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Number of results: 9
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Abstract

The production of biofuels using wastewater as a microalgae culture medium is a little explored technology, but with potential for success. In order to contribute to the knowledge of these technologies and their technical feasibility for microalgae growth, in this work the Chlorella sp. strain was cultivated in two types of effluents generated in an experimental farm located in eastern Colombia, before and after a biological treatment process. The consumption of the main nutrients that regulate growth and lipid production was evaluated, in order to extract, quantify, characterize and convert them into biodiesel. The results showed that Chlorella sp. growth and lipid production is more favourable in R2 medium of treated water than in R1 medium of raw water, mainly due to phosphorus limitation and higher N-NO3 concentration in R2 compared to R1. In the R2 medium culture, a percentage of 42.54% of long-chain fatty acids was found, which is necessary to obtain a high quality biodiesel. Finally, the best transesterification experiment allowed reaching a fatty acid methyl esters (FAME) percentage of 90.1 ± 2.7%. In general, the results demonstrated the potential viability of using the wastewater generated in the San Pablo farm to produce biomass with lipid content to obtain biodiesel, finding that where the concentration of nutrients, mainly nitrogen, has a great influence on the microalgal metabolism for lipid accumulation.
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Authors and Affiliations

Nestor Andres Urbina-Suarez
1
ORCID: ORCID
Andres Fernando Barajas-Solano
1
ORCID: ORCID
Janet Bibiana Garcia-Martinez
1
ORCID: ORCID
German Luciano Lopez-Barrera
1
ORCID: ORCID
Angel Dario Gonzalez-Delgado
2
ORCID: ORCID

  1. Francisco de Paula Santander University, Cúcuta, Colombia
  2. University of Cartagena, Avenida del Consulado Calle 30 No. 48-152, Cartagena, Bolívar, Colombia
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Abstract

The aim of the paper is to present the hydrodynamic, mass transfer and illumination characteristics of a laboratory helical-tube photobioreactor Biostat PBR-2S, commercially available and used in many laboratories in Poland and worldwide. The investigated hydrodynamics parameters were: mean liquid circulation rate, liquid velocity/residence time in the tubular part of the apparatus and mixing time, measured in the wide range of rotary speed of the circulation pump. The influence of the aeration intensity on these parameters was also checked. The volumetric oxygen and carbon dioxide transfer coefficients in the liquid phase and their dependency on the liquid circulation rate and gas inflow rate were determined. The experiments were performed in tap water and then in a real three-phase cultivation broth at the end of thermophilic cyanobacteria T. synechococus growth. For the final evaluation of the tested PBR there were series of test cultivations run under different conditions of illumination. The highest final concentration of the biomass of tested cyanobacteria reached the relatively high value of 4.38 g/dm3 of the dry biomass, although the process conditions were not fully optimized. The laboratory photobioreactor PBR-2S proved to be a good tool for investigations of microalgae cultivation processes. The presented results and practical observations may help to analyze and understand the mutual influence of the specific process parameters in the described PBR, especially during autotrophic organism cultivations.

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Authors and Affiliations

Paweł Gluszcz
Anna Klepacz-Smółka
Stanisław Ledakowicz
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Abstract

When and where did life first appear on Earth? Humankind has been pondering this question for centuries. The discovery of ancient microalgae is providing a partial answer.

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Authors and Affiliations

Józef Kaźmierczak
Barbara Kremer
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Abstract

This study investigated the potential of three microalgae taxonomic groups of Chlorophyta, Cyanoprokaryota and Bacillariophyceae for biogas production. Biogas potential was assessed in mesophilic anaerobic digestion batch tests over a period of 20 days. The cumulative biogas yield (CBY) of Chlorophyta and Cyanoprocaryota was respectively 396.21 mL/g Volatile Solids (VS) and 382.45 mL/g VS. Bacillariophyceae digestion showed lower biogas production of 357.07 mL/g VS. The highest cumulative methane yield (CMY) of 241.25 mL CH 4/g VS was recorded for Cyanoprocaryota biomass, which was signifi cantly higher (p<0.05) than the other two types of microalgae. The highest methane content in biogas of 63.08% was observed with Cyanoprokaryota. Chemical composition of biomass as well as biogas productivity are infl uenced by algal taxonomy.
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Authors and Affiliations

