Abstract: At present, the price of light raw materials in the chemical raw material market remains high, and each ethylene plant has to face the situation of heavy cracking raw materials. The cracked gas produced by the cracking of heavy raw materials contains more gasoline components, and some of them enter the cracked gas compressor, causing the compressor to operate beyond the original design load. This greatly increases the burden on the compressor to drive the steam turbine. In order to maintain the high-load operation of the device, it is necessary to improve the capacity of the compressor in operation to drive the steam turbine. After comprehensive analysis, it is possible to improve the capacity of the compressor in operation to drive the steam turbine by improving the steam quality without replacing the main components of the steam turbine unit.

Key words: steam turbine, compressor, insulation material, ultrahigh pressure steam, heavy feedstock