Microalgae are product of sustainable development owing to its ability to treat variety of wastewater effluents and thus produced biomass can serve as value added product for various commercial applications. This paper deals with the cultivation of microalgae species namely Chlorella pyrenoidosa and Scenedesmus abundans in rice mill effluent (i.e., paddy soaked water) for nutrient removal. In order to investigate the nutrient removal capability, microalgae are subjected to cultivation in both raw and autoclaved samples. The maximum phosphate removal by Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 98.3% and 97.6%, respectively, whereas, the removal of ammoniacal nitrogen by Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 92% and 90.3%, respectively. The growth (measured in terms of chlorophyll content) of Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 3.88 mg/l and 5.55 mg/l, respectively. The results indicate the suitability of microalgae cultivation in rice mill effluent treatment for nutrient removal. © 2015, Copyright © Taylor &amp; Francis Group, LLC.

Shantha Kumar S

Department of Environmental and Water Resources Engineering

School of Civil Engineering

Vellore Campus

Abinandan S

Bhattacharya R

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Efficacy of Chlorella pyrenoidosa and Scenedesmus abundans for Nutrient Removal in Rice Mill Effluent (Paddy Soaked Water)

International Journal of Phytoremediation

For the exploration of an effective and economical method to treat composite raw tannery effluent, the integrated approach of Ozonation and phycoremediation was followed. In a lab-scale Ozone reactor, the highest performance index was attained, when it was operated at a low O3 flowrate (2 g/h) condition. The tannery effluent partially treated by Ozonation (≈60% COD removed in 90 min) with the ozone consumption of 1.5 g of O3/g of COD, at pH 7.6, coupled with phycoremediation had improved the tannery effluent characteristics to a considerable extent. Overall, the maximum reduction in pollutant concentration attained with the combined treatment was 84% for COD, 60% for colour, 100% for odour, 90% for inorganic carbon, 82% for NH4+- N, 100% for PO4–P, 97% for chromium and 10% for TDS. In phycoremediation, microalgae Nannochloropsis oculata had shown an enhanced growth (μ = 0.255 day−1) with a maximum cell density of 5.2 × 107 cells/mL, dry biomass of 0.86 g L−1 and cell division rate of 0.369 day−1. Elemental analysis of biomass validated the chromium remediation along with other elements such as calcium, magnesium, sodium, potassium, zinc, and iron from the tannery effluent. Therefore, the phycoremediation integrated ozone process can be considered as a feasible treatment method for tannery effluent along with value-added biomass production. © 2020 Elsevier Inc.

Environmental Research

An integrated approach for tannery effluent treatment with ozonation and phycoremediation: A feasibility study

Phycoremediation encompasses microalgae as a sustainable treatment system by integrating the wastewater treatment with bioenergy recovery. However, transforming this technology to real time from lab scale is limited due to temperature and cell volume (inoculum size). Thus, the present study aims to investigate the influence of inoculum size (10%–30% v/v) and temperature condition (25°C–35°C) for the growth of five microalgal species in paddy-soaked wastewater (PSWW), using response surface methodology (RSM). The optimal conditions for better biomass production and wastewater treatment were found to be at 25°C and 30% inoculum size. Among five selected microalgae, Chlorella pyrenoidosa exhibited maximum dry biomass content (831 mg=L) with greater (&gt;90%) removal on ammonical nitrogen (NH3-N) and phosphates (PO4-P) at a rate of 0.025 and 0.006 mg P=mg of dry biomass, respectively, with significant p value (p &lt; 0.05). Similar results were obtained for Chlorella vulgaris and Scenedesmus obliquus (an indigenous sp.) with more than 80% removal efficiency. However, at higher temperatures, Chlorella pyrenoidosa exhibited better results when other strains failed to maintain biomass production and removal on NH3-N and PO4-P. This study demonstrated that phycoremediation is a viable option upon selecting appropriate strains and conditions imminent for scale-up applications. © 2019 American Society of Civil Engineers.

Journal of Environmental Engineering

Optimization of Temperature and Inoculum Size for Phycoremediation of Paddy-Soaked Rice Mill Wastewater

Phycoremediation; biotransformation of nutrients and or pollutants by microalgae, supports sustainable wastewater treatment, coupled with biomass production, resulting in enhanced cost savings, waste minimization, and energy conservation. A major challenge in this technique involves cultivation system to be adopted, mode of treatment and harvesting methods. Three different algal cultivation systems; polybags (PB), photobioreactors (PBR) and race way ponds (RWP) were employed for culturing an indigenous microalga, Scenedesmus obliquus in rice mill paddy-soaked wastewater (PSW). The maximum biomass productivity (BP) of 340 ± 2 mg/L/d was observed in PBR with an ammonical nitrogen (NH3-N) removal (RN) of 96.12 ± 0.21% and the phosphates (PO4-P) removal (RP) of 97.58 ± 0.18%. Highest lipids (L)∼12% (% biomass), protein (P)∼40% and carbohydrates (C)∼20%) were gained in PBR culture system, followed by RWP and PB.

Journal of Environmental Management

Phycoremediation of paddy-soaked wastewater by indigenous microalgae in open and closed culture system

Paddy processing (Rice mill) industries are agro-based industries which discharge wastewater with high organic content, cause nutrient overloading to the environment. Amaranthus palmeri and Sorghum vulgare were used to reduce the excess nutrients from the soil collected from land near a rice mill where wastewater is being disposed. Potted plant experiments were conducted for the selected species and tested for its growth potential and compared with control soil (normal soil). Absolute growth rate (AGR) of 0.52and 1.61 cm/day were obtained for A. palmeri and S. vulgare grown in contaminated soil (APCS and SVCS) which are 2.89 and 1.23 times more than that of the species grown in control soil (APC and SVC), respectively. A positive correlation was observed between AGR and their dry weights (r &gt; 0.685; P = 0.01), and nitrogen removal (r &gt; 0.464; P = 0.01) where it was the negative correlation in phosphate removal (AGR: r &lt; 0.481; P = 0.01; dry weight: r &lt; 0.245; P = 0.05). Significant ANOVA results were obtained for the interaction effect among the species and soil on the nutrient removal efficiency (RE) with respect to AGR and dry weight. It is evident that the both A. palmeri (RE: N = 98.81% and K = 72.32%) and S. vulgare (RE: N = 99.54% and K = 73.23%) are the promising species to remediate the nutrient overloaded soil. © 2018 American Institute of Chemical Engineers Environ Prog, 38: 354–361, 2019. © 2018 American Institute of Chemical Engineers

Environmental Progress & Sustainable Energy

Phytoremediation of nutrient overloaded soil by rice mill wastewater using Amaranthus palmeri and Sorghum vulgare

Efficacy ofChlorella pyrenoidosaandScenedesmus abundansfor Nutrient Removal in Rice Mill Effluent (Paddy Soaked Water)

Bioresource Technology

Two-stage cultivation of two Chlorella sp. strains by simultaneous treatment of brewery wastewater and maximizing lipid productivity

Renewable and Sustainable Energy Reviews

Nutrient recovery from wastewater streams by microalgae: Status and prospects

Trends in Biotechnology

Nitrogen supply is an important driver of sustainable microalgae biofuel production

Applied Microbiology and Biotechnology

Simultaneous nutrient removal and lipid production from pretreated piggery wastewater by Chlorella vulgaris YSW-04

Journal	International Journal of Phytoremediation
Publisher	Informa UK Limited
ISSN	1522-6514
Open Access	0