Mechanism of Water Flooding in the Presence of Free Gas

Kyte, J.R.; Stanclift, R.J.; Stephan, Simon; Rapoport, Lorence

doi:10.2118/536-g

Cited by 51 publications

(21 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Conversely, as C moves to ∞, no NWF is residually trapped after imbibition. This purely empirical model was developed to describe observations in the literature of saturation hysteresis resulting from the entrapment of gas in water wet sandstone plugs after imbibition [ Kyte et al ., ; Holmgren and Morse , ]. Higher order empirical models, aimed at describing the more complex behaviour of mixed wetted and oil‐wet systems are also reported in the literature [e.g., Jerauld ; Spiteri et al ., ].…”

Section: Resultsmentioning

confidence: 99%

Capillary trapping quantification in sandstones using NMR relaxometry

Connolly

Vogt

Iglauer

et al. 2017

Water Resources Research

View full text Add to dashboard Cite

Capillary trapping of a non‐wetting phase arising from two‐phase immiscible flow in sedimentary rocks is critical to many geoscience scenarios, including oil and gas recovery, aquifer recharge and, with increasing interest, carbon sequestration. Here we demonstrate the successful use of low field 1H Nuclear Magnetic Resonance [NMR] to quantify capillary trapping; specifically we use transverse relaxation time [T2] time measurements to measure both residual water [wetting phase] content and the surface‐to‐volume ratio distribution (which is proportional to pore size] of the void space occupied by this residual water. Critically we systematically confirm this relationship between T2 and pore size by quantifying inter‐pore magnetic field gradients due to magnetic susceptibility contrast, and demonstrate that our measurements at all water saturations are unaffected. Diffusion in such field gradients can potentially severely distort the T2‐pore size relationship, rendering it unusable. Measurements are performed for nitrogen injection into a range of water‐saturated sandstone plugs at reservoir conditions. Consistent with a water‐wet system, water was preferentially displaced from larger pores while relatively little change was observed in the water occupying smaller pore spaces. The impact of cyclic wetting/non‐wetting fluid injection was explored and indicated that such a regime increased non‐wetting trapping efficiency by the sequential occupation of the most available larger pores by nitrogen. Finally the replacement of nitrogen by CO2 was considered; this revealed that dissolution of paramagnetic minerals from the sandstone caused by its exposure to carbonic acid reduced the in situ bulk fluid T2 relaxation time on a timescale comparable to our core flooding experiments. The implications of this for the T2‐pore size relationship are discussed.

show abstract

Section: Resultsmentioning

confidence: 99%

Capillary trapping quantification in sandstones using NMR relaxometry

Connolly

Vogt

Iglauer

et al. 2017

Water Resources Research

View full text Add to dashboard Cite

show abstract

“…Most relative permeability models that incorporate hysteresis (Jerauld 1997a;Killough 1976;Larsen and Skauge 1998;Lenhard and Parker 1987;Blunt 2000;Lenhard and Oostrom 1998) are based on it. It was developed to predict trapped gas saturation as a function of the initial gas saturation based on published experimental data from water-wet sandstone cores (Holmgren and Morse 1951;Kyte et al 1956;Dardaganian 1957).…”

Section: Development and Validation Of A New Model Of Relative Permeamentioning

confidence: 99%

A New Model of Trapping and Relative Permeability Hysteresis for All Wettability Characteristics

et al. 2008

View full text Add to dashboard Cite

The complex physics of multiphase flow in porous media are usually modeled at the field scale using Darcy-type formulations.The key descriptors of such models are the relative permeabilities to each of the flowing phases. It is well known that, whenever the fluid saturations undergo a cyclic process, relative permeabilities display hysteresis effects.In this paper, we investigate hysteresis in the relative permeability of the hydrocarbon phase in a two-phase system. We propose a new model of trapping and waterflood relative permeability, which is applicable for the entire range of rock wettability conditions. The proposed formulation overcomes some of the limitations of existing trapping and relative permeability models. The new model is validated by means of pore-network simulation of primary drainage and waterflooding. We study the dependence of trapped (residual) hydrocarbon saturation and waterflood relative permeability on several fluid/rock properties, most notably the wettability and the initial water saturation. The new model is able to capture two key features of the observed behavior: (1) nonmonotonicity of the initial-residual curves, which implies that waterflood relative permeabilities cross; and (2) convexity of the waterflood relative permeability curves for oil-wet media caused by layer flow of oil.

show abstract

“…Modeling of relative permeability is discussed in the following section. From early imbibition studies in gas-water and gas-oil systems (Holmgren and Morse, 1951;Dyes, 1954;Kyle et al, 1956;Crowell et al, 1966), and a single oil-water study (Pickell et al, 1966), all primarily conducted on sandstones, Land (1968Land ( , 1971 showed that S * gr increases with increasing S * gi following the relation:…”

Section: Resultsmentioning

confidence: 99%