Role op Clay in Oil Reservoirs

Influence of the Clay Content and Type of Algerian Sandstone Rock Samples on Water–Oil Relative Permeabilities

“…In addition to that, the waterflooding technique might generate corrosion of equipment. ,, Among the parameters mentioned above, the mineralogical composition of the rock, represented essentially by the presence of clays, seems to substantially influence the oil recovery during the waterflooding technique. It is generally recognized, at the laboratory-scale measurements and those obtained on petroleum deposits, that oil wells have low injectivities with respect to water as a result of the presence of clays. − For this reason, the presence of clay in the sandstone reservoirs is critical during secondary recovery operations by water. Subsequent work has shown that the presence of clays in petroleum reservoirs can have the following effects: the permeability during the secondary recovery operation with water is lower than that of air permeability; reduction of the permeability will not occur immediately in the waterflooding process; and the ionic concentration of water greatly affects the reduction of the permeability. ,− Because of the influence of clay on permeability, the water relative permeability and the displacement of the oil by water can be expected to be affected to a large extent by the presence of clays.…”

“…It is generally recognized, at the laboratory-scale measurements and those obtained on petroleum deposits, that oil wells have low injectivities with respect to water as a result of the presence of clays. − For this reason, the presence of clay in the sandstone reservoirs is critical during secondary recovery operations by water. Subsequent work has shown that the presence of clays in petroleum reservoirs can have the following effects: the permeability during the secondary recovery operation with water is lower than that of air permeability; reduction of the permeability will not occur immediately in the waterflooding process; and the ionic concentration of water greatly affects the reduction of the permeability. ,− Because of the influence of clay on permeability, the water relative permeability and the displacement of the oil by water can be expected to be affected to a large extent by the presence of clays. In addition, the water/oil relative permeability curves may also be affected by the injection pressure, the pressure gradient, and the gravitational gradient that may decrease the capillary forces; the relative permeability trend is strongly dependent upon the invaded phase as well-demonstrated in the work of Akbarabadi and Piri, in which brine relative permeability of the drainage process initially exhibits a very rapid decline followed by a gradual reduction with a decrease in brine saturation.…”

Effect of Kaolinite on Water-in-Oil Emulsion Formed by Steam Injection during Tertiary Oil Recovery: A Case Study of an Omani Heavy Oil Sandstone Reservoir with a High Kaolinite Sludge Content

“…10 As a result of their large internal surface area along with the high salinity within oil reservoirs, they tend to react rapidly and easily. 15 Johansen et al 16 showed that kaolinite adsorbs water vapor weakly. Moreover, the presence of kaolinite is reported to alter the efficiency of not only thermal methods but also non-thermal methods.…”

Tipificação de argilas em sedimentos turbidíticos usando um modelo empírico para estimativa da capacidade de troca catiônica

“…Assim, de acordo com Johnston (1952), os diversos tipos de argila, cujas características são distintas, influenciam de diferentes maneiras as propriedades físicas de uma rocha. Ruhovets and Fertl (1982), por exemplo, ressalta que a redução na permeabilidade do reservatório é mais severa no caso de presença de esmectita; a ilita e a clorita tendem a reduzir a permeabilidade e a porosidade do reservatório menos acentuadamente que a esmectita, e a caulinita, causa uma redução significativamente menor que a da esmectita na permebilidade da rocha.…”

“…Nessa ordem, a capacidade de troca catiônica das argilas varia decrescentemente. Ou seja: espera-se que os efeitos das argilas sobre a produção de óleo & gás sejam maiores na presença de esmectitas, e menor na presença de caulinitas (Johnston, 1952). Neste trabalho, apresentamos um procedimento simples para classificar argilas baseado na estimativa da CTC usando um modelo empírico obtido por uma regressão não linear do tipo exponencial.…”