Marta Kisielewska
1
Marcin Dębowski
1
Marcin Zieliński
1

  1. Uniwersytet Warmińsko-Mazurski w Olsztynie, Department of Environmental Engineering
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Abstract

In recent years, the technical and economic feasibility of using microalgae and cyanobacteria has been explored for the removal and exploitation of domestic, agricultural and industrial residual effluents with high C, N and P compounds content. To contribute to the understanding of the process and its technical viability for microalgae growth, the article discusses monitoring, flow determination, and physicochemical characteristics of two types of effluents generated in an experimental farm located in the east of Colombia, before (R1) and after biological treatment (R2). In general, the results showed the reduction of different parameters, such as total dissolved solids (TDS), hardness, salinity and phosphates after treatment with activated sludge. However, the conductivity value obtained in R1 and R2 showed the presence of a pollutant load. These findings can be attributed to the highest concentration of fats and oils in the water during early hours of the day. Finally, although the concentration of nitrates increased from 46.63 to 225.21 mg∙dm–3 and phosphate decreased slightly from 9.65 to 6.21 mg∙dm–3, no inhibition was generated in the microalgae, as evidenced in the growth of the microalgal biomass in effluents after nitrate and phosphate removal above 80%.
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Authors and Affiliations

Nestor Andres Urbina-Suarez
1
ORCID: ORCID
Andres Fernando Barajas-Solano
1
ORCID: ORCID
Janet Bibiana Garcia-Martinez
1
ORCID: ORCID
German Luciano Lopez-Barrera
1
ORCID: ORCID
Angel Dario González-Delgado
2
ORCID: ORCID

  1. Universidad Francisco de Paula Santander, Faculty of Agricultural and Environmental Sciences, San José de Cúcuta, Colombia
  2. University of Cartagena, Avenida del Consulado Calle 30 No. 48-152, Cartagena, Bolívar, 130001, Colombia
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Abstract

The present study is aimed to access the growth rates, biomass productivity and nutrient removal in different concentrations of microalgae Botryococcus sp. beads using kitchen wastewater as a media. Verhulst logistic kinetic model was used to measure the optimal concentrations of microalgae Botryococcus sp. in kitchen wastewater in terms of cell growth rate kinetics and biomass productivity. The study verified that the maximum productivity was recorded with 1×106 cell/ml of the initial concentration of Botryococcus sp. with 42.64 mg/l/day and the highest removal of tp and ammonia was obtained (78.14% and 60.53% respectively). The highest specific growth rate of biomass at 0.2896 μmax/d compare to other concentrations, while the lowest occurred at concentrations of 105 cells/ml at 0.0412 μmax/d. The present study shows the different concentrations of Botryococcus sp. in alginate beads culturing in kitchen wastewater influence the cells growth of biomass and nutrient uptake with optimum concentration (106 cells/ml) of Botryococcus sp. which is suggested for wastewater treatment purposes. The result of scanning electron microscopy (sem) shows differences in morphology in terms of surface; smoother and cleaner (before the experiment), cracks and rough surface with black/white spots (after the experiment). These findings seemly can be applied efficiently in kitchen wastewater treatment as well as a production medium for microalgae biomass.
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Authors and Affiliations

N.A.R. Shaari
1
N.M. Apandi
1 2
ORCID: ORCID
N.M. Sunar
3
ORCID: ORCID
R. Nagarajah
1
K. Cheong
1
S.S.M. Ahia
1
Khairul Anwar Abdul Halim
4
ORCID: ORCID
M. Gacek
5
ORCID: ORCID
Wan Mastura Wan Ibrahim
4
ORCID: ORCID

