Microalgae Harvesting in a Microfluidic Centrifugal Separator for Enchanced Biofuel Production

Abstract Biofuel is one of the renewable energy resources alternatives to fossil fuels [1]. Among various sources for biofuels, microalgae provide at least three-orders-of-magnitude higher production rate of biodiesel at a given land area than conventional crop-based methods. However, microalgal biodiesel still suffers from significantly lower harvesting performance, making such a fuel less competitive. To increase the separation performance of microalgae from cultivation solution, we used a spiral microchannel that enables the isolation of biofuel-algae particles from water and contaminants contained in the culturing solution. Our preliminary data show that separation performance in the microfluidic centrifugal separator is as high as 88% within a quick separation time of 30 seconds. To optimize separation performance, multiple parameters of algae behaviors and separation techniques were studied and were manipulated to achieve better performance. We found that changing these factors altered the separation performance by increasing or decreasing flocculation, or “clumping” of the microalgae within the microchannels. The important characteristics of the separator geometry, fluid properties, and environmental conditions on algae separation was found and will be further studied in the forthcoming tests. This introductory study reveals that there is an opportunity to improve the currently low performance of algae separation in centrifugal systems using much smaller designs in size, ensuring a much more efficient algae harvesting.

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Bio-Flocculation Property Analyses of Oleaginous Microalgae Auxenochlorella protothecoides UTEX 2341

Sustainability ◽

10.3390/su13052885 ◽

2021 ◽

Vol 13 (5) ◽

pp. 2885

Author(s):

Jinyu Li ◽

Baozhen Li ◽

Jinshui Yang

Keyword(s):

Large Scale ◽

Municipal Wastewater ◽

Biofuel Production ◽

Microalgae Harvesting ◽

Flocculation Efficiency ◽

Oleaginous Microalgae ◽

Freeze Dried ◽

Flocculation Ability ◽

Powder Samples ◽

Auxenochlorella Protothecoides

The bio-flocculation ability of UTEX 2341 was studied for the purpose of improving microalgae harvesting efficiency to cut the high cost of biofuel production. The algae cells of UTEX 2341 cultured under heterotrophic and municipal wastewater conditions were found to have better self-flocculation ability, with flocculation rates of 92% and 85% at 2 h, respectively. Moreover, the flocculation rates of 16 freeze-dried microalgae powder samples cultured under different stress conditions were 0~72% with an algae powder dosage of 35 mg L−1. The flocculation efficiency of DIM, DCd1, DT28, and L6S was stable under different pH of 3~9 and temperatures of 15~50 °C. For samples of IM, LCd0.6, LMn2, and LZn2, the flocculation efficiency decreased or increased respectively with increased pH or temperatures. Though the flocculation properties of the eight samples showed wide differences, their flocculant compositions were almost the same with unknown components occupying large proportions. More studies needed to be further carried out to reveal the flocculation mechanisms and analyze the flocculation abilities in practical application, which would be conducive to future large-scale application of the bio-flocculation method and also cost reduction.

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Peptide-mediated microalgae harvesting method for efficient biofuel production

Biotechnology for Biofuels ◽

10.1186/s13068-015-0406-9 ◽

2016 ◽

Vol 9 (1) ◽

Cited By ~ 17

Author(s):

Yoshiaki Maeda ◽

Takuma Tateishi ◽

Yuta Niwa ◽

Masaki Muto ◽

Tomoko Yoshino ◽

...

Keyword(s):

Biofuel Production ◽

Microalgae Harvesting ◽

Harvesting Method

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Harvesting of Chlorella sp. by Co-cultivation with Some Fil-amentous Fungi

Al-Mustansiriyah Journal of Science ◽

10.23851/mjs.v28i2.497 ◽

2018 ◽

Vol 28 (2) ◽

pp. 35

Author(s):

Rana H. Hameed Al-Shammari

Keyword(s):

