NOx control Articles

In this study, iron oxide modified sands with nano-pores (IOMSNP) were enveloped in biofilm (B-IOMSNP) in order to treat the ammonium-nitrogen (NH4+-N) in micro-polluted raw water. The biomass, optimum backwashing conditions, treatment efficiency, and surface morphological properties of the B-IOMSNP were investigated via bio-filtration experiments. The raw quartz sands (RQS) and IOMSNP ...

Oct. 10, 2015

By IWA Publishing

NDMA formation from treated wastewater is one of the concerns in water reuse. This study focused on NDMA formation potential (NDMAFP) removal in wastewater treated effluent by UV/H2O2 technology. A UV/H2O2 system was tested for the removal performance on both organic precursors and NDMAFP. The system consisted of a low pressure ultra-violet (LPUV) with an intensity ...

Sep. 14, 2015

By IWA Publishing

Autotrophic denitrification with sulphide using nitrate (R1) and nitrite (R2) as electron acceptor was investigated at bench scale. Different solids retention times (SRT) (5 and 20 d) have been tested in R1 while R2 was operated at SRT = 13 d. The results indicated that the process allows complete sulphide removal to be achieved in all tested conditions. Tested sulphide loads were ...

Aug. 6, 2015

By IWA Publishing

A continuous upflow biofilm reactor packed with ceramsite was constructed for nitrate removal under an anaerobic atmosphere without an organic carbon source. Denitrifying bacteria, Pseudomonas sp. W1, Pseudomonas sp. W2 and Microbacterium sp. W5, were added to the bioreactor as inocula. Nitrate concentration, nitrite accumulation and nitrogen removal ...

Jul. 24, 2015

By IWA Publishing

The combination of nitrogen recovery and pharmaceutical removal processes for livestock urine treatment were investigated to suppress the discharge of pollutants and recover nitrogen as resources. We combined methylene urea synthesis from urea and adsorption and photocatalytic decomposition of sulfonamide antibiotic using rotating advanced oxidation contactor (RAOC) contained for obtaining both ...

Jul. 16, 2015

By IWA Publishing

An acidification metabolite such as volatile fatty acids (VFAs) and ethanol could be used as denitrification carbon sources for solving the difficult problem of carbon source shortages and low nitrogen removal efficiency. A proper control of environmental factors could be essential for obtaining the optimal contents of VFAs and ethanol. In this study, suspended solids (SS), oxidation reduction ...

Jul. 7, 2015

By IWA Publishing

The bacterial community composition of a down-flow sponge-based trickling filter treating upflow anaerobic sludge blanket (UASB) effluent was investigated by pyrosequencing. Bacterial community composition considerably changed along the reactor and over the operational period. The dominant phyla detected were Proteobacteria, Verrucomicrobia, and ...

Jun. 29, 2015

By IWA Publishing

As of January 1, 2015 the U.S. Environmental Protection Agency (U.S. EPA) has been implementing the Cross-State Air Pollution Rule (CSAPR) through a Federal Implementation Plan (FIP) that primarily impacts electric generating units (EGUs).   This article reviews the transition of the Clear Air Interstate Rule and nitrogen oxide (NO2), sulfur dioxide ...

Jun. 26, 2015

By All4 Inc.

A novel and integrated biofilm process – the sulfate reduction (SR) and mixotrophic (MR) sulfide-utilization denitrification process (SMSD) – was recently proposed for sulfate treatment and sulfur recovery. The process consisted of two bioreactors: a 5.1 L anaerobic upflow reactor for SR, and a 3.5 L anaerobic upflow reactor for MR desulfurization–denitrification. The ...

Jun. 12, 2015

By IWA Publishing

Reporting by Member States under Directive 2001/81/EC of the European Parliament and of the Council of 23 October 2001 on national emission ceilings for certain atmospheric pollutants This report describes the most recent emission inventory information provided by the Member States of the European Union (EU) at the end of 2014, under Directive 2001/81/EC of the European Parliament and of the ...

