scholarly journals Factors Affecting the Simultaneous Removal of Nitrate and Reactive Black 5 Dye via Hydrogen-Based Denitrification

Water ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 922
Author(s):  
Tippawan Singhopon ◽  
Kenta Shinoda ◽  
Suphatchai Rujakom ◽  
Futaba Kazama
Keyword(s):  
Flow Rate ◽  
Nitrogen Removal ◽  
Removal Rate ◽  
Textile Wastewater ◽  
Pollutant Removal ◽  
Bacterial Degradation ◽  
Reactive Black 5 ◽  
Simultaneous Removal ◽  
Removal Rates ◽  
Similar Treatment

Textile wastewater (TW) contains toxic pollutants that pose both environmental and human health risks. Reportedly, some of these pollutants, including NO3-, NO2- and reactive black 5 (RB-5) dye, can be removed via hydrogen-based denitrification (HD); however, it is still unclear how different factors affect their simultaneous removal. This study aimed to investigate the effect of H2 flow rate, the sparging cycle of air and H2, and initial dye concentration on the TW treatment process. Thus, two reactors, an anaerobic HD reactor and a combined aerobic/anaerobic HD reactor, were used to investigate the treatment performance. The results obtained that increasing the H2 flow rate in the anaerobic HD reactor increased nitrogen removal and decolorization removal rates. Further, increasing the time for anaerobic treatment significantly enhanced the pollutant removal rate in the combined reactor. Furthermore, an increase in initial dye concentration resulted in lower nitrogen removal rates. Additionally, some of the dye was decolorized during the HD process via bacterial degradation, and increasing the initial dye concentration resulted in a decrease in the decolorization rate. Bacterial communities, including Xanthomonadaceae, Rhodocyclaceae, and Thauera spp., are presented as the microbial species that play a key role in the mechanisms related to nitrogen removal and RB-5 decolorization under both HD conditions. However, both reactors showed similar treatment efficiencies; hence, based on these results, the use of a combined aerobic/anaerobic HD system should be used to reduce organic/inorganic pollutant contents in real textile wastewater before discharging is recommended.

An Experimental Study on Compatible Solute Ectoine Dosing of High Salinity Wastewater

2014 ◽  
Vol 955-959 ◽  
pp. 1907-1910
Author(s):  
Su Chen ◽  
Lei Chao ◽  
Ning Chen ◽  
Lin Shan Wang ◽  
Xue Shao ◽  
...  
Keyword(s):  
Nitrogen Removal ◽  
Waste Treatment ◽  
High Salinity ◽  
Removal Rate ◽  
Ammonia Nitrogen ◽  
Ammonium Nitrogen ◽  
Treatment Efficiency ◽  
Removal Rates ◽  
Cod Removal Rate ◽  
Salinity Wastewater

When the reactor is added with ectoine of concentrations of 0, 0.1, 1 and 10 mmol/L, the impacts on brine waste treatment efficiency are investigated. The results show that the outflow COD and ammonia nitrogen removal rates are the highest, when the ectoine concentration is 0.1 mmol/L. The brine waste treatment efficiency under addition of ectoine of 1 and 10 mmol/L is even worse than that without ectoine addition. It can be preliminarily determined that the best ectoine dosage is in between 0.1-1.0 mmol/L. When ectoine concentrations added in reactors are 0.2, 0.5, 0.8 and 1.0 mmol/L, the results show that the average reactor outflow COD and ammonia nitrogen removal rates are increased compared with those of reactor without adding ectoine. But when ectoine of 1.0 mmol/L is added, the outflow COD and ammonia nitrogen removal rates decrease. When ectoine dosage is 0.5 mmol/L, the reactor outflow COD and ammonia nitrogen values are the lowest, the removal rates are the highest, the average COD removal rate is 74.46%, and the average ammonium nitrogen removal rate is 54.97%. Compared with reactor without adding ectoine, COD and ammonium nitrogen removal rates are increased by 13.16% and 26.81%. Therefore, the best dosage of ectoine is 0.5 mmol/L.

