The core of the DCFCM technology is the integrated technology of axial flow cyclone plus microbubble air flotation and charged membrane filtration. Based on this technology, we have developed a series of integrated oil-water separation equipment, which have been successfully working in oil processing stations, oil drilling platforms, transfer stations, and sewage treatment plants in Sinopec, PetroChina and CNOOC. It has completely solved the old problems from conventional process flow like complex equipment, more land area, messy pipelines, low degree of self-control, and inconvenient operation. It is a new low-cost and efficient process and a method featuring of fast, efficient and digital in oilfield oily waste water treatment.