Effect of constructed wetland system on aquaculture wastewater by ecological treatment

In this study, an integrated ecological system was constructed to treat small scattered aquaculture wastewater in southern rural areas of China. The water outlet of 4 level wetlands was continuously monitored from July to December in 2017. Results showed the average concentrations of total nitrogen (TN), ammonia nitrogen (NH4+-N), nitrate nitrogen (NO3-N), total phosphorus (TP) and chemical oxygen demand (COD) were 43.64mg/L, 17.53mg/L, 1.71mg/L, 1.66mg/L and 51.39mg/L in the average effluent concentration of grade I wetland, respectively, and 8.35mg/L, 4.42mg/L, 0.24mg/L, 0.26mg/L, 21.32mg/L in the average effluent concentration of grade IV wetland, respectively. The removal rates were 81%, 75%, 86%, 85% and 59% for TN, NH4+-N, NO3-N, TP and COD in the integrated ecological system, respectively. The effluents from the integrated ecological system met the requirements of “Discharge Standard of Pollutants for Livestock and Poultry Breeding” (GB 18596-2001) and achieved “Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant” (GB 18918-2002) the center two levels to discharge the standard. Obviously, the integrated ecological system could work efficiently in treating the rural scattered aquaculture wastewater, and also possess merits of low construction and operation costs and simple management method, which will be benefited to its application in the southern rural regions of China.

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Experimental Study on Modified Fly Ash as a Substrate of Constructed Wetland

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.675-677.524 ◽

2014 ◽

Vol 675-677 ◽

pp. 524-529 ◽

Cited By ~ 1

Author(s):

Meng Fei Guo ◽

Ping Xian ◽

Xi Liu ◽

Long Hui Yang ◽

Long Hui Zhan ◽

...

Keyword(s):

Wastewater Treatment ◽

Fly Ash ◽

Municipal Wastewater ◽

Removal Rate ◽

Treatment Plant ◽

Ammonia Nitrogen ◽

Municipal Wastewater Treatment ◽

Effluent Concentration ◽

Standard Level ◽

Priority Standard

In order to develop a new substrate filler for wetland, Fly ash and soil was mixed and modified in different mass ratio, then, static adsorption and seepage purification experiments were carried out to choose four appropriate modified fillers for wetland model experiment. Experimental results showed that when the mass proportion of fly ash and soil was 3:7, the best treatment effect was achieved. While using this modified wetland for wastewater treatment, the removal rate of total nitrogen (TN), total phosphorus (TP), ammonia nitrogen (NH4-N) and COD was 57.52%, 97.58%, 93.78% and 89.53% respectively. The effluent concentration of TN could meet the priority standard (level B) of Discharge standard of pollutants for municipal wastewater treatment plant (GB18918-2002), while the effluent concentration of TP, NH4-N and COD could meet the priority standard (level A).

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Tertiary nitrification in pure oxygen moving bed biofilm reactors

Water Science & Technology ◽

10.2166/wst.2000.0467 ◽

2000 ◽

Vol 41 (4-5) ◽

pp. 361-368 ◽

Cited By ~ 1

Author(s):

L. Bonomo ◽

G. Pastorelli ◽

E. Quinto ◽

G. Rinaldi

Keyword(s):

Municipal Wastewater ◽

Treatment Plant ◽

Ammonia Nitrogen ◽

Pure Oxygen ◽

Secondary Effluent ◽

Municipal Wastewater Treatment ◽

Typical Application ◽

Moving Bed ◽

Biofilm Reactors ◽

Nitrogen Ratio

Two bench-scale reactors, fed with the secondary effluent of a municipal wastewater treatment plant (WWTP), were used in order to study tertiary nitrification in pure oxygen moving bed biofilm reactors (PO-MBBRs) with patented KMT® media as biofilm carriers. The process allowed to measure very high nitrification rates, both in ammonia limiting conditions (up to 7 gN m−2 d−1; oxygen-to-ammonia nitrogen ratio higher than 3–4 mgO2 (mgN)−1) and in oxygen limiting conditions (up to 8 gN m−2 d−1; oxygen-to-ammonia nitrogen ratio lower than 1–2 mgO2 (mgN)−1). Since the process proved flexible and reliable, it is suitable for full-scale application to municipal WWTPs. Typical application could regard, but is not limited to, tertiary nitrification of secondary effluent from existing high-purity oxygen activated sludge systems designed to achieve only organic carbon removal.

