Split-flow degasser

An apparatus for degassing drilling fluid, comprising:

• a pressure vessel comprising:
• a top portion;
• and
• a bottom portion;
• a vacuum blower in fluid communication with the pressure vessel;
• a slotted centrifuge tube having a cross-sectional area;
• a motor configured to rotate the slotted centrifuge tube;
• an evacuation pump having an impeller connected with a lower end of the slotted centrifuge tube;
• and
• an outlet conduit connected to the evacuation pump;
• a drilling fluid inlet providing an opening between the bottom portion of the pressure vessel and the outlet conduit;
• an inlet pipe having an internal diameter, the inlet pipe spaced a distance away from the lower end of the slotted centrifuge tube, a region between an upper end of the inlet pipe and the lower end of the slotted centrifuge tube having a circumferential surface area, the circumferential surface area of the region being A2=πDH where D is the internal diameter of the inlet pipe and H is the distance of the inlet pipe away from the lower end of the slotted centrifuge tube;
• a mud tank, the pressure vessel being contained within the mud tank, the mud tank comprising:
• a first reservoir in fluid communication with the inlet pipe;
• and
• a second reservoir in fluid communication with the outlet conduit;
• a threaded fastener connected to the inlet pipe to adjust the distance between the slotted centrifuge tube and the inlet pipe, wherein adjusting the distance adjusts fluid flow, wherein an internal diameter of the inlet pipe is selected according to a ratio between a cross-sectional area of the inlet pipe and the cross-sectional area of the slotted centrifuge tube, and wherein the distance between the upper end of the inlet pipe and the lower end of the slotted centrifuge tube is determined according to a ratio between the circumferential surface area of the region and the cross-sectional area of the slotted centrifuge tube;
• a partition separating the first reservoir and the second reservoir of the mud tank, the partition having a gap therein to allow excess degassed drilling fluid to flow over the partition from the second reservoir to the first reservoir to avoid high pressure;
• and
• a handling bracket attached to the motor allowing the pressure vessel to be lifted out of the mud tank.