BAKER HUGHES - Drilling Fluids Reference Manual

FLUIDS ENVIRONMENTAL SERVICES
Thermal Treatment
There are several methods of thermal treatment (desorption) of drilling waste, the most common
being indirect thermal desorption:
The externally heated rotary dryer is sealed on either end to limit oxygen entering the system, and
vapor exiting. The dryer shell heats cuttings to between 600 and 900°F by conductive heat transfer.
Retention time within the drum varies between 20 and 30 min. to thoroughly heat and vaporize all of
the liquids. Cleaned cuttings exit as dry, inert dust, and are re-hydrated with water to a manageable
consistency prior to non-hazardous disposal or use in construction materials, e.g., bricks, road base or
cover for a sanitary landfill.
The hot oil and water vapors are filtered through a high-temperature, fabric-filter bag-house for fine
particulate removal, and subsequently condensed into liquid by means of a shell and tube condenser
system cooled by a closed-loop cooling tower. The fluid then passes through an oil / water separator
system, with recovered water used as makeup water for the cooling tower and cuttings re-hydration,
and recovered oil returned to the client for reuse in the mud system (or other use), with a small
portion used to fuel the self-contained, thermal-desorption process.
Air emissions from the system are well below EPA's 1990 Clean Air Act for Particulate Matter, SOx,
NOx and VOCs, and EPA has designated this type of system as "BDAT" (Best Demonstrated
Available Technology) for cleanup
of hydrocarbon-contaminated soils.
BAKER HUGHES DRILLING FLUIDS
REFERENCE MANUAL
REVISION 2006 14-28