蜡油加氢装置换热网络分析与优化

洛阳石化蜡油加氢装置由反应、分馏、富氢气体脱硫、热回收和产汽系统以及装置公用工程部分等组成,设计年加工能力220×104t/a,以减压蜡油、焦化蜡油和脱沥青混合油为原料,采用抚顺石油化工研究院开发的FFHT蜡油加氢处理工艺技术,催化剂采用FF-18型,主要生产低硫含量的精制蜡油,同时副产少量石脑油和柴油,富氢气体经脱硫后送至制氢装置作原料.利用换热网络优化软件PINCH2.0,对蜡油加氢装置换热网络进行模拟,得出现行工艺条件下换热网络最小冷却公用工程和最小加热公用工程用量,提出以现行换热网络的操作工艺为基础,停运分馏塔进料加热炉,提高反应进料加热炉热负荷,在不增加装置换热网络换热器换热面积前提下,充分利用装置现有换热器换热面积余量,增大换热器的换热负荷.实施换热网络优化方案后,降低蜡油加氢装置耗能105.5kg标油/h,年运行时间以8400h计算,年实现节能886.2t标油,标油价格按照3600元/t计算,年实现经济效益319万元；装置进料量按照295t/h计算,则降低装置综合能耗0.358kg标油/t原料.

Analysis and Optimization of Heat Exchanger Network of Wax Oil Hydrogenation Unit

Sinopec Luoyang Company′s wax oil hydrogenation unit consists of reaction,fractionation,hydrogen-rich gas desulfurization,heat recovery and steam production systems and supportive public utilities,with an annual processing capacity of 220×104t/a.The unit uses vacuum wax oil,coker gas oil and asphalt-free mixed oil as feedstock and adopts the FFHT wax oil hydrotreating technology developed by the Fushun Research Institute of Petrochemical Processing.The catalyst used is FF-18.The unit primarily produces low-sulfur fine wax oil and also produces a small amount of naphtha and diesel fuel as byproducts.Hydrogen-rich gas is sent to hydrogen production units as feedstock after the sulfur in it is removed.Researchers simulated the heat exchanger network of the wax oil hydrogenation unit with the help of the heat exchanger network optimization software PINCH2.0 and calculated the minimum demand from the heat exchanger network for heating and cooling public utilities under the current process conditions.They proposed a series of measures to optimize the heat exchanger network based on the current process conditions,including stopping operation of the feedstock heating furnace of the fractionation column,raising the heat load of the reactor feed heating furnace and increasing the heat exchange load of heat exchangers by making full use of the surplus heat exchange area of existing heat exchangers while no additional heat exchange area of heat exchangers of the heat exchanger network is added.After the optimization of the heat exchanger network,the energy consumption of the wax oil hydrogenation unit dropped by 105.5kg of oil equivalent per hour.Assuming the unit operates 8400 hours per year,annual energy savings will reach 886.2 tons of oil equivalent.If the oil equivalent price is 3600 yuan per ton,annual economic benefits from the energy saving reach 3.19 million yuan.If feedstock is fed to the unit at a rate of 295 tons per hour,the overall energy consumption of the unit drops by 0.358kg of oil equivalent per ton of feedstock.