漆膜倾向指数在抗燃油劣化原因分析中的应用

某大型电厂5号机组抗燃油发生劣化,闪点、体积电阻率、泡沫特性超标。为找出劣化原因,按DL/T571-2014《电厂用磷酸酯抗燃油运行维护导则》,对该机组运行抗燃油(运行油)和库存新抗燃油(新油)进行了各项指标测试,结果显示运行油中氯、多种元素和矿物油含量等并无异常,因而难以判断劣化原因。后将漆膜倾向指数运用于抗燃油的劣化原因分析,发现该机组运行油的漆膜倾向指数为43.4,而库存新油的漆膜倾向指数仅为0.1;结合油的颜色变化,说明油品严重老化、急需处理,随即提出换油和加强抗燃油日常监督的建议。由此可见,漆膜倾向指数在油品分析中有重要作用。

Application of Varnish Potential Rating on Deterioration Analysis of Phosphates Ester Fire Resistant Oil

The flash point, volume resistivity and foaming properties of phosphates ester fire resistant oil of unit 5 of a large power plant were found exceeding the standards. To find out the cause of deterioration, many indicators of operating phosphates ester fire resistant oil (operating oil) and new phosphates ester fire resistant oil of unit5 were tested according to DL/T 571-2014 "Guide for operation and maintenance of phosphates ester fire-resistant fluid used in power plant". The results indicated that there was nothing abnormal detected in the chlorine content, elemental analysis or mineral oil, which made it difficult to identify the real cause of deterioration. Then after the varnish potential rating was innovatively applied to the cause analysis of deterioration of phosphates ester fire resistant oil, it was noticed that the varnish potential rating of fire resistant oil of unit 5 was 43.4, while the varnish potential rating of new oil of unit 5 was 0.1. By taking account of the oil color change, it was concluded that the aging of oil was serious and urgent treatment was needed. As a result suggestions to change the oil and strengthen the daily supervision of fire-resistant oil were proposed. Therefore it is of great importance to apply the varnish potential ratings in oil analysis.