The effect of double layer overlap on measured streaming currents for toluene flowing through sandstone cores

Hydrodynamic thickness of petroleum oil adsorbed layers in the pores of reservoir rocks

“…The contribution of irreducible water film to measured streaming currents in a non-aqueous system decreased, while rock pore diameter (porosity), liquid flow rate (i.e. charge flow rate), and the development of adsorption thickness increased [30,34,35]. As asphaltene concentrations increased in toluene, the rock core surface potential numerically decreased and stabilized at small positive values.…”

Consequences of the nanoporosity of cellulosic fibers on their streaming potential and their interactions with cationic polyelectrolytes

“…Let us further assume that at a very low electrical conductivity only the outermost surfaces significantly contribute to the streaming potential results. Such an assumption is expected to be true in cases where the DebyeHu¨ckel length is larger relative to the characteristic size of pores (Hunter 1981;Kozak and Davis 1986;Miller et al 1992;Wan 1997;Bernabe´1998;Revil et al 1999;Alkafeef et al 2001). In common terms, electrokinetic effects, such as zeta potential, can be suppressed within very small pores due to the fact that there is not sufficient space to accommodate an ionic double layer when the ionic strength is very low.…”

“…Other work suggests that flow does occur through gel layers (Makino et al 1995). pores, in comparison to kraft fibers (Berthold and Salme´n 1997). In addition, the sizes of pores within the cell walls of fibers are expected to affect the degree to which electrokinetic effects are suppressed under conditions of low ionic strength (Hunter 1981;Kozak and Davis 1986;Miller et al 1992;Wan 1997;Bernabe´1998;Revil et al 1999;Alkafeef et al 2001). In light of these issues, further work involving well characterized systems is justified.…”

Streaming Currents in a Single Nanofluidic Channel

“…It has also been suggested that streaming currents in fluidic channels may provide a simple and effective means of converting hydrostatic pressure differences into electrical energy [11], and that this process becomes particularly efficient in the nano regime where double layers overlap [10]. Streaming currents have been primarily studied on systems involving many channels in parallel, using materials such as sandstone cores [12], porous glass [11], and columns packed with latex beads [13]. While studies have appeared on single channels in the micron range [6,14,15], nanofabrication now permits us to investigate streaming currents in well-defined, nanoscale geometries where double layers may overlap.…”