Patent ID: 8028562

Claim:
A system for high pressure gas chromatographic analysis of a fluid sample, the system comprising: a pressure balanced tool housing constructed and adapted for deployment in a wellbore in a subterranean rock formation; a fluid collection system for obtaining the fluid sample downhole; a mobile gas phase of a controllable mobile gas phase source in communication with a controllable expander injector coordinately maintains the fluid sample at pressures similar to a pressure of the subterranean rock formation from which the fluid sample was collected; a flowpath adapted to flow the mobile gas phase and the fluid sample at pressures above 20 atmospheres and at ambient temperatures above 100 degrees Celsius and the controllable expander injector is adapted to convert the fluid sample into a gas phase to inject the fluid sample into the flowpath as a gas; a separation column adapted to operate at high pressures, forming part of the flowpath downstream of the controllable expander injector, for separating a plurality of components within the fluid sample; a detector located downstream of the separation column, measuring at least one property of the gas, thereby generating measurement data representing properties of at least one component of the fluid sample, wherein the flowpath, the controllable expander injector, the separation column and the detector are housed within the tool housing and adapted to operate at pressures approximate to the incoming downhole pressure of the fluid sample from which the fluid sample was collected; and a processor adapted to calculate from the measurement data a value relating to the amount of at least one component of the fluid sample.