Operating instructions

INTRODUCTION
1-2 15 Apr 11
ACD-1500Degasser
SAFETY
Section 2 of this manual contains relevant safety information relating to both operation and
maintenance of this equipment. Be sure this information is read and understood by all personnel.
DO NOT operate the equipment if defective or faulty mechanical or electrical components are
detected.
EQUIPMENT USE
The degasser and associated components are designed exclusively for releasing entrained gases
from slurries. Derrick Corporation does not authorize any other use of this equipment. Intended
usage of equipment includes compliance with the operating, maintenance, and safety procedures
included in this manual.
DESCRIPTION AND OPERATION
The ACD-1500 degasser (Figure 1-2) is designed to be immersed in a mud tank. The degasser
uses impact/turbulence combined with a large surface area of exposure to liberate gas from the
mud. Entrained gases are removed from drilling fluid by exposing a thin film of the mud to the
atmosphere. Drilling fluid is pumped by the centrifugal pump at the bottom of the degasser up
through the pump riser and delivered to the impact plate, which disperses the liquid horizontally
against the interior surface of the spray tank. The mud spreads evenly across the horizontal
surface of the spray tank, allowing the bubbles to break free from the mud. Degassed mud flows
out the discharge outlet and returns to the tank. Mud is continuously circulated from the tank
through the degasser and back to the tank. This recirculation process maximizes gas removal.
For proper functioning, the fluid level in the mud tank should be higher than the centrifugal pump
bolting flange.
The liberated gas exits the vent flange at the top of the spray tank. The exhaust blower at the top
of the vent assists in drawing gas away. The blower’s discharge flange may be connected to a
pipe flange having an 8-1/2” (215mm) diameter circular 4-hole bolt pattern to transport the gas
away from the degasser.
The ACD-1500 degasser processes up to 1500 gallons per minute (gpm), depending on the
impact plate gap. This adjustable gap may be varied within a range of 1/4” to 1-1/4” (6mm to
32mm) in 1/4” (6mm) increments to control the thickness of the dispersed film. By forcing the mud
through the small gap between impact plate and pump riser, it strikes the walls of the spray tank with
considerable force, producing turbulence that assists in liberating gas from the mud.
Maximum process throughput is achieved with the largest impact plate gap, while flow is
diminished with a smaller gap. Generally, the higher the flow the lower the release of entrained
gas. The impact plate gap is adjusted to meet the mud conditions. High gas content may warrant
a small gap to maximize removal of entrained gas, while a larger gap may be suitable when gas
content is lower and higher flow is desired.