The invention discloses an oil-water
separation method and an oil-water separation device. The device consists of a primary oil-water separation unit, an adsorption and
desorption unit, an advanced oil-water separation unit and a drainage unit, wherein a
breather pipe is arranged at the top end of the primary oil-water separation unit and communicated with the
atmosphere, and a transverse communicating hole is formed in the upper part of a partition between the adjacent units; a coarse grid residue basket in the primary oil-water separation unit is communicated with a fine grid residue basket by virtue of a diversion opening, and both the coarse grid residue basket and the fine grid residue basket are turnover and removable; an oil
discharge mechanism consisting of a floating ball accommodating cavity, a floating ball and a plugging cylinder is connected with an oil
discharge pipe; an adsorption and
desorption packing layer is arranged in the adsorption and
desorption unit; the advanced oil-water separation unit is provided with the oil
discharge mechanism; the drainage unit is provided with a drainage
pipe. The method and the device can be used for continuous, automatic and efficient oil-water separation without manual operation and
energy consumption, and can be used for clearing
sludge without
power equipment, so that the energy is effectively saved; water can be prevented from entering the oil discharge pipe at a peak drainage period, so that the oil-water separation is more thorough.