Nitrogen and Phosphorus Removal from Wastewater by Useful Plants and the Effect of Shading on the Removal Efficiency.

Abstract The environmental problems related to rural domestic sewage treatment are becoming increasingly serious, and society is also concerned about them. A baffled vertical flow constructed wetland (BVFCW) is a good choice for cleaning wastewater. Herein, a drinking-water treatment sludge-BVFCW (D-BVFCW) parallel with ceramsite-BVFCW (C-BVFCW) planted with Oenanthe javanica (O. javanica) to treat rural domestic sewage was investigated, aiming to compare nitrogen and phosphorus removal efficiency in different BVFCWs. A removal of 23.9% NH4+-N, 24.6% total nitrogen (TN) and 76.7% total phosphorus (TP) occurred simultaneously in the D-BVFCW; 56.4% NH4+-N, 60.8% TN and 55.2% TP respectively in the C-BVFCW. The root and plant height increased by an average of 7.9 cm and 8.3 cm, respectively, in the D-BVFCW, and by 0.7 cm and 1.1 cm, respectively, in the C-BVFCW. These results demonstrate that the D-BVFCW and C-BVFCW have different effects on the removal of N and P. The D-BVFCW mainly removed P, while C-BVFCW mainly removed N.

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Enhancing nitrogen and phosphorus removal in the BUCT–IFAS process by bypass flow strategy

Water Science & Technology ◽

10.2166/wst.2015.242 ◽

2015 ◽

Vol 72 (4) ◽

pp. 528-534 ◽

Cited By ~ 5

Author(s):

Yang Bai ◽

Xie Quan ◽

Yaobin Zhang ◽

Shuo Chen

Keyword(s):

Carbon Source ◽

Removal Efficiency ◽

Phosphorus Removal ◽

P Uptake ◽

Flow Mode ◽

Bypass Flow ◽

Nitrogen And Phosphorus ◽

Nitrogen And Phosphorus Removal ◽

University Of Cape Town ◽

P Removal

A University of Cape Town process coupled with integrated fixed biofilm and activated sludge system was modified by bypass flow strategy (BUCT–IFAS) to enhance nitrogen and phosphorus removal from the wastewater containing insufficient carbon source. This process was operated under different bypass flow ratios (λ were 0, 0.4, 0.5, 0.6 and 0.7, respectively) to investigate the effect of different operational modes on the nitrogen (N) and phosphorus (P) removal efficiency (λ = 0 was noted as common mode, other λ were noted as bypass flow mode), and optimizing the N and P removal efficiency by altering the λ. Results showed that the best total nitrogen (TN) and total phosphorus (TP) removal performances were achieved at λ of 0.6, the effluent TN and TP averaged 14.0 and 0.4 mg/L meeting discharge standard (TN < 15 mg/L, TP < 0.5 mg/L). Correspondingly, the TN and TP removal efficiencies were 70% and 94%, respectively, which were 24 and 41% higher than those at λ of 0. In addition, the denitrification and anoxic P-uptake rates were increased by 23% and 23%, respectively, compared with those at λ of 0. These results demonstrated that the BUCT–IFAS process was an attractive method for enhancing nitrogen and phosphorus removal from wastewater containing insufficient carbon source.

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Use of zeolites for macronutrients removal from wastewater

Acta Chimica Slovaca ◽

10.2478/acs-2019-0021 ◽

2019 ◽

Vol 12 (1) ◽

pp. 150-161

Author(s):

Barbora Urminská ◽

Ján Derco ◽

Ronald Zakhar ◽

Adriana Korpicsová

Keyword(s):

Removal Efficiency ◽

Phosphorus Removal ◽

Natural Zeolite ◽

Ammonium Nitrogen ◽

Nitrogen And Phosphorus ◽

Nitrogen And Phosphorus Removal ◽

Physical Chemical ◽

Synthetic Zeolites ◽

Modified Zeolites ◽

Preliminary Research

Abstract Natural or synthetic zeolites have unique physical, chemical and structural properties that predetermine their use in many processes, including wastewater treatment. This study presents the results of our preliminary research in the field of nitrogen and phosphorus removal using adsorption and adsorptive ozonation with natural and modified zeolites. Iron-modified zeolite was the most efficient for the removal of ammonium nitrogen by adsorption. Phosphorus removal efficiency using adsorption was relatively low and natural zeolite was not suitable for the phosphorus removal at all. Ozone had no significant impact on the removal efficiency. Regeneration of loaded zeolites with ozone has also been studied. This method was partly efficient but it needs be further examined.

