Comparative investigations on COD-removal in sequencing batch reactors and continuous flow plants

2001 ◽  
Vol 43 (3) ◽  
pp. 45-52 ◽  
Author(s):  
T. Dockhorn ◽  
N. Dichtl ◽  
R. Kayser
Keyword(s):  
Removal Efficiency ◽  
Municipal Wastewater ◽  
Plug Flow ◽  
Main Idea ◽  
Operating Conditions ◽  
Cod Removal ◽  
Batch Reactors ◽  
Mixing Characteristics ◽  
Hydraulic Load ◽  
The Individual

Investigations on enhanced COD removal from municipal wastewater were performed over a period of 2.5 years, comparing three different types of reactor. The main idea was to determine the influence of the mixing characteristics of the reactor on the treatment processes and the effluent quality. Therefore three pilot plants (a completely mixed reactor, a cascade of three reactors and a SBR) were operated under equal conditions (wastewater, hydraulic load, temperature, sludge age) in parallel to each other. Investigations were carried out at different sludge ages. It could be shown that within one sludge age the CODf removal efficiency increased, when mixing characteristics came closer to the plug flow and it also increased with higher temperatures. A significant correlation was observed between the COD removal efficiency and the sludge load. The higher the sludge load was the greater the CODf concentration in the effluent. Especially the SBR reactor showed an excellent performance under the given operating conditions. Dynamic simulation calculations were carried out, to investigate whether the influence of the type of reactor on the COD-elimination could be described theoretically by combining growth kinetics and the mixing characteristics of the individual reactors. The results showed that performance was better when mixing characteristics came closer to plug flow.

scholarly journals Toward Optimization of Wood Industry Wastewater Treatment in Microbial Fuel Cells—Mixed Wastewaters Approach

Energies ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 263 ◽  
Author(s):  
Monika Kloch ◽  
Renata Toczyłowska-Mamińska
Keyword(s):  
Wastewater Treatment ◽  
Removal Efficiency ◽  
Municipal Wastewater ◽  
Power Production ◽  
Cod Removal ◽  
Treatment Efficiency ◽  
External Resistance ◽  
Wood Industry ◽  
Cod Removal Efficiency ◽  
Industry Wastewater

Microbial fuel cell (MFC) has the potential to become a promising sustainable technology of wastewater treatment. Usually, the investigations on MFCs are aimed at maximized power production in the system. In this article, we focused on the optimization of wood industry wastewater treatment in MFC, in combination with municipal wastewater as a source of microorganisms. We investigated the influence of different external resistance (2000 Ω, 1000 Ω, 500 Ω, and 100 Ω) on power density and wastewater treatment efficiency (chemical oxygen demand (COD) removal) in 1-month MFC operation time. We found that the highest COD removal was for MFCs under R = 1000 Ω after 22 days of MFC operation, while the highest current density was obtained for the lowest applied resistance. The results imply that wastewater treatment parameters such as resistance and time of MFC operation should be a subject of optimization for each specific type of wastewater used, in order to maximize either wastewater treatment efficiency or power production in MFC. Thus, optimization of power production and COD removal efficiency in MFCs need to be run separately as different resistances are required for maximizing these two parameters. When COD removal efficiency is a subject of optimization, there is no universal value of external resistance, but it should be set to the specific wastewater characteristics.

The Pulse Electrolysis Treatment of Waste Emulsion Orthogonal Experimental Study

2013 ◽  
Vol 303-306 ◽  
pp. 2616-2619
Author(s):  
Xiao Yan Sun ◽  
Pei Dao Pan ◽  
Jang Jie Wang
Keyword(s):  
Experimental Study ◽  
Removal Efficiency ◽  
Current Density ◽  
Pulse Width ◽  
Ph Value ◽  
Operating Conditions ◽  
Cod Removal ◽  
Pulse Electrolysis ◽  
Cod Removal Efficiency ◽  
Plate Distance

This mechanical processing waste emulsion for the study, handled by pulse electrolysis. Arrangements by orthogonal testing, experimental study on plate distance (d), current density (i), the pH value and the pulse width (tP) impact on COD removal efficiency, very poor analysis of test data to determine various factors affecting the COD removal efficiency of primary and secondary sort: pH value > current density > pulse width > plate distance, optimal operating conditions. Orthogonal experimental data derived from regression analysis, determination of cross of quadratic polynomial regression equations, mathematical model. Tests confirmed that pulse electrochemical method for treatment of waste emulsion with low energy consumption, short response time, and other advantages, strong applicability of wastewater, building mathematical models, providing theoretical basis for subsequent design.

