A four-year mass balance for a natural wetland system receiving domestic wastewater

In order to clarify the natural purification potential of a natural wetland having free-flowing water, we performed a four-year study on such a wetland system which had been receiving for 12 years the domestic wastewater discharged from a residential area comprised of 45 households. The wetland's removal rate of organic matter throughout the four years ranged from 80% for COD to 95% for BOD, whereas the corresponding nitrogen removal rate was comparatively lower. Results indicate that NH4-N release from the bottom sediment and repression of nitrification are the main factors responsible for the wetland's low removal rate of nitrogen during winter. The wetland purification performance even in winter was determined as follows (g m−2 d−1): 2.2 BOD, 0.81 COD, 1.1 TOC, 0.10 T-N, and 0.023 T-P.

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Effect of earthworm loads on organic matter and nutrient removal efficiencies in synthetic domestic wastewater, and on bacterial community structure and diversity in vermifiltration

Water Science & Technology ◽

10.2166/wst.2013.178 ◽

2013 ◽

Vol 68 (1) ◽

pp. 43-49 ◽

Cited By ~ 17

Author(s):

L. M. Wang ◽

X. Z. Luo ◽

Y. M. Zhang ◽

J. J. Lian ◽

Y. X. Gao ◽

...

Keyword(s):

Organic Matter ◽

Community Structure ◽

Bacterial Community ◽

Bacterial Community Structure ◽

Removal Rate ◽

Oxygen Demand ◽

Domestic Wastewater ◽

Ammonia Nitrogen ◽

Domestic Sewage ◽

Shannon Index

In this paper, we studied the effect of earthworm loads on the removal rates of chemical oxygen demand (COD), ammonia nitrogen (NH3-N), total nitrogen, and total phosphorus from synthetic domestic sewage and on the bacterial community structure and diversity of substrates in earthworm packing beds. The different vermifiltrations (VFs), including the control, are successful in removing both organic matter (OM) and nutrients. The removal rate of NH3-N at 12.5 g of earthworm/L of soil VF is higher compared with that at 0 and 4.5 earthworm load VFs. The highest Shannon index, in the earthworm packing bed, occurred at 16.5 earthworm load VF. Furthermore, the COD removal rate is significantly correlated with the Shannon index, which reveals that OM removal for synthetic domestic sewage treatment at VF might be more dependent on bacterial diversity at the earthworm packing bed. The band distributions and diversities of the bacterial community for samples from different earthworm loads in VFs suggest that the bacterial community structure was only affected within the earthworm packing bed when the earthworm load reached a certain level. The present study adds to the current understanding of OM and nutrient degradation processes in VF domestic wastewater treatment.

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Enhanced P, N and C removal from domestic wastewater using constructed wetland employing construction solid waste (CSW) as main substrate

Water Science & Technology ◽

10.2166/wst.2012.277 ◽

2012 ◽

Vol 66 (5) ◽

pp. 1022-1028 ◽

Cited By ~ 14

Author(s):

Y. Yang ◽

Z. M. Wang ◽

C. Liu ◽

X. C. Guo

Keyword(s):

Organic Matter ◽

Solid Waste ◽

Constructed Wetland ◽

Tidal Flow ◽

Domestic Wastewater ◽

Treatment System ◽

Ammoniacal Nitrogen ◽

Wetland System ◽

Main Substrate ◽

P Removal

Construction solid waste (CSW), an inescapable by-product of the construction and demolition process, was used as main substrate in a four-stage vertical subsurface flow constructed wetland system to improve phosphorus P removal from domestic wastewater. A ‘tidal flow’ operation was also employed in the treatment system. Under a hydraulic loading rate (HLR) of 0.76 m3/m2 d for 1st and 3rd stage and HLR of 0.04 m3/m2 d for 2nd and 4th stage of the constructed wetland system respectively and tidal flow operation strategy, average removal efficiencies of 99.4% for P, 95.4% for ammoniacal-nitrogen, 56.5% for total nitrogen and 84.5% for total chemical oxygen demand were achieved during the operation period. The CSW-based constructed wetland system presents excellent P removal performance. The adoption of tidal flow strategy creates the aerobic/anoxic condition intermittently in the treatment system. This can achieve better oxygen transfer and hence lead to more complete nitrification and organic matter removal and enhanced denitrification. Overall, the CSW-based tidal flow constructed wetland system holds great promise for enabling high rate removal of P, ammoniacal-nitrogen and organic matter from domestic wastewater, and transforms CSW from a waste into a useful material.

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CHARACTERIZATION OF SEDIMENT AND ORGANIC MATTER IN A UNIQUE NATURAL WETLAND SYSTEM IN SOUTHWEST MICHIGAN

10.1130/abs/2019am-339670 ◽

2019 ◽

Author(s):

Jillian Marie Ashton ◽

◽

Jessalyn Mari Gonzalez ◽

Tara Kneeshaw ◽

Jennifer Metz Brenneman

Keyword(s):

Organic Matter ◽

Natural Wetland ◽

Wetland System ◽

Southwest Michigan

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

Water Science & Technology ◽

10.2166/wst.1998.0809 ◽

1998 ◽

Vol 38 (8-9) ◽

pp. 213-221 ◽

Cited By ~ 3

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 (> 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.

