Abstract: The oily wastewater in a natural-gas processing plant mainly comes from natural gas dewatering,pigging effluent and bottom water of storage tanks. The main pollution factors are petroleum and organic pollutants. The amount of oily wastewater produced is about 30 m³ per day,oil in water is flammable and volatile condensate light oil,the oil content in water is affected by many factors,such as liquid coming from sea pipe,fluctuation of upstream and downstream flow,etc,the oil content fluctuates randomly from 0 to 100%,the existing device has a large oil-water separation load,and the treatment effect is not up to the standard. After adopting the integrated skid-mounted oil-water purification and separation equipment on site,the oily wastewater treatment effect is good and meets the design requirements. It is of great significance to the stable operation of the natural-gas processing plant,upstream and downstream production processes,and also provides reference for the process modification work under similar working conditions.

Key words: integration, oil-water purification, process modification