scholarly journals Co-treatment of old landfill leachate and municipal wastewater in sequencing batch reactor (SBR): effect of landfill leachate concentration

2016 ◽  
Vol 51 (4) ◽  
pp. 377-387 ◽  
Author(s):  
Kshitij Ranjan ◽  
Shubhrasekhar Chakraborty ◽  
Mohini Verma ◽  
Jawed Iqbal ◽  
R. Naresh Kumar
Keyword(s):  
Removal Efficiency ◽  
Landfill Leachate ◽  
Suspended Solids ◽  
Sequencing Batch Reactor ◽  
Municipal Wastewater ◽  
Batch Reactor ◽  
Operating Conditions ◽  
Volume Index ◽  
Turbidity Removal ◽  
Mixed Liquor

Sequencing batch reactor (SBR) was assessed for direct co-treatment of old landfill leachate and municipal wastewater for chemical oxygen demand (COD), nutrients and turbidity removal. Nitrogen removal was achieved by sequential nitrification and denitrification under post-anoxic conditions. Initially, SBR operating conditions were optimized by varying hydraulic retention time (HRT) at 20% (v/v) landfill leachate concentration, and results showed that 6 d HRT was suitable for co-treatment. SBR performance was assessed in terms of COD, ammonia, nitrate, phosphate, and turbidity removal efficiency. pH, mixed liquor suspended solids, mixed liquor volatile suspended solids (MLVSS), and sludge volume index were monitored to evaluate stability of SBR. MLVSS indicated that biomass was able to grow even at higher concentrations of old landfill leachate. Ammonia and nitrate removal efficiency was more than 93% and 83%, respectively, whereas COD reduction was in the range of 60–70%. Phosphate and turbidity removal efficiency was 80% and 83%, respectively. Microbial growth kinetic parameters indicated that there was no inhibition of biomass growth up to 20% landfill leachate. The results highlighted that SBR can be used as an initial step for direct co-treatment of landfill leachate and municipal wastewater.

Anaerobic treatment of sulfate-containing municipal wastewater with a fluidized bed reactor at 20 °C

2016 ◽  
Vol 73 (10) ◽  
pp. 2446-2452 ◽  
Author(s):  
B. Düppenbecker ◽  
P. Cornel
Keyword(s):  
Fluidized Bed ◽  
Removal Efficiency ◽  
Municipal Wastewater ◽  
Oxygen Demand ◽  
Fluidized Bed Reactor ◽  
Anaerobic Treatment ◽  
Cod Removal ◽  
Sulfate Reducing ◽  
Mass Flows ◽  
Reducing Bacteria

This study focuses on the anaerobic treatment of sulfate-containing municipal wastewater at 20 °C with a fluidized bed reactor. Mean influent chemical oxygen demand (COD) and sulfate concentrations were 481 and 96 mg/l. The response of the COD removal efficiency to increasing organic loading rates (OLR) was investigated. Average total COD removal was 61% at OLR between 2.7 and 13.7 kg COD/(m³·d) and did not distinctly depend on the OLR. To assess the removal efficiency in more detail the COD in- and output mass flows were balanced. The results showed that only 11–12% of the input COD was recovered as gaseous methane. About 12–13% of the input COD remained in the effluent as dissolved methane. Furthermore, a distinct amount of 12–19% of the input COD remained in the reactor as settled sludge and was not further biologically degraded. Due to the reduction by sulfate-reducing bacteria, 13–14% of the input COD was degraded. Further adverse impacts of the influent sulfate on the anaerobic treatment process are discussed as well.

Phenol degradation in horizontal-flow anaerobic immobilized biomass (HAIB) reactor under mesophilic conditions

2001 ◽  
Vol 44 (4) ◽  
pp. 167-174 ◽  
Author(s):  
R. M.L. Bolaños ◽  
M. B.A. Varesche ◽  
M. Zaiat ◽  
E. Foresti
Keyword(s):  
Removal Efficiency ◽  
Phenol Degradation ◽  
Oxygen Demand ◽  
Operating Conditions ◽  
Cod Removal ◽  
Horizontal Flow ◽  
Anaerobic Sludge ◽  
Cod Removal Efficiency ◽  
Immobilized Biomass ◽  
Potential Use

