Methods and apparatus of downhole fluid analysis

A downhole fluid sampling and characterization apparatus configured for operation downhole, within a borehole, comprising:

• a fluid sampling and analysis module, the fluid sampling and analysis module comprising:
• a flowline for fluids withdrawn from a formation to flow through the fluid sampling and analysis module downhole, within a borehole, the flowline having a first end for the fluids to enter and a second end for the fluids to exit the fluid sampling and analysis
• a first selectively operable device and a second selectively operable device structured and arranged with respect to the flowline for isolating a quantity of the fluids in a portion of the flowline between the first and second selectively operable device;
• and
• at least one sensor connected to the portion of the flowline between the first and second selectively operable device for measuring parameters of interest downhole, within a borehole, relating to the fluids in the flowline, wherein;
• the portion of the flowline for isolating the fluids comprising:
• a bypass flowline, the first and second selectively operable device being structured and arranged for isolating fluids in the bypass flowline, and
• a circulation line interconnecting a first end of the bypass flowline with a second end of the bypass flowline such that fluids isolated between the first and second selectively operable device can circulate in a closed loop formed by the circulation line and the bypass flowline;
• and
• the fluid analysis module further comprising:
• a circulation pump for circulating fluids in the closed loop of the circulation line and the bypass flowline.

A method of downhole sampling and characterization of formation fluids utilizing a downhole tool comprising a fluid analysis module positioned within a borehole having a flowline for flowing formation fluids through the fluid analysis module, the method comprising:

• monitoring at least a first parameter of interest relating to formation fluids flowing in the flowline downhole, within a borehole;
• when a predetermined criterion for the first parameter of interest is satisfied, restricting flow of the formation fluids in the flowline downhole by operation of a first selectively operable device and a second selectively operable device of the fluid analysis module to isolate formation fluids in a portion of the flowline of the fluid analysis module downhole between the first and second selectively operable device;
• and
• characterizing the isolated fluids by operation downhole of one or more sensor on the flowline between the first and second selectively operable device.

A method of downhole sampling and characterization of formation fluids utilizing a downhole tool comprising a fluid analysis module positioned within a borehole having a flowline for flowing formation fluids through the fluid analysis module, the method comprising:

• monitoring at least a first parameter of interest relating to formation fluids flowing in the flowline;
• when a predetermined criterion for the first parameter of interest is satisfied, restricting flow of the formation fluids in the flowline by operation of a first selectively operable device and a second selectively operable device of the fluid analysis module to isolate formation fluids in a portion of the flowline of the fluid analysis module between the first and second selectively operable device;
• and
• characterizing the isolated fluids including determining one or more fluid property of the isolated fluids by operation of one or more sensor on the flowline between the first and second selectively operable device including changing fluid pressure of the isolated fluids by varying volume of the isolated fluids before determining one or more fluid property.

A method of downhole sampling and characterization of formation fluids utilizing a downhole tool comprising a fluid analysis module positioned within a borehole having a flowline for flowing formation fluids through the fluid analysis module, the method comprising:

• monitoring at least a first parameter of interest relating to formation fluids flowing in the flowline;
• when a predetermined criterion for the first parameter of interest is satisfied, restricting flow of the formation fluids in the flowline by operation of a first selectively operable device and a second selectively operable device of the fluid analysis module to isolate formation fluids in a portion of the flowline of the fluid analysis module between the first and second selectively operable device;
• and
• characterizing the isolated fluids by operation of one or more sensor on the flowline between the first and second selectively operable device including determining phase behavior of the isolated fluids while circulating the fluids in the closed loop and
• circulating the isolated fluids in a closed loop of the flowline while characterizing the isolated fluids.

A tool configured to be located downhole for sampling and characterizing formation fluids located downhole in an oilfield reservoir, comprising;

