SONOZONE TREATMENT ON WASTEWATER TO BE REUSED
UNIVERSITY OF UDINE
Department of Chemistry, Physics and Environment
Prof. Goi Daniele, Dott.ssa Rossi Giada
Via del Cotonificio 108, 33100 Udine
Friuli Venezia Giulia
ENVIRONMENTAL ENGINEERING TEAM
Prof. Eng. Daniele Goi
Expert in environmental sanitary engineering.
PhD Giada Rossi
Expert in advanced oxidation processes for wastewater treatment.
Eng. Valentina Cabbai
Expert in wastewater treatment modeling.
Disinfection(coliforms, E.coli, Salmonella spp., Enterococcus spp.)
Pollutants treatment (aromatic compounds, surfactants, formaldeyde)
Nutrient preservation (phosphate, nitrogen)
WASTEWATER TREATMENT ON PRIMARY EFFLUENT
MBAS anionic surfactants
UV25442 – 52 %
Enterococcus spp.99,92 %
Salmonella spp.99,98 %
Low frequence ultrasounds used as a pre-treatment don't induce pollutants and microorganisms abatement, but they have only a mechanical activity.
Organic matter inside the system is easier to oxidize by ozone thanks to particulate substance disaggregation due to sonication. Sonolitic pretreatment at low frequencies can increase ozone oxidative efficiency.
Phosphate and nitrogen concentrations don't vary during sonozone treatment: wastewater characteristics, useful for carbon, nitrogen and phosphorus reintegration in the water-ground system, are preserved.
Sonozone technology optimizes surfactants and bacteria abatement better than the application of the single techniques.
Anionic surfanctants (MBAS) are degraded by sonozone in the same way if we use a longer ozone treatment and an higher dose of chemical oxidant.
Sonozone disinfection efficiency is more evident on E.coli and coliforms otherwise is less efficient on enterococci.
Several types of wastewater, from civiland industrial wastewater plants, have to be tested for sonozone treatment, in order to prove process effectiveness on samples with different characteristics in terms of organic load, suspended solids and pollutants.
Design and use of pilot plant have to be pursued in order to test bigger volumes of wastewater and simulate real plants function.
In addition, it may be interesting to evaluate the treatment from an economic point of view, calculating costs and energy efficiency in order to identify whether the application can compete with the solutions already existing. Preliminary data indicate that the combined used of ultrasonic and ozone treatment could reduce the costs due to the chemical disinfectant.
The R&D results suggested that sonozone technique is suitable for the use in agro-industrial sector, in particular to treat wastewater, rich in surfactant and bacterial load, to be reuse.
This process treatment could be even applied in wastewater treatment, to refine secondary treatment, in order to implement disinfection and abatement of refractory pollutants. The process should be applied on small plants treating wastewater from little communities or productive realities.
A possible application could be the treatment of wastewater on boards, from mobile kitchens and hospitals, in camping, small settlements or mountain retreat placed in areas of particular environmental interest.