Composite oil-water separation device

The utility model relates to the technical field of oil-water treatment, in particular to a composite oil-water separation device, which can get rid of limitation caused by different oil concentration and comprises an oil-water separator, an overflow weir plate is arranged at the bottom inside the oil-water separator, and a separation cavity is arranged inside the oil-water separator and on one side of the overflow weir plate close to an inlet pipe. An overflow cavity is arranged in the oil-water separator and on the side, away from the inlet pipe, of the overflow weir plate; a separation barrel is arranged in the middle of the interior of the separation cavity; an oil discharge pipe is arranged at the bottom end of the separation barrel; a water discharge pipe is arranged at the bottom end of the overflow cavity; a first liquid level control valve and a second valve are sequentially arranged on the drainage pipe from the head to the tail, a second liquid level control valve is arranged on the oil drainage pi