crude oil

The problem of crude oil deficit for Ukrainian refineries has been considered. To solve this problem the import of crude from Nigeria has been proposed. Physico-chemical properties of Nigerian oils, namely their fractional composition, potential yield of light fractions were investigated and compared with physico-chemical characteristics of Ukrainian crude oils. The possibility of Nigerian oils processing at JSC “Ukrtatnafta” (Ukraine) was grounded.

Three different macromolecular structures of poly(ethylene oxide-b-propylene oxide) copolymers, used in formulations of commercial demulsifiers for breaking water-in-crude oil emulsions, were investigated. The interfacial activity (), the lower interfacial tension (m), the critical micelle concentration (CMC), the interfacial concentration (Γ) and the molecular area (A) adsorbed at the interface of the surfactant solutions were evaluated. These results were correlated to surfactant performance in coalescing three different asphaltene model emulsions.

The formation of aggregates of a fraction of asphaltenes extracted from Brazilian crude oil was investigated by measuring the interfacial tension and kinematic viscosity of their solutions prepared in different solvents. The interfacial tension results indicate the existence of critical micelle concentration (CMC) levels of the asphaltenes in solvents with solubility parameters sufficiently different from those of the asphaltene tested. The kinematic viscosity measures revealed the formation of aggregates at concentrations above the CMC.

Evaluations of wax inhibitors carried out in laboratories are generally performed on stabilized oil samples, that is, without the presence of natural gas and at atmospheric pressure. Therefore, the effects of two important factors that influence wax solubility – the light fractions and temperature – are not considered, and the results may not reflect what really happens in production lines and facilities.

Petroleum could be seen as a system of asphaltenes dispersed in other petroleum components. The petroleum components excluding the asphaltenes are referred to in this paper as Petroleum Medium that Disperses the Asphaltenes – PMDA). This paper proposes a methodology to determine solubility parameter of the PMDA by identifying a model solvent which, when added to the petroleum, does not affect the asphaltenes phase behavior.

The article deals with the development of technological scheme for refining oils extracted in Iraq. Basic characteristics and physico-chemical properties of Iraq oils have been considered. The main stages of oil refining and processing have been described. Material balances of each processing stage have been calculated.