  1. Universiti Tun Hussein Onn Malaysia Faculty Of Engineering Technology, Department of Civil Engineering Technology, Pagoh Education Hub, 84600, Pagoh, Muar, Johor, Malaysia
  2. Universiti Tun Hussein Onn Malaysia, Susta Inable Engineering Technology Research Centre (Setechrc), Faculty of Civil Engineering Technology, Pagoh Educat Ion Hub, 84600, Pagoh, Muar, Johor, Malaysia
  3. Universiti Tun Hussein Onn Malaysia, Research Centre for Soft Soil (Recess), Institute of Integrat Edengineering, 86400 Batu Pahat , Johor, Malaysia
  4. Universiti Malaysia Perlis (Unimap), Centre of Excellence Geopolymer & Green Technology (Cegeogtech), 01000 Perlis, Malaysia
  5. Czestochowa University of Technology, Faculty of Production Engineering And Materials Technology. Department of Physics, 19 Armii Krajowej Av., 42-200 Czestochowa , Poland
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Abstract

Density, composition and domination structure of the sea ice microalgae in the Admiralty Bay (South Shetland Islands) were investigated in 1983. Algae were recorded both in discoloured and in colourless sea ice from June to October. The highest algae density, amounting to 5 x 105 cells in 1 cm3 was observed till the end of August, the diatoms Nitzschia cylindrus and N. curta being the dominant species. A total of 95 algal taxa. mostly diatoms, were recorded. Air temperature seems to be an important factor influencing the development of algae in sea ice.

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Authors and Affiliations

Ryszard Ligowski
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Abstract

The paper focused on the co-production of high-value-added product thermostable C-phycocyanin (C-PC) and biomass, further utilized in pyrolysis. The photobiosynthesis of CPC was carried out by the thermophilic cyanobacteria Synechococcus PCC6715 cultivated in the helical and flat panel photobioreactors (PBR). Despite the application of different inorganic carbon sources, both PBRs were characterized by the same growth efficiency and similar C-PC concentration in biomass. To release the intracellular C-PC the biomass was concentrated and disintegrated by the freeze-thaw method. The crude C-PC was then further purified by foam fractionation (FF), aqueous two-phase extraction (ATPE), membrane techniques (UF) and fast protein liquid chromatography (FPLC). Each of the tested methods can be used separately; however, from a practical and economic point of view, a three-stage purification system (FF, FPLC and UF) was proposed. The purity ratio of the final C-PC was about 3.9, which allows it to be classified as a reactive grade. To improve the profitability of 3G biorefinery, the solid biomass residue was used as a substrate to pyrolysis process, which leads to production of additional chemicals in the form of oils, gas (containing e.g. H 2) and biochar.
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Authors and Affiliations

Stanisław Ledakowicz
1
ORCID: ORCID
Anna Antecka
1
ORCID: ORCID
Pawel Gluszcz
1
ORCID: ORCID
Anna Klepacz-Smolka
1
ORCID: ORCID
Damian Pietrzyk
1
Rafal Szelag
1
Radoslaw Slezak
1
ORCID: ORCID
Maurycy Daroch
2
ORCID: ORCID

  1. Lodz University of Technology, Faculty of Process and Environmental Engineering, Department of Bioprocess Engineering, Wolczanska 213, 93-005 Lodz, Poland
  2. School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
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Abstract

Exposure of green algae Chlorella vulgaris to short-term UV-B radiation (280 nm – 315 nm) induced several changes in the function of photosystem II (PS II) studied by means of chlorophyll fluorescence (FL) and oxygen evolving. The intensity of photosynthetic oxygen evolving intensity of algae suspension decreased in a similar way to the FL parameter values in proportion to the applied dose of UV-B radiation (0.0, 3.2, 6.4, 12.8 kJ·m-2). The correlation between photosynthetic oxygen evolving intensity and FV/FO ratio was better than that between photosynthetic oxygen evolving intensity and FV/FM. The vitality index (Rfd) in the UV-B irradiated algae strongly decreased, compared to the control, which indicates inhibition of potential CO2 fixation and cooperation between light and dark reactions of photosynthesis. It may indicate damage of Rubisco.
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Authors and Affiliations

Elżbieta Skórska
Antoni Murkowski

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