乙烯装置增设甲烷氢压缩机节能效果评价  

Energy-saving effect on adding methane hydrogen compressor in ethylene unit

作　　者：雷伟伟[1] 刘正明[1] 史云伟 徐沛[1] 殷新[1] LEI Weiwei;LIU Zhengming;SHI Yunwei;XU Pei;YIN Xin(Sichuan Petrochemical Co.,Ltd.,CNPC)

机构地区：[1]四川石化有限责任公司

出　　处：《石油石化节能》2022年第11期53-58,73,共7页Energy Conservation in Petroleum & PetroChemical Industry

摘　　要：四川石化乙烯装置原料与设计偏差较大,导致产出的副产品中甲烷氢收率达到18%以上,严重制约了乙烯装置负荷的提升。这部分甲烷氢在分离冷区2#氢气分离罐中,-162℃、3.4 MPa(A)条件下与氢气进行分离,经节流阀节流并回收冷量后返回裂解气压缩机一段吸入罐。这部分甲烷氢经裂解气压缩机加压后持续在系统中循环,长期累积后,导致分离系统出现多处瓶颈,冷分系统甲烷长期处于超负荷状态,对装置安全平稳运行造成隐患,且由于系统内循环甲烷量的增加,装置能耗明显上升。增设了1台螺杆压缩机,乙烯装置负荷由原295 t/h可提高至310 t/h,每年可增产乙烯3.45×10^(4) t;同时,节省了火炬头消烟蒸汽用量;裂解气压缩机段间循环量减少,驱动蒸气消耗量降低,每小时可多抽高压蒸汽7 t左右。The feedstock of ethylene unit deviates greatly from the design,resulting in the production of up to 18%methane hydrogen in the produced byproducts,which seriously restricts the increase of ethylene unit load.What's more,this part of methane hydrogen is separated from hydrogen in the 2#hydrogen separation tank in the separation cold area at-162℃and 3.4 MPa(A).After throttling by the throttle valve and recovering the cold capacity,it returns to the first stage suction tank of the cracking gas compressor.Then this part of methane hydrogen continues to circulate in the system after being pressurized by the cracking gas compressor.After long-term accumulation,many bottlenecks appear in the separation system.In addition,the methane in the cold separation system has been overloaded for a long time,causing hidden dangers to the safe and stable operation of the unit,and the energy consumption has increased significantly due to the increase in circulating methane.In particular,after adding a screw compressor,the load of ethylene unit can be increased from 295 t/h to 310 t/h and the annual output of ethylene can be increased by 34500 tons,which saves the amount of smoke elimination steam at the flare head.The circulation is reduced between sections of the cracking gas compressor,and the consumption of driving steam is reduced,which can be pumped about 7 tons of highpressure steam per hour.

关 键 词：乙烯装置 分离系统 螺杆压缩机 能耗 甲烷氢 

分 类 号：TQ221.211[化学工程—有机化工]