Key words: oilfield, oil-water mixture, oil dehydration, purification of waste water, chemicals – demulsifiers and flocculants, compositional analysis of impurities in water.
Oil dehydration and purification of waste water in fields at the late development stage are primarily carried out in Free Water Knock Out units with oil-water mixture treatment with demulsifier and natural gravitational settling applied. The required treatment quality of waste water, determined by the design documentation for field production, is not always guaranteed. The performed studies have verified the required quality of oil dehydration and waste water purification can be achieved by sequential treatment of oil-water mixture with such chemicals as demulsifiers and flocculants. The flocculants efficiency depends on the compositional analysis of impurities in the aqueous phase of oil-water mixtures transporting to Free Water Knock Out units.
