Patent ID: 7075063
Filing Date: 2006-07-11
Classification: G01V

Abstract:
1. A method for determining phase transition pressure of downhole retrograde condensate, the method comprising: a) producing a time-series of fluorescence values by measuring fluorescence from a single-phase flow of OBM-contaminated formation fluid in a downhole cell; b) producing an OBM-contamination value from the time-series of fluorescence values; c) setting pressure in the cell at a transition boundary; d) producing an apparent phase transition pressure value by setting apparent phase transition pressure value equal to pressure of fluid in the cell; e) producing an OBM-contamination value, and a value of apparent phase transition pressure, for each cycle of a plurality of cycles by repeating steps (a)–(d); and f) determining the value of phase transition pressure using apparent phase transition pressure values and OBM-contamination values.