3. Physical chemical pour point reduction method 

This is a comprehensive pour point reduction method. The method requires adding pour point depressant into crude oil and heat treating the crude oil with depressant. 

In order to compare heat treatment with comprehensive treatment, the viscosity temperature curves of untreated crude oil, heat treated crude oil and comprehensive treated crude oil can be measured.

The figure shows the viscosity temperature curve of a waxy crude oil in the above three cases. During heat treatment, the crude oil is heated to 85 ℃ and then cooled; During comprehensive treatment, 100mg / L pour point depressant (copolymer of ethylene and vinyl acetate) is added to the crude oil at 60 ℃, then it is heated to 85 ℃ and cooled.

It can be seen that:

The crude oil after comprehensive treatment has better low-temperature fluidity than that after heat treatment, which is reflected in the lower viscosity of crude oil after wax precipitation point and the wider temperature range of crude oil with Newtonian characteristics (i.e. the temperature of abnormal point is lower).

Crude oil pour point depressant

The freezing point refers to the maximum temperature at which the measured oil sample just loses fluidity under the specified thermal and shear conditions, which reflects the difficulty of wax crystal particles forming network structure.

Crude oil pour point depressant is a kind of oil-soluble high molecular organic compound or polymer. Adding an appropriate amount of pour point depressant to waxy crude oil can change the wax crystal morphology and structure in crude oil under certain conditions, so as to significantly reduce the freezing point of waxy crude oil and improve the low-temperature flow performance of waxy crude oil. Therefore, pour point depressant is also called flow lmprover.