Enhanced biomass production and nutrient removal efficiency from urban wastewater by Chlorella pyrenoidosa in batch bioreactor system: optimization and model simulation

The bioprospecting of potentially mixotrophic microalgae in a constructed wetland was conducted. A locally isolated microalga, Chlorella sp., was grown to determine the effect of temperature, aeration rate, and cultivation time on simultaneous biomass production and nutrient removal from piggery wastewater using central composite design (CCD). The most important variable for the biomass productivity of Chlorella sp. was aeration rate, while that for lipid content and nutrient removal efficiency was cultivation time. Total nitrogen (TN) and total phosphorus (TP) removal efficiencies were higher than that of chemical oxygen demand (COD) from piggery wastewater. The CCD results indicate that the highest biomass productivity (79.2 mg L−1 d−1) and simultaneous nutrient removal efficiency (TN 80.9%, TP 99.2%, COD 74.5%) were obtained with a cultivation temperature of 25 °C, a cultivation time of 5 days, and an air aeration rate of 1.6 L L−1 min−1. Palmitic acid (C16:0) and linoleic acid (C18:2) were both abundant in Chlorella sp. cells under mixotrophic cultivation with piggery wastewater.

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Nitrogen and phosphorus removal of locally adapted plant species used in constructed wetlands in China

Water Science & Technology ◽

10.2166/wst.2012.200 ◽

2012 ◽

Vol 66 (4) ◽

pp. 695-703 ◽

Cited By ~ 7

Author(s):

Xia Yu ◽

Thomas König ◽

Zhang Qi ◽

Gao Yongsheng

Keyword(s):

Plant Species ◽

Removal Efficiency ◽

Biomass Production ◽

Nutrient Removal ◽

Phosphorus Removal ◽

Ex Situ ◽

Nitrogen And Phosphorus ◽

Nitrogen And Phosphorus Removal ◽

Nutrient Removal Efficiency ◽

Below Ground

This paper assesses the nitrogen and phosphorus removal efficiency of seven plant species (Schoenoplectus lacustris, Vetiveria zizanioides, Acorus calamus, Canna indica, Zizania latifolia, Phragmites communis, and Iris pseudacorus) commonly used in constructed wetland systems in southern China. The investigation considers two aspects that are relevant to determine nutrient removal efficiency: plants’ biomass production and nutrient content in water effluent. Both assessments are correlated with each other. Three different hydraulic retention times with different nutrient loads have been applied in this ex-situ trial. The plants’ biomass production correlates positively with the effluent's nutrient removal efficiency. Six out of seven species reviewed produce more biomass above ground than below ground (average: 67% of dried biomass in aerial part); only I. pseudacorus produces more biomass below ground. S. lacustris, V. zizanioides, I. pseudacorus, and C. indica have performed best in terms of nutrient removal efficiency (65.6–90.2% for nitrogen; 67.7–84.6% for phosphorus).

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Biomass production and nutrient removal efficiency of Suaeda salsa in eutrophic saline water using a floating mat treatment system

Water Science & Technology Water Supply ◽

10.2166/ws.2018.066 ◽

2018 ◽

Vol 19 (1) ◽

pp. 254-263

Author(s):

Chang Yajun ◽

Zhang Ya ◽

Li Naiwei ◽

Liu Xiaojing ◽

Du Fengfeng ◽

...

Keyword(s):

Removal Efficiency ◽

Biomass Production ◽

Nutrient Removal ◽

Saline Water ◽

Salt Content ◽

Biomass Accumulation ◽

High Salt Content ◽

Nutrient Removal Efficiency ◽

Different Levels ◽

Floating Mat

Abstract To explore an economic and practical phytoremediation strategy adapted to remediate hypereutrophic water with high salt content, biomass production and nutrient removal efficiency of Suaeda salsa are determined in eutrophic saline water using a floating mat treatment system. The results suggest that S. salsa, as a pioneer species in coastal tidal flats, has a good ability to tolerate the combined stress of salt and eutrophication under hydroponic conditions, although different levels of salinity have different influence on biomass accumulation. Under optimum-growth saline conditions (274 mM NaCl), the removal efficiency of total nitrogen (TN) and total phosphorus (TP) by S. salsa for hypereutrophic water reaches 73.23% and 72.21%, respectively. The removal efficiency under different levels of eutrophication in the water shows that TN and TP contents in eutrophic saline water are conducive to plant biomass accumulation; the removal efficiency decreases with increasing element concentration. An ecological floating island system suitable for planting S. salsa has been performed and a practical application of S. salsa to remediate eutrophic water resulting from large-scale mariculture carried out. The plant grew well and aquaculture water quality was significantly improved. Therefore, S. salsa could be applied to remediate hypereutrophic water with high salt content.

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Growth and nutrient removal efficiency of duckweed in beef feedlot runoff in laboratory and greenhouse conditions

10.13031/aim.202100934 ◽

2021 ◽

Author(s):

Jacob L Richardson ◽

Andrea M Harris ◽

Mara Zelt ◽

A. M. Schmidt

Keyword(s):

Removal Efficiency ◽

Nutrient Removal ◽

Nutrient Removal Efficiency

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The Optimal Width and Mechanism of Riparian Buffers for Storm Water Nutrient Removal in the Chinese Eutrophic Lake Chaohu Watershed

Water ◽

10.3390/w10101489 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1489 ◽

Cited By ~ 6

Author(s):

Xiuyun Cao ◽

Chunlei Song ◽

Jian Xiao ◽

Yiyong Zhou

Keyword(s):

Removal Efficiency ◽

Nutrient Removal ◽

Eutrophic Lake ◽

Riparian Buffers ◽

Nutrient Level ◽

Nitrification Rate ◽

Lake Chaohu ◽

Potential Nitrification ◽

Different Types ◽

Nutrient Removal Efficiency

Riparian buffers play an important role in intercepting nutrients entering lakes from non-point runoffs. In spite of its ecological significance, little is known regarding the underlying mechanisms of riparian buffers or their optimal width. In this study, we examined nutrient removal efficiency, including the quantity of nutrients and water quality, in the littoral zone of different types of riparian buffers in the watershed around eutrophic Lake Chaohu (China), and estimated the optimal width for different types of riparian buffers for effective nutrient removal. In general, a weak phosphorus (P) adsorption ability and nitrification-denitrification potential in soil resulted in a far greater riparian buffer demand than before in Lake Chaohu, which may be attributed to the soil degradation and simplification of cover vegetation. In detail, the width was at least 23 m (grass/forest) and 130 m (grass) for total P (TP) and total nitrogen (TN) to reach 50% removal efficiency, respectively, indicating a significantly greater demand for TN removal than that for TP. Additionally, wetland and grass/forest riparian buffers were more effective for TP removal, which was attributed to a high P sorption maximum (Qmax) and a low equilibrium P concentration (EPC0), respectively. The high potential nitrification rate (PNR) and potential denitrification rate (PDR) were responsible for the more effective TN removal efficiencies in grass riparian buffers. The nutrient removal efficiency of different types of riparian buffers was closely related with nutrient level in adjacent littoral zones around Lake Chaohu.

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