Comparison of Three Systems for Biological Greywater Treatment

Abstract

Greywater consists of household wastewater excluding toilet discharges. Three systems were compared for the biological treatment of greywater at a similar hydraulic retention time of approximately 12-13 hours. These systems were aerobic treatment in a sequencing batch reactor, anaerobic treatment in an up-flow anaerobic blanket reactor and combined anaerobic-aerobic treatment (up-flow anaerobic blanket reactor + sequencing batch reactor). Aerobic conditions resulted in a COD removal of 90%, which was significantly higher than 51% removal by anaerobic treatment. The low removal in the anaerobic reactor may have been caused by high concentration of anionic surfactants in the influent (43.5 mg/L) and a poor removal of the colloidal fraction of the COD in up-flow anaerobic sludge blanket reactors. Combined aerobic-anaerobic treatment accomplished a COD removal of 89%, similar to the aerobic treatment alone. Greywater methanization was 32% for the anaerobic system and 25% for the anaerobic-aerobic system, yielding a small amount of energy. Therefore, anaerobic pre-treatment is not feasible and an aerobic system is preferred for the treatment of greywater.

Greywater Characteristics, Treatment Systems, Reuse Strategies and User Perception—a Review

“…Factors that account for such huge disparities are mostly attributed to geographical location, lifestyle, climatic conditions, type of infrastructure, culture and habits, among others. Greywater accounts for up to 75% of the wastewater volume produced by households, and this can increase to about 90% if dry toilets are used (Hernandez Leal et al 2010). It has also been estimated that greywater produced accounts for about 69% of domestic water consumption (Jamrah et al 2011).…”

“…Nitrate (mg/L)5–98%26–8280%–52–63%24 to 58%T. Phosp (mg/L)Up to 100%Up to 71%––Up to 19%10 to 39%FC (CFU)––88.5–99.9%Up to 99%– E. coli (CFU)Up to 100%–88.5–99.9%––Ca (mg/L)Up to 100%–––––Mg (mg/L)Up to 100%–––––Na (mg/L)47%––––– a Al-Hamaiedeh and Bino (2010); Dalahmeh et al (2012); Finley et al (2009); Gross (2008); Parjane and Sane (2011); Zuma et al (2009) b Gross (2008); Gross et al (2007); Travis et al (2010) c Hernandez Leal et al (2010); Krishnan et al (2008); Lamine et al (2007); Scheumann and Kraume (2009) d Friedler et al (2011); Gilboa and Friedler (2008); Pathan et al (2011) e Atanasova et al (2017); Huelgas and Funamizu (2010); Jong et al (2010); Merz et al (2007) f Abdel-Shafy et al (2015); Elmitwalli et al (2007); Hernandez Leal et al (2010)…”

“…c Hernandez Leal et al (2010); Krishnan et al (2008); Lamine et al (2007); Scheumann and Kraume (2009)…”

Assessment of Grey Water Disposal and Different Treatment Options for Domiz Camp in Duhok City

“…A number of biological treatments have been used for grey water treatment. For example, SBR (Hernández Leal et al, 2010;Shin et al, 1998), MBR (Lesjean & Gnirss, 2006;Merz et al, 2007), RBC (Eriksson et al, 2007;Friedler et al, 2005;Nolde, 2000), and CWs (Gross et al, 2007;Li et al, 2004). The MBR technology can be considered as an attractive application for grey water reuse, specifically in urban domestic houses due to high organic loading rate, excellent removal efficiency, stable effluent quality, low sludge production and small footprint (Lazarova et al, 2003).…”

“…(Lodge, 2003). (d) Biological treatment; consists of wide range processes for treatment grey water; fixed film reactors (Hall Jr et al, 1974;Nolde, 2000;Santala et al, 1998;Ward, 2000), biological aerated filters (Birks, 1998;Jenssen et al, 2005;Lodge, 2003); MBR (Hills et al, 2001;Liu, et al, 2005), rotating biological contactor (RBC) (Eriksson et al, 2007;Friedler, et al, 2005;Nolde, 2000), sequencing batch reactor (SBR) (Hernández et al, 2010;Shin et al, 1998), and anaerobic filters (Liu et al, 2005;Šostar-Turk et al, 2005). (e) Extensive treatment; this treatment include constructed wetlands for instance ponds and reed beds.…”