Promoting on-site urban wastewater reuse through MBR–RO treatment

Abstract

A compact membrane bioreactor and reverse osmosis (MBR-RO) system was installed in KEREFYT, EYDAP, in order to assess the potential reuse applications of the reclaimed water. The feed of the unit was directly drained from the sewage network. The objective of the study was to examine the effluent's water quality. This was performed through a series of lab measurements as well as from data taken by a series of on-line sensors installed in several points of the unit. This paper discusses the presence of contaminants, biological and chemical, in the MBR's permeate, as well as the RO's effluent, thus determining the system's efficiency. This study has shown that the MBR-RO system can produce a high quality water. The RO effluent's quality in terms of organic content (0,9 mg/L BOD 5 and not detectable TSS), Ammonium (0,25 mg/L), Total Nitrogen (12 mg/L), turbidity (0,32 NTU), E. Coli (not detectable) and Total Coliforms (not detectable) could fully meet the water quality requirements for reclaimed water, as dictated by the Greek legislation. However, it is considered necessary to conduct further tests in order to be totally in line with the Greek legislation. The remaining parameters that have to be measured are heavy metals, microorganic pollutants and priority pollutants.

Sewer Mining as a Distributed Intervention for Water-Energy-Materials in the Circular Economy Suitable for Dense Urban Environments: A Real World Demonstration in the City of Athens

“…A smaller pilot SM unit has been installed and set in operation in EYDAP's premises in Metamorphosis area in the context of the Dessin FP7 project since 2015 until now. This unit proved its efficiency and stability while produces effluent water suitable for any kind of use [11,13].…”

“…In particular, the process starts when screened sewage is stored temporarily in a buffer tank (9) of filtered wastewater which communicates with a denitrification tank (10) through a bottom window (11). Inside the denitrification tank (10), anaerobic microorganisms turn nitrates to nitrogen gas which naturally leaves the system.…”

“…Regarding the SM unit's cost, the total capital cost of produced water was calculated to be 0.36 €/m 3 , while the operational cost amounts to 0.5 €/m 3 , which produces a quite moderate total cost of 0.86 €/m 3 of produced water [11].…”

“…A technology that can combine flexible and decentralised wastewater treatment as well as advanced treatment technologies is called sewer mining (SM). SM technology was originally pioneered in Australia in 2006 [7][8][9][10] and was first tested successfully in Greece through an FP7 project called Dessin in 2015 [6,11].…”

A Monte-Carlo-Based Method for the Optimal Placement and Operation Scheduling of Sewer Mining Units in Urban Wastewater Networks

“…In the present study, the daily sewage amount pumped out of the network is set to 10 m 3 . This value is selected in compliance with the SM unit's capacity of the Athens pilot SM scheme presented in Plevri et al [45]. Moreover, the pump's capacity is equal to 5 m 3 /day.…”