A field application of the economic and performance analysis model for a closed-loop system implementation. A district had realized substantial benefits through more effective solids control in earlier years and was interested in 1986 in analyzing the economics of further improvements in solids control. The economic and performance analysis programs were run to predict the costs, potential savings, and recommend a suitable solids control system. It was a nine-well (2-vertical and 7-directional, 4300 ft average depth) infill drilling program within the city limits, which imposed certain constraints such as minimal or no reserve pits with all the extra mud and wastes hauled for off-location disposal.
In the drilling process, mud materials (barite, water, treating chemicals, etc) are mixed almost continuously to maintain desired mud properties. Drilling mud usage is defined as the volume of mud that is lost with the
drilling operation. This should be contrasted with mud consumption which is the total volume of mud created to support the drilling operation.
Good solids-removal equipment operation, including that of shale shakers, helps prevent these problems.
The dilution required to compensate for the incorporation of 37.9 bbl of drilled solids was the 759 bbl of new mud, less the volume of the drilled solids in the new drilling fluid built, or 721 bbl. This is 19 bbl of dilution per bbl of incorporated solids (721.0 bbl / 37.9 bbl). The calculation for the dilution, that is, the volume of new mud that must be prepared, is