Dissolved oxygen as a factor influencing nitrogen removal rates in a one-stage system with partial nitritation and Anammox process

2011 ◽  
Vol 64 (5) ◽  
pp. 1009-1015 ◽  
Author(s):  
G. Cema ◽  
E. Płaza ◽  
J. Trela ◽  
J. Surmacz-Górska
Keyword(s):  
Dissolved Oxygen ◽  
Oxygen Concentration ◽  
Nitrogen Removal ◽  
Pilot Plant ◽  
Removal Rate ◽  
Waste Water Treatment Plant ◽  
Removal Rates ◽  
Partial Nitritation ◽  
Do Concentration ◽  
Anammox Process

A biofilm system with Kaldnes biofilm carrier was used in these studies to cultivate bacteria responsible for both partial nitritation and Anammox processes. Due to co-existence of oxygen and oxygen-free zones within the biofilm depth, both processes can occur in a single reactor. Oxygen that inhibits the Anammox process is consumed in the outer layer of the biofilm and in this way Anammox bacteria are protected from oxygen. The impact of oxygen concentration on nitrogen removal rates was investigated in the pilot plant (2.1 m3), supplied with reject water from the Himmerfjärden Waste Water Treatment Plant. The results of batch tests showed that the highest nitrogen removal rates were obtained for a dissolved oxygen (DO) concentration around 3 g O2 m−3. At a DO concentration of 4 g O2 m−3, an increase of nitrite and nitrate nitrogen concentrations in the batch reactor were observed. The average nitrogen removal rate in the pilot plant during a whole operating period oscillated around 1.3 g N m−2d−1 (0.3 ± 0.1 kg N m−3d−1) at the average dissolved oxygen concentration of 2.3 g O2 m−3. The maximum value of a nitrogen removal rate amounted to 1.9 g N m−2d−1 (0.47 kg N m−3d−1) and was observed for a DO concentration equal to 2.5 g O2 m−3. It was observed that increase of biofilm thickness during the operational period, had no influence on nitrogen removal rates in the pilot plant.

scholarly journals Hydrogenotrophic denitrification for treating nitrate contaminated without/with reactive black 5 dye

2020 ◽  
Vol 10 (3) ◽  
pp. 200-213
Author(s):  
Tippawan Singhopon ◽  
Kenta Shinoda ◽  
Suphatchai Rujakom ◽  
Futaba Kazama
Keyword(s):  
Treatment Time ◽  
Removal Rate ◽  
Textile Wastewater ◽  
The Other ◽  
Reactive Black 5 ◽  
Combined Process ◽  
Anaerobic Reactors ◽  
Aerobic Reactor ◽  
Set Up ◽  
Gas Supply

Abstract NO3-N and dye colors discharged from textile wastewater pose environmental problems in Thailand. This study aimed to observe the nitrogen removal rate (NRR) with and without RB-5 color contamination via hydrogenotrophic denitrification (HD) processing, which uses H2 gas as electron donor to reduce NO3-N and NO2-N; comparing with bioreactors treatment to evaluate systems that can simultaneously remove NO3-N and dye color. Five reactors under different operation and gas supply conditions were set-up under HRT of 24 h, including an aerobic reactor using air, two anaerobic reactors using argon and H2, and a combined process using intermittent air/argon and air/H2. NRR without dye varied between 45 and 90% for H2 and air/H2 by HD processing, while it was completely removed when adding color. H2 and air/H2 reactors experienced partial decolorization of approximately 20–30%, whereas the other three reactors remained unchanged. Effluent of NO3-N were close to wastewater standards, but the color was still easy to detect, which indicated that the treatment time needs to be sufficient. In conclusion, HD and intermittent air/H2 processing can completely remove NO3-N and NO2-N when contaminated with RB-5 color. Furthermore, RB-5 did not affect the NRR, whereas some particles of dye color can also reduce in these processes.

Influence of Flow Field on Simultaneous Removal of Nitrogen and Carbon by Membrane Aerated Biofilm Reactor

2014 ◽  
Vol 694 ◽  
pp. 372-376
Author(s):  
Nan Zhang ◽  
Yun Wu ◽  
Hong Wei Zhang ◽  
Hui Jia
Keyword(s):  
Removal Rate ◽  
Ccd Camera ◽  
Ammonia Nitrogen ◽  
Biofilm Reactor ◽  
Simultaneous Removal ◽  
Circulation Flow ◽  
Electron Microscopic ◽  
Removal Rates ◽  
Flow Rates ◽  
Biofilm Thickness

The characteristics of removing COD and nitrogen simultaneously in membrane aerated biofilm reactor (MABR) was investigated in different packing densities and circulation flow rates. The results show that better removal rates of COD and ammonia nitrogen are found under the packing density of 30%, which removal rates are 76% and 65% respectively. Observations through the electron microscopic and CCD camera reveal that the biofilm have a layered structure and the stable biofilm thickness is 1.652 mm. When the circulation flow rate is 7.62 L·min-1, the highest removal rate of total nitrogen is 70%, meanwhile, the efficient mass transfer of the biofilm is ensured.

