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Author (up) Cabrera, F.; Torres, A.; Campos, J.L.; Jeison, D.
Title Effect of Operational Conditions on the Behaviour and Associated Costs of Mixed Microbial Cultures for PHA Production Type
Year 2019 Publication Polymers Abbreviated Journal Polymers
Volume 11 Issue 2 Pages 14 pp
Keywords PHA; mixed microbial cultures; bioplastics; feast-famine; cost
Abstract Massive production and disposal of petrochemical derived plastics represent relevant environmental problems. Polyhydroxyalkanoates (PHA) are a renewable alternative that can even be produced from wastes. The production of PHA from acetate using mixed microbial cultures was studied. The effect of two key operational conditions was evaluated, i.e., substrate concentration and cycle length. The effects of these factors on several responses were studied using a surface response methodology. Several reactors were operated under selected conditions for at least 10 solids retention times to ensure stable operation. Results show that conditions providing higher PHA content involve lower biomass productivities. This has a great impact on biomass production costs. Results suggest then that PHA content alone may not be a reasonable criterion for determining optimal conditions for PHB production. If production costs need to be reduced, conditions that provide a lower PHA content in the selection reactor, but a higher biomass productivity may be of interest.
Address [Cabrera, Francisco; Torres, Alvaro] Univ La Frontera, Dept Chem Engn, Ave Francisco Salazar 01145, Temuco 4780000, Chile, Email: f.cabrera01@ufromail.cl;
Corporate Author Thesis
Publisher Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2073-4360 ISBN Medium
Area Expedition Conference
Notes WOS:000460296000005 Approved
Call Number UAI @ eduardo.moreno @ Serial 986
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Author (up) Cabrera, F.; Torres-Aravena, A.; Pinto-Ibieta, F.; Campos, J.L.; Jeison, D.
Title On-Line Control of Feast/Famine Cycles to Improve PHB Accumulation during Cultivation of Mixed Microbial Cultures in Sequential Batch Reactors Type
Year 2021 Publication International Journal of Environmental Research and Public Health Abbreviated Journal Int. J. Environ. Res. Public Health
Volume 18 Issue 23 Pages 12611
Keywords PHB; bioplastics; SBR; dissolved oxygen; feast; famine
Abstract Production of polyhydroxyalkanoates (PHA) has generated great interest as building blocks for bioplastic production. Their production using mixed microbial cultures represents an interesting alternative, since it enables the use of organic wastes as a carbon source. Feast/famine strategy is a common way to promote selection of microorganisms with PHA accumulation capacity. However, when using waste sources, changes in substrate concentration are expected, that may affect performance and efficiency of the process. This study showed how the dissolved oxygen level can be used for online control of the cycle time, ensuring that the desired feast/famine ratio is effectively applied. An operation strategy is presented and validated, using sequential batch reactors fed with acetate as the carbon source. Production of polyhydroxybutyrate (PHB) was studied, which is the expected type of PHA to be synthetized when using acetate as substrate. Two reactors were operated by applying the proposed control strategy, to provide F/F ratios of 0.2 and 0.6, respectively. A third reactor was operated with a fixed cycle time, for comparison purposes. Results showed that the reactor that operated at an F/F ratio of 0.6 promoted higher biomass productivity and PHB content, as a result of a better use of available time, preventing unnecessary long famine times. The application of the tested strategy is a simple a reliable way to promote a better performance of feast/famine-based bioreactors involving mixed microbial cultures for PHB production.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1660-4601 ISBN Medium
Area Expedition Conference
Notes WOS:000734924900001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1523
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Author (up) Crutchik, D.; Franchi, O.; Caminos, L.; Jeison, D.; Belmonte, M.; Pedrouso, A.; Val del Rio, A.; Mosquera-Corral, A.; Campos, J.L.
