The Study On Energy Saving And Carbon Emission Reduction Of A Crude Distillation Unit

As the first process in the petroleum processing process,the crude distillation units play a particularly important role.However,at present,the capacity of China’s oil refining industry whose energy efficiency is better than the benchmark level（8.5kgoe/t oil）accounts for only 25%.As a large energy consumption in the refinery,crude distillation units are the important part of supporting the“double carbon”goal.Due to many factors,such as the small scale of a single unit,the low final temperature of heating-exchange network,the imperfection of the heat integration and so on,the energy-saving transformation of crude distillation units are not in place,and there are still a lot of energy-saving space.This paper takes a 530×10⁴ t/a crude distillation unit as the research object,which is a typical process flow of three towers and two boilers.Using Aspen Hysys to establishe the steady-state model,this paper carries out the process index analysis,material balance analysis,energy consumption analysis,thermodynamic analysis,carbon emission analysis,heating-exchange network analysis,etc.The comprehensive analysis shows that the current energy consumption of the unit is 10.64kgoe/t oil,and the carbon emission of this process is 159849 t CO₂/a.Then,using the six-level concept of energy-saving optimization,this paper analyzes the energy consumption of the whole process,and combs out 10 energy-saving optimization measures in combination with carbon emission reduction and economic factors,mainly including equipment unit optimization,process and heating-exchange network optimization,low-temperature heat recovery,heat combination between units,circulating water system optimization,steam system optimization,etc.Through comprehensive energy-saving optimization,it estimated that the energy consumption can reduced by 3.44kgoe/t oil and the overall energy consumption can be reduced to 7.2 kgoe/t oil.At the same time,65291t CO₂/a carbon reduction and 6941×10⁴RMB/a economic benefits can be achieved in the whole process.