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Enhanced Nitrogen and Phosphorus Removal by Natural Pyrite based Constructed Wetland with Intermittent Aeration

10.21203/rs.3.rs-389894/v1 ◽

2021 ◽

Author(s):

Liya Li ◽

Jingwei Feng ◽

Liu Zhang ◽

Hao Yin ◽

Chunli Fan ◽

...

Keyword(s):

Removal Efficiency ◽

Phosphorus Removal ◽

Nitrification Rate ◽

Intermittent Aeration ◽

Nitrogen And Phosphorus ◽

Nitrogen And Phosphorus Removal ◽

Monooxygenase Activity ◽

Ferrous Sulfide ◽

Natural Pyrite ◽

Front Section

Abstract Four subsurface flow constructed wetlands (SFCWs) filled with different substrates including ceramsite, ceramsite + pyrite, ceramsite + ferrous sulfide, and ceramsite + pyrite + ferrous sulfide (labeled as SFCW-S1, SFCW-S2, SFCW-S3, and SFCW-S4) were constructed, and the removal of nitrogen and phosphorus by these SFCWs coupled with intermittent aeration in the front section was discussed. The key findings from different substrate analyses, including nitrification and denitrification rate, enzyme activity, microbial community structure, and the X-ray diffraction, revealed the nitrogen and phosphorus removal mechanism. The results showed that the nitrogen and phosphorus removal efficiency for SFCW-S1 always remains the lowest, and the phosphorus removal efficiency for SFCW-S4 is recorded as the highest one. However, after controlling the dissolved oxygen by intermittent aeration in the front section of SFCWs, the nitrogen and phosphorus removal efficiencies of SFCWs-S2 and S4 becomes higher than those of SFCW-S1, and SFCW-S3. It was noticed that the pollutants were removed mainly in the front section of the SFCWs. Both precipitation and adsorption on the substrate were the main mechanisms for phosphorus removal. A minute difference of nitrification rate and ammonia monooxygenase activity was observed in the SFCWs aeration zone. The denitrification rates, nitrate reductase, nitrite reductase, and electron transport system activity for SFCW-S2 and SFCW-S4 were higher than those detected for SFCW-S1 and SFCW-S3 in the non-aerated zone. Proteobacteria was the largest phyla found in the SFCWs. Moreover, Thiobacillus occupied a large proportion found in SFCW-S2, and SFCW-S4, and it played a crucial role in pyrite-driven autotrophic denitrification.

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Effect of SRT on Nitrogen and Phosphorus Removal in Modified Carrousel Oxidation Ditch Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.396-398.1995 ◽

2011 ◽

Vol 396-398 ◽

pp. 1995-2001

Author(s):

Lian Yu

Keyword(s):

Water Temperature ◽

Removal Efficiency ◽

Phosphorus Removal ◽

Synthetic Wastewater ◽

Oxidation Ditch ◽

Nitrogen And Phosphorus ◽

Nitrogen And Phosphorus Removal ◽

Operation Conditions ◽

Carrousel Oxidation Ditch

Based on a modified Carrousel oxidation ditch process acclimated with synthetic wastewater，effect of SRT on nitrogen and phosphorus removal occurred in the system was investigated. The results indicated that SRT was prominent to nitrogen and phosphorus removal. The removal efficiency of nitrogen was better with SRT extension and that the removal efficiency of phosphorus was better with SRT shortness. With the operation conditions of water temperature 30°C, SRT 11days, the removal efficiency of TN and TP reached 85.4% and 74.9%, which indicated that nitrogen and phosphorus removals were best.

