Abstract
With an ever increasing pressure on drilling performance and economics, the use of invert emulsion fluids has continued to be a necessity. Increased environmental responsibility has brought with it an increase in the cost and liability associated with responsible disposal of contaminated drill cuttings. In environmentally sensitive areas, it is unlikely that any discharges of contaminated cuttings will be permitted. Subsurface injection cannot be used as a solution in all cases, so other treatment methods must be found to minimize future environmental liability.
Developing invert emulsion drilling fluids designed to meet the demands of high-performance drilling and have chemical characteristics that can be used to optimize contaminated cuttings treatment has been key in minimizing environmental impact. Developing efficient treatment techniques tailored to the local environment has been equally important. The environmental responsibility picture has been completed by combining the chemistry and treatments to produce an end product that can be beneficially re-used in the local environment.
The authors will discuss the design changes in drilling fluid chemistry and show the field performance of these fluids. The associated treatment techniques that can be applied will also be reviewed, along with the local environmental climate required to ensure successful application of such treatments. The authors also will review the potential for beneficial reuse of contaminated cuttings in this context and show field trial results.
