Comparison of wastewater treatment efficiencies in packed bed bioreactors according to the nature of materials

Treatment of seawater salinity sewage with intermittent sand bioreactors

“…This varies from the findings of Ruane et al (2014) that stratified sand columns removed more COD than single layer columns when treating pre-treated dairy soiled wastewater. A fine sand system showed greater removal of COD and ammonia than coarse sand at the same depth, both treating septic tank effluent (Wang et al 2019). These conflicting results within the literature each showed variation between designs, whereas the current study indicates both the proposed three-layer and one-layer ISB designs can treat seawater salinity septic tank effluent.…”

“…These systems had nearly complete nitrification of influent ammonia (Rodgers et al 2011) and .98% ammonia removal (Sodamade et al 2014). Wang et al (2019) found that a sand filter removed 96% of COD and 98% of ammonia from septic tank effluent at three times the loading rate of the current study. Widrig et al (1996) found nearly complete nitrification and BOD effluent values below discharge limits when operating ISBs treating artificial septic tank effluent with a loading rate six times that used in the current study.…”

“…Visible indicators of water backing up were observed at the top of the fine sand layer in the three-layer ISB columns and on the top of the one-layer ISB columns. Several studies indicate that in both stratified and single layer designs, the top layer is where most organic matter build up is detected (Ruane et al 2014;Ochoa et al 2015;Wang et al 2019) Organic matter build-up was noticed in the top 3 cm of both the stratified and single layer columns tested by Ruane et al (2014). They found that the stratified columns had organic matter build up deeper into the columns, with limited build up seen in the single layer columns at 12 cm depth (Ruane et al 2014).…”

“…A comparison of one-layer and three-layer ISBs treating secondary effluent from a woodchip filter treating dairy soiled water showed similar ammonia removal but significantly different COD removal between the two designs (Ruane et al 2014). A fine sand system showed greater removal of COD and ammonia than coarse sand at the same depth, both treating septic tank effluent (Wang et al 2019). Yet, fine sand filters have also been found to clog more quickly than coarse sand systems of the same depth when treating domestic greywater (Ochoa et al 2015).…”

Ouvrages d’assainissement non collectif – Analyse du retour d’expérience sous les angles de la stabilité, de la pérennité et des usages

“…La mise en oeuvre des tranchées d'épandage et des massifs filtrants reconstitués demande un travail soigné, codifié dans le DTU 64.1 [AFNOR,2013 b].Les filtres à sable horizontaux, retirés du DTU depuis 1998, présentent une certaine fragilité mais restent autorisés par la réglementation avec des adaptations techniques[LIÉNARD, 2010] tout en conservant leur statut de technique non courante.L'utilisation de sable concassé issu de carrière, comme alternative à l'emploi de sable de rivière dans une logique de développement durable semble prometteuse[LIENARD et al, 2000 ; WANG et al, 2015WANG et al, , 2019.Les points faibles de ces techniques : La qualité des matériaux constitutifs des fosses septiques[Douillard, 2018] et des postes de relevage souffre d'une fragilité structurelle dont les exigences actuelles se résument à celles du marquage CE. Cela se traduit sur le terrain, par des déformations des cuves en polyéthylène, expliquées par des épaisseurs insuffisantes de leurs enveloppes et par une qualité de matière insuffisante.…”