Abstract: As the energy and environment problems are getting intense，it is important to make full use of renewable energy and industrial waste heat. This paper presented a project aiming at recycle and reuses the disposal waste heat in the chemical sector of distillation process. The low-temperature cogeneration technology was utilized to replace the cooling unit of the original system and recover the low-temperature stream waste heat generated in distillation column. The operational conditions at different temperatures were discussed and analyzed. The energy-saving benefit of the waste heat generated in the ethanol - isopropanol distillation process was also considered. The results showed that theoretical generation efficiency and actual generation efficiency were 8.7% and 2.5%，respectively under the most unfavorable conditions in summer (the condensing temperature is 37.5 ℃），and the values were 11.3% and 5.5%，respectively under the most favorable conditions in winter (the condensing temperature is 20.9 ℃）. The annual average theoretical generation efficiency was 10.2%，the actual value was about 4.2%.

Key words: industrial waste heat, low-temperature cogeneration, energy-saving technology of waste heat

摘要： 面对日趋紧张的能源和环境问题，充分开发利用可再生能源及工业余热成为缓解能源危机的重要途径。本文针对化工领域精馏过程中排放的大量余热问题，设计低温发电系统接入原精馏设备中以替代原系统中的冷凝器，利用精馏塔中产品的蒸气热实施发电试验。文中还以此技术的全年运行分析，确定了乙醇-异丙醇化工精馏工艺排放余热的节能效益，表明在夏季最不利工况（冷凝温度为37.5 ℃）下运行时，理论发电效率约为8.7%，实际发电效率约为2.5%；在冬季最有利条件（冷凝温度为20.9 ℃）下运行时，理论发电效率约为11.3%，实际发电效率约为5.5%；年均理论发电效率约为10.2%，实际发电效率约为4.2%。

关键词: 工业余热, 低温发电, 余热节能技术