A bench-scale horizontal-flow anaerobic immobilized biomass (HAIB) reactor was assayed aiming to verify its potential use for phenol degradation. The HAIB reactor consisted of a bore-silicate tube (100 cm long; 5.04 cm diameter) filled with polyurethane foam matrices containing immobilized anaerobic sludge. Before being subjected to phenol, the reactor was fed with synthetic substrate at the influent chemical oxygen demand (COD) of 1,028 mg.l−1 achieving 98% of COD removal efficiency. Thereafter, phenol as the sole carbon source was added under step-increasing concentrations from 50 to 1,200 mg.l−1. Phenol degradation was evaluated by gas chromatographic analysis of influent and effluent samples. Process monitoring included determinations of pH, volatile acids, alkalinity and COD. The HAIB reactor was operated at a constant hydraulic detention time (HDT) of 12 hours. After 33 days with 50 mg/l of phenol in the influent, the reactor achieved 98% of COD removal efficiency. Successful phenol degradation (efficiency removal of 99%) occurred for influent concentrations of 100, 300, 600, 900 and 1,200 mg.l−1 after 148, 58, 47, 29 and 7 days, respectively. The predominance of Methanosaeta-like, rods and methanogenic cocci could be observed in all the operating conditions, besides the presence of phenol oxidizing microorganisms as irregular rods. The results indicate that phenol degradation at very high rates can be accomplished in HAIB reactors containing acclimatized biomass.

The effect of operational conditions on the performance of UASB reactors for domestic wastewater treatment

2005 ◽  
Vol 52 (1-2) ◽  
pp. 299-305 ◽  
Author(s):  
R.C. Leitão ◽  
J.A. Silva-Filho ◽  
W. Sanders ◽  
A.C. van Haandel ◽  
G. Zeeman ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Municipal Wastewater ◽  
Domestic Wastewater ◽  
Pilot Scale ◽  
Cod Removal ◽  
Upflow Anaerobic Sludge Blanket ◽  
Anaerobic Sludge ◽  
Operational Conditions ◽  
Cod Removal Efficiency ◽  
Uasb Reactors

In this investigation, the performance of Upflow Anaerobic Sludge Blanket (UASB) reactors treating municipal wastewater was evaluated on the basis of: (i) COD removal efficiency, (ii) effluent variability, and (iii) pH stability. The experiments were performed using 8 pilot-scale UASB reactors (120 L) from which some of them were operated with different influent COD (CODInf ranging from 92 to 816 mg/L) and some at different hydraulic retention time (HRT ranging from 1 to 6 h). The results show that decreasing the CODInf, or lowering the HRT, leads to decreased efficiencies and increased effluent variability. During this experiment, the reactors could treat efficiently sewage with concentration as low as 200 mg COD/L. They could also be operated satisfactorily at an HRT as low as 2 hours, without problems of operational stability. The maximum COD removal efficiency can be achieved at CODInf exceeding 300 mg/L and HRT of 6 h.

scholarly journals Biological decolorization of reactive azo dye by anaerobic/aerobic-sequencing batch reactor system

2015 ◽  
Vol 17 (1) ◽  
pp. 210-219 ◽  
Keyword(s):  
Removal Efficiency ◽  
Azo Dye ◽  
Dye Removal ◽  
Batch Reactor ◽  
Cod Removal ◽  
Organic Loading Rate ◽  
Batch Reactors ◽  
System P ◽  
Removal Efficiencies ◽  
Initial Color

<div> <p>This study aims to investigate the removal of a reactive azo dye (Reactive Red 198) in anaerobic/aerobic sequencing batch reactors (SBR). The total volume of the SBR system used in the study was 10 l. Sludge age was selected as 15 days. The color removal efficiencies varied between 76 to 98% with initial color concentrations of about 20 and 50 mg l<sup>-1</sup>. The effluent color concentration changed between 0.4-6.0 mg l<sup>-1</sup>. The maximum dye removal efficiencies of the SBR system under 20 mg l<sup>-1</sup> dye concentration with 16/4 hours anaerobic/aerobic phases respectively were %98. The increase of anaerobic contact times had improved dye removal efficiency. The COD removal was also high during this period (81-94 %). The increase of organic loading rate from 500 to 1000 mg COD l<sup>-1</sup> day<sup>-1</sup> had improved the dye removal efficiency (from 88% to 96%) but deteriorated the COD removal efficiency to 81% from 88% in SBR systems.</p> </div> <p>&nbsp;</p>

Treatment of synthetic kraft evaporator condensate using thermophilic and mesophilic membrane aerated biofilm reactors

2010 ◽  
Vol 61 (7) ◽  
pp. 1749-1756 ◽  
Author(s):  
B. Q. Liao ◽  
M. R. Zheng ◽  
L. Ratana-Rueangsri
Keyword(s):  
Comparative Study ◽  
Chemical Oxygen Demand ◽  
Removal Efficiency ◽  
Oxygen Demand ◽  
Cod Removal ◽  
Batch Reactors ◽  
Sequencing Batch Reactors ◽  
Biofilm Reactors ◽  
Cod Removal Efficiency

