A degasser is a device used in drilling to remove gasses from drilling fluid which could otherwise form bubbles.
Degassers are designed to remove virtually all entrained gases from drilling mud, including H2S and corrosive oxygen.
Degassers tend to be of two types: vacuum and centrifugal.
1. Vacuum degassers are more efficient degassers, but have lower throughput capability. They are better suited to lower flow rate mud systems with high gas cuts or systems that are very sensitive to entrained gas. Vacuum degassers require a separate mud pump to operate the eductor nozzle, which can drive up the initial cost of installation.
2. Centrifugal degassers employ centrifugal forces to separate the gas from the fluid by exerting centrifugal force to the mud, multiplying the force acting on the gas bubbles to increase buoyancy and release. The increase in buoyancy accelerates the bubble-rise velocity. As the bubbles rise toward the surface, they escape the mud and are further broken down by flow turbulence. A light vacuum is pulled by a regenerative blower to vent the gas. The freed gas and the gas-free mud are then separately discharged as desired
