This paper analyzed the revamping of ethylene plants in YAN-SHAN Petro-chemical Inc. and that abroad, the economic scale and the ways of re-vamping in ethylene plant are also discussed.

本文分析了国外以及燕山石化公司乙烯装置的技术改造，论述了乙烯装置改造的经济规模及其途径。

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Flowers are so weak, and then the United States and re-yan, still can not afford to North Korea to wind Hanyu night.

花是如此柔弱，再美再艳，依然经不起朝来寒雨晚来风。

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