Reliability and efficiency of an advanced tertiary treatment process for wastewater reclamation

Abstract

A reliability study for the reclamation of wastewater treatment plant effluent using continuous sand filtration-multimedia filtration (CSF-MMF) combined with ultrafiltration (UF) and reverse osmosis (RO) has been conducted. The objectives of the research are two-fold: (1) effluent of CSF-MMF can be used for surface water supplementation and (2) permeate of UF-RO can be applied as greenhouse irrigation water. The removal efficiencies for nutrients and electric conductivity (EC) as well as some operational parameters of the pilot plant were investigated. The concentration of T-N, chemical oxygen demand (COD) and turbidity in the filtrate of CSF-MMF with external C-course methanol dosage and FeCl3 dosage could be kept at less than 2.2 mg/L, 35 mg/L and 0.9 NTU respectively. Average EC exceeded the required surface water standard by 10% and it was difficult to meet the low surface water standard for T-P (below 0.15 mg/L). The EC of RO permeate was below 20 μS/cm, which was much lower than the standard for greenhouse irrigation. With frequent back flushes, cleaning in place (CIP) and enhanced cleaning the UF could be operated with a constant permeability of 100 L/(m2·h·bar). An appropriate CIP resulted in a recovery of 47–52% of the RO. The protective cartridge filter prior to the RO should be replaced every 2 weeks.

Water reclamation and reuse

“…Case studies in Cochabamba, Bolivia, showed that better management of the WRRF operation and maintenance could reduce microbial risk levels to acceptable levels and reduce ANNUAL LITERATURE REVIEW ecological risks from nitrogen and phosphorous accumulation in soil when reusing wastewater for irrigation practices (Cossio et al, 2019). Xu, de Koning, and Geng (2019) investigated the reliability and efficiency of continuous sand filtration-multimedia filtration (CSF-MMF) followed by UF and RO for the reclamation of effluent from a WRRF for surface water supplementation and greenhouse irrigation water. They found that filtrate from the CSF-MMF met the surface water standards, except for electric conductivity and total phosphorous.…”

“…Xu, de Koning, and Geng (2019) investigated the reliability and efficiency of continuous sand filtration‐multimedia filtration (CSF‐MMF) followed by UF and RO for the reclamation of effluent from a WRRF for surface water supplementation and greenhouse irrigation water. They found that filtrate from the CSF‐MMF met the surface water standards, except for electric conductivity and total phosphorous.…”

Ecotoxicological effect of enrofloxacin on Spirulina platensis and the corresponding detoxification mechanism

“…5,6 Consequently, it is of great importance to develop a reliable and effective mean for evaluating and reducing ecological risks in aquatic environments. 7…”

“…5,6 Consequently, it is of great importance to develop a reliable and effective mean for evaluating and reducing ecological risks in aquatic environments. 7 Microalgae are a group of photoautotrophic microorganisms and have attracted much attention for their increasing applications in energy and environmental elds. 8 As primary producers, microalgae play a fundamental role in the food chains of aquatic ecosystems and have been used to assess ecotoxicity due to their high sensitivity to xenobiotic pollutants.…”

Performance evaluation of filtration and ultrafiltration for municipal secondary effluent reuse

“…However, the biofilm formation on the membrane has a minor contribution to the membrane fouling mechanism, and the control of the transmembrane pressure parameter through the backwash period has a significant effect on the removal of matter accumulated on the membrane surface (Falsanisi et al, 2010), and also the use of chemicals can enhance backwash cleaning. (Xu et al, 2019). Chemical cleaning process applied to UF membranes has a considerable effect on microbiological quality and also prevents progressive fouling of the permeate zone (Arévalo et al, 2009).…”