Extractive deasphalting as a method of obtaining asphalt binders and low-viscosity deasphalted hydrocarbon feedstock from natural bitumen

The peculiarities of the composition of natural bitumen from Russian Federation deposits give rise to further processing and transportation problems due to necessity of construction of processing units close to their production areas. In order to solve this problem, a method of pretreatment of natural bitumen was proposed, as a result, potential asphalt binders and low-viscosity deasphalted oil suitable for transportation to refineries are produced. Based on experimental data, the optimal conditions for the process were selected. It was recommended to carry out the first stage of crude preparation, namely thermomechanical dehydration of bitumen, with an end-point for distillation of 150 °C. This solved the problem of stable water-hydrocarbon emulsions and further dewatering of bitumen, and excluded the possibility of destruction reactions resulting in more unstable hydrocarbon compounds. At the next stage, it was proposed to carry out the process of deasphalting of bitumen with acetone at a solvent:crude ratio of 3:1. Therefore, production of deasphalted oil, with viscosity close to that of natural crude oil, and asphalt, as a feedstock for the production of universal road bitumen, intended for both summer and winter operating conditions, was shown