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Quantifying methane emissions from anaerobic digesters

Water Science & Technology ◽

10.2166/wst.2019.415 ◽

2019 ◽

Vol 80 (9) ◽

pp. 1654-1661

Author(s):

J. Tauber ◽

V. Parravicini ◽

K. Svardal ◽

J. Krampe

Keyword(s):

Municipal Wastewater ◽

Treatment Plant ◽

Oxygen Demand ◽

Methane Emissions ◽

Gas Production ◽

Gas Chromatography Mass Spectrometry ◽

Municipal Wastewater Treatment ◽

Flux Chamber ◽

Batch Tests ◽

Residual Gas

Abstract In this research, sources of methane emissions of an anaerobic digester (AD) system at a municipal wastewater treatment plant (WWTP) with 260,000 population equivalent (PE) capacity were detected by a non-dispersive infrared (NDIR) camera. The located emissions were evaluated qualitatively and were documented with photographs and video films. Subsequently, the emission sources were quantified individually using different methods like the Flux-Chamber method and sampling from the digester's circulation pipe. The dissolved methane in the sludge digester was measured via gas chromatography-mass spectrometry (GC-MS) and 6.8% oversaturation compared to the equilibrium after Henry's law was found. Additionally, the residual gas potential of the digestate was measured using batch tests with 10 days' additional stabilisation time. The PE-specific residual gas production of the full-scale AD was calculated to 12.4 g CH4/(PE · y). An extended chemical oxygen demand (COD) balance including methane emissions for the whole digester system was calculated. Also the measured methane loads were calculated and summed up. The total methane loss of the AD was calculated at 24.6 g CH4/(PE · y), which corresponds to 0.4% of the produced biogas (4,913 g CH4/(PE · y)). PE-specific methane emission factors are presented for each investigated (point) source like the sludge outlet at the digester's head, a leaking manhole sealing and cracks in the concrete structure.

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Initiating Biodegradation of Polyvinylpyrrolidone in an Aqueous Aerobic Environment: Technical Note / Zainicjowanie Biodegradacji Poliwinylopirolidonu W Środowisku Wodno-Tlenowym: Notatki Techniczne

Ecological Chemistry and Engineering S ◽

10.2478/eces-2013-0015 ◽

2013 ◽

Vol 20 (1) ◽

pp. 199-208 ◽

Cited By ~ 2

Author(s):

Marketa Julinova ◽

Jan Kupec ◽

Roman Slavik ◽

Maria Vaskova

Keyword(s):

Wastewater Treatment ◽

Activated Sludge ◽

Municipal Wastewater ◽

Waste Treatment ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Oxygen Demand ◽

Technical Note ◽

Aerobic Biodegradation ◽

Municipal Wastewater Treatment

Abstract A synthetic polymer, polyvinylpyrrolidone (PVP - E 1201) primarily finds applications in the pharmaceutical and food industries due to its resistance and zero toxicity to organisms. After ingestion, the substance passes through the organism unchanged. Consequently, it enters the systems of municipal wastewater treatment plants (WWTP) without decomposing biologically during the waste treatment process, nor does it attach (through sorption) to particles of activated sludge to any significant extent, therefore, it passes through the system of a WWTP, which may cause the substance to accumulate in the natural environment. For this reason the paper investigates the potential to initiate aerobic biodegradation of PVP in the presence of activated sludge from a municipal wastewater treatment plant. The following agents were selected as the initiators of the biodegradation process - co-substrates: acrylamide, N-acethylphenylalanine and 1-methyl-2-pyrrolidone, a substance with a similar structure to PVP monomer. The biodegradability of PVP in the presence of co-substrates was evaluated on the basis of biological oxygen demand (BOD) as determined via a MicroOxymax O2/CO2/CH4 respirometer. The total substrate concentration in the suspension equaled 400 mg·dm-3, with the ratio between PVP and the cosubstrate being 1:1, while the concentration of the dry activated sludge was 500 mg·dm-3. Even though there was no occurrence of a significant increase in the biodegradation of PVP alone in the presence of a co-substrate, acrylamide appeared to be the most effective type of co-substrate. Nevertheless, a recorded decrease in the slope of biodegradation curves over time may indicate that a process of primary decomposition was underway, which involves the production of metabolites that inhibit activated sludge microorganisms. The resulting products are not identified at this stage of experimentation.

