cooling system of the steam turbine wheel,and optimizing the proportion of raw materials.