A mud/gas separator (poor boy degasser) sizing worksheet will assist drilling personnel with the sizing calculations. The worksheet provides a quick and easy evaluation of most mud/gas separators for a specific well application. A brief discussion of other mud/gas separator considerations is provided, including separator components, testing, materials, and oil-based-mud considerations. This paper reviews and analyzes existing mud/gas separator technology and recommends separator configuration, components, design considerations, and a sizing procedure. A simple method of evaluating mud/gas separation within the separator vessel has been developed as a basis for the sizing procedure.


Vaccum Degasser Design Solves Mud Gas Separation Problems

Vaccum Degasser Design Concept Formulation

The new Vaccum Degasser design was formulated from basic principles used in the chemical processing industry. Standard chemical engineering principles that apply to the design of packed towers were the basis for this new design. These principles deal with efficient phase disengagement to provide’ effective gas absorption or gas strip-ping. Specifically, in the top inlet section of a typical packed tower, the overriding operating principles are effective gas/liquid phase disengagement and uniform inlet liquid distribution over the entire tower cross-sectional area.

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The great majority of centrifuges used in drilling are decanting devices, as described previously. The rotary mud separator (RMS), also known as a perforated rotor centrifugal separator, was developed by Mobil in the 1960s. Although it is not, strictly speaking, a centrifuge because the outer barrel is not rotated, it serves the same function that decanting centrifuges do with weighted drilling fluids by discarding ultra-fine and colloidal solids while salvaging silt-size barite, and is often spoken of as another type of centrifuge. Continue reading “ROTARY MUD SEPARATOR”

Pressurized, or Closed, Separators

 Modified Production Separators

The major advantages of a closed pressurized separators are that it
(1) controls gas from the well and sends it to a flare line under pressure and (2) is serviced by a special crew.

The separator is usually operated under 3 to 5 atmospheres of pressure
(45 to 75 psig). Horizontal units are typically about 9 feet in diameter
and 50 feet long, with a throughput of 5 MMcf or 500 bbl fluid. These are
typical numbers, and sizes and pressure vary according to special jobs.

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