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Advanced nitrogen removal from municipal wastewater treatment plant secondary effluent using a deep bed denitrification filter

Water Science & Technology ◽

10.2166/wst.2018.231 ◽

2018 ◽

Vol 77 (11) ◽

pp. 2723-2732 ◽

Cited By ~ 12

Author(s):

Xiaowei Zheng ◽

Shenyao Zhang ◽

Jibiao Zhang ◽

Deying Huang ◽

Zheng Zheng

Keyword(s):

Wastewater Treatment ◽

Quartz Sand ◽

High Throughput Sequencing ◽

Municipal Wastewater ◽

Nitrate Nitrogen ◽

Treatment Plant ◽

Oxygen Demand ◽

Secondary Effluent ◽

Municipal Wastewater Treatment ◽

Microbial Distribution

Abstract With the improvement of wastewater discharge standards, wastewater treatment plants (WWTPs) are continually undergoing technological improvements to meet the evolving standards. In this study, a quartz sand deep bed denitrification filter (DBDF) was used to purify WWTP secondary effluent, utilizing high nitrate nitrogen concentrations and a low C/N ratio. Results show that more than 90% of nitrate nitrogen (NO3-N) and 75% of chemical oxygen demand (COD) could be removed by the 20th day of filtration. When the filter layer depth was set to 1,600 mm and the additional carbon source CH3OH was maintained at 30 mg L−1 COD (20 mg L−1 methanol), the total nitrogen (TN) and COD concentrations of DBDF effluent were stabilized below 5 and 30 mg L−1, respectively. Analysis of fluorescence revealed that DBDF had a stronger effect on the removal of dissolved organic matter (DOM), especially of aromatic protein-like substances. High throughput sequencing and qPCR results indicate a distinctly stratified microbial distribution for the main functional species in DBDF, with quartz sand providing a good environment for microbes. The phyla Proteobacteria, Bacteroidetes, and Chloroflexi were found to be the dominant species in DBDF.

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Application of anoxic phase in SBR reactor to increase the efficiency of ammonia removal in Vietnamese municipal WWTPs

E3S Web of Conferences ◽

10.1051/e3sconf/20199701017 ◽

2019 ◽

Vol 97 ◽

pp. 01017 ◽

Cited By ~ 4

Author(s):

Tran Ha Quan ◽

Elena Gogina

Keyword(s):

Wastewater Treatment ◽

Municipal Wastewater ◽

Rate Increase ◽

Treatment Plant ◽

Ammonia Nitrogen ◽

Ammonia Removal ◽

Biological Wastewater Treatment ◽

Municipal Wastewater Treatment ◽

Near Future ◽

Nitrogen Loadings

Process removal nutrients, especially nitrogen – ammonia in municipal wastewater treatment is a challenger of design and operate wastewater treatment plant. Nowadays in Vietnam, technology SBR has been wide applied in biological wastewater treatment but the concentration of nitrogen – ammonia in treated water cannot achieve the discharge standard. For the purpose to reach the Vietnamese Standard A, the modification of SBR has been added the anoxic phase into operated cycle to create the denitrification’s environment and enhance performance of ammonia – nitrogen removal in municipal wastewater treatment at present and in the near future. The results of experiment shows that, the efficiency of N – NH4 removal in reactors sustainable in range 75 – 80% with the nitrogen loadings rate from 0.07 – 0.25 kg N – NH4/kg sludge/d. However, in 3 hours of anoxic phase, the value of specific denitrification rate is 0.10 – 0.15 kg N – NO3/kg sludge/d with the organic loadings rate in range 0.3 – 1.0 kg BOD/kg sludge/d and can reach the maximum is 0.2 kg N – NO3/kg sludge/d when the organic loadings rate increase to 2.0 kg BOD/kg sludge/d.

