The utility model provides a three-phase multi-stage separator for
petroleum and
natural gas, and belongs to the technical field of three-phase separators. Comprising a shell, a plurality of rectiblocks are arranged in the shell at intervals and divide the shell into a liquid inlet chamber, a layering chamber and a
discharge chamber, the liquid inlet chamber of the shell is connected with an oil inlet
pipe, the
discharge chamber is internally connected with a water outlet
pipe through a water separation
assembly, and the bottom wall of the end, away from the oil inlet
pipe, of the shell in the
discharge chamber is connected with an oil outlet pipe; a gas collecting cylinder with the top connected with a gas outlet pipe is fixedly arranged on the shell and located at the top of the discharge chamber, a
demister is arranged in the gas collecting cylinder, a water retaining cap and a water collecting ring are sequentially arranged in the gas collecting cylinder and located under the
demister, a drainage pipe is connected to the bottom of the water collecting ring, and one end of the drainage pipe extends to the bottom of the shell. Condensation on the
demister can be blocked through the water retaining cap, is guided to the water collecting ring and enters a
water layer at the bottom of the shell through the drainage pipe, so that water drops can be effectively prevented from falling into a
petroleum layer, and the oil-water separation device has the
advantage of improving the oil-water separation effect.