The Different Applications about Mud Gas Separator and Vacuum Degasser Used in Drilling

Aug 30, 2013

Effective solids control can be attributed to the overall performance of all the components of the mud systems. Conditioning the drilling fluids with the goal of dramatically lowering maintenance cost, avoiding excessive chemical treatment and maintaining mud systems volume will decrease the chance of equipment failure, unnecessary high mud costs, hole and drilling problems.

Mud/gas Separator

Mud/gas separator is commonly called a gas-liquid separator or poor boy degasser. It captures and separates large volume of free gas within the drilling fluids. If there is a " kick" situation, this vessel separates the mud and the gas by allowing it to flow over baffle plates. The gas then is forced to flow through a line and vent it to a flare. A " kick" situation happens when the annular hydrostatic pressure in a drilling well temporarily ( and usually relatively suddenly ) falls below that of the formation, or pore, pressure in a permeable section downhole, and before control of the situation is lost.


Mud/Gas Separator
 

The principle behind the mud gas separator is relatively simple. On the figure, the mud and gas mixture is fed at the inlet allowing it to impinge on a series of baffles designed to separate gas and mud. The free gas then is moved into the flare line to reduce the threat of toxic and hazardous gases and the mud then discharges to the shale shaker and to the mud tank.

Vacuum Degasser

A degasser is a device used in drilling to remove gasses from drilling fluid which could otherwise form bubbles.

Vacuum type is the most common form of degasser. It can be horizontal, vertical or round vessel. A vacuum action is created to pull in the gas cut mud. When the liquid enters the mud tank, it will flow and be distributed to a layer of internal baffle plates designed for the mud to flow in thin laminar film and is exposed to a vacuum that forces the gas to escape and break out of the mud. The vacuum pump moves the escaping gas from the vessel discharging it to the rig's flare or environmental control system.


Vacuum Degasser
 

Drilling fluids mud gas separator is the primary degassing equipment for disposing drilling fluids. Compared with vacuum degasser, the major difference is the mud gas separator is mainly used for eliminating the big bubbles whose diameter is larger than 3mm in drilling fluids. In addition, mud/gas separator is mainly by gravity impact action to realize the separation, and yet the vacuum degasser adopts the theory of vacuum, centrifugation.

The handling capacity of vacuum degasser is less than the mud gas separator, but can eliminate gas more thoroughly. Generally the drilling fluids disposed by mud/gas separator still contains minute bubbles, after through shale shaker, and enter into the vacuum degasser to dispose.