Agroindustrial Wastewater Treatment with Simultaneous Biodiesel Production in Attached Growth Systems Using a Mixed Microbial Culture

The use of cyanobacteria in biological wastewater treatment technologies can greatly reduce operation costs by combining wastewater bioremediation and production of lipid suitable as biodiesel feedstock. In this work, an attached growth system was employed to achieve the above-mentioned dual objective using a mixed microbial culture dominated by Leptolyngbya and Limnothrix species in diverse heterotrophic consortia. Kinetic experiments on different initial pollutant concentrations were carried out to determine the ability of the established culture to remove organic load (expressed by d-COD, dissolved-Chemical Oxygen Demand), N and P from agroindustrial wastewaters (dairy, winery and raisin). Biomass and oil productivity were determined. It was found that significant removal rates of nutrients were achieved in all the wastewaters examined, especially in that originated from winery in which the highest d-COD removal rate (up to 97.4%) was observed. The attached microbial biomass produced in winery wastewater contained 23.2% lipid/biomass, wt/wt, which was satisfying. The growth in the dairy wastewater yielded the highest attached biomass productivity (5.03 g m−2 day−1) followed by the mixed effluent of winery-raisin (4.12 g m−2 day−1) and the winery wastewater (3.08 g m−2 day−1). The produced microbial lipids contained high percentages of saturated and mono-unsaturated fatty acids (over 89% in total lipids) in all substrates examined. We conclude that the proposed attached growth photobioreactor system can be considered an effective wastewater treatment system that simultaneously produces microbial lipids suitable as biodiesel feedstock.

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Lipid and biodiesel production by cultivation isolated strain Chlorella sorokiniana pa.91 and Chlorella vulgaris in dairy wastewater treatment plant effluents

Journal of Environmental Health Science and Engineering ◽

10.1007/s40201-020-00483-y ◽

2020 ◽

Vol 18 (2) ◽

pp. 573-585

Author(s):

Pariya Asadi ◽

Hassan Amini Rad ◽

Farhad Qaderi

Keyword(s):

Wastewater Treatment ◽

Chlorella Vulgaris ◽

Wastewater Treatment Plant ◽

Treatment Plant ◽

Chlorella Sorokiniana ◽

Dairy Wastewater ◽

Biodiesel Production

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The untapped industrial crop, Cucumeropsis mannii: dry oil extraction, characterization and potential use as biodiesel feedstock and heavy metal sink

Sustainable Environment Research ◽

10.1186/s42834-021-00082-y ◽

2021 ◽

Vol 31 (1) ◽

Author(s):

Onyeka Stanislaus Okwundu ◽

Chimezie John Chiama ◽

Chinedu James Chiama ◽

Pius Charles Ucheagwu ◽

Ekene Kingsley Uzoma ◽

...

Keyword(s):

Heavy Metal ◽

Wastewater Treatment ◽

Metal Removal ◽

Heavy Metal Removal ◽

Oxidation Stability ◽

Biodiesel Production ◽

Heterogeneous Nanocatalyst ◽

Biodiesel Feedstock ◽

Cucumeropsis Mannii ◽

Potential Use

AbstractDue to the quest to meet a basic need – food, vast potentials of numerous African crops have remained unexplored. Cucumeropsis mannii, an invaluable West African melon, is cultivated for its edible proteinous oil-rich seeds. Here, we report for the first time, its potential use for biodiesel production over an uncommon heterogeneous nanocatalyst, and for wastewater treatment. An identification of the untapped species’ seed was made, for disambiguation. Oil (CMO) was expressed from the C. mannii seeds (CMS) and characterized. The CMS was found composed of 53.5% lipids, while 46.1% of the full-fat CMS flour was recovered as vegetable oil. Transesterification experiments were performed using a specially-prepared heterogeneous nanocatalyst derived from Eobania vermiculata shells, by varying successively: methanol/oil ratio, temperature, and reaction time. Maximum biodiesel (CMOME) yield of 86.2% was achieved at catalyst concentration of 5.4%, methanol to oil molar ratio of 9:1, reaction temperature of 60 °C, after 3 h of reaction. Furthermore, part of the polyunsaturated CMO was sulphur-functionalized and utilized at different dosage levels for extraction of Ag+ from 600 to 1500 ppm simulated water. The modified CMO exhibited desirable sorption properties – sinking 100% of Ag+ from 900 ppm water, after 7-h-phase-contact at 6.9 g (20 mL)− 1 dosage. Stagewise operation (multi-staging) was found capable of improving the extraction efficiency in highly concentrated wastewater. Although CMOME conformed to EN-14214 and ASTM D-6751 standards, it had low oxidation stability; making wastewater treatment a more faithful application. Regarding the crop’s food value, residual CMS cake remained edible, even with longer shelf-life (relative to the full-fat flour) – encouraging commercial flour-defattening and consequent availability of CMO for industrial applications. Lastly, it was concluded (with some relevant recommendations) that CMO has great potentials for use as biodiesel feedstock and as heavy metal removal agent.

