池子里满是淤泥和绿色的污水。

The pond was full of mud and green slime.

《牛津词典》

“下水道淤泥”，是指经城市污水处理厂产生的淤渣，包括预处理的废物、污垢和性质不稳定的淤泥。

"Sewage sludge" means sludge arising from urban effluent treatment plant and includes pretreatment waste, scourings and unstabilised sludge.

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饮用水、污水和淤泥处理技术和水系统管理。

Potable Water, Wastewater, and Sludge treatment technology and system management;

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