Influence of Precipitates on Hydraulic Performance of Permeable Reactive Barrier Filters

Improving the sustainability of granular iron/pumice systems for water treatment

“…Contaminant removal also implies iron corrosion (Lavine et el., 2001;You et al, 2005;Jiao et al, 2009;Ghauch et al, 2011;Gheju and Balcu 2011). Therefore, due to the volumetric expansive nature of this process ('prerequisite 1'), the remediation of contaminated groundwater necessarily results in the gradual clogging of the Fe 0 PRB, and thus in the deterioration of the permeable barrier hydraulic conductivity (permeability loss) over time (Zhang and Gillham, 2005;Courcelles et al, 2011;Knowles et al, 2011;Jeen et al, 2012;Miyajima, 2012;Noubactep, 2013a).…”

“…The gradual clogging (permeability loss) of Fe 0 filtration systems has several origins: (i) biological activities like biofilm growth or biocorrosion, (ii) chemical processes like (hydr)oxide or calcite precipitation, (iii) physical processes allowing the retention of fine particles in the PRB pores, and (iv) production and accumulation of gases (mainly H 2 ). Pores clogging could generate a decrease in treatment performance and the bypass of untreated contaminated groundwater (Courcelles et al, 2011;Knowles et al, 2011;Jeen et al, 2012). Therefore, PRBs clogging issues will require costintensive reactive material substitution, if satisfactory operational performance has to be maintained.…”

Effect of Pumice and Sand on the Sustainability of Granular Iron Beds for the Aqueous Removal of CuII, NiII, and ZnII

“…Among the proposed models in the literature, the Kozeny-Carman equation is often considered to evaluate the evolution of the hydraulic conductivity [59]. This equation was developed after considering a porous material as an assembly of capillary tubes and yielded the hydraulic conductivity K as function of the porosity Φ, the specific surface S (m 2 /kg of solids) and a factor C to take into account the shape and tortuosity of channels.…”

Características de la arena sílica de Alvarado, Veracruz, México, como material para barreras reactivas permeables, para la remediación de acuíferos contaminados con lixiviados de basureros no controlados

“…El análisis granulométrico resultante (tabla 2) de la arena sílica de las costas de Alvarado, Veracruz, México, determinó que el 99.67 % de las partículas tiene un tamaño de 0.707 mm. Esta homogeneidad en el tamaño de las partículas permitirá asegurar un flujo uniforme en las BRP , y una conductividad hidráulica adecuada para la retención de iones metálicos divalentes (Courcelles et al, 2011), mediante el mecanismo de adsorción por el medio mineral (ITRC, 2011), lo que permitirá minimizar las limitaciones de flujo del agua de los acuíferos subterráneos, ya que por su tamaño homogéneo no se presentaría el bloqueo entre los espacios intergranulares (Faisal, 2018).…”