台灣在2025年即將面臨非核家園的政策實現，然而，核電廠除役並非是一件簡單的任務，依法規台電公司規劃的時程最長於二十年內完成，包含(1)除役過渡階段、(2)除役拆廠階段、(3)廠址最終狀態偵測階段與(4)廠址復原階段。

對電廠的廢棄金屬進行除污作業，包含了電化學除污、化學除污、生物除污、機械除污等方法，其中，電化學除污的好處是其消耗的化學品較少，可以深入管材的轉彎處，且消耗較化學除污少的化學品，速度也較單純浸泡式的化學除污快，在實際應用上非常有潛力。故本文的重點在於，在實驗室的小規模測試下，測量電化學除污的速率，與問題的提前發現。

本文的測試材料為碳鋼，在反應器機組中是常見的材料，值得一提的是，在放大試片的4cm*4cm實驗中，我們沒有觀察到明顯的不均勻問題，得到與小規模測試的2cm*2cm試片相近的除污效果。

最後，從除污後表面的SEM（掃描電子顯微鏡）圖像可以分析出，60w%磷酸電拋光後的表面比40w%磷酸電拋光後的表面具有更多的信息熵，也就是，60w%表面粗糙度更高，並且利用多元線性回歸和機器學習給出預測函數、CNN分類器。

In 2025, Taiwan is about to face the realization of the policy of non-nuclear homeland. However, the decommissioning of nuclear power plants is not an easy task. The timetable of Taiwan power company’s planning is as long as 20 years, including four stages: decommissioning transition stage, decommissioning demolition stage, field final state detection stage, and field recovery stage.

The decontamination of waste metals in power plants includes 4 methods: mechanical decontamination, biological decontamination, chemical decontamination, and electrochemical decontamination. Among them, electrochemical decontamination has the benefits of consume less chemicals, can penetrate deep into the turning of the pipe, and consume less chemicals than chemical decontamination, and the speed is faster than simple immersion chemical decontamination. It has great potential in practical application. Therefore, the focus of this article lies in the measurement of the rate of electrochemical decontamination and the early detection of problems under small-scale tests in the laboratory.

The test material in this paper is carbon steel, which is a common material in reactor units. It is worth mention that the uneven problem is not observed in the experiment of enlarging the test piece to 4cm*4cm and the decontamination rate measured is close to that of the 2cm*2cm small-scale test can be obtained.

Finally, from the SEM (Scanning Electron Microscope) image of the surface after decontamination, it can be analyzed that surface after 60 weight percent phosphoric acid electropolishing contains more information entropy than surface after 40 weight percent phosphoric acid electropolishing. Namely, 60 is rougher than 40. MLR and CNN is also used.

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