Evaluation of Diallyl Phthalate Biodegradation Mechanisms in the Treatment of Synthetic Wastewater

Lead contaminated wastewater negatively impacts to living organisms as well as humans. In recent years, a highly promising biological process using the anaerobic production of sulfide ions by sulfate-reducing bacteria has presented itself as an alternative option for the removal of lead. This process is based on microbial utilization of electron donors, such as organic compounds (carbon sources), and sulfate as the terminal electron acceptor for sulfide production. The biogenic hydrogen sulfide reacts with dissolved heavy metals to form insoluble metal sulfide precipitates Removal of lead by an enriched consortium of sulfate-reducing bacteria (DM10) was evaluated sulfate reduction, sulfide production and lead precipitation. Four parallel anaerobic continuous stirred tank reactors (CSTR, V = 2L) (referred as R1 - R4) were fed with synthetic wastewater containing Pb2+ in the concentrations of 0, 100, 150 and 200 mg L-1 of lead and operated with a hydraulic retention time of 5 days for 40 days. The loading rates of each metal in R1- R4 were 0, 20, 30 and 40 mg L-1 d-1, respectively. The results showed that there was no inhibition of SRB growth and that lead removal efficiencies of 99-100% for Pb2+ were achieved in R2 (100 mg L-1) and R3 (150 mg L-1) throughout the experiment. For the highest lead concentration of 200 mg L-1, a decrease in efficiency of removal (from 100 to 96%) was observed at the end of the experiment. The obtained result of this study might help for a better control operation and performance improvements of reactors.

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CHARACTERISTICS OF NUTRIENT REMOVAL FROM SYNTHETIC WASTEWATER WITH DIFFERENT ORGANIC SUBSTRATES

Environmental Engineering and Management Journal ◽

10.30638/eemj.2011.088 ◽

2011 ◽

Vol 10 (5) ◽

pp. 649-654

Author(s):

Guangxue Wu ◽

Yuntao Guan ◽

Xinmin Zhan

Keyword(s):

Nutrient Removal ◽

Synthetic Wastewater ◽

Organic Substrates

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OPTIMIZATION OF ISES FOR SIMULTANEOUS NH4+, NO3 AND NO2 MONITORING IN SYNTHETIC WASTEWATER USING SOLVER

Environmental Engineering and Management Journal ◽

10.30638/eemj.2015.076 ◽

2015 ◽

Vol 14 (3) ◽

pp. 681-688

Author(s):

Milan Sak-Bosnar ◽

Natalija Velic ◽

Olivera Galovic ◽

Tonci Rezic ◽

Bozidar Santek ◽

...

Keyword(s):

Synthetic Wastewater

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OPTIMIZATION OF PHOSPHATE REMOVAL FROM SYNTHETIC WASTEWATER BY BACTERIAL CONSORTIUM USING BOX-BEHNKEN DESIGN

Environmental Engineering and Management Journal ◽

10.30638/eemj.2013.289 ◽

2013 ◽

Vol 12 (12) ◽

pp. 2371-2383

Author(s):

Krishnaswamy Usharani ◽

Perumalsamy Lakshmanaperumalsamy ◽

Muthusamy Muthukumar

Keyword(s):

Bacterial Consortium ◽

Phosphate Removal ◽

Synthetic Wastewater ◽

Box Behnken Design

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Nitrogen Removal in a Real-Time Controlled Sequencing Batch Membrane Bioreactor

Water Practice & Technology ◽

10.2166/wpt.2010.065 ◽

2010 ◽

Vol 5 (3) ◽

Author(s):

Cheng-Nan Chang ◽

Li-Ling Lee ◽

Han-Hsien Huang ◽

Ying-Chih Chiu

Keyword(s):

