The effect of ferrous sulfate as a coagulant
Thread Content
Ferrous sulfate heptahydrate was used in coagulation experiments, with dry addition; the pH was adjusted to 9-10 in advance. After addition, stirring caused the water to turn yellow, and precipitation occurred after two hours. The COD level remained essentially unchanged, with some cases even showing an increase. I wonder how common the practical use of ferrous sulfate is in engineering applications?
Ferrous ions are generally used as reducing agents and rarely as coagulants, as the oxidation of excess ferrous ions also increases COD
I adjusted this, and it seems that when the pH is between 9 and 10, the flocculation effect isn’t very good
Generally, when dealing with printing and dyeing wastewater, adding acidic ferrous sulfate agents to a neutral solution and then adjusting the pH to a slightly alkaline level yields good results!
Ferrous sulfate is generally used as a reducing agent. When used as a coagulant, consideration should be given to the amount of ferrous sulfate added; excessive iron ions can actually affect water quality and lead to an increase in COD.