Intensified flotation of finely emulsified oils from effluents

Small additions (1 to 5 mg/l) of cationic surfactants make it much easier to remove finely emulsified oil droplets from coking-plant effluents by flotation. The residual oils concentrations can be reduced to 10 to 30 mg/l by flotation with surfactants. Their effectiveness is highly specific and varies with the nature of the surfactant and the oils, and also with the composition and pH of the effluent.