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Integrated Membrane Process for the Treatment and Reuse of Residual Table Olive Fermentation Brine and Anaerobically Digested Sludge Centrate

Membranes ◽

10.3390/membranes10100253 ◽

2020 ◽

Vol 10 (10) ◽

pp. 253

Author(s):

Carlos Carbonell-Alcaina ◽

Jose Luis Soler-Cabezas ◽

Amparo Bes-Piá ◽

María Cinta Vincent-Vela ◽

Jose Antonio Mendoza-Roca ◽

...

Keyword(s):

Organic Matter ◽

Municipal Wastewater ◽

Forward Osmosis ◽

Treatment Plant ◽

Oxygen Demand ◽

Transmembrane Pressure ◽

Municipal Wastewater Treatment ◽

Digested Sludge ◽

Anaerobically Digested Sludge ◽

Table Olive

Management of wastewater is a major challenge nowadays, due to increasing water demand, growing population and more stringent regulations on water quality. Wastewaters from food conservation are especially difficult to treat, since they have high salinity and high organic matter concentration. The aim of this work is the treatment of the effluent from a table olive fermentation process (FTOP) with the aim of reusing it once the organic matter is separated. The process proposed in this work consists of the following membrane-based technologies: Ultrafiltration (UF) (UP005, Microdyn Nadir), Forward Osmosis (FO) (Osmen2521, Hydration Technology Innovation) and Nanofiltration (NF) (NF245, Dow). The FO process was implemented to reduce the salinity entering the NF process, using the FTOP as draw solution and, at the same time, to concentrate the centrate produced in the sludge treatment of a municipal wastewater treatment plant with the aim of obtaining a stream enriched in nutrients. The UF step achieved the elimination of 50% of the chemical oxygen demand of the FTOP. The UF permeate was pumped to the FO system reducing the volume of the anaerobically digested sludge centrate (ADSC) by a factor of 3 in 6.5 h. Finally, the ultrafiltrated FTOP diluted by FO was subjected to NF. The transmembrane pressure needed in the NF stage was 40% lower than that required if the ultrafiltration permeate was directly nanofiltered. By means of the integrated process, the concentration of organic matter and phenolic compounds in the FTOP decreased by 97%. Therefore, the proposed process was able to obtain a treated brine that could be reused in other processes and simultaneously to concentrate a stream, such as the ADSC.

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Technical and experimental evaluation of an innovative decentralized technology for the municipal wastewater treatment in the city of Rome

Water Science & Technology ◽

10.2166/wst.2010.332 ◽

2010 ◽

Vol 62 (4) ◽

pp. 956-962 ◽

Cited By ~ 1

Author(s):

Agostina Chiavola ◽

Piero Sirini ◽

Sandro Cecili

Keyword(s):

Municipal Wastewater ◽

Treatment Plant ◽

Oxygen Demand ◽

Granular Sludge ◽

Batch Process ◽

Innovative Technology ◽

Municipal Wastewater Treatment ◽

The City ◽

Aerobic Sludge ◽

New System

The present paper shows the results obtained through an experimental activity carried out on a pilot-scale plant using an innovative technology which couples the granular aerobic sludge with the sequencing batch process. Treatment efficiency and operation costs were evaluated in order to assess feasibility of this new technology for the upgrading of the existing continuous flow activated sludge treatment plant located in Casal Monastero, a decentralized area of the City of Rome. During start-up (about 3 months), the granular aerobic sludge was developed by controlling the dissolved oxygen concentration, the value of pH and the up-flow velocity. Besides, the influent organic loading was progressively increased starting from 0.1 kg/m3 d up to 0.9 kg/m3 d. In order to improve nitrogen removal, an anoxic phase was temporary added to the operative cycle. Complete development of the granular sludge determined an appreciable improvement of the denitrification process which allowed to eliminate the anoxic phase. At regime conditions, the plant was operated with 3 daily cycles, each one of 8 h. The new system showed a reduced sludge production (of about 20–35%) as compared to the existing plant, along with high removal efficiency of both Chemical Oxygen Demand (COD) and nitrogen. However, the operation was discontinuous and strictly related to the strength of the granular sludge. Therefore, a careful monitoring is recommended in order to control operation and performance of this new system.

