Advanced Treatment of Real Grey Water by SBR Followed by Ultrafiltration—Performance and Fouling Behavior

Abstract

Grey water has been identified as a potential source of water in a number of applications e.g., toilet flushing, laundering in first rinsing, floor cleaning, and irrigation. The major obstacle to the reuse of grey water relates to pathogens, nutrients, and organic matter found in grey water. Therefore, much effort has been put to treat grey water, in order to yield high-quality water deprived of bacteria and with an appropriate value in a wide range of quality parameters (Total Organic Carbon (TOC), nitrate, phosphate, ammonium, pH, and absorbance), similar to the values for tap water. The aim of this study was to treat the real grey water, and turn it into high-quality, safe water. For this purpose, the real grey water was treated by means of a sequential biological reactor (SBR) followed by ultrafiltration. Initially, grey water was treated in a laboratory SBR reactor with a capacity of 3 L, operated in a 24 h cycle. Then, SBR effluent was purified in a cross-flow ultrafiltration setup. Treatment efficiency in SBR and ultrafiltration was assessed using extended physicochemical and microbiological analyses (pH, conductivity, color, absorbance, Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD5), nitrate, phosphate, ammonium, total nitrogen, phenol index, nonionic and anionic surfactants, TOC, Escherichia coli, and enterococci). Additionally, ultrafiltration was evaluated in terms of fouling behavior for three polymer membranes with different MWCO (molecular weight cut-off). The values of quality parameters (pH, conductivity, COD, BOD5, TOC, N-NH4+, N-NO3−, Ntot, and P-PO43−) measured in SBR effluent did not exceed permissible values for wastewater discharged to soil and water. Ultrafiltration provided the high-quality water with very low values of COD (5.8–18.1 mg/L), TOC (0.47–2.19 mg/L), absorbanceUV254 (0.015–0.048 1/cm), color (10–29 mgPt/L) and concentration of nitrate (0.18–0.56 mg/L), phosphate (0.9–2.1 mg/L), ammonium (0.03–0.11 mg/L), and total nitrogen (3.3–4.7 mg/L) as well as lack of E. coli and enterococci. Membrane structural and surface properties did not affect the treatment efficiency, but did influence the fouling behavior.

Investigation of mechanisms of an upflow-downflow siliceous sand filtration system for surfactants bathroom grey water treatment

“…Compared to other filters media used in the literature for grey water surfactant removal, our results are in good agreement with other studies (Bera et al 2013;Kaminska & Marszałek 2020) as they observed almost similar ARE of surfactants on sand filtration and SBR-Ultra filtration systems. At optimum loading rates, our upflow-downflow filtration system compared to a cascading sand filter and constructed wetland systems meet the reuse standard of ,1 mg•L À1 for anionic surfactants as the microbial community was yet acclimatized (Kadewa et al 2010).…”

“…The P/BOD 5 ratio ranged from 0.16 to 0.29 indicates that it is not suitable for the biological treatment of phosphorous (Grady Jr et al 2011). The range of surfactants values in bathroom grey water, which varied from 12 to 16 mg/L, was similar to other literature values where anionic surfactants values average was 15 mg/L (Kaminska & Marszałek 2020). A high faecal coliform count detected in bathroom grey water is undesirable and indicates a greater chance of human illness and infections developing through contact with the wastewater.…”

Application of the Ultrafiltration and Photooxidation Process for the Treatment of Rainwater

“…The volume of the tank is 20 L. In order to determine the efficiency of the ultrafiltration process, rainwater was collected 300 mL each and a physicochemical analysis was carried out. The process was carried out with a water recovery of 75%, due to the design of the reservoir (Kamińska & Marszałek, 2020).…”

Effect of Photooxidation on Nanofiltration Membrane Fouling During Wastewater Treatment from the Confectionery Industry

“…In the first stage of research, four nanofiltration membranes were tested [34]. These wastewaters were subjected to initial purification in the ultrafiltration process.…”