操作压力对初馏塔前换热效果的影响  

INFLUENCE OF OPERATING PRESSURE OF HEAT EXCHANGER BEFORE PREFLASH COLUMN ON HEAT EXCHANGE EFFICIENCY OF CRUDE OIL

作　　者：贾超杰[1] 刘艳升[1] 濮昕韵 邬乐欢 

机构地区：[1]中国石油大学(北京)重质油国家重点实验室,北京102200

出　　处：《石油炼制与化工》2016年第1期86-92,共7页Petroleum Processing and Petrochemicals

基　　金：国家自然科学基金面上项目(21176248)

摘　　要：换热器中原油汽化经常会引起一系列问题,国内炼油厂参考国外先进设计经验,在原油进初馏塔前增设憋压阀门,以提高换热器压力,解决原油汽化问题,但是操作压力的提高对换热效果存在一定影响。利用PRO/Ⅱ软件对规模12.0 Mt/a常减压蒸馏装置的阀门憋压操作状况进行模拟分析,结果表明:换热器进口压力由1.2 MPa升至2.2 MPa时,原油从换热网络中回收的热量降低8.24%,常压炉负荷增加1.65%,常压塔塔顶冷凝系统中空气冷却器负荷增加4.73%、冷却水量增加1.64%。建议采用二级闪蒸法对换热器中原油汽化问题进行改进,比较了阀门不憋压、阀门憋压和二级闪蒸3种操作工况,结果表明,二级闪蒸法不仅解决了换热器中原油汽化问题,保持了设备操作压力在合理范围内,还可回收更多低温热量,与阀门憋压工况相比,常压加热炉负荷可减少5.30%。The oil vaporization of crude oil in heat exchanger often causes lots of problems. Domestic refineries often use pressure holding valves to build the higher pressure in the heat exchanger before pre-flash column to reduce the rate of oil vaporization, but the higher pressure has certain adverse impact on the efficiency of heat exchange. The simulative analysis was conducted for a heat exchanger with pressure holding valves before pre-flash column of a 12.0 Mt/a crude oil distillation unit by PRO/II software. The results show that with the inlet pressure of heat exchanger rising from 1.2 MPa to 2.2 MPa, the energy recovered from the heat exchanger network reduces by 8.24 % and the subsequent atmospheric furnace load increases by 1.65%, the air cooler load and cooling water are increased by 4.73% and 1.64%, respectively. Two stage pre-flash drums solution is suggested to solve the problem. The results of three cases were compared with or without pressure holding valve and the two pre-flash drums solution. The results indicate that the two stage pre-flash drums solution can not only maintain the operating pressure in a reasonable range, but also recycle more low-temperature heat, and the atmospheric furnace load is reduced by 5.30%.

关 键 词：换热器 原油汽化 阀门憋压 二级闪蒸 

分 类 号：TE965[石油与天然气工程—石油机械设备]