Efficiency of Nannochloropsis oculata and Bacillus polymyxa symbiotic composite at ammonium and phosphate removal from synthetic wastewater

Abstract The effects of autotrophic and mixotrophic conditions on microalgae growth and nutrient removal efficiency from synthetic wastewater by different microalgae were investigated. Although several studies have demonstrated the suitability of microalgae technologies for ammonia-rich wastewater treatment, only a few have been used for treatment of phosphate-rich industrial wastewaters. In this work, six microalgae were cultivated in batch mode in a growth medium with a high phosphate concentration (0.74 Mm PO43−-P) and different carbon sources (ammonium acetate and sodium bicarbonate) without CO2 supplementation or pH adjustment. Their potential for nutrient removal and biomass generation was estimated. The biomass growth in the reactors was modeled and the data aligned to the Verhulst model with R2 > 0.93 in all cases. Chlorella pyrenoidosa ACUF_808 showed the highest final biomass productivity of 106.21 and 75.71 mg·L−1·d−1 in media with inorganic and organic carbon sources, respectively. The highest phosphorus removal efficiency was 32% with Chlorella vulgaris ACUF_809, while the nitrate removal efficiency in all reactors exceeded 93%. The coupled cultivation of the novel isolated strains of C. pyrenoidosa and C. vulgaris under mixotrophic conditions supplemented with ammonium acetate might be a promising solution for simultaneous nitrate and phosphate removal from phosphorus-rich wastewaters.

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Ureolytic phosphate precipitation from anaerobic effluents

Water Science & Technology ◽

10.2166/wst.2009.193 ◽

2009 ◽

Vol 59 (10) ◽

pp. 1983-1988 ◽

Cited By ~ 7

Author(s):

E. Desmidt ◽

W. Verstraete ◽

J. Dick ◽

B. D. Meesschaert ◽

M. Carballa

Keyword(s):

Hydraulic Retention Time ◽

Ph Value ◽

Continuous Operation ◽

Phosphate Concentration ◽

Phosphate Removal ◽

Synthetic Wastewater ◽

Processing Industry ◽

Operational Conditions ◽

Constant Ph ◽

High Concentrations

In this work, the elimination of phosphate from industrial anaerobic effluents was evaluated at lab-scale. For that purpose, the ureolytic method previously developed for the precipitation of Ca2 + from wastewater as calcite was adapted for the precipitation of phosphate as struvite. In the first part of the study, computer simulations using MAPLE and PHREEQC were performed to model phosphate precipitation from wastewater as struvite. The results obtained showed that relative high concentrations of ammonium and magnesium are needed to precipitate phosphate as struvite. The total molar concentrations ratio of Mg2 + :PO43−-P:NH4+ required to decrease PO43−-P concentrations from 20 to 6 mg PO43−-P/l at pH 8.4-8.5 was estimated on 4.6:1:8. In the second part of the study, lab-scale experiments with either synthetic wastewater or the anaerobic effluent from a vegetable processing industry were carried out in batch and continuous mode. Overall, the continuous operation at a hydraulic retention time (HRT) of 2.4 h and an added molar concentration [Mg2 + ]:[PO43−-P]:[NH4+] ratio of 1.6:1:2.3 resulted in a constant pH value in the reactor (around 8.5) and an efficient phosphate removal (>90%) to residual levels of 1–2 mg PO43−-P/l. Different operational conditions, such as the initial phosphate concentration, HRT and the use of CaCl2 or MgO instead of MgCl2, were analysed and the performance of the reactor was satisfactory under a broad range of them. Yet, overall, optimal results (higher phosphate removal) were obtained with MgCl2.

