In nonwoven spunlace production, bacterium breed causes bacterium stickiness to recycling water and blocks core of filtration. These will cause quality problems to the products.

水刺非织造布生产过程中，由于细菌繁殖引起循环水产生细菌粘泥，堵塞过滤芯，导致产品出现质量问题。

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And maybe after only one filtration you will get 'safe' water.

CNN: Nanotech and 'tea bag' to clean up drinking water