Peixia Liang , Huiying Wang , Xinjuan Hu , Mostafa Elshobary , Yi Cui , Bin Zou , Feifei Zhu , Michael Schagerl , Mostafa El-Sheekh , Shuhao Huo
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引用次数: 0
Abstract
This study delves into the impact of varying NH4+-N: NO3−-N ratios in simulated nitrogen-rich wastewater on the physiological and biochemical responses of the Xanthophyceae Tribonema minus. Our findings revealed intriguing patterns: the maximum biomass observed was 5 g/L, which occurred in treatments containing NH4+-N at a concentration of 60 mg/L and NO3−-N at a concentration of 180 mg/L (mass concentration ratio of 1:3). Due to the excessive concentration of NH4+-N, the photosynthetic apparatus is damaged. When NH4+-N exceeds 120 mg/L (ratio 1:1 of NH4+-N: NO3−-N), growth is seriously hindered. However, increased NH4+-N levels foster lipid accumulation. Notably, NH4+-N removal was high across all NH4+-N treatments, ranging from 78 %–90 %. Nitrate, ammonium, and total phosphorus removal declined with increasing NH4+-N proportions due to limited growth of Tribonema minus. When NH4+-N was 120 mg/L (ratio 1:1 of NH4+-N: NO3−-N), the lipid content accounted for 50 % of the biochemical components, surpassing the control group without ammonium addition by 15 %. The lipid composition of T. minus primarily comprises palmitoleic acid, constituting around 50 % of total fatty acids, with its concentration rising at higher NH4+-N supply. Increasing NH4+-N also improved fatty acid profiles and biodiesel properties according to international standards. Overall, this work adds knowledge to stimulate microalgal lipid production. Not only should absolute amounts of nutrients be considered, but also the NH4+-N: NO3−-N ratio to optimize biomass yields with high lipid content.
期刊介绍:
The Journal of Water Process Engineering aims to publish refereed, high-quality research papers with significant novelty and impact in all areas of the engineering of water and wastewater processing . Papers on advanced and novel treatment processes and technologies are particularly welcome. The Journal considers papers in areas such as nanotechnology and biotechnology applications in water, novel oxidation and separation processes, membrane processes (except those for desalination) , catalytic processes for the removal of water contaminants, sustainable processes, water reuse and recycling, water use and wastewater minimization, integrated/hybrid technology, process modeling of water treatment and novel treatment processes. Submissions on the subject of adsorbents, including standard measurements of adsorption kinetics and equilibrium will only be considered if there is a genuine case for novelty and contribution, for example highly novel, sustainable adsorbents and their use: papers on activated carbon-type materials derived from natural matter, or surfactant-modified clays and related minerals, would not fulfil this criterion. The Journal particularly welcomes contributions involving environmentally, economically and socially sustainable technology for water treatment, including those which are energy-efficient, with minimal or no chemical consumption, and capable of water recycling and reuse that minimizes the direct disposal of wastewater to the aquatic environment. Papers that describe novel ideas for solving issues related to water quality and availability are also welcome, as are those that show the transfer of techniques from other disciplines. The Journal will consider papers dealing with processes for various water matrices including drinking water (except desalination), domestic, urban and industrial wastewaters, in addition to their residues. It is expected that the journal will be of particular relevance to chemical and process engineers working in the field. The Journal welcomes Full Text papers, Short Communications, State-of-the-Art Reviews and Letters to Editors and Case Studies