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The Mechanism of Nitrogen Removal in Domestic Sewage of High Ammonia Nitrogen by Three-Step Series Constructed Rapid Infiltration System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.356-360.1248 ◽

2011 ◽

Vol 356-360 ◽

pp. 1248-1252

Author(s):

Ai Bin Kang ◽

Ying Qiang Yao ◽

Yu Long Dong

Keyword(s):

Wastewater Treatment ◽

Total Nitrogen ◽

Municipal Wastewater ◽

Removal Rate ◽

Treatment Plant ◽

Ammonia Nitrogen ◽

Domestic Sewage ◽

Municipal Wastewater Treatment ◽

High Ammonia ◽

Nitrite Oxidizing Bacteria

The removal and mechanism of ammonia nitrogen and total nitrogen were studie through three-step series of constructed rapid infiltration system by using high ammonia nitrogen domestic sewage of students' living area in a university. The result shows that the removal rate of ammonia nitrogen is 94.47% by using this system, which is 3% higher than conventional rapid infiltration system.The effluent can meet the standard Ⅰ—A of “Discharge standard of pollutants for municipal wastewater treatment plant(GB 18918-2002)”. The amount of ammonium oxidizing bacteria, nitrate oxidizing bacteria, nitrite oxidizing bacteria in this system is higher than that in conventional rapid infiltration system. The correlation between the removal of ammonia nitrogen and ammonium oxidizing bacteria, nitrate oxidizing bacteria, nitrite oxidizing bacteria is significant. The removal rate of total nitrogen is 47.38% by using this system, which is 20.72% higher than that in conventional rapid infiltration system. However, the effluent still can not meet the standard Ⅰ—A of “Discharge standard of pollutants for municipal wastewater treatment plant (GB 18918-2002)”. The amount of denitrifying bacteria in the three-step subsystem increased significantly, which improves the removal of total nitrogen. The correlation between the removal of TN and denitrification bacteria is significant.

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Effectiveness of septage pre-treatment in vertical flow constructed wetlands

Water Science & Technology ◽

10.2166/wst.2017.398 ◽

2017 ◽

Vol 76 (9) ◽

pp. 2544-2553 ◽

Cited By ~ 5

Author(s):

Beata Karolinczak ◽

Wojciech Dąbrowski

Keyword(s):

Constructed Wetlands ◽

Municipal Wastewater ◽

Oxygen Demand ◽

Vegetation Period ◽

Ammonia Nitrogen ◽

Vertical Flow ◽

Municipal Wastewater Treatment ◽

Vertical Flow Constructed Wetlands ◽

Hydraulic Load ◽

Pre Treatment

Abstract Septage is wastewater stored temporarily in cesspools. A periodic supply of its significant quantities to small municipal wastewater treatment plants (WWTPs) may cause many operational problems. In the frame of the research, it has been proposed to utilize vertical flow constructed wetlands for pre-treatment of septage prior to its input to the biological stage of a WWTP. The aim of the work was to assess the effectiveness of pre-treatment in relation to factors such as: seasonality, hydraulic load, pollutants load of the VF bed and interactions between these factors. The results proved that application of a VF bed to septage pre-treatment can significantly reduce the concentration of pollutants (biochemical oxygen demand (BOD5): 82%, chemical oxygen demand (COD): 82%, total suspended solids (TSS): 91%, total nitrogen (TN): 47%, ammonia nitrogen (NH4-N): 70%), and thus decrease the loading of the biological stage of a WWTP. The mathematical models of mass removal process were created. They indicate that in case of all analysed parameters, removed load goes up with the increase of load in the influent. However, with the increase of hydraulic load, a decrease of the removed BOD5, COD, TSS and total phosphorus, and in vegetation period an increase of TN, can be observed in terms of load. There are no statistically significant effects of seasonality.

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