Treatment of high-salt oil produced water based on constructed wetland technology—A case study of a costal oilfield

Aiming at the treatment of large volume of oil produced wastewater, the combined technology based on constructed wetland was applied for produced water treatment in a costal oil field. During the stable operation period, the treatment system maintained removal efficiency of 50.2% for chemical oxygen demand (COD), 100% for oil and 85.1% for ammonium nitrogen (NH3-N) under the gradient increase of salinity along the process. Meanwhile, this system has a good ability to adapt the influent fluctuation. When the oil in the influent fluctuated greatly between 11 mg/L to 147 mg/L, the effluent water quality remained stable. The treated water met the national discharge standard for water pollutants from the oilfield industry and can be used for the saline alkali beach wetland as supplement water.

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Performance and microbial community in a combined VF-HF system for the advanced treatment of secondary effluent

Water Science & Technology ◽

10.2166/wst.2018.243 ◽

2018 ◽

Vol 2017 (3) ◽

pp. 695-706 ◽

Cited By ~ 2

Author(s):

Zhichao Zhu ◽

Hengfeng Miao ◽

Yajing Zhang ◽

Jian Cui ◽

Zhenxing Huang ◽

...

Keyword(s):

Nitrogen Removal ◽

Constructed Wetland ◽

Treatment Plant ◽

Oxygen Demand ◽

Community Analysis ◽

Denitrifying Bacteria ◽

Ammonium Nitrogen ◽

Pollutant Removal ◽

Stable Operation ◽

Secondary Effluent

Abstract In this study, a laboratory-scale system combined a vertical flow constructed wetland (VF) with a horizontal flow constructed wetland (HF), which was used to treat the secondary effluent of a wastewater treatment plant. Removal efficiencies of 67.02%, 89.80%, 90.31% and 75.38% were achieved by the system for chemical oxygen demand (COD), ammonium nitrogen (NH4+-N), total nitrogen (TN) and total phosphorus (TP), respectively. The VF showed much higher average loading rates of COD, TP, NH4+-N and TN (7.96 g/m2/d, 0.076 g/m2/d, 0.31 g/m2/d and 0.99 g/m2/d) than in HF (0.65 g/m2/d, 0.016 g/m2/d, 0.25 g/m2/d and 0.50 g/m2/d), during the stable operation period. Biodegradation played a major role in pollutant removal, especially for COD and TN. The results of bacterial community analysis indicated that heterotrophic denitrifying bacteria (Hydrogenophaga and Flavobacterium) were the dominant contributors for nitrogen removal in the VF, while heterotrophic denitrifying bacteria (Rhodobacter, Flavobacterium and Dechloromonas) and the autotrophic denitrifying bacteria Sulfurimonas played the principal roles for nitrogen removal in the HF. Redundancy analyses showed that COD and NH4+-N were the important factors affecting the distribution of nitrogen removal bacteria in the VF, while pH, dissolved oxygen and oxidation-reduction potential were the key factors influencing the distribution of nitrogen removal bacteria in the HF.

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In Situ Nutrient Removal from Rural Runoff by A New Type Aerobic/Anaerobic/Aerobic Water Spinach Wetlands

Water ◽

10.3390/w11051100 ◽

2019 ◽

Vol 11 (5) ◽

pp. 1100 ◽

Cited By ~ 1

Author(s):

Ya-Wen Wang ◽

Hua Li ◽

You Wu ◽

Yun Cai ◽

Hai-Liang Song ◽

...

Keyword(s):

Nitrogen Removal ◽

Constructed Wetland ◽

Removal Rate ◽

Oxygen Demand ◽

Ammonium Nitrogen ◽

Water Spinach ◽

Nitrogen And Phosphorus ◽

The Matrix ◽

New Type ◽

Nitrification And Denitrification

Rural runoff with abundant nutrients has become a great threat to aquatic environment. Hence, more and more attention has been focused on nutrients removal. In this study, an improved aerobic/anaerobic/aerobic three-stage water spinach constructed wetland (O-A-O-CW) was used to improve the removal of nitrogen and phosphorus of rural runoff. The removal rate of the target pollutants in O-A-O-CW was compared with the common matrix flow wetland as well as the no-plant wetland. The results showed that the O-A-O-CW significantly increased the chemical oxygen demand, total phosphorus, ammonium-nitrogen, nitrate, and total nitrogen removal rate, and the corresponding removal rate was 55.85%, 81.70%, 76.64%, 89.78%, and 67.68%, respectively. Moreover, the best hydraulic condition of the wetland, including hydraulic retention time and hydraulic loading, was determined, which were 2 days and 0.45 m3·m−2·day−1, respectively. Furthermore, the removal mechanism of the constructed wetland was thoroughly studied, which included the adsorption of nitrogen and phosphorus by the matrix and water spinach, and the nitrification and denitrification by the bacteria. The results demonstrated that the mechanisms of nitrogen removal in the new type wetland were principally by the nitrification and denitrification process. Additionally, adsorption and precipitation by the matrix are mainly responsible for phosphorus removal. These results suggested that the new O-A-O-CW can efficiently removal nutrients and enhance the water quality of the rural runoff.