• a fluid analysis module, the fluid analysis module comprising:
• a flowline for fluids withdrawn from a formation downhole to flow through the fluid analysis module, the flowline having a first end for the fluids to enter and a second end for the fluids to exit the fluid analysis module;
• the flowline comprising;
• a bypass flowline and a circulation line interconnecting a first end of the bypass flowline with a second end of the bypass flowline such that fluids can circulate in the circulation line and the bypass flowline;
• and
• the fluid analysis module further comprising:
• a circulation pump for circulating fluids in the circulation line and the bypass flowline;
• at least one sensor situated on the bypass flowline for measuring parameters of interest relating to the fluids in the bypass flowline;
• and
• a first selectively operable device and a second selectively operable device structured and alTanged with respect to the flowline for isolating a quantity of the fluids in the bypass flowline between the first and second selectively operable device
• the at least one sensor comprises one or more of a density sensor;
• a pressure sensor;
• a temperature sensor;
• a bubble/gas sensor;
• a MEMS based sensor;
• an imager;
• and a scattering sensor, wherein the at least one sensor measures parameters of interest relating to fluids isolated in the bypass flowline;
• and
• the fluid analysis module further comprising:
• one or more of a spectral sensor optically coupled to the flowline;
• a fluorescence and gas sensor, a chemical sensor;
• and a resistivity sensor;
• structured and arranged with respect to the flowline for measuring parameters of interest relating to fluids flowing through the flowline.

A downhole fluid sampling and characterization apparatus configured for operation downhole, within a borehole, comprising:

• a fluid sampling and analysis module, the fluid sampling and analysis module comprising:
• a flowline for fluids withdrawn from a formation to flow through the fluid sampling and analysis module downhole, within a borehole, the flowline having a first end for the fluids to enter and a second end for the fluids to exit the fluid sampling and analysis module;
• a bypass flowline connected to said flowline for receiving fluids from said flowline for sampling and analysis;
• a first selectively operable valve positioned within said bypass flowline at an initial end of said bypass flowline and a second selectively operable valve positioned within said bypass flowline at an outlet end of said bypass flowline and arranged with respect to the bypass flowline for isolating a quantity of the fluids in a portion of the bypass flowline between the first and second selectively operable valves;
• and
• at least one sensor connected to the portion of the bypass flowline between the first and second selectively operable device for measuring parameters of interest downhole, within a borehole, relating to the fluids in the flowline wherein the at least one sensor comprises at least one of:
• an optical spectrometer and an optical cell, an optical spectrometer and a refractometer, a fluorescence refraction detector, an imager, a scattering detector for detecting particles within the bypass line, and an ultrasonic transducer.

A downhole fluid sampling and characterization apparatus configured for operation downhole, within a borehole, comprising:

• a fluid sampling and analysis module, the fluid sampling and analysis module comprising:
• a flowline for fluids withdrawn from a formation to flow through the fluid sampling and analysis module downhole, within a borehole, the flowline having a first end for the fluids to enter and a second end for the fluids to exit the fluid sampling and analysis module;
• a bypass flowline connected to said flowline for receiving fluids from said flowline for sampling and analysis;
• a first selectively operable valve positioned within said bypass flowline at an initial end of said bypass flowline and a second selectively operable valve positioned within said bypass flowline at an outlet end of said bypass flowline and arranged with respect to the bypass flowline for isolating a quantity of the fluids in a portion of the bypass flowline between the first and second selectively operable valves;
• at least one sensor connected to the portion of the bypass flowline between the first and second selectively operable device for measuring parameters of interest downhole, within a borehole, relating to the fluids in the flowline;
• a circulation line connected at one end to said bypass flowline downstream of the first valve positioned within said bypass flowline and upstream of the second valve positioned within said bypass flowline;
• and
• a circulation pump connected in series with said circulation line for circulating fluid within said bypass flowline.

A downhole fluid sampling and characterization apparatus configured for operation downhole, within a borehole, comprising:

• a fluid sampling and analysis module, the fluid sampling and analysis module comprising:
• a flowline for fluids withdrawn from a formation to flow through the fluid sampling and analysis module downhole, within a borehole, the flowline having a first end for the fluids to enter and a second end for the fluids to exit the fluid sampling and analysis module;
• a bypass flowline connected to said flowline for receiving fluids from said flowline for sampling and analysis;
• a first selectively operable valve positioned within said bypass flowline at an initial end of said bypass flowline and a second selectively operable valve positioned within said bypass flowline at an outlet end of said bypass flowline and arranged with respect to the bypass flowline for isolating a quantity of the fluids in a portion of the bypass flowline between the first and second selectively operable valves;
• at least one sensor connected to the portion of the bypass flowline between the first and second selectively operable device for measuring parameters of interest downhole, within a borehole, relating to the fluids in the flowline;
• and
• at least another sensor connected in series with the flowline for fluids withdrawn from a formation.