Dead Oil Contamination Analysis DOCA

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DOCA: Dead Oil Contamination and Compositional Analysis

DOCA Wellsite Services

Determination of synthetic drilling fluid contamination:
Dead Oil Contamination and Compositional Analysis (DOCA) is a component of the wellsite analysis services, primarily concerned with providing real-time, on-site analysis of captured hydrocarbon samples to determine the degree of contamination with synthetic drilling fluids.

A significant drilling advantage is available through the use of synthetic base drilling fluids, and their widespread use in offshore environments, has mirrored this fact. An unfortunate consequence of the use of synthetic drilling fluid is that bottom hole samples collected using open hole samplers (RDT/MDT/RCI) frequently have unacceptable levels of synthetic drilling fluid contamination. Contamination levels of >5% for black oils and >2% for condensate systems can make these fluids unfit for phase behavior (PVT) or flow assurance testing. Because the accuracy of down hole contamination measurements is limited, rapid, on-site, independent quantification of the level of contamination is required to provide an operator with swift validation of fluid samples.

Wellsite dead oil evaluation:
DOCA provides rapid quantification of drilling fluid contamination at the wellsite. DOCA works on the small amount of dead oil recovered from the sample chamber coupler during sampler recovery/transfer operations. The analysis is GC based and totally self-contained. A 110V power source is the only requirement at the field location. No pressurized gas cylinders are transported to, or required at the field. The results are automatically generated and displayed in tabular and graphical form. The automated regression analysis, provides significant information about the sample including level of contamination with synthetic fluid and projected properties of the uncontaminated sample.

A Valuable Wellsite Resource:
DOCA is ideally suited to generate dead oil compositional analysis, and in this capacity has found a home in the traditional mud loggers trailer. DOCA represents a powerful and versatile tool that the exploration/production staff can utilize to generate a basic understanding of a prospect and validate fluid samples on-site and in real time.

DOCA applications: