Methods of measuring the fouling tendency of hydrocarbon fluids
A stability of at least one foulant within a hydrocarbon-based fluid sample may be determined where the hydrocarbon-based fluid sample may have or include, but is not limited to a hydrocarbon fluid and foulant particles. The fluid sample may have a viscosity ranging from about 0.5 cSt to about 5000 cSt. The hydrocarbon-based fluid sample may be centrifuged, and a laser light (in the near-infrared region) with a detector may be applied to the hydrocarbon-based fluid sample. At least one transmittance measurement from the laser light passing through the hydrocarbon-based fluid sample may be used to measure foulant flocculation. A foulant stability reserve measurement may be obtained by comparing a first transmittance measurement of the centrifuged hydrocarbon-fluid sample to a second transmittance measurement of a non-centrifuged hydrocarbon-fluid sample.
1. A method to determine a stability of at least one foulant within a hydrocarbon-based fluid sample comprising:
centrifuging a hydrocarbon-based fluid sample comprising a hydrocarbon-based fluid and foulant particles, wherein the hydrocarbon-based fluid sample has a viscosity ranging from about 0.5 cSt to about 5000 cSt;
applying a laser light to the hydrocarbon-based fluid sample, wherein the laser light has a wavelength in the near-infrared region ranging from about 800 nm independently to about 2000 nm;
measuring a first transmittance of the laser light through the hydrocarbon-based fluid sample with a detector; and
comparing the first transmittance measurement to a second transmittance measurement of a non-centrifuged hydrocarbon-fluid sample to determine a distribution of foulant particles within the hydrocarbon-based fluid sample.
2. The method of claim 1 , further comprising analyzing the number or size of flocculated foulant particles by a technique selected from the group consisting of light scattering, light blocking, ultrasound, videomicroscopy, and combinations thereof.
3. The method of claim 2 , wherein the measuring the first transmittance and analyzing the number of flocculated foulant particles occur at the same time or at different times.
4. The method of claim 1 , further comprising adding at least one solvent to the hydrocarbon-based fluid sample at a time selected from the group consisting of about the same time as the centrifuging, before the centrifuging, after the centrifuging, and combinations thereof.
5. The method of claim 4 , wherein the adding at least one solvent occurs in a step-wise manner, and wherein the total amount of the at least one solvent within the hydrocarbon-based fluid sample ranges from about 20 vol % to about 80 vol %.
6. The method of claim 5 , wherein the at least one solvent is selected from the group consisting of heptane, toluene, hexane, pentane, xylene, a paraffinic solvent having a solubility range of about 6.8 to 7.2 (cal/cm3) 1/2 , and combinations thereof.
7. The method of claim 1 , wherein the amount of the hydrocarbon-based fluid within the hydrocarbon-based fluid sample ranges from about 20 vol % to about 100 vol %.
8. The method of claim 1 , wherein the sizes of the flocculated foulant particles are about 0.05 micron or more.
9. The method of claim 1 , wherein the centrifuging occurs for at least 30 seconds.
10. The method of claim 1 , further comprising adding at least one solvent to the hydrocarbon-based fluid prior to centrifuging the hydrocarbon-based fluid sample.
11. The method of claim 1 , wherein the foulant particles are present in the hydrocarbon-based fluid sample in an amount ranging from about 0.01 vol % to about 10 vol %.
12. The method of claim 1 , wherein the hydrocarbon-based fluid sample further comprises a component selected from the group consisting of a dispersant, a foulant inhibitor, and combinations thereof.
13. The method of claim 1 , further comprising heating the hydrocarbon-based fluid sample prior to the method procedure selected from the group consisting of centrifuging, applying the laser light, and combinations thereof.
14. The method of claim 1 , wherein the hydrocarbon-based fluid is selected from the group consisting of a production fluid, crude oil, natural gas condensate, shale oil, shale gas condensate, bitumen, diluted bitumen (dil-bit), refinery fractions, finished fuel, finished petroleum products, and combinations thereof.
15. The method of claim 1 , wherein the foulant particles are selected from the group consisting of asphaltenes, iron sulfides, waxes, coke, sand, ores, clays, hydrates, naphthenates, and combinations thereof.
16. A method to determine a stability of at least one foulant within a hydrocarbon-based fluid sample comprising:
centrifuging a hydrocarbon-based fluid sample comprising a hydrocarbon-based fluid and foulant particles in an amount ranging from about 0.01 vol % to about 10 vol %, wherein the hydrocarbon-based fluid sample has a viscosity ranging from about 0.5 cSt to about 5000 cSt;
adding at least one solvent to the hydrocarbon-based fluid sample at a time selected from the group consisting of about the same time as the centrifuging, before the centrifuging, after the centrifuging, and combinations thereof;
applying a laser light to the hydrocarbon-based fluid sample, wherein the laser light has a wavelength in the near-infrared region ranging from about 800 nm to about 2000 nm;
measuring at least one transmittance of the laser light through the hydrocarbon-based fluid sample with a detector;
comparing the at least one transmittance measurement to a second transmittance measurement of the laser light through a non-centrifuged hydrocarbon-based fluid sample having the effective amount of the at least one solvent at the time of foulant flocculation; and
analyzing the number or size of flocculated foulant particles by a technique selected from the group consisting of light scattering, light blocking, ultrasound, videomicroscopy, and combinations thereof.
17. A method to determine a stability of at least one foulant within a hydrocarbon-based fluid sample comprising in any order:
centrifuging a hydrocarbon-based fluid sample for at least 30 seconds where the hydrocarbon-based fluid sample comprises a hydrocarbon-based fluid and foulant particles selected from the group consisting of asphaltenes, iron sulfides, waxes, coke, sand, ores, clays, hydrates, naphthenates, and combinations thereof;
adding an effective amount of at least one solvent to flocculate at least a portion of the foulant particles;
applying a laser light to the hydrocarbon-based fluid sample, wherein the laser light has a wavelength in the near-infrared region ranging from about 800 nm independently to about 2000 nm;
measuring at least one transmittance of the laser light through the hydrocarbon-based fluid sample with a detector;
comparing the at least one transmittance measurement to a second transmittance measurement of the laser light through a non-centrifuged hydrocarbon-based fluid sample having the effective amount of the at least one solvent at the time of foulant flocculation; and
analyzing the number or size of flocculated foulant particles by a technique selected from the group consisting of light scattering, light blocking, ultrasound, videomicroscopy, and combinations thereof.