洛阳石化延迟焦化装置节能分析

Analysis of Potential for Saving Energy for Delayed Coking Unit in Sinopec Luoyang Co.

洛阳石化140×104t/a延迟焦化装置采用"一炉两塔"和"可灵活调节循环比"的工艺流程,2008年和2009年装置综合能耗分别为35.42kg标油/t和33.36kg标油/t,与设计值、中国石化平均水平(24.27kg标油/t)相比差距较大。综合分析,能耗较高的原因包括蜡油汽包产0.4MPa蒸汽未计入能耗、1.0MPa蒸汽放空、低温热回收系统未投用、蜡油热输出量小、装置加工负荷率低以及加热炉效率低等。为此,对装置采取用0.4MPa蒸汽替代1.0MPa蒸汽;回收分馏塔顶油气、接触冷却塔顶油气和冷焦水低温热量;增加稳定汽油热出料流程;增设节电变频设施,减少电耗;降低加热炉排烟温度和炉外壁温度;加热炉进料泵叶轮抽级或更换为小叶轮,降压节能;增上加热炉先进控制(APC)手段,保证加热炉最佳燃烧;加热炉出口管线保温及管托更新换型,增加空气预热器等措施,有效降低装置能耗。

Sinopec Luoyang Company＇s 140xl04t/a delayed coking unit uses a process characterized by ＂onefurnace-two-towers＂ and ＂flexibly adjustable circulation ratio.The overall energy consumption of the unit was 35.42kg of oil equivalent per ton in 2008 and 33.36kg of oil equivalent per ton in 2009.There was a big gap between the level of energy consumption of this unit and the designed value for the unit and Sinopec＇s average energy consumption level （24.27kg of oil equivalent per ton）.Comprehensive analysis suggests that the main causes of high energy consumption by the unit include： the 0.4MPa steam produced by the wax oil steam drum was not included in calculating energy consumption; 1.0MPa steam was vented as waste;no lowtemperature heat recovering system is in place;the heat output from wax oil is too small;the unit＇s working rate is low;the efficiency of the heating furnace is too low.Countermeasures include replacing the 1.0MPa steam with 0.4MPa steam;recovering the oil and gas at the top of the distillation tower and the cooling tower as well as the low-temperature heat in coke cooling water;adding a process to stabilize hot gasoline discharges;adding power-efficient frequency regulating devices to reduce power consumption;reducing the funnel temperature for the heating furnace and the temperature for the outer wall of the furnace ;extracting impeller stages or substituting smaller impellers for the feeding pump of the heating furnace to reduce pressure and save energy;adding Advanced Process Control （APC） for the heating furnace to ensure an optimum combustion in the heating furnace ;taking thermal insulation measures for the outlet pipelines of the heating furnace and replacing or upgrading pipeline brackets and adding air preheaters to effectively reduce the energy consumption of the unit.