Computational fluid dynamics modeling of floating treatment wetland retrofitted stormwater pond: Investigation on design configurations.

Floating Treatment Wetland (FTW) is a cost-effective and easy-to-retrofit device for stormwater treatment. Its treatment efficiency largely depends on the fraction of inflow entering FTW and the residence time within it. Thus hydrodynamics play a crucial role, which is affected by the design configurations of FTW and stormwater pond.

Integrating bioelectrochemical system with aerobic bioreactor for organics removal and caustic recovery from alkaline saline wastewater.

Bioelectrochemical systems (BES) are increasingly being explored as an auxiliary unit process to enhance conventional waste treatment processes. This study proposed and validated the application of a dual-chamber bioelectrochemical cell as an add-on unit for an aerobic bioreactor to facilitate reagent-free pH-correction, organics removal and caustic recovery from an alkaline and saline wastewater. The process was continuously fed (hydraulic retention time (HRT) of 6 h) with a saline (25 g NaCl/L) and alkaline (pH 13) influent containing oxalate (25 mM) and acetate (25 mM) as the target organic impurities present in alumina refinery wastewater.

Review of hydraulics of Floating Treatment Islands retrofitted in waterbodies receiving stormwater.

Stormwater pollution causes an excessive influx of nutrients and metals to the receiving waterbodies (stormwater ponds, lakes, and rivers), which can cause eutrophication and metal toxicity. One of the most cost-effective and eco-friendly solutions to stormwater pollution is constructing Floating Treatment Islands (FTIs) within the waterbodies receiving stormwater runoff. Treatment efficiency of FTIs depends on many factors including plant species, temperature, detention time, and pollutant loading rate.

Rapid start-up of a bioelectrochemical system under alkaline and saline conditions for efficient oxalate removal.

This study examined a new approach for starting up a bioelectrochemical system (BES) for oxalate removal from an alkaline (pH > 12) and saline (NaCl 25 g/L) liquor. An oxalotrophic biofilm pre-grown aerobically onto granular graphite carriers was used directly as both the microbial inoculum and the BES anode. At anode potential of +200 mV (Ag/AgCl) the biofilm readily switched from using oxygen to graphite as sole electron acceptor for oxalate oxidation.

Bioelectrochemical oxidation of organics by alkali-halotolerant anodophilic biofilm under nitrogen-deficient, alkaline and saline conditions.

This work aimed to study the feasibility of using bioelectrochemical systems (BES) for organics removal under alkaline-saline and nitrogen (N) deficient conditions. Two BES inoculated with activated sludge were examined for organics (oxalate, acetate, formate) oxidation under alkaline-saline (pH 9.5, 25g/L NaCl) and N deficient conditions.

Surfactant-enhanced remediation of polycyclic aromatic hydrocarbons: A review.

Polycyclic aromatic hydrocarbons (PAHs) are toxic, mutagenic and carcinogenic organic compounds that are widely present in the environment. The bioremediation of PAHs is an economical and environmentally friendly remediation technique, but it is limited because PAHs have low water solubility and fewer bioavailable properties. The solubility and bioavailability of PAHs can be increased by using surfactants to reduce surface tension and interfacial tension; this method is called surfactant-enhanced remediation (SER).

Sequential solid entrapment and in situ electrolytic alkaline hydrolysis facilitated reagent-free bioelectrochemical treatment of particulate-rich municipal wastewater.

We introduce here a novel process for the treatment of particulate-rich wastewater. A two-stage combined treatment process, consisting of an electrolysis filter and a bioelectrochemical system (BES) configuration was designed and evaluated to remove particulate and soluble organic matter from municipal wastewater. The system was designed such that the electrolysis step was used as a filter, enabling physical removal and in situ alkaline hydrolysis of the entrapped particulate matter.

Assessing the suitability of sediment-type bioelectrochemical systems for organic matter removal from municipal wastewater: a column study.

This study examines the use of bioelectrochemical systems (BES) as an alternative to rock filters for polishing wastewater stabilisation ponds (WSPs) effluent, which often contains soluble chemical oxygen demand (SCOD) and suspended solids mainly as algal biomass. A filter type sediment BES configuration with graphite granules (as the surrogate for rocks in a rock filter) was examined. Three reactor columns were set up to examine three different treatments: (i) open-circuit without current generation; (ii) close-circuit - with current generation; and (iii) control reactor without electrode material.

A bio-anodic filter facilitated entrapment, decomposition and in situ oxidation of algal biomass in wastewater effluent.

This study examined for the first time the use of bioelectrochemical systems (BES) to entrap, decompose and oxidise fresh algal biomass from an algae-laden effluent. The experimental process consisted of a photobioreactor for a continuous production of the algal-laden effluent, and a two-chamber BES equipped with anodic graphite granules and carbon-felt to physically remove and oxidise algal biomass from the influent. Results showed that the BES filter could retain ca.

Polycyclic aromatic hydrocarbons (PAHs) removal by sorption: A review.

Polycyclic aromatic hydrocarbons (PAHs) are organic micro pollutants which are persistent compounds in the environment due to their hydrophobic nature. Concerns over their adverse effects in human health and environment have resulted in extensive studies on various types of PAHs removal methods. Sorption is one of the widely used methods as PAHs possess a great sorptive ability into the solid media and their low aqueous solubility property.