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Performance of Earthworm-Enhanced Horizontal Sub-Surface Flow Filter and Constructed Wetland

Water ◽

10.3390/w10101309 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1309 ◽

Cited By ~ 5

Author(s):

Rajendra Singh ◽

Dafang Fu ◽

Jing Jia ◽

Jiaguo Wu

Keyword(s):

Constructed Wetland ◽

Low Impact Development ◽

Oxygen Demand ◽

Ammonium Nitrogen ◽

Surface Flow ◽

Water Levels ◽

Operating Conditions ◽

Experimental Conditions ◽

Hydraulic Load ◽

Removal Efficiencies

In this study, the performance of the horizontal sub-surface flow filter (HSSFF) and constructed wetland (HSSFCW) experimental units enhanced with earthworms was investigated for the treatment of construction camp sewage wastewater. All the experimental units (filter and constructed wetland) were filled with the same filler except Eisenia foetida earthworms and Lolium perenne Linn plants. The performance of the earthworm-enhanced filter (EEF) and the earthworm-enhanced constructed wetland (EECW) was compared to that of the blank filter (BF) units. The results revealed that the removal efficiencies for chemical oxygen demand (COD), ammonium-nitrogen (NH4+-N), total nitrogen (TN) and total phosphorus (TP) in EEF were higher than the BF unit. In order to optimize the operating conditions, the experiments were conducted in three different water levels. The results revealed that the removal efficiencies of EEF for these pollutants are the highest in experimental conditions no. 2 (water level ~30 cm; HRT ~3 days; hydraulic load ~4.05 cm/day; and Inflow discharge ~0.27 L/h). Compared to the EEF and BF units, the EECW has higher removal efficiency for COD and TN and has more stable performance than the filters. This work will aid the design and improvement of filters and CWs for treatment of effluent wastewater from construction camps. The selection of appropriate hydraulic parameters and experimental conditions could be very beneficial in achieving the goal of implantation of low impact development (LID).

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Distillation of oil field produced water for reuse on irrigation water: evaluation of pollutants removal and ecotoxicity

Journal of Water Reuse and Desalination ◽

10.2166/wrd.2011.044 ◽

2011 ◽

Vol 1 (4) ◽

pp. 224-236 ◽

Cited By ~ 5

Author(s):

Barbara G. Andrade ◽

Vívian T. Andrade ◽

Byron R. S. Costa ◽

Juacyara C. Campos ◽

Márcia Dezotti

Keyword(s):

Produced Water ◽

Saline Water ◽

Ammonium Nitrogen ◽

Ammonia Removal ◽

Oil Field ◽

Pseudokirchneriella Subcapitata ◽

Produce Water ◽

Water Distillation ◽

Pollutants Removal ◽

Ecotoxicological Assays

Desalination is one of the earliest forms of saline water treatment and it is still used throughout the world. In this work, a single-effect mechanical vapor compression (MVC) process was investigated to produce water for irrigation of non-edible cultures from oil-field produced water. Distillation was able to produce a condensate presenting very low amounts of 84 analyzed pollutants. Ecotoxicological assays with Pseudokirchneriella subcapitata algae, Danio rerio fish, lettuce (Lactuca sativa) and earthworm (Eisenia fetida) were performed in condensate. The condensate was non-toxic for all tested organisms, except for P. subcapitata algae that showed some level of chronic toxicity caused by ammonium nitrogen. This toxic effect was confirmed by conducting a series of ecotoxicological assays with condensate samples after ammonia removal (stripping). The condensate presented quality acceptable for irrigation of non-edible crops.

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A Case Study on Treating Oil Contaminants and Heavy Metal of Produced Water Through Phytoremediation Using Reed Bed Technology: A Success Story of 15 Years Operation of Heglig Oil Field of Sudan

10.2118/194575-ms ◽

2019 ◽

Author(s):

Ajay Kumar ◽

Yasir Ibrahim ◽

Badrelddin Atta ◽

Vijendra Singh ◽

Omer Musa Elmubarak ◽

...

Keyword(s):

Heavy Metal ◽

Produced Water ◽

Oil Field ◽

Success Story ◽

Reed Bed

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Experiences from the full-scale implementation of a new two-stage vertical flow constructed wetland design

Water Science & Technology ◽

10.2166/wst.2013.708 ◽

2013 ◽

Vol 69 (2) ◽

pp. 335-342 ◽

Cited By ~ 2

Author(s):

Guenter Langergraber ◽

Alexander Pressl ◽

Raimund Haberl

Keyword(s):

Constructed Wetland ◽

Oxygen Demand ◽

Ammonia Nitrogen ◽

Full Scale ◽

Vertical Flow ◽

Effluent Water ◽

Two Stage ◽

Vertical Flow Constructed Wetland ◽

Hydraulic Load ◽

Public Holidays

This paper describes the results of the first full-scale implementation of a two-stage vertical flow constructed wetland (CW) system developed to increase nitrogen removal. The full-scale system was constructed for the Bärenkogelhaus, which is located in Styria at the top of a mountain, 1,168 m above sea level. The Bärenkogelhaus has a restaurant with 70 seats, 16 rooms for overnight guests and is a popular site for day visits, especially during weekends and public holidays. The CW treatment system was designed for a hydraulic load of 2,500 L.d−1 with a specific surface area requirement of 2.7 m2 per person equivalent (PE). It was built in fall 2009 and started operation in April 2010 when the restaurant was re-opened. Samples were taken between July 2010 and June 2013 and were analysed in the laboratory of the Institute of Sanitary Engineering at BOKU University using standard methods. During 2010 the restaurant at Bärenkogelhaus was open 5 days a week whereas from 2011 the Bärenkogelhaus was open only on demand for events. This resulted in decreased organic loads of the system in the later period. In general, the measured effluent concentrations were low and the removal efficiencies high. During the whole period the ammonia nitrogen effluent concentration was below 1 mg/L even at effluent water temperatures below 3 °C. Investigations during high-load periods, i.e. events like weddings and festivals at weekends, with more than 100 visitors, showed a very robust treatment performance of the two-stage CW system. Effluent concentrations of chemical oxygen demand and NH4-N were not affected by these events with high hydraulic loads.

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