Nanofiltration as tertiary treatment method for removing trace pharmaceutically active compounds in wastewater from wastewater treatment plants

We surveyed the variation in perfluorinated compound (PFC) concentrations entering urban wastewater treatment plants and then designed an optimal PFCs treatment method based on a pilot test. The PFCs influent concentration was found to be affected by the types of industries and operating rate. The concentration of PFCs in the wastewater treatment effluent was slightly lower than that of the influent. Thus, PFCs had not been adequately removed by the existing biological treatments. The pilot test results showed that about 10% of PFCs was removed by coagulation and precipitation, and the ozone and chlorine test showed that few, if any, PFCs were removed regardless of the oxidant dose. The activated carbon adsorption test showed that the removal significantly increased with empty bed contact time, with about a 60% removal in five minutes and over 90% removal in over 15 minutes. Therefore, a more stable and higher PFCs removal would result from continuous oxidation processes, such as ozone and adsorption processes involving activated carbon, rather than a single biological treatment.

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Identification of pathogen bacteria and protozoa in treated urban wastewaters discharged in the Ebro River (Spain): water reuse possibilities

Water Science & Technology ◽

10.2166/wst.2013.201 ◽

2013 ◽

Vol 68 (3) ◽

pp. 575-583 ◽

Cited By ~ 19

Author(s):

R. Mosteo ◽

M. P. Ormad ◽

P. Goñi ◽

J. Rodríguez-Chueca ◽

A. García ◽

...

Keyword(s):

Wastewater Treatment ◽

Water Reuse ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Research Work ◽

Municipal Wastewater Treatment ◽

Tertiary Treatment ◽

Salmonella Spp ◽

Free Living ◽

Municipal Wastewater Treatment Plants

The aim of this research work is to identify the presence of pathogens, bacteria and protozoa, in different treated urban wastewaters and to relate biological pollution with the processes used in wastewater treatment plants. A study of the possibilities for water reuse is carried out taking into account bacterial and parasite composition. The analysed bacteria and protozoa are: Enterococcus faecalis, Pseudomonas aeruginosa, Staphylococcus aureus, Clostridium perfringens (spore), Salmonella spp., Legionella spp., helminths eggs, Giardia, Cryptosporidium spp. and free-living amoebae (FLA). The selected municipal wastewater treatment plants (MWTPs) are located in Navarra (Spain) and the main difference between them is the use of natural lagoons as tertiary treatment in some plants. The results concerning bacteriological identification showed contamination of mainly faecal origin, and the use of natural lagoons as tertiary treatment in some MWTPs produced an important disinfection effect. Moreover, pathogen parasites such as Giardia and Cryptosporidium were not detected in the samples studied although FLA were identified in all cases.

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