糠醛精制装置用能存在的问题及优化

Problems in Energy Use of Furfural Refining Unit and Optimization Measures

荆门石化糠醛精制装置分轻、重两套,采用"两头一尾"的生产工艺,2007年进行流程优化和改进后,两套装置综合能耗降至26.04kg标油/t,但仍偏高。对其能耗结构进行分析后,发现装置存在抽出液溶剂回收系统一次蒸发率不到30%,大量的糠醛溶剂需要通过加热炉加热从二次塔蒸出;重套装置2台加热炉加热效率不到80%;装置1.0MP蒸汽用量大,自产蒸汽和低温余热没有充分利用;循环水利用不充分;部分电机机组效率偏低等问题。通过提高抽出液溶剂回收系统一次蒸发率、对重套糠醛精制装置加热炉进行节能改造、减少1.0MPa蒸汽和自产蒸汽用量、冷却器循环水串级使用、电机安装变频调速器和切削叶轮等一系列节能技术措施的实施,2009年1～5月,轻、重两套糠醛精制装置综合能耗降至17.27kg标油/t,同比2007年下降了33.68%,达到中国石化系统同类装置先进行列。

SINOPEC Jingmen Company has two furfural refining units （one light-duty and one heavy-duty） using two-refining-unit-and-one-tail-gas-device technology.After a process upgrade and improvement in 2007,the overall energy consumption of the two units dropped to 26.04kg of oil equivalent per ton of feedstock,which was still high.Analysis of energy consumption of the units reveals many problems.The one-step evaporation rate of the extraction liquid solvent recycle system was less than 30% and a large amount of furfural solvent needed to be distilled from the secondary tower after being heated in the heating furnaces; The heating efficiency of the two heating furnaces of the heavy-duty furfural refining unit was less than 80% ;The units＇ 1.0MPa steam consumption is high and the steam produced by the units themselves and low-temperature residual heat were not fully utilized ;the circulating water was not fully utilized;the efficiency of some motors was excessively low.To resolve these problems,Jingmen Petrochemical Company took a series of energy saving measures including raising the one-step evaporation rate of the extraction liquid solvent recovery system,enhancing the energy efficiency of the heating furnaces of the heavy-duty furfural refining unit,reducing the consumption of 1.0MPa steam and the steam produced by the unit itself,introducing cascade use of the circulating water of the cooler and installing inverter speed regulators and cutting impellers for motors.From January to May 2009,the overall energy consumption of the light and heavy-duty furfural refining units dropped to 17.27kg of oil equivalent per ton of feedstock,down 33.68% from 2007.These units are now among the most energy