Predicting clean fluid composition and properties with a rapid formation tester pumpout

A system for estimating clean fluid composition, comprising:

• a downhole fluid sampling tool comprising a fluid analysis module that obtains fluid samples that have a contamination level that is not less than five percent of the fluid sample while the downhole fluid sampling tool is disposed in a wellbore;
• and
• a processing unit configured to:
• predict a clean fluid sample of the fluid from at least one sensor response on the fluid analysis module using an asymptote analysis and an equation of state, wherein the equation of state utilizes one or more component mole fractions of the fluid sample;
• and
• apply a robust regression method on at least one sensor response, wherein the robust regression method is computed as scoresfit=A+BXvβ, where A and B are constants determined by a regression method, v is a formation fluid pumpout accumulated volume, and β is a density decay rate.

A system for estimating clean fluid composition, comprising:

• a downhole fluid sampling tool comprising a fluid analysis module that obtains a fluid sample while the downhole fluid sampling tool is disposed in a wellbore;
• and
• a processing unit configured to:
• predict a clean fluid sample of the fluid sample from at least one sensor response on the fluid analysis module using an asymptote analysis and an equation of state, wherein the equation of state utilizes one or more component mole fractions of the fluid sample, and
• apply a robust regression method on at least one sensor response, wherein the robust regression method is computed as scoresfit=A+BXvβ, where A and B are constants determined by a regression method, v is a formation fluid pumpout accumulated volume, and β is a density decay rate.