Polishing of secondary treated wastewater using nano-ceramic hybrid PET waste plastic sheets

• Published in: Desalination and water treatment 2021-03, Vol.217, p.214-220
• Main Authors: El-Khateeb, Mohamed A., Kenawy, Sayed H., Khalil, Ahmed M., Samhan, Farag A.
• Format: Article
• Language: English
• Subjects: Downflow hanging non-woven fabric (DHNW); Polyacrylic acid; Polyethylene terephthalate; Upflow anaerobic sludge bed (UASB)
• ISSN: 1944-3986; 1944-3986
• DOI: 10.5004/dwt.2021.26847

This work aims to valorize a considerable part of solid waste that accumulates in the environment as well as the safe reuse of the treated wastewater. A non-woven fabric of polyethylene terephthalate (PET) was coated with a thin layer of a nano-ceramic material. The inhibitory effect of the nano- ceramic material was evaluated against gram +ve (Staphylococcus aureus) and gram –ve bacteria (Salmonella typhimurium and Escherichia coli) using the spread plate technique. Domestic wastewater was treated using a combined upflow anaerobic sludge bed (UASB) followed by a downflow hanging non-woven fabric (DHNW) reactor. The DHNW consisted of four segments (compartments). The hydraulic residence time (HRT) of the UASB reactor was 5 h. The coated sheets were used as a packing material for the DHNW reactor. The levels of chemical oxygen demand (COD), biochemical oxygen demand (BOD), and total suspended solids (TSS) were decreased in the final treated effluent (UASB/DHNW) from 386, 293, and 192 mg/L to 45, 30, and 12 mg/L with total removal states of 88%, 90%, and 90%, respectively. The fecal coliform and E. coli counts were reduced from 4.6 × 107 and 3.5 × 105 to 4.8 × 106 and 7 × 104 MPN/100 mL, respectively. The results showed that the effluent of the combined UASB/DHNW treatment system with the nano-ceramic sheets could be safely reused for different purposes.