Dissolved Oil Removal from Ethylene Plants Quench Water

A method for removing dissolved hydrocarbons from water may comprise: cracking a mixed hydrocarbon stream in a cracking furnace to produce a cracked gas effluent; quenching the cracked gas effluent in a quench water tower with quench water to produce a quenched gas stream and a spent quench water stream comprising water, tars, heavy aromatic hydrocarbons, gasoline, dissolved oil, and dispersed oil; feeding the spent quench water stream to a liquid-liquid extraction unit wherein the liquid-liquid extraction unit removes at least a portion of the dissolved oil and produce an extracted effluent stream.