scholarly journals Kinetic Modeling of VOC Photocatalytic Degradation Using a Process at Different Reactor Configurations and Scales

2016 ◽  
Vol 14 (1) ◽  
pp. 395-405 ◽  
Author(s):  
Aymen Amine Assadi ◽  
Bouzaza Abdelkrim ◽  
Wolbert Dominique
Keyword(s):  
Photocatalytic Degradation ◽  
Removal Efficiency ◽  
Flow Rate ◽  
Removal Rate ◽  
Pollutant Removal ◽  
Inlet Concentration ◽  
Operational Parameters ◽  
Flow Reactors ◽  
Photocatalytic Reactors ◽  
Continuous Flow Reactors

AbstractThis work investigated the performance of isovaleraldehyde (3-methylbutanal) removal from gas streams in photocatalytic reactors at room temperature. The feasibility of pollutant removal using the up-scaled reactor was systematically assessed by monitoring the removal efficiency at different operational parameters, such as geometries of reactor, air flow rate and inlet concentration. A proposal modeling for scaling up the photocatalytic reactors is described and detailed in this present study. In this context, the photocatalytic degradation of isovaleraldehyde (Isoval) in gas phase is studied. In fact, the removal rate has been compared at different continuous flow reactors: a photocatalytic tangential reactor (PTR), planar reactor and P5000 pilot. The effects of the inlet concentration, flow rate, geometries and size of reactors on the removal efficiency are also studied. A kinetic model taking into account the mass transfer step is developed. The modeling is done by introducing an equivalent intermediate (EI) formed by the photo-oxidation of Isoval. This new approach has substantially improved the agreement between modeling and experiments with a satisfactory overall description of the mineralization from lab to pilot scales.

Nitrogen removal rates at a technical-scale pilot plant with the one-stage partial nitritation/Anammox process

2006 ◽  
Vol 54 (8) ◽  
pp. 209-217 ◽  
Author(s):  
G. Cema ◽  
B. Szatkowska ◽  
E. Plaza ◽  
J. Trela ◽  
J. Surmacz-Górska
Keyword(s):  
Nitrogen Removal ◽  
Pilot Plant ◽  
Removal Rate ◽  
New Technology ◽  
Anaerobic Bacteria ◽  
Ammonium Nitrogen ◽  
Anammox Bacteria ◽  
Removal Rates ◽  
Partial Nitritation ◽  
Batch Tests

Traditional nitrification/denitrification is not suitable for nitrogen removal when wastewater contains high concentrations of ammonium nitrogen and low concentrations of biodegradable carbon. Recently, a deammonification process was developed and proposed as a new technology for treatment of such streams. This process relies on a stable interaction between aerobic bacteria Nitrosomonas, that accomplish partial nitritation and anaerobic bacteria Planctomycetales, which conduct the Anammox reaction. Simultaneous performance of these two processes can lead to a complete autotrophic nitrogen removal in one single reactor. The experiments where nitrogen was removed in one reactor were performed at a technical-scale moving-bed pilot plant, filled with Kaldnes rings and supplied with supernatant after dewatering of digested sludge. It was found that a nitrogen removal rate obtained at the pilot plant was 1.9 g m−2d−1. Parallel to the pilot plant run, a series of batch tests were carried out under anoxic and aerobic conditions. Within the batch tests, where the pilot plant's conditions were simulated, removal rates reached up to 3 g N m−2d−1. Moreover, the batch tests with inhibition of Nitrosomonas showed that only the Anammox bacteria (not anoxic removal by Nitrosomonas) are responsible for nitrogen removal.

scholarly journals Study of Carbonaceous and Nitrogenous Pollutant Removal Efficiencies in a Hybrid Membrane Bioreactor

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Victor S. Ruys ◽  
Kamel Zerari ◽  
Isabelle Seyssiecq ◽  
Nicolas Roche
Keyword(s):  
Total Nitrogen ◽  
Nitrogen Removal ◽  
Membrane Bioreactor ◽  
Membrane Separation ◽  
Removal Rate ◽  
Hybrid Membrane ◽  
Pollutant Removal ◽  
Organic Removal ◽  
N Removal ◽  
Total Nitrogen Removal

