cross polar microscopy on crude

Rheological study of waxy crude oilexample from Cambay basin

reservoir

NAME- Akshaya kumar mishraRoll no-14mpe12

GUIDE-Mr Uttam Bhui

Current Scenario • As production from

conventional oil reserves declines at a rate of about 5% per year, global demand is rising steadily

• In this environment, heavy-parafinic oil is playing an instrumental role in reserve replacement

Complications in heavy crude production

• When the fluid temperature falls below the WAT there is wax deposition in the tubing/piping . Wax deposition will reduce the effective flow area and may lead to complete pipe blockage

• The precipitation of wax components out of the oil is responsible for the changes in waxy crude oil properties, including the gelation of oil and increase in viscosity

• Therefore it is very important to understand the properties and behavior of paraffinic crude so that the design of the facilities can be optimized according to the nature of crude

OBJECTIVE

• The objective of this project is to study rheological properties of waxy crude oils from Cambay basin reservoirs for flow assurance

• Study of crudes in static and dynamic condition at different temperature.

• Study of rheological property of crudes before and after adding different doses of pore point depressant.

• Developing a correlation between above analysis & SARA analysis of crude to form a generalize solution

Instrumentation & analytical Procedure

Physical appearance ,behavior Chemical Composition

Static Conditioning During Cooling

Behavior in Dynamic condition

GCMS , FTIRCross Polar

MicroscopyStudy With Rheometer

CORRELATION OF GATHERED DATA & CONCLUSION

CROSS POLAR MICROSCOPY• Polarizing microscopes are used in the study of thin sections

of minerals and rocks as well as other anisotropic materials (fibers, plastics, etc.).

• Anisotropy is the property of being directionally dependent, as opposed to Isotropy, which implies identical properties in all directions

• This test method consists of determining the wax appearance temperature (WAT, or cloud point) of a crude oil by measuring the temperature at which wax crystals can be seen via microscopy under cross polarized light

• The oil sample is placed between the cross-polarized filters, and any crystalline material present will rotate light allowing the light to pass through the second polarization filter

CROSS-POLARMICROSCOPYBA310Pol

RESULTS

60ºC

45ºC

35ºC

50X

HC1

Oil Temp (F)

Oil Temp (C)

Observation

140 60 No Observation131 55 No Observation122 50 No Observation113 45 No Observation104 40 No Observation96.8 36 Wax crystals appear 91.4 33 Number of crystal

increases rapidly

OBSERVATION :-Macrocrystalline (paraffin) waxes have larger, elongated structures

60ºC

45ºC

35ºC

50X

HC3

Oil Temp (F)

Oil Temp (C)

Observation


increases rapidly


60ºC

45ºC

35ºC

50X

HC4

Oil Temp (F)

Oil Temp (C)

Observation


increases rapidly


60ºC

45ºC

35ºC

50X

PC1

Oil Temp (F)

Oil Temp (C)

Observation


increases rapidly

OBSERVATION :-rounded microcrystalline (naphthene and iso-paraffin) waxes

60ºC

45ºC

35ºC

50X

PC2

Oil Temp (F)

Oil Temp (C)

Observation


increases rapidly


60ºC

45ºC

35ºC

50X

PC3

Oil Temp (F)

Oil Temp (C)

Observation


increases rapidly


CONJECTURE

• The anisotropic nature of wax crystals allows their size and shape to be determined by CPM

• From Studies it has been established that Microcrystalline (paraffin) waxes were found to have larger, elongated structures compared to the smaller, rounded microcrystalline (naphthene and iso-paraffin) waxes.

50XDK24 50XDK3350XHO1

50XHO250XSAE 50XBK19

Macrocrystalline (paraffin) waxes have larger, elongated structures

rounded microcrystalline (naphthene and iso-paraffin) waxes

FURTHER AGENDA OF THE PROJECT1 •Physical properties & Behavior in dynamic condition

•Study with Rheometer

2 •Chemical Composition •FTIR, GCMS

3•PPD TREATMENT•Tests are reperformed after adding different doses of PPD & behavior is monitored

4 •CORRELATION OF GATHERED DATA & CONCLUSION

Rheometery

• Heavy – paraffinic crude tend to change its behavior &physical properties under applied shear stress .

• In this test the rheological properties of crude are studied at different applied shear stresses

FTIR• FTIR- Fourier transform infrared

spectroscopy (FTIR) is a technique which is used to obtain Raman scattering of a solid, liquid or gas

• FTIR radiation is passed through a sample. Some of the infrared radiation is absorbed by the sample and some of it is passed through (transmitted).

• The resulting spectrum represents the molecular absorption and transmission, creating a molecular fingerprint of the sample

GCMS• Gas Chromatography

Mass Spectrometry (GC-MS) is a technique for the analysis and quantization of organic volatile and semi-volatile compounds

• Gas chromatography (GC) is used to separates mixtures into individual components using a temperature-controlled capillary column

• Mass spectrometry (MS) is used to identify the various components from their mass spectra

PPD Treatment • From the above result we observe that different crudes showed

different wax structure . some of them show a rounded microcrystalline structure while other showed larger elongated Macrocrystalline structures .

• So after the test different PPD are selected for different type of wax.• Pour point depressants (also known as PPDs) are polymers that are

designed to control wax crystal formation in lubricants resulting in lower pour point and improved low temperature flow performance

• All the tests are reperfomed by adding different doses of PPD selected , the change in appearance as well as chemical & physical behavior is monitored

THANK YOU

cross polar microscopy on crude

Education