Aspergillus Terreus ◽

Research Area ◽

Economic Feasibility ◽

Biofuel Production ◽

Process Time ◽

Microalgae Harvesting ◽

Chlorella Sp ◽

Lower Glucose ◽

Harvesting Process ◽

New Research

Algae are play a major role as straight producers of biofuels, so expansion of a new. harvesting-technology is important to achieve economic feasibility of biofuel production from algae.. Fungal pelletization-assisted.. Microalgal harvesting has Emerged as new research area for decreasing the harvesting cost and energy inputs in the algae-to-biofuel method. The present study tried to opti-mize process circumstances as (substrate inputs, process time and pH). Through choice of a ro-bust fungal strain. Four fungal strains (Aspergillus terreus, Trichoderma sp., Mucor sp. and Rhi-zopus sp.) were screened for their pelletizing efficiency in fresh/supplemented chu-10 with select-ed media nutrient (glucose, nitrogen and phosphorous). Results showed that Aspergillus terreus was the most efficient strain for pelletizing in the nutrient supplemented chu-10 with its neutral pH (7) and acidic pH (5). Stimulatingly, A. terreus was capable to harvest nearly 100 % of the Clorella sp. cells (1×106 spore/ml at optical density (OD) approximately 2.5 initial working algal concentration) within only 24 h. at supplementation of (10 g/l glucose, 2.5 mg/l aNH4NO3 and 0.5 mg/l mK2HPO4) also performed well at lower glucose level (5 g/l) can also results in similar har-vesting but its need relatively higher incubation time. The procedure kinetics in term of harvesting index (H. I) as well as the variation of residual glucose and pH with time was also studied. The mechanism of harvesting process was studied through microscopic, examination. A. terreus strain investigated in this study could emerge as an efficient, sustainable and economically viable tool in microalgae harvesting for biofuel production and time conservation

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Electrochemical harvesting of microalgae꞉ parametric and cost-effectivity comparative investigation

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq191213031a ◽

2020 ◽

pp. 31-31

Author(s):

Atheer Al-Yaqoobi ◽

Muna Al-Rikabey ◽

Mahmood Al-Mashhadani

Keyword(s):

Power Consumption ◽

Comparative Investigation ◽

Biofuel Production ◽

Electrolysis Time ◽

Applied Current ◽

Microalgae Harvesting ◽

Initial Ph ◽

Heavy Burden ◽

Harvesting Efficiency ◽

Harvesting Process

The cost of microalgae harvesting constitutes a heavy burden on the commercialization of biofuel production. The present study addressed this problem through economic and parametric comparison of electrochemical harvesting using a sacrificial electrode (aluminum) and nonsacrificial electrode (graphite). The harvesting efficiency, power consumption, and operation cost were collected as objective variables as a function of applied current and initial pH of the solution. The results indicated that high harvesting efficiency obtained by using aluminum anode is achieved in short electrolysis time. That harvesting efficiency can be enhanced by increasing the applied current or the electrolysis time for both electrodes materials, where 98% of harvesting efficiency can be obtained. The results also demonstrated that the power consumption with graphite anode is higher than that of aluminum. However, at 0.2 A the local cost of operation with graphite (0.036US$/m3), which is distinctly lower than that of aluminum (0.08US$/m3). Furthermore, the harvesting efficiency reached its higher value at short electrolysis time at an initial pH of 6 for aluminum, and at an initial pH of 4 for graphite. Consequently, the power consumption of the harvesting process could be reduced at acid- nature conditions to around 0.46KWh/Kg for aluminum and 1.12KWh/Kg for graphite.

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Enhanced Microalgae Harvesting in a Microfluidic Centrifugal Separator

SSRN Electronic Journal ◽

10.2139/ssrn.3899674 ◽

2021 ◽

Author(s):

Rohan Sharma ◽

Myeongsub Kim

Keyword(s):

Centrifugal Separator ◽

Microalgae Harvesting

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Membranes and Microalgae in Wastewater Treatment

Membrane Technology for Water and Wastewater Treatment in Rural Regions - Practice, Progress, and Proficiency in Sustainability ◽

10.4018/978-1-7998-2645-3.ch012 ◽

2020 ◽

pp. 306-336

Keyword(s):

Wastewater Treatment ◽

Membrane Fouling ◽

Municipal Wastewater ◽

Membrane Bioreactors ◽

Biofuel Production ◽

Co2 Removal ◽

Microalgae Harvesting ◽

Harvesting Process ◽

Carbon Dioxide Co2 ◽

Nitrogen Phosphorus

The application of microalgae-based wastewater treatment was first introduced in the 1940s to treat municipal wastewater. Microalgae have been studied for its various potentials such as for nutrients removal, carbon dioxide (CO2) removal, biofuel production from biomass, etc. This chapter focuses on the potential of microalgae membrane bioreactors for wastewater treatment, microalgae cultivation, and harvesting. Furthermore, the selection of microalgae species is covered by comparison of nitrogen, phosphorus, COD, and BOD removal from various studies. Microalgae membrane bioreactors combine the biological treatment of microalgae with the conventional membrane bioreactor. Still, membrane fouling phenomenon is a challenge in microalgae membrane technology. Thus, several other technologies of immobilized microalgae are introduced which can potentially reduce the membrane fouling occurrence and concurrently remove the need for microalgae harvesting process.

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