REMOVING HEAVY METALS IN A BALLASTED PROCESS

A system for treating metal-contaminated wastewater includes a primary treatment sub-system, a secondary treatment sub-system, and a tertiary treatment sub-system. The tertiary treatment sub-system includes a reactor tank, a source of ballast material, a source of coagulant, a solids-liquid separator, and a controller configured to recycle ballasted solids from the solids-liquid separator to the reactor tank an amount sufficient to generate metal hydroxide floe in the reactor tank to reduce a concentration of dissolved metal in the reactor tank. 种用于处理金属污染的废水的系统包括级处理子系统、二级处理子系统和三级处理子系统。三级处理子系统包括反应器罐、压载物材料的源、凝结剂的源、固体-液体分离器和控制器，所述控制器被配置成将压载固体从固体-液体分离器再循环至反应器罐，所述压载固体的量足以在反应器罐中产生金属氢氧化物絮凝物以减小反应器罐中溶解的金属的浓度。