Ferric Sulfate 1.Color: Yellow or brown 2.Form: Solution or powder ... and cheap cost;(3) has stronger effect to remove COD at the slightly acid condition;(4) specially effective to ... time(10-15min), you can see lots of deposit, there are clear interface in waterstir: first: 150r/min in 6min, ... similar with water making factory. To such water with high color, COD and high BOD, you can use some aids.7, ...