Principle, structure and types of oil-gas separator

Oil gas separator is a device that separates the crude oil produced by the oil well from the associated natural gas. The oil-gas separator is placed between the submersible centrifugal pump and the protector to separate the free gas in the well fluid from the well fluid. The liquid is sent to the submersible centrifugal pump, and the gas is released to the annular space of the tubing and casing. In this article, the quick screen editor introduces its principle, structure and types. Let’s learn about it!

Principle of oil-gas separator:

The oil-gas separation element is the key component to determine the compressed air quality of the air compressor. The high-quality oil-gas separation element can not only ensure the high efficiency of the compressor, but also the service life of the filter element can reach thousands of hours. The compressed air from the compressor head carries large and small oil droplets. Large oil droplets are easy to be separated when passing through the oil-gas separation tank, while small oil droplets (suspended oil particles with a diameter of less than 1um) must be filtered through the micron and glass fiber filter layer of the oil-gas separation filter element. Some particles are directly intercepted by the filter material through the diffusion effect of the filter material and the inertial collision condensation energy mechanism, so that the suspended oil particles in the compressed air will quickly condense into large oil droplets. Under the action of gravity, the oil will gather at the bottom of the oil core and return to the lubricating oil system of the machine head through the inlet of the oil return pipe at the bottom recess, so that the compressor can discharge more pure and oil-free compressed air. The solid particles in the compressed air stay in the filter layer when passing through the oil core, which causes the pressure difference (resistance) of the oil core to increase continuously. As the service time of the oil separator increases, when the pressure difference of the oil separator reaches 0.08 to 0.1MPa, the filter element must be replaced, otherwise the operating cost of the compressor will be increased.

Structural composition of oil-gas separator:

1. Separation part: it is divided into three steps. The primary separation part mainly divides the oil-gas mixture into gas and liquid. The main separation part is to use the sedimentation separation principle to separate the droplets with a diameter greater than 100um from the gas to a large extent. In the mist removal and separation part, oil droplets with a diameter of more than 10 ~ 30um are removed by the collision principle.

2. Pressure control part: the internal pressure is controlled by self operated pressure regulating valve.

3. Liquid level control part: use float ball liquid level control valve to control the liquid level height.

4. Heating part: the oil and gas in the liquid containing part of the separator can be fully and naturally separated, and the high pour point crude oil will not freeze when the separator is shut down.

Type of oil-gas separator:

1. Gravity separation type: horizontal and vertical gravity separators are commonly used;

2. Collision coalescence type: screen coalescence and corrugated plate coalescence separator;

3. Cyclone separation type: reverse flow, axial flow cyclone separator, compact gas-liquid separator;

4. Rotary expansion type: heat transfer oil must be injected into the system from the expansion tank through the oil-gas separator.