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Phosphate removal by column packed blast furnace slag ‐ I. Fundamental research by synthetic wastewater

Environmental Technology Letters ◽

10.1080/09593338709384521 ◽

1987 ◽

Vol 8 (1-12) ◽

pp. 589-598 ◽

Cited By ~ 9

Author(s):

Hiroshi Sunahara ◽

Wei Min Xie ◽

Mitsu Kayama

Keyword(s):

Blast Furnace ◽

Blast Furnace Slag ◽

Phosphate Removal ◽

Synthetic Wastewater ◽

Fundamental Research ◽

Furnace Slag

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Immobilized Microalgae using Alginate for Wastewater Treatment

Pertanika Journal of Science and Technology ◽

10.47836/pjst.29.3.34 ◽

2021 ◽

Vol 29 (3) ◽

Author(s):

Amanatuzzakiah Abdul Halim ◽

Wan Nor Atikah Wan Haron

Keyword(s):

Wastewater Treatment ◽

Chlorella Vulgaris ◽

Immobilized Cells ◽

High Energy ◽

Phosphate Removal ◽

Synthetic Wastewater ◽

Nutrients Removal ◽

Removal Rates ◽

Inorganic Substances ◽

Suspended Cells

Organic and inorganic substances are released into the environment because of domestic, agricultural, and industrial activities which contribute to the pollution of water bodies. Removal of these substances from wastewater using conventional treatment involves high energy cost for mechanical aeration to provide oxygen for aerobic digestion system. During this process, the aerobic bacteria rapidly consume the organic matter and convert it into single cell proteins, water, and carbon dioxide. Alternatively, this biological treatment step can be accomplished by growing microalgae in the wastewater. Chlorella vulgaris immobilized in calcium alginate was used to study the removal efficiency of main nutrients in wastewater such as ammonium and phosphate that act as an important factor in microalgae growth. The immobilized cells demonstrated higher percentage of ammonium and phosphate removal of 83% and 79% respectively, compared to free-suspended cells (76% and 56%). COD removal recorded was 89% and 83% for immobilized cells and free-suspended cells, respectively. The kinetics parameters of nutrients removal for immobilized C. vulgaris in synthetic wastewater were also determined. The specific ammonium removal rates (RA) and phosphate removal rates (RP) for Chlorella vulgaris in synthetic wastewater were 8.3 mg.L-1day-1 and 7.9 mg.L-1day-1, respectively. On the other hand, the kinetic coefficient for each nutrient removal determined were kA = 0.0462 L.mg-1 day-1 NH4 and kP = 0.0352 L.mg-1 day-1 PO43-. This study proves the application of immobilized microalgae cells is advantageous to the wastewater treatment efficiency. Furthermore, optimization on the immobilization process can be conducted to further improve the nutrients removal rates which potentially can be applied in the large-scale wastewater treatment process.

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Kinetics of Simultaneous Ammonium and Phosphate Recovery by Natural Zeolite

ChemEngineering ◽

10.3390/chemengineering5040068 ◽

2021 ◽

Vol 5 (4) ◽

pp. 68

Author(s):

Sandro Pesendorfer ◽

Markus Ellersdorfer

Keyword(s):

Ion Exchange ◽

Natural Zeolite ◽

Large Scale ◽

Ph Value ◽

Exchange Process ◽

Phosphate Removal ◽

Synthetic Wastewater ◽

Nutrient Recovery ◽

Phosphate Recovery ◽

Kinetics Of

Nowadays, fertilizers containing nitrogen and phosphorus are indispensable for medium and large-scale industrial agriculture. To meet the growing demand of nutrients and reduce the accompanied ecological footprint of primary fertilizer production, processes and technologies for nutrient recovery are necessary and have to be developed. This study represents the basis of an extension of the ion-exchange-loop-stripping process (ILS), which is a combined stripping and ion exchange process using natural zeolite for nitrogen recovery. In batch experiments with a special zeolite filled stirrer, the mechanism and kinetics of simultaneous ammonium and phosphate recovery by natural zeolite were determined. Zeolite loadings of 6.78 mg PO43− g−1 were reached and after regeneration, phosphate recovery rates up to 75% of the initial concentration were achieved. The speed of phosphate precipitation is mostly controlled by the pH value of synthetic wastewater. Phosphate removal in simultaneous experiments does not affect ammonium sorption onto zeolite. These findings and the different removal mechanisms of ammonium and phosphate lead to versatile applications in wastewater treatment and reveal great potential of natural zeolite in simultaneous nutrient recovery processes.

