Why do we study crude oil waxes? Wax deposition is billion-dollar problem in the oil industry. When the temperature of the oil in the pipeline drops low enough, wax molecules tend to crystallize an deposit on the pipe wall.

The low temperature affects crude oil transportation in cold environment pipelines, causing problems such as wax deposition. Flow assurance in hydrocarbon pipelines is critical due to the precipitation of the solid phase of wax on the pipe wall, which causes pressure anomalies and an artificial blockage, resulting in a reduction or interruption in production. When the temperature of the pipe wall (inlet coolant temperature) falls below the wax appearance temperature, wax can precipitate as a solid phase.

Phenomenon

According to a study on wax deposition, the magnitude of the diffusion of the heavier waxy components decreases as the oil temperature decreases.

The magnitude of the diffusion of the lighter waxy components, on the other hand, increases.

A significant phenomenon is that the mass of the deposit increases as the temperature of the oil decreases.

Olympus BX53TRF Microscope
with
Hexon Radiant RHX125 Hot Stage

Analysis procedure

The Crude oil WAX sample was heated to 80 deg C and held at this temperature for 1 min. Magnification 50X. And then cooled at 1 Deg C per minute

80 Deg C

40 Deg C

26 Deg C

200x  , 80 Deg c

200x ,40 Deg c

200x , 30 Deg c

200x ,25 Deg c

Magnification 200x

Conclusion

One of the most significant fluid flow assurance challenges confronting petroleum engineers is wax deposition on cold-weather hydrocarbon pipelines. Wax can precipitate as a solid phase when the temperature of the pipe wall falls below the wax appearance temperature. It restricts crude oil flow in the pipeline, causing pressure anomalies and an artificial blockage, resulting in production reduction or interruption. 

The Hexon Instruments Radiant RHX125 Hot Stage is useful for crude oil wax disposition research. Which enables the user to easily place the sample on the Hot Stage and study the temperature change to develop a solution for the petroleum industries.