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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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Study on De-Nitrification of Improved Step-Feed Progress

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.703.171 ◽

2014 ◽

Vol 703 ◽

pp. 171-174

Author(s):

Bing Wang ◽

Yi Xiao ◽

Shou Hui Tong ◽

Lan Fang ◽

Da Hai You ◽

...

Keyword(s):

Water Quality ◽

Organic Matter ◽

Fluidized Bed ◽

Removal Efficiency ◽

Nitrogen Removal ◽

Removal Rate ◽

Operating Conditions ◽

Removal Mechanism ◽

Aerobic Zone

Improved step-feed de-nitrification progress combined with biological fluidized bed was introduced in this study. The progress had good performance and capacity of de-nitrification and organic matter. The experiment result showed that the de-nitrification efficiency of the improved biological fluidized bed with step-feed process was higher than the fluidized bed A/O process under the same water quality and the operating conditions. When the influent proportion of each segment was equal, the system showed good nitrogen removal efficiency with the change of influent C/N ratio, HRT and sludge return ratio. The removal rate of TN reached up to 88.2%. It showed that the simultaneous nitrification and de-nitrification phenomenon happened in the aerobic zone. The nitrogen removal mechanism was also studied.

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Isolation and characterization of organic matter-degrading bacteria from coking wastewater treatment plant

Water Science & Technology ◽

10.2166/wst.2018.427 ◽

2018 ◽

Vol 78 (7) ◽

pp. 1517-1524 ◽

Cited By ~ 2

Author(s):

Riqiang Li ◽

Jianxing Wang ◽

Hongjiao Li

Keyword(s):

Organic Matter ◽

Wastewater Treatment ◽

Wastewater Treatment Plant ◽

Removal Rate ◽

Treatment Plant ◽

Coking Wastewater ◽

Naphthalene Degradation ◽

Isolation And Characterization ◽

Degrading Bacteria

Abstract As a step toward bioaugmentation of coking wastewater treatment 45 bacteria strains were isolated from the activated sludge of a coking wastewater treatment plant (WWTP). Three strains identified as Bacillus cereus, Pseudomonas synxantha, and Pseudomonas pseudoaligenes exhibited high dehydrogenase activity which indicates a strong ability to degrade organic matter. Subsequently all three strains showed high naphthalene degradation abilities. Naphthalene is a refractory compound often found in coking wastewater. For B. cereus and P. synxantha the maximum naphthalene removal rates were 60.4% and 79.8%, respectively, at an initial naphthalene concentration of 80 mg/L, temperature of 30 °C, pH of 7, a bacteria concentration of 15% (V/V), and shaking speed of 160 r/min. For P. pseudoaligenes, the maximum naphthalene removal rate was 77.4% under similar conditions but at 35 °C.

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Removal Efficiency of Three Cold-Climate Constructed Wetlands Treating Domestic Wastewater: Effects of Temperature, Seasons, Loading Rates and Input Concentrations

Water Science & Technology ◽

10.2166/wst.1999.0172 ◽

1999 ◽

Vol 40 (3) ◽

pp. 273-281 ◽

Cited By ~ 23

Author(s):

Trond Mæhlum ◽

Per Stålnacke

Keyword(s):

Organic Matter ◽

Constructed Wetlands ◽

Domestic Wastewater ◽

Cold Climate ◽

Treatment Efficiency ◽

Loading Rates ◽

P Sorption ◽

Percentage Points ◽

Effects Of Temperature ◽

Pre Treatment

This paper outlines the influence of temperature, flow rate and input concentrations on the treatment efficiency of organic matter and nutrients in constructed wetlands (CWs). Three integrated 10 PE systems with horizontal subsurface flow (HSF) treating domestic wastewater are described. Particular attention is devoted to: (1) aerobic pre-treatment in vertical-flow filters, (2) filter media with high phosphorus (P) sorption capacity, and (3) the treatment efficiency during winters. Aerobic pre-treatment followed by CW units including P sorption media removed most organic matter (BOD> 75%), P (> 90%) and total and ammonia N (40-80%). P retention was relatively stable in wetland filters, both with lightweight aggregates and ferruginous sand during 3-6 years of monitoring. Iron-rich sand from Bsh and Bs horizons of ferro-humic podzols was efficient for P sorption, but removal efficiencies of COD, TOC and SS were negative. The differences in efficiency between cold and warm periods were less than 10 percentage points for all parameters. It is anticipated that temperature effects are partially compensated by the large hydraulic retention time. The findings suggest that HSF systems do not require vegetation.

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