Real Time ◽

Nitrogen Removal ◽

Membrane Bioreactor ◽

Synthetic Wastewater ◽

Real Time Control ◽

Time Control ◽

Cake Layer ◽

On Line ◽

Solid Liquid ◽

Solid Liquid Separation

The performance of a real-time controlled Sequencing Batch Membrane Bioreactor (SBMBR) for removing organic matter and nitrogen from synthetic wastewater has been investigated in this study under two specific ammonia loadings of 0.0086 and 0.0045g NH4+-N gVSS−1 day−1. Laboratory results indicate that both COD and DOC removal are greater than 97.5% (w/w) but the major benefit of using membrane for solid-liquid separation is that the effluent can be decanted through the membrane while aeration is continued during the draw stage. With a continued aeration, the sludge cake layer is prevented from forming thus alleviating the membrane clogging problem in addition to significant nitrification activities observed in the draw stage. With adequate aeration in the oxic stage, the nitrogen removal efficiency exceeding 99% can be achieved with the SBMBR system. Furthermore, the SBMBR system has also been used to study the occurrence of ammonia valley and nitrate knee that can be used for real-time control of the biological process. Under appropriate ammonia loading rates, applicable ammonia valley and nitrate knee are detected. The real-time control of the SBMBR can be performed based on on-line ORP and pH measurements.

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Upgrading Wastewater Treatment by Water Hyacinth in Developing Countries

Water Science & Technology ◽

10.2166/wst.1990.0241 ◽

1990 ◽

Vol 22 (7-8) ◽

pp. 153-160 ◽

Cited By ~ 3

Author(s):

Pradeep Kumar ◽

R. J. Garde

Keyword(s):

Wastewater Treatment ◽

Water Hyacinth ◽

Treatment Plant ◽

Cod Removal ◽

Treatment System ◽

Synthetic Wastewater ◽

Second Phase ◽

Treatment Unit ◽

Batch Studies ◽

New Treatment

With increasing stress on existing wastewater treatment systems, it is necessary either to upgrade the treatment unit(s) or install an entirely new treatment plant. Obviously, the upgrading is preferred over the alternative of having a new system. Keeping this in view, in the present project, an attempt has been made to explore the possibility of upgrading existing facultative ponds using water hyacinth. Bench-scale batch studies were designed to compare the performance of hyacinth treatment system with facultative ponds. Investigations were carried out with synthetic wastewater having COD in the range of 32.5-1090 mg/l. The efficiency of COD removal in water hyacinth ponds was 15-20 percent more than the facultative ponds. Based on the results, an empirical model has been proposed for COD removal kinetics. In the second phase of the project a hyacinth pond was continuously operated. BOD, COD, TS, TN, TP, pH, and DO were regularly monitored. However, the DO of the effluent from hyacinth treatment system was considerably reduced. Effluent should be aerated before it is discharged. The results indicate that the existing facultative ponds can be stalked with water hyacinth to improve their performance as well as hyacinth treatment systems can be installed to support the conventional treatment.

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Influence of Daily Variation of Flow and Pollution Load on the Performance of Submerged Anaerobic/Aerobic Biofilm System

Water Science & Technology ◽

10.2166/wst.1990.0196 ◽

1990 ◽

Vol 22 (3-4) ◽

pp. 153-160 ◽

Cited By ~ 2

Author(s):

T. Okubo ◽

M. Okada ◽

A. Murakami ◽

Y. Inamori

Keyword(s):

Organic Carbon ◽

Field Study ◽

Laboratory Study ◽

Hydraulic Retention Time ◽

Daily Variation ◽

Synthetic Wastewater ◽

Constant Flow ◽

Pollution Load ◽

Mean Values ◽

Anaerobic Filter

Effects of daily variation of flow on the performance of submerged anaerobic/aerobic biofilm systems were investigated both by laboratory study using synthetic wastewater and by field study using gray water. In laboratory study, concentration of dissolved organic carbon (DOC) in effluent from anaerobic filter fluctuated with daily variation of flow when average hydraulic retention time (HRT) was below 10 h. However, daily mean values of DOC under the varied flow was almost the same as those under constant flow within the same daily mean HRT. Aerobic filter linked to anaerobic filter reduced the concentration of DOC satisfactorily though the concentration in anaerobic filter increased under short HRT. In field study, percent removal of organic carbon by anaerobic filter was considerably smaller (20-30%) than that in laboratory study (90-95%) both at HRT of 20 h though it was improved up to 60-80% by aerobic filter. Effects of peaking factor of flow on the variation of DOC were evaluated by mathematical analysis. It seemed that the peaking factor hardly affected daily mean values of DOC within the same daily mean HRT though maximum values of DOC increased with the increase of peaking factor.