Jun. 11, 2015

By European Environment Agency (EEA)

South African wastewater facility saves energy and meets nutrient removal regulations Many small communities across the U.S. and around the globe are struggling to meet more stringent nitrification of ammonia requirements on a tighter budget. When a South African community could not meet its state requirements and struggled with a failing rotor disc system, the town’s officials ...

Jun. 2, 2015

By Aeration Industries International (AII)

The main challenge in implementing shortcut nitrogen removal processes for mainstream wastewater treatment is the out-selection of nitrite oxidizing bacteria (NOB) to limit nitrate production. A model-based approach was utilized to simulate the impact of individual features of process control strategies to achieve NO−2-N shunt via NOB ...

Mar. 27, 2015

By IWA Publishing

An upflow anaerobic biofilter (AF) was developed to investigate anaerobic ammonium-oxidizing (ANAMMOX) efficiency in treating low-strength wastewater at ambient temperature (15.3–23.2 °C). Denaturing gradient gel electrophoresis (DGGE) and fluorescence in situ hybridization were used to investigate treatment effects on the microbial community. Stepwise decreases in influent ...

Mar. 16, 2015

By IWA Publishing

Proper characterization of nanoparticle (NP) interactions with environmentally relevant bacteria under representative conditions is necessary to enable their sustainable manufacture, use, and disposal. Previous nanotoxicology research based on planktonic growth does not adequately explore biofilms, which serve as the predominant mode of bacterial growth in natural and engineered environments. ...

Dec. 30, 2014

By John Wiley & Sons, Ltd.

In this study, two horizontal subsurface-flow constructed wetlands (CWs) (planted and unplanted) were constructed and compared to investigate the effects of vegetation on nitrogen removal and anammox (anaerobic ammonium oxidation) spatial distribution and enrichment. Calamus (Acorus calamus L.), which has a large root system, was selected as the vegetation. Removal of total nitrogen from the ...

Oct. 29, 2014

By IWA Publishing

Numerical simulation is currently used to help design low NOx devices for aircraft engines. In order to improve the prediction of pollutant species, combustion models based on tabulated chemistry have been commonly used in recent years. However, the short time scales of usual flamelet manifolds can lead to errors concerning the NO prediction in post flame area, as shown in this paper. Thus, a new ...

Oct. 28, 2014

By Inderscience Publishers

Conventional and single-stage anaerobic ammonium oxidation (ANAMMOX) was carried out in bench-scale reactors to treat chlortetracycline (CTC) wastewater. The total nitrogen (TN) removal efficiency and rate for conventional ANAMMOX was 66.6 ± 5.9% and 2.7 ± 0.2 kg N/(m3·d), respectively, which was 58.6 ± 3.8% and 1.2 ± 0.1 kg ...

Sep. 29, 2014

By IWA Publishing

Example: Uranium enrichment Similar tasks: Nitric acid caprolactam production When uranium ore is converted into uranium hexafluoride (UF6) for uranium enrichment employing the diffusion process, or also when producing nitric acid and nitrogenous fertilizers for farming, laughing gas is produced by several undesirable side reactions. Thermal decomposition ...

Aug. 30, 2014

By Chemisch Thermische Prozesstechnik GmbH / CTP Air Pollution Control

TiO 2 films codoped with V cations and N anions were synthesised by RF-magnetron sputtering. The incorporation of V and N in TiO 2 lattice produces isolated energy levels near the conduction and valence bands, respectively, causing an effective narrowing of the band gap to 2.5 eV. Recombination of photo-charges was reduced by depositing multilayer films of indium tin oxide ...

Aug. 18, 2014

By Inderscience Publishers

Sludge ozonation is a promising technology for dealing with the increasing challenge of excess sludge treatment and disposal. However, nitrogen behavior during sludge ozonation and subsequent biological removal remains unclear. To clarify the feasibility and stability of oxidizing organic nitrogen (released during sludge ozonation) in the bioreactor (but not during ozonation), and the best ...

Jul. 23, 2014

By IWA Publishing