Abstract: A selenium-containing aqueous stream may be used as a quenching water stream and optionally a cutting water stream in a delayed coking process to effectuate the removal of selenium from the selenium-containing aqueous stream resulting in the formation of a selenium-coke product. In addition, selenium may be concentrated in selenium-containing stripped sour water streams by recycling the stream in one or more hydroprocessing units and one or more sour water stripper units and subsequently removed by using a portion of the selenium-containing stripped sour water stream as a quenching water stream and optionally a cutting water stream in a delayed coking process.