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Dynamic changes in spatial microbial distribution in mixed-population biofilms: experimental results and model simulation

Water Science & Technology ◽

10.2166/wst.1995.0266 ◽

1995 ◽

Vol 32 (8) ◽

pp. 67-74 ◽

Cited By ~ 20

Author(s):

Satoshi Okabe ◽

Kikuko Hirata ◽

Yoshimasa Watanabe

Keyword(s):

Oxygen Diffusion ◽

Loading Rate ◽

Model Simulation ◽

Mixed Population ◽

Experimental Results ◽

Synthetic Wastewater ◽

Diffusion Limitation ◽

Dynamic Changes ◽

Microbial Distribution ◽

Rotating Biological Contactors

Dynamic changes in spatial microbial distribution in mixed-population biofilms were experimentally determined using a microslicer technique and simulated by a biofilm accumulation model (BAM). Experimental results were compared with the model simulation. The biofilms cultured in partially submerged rotating biological contactors (RBC) with synthetic wastewater were used as test materials. Experimental results showed that an increase of substrate loading rate (i.e., organic carbon and NH4-N) resulted in the microbial stratification in the biofilms. Heterotrophs defeated nitrifiers and dominated in the outer biofilm, whereas nitrifiers were diluted out in the outer biofilm and forced into the inner biofilm. At higher organic loading rates, a stronger stratified microbial spatial distribution was observed, which imposed a severe internal oxygen diffusion limitation on nitrifiers and resulted in the deterioration of nitrification efficiency. Model simulations described a general trend of the stratified biofilm structure. However, the actual stratification was stronger than the simulated results. For implication in the reactor design, when the specific carbon loading rate exceeds a certain limit, nitrification will be deteriorated or require a long start-up period due to the interspecies competition resulting in oxygen diffusion limitation. The extend of microbial stratification in the biofilm is especially important for determination of feasibility of nitrification in the presence of organic matters.

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Hydrolysis of organic wastewater particles in laboratory scale and pilot scale biofilm reactors under anoxic and aerobic conditions

Water Science & Technology ◽

10.2166/wst.1998.0805 ◽

1998 ◽

Vol 38 (8-9) ◽

pp. 179-188 ◽

Cited By ~ 4

Author(s):

K. F. Janning ◽

X. Le Tallec ◽

P. Harremoës

Keyword(s):

Organic Matter ◽

Mass Balance ◽

Particulate Organic Matter ◽

Removal Rate ◽

Pilot Scale ◽

Laboratory Scale ◽

Synthetic Wastewater ◽

Aerobic Conditions ◽

Biofilm Reactors ◽

Hydrolysis Of

Hydrolysis and degradation of particulate organic matter has been isolated and investigated in laboratory scale and pilot scale biofilters. Wastewater was supplied to biofilm reactors in order to accumulate particulates from wastewater in the filter. When synthetic wastewater with no organic matter was supplied to the reactors, hydrolysis of the particulates was the only process occurring. Results from the laboratory scale experiments under aerobic conditions with pre-settled wastewater show that the initial removal rate is high: rV, O2 = 2.1 kg O2/(m3 d) though fast declining towards a much slower rate. A mass balance of carbon (TOC/TIC) shows that only 10% of the accumulated TOC was transformed to TIC during the 12 hour long experiment. The pilot scale hydrolysis experiment was performed in a new type of biofilm reactor - the B2A® biofilter that is characterised by a series of decreasing sized granular media (80-2.5 mm). When hydrolysis experiments were performed on the anoxic pilot biofilter with pre-screened wastewater particulates as carbon source, a rapid (rV, NO3=0.7 kg NO3-N/(m3 d)) and a slowler (rV, NO3 = 0.3 kg NO3-N/(m3 d)) removal rate were observed at an oxygen concentration of 3.5 mg O2/l. It was found that the pilot biofilter could retain significant amounts of particulate organic matter, reducing the porosity of the filter media of an average from 0.35 to 0.11. A mass balance of carbon shows that up to 40% of the total incoming TOC accumulates in the filter at high flow rates. Only up to 15% of the accumulated TOC was transformed to TIC during the 24 hour long experiment.

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