Evaluations of conventional, ozone and UV/H2O2 for removal of emerging contaminants and THM-FPs

Abstract

Although potential risk of pharmaceuticals and personal care products (PPCPs) and endocrine disrupting compounds (EDCs) and trihalomethanes to humans is small or unconfirmed, it is advisable to remove these wastewater-related contaminants to increase public confidence and acceptance as a precautionary principle and consequently their elimination or reduction during drinking water treatment is warranted. Experiments were conducted using the dual train pilot-scale conventional treatment plant with ozone and ultraviolet/hydrogen peroxide (UV/H2O2) with three different raw water sources. Reductions of trihalomethanes-formation potentials (THM-FPs) were 8–52%. Ozone was found to decrease THM-FPs while UV/H2O2 was found to increase THM-FPs in most of the experiments under experimental conditions. Conventional treatment poorly removed the selected PPCPs and EDCs while ozone + conventional treatment provided excellent removal. Conventional + UV/H2O2 treatment also demonstrated effective removal. However, removal of PPCPs and EDCs by conventional + UV/H2O2 treatment provided lower efficacy for Sites B and C, likely due to the presence of scavengers such as organics, bicarbonates, carbonates and particles.

Photo- and Electrochemical Water Treatment

“…This section describes some of the studies published in the literature during the years 2009 to 2020. The UV/H 2 O 2 process is studied for removal of carbamazepine, gemfibrozil, ibuprofen, naproxen, and diclofenac from the wastewater matrices 52 wherein only triclosan is completely removed. The degradation of carbamazepine by UV/Cl forms 10,11-epoxy carbamazepine and acridine substituted compounds as TPs of carbamazepine.…”

“…[59][60][61] The results obtained by UV/Cl were compared with UV/H 2 O 2 and it was found that the H 2 O 2 is not totally consumed and subsequently requires another process for removal, making the cost of UV/H 2 O 2 more than that of UV/Cl. 52,53 The photo-Fenton method (Fe 21 /Fe 21 /H 2 O 2 ) eliminates some of the organic contaminants such as ciprofloxacin, oxacillin, chloramphenicol, amoxicillin, ampicillin, and trimethoprim with complete mineralization or partial mineralization, which forms TPs. 25 The chemical reactions involved in the degradation of the ciprofloxacin by the photo-Fenton method and UV/H 2 O 2 take place at the piperazinyl ring and forms a degraded product, as shown in Figure 1.5.…”

Photochemical Degradation of Organic Xenobiotics in Natural Waters

“…A combination of ozone and UV radiation was shown to be effective in the degradation of dinitrotoluene and trinitrotoluene [77] as well as for some insecticides of the carbamate group such as carbofuran [78], for an industrial solvent N-methyl-2-pyrolidone [79], and for the reduction of trihalomethanes formation during drinking water treatment [80].…”

Pilot-Scale Biological Activated Carbon Filtration–Ultrafiltration System for Removing Pharmaceutical and Personal Care Products from River Water

“…The oxidation method exhibited a fast reaction speed and high removal efficiency [15,16]. Borikar et al [17] investigated the pilot-scale advanced oxidation processes (AOPs) for removing various PPCPs. The results showed the superior removal rates of over 95% involving carbamazepine, fluoxetine, naproxen, gemfibrozil, and ibuprofen.…”