表面处理：镀锌(蓝锌、黄锌及镀锌上蜡)、镀镍、磷化黑。

Surface processing: plate the zinc (blue zinc, yellow zinc and plate the zinc up the wax) and plate the Ni, point phosphate to turn black.

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该工艺采用焙烧法将污泥中的金属组分同类分离，并结合黄钠铁矾沉淀法去除杂质铁等工艺对铜、镍、铬进行了回收利用。

Different metals are separated from the electroplating sludge by roasting and copper, nickel and chromium were recovered with suitable methods such as removing iron by sodium jarosite precipitation.

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