Rectisol process plays an important role in many large-scale chemical projects,which absorption and desorption are physical processes, and is an effective and economic gas purification process. The rectisol process system is huge, the process flow is complex, and the start-up preparation flow is long. By studying the process principle and start-up process, the use time and consumption of public materials in the start-up process of low-temperature methanol washing process are, optimized the consumption of water, steam, nitrogen, etc is greatly reduced, and the purpose of energy saving and consumption reduction can beachieved .