Title Polyhydroxyalkanoates (PHAs) Production: A Feasible Economic Option for the Treatment of Sewage Sludge in Municipal Wastewater Treatment Plants? Type
Year 2020 Publication Water Abbreviated Journal Water
Volume 12 Issue 4 Pages 12 pp
Keywords anaerobic digestion; bioplastics; economic analysis; methane; resource recovery; sewage sludge; WWTP size
Abstract Sludge is a by-product of municipal wastewater treatment plants (WWTPs) and its management contributes significantly to the operating costs. Large WWTPs usually have anaerobic sludge digesters to valorize sludge as methane and to reduce its mass. However, the low methane market price opens the possibility for generating other high value-added products from the organic matter in sludge, such as polyhydroxyalkanoates (PHAs). In this work, the economic feasibility of retrofitting two types of WWTPs to convert them into biofactories of crude PHAs was studied. Two cases were analyzed: (a) a large WWTP with anaerobic sludge digestion; and (b) a small WWTP where sludge is only dewatered. In a two-stage PHA-production system (biomass enrichment plus PHAs accumulation), the minimum PHAs cost would be 1.26 and 2.26 US$/kg PHA-crude for the large and small WWTPs, respectively. In a single-stage process, where a fraction of the secondary sludge (25%) is directly used to accumulate PHAs, the production costs would decrease by around 15.9% (small WWTPs) and 19.0% (large WWTPs), since capital costs associated with bioreactors decrease. Sensitivity analysis showed that the PHA/COD (Chemical Oxygen Demand) yield is the most crucial parameter affecting the production costs. The energy, methane, and sludge management prices also have an essential effect on the production costs, and their effect depends on the WWTP's size.
Address [Crutchik, Dafne; Franchi, Oscar; Caminos, Luis; Luis Campos, Jose] Univ Adolfo Ibanez, Fac Engn & Sci, Ave Padre Hurtado 750, Vina Del Mar 2520000, Chile, Email: dafne.crutchik@uai.cl;
Corporate Author Thesis
Publisher Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2073-4441 ISBN Medium
Area Expedition Conference
Notes WOS:000539527500195 Approved
Call Number UAI @ eduardo.moreno @ Serial 1189
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Author (up) Crutchik, D.; Franchi, O.; Jeison, D.; Vidal, G.; Pinto, A.; Pedrouso, A.; Campos, J.L.
Title Techno-Economic Evaluation of Ozone Application to Reduce Sludge Production in Small Urban WWTPs Type
Year 2022 Publication Sustainability Abbreviated Journal Sustainability
Volume 14 Issue 5 Pages 2480
Keywords disintegration process; ozonations; ludge reductions; ludge retention time
Abstract In Chile, small wastewater treatment plants (WWTPs) (treatment capacity of less than 4,800 m(3)/d) are normally not designed with consideration for the potential valorization of generated sludge. For this reason, they are generally operated at high solids residence times (SRT) (15 d) to promote the decay of biomass, promoting less sludge production and reducing the costs associated with biomass management. Operation at high SRT implies the need for a larger activated sludge system, increasing capital costs. The implementation of a sludge-disintegration unit by ozonation in future WWTPs could enable operation at an SRT of 3 d, with low sludge generation. In this work, we evaluate how the implementation of a sludge-ozonation system in small WWTPs (200-4000 m(3)/d) would affect treatment costs. Four scenarios were studied: (1) a current WWTP operated at an SRT of 15 d, without a sludge ozonation system; (2) a WWTP operated at an SRT of 15 d, with a sludge-ozonation system that would achieve zero sludge production; (3) a WWTP operated at an SRT of 3 d, with a sludge-ozonation system that would provide the same sludge production as scenario 1; (4) a WWTP operated at an SRT of 15 d, with a sludge-ozonation system that would achieve zero sludge production. Economic analysis shows that the treatment costs for scenarios 1 and 2 are similar, while a reduction in cost of up to 47% is obtained for scenarios 3 and 4.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2071-1050 ISBN Medium
Area Expedition Conference
Notes WOS:000916946500001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1722
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Author (up) Vergara, C.; Munoz, R.; Campos, J.L.; Seeger, M.; Jeison, D.
Title Influence of light intensity on bacterial nitrifying activity in algal-bacterial photobioreactors and its implications for microalgae-based wastewater treatment Type
Year 2016 Publication International Biodeterioration & Biodegradation Abbreviated Journal Int. Biodeterior. Biodegrad.
Volume 114 Issue Pages 116-121
Keywords Nitrification; Ammonium oxidizer; Nitrite oxidizer; Microalgal-bacterial consortium; Photobioreactor; Photoinhibition; Wastewater treatment
Abstract The influence of irradiance on the nitrifying activity in photobioreactors of a bacterial consortium enriched from a wastewater treatment bioreactor was assessed using independent ammonium oxidation kinetic batch tests and respirometric assays. Culture irradiance below 250 μmol m(-2) s(-1) did not show a significant effect on nitrification activity, while irradiance at 500 and 1250 μmol m(-2) s(-1) caused a decrease of 20 and 60% in the specific total ammonium nitrogen removal rates and a reduction of 26 and 71% in the specific NO3- production rates, respectively. However, no significant influence of irradiance on the affinity constant of NH4+ oxidation was observed. The increasing nitrite accumulