Secondary effluent reclamation: combination of pre-treatment and disinfection technologies.
A study was carried out to evaluate the efficiency of secondary effluent additional treatment, using a combination of pre-treatments (ring filter, physico-chemical and infiltration-percolation) followed by disinfection methods (chlorine dioxide, peracetic acid and ultraviolet light). Three different indicator microorganisms were determined: E. coli, total coliforms and somatic bacteriophages. The results show better efficiency of physico-chemical and infiltration-percolation processes. Bacteriophages were eliminated to a lesser extent than bacterial indicators in all the treatment systems. Chlorine dioxide and peracetic acid seems to be more efficient in disinfection than ultraviolet light when a ring filter is the pre-treatment used. For the same doses and contact times, the efficiency of the disinfection methods is higher when the pre-treatment used is the physico-chemical or the infiltration-percolation system. The final effluent quality from the physico-chemical treatment train and the infiltration-percolation treatment train, followed by the disinfectants, achieves an E. coli content that allows the reuse in most of the uses described in the Spanish legislation for wastewater reuse.
Alcalde
L
L
Soil Science Lab, University of Barcelona, Av. Joan XXIII s/n, 08028, Barcelona, Spain. lalcalde@ub.edu
Folch
M
M
Tapias
J C
JC
Martínez
F
F
Enguídanos
S
S
Bernácer
I
I
D017606:Chlorine Compounds / Q000737:chemistry; D005374:Filtration; D010087:Oxides / Q000737:chemistry; D010463:Peracetic Acid / Q000737:chemistry; D014466:Ultraviolet Rays; D014865:Waste Disposal, Fluid / Q000379:methods*; D018508:Water Purification / Q000379:methods*
D017606:Chlorine Compounds; D010087:Oxides; C025109:chlorine dioxide; D010463:Peracetic Acid