Abstract: The energy consumption status of a 1 Mt/a ethylene plant and the energy-saving measures that have been taken are introduced. Six energy-saving optimization measures have been adopted, including the application of a new energy-saving and viscosity-reducing technology for quench oil, the addition of a heat exchange process for process condensate and desalinated water, the modification of the demethanizer overhead process to a vertical CIV condenser form, the waste heat utilization of boiler continuous blowdown, the conversion of the ethylene machine turbine from extraction-condensing type to backpressure type, and the collaborative optimization of electrification. These measures can reduce the energy consumption of the plant by 1734.28 MJ/t in total, and the energy-saving effect is remarkable. Combined with the actual situation of the plant, six next-step energy-saving optimization suggestions are put forward, including achieving the theoretical ratio combustion of the cracking furnace, adding a secondary air preheater to the cracking furnace, installing frequency converters for high-power pumps, carrying out temperature and pressure reduction operations for the debutanizer tower, and applying full-process intelligent control technology at an appropriate opportunity. This has good guiding and reference significance for the energy-saving and consumption reduction work of similar plants.

Key words: ethylene, cracking furnace, separation technology, energy consumption, optimization measures, economic benefits