Читать книгу Acoustic and Vibrational Enhanced Oil Recovery - George V. Chilingar - Страница 19

Kapelyushnikov (1954) [17], Gerber and Dvali (1961) [15], Zaks (1952 [40], 1955 [41]), Zhuze and Yushkevich (1959) [42], and Chilingar and Adamson (1964) [9] studied the possibility of oil migration in a gaseous form. Based on some experimental work, Chilingar and Adamson (1964) [9] concluded that some migration of petroleum could have occurred in a gaseous form in the geologic past at high temperatures.

It is important to remember that with increasing polarity of oil, the relative permeability to oil increases and that to water decreases (water cut decreases) (Sinnokrot and Chilingar, 1961 [32]).

Gerber and Dvali (1961) [15] subjected to extraction four samples of rocks with CO₂ at pressures ranging from 100 to 400 kg/cm² and temperatures of 40°C to 74°−90°C. Their findings can be summarized as follows:

1 The bitumens dispersed in rocks and, having composition related to crude oil, can dissolve in compressed gases and migrate together with them.

2 At 200 to 400 kg/cm2 pressure and temperature of 40°C, in dynamic conditions, CO2 can extract not only oils and tars but also asphaltenes and porphyrins from bituminous shales of Ukhta (Russia).

3 The kerosene and the main oil fraction of bitumens can be extracted from the rocks at pressures of 100 to 200 kg/cm2 and temperature of 40°C.

4 Mobile, syngenetic bitumens in the source rocks can dissolve just as easily in the compressed CO2 gas as does petroleum from oil-saturated rocks.

Kapelyushnikov (1954) [17], who studied the P-V-T relationship of oil, gas, and water at pressures up to 500 atmospheres and temperatures up to 100°C, concluded that gaseous oil/gas mixtures move toward the low-pressure areas, dropping the tars and asphaltenes first, followed by medium and lighter components. He also found that at critical pressures, the water and salts present in the oil-bearing strata are also transported together with the gas toward the low pressure areas.