PROCESS FOR RECOVERING OIL AND TREATING RESULTING PRODUCED WATER WITH CERAMIC MEMBRANES

摘要

A method of recovering oil from an oil well includes recovering an oil-water mixture from the oil well and separating produced water from the oil-water mixture. Thereafter, the produced water is directed through a ceramic membrane that removes free oil and emulsified oil from the produced water. The method or process further includes cleaning the ceramic membrane in online and offline modes. In the offline mode, cleaning is achieved by periodically backflushing the ceramic membrane with an aqueous media having a pH of 13 or greater and a temperature of 60°C or greater. Further, the ceramic membrane is cleaned in the offline mode by applying the following operations. In one or more clean-in-place operations, an aqueous alkaline media at a pH of 13 or higher and a temperature of 60°C or higher is directed through the ceramic membrane. In one or more clean-in-place operations, the ceramic membrane is also cleaned with an aqueous acidic media that contains dissolved citric acid. Finally, in one or more clean- in-place operations, a liquid hydrocarbon is directed through the ceramic membrane.