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AN APPROACH ON ATTACHED GROWTH PROCESS FOR DOMESTIC WASTEWATER TREATMENT

Environmental Engineering and Management Journal ◽

10.30638/eemj.2014.018 ◽

2014 ◽

Vol 13 (1) ◽

pp. 145-152 ◽

Cited By ~ 1

Author(s):

Alireza Valipour ◽

Seyed Masoud Taghvaei ◽

Venkatraman Kalyan Raman ◽

Gagik Badalians Gholikandi ◽

Shervin Jamshidi ◽

...

Keyword(s):

Wastewater Treatment ◽

Growth Process ◽

Domestic Wastewater ◽

Attached Growth ◽

Domestic Wastewater Treatment

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Experience with nutrient removal in a fixed-film system at full-scale wastewater treatment plants

Water Science & Technology ◽

10.2166/wst.1997.0030 ◽

1997 ◽

Vol 36 (1) ◽

pp. 129-137 ◽

Cited By ~ 7

Author(s):

Vibeke R. Borregaard

Keyword(s):

Wastewater Treatment ◽

Surface Area ◽

Nutrient Removal ◽

Wastewater Treatment Plants ◽

High Specific Surface Area ◽

Biological Nutrient Removal ◽

Growth Processes ◽

Total N ◽

Attached Growth ◽

On Line

In the upgrade of wastewater treatment plants to include biological nutrient removal the space available is often a limiting facor. It may be difficult to use conventional suspended growth processes (i.e. activated sludge) owing to the relatively large surface area required for these processes. Recent years have therefore seen a revived interest in treatment technologies using various types of attached growth processes. The “new” attached growth processes, like the Biostyr process, utilise various kinds of manufactured media, e.g. polystyrene granules, which offer a high specific surface area, and are therefore very compact. The Biostyr plants allow a combination of nitrification-denitrification and filtration in one and the same unit. The results obtained are 8 mg total N/l and an SS content normally below 10 mg/l. The plants in Denmark which have been extended with a Biostyr unit have various levels of PLC control and on-line instrumentation.

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Characterization of Nostoc muscorum NCCU-442 Derived Poly-3- hydroxybutyrate (PHB) and Polyethylene Glycol (PEG) Blends

The Natural Products Journal ◽

10.2174/2210315508666180810145127 ◽

2020 ◽

Vol 10 (3) ◽

pp. 200-207

Author(s):

Sabbir Ansari ◽

Tasneem Fatma

Keyword(s):

Thermal Properties ◽

Polyethylene Glycol ◽

Morphological Properties ◽

Morphological Alteration ◽

Nostoc Muscorum ◽

Microbial Culture ◽

Polymer Science ◽

Mixed Microbial Culture ◽

Scanning Calorimetry ◽

Casting Technique

Background: Poly-3-hydroxybutyrate (PHB) has attracted much consideration as biodegradable biocompatible polymer. This thermoplastic polymer has comparable material properties to polypropylene. Materials with more valuable properties may result from blending, a common practice in polymer science. Objective: In this paper, blends of PHB (extracted from cyanobacterium Nostoc muscorum NCCU- 442 with polyethylene glycol (PEG) were investigated for their thermal, tensile, hydrophilic and biodegradation properties. Methods: Blends were prepared in different proportions of PHB/PEG viz. 100/0, 98/2, 95/5, 90/10, 80/20, and 70/30 (wt %) using solvent casting technique. Morphological properties were investigated by using Scanning Electron Microscopy (SEM). Differential scanning calorimetry and thermogravimetric analysis were done for thermal properties determination whereas the mechanical and hydrophilic properties of the blends were studied by means of an automated material testing system and contact angle analyser respectively. Biodegradability potential of the blended films was tested as percent weight loss by mixed microbial culture within 60 days. Results: The blends showed good misciblity between PEG and PHB, however increasing concentrations of plasticizer caused morphological alteration as evidenced by SEM micrographs. PEG addition (10 % and above) showed significant alternations in the thermal properties of the blends. Increase in the PEG content increased the elongation at break ratio i.e enhanced the required plasticity of PHB. Rate of microbial facilitated degradation of the blends was greater with increasing PEG concentrations. Conclusion: Blending with PEG increased the crucial polymeric properties of cyanobacterial PHB.

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