A hybrid membrane bioreactor (HMBR) comprises activated sludge (free biomass), a biofilm (supported biomass), and a membrane separation. A laboratory pilot-scale HMBR was operated for seven months with high organic loads of both carbonic and nitrogen pollutants. Several experiments were conducted to investigate the influence of the height of the packing bed (27 cm, 50 cm, and 0 cm) and the effect of the concentration of dissolved oxygen (DO) on the organic removal rate, total nitrogen removal rate (TN), and ammonium removal. The organic removal rate was always >95% and mostly >98%. The NH4+-N and TN removal rates were directly related to DO. NH4+-N removal rate reached 100% and was mostly >99% with a concentration of DO > 0.1 mg/L, whereas the NO3--N removal rate was differentially affected depending on the level of DO. The removal rate increased when the concentration of DO was optimal for simultaneous nitrification and denitrification, which was between 0.1 and 0.5 mg/l, and the TN removal rate was consequently high. The removal rate decreased when DO was high and denitrification was consequently low thereby reducing the TN removal rate. This implies that high levels of DO (>1 mg/L) limit the denitrification process and low levels of DO (<0.1 mg/L) limit the nitrification process and hence total nitrogen removal in the bioreactor.

Analysis of organic removal rates in the aerated submerged fixed film process

1998 ◽  
Vol 38 (8-9) ◽  
pp. 213-221 ◽  
Author(s):  
Mohamed F. Hamoda ◽  
Ibrahim A. Al-Ghusain
Keyword(s):  
Pilot Plant ◽  
Removal Rate ◽  
Domestic Wastewater ◽  
Removal Rates ◽  
Hydraulic Loading ◽  
Organic Removal ◽  
Wide Range ◽  
Fixed Film ◽  
Cod Removal Rate ◽  
And Performance

Performance data from a pilot-plant employing the four-stage aerated submerged fixed film (ASFF) process treating domestic wastewater were analyzed to examine the organic removal rates. The process has shown high BOD removal efficiencies (&gt; 90%) over a wide range of hydraulic loading rates (0.04 to 0.68 m3/m2·d). It could also cope with high hydraulic and organic loadings with minimal loss in efficiency due to the large amount of immobilized biomass attained. The organic (BOD and COD) removal rate was influenced by the hydraulic loadings applied, but organic removal rates of up to 104 kg BOD/ m2·d were obtained at a hydraulic loading rate of 0.68 m3/m2·d. A Semi-empirical model for the bio-oxidation of organics in the ASFF process has been formulated and rate constants were calculated based on statistical analysis of pilot-plant data. The relationships obtained are very useful for analyzing the design and performance of the ASFF process and a variety of attached growth processes.

The comparison of trichloroethylene removal rates by methane- and aromatic-utilizing microorganisms

1998 ◽  
Vol 38 (7) ◽  
pp. 19-24 ◽  
Author(s):  
C.-J. Lu ◽  
C. M. Lee ◽  
M.-S. Chung
Keyword(s):  
Cell Concentration ◽  
Removal Rate ◽  
Carbon Sources ◽  
Batch Reactors ◽  
Initial Cell Concentration ◽  
Removal Rates ◽  
Initial Cell ◽  
Toluene Concentration ◽  
Cell Source ◽  
Removal Efficiencies

The comparison of TCE cometabolic removal by methane, toluene, and phenol utilizers was conducted with a series of batch reactors. Methane, toluene, or phenol enriched microorganisms were used as cell source. The initial cell concentration was about 107 cfu/mL. Methane, toluene, and phenol could be readily biodegraded resulting in the cometabolic removal of TCE. Among the three primary carbon sources studied, the presence of phenol provided the best cometabolic removal of TCE. When the concentration of carbon source was 3 mg-C/L, the initial TCE removal rates initiated by methane, toluene, and phenol utilizers were 1.5, 30, and 100 μg/L-hr, respectively. During the incubation period of 80 hours, TCE removal efficiencies were 26% and 96% with the presence of methane and toluene, respectively. However, it was 100% within 20 hours with the presence of phenol. For phenol utilizers, the initial TCE removal rates were about the same, when the phenol concentrations were 1.35, 2.7, and 4.5 mg/L. However, TCE removal was not proportional to the concentrations of phenol. TCE removal was hindered when the phenol concentration was higher than 4.5 mg/L because of the rapid depletion of dissolved oxygen. The presence of toluene also initiated cometabolic removal of TCE. The presence of toluene at 3 and 5 mg/L resulted in similar TCE removal. The initial TCE removal rate was about 95 μg/L-hr at toluene concentrations of 3 and 5 mg/L compared to 20 μg/L-hr at toluene concentration of 1 mg/L.

Sign in / Sign up

Export Citation Format

Share Document