Elimination of recalcitrant micropollutants by medium pressure UV-catalyzed bioelectrochemical advanced oxidation process: Influencing factors, transformation pathway and toxicity assessment.

Bio-electro-Fenton (BEF) processes have been widely studied in recent years to remove recalcitrant micropollutants from wastewater. Though promising, it still faces the critical challenge of residual iron and iron sludge in the treated effluent. Thus, an innovative medium-pressure ultraviolet-catalyzed bio-electrochemical system (MUBEC), in which medium-pressure ultraviolet was employed as an alternative to iron for in-situ HO activation, was developed for the removal of recalcitrant micropollutants.

A novel persulfate-photo-bioelectrochemical hybrid system promoting the degradation of refractory micropollutants at neutral pH.

Bio-electro-Fenton is emerging as an alternative technology for the efficient and cost-effective removal of refractory micropollutants. Though promising, there are still several challenges that limit its wide application, including acidic operating conditions (pH at 2-3), the addition of supporting electrolytes (e.g.

Ecotoxicity and biodegradation of the bacteriostatic 3,3',4',5-tetrachlorosalicylanilide (TSCA) compared to the structurally similar bactericide triclosan.

This article studies the ecotoxicity of 3,3',4',5-tetrachlorosalicylanilide (TCSA) using different bioassays and examines its fate in activated sludge batch experiments. Despite of the common use of TCSA as chemical uncoupler in wastewater treatment systems and as preservative in several products, limited data has been published for its ecotoxicity, while no information is available for its biodegradation. Among different bioassays, the highest toxicity of TSCA was noticed for Daphna magna (48-h LC: 0.

Ecotoxicity Evaluation of Pure Peracetic Acid (PAA) after Eliminating Hydrogen Peroxide from Commercial PAA.

In recent years, peracetic acid (PAA) has gained a lot of attention as an alternative disinfectant to chlorine-based disinfectants in the water industry. Commercial PAA solutions contain both PAA and hydrogen peroxide (HP), and the degradation of HP is slower than PAA when it is used for disinfection. All previous toxicity studies have been based on commercial PAA, and variance in toxicity values have been observed due to different PAA:HP ratios.

Colorimetric Quantification Methods for Peracetic Acid together with Hydrogen Peroxide for Water Disinfection Process Control.

Peracetic acid (PAA) water solutions is applied for disinfection of industry systems, food products and non-potable water. Commercially available peracetic acid is always supplied mixed with hydrogen peroxide (HO). HO degrade slower than the peracetic acid which creates a need to quantify both peroxides separately to gauge the disinfection power of the solution and the residuals.

Acute toxicity and risk evaluation of the CSO disinfectants performic acid, peracetic acid, chlorine dioxide and their by-products hydrogen peroxide and chlorite.

The ecotoxicological evaluation of combined sewer overflow (CSO) disinfectants, with their degradation products, is important for ensuring safe use. For this form of toxicity, data for organisms representing different trophic levels are needed. We studied the toxicity of the alternative disinfectants peracetic acid (PAA), performic acid (PFA) and chlorine dioxide (ClO) and their degradation products hydrogen peroxide (HO) and chlorite (ClO) on Vibrio fischeri and Daphnia magna.

Treatment of Arctic wastewater by chemical coagulation, UV and peracetic acid disinfection.

Conventional wastewater treatment is challenging in the Arctic region due to the cold climate and scattered population. Thus, no wastewater treatment plant exists in Greenland, and raw wastewater is discharged directly to nearby waterbodies without treatment. We investigated the efficiency of physicochemical wastewater treatment, in Kangerlussuaq, Greenland.

Algal toxicity of the alternative disinfectants performic acid (PFA), peracetic acid (PAA), chlorine dioxide (ClO) and their by-products hydrogen peroxide (HO) and chlorite (ClO).

Environmental effect evaluation of disinfection of combined sewer overflow events with alternative chemical disinfectants requires that the environmental toxicity of the disinfectants and the main by-products of their use are known. Many disinfectants degrade quickly in water which should be included in the evaluation of both their toxicity as determined in standardized tests and their possible negative effect in the water environment. Here we evaluated according to the standardized ISO 8692 test the toxicity towards the green microalgae, Pseudokirchneriella subcapitata, of three disinfectants: performic acid (PFA), peracetic acid (PAA) and chlorine dioxide (ClO) as well as two by-products of their use: hydrogen peroxide (HO) and chlorite.

Biodegradation of pharmaceuticals in hospital wastewater by staged Moving Bed Biofilm Reactors (MBBR).

Hospital wastewater represents a significant input of pharmaceuticals into municipal wastewater. As Moving Bed Biofilm Reactors (MBBRs) appear to remove organic micro-pollutants, hospital wastewater was treated with a pilot plant consisting of three MBBRs in series. The removal of pharmaceuticals was studied in two experiments: 1) A batch experiment where pharmaceuticals were spiked to each reactor and 2) a continuous flow experiment at native concentrations.

Biodegradation of pharmaceuticals in hospital wastewater by a hybrid biofilm and activated sludge system (Hybas).

Hospital wastewater contributes a significant input of pharmaceuticals into municipal wastewater. The combination of suspended activated sludge and biofilm processes, as stand-alone or as hybrid process (hybrid biofilm and activated sludge system (Hybas™)) has been suggested as a possible solution for hospital wastewater treatment. To investigate the potential of such a hybrid system for the removal of pharmaceuticals in hospital wastewater a pilot plant consisting of a series of one activated sludge reactor, two Hybas™ reactors and one moving bed biofilm reactor (MBBR) has been established and adapted during 10 months of continuous operation.

Chemical disinfection of combined sewer overflow waters using performic acid or peracetic acids.

We investigated the possibility of applying performic acid (PFA) and peracetic acid (PAA) for disinfection of combined sewer overflow (CSO) in existing CSO management infrastructures. The disinfection power of PFA and PAA towards Escherichia coli (E. coli) and Enterococcus was studied in batch-scale and pre-field experiments.