Mixed Hydrocarbon Oil


With a density of 0.79 to 0.82, mixed hydrocarbon oil is a petroleum-based product. It is a product with low density and viscosity that is utilised as raw material. It is a blend of different oils that includes both lighter and heavier oil.

At reservoir conditions, which are by definition outside the critical zone of the phase envelope, a hydrocarbon combination known as black oil is liquid. It exhibits a relatively low initial gas-oil ratio (GOR) under standard conditions; in other words, the ratio of generated gas to residual dead (gas-free) oil is often lower than 400 m3 standard/m3 standard. When saturation was reached, an isothermal depressurization of a sample of this type of fluid carried out from reservoir static pressure would inevitably result in a bubble point.

This type of fluid contains only a modest amount of “dissolved gas,” which includes light substances like N2, CO2, CH4, and C2H6. Due to the oil’s limited compressibility below saturation pressure, gas liberation results in minimal volume reduction (i.e., shrinkage) in the oil. A phase envelope resembling that of a black oil fluid is shown in Fig. 1.1. The temperature of the reservoir is far below its critical temperature, which means that the temperature and pressure circumstances are significantly to the left of the critical point on the phase envelope. Quality lines (relative liquid and vapor contents inside the envelope) are quite sparse, which causes a relatively small liberation of gas below the bubble point. At the reservoir temperature, Trajectory 1-2-3 displays an isothermal depressurization. Starting with static pressure, it rises to bubble point (about 2800 psia), drops below 1500 psia, and contains about 65% liquid. Approximately 300 psia and 100°F are the surface separator parameters. It is not depicted in Fig. 1.1 because the journey of a fluid particle from static pressure toward the separator is not isothermal (it relies on the temperature profile throughout the column of production (CoP), from reservoir to surface).