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Effects of Aeration on Nitrogen and Phosphate Removal with A2O Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.622-623.1738 ◽

2012 ◽

Vol 622-623 ◽

pp. 1738-1741 ◽

Cited By ~ 2

Author(s):

Yong Feng Li ◽

Jian Yu Yang ◽

Guo Cai Zhang

Keyword(s):

Phosphorus Removal ◽

High Efficiency ◽

Low Cost ◽

Significant Decline ◽

Phosphate Removal ◽

Synthetic Wastewater ◽

Nitrogen And Phosphorus ◽

Nitrogen And Phosphorus Removal ◽

System A ◽

Nitrogen And Phosphate Removal

A2O process is shortened form Anaerobic-Anoxic-Aerobic process, which can achieve carbon, nitrogen and phosphate removal, is widely used for its low cost and high efficiency. The Experiment using a 52.15 L anaerobic-anoxic- aerobic (A2O) reactor with simulate synthetic wastewater, by adjusting the aeration of Aerobic units, observing the performance of nitrogen and phosphorus removal under different dissolved oxygen(DO). The result of the whole operation show that the system can not keep a high TN removal efficiency under high aeration, and the low aeration made the system a significant decline in nitrogen and phosphorus removal.

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Removal of Phosphate from Wastewater Using Carbonized Filter Cake

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.879.125 ◽

2018 ◽

Vol 879 ◽

pp. 125-130

Author(s):

Woravith Chansuvarn

Keyword(s):

Contact Time ◽

Filter Cake ◽

Low Cost ◽

Agricultural Waste ◽

Fluorescence Analysis ◽

Phosphate Removal ◽

Synthetic Wastewater ◽

Wastewater Sample ◽

Adsorption Parameters ◽

Phosphate Ion

The aim of this work was to study the potential of the agricultural waste byproduct as a low-cost adsorbent for removal of phosphate ion (PO43-) from synthetic wastewater. The simple preparation of carbonized filter cake (CFC) was performed at 550°C. CFC was also characterized using FTIR, X-ray fluorescence analysis. The adsorptive parameters of batch experiment, such as pH of solution, dosage and contact time were systematically studied in order to the optimization condition. The optimum conditions of pH, contact time and adsorbent dose were to be 6, 60 min, and 2 g/L, respectively. The Langmuir and Freundlich isotherms were used to calculate the adsorption parameters that was able to describe the equilibrium isotherm and adsorptive mechanism. The maximum monolayer adsorption capacity of CFC was estimated as 20.32 mg/g. The optimized condition was applied for phosphate removal from synthetic wastewater. The achieved phosphate removal efficiency from synthetic wastewater sample was to be 92.4%. Filter cake is a low-cost byproduct of sugar cane but it can also highly effective remove phosphate ion from aqueous solution. The modification of filter cake surface via chemical reaction as a new adsorbent in order to increase surface sites and high affinity with phosphate ion will also be further studied.

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Phosphate removal and recovery by a novel electrolytic process

Water Science & Technology ◽

10.2166/wst.2002.0730 ◽

2002 ◽

Vol 46 (11-12) ◽

pp. 147-152 ◽

Cited By ~ 1

Author(s):

Y. Sakakibara ◽

H. Nakajima

Keyword(s):

Electric Current ◽

Removal Rate ◽

Phosphate Concentration ◽

Phosphate Removal ◽

Synthetic Wastewater ◽

Bulk Liquid ◽

Anode Surface ◽

Electrolytic Process ◽

Current Densities ◽

Good Agreement

The possibility of removing and recovering phosphate from wastewater by a novel electrolytic process was investigated experimentally. In the process, ion electrodes are immersed in synthetic wastewater and direct current (DC) is applied to coagulate phosphate on the surface of the anode. Experimental results demonstrated that at electric current densities ranged from 0.001 to 0.1 mA/cm2, phosphate was removed and recovered as phosphate-rich aggregates formed on the anode surface. Decreases in phosphate concentration at bulk liquid were in fairly good agreement with the amounts of phosphate in the aggregates. Moreover, the removal rate of phosphate was increased with increasing electric current. In addition, as heavy metal anions such as Cu2+ deposit on the counter electrode (cathode), it was thought that relatively pure phosphate could be obtained by the present process.

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