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Impacts of variable pH on stability and nutrient removal efficiency of aerobic granular sludge

Water Science & Technology ◽

10.2166/wst.2015.460 ◽

2015 ◽

Vol 73 (1) ◽

pp. 60-68 ◽

Cited By ~ 4

Author(s):

Monireh Lashkarizadeh ◽

Giulio Munz ◽

Jan A. Oleszkiewicz

Keyword(s):

Removal Efficiency ◽

Nutrient Removal ◽

Phosphorus Removal ◽

Granular Sludge ◽

Aerobic Granular Sludge ◽

Acidic Ph ◽

Alkaline Ph ◽

Nitrogen And Phosphorus ◽

Nitrogen And Phosphorus Removal ◽

Ph Shock

The impact of pH variation on aerobic granular sludge stability and performance was investigated. A 9-day alkaline (pH = 9) and acidic (pH = 6) pH shocks were imposed on mature granules with simultaneous chemical oxygen demand (COD), nitrogen and phosphorus removal. The imposed alkaline pH shock (pH 9) reduced nitrogen and phosphorus removal efficiency from 88% and 98% to 66% and 50%, respectively, with no further recovery. However, acidic pH shock (pH 6) did not have a major impact on nutrient removal and the removal efficiencies recovered to their initial values after 3 days of operation under the new pH condition. Operating the reactors under alkaline pH induced granules breakage and resulted in an increased solids concentration in the effluent and a significant decrease in the size of the bio-particles, while acidic pH did not have significant impacts on granules stability. Changes in chemical structure and composition of extracellular polymeric substances (EPS) matrix were suggested as the main factors inducing granules instability under high pH.

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Cultivation in SBR System and Screening of Simultaneous Nitrogen and Phosphorus Removal Strain with Identification

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.5347 ◽

2012 ◽

Vol 518-523 ◽

pp. 5347-5350

Author(s):

Jia Xie ◽

Xiao Xiang Zhao ◽

Xin Shan Song ◽

Jun Hu Wei

Keyword(s):

Removal Efficiency ◽

Phosphorus Removal ◽

Batch Reactor ◽

Oxygen Demand ◽

Ammonia Nitrogen ◽

Phosphate Removal ◽

Aerobic Granular Sludge ◽

Nitrogen And Phosphorus ◽

Nitrogen And Phosphorus Removal ◽

High Efficient

The successful cultivation of aerobic granular sludge used for simultaneous nitrogen and phosphorus removal in sequencing batch reactor (SBR) was performed using a synthetic domestic wastewater and conventional flocculent activated sludge as seeding sludge. The removal efficiency of sludge for chemical oxygen demand (COD),ammonia nitrogen and phosphate was 92.4%,88.1% and 95.9%, respectively. After screening, a strain was obtained with high efficient in nitrogen and phosphorus removal. By analyzing, the strain was identified as Raoultella ornithinolytica. After strain accumulation, the strain cultured at 30°C for 24h. The ammonia nitrogen and phosphate removal efficiency were 78.3% and 92%, respectively.

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An evaluation of duckweed-based pond systems as an alternative option for decentralised treatment and reuse of wastewater in Zimbabwe

Water Science & Technology ◽

10.2166/wst.2003.0137 ◽

2003 ◽

Vol 48 (2) ◽

pp. 323-330 ◽

Cited By ~ 6

Author(s):

I. Nhapi ◽

J. Dalu ◽

J. Ndamba ◽

M.A. Siebel ◽

H.J. Gijzen

Keyword(s):

Removal Efficiency ◽

Phosphorus Removal ◽

Field Measurements ◽

Good Alternative ◽

Full Scale ◽

Design Criteria ◽

Nitrogen And Phosphorus ◽

Nitrogen And Phosphorus Removal ◽

High Nutrient ◽

Duckweed Pond

A study was carried out in Zimbabwe to evaluate the performance of duckweed ponds as an option for treating and reusing wastewater in small, decentralised communities. The study focused on nitrogen and phosphorus removal, operational problems, and duckweed application. Two full-scale trial plants at Nemanwa and Gutu-Mupandawana growth points were used. Sewage samples were collected and analysed monthly from September 2000 to August 2001 for NO3, NH4-, TKN, TP, COD, and other field measurements. The duckweed was harvested daily and fed to chickens. The Nemanwa plant had high nutrient levels due to nil outflows caused by water rationing in the area. The Gutu effluent had averages of 38.7 ± 23.1 mg/l TN and 7.5 ± 2.4 mg/l TP which are above the respective Zimbabwean standards of 10 mg/l TN and 1 mg/l TP. COD removal efficiency at Gutu was poor at 45%. The performance of Gutu and Nemanwa plants suffered from inappropriate design especially pond depth and short-circuiting. The duckweed died off in the November-January period, this being attributed to excessive levels of ammonia. It was concluded that the duckweed pond systems would offer a good alternative for managing and reusing wastewater at community level provided due regard is paid to appropriate design criteria.

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