A comparative study on the treatment of synthetic kraft evaporator condensate was conducted using thermophilic (55°C) and mesophilic (30°C) membrane aerated biofilm reactors (MABRs) and sequencing batch reactors (SBRs) for 8 months. Under tested conditions, a chemical oxygen demand (COD) removal efficiency of 80–95% was achieved with both thermophilic and mesophilic MABRs and SBRs. The COD removal efficiency of thermophilic MABR (80–90%) was slightly lower than that of the mesophilic MABR (85–95%) and the thermophilic SBR (90–95%). A significant amount (13–37%) of COD was stripped by conventional aeration in the SBRs, while stripping in MABRs was negligible. Simultaneous COD removal and denitrification were observed in the mesophilic MABR, while the thermophilic MABR contributed mainly for COD removal. Nitrification was not significant in both the thermophilic and mesophilic MABRs. The results suggest that treatment of kraft evaporator condensate is feasible with the use of both thermophilic and mesophilic MABRs in terms of COD removal with the advantages of negligible stripping.

scholarly journals Effects of azo dye on simultaneous biological removal of azo dye and nutrients in wastewater

2018 ◽  
Vol 5 (8) ◽  
pp. 180795 ◽  
Author(s):  
Aihui Chen ◽  
Bairen Yang ◽  
Yuanqiang Zhou ◽  
Yuze Sun ◽  
Cheng Ding
Keyword(s):  
Removal Efficiency ◽  
Azo Dye ◽  
Oxygen Demand ◽  
Cod Removal ◽  
Batch Reactors ◽  
Biological Removal ◽  
Oxidation Reduction ◽  
Alizarin Yellow ◽  
Oxidation Reduction Potential ◽  
Alizarin Yellow R

The potential disrupting effects of Azo dye on wastewater nutrients removal deserved more analysis. In this study, 15 days exposure experiments were conducted with alizarin yellow R (AYR) as a model dye to determine whether the dye caused adverse effects on biological removal of both the dye and nutrients in acclimated anaerobic–aerobic–anoxic sequencing batch reactors. The results showed that the AYR removal efficiency was, respectively, 85.7% and 66.8% at AYR concentrations of 50 and 200 mg l −1 , while higher AYR inlet (400 mg l −1 ) might inactivate sludge. Lower removal of AYR at 200 mg l −1 of AYR was due to the insufficient support of electron donors in the anaerobic process. However, the decolorized by-products p -phenylenediamine and 5-aminosalicylic were completely decomposed in the following aerobic stage at both 50 and 200 mg l −1 of AYR concentrations. Compared with the absence of AYR, the presence of 200 mg l −1 of AYR decreased the total nitrogen removal efficiency from 82.4 to 41.1%, and chemical oxygen demand (COD) removal efficiency initially decreased to 68.1% and then returned to around 83.4% in the long-term exposure time. It was also found that the inhibition of AYR, nitrogen and COD removal induced by a higher concentration of AYR was due to the increased intracellular reactive oxygen species production, which caused the rise of oxidation–reduction potential value and decreased ammonia monooxygenase and nitrite oxidoreductase activities.

Case study on the bioeffluent of petrochemical wastewater by electro-fenton method

1999 ◽  
Vol 39 (10-11) ◽  
pp. 145-149 ◽  
Author(s):  
Yao-Hui Huang ◽  
Shanshan Chou ◽  
Ming-Ging Perng ◽  
Gaw-Hao Huang ◽  
Sheng-Shung Cheng
Keyword(s):  
Removal Efficiency ◽  
Sodium Hypochlorite ◽  
Operating Conditions ◽  
Cod Removal ◽  
The Other ◽  
Ferrous Ion ◽  
Screening Tests ◽  
Fenton Process ◽  
Petrochemical Wastewater

The electro-Fenton method, in which ferrous ion is produced at the anode and used as a catalyst of H2O2, was applied for treating the bioeffluent of petrochemical manufacturing wastewater. The major pollutant in the bioeffluent was identified as hexamine, which was nonbiodegradable and contributed 65% of COD. The goal of this study was to treat the biotreatment effluent with more than 50% of COD removal efficiency. Oxidants that involved ozone, ozone/H2O2, sodium hypochlorite, and Fenton's reagent were employed to treat this effluent by jar tests. However, none could meet the goal in the range of operating conditions used. On the other hand, more than 80% of COD was removed with the electro-Fenton process. These screening tests indicated that only the electro-Fenton process was compatible with the goal.

Sign in / Sign up

Export Citation Format

Share Document