In the oilfield, the mud gas separator is sometimes known as ‘poor boy degasser’ or ‘gas buster’. They may be vertical or horizontal in design.
A Vertical separator is normally used for high fluid throughput, while a horizontal separator provides a longer retention time and superior gas separating capacity. Internal design and configuration (e.g. blast chamber, baffle plate etc.) governs the individual efficiency of the equipment.
The limitation to the efficiency of a mud gas separator is dedicated by
1. Separating Capacity – the capacity to separate gas from the liquid is determined by the internal configuration and fluid dynamic characteristics of the separator.
2. Venting Capacity – the capacity to vent gas through the derrick vent is subject to the backpressure of the vent line and the hydrostatic head of the liquid seal.
3 Liquid re-entrainment Capacity – the capacity when the liquid droplets break away from a gas/liquid interface to become suspended in the gas phase. The term re-entrainment is used in separator design because it is assumed that droplets have settled to the liquid phase and are then returned to the gas phase.
It should be noted that the capacity of the separator to separate gas from the liquid may be considerably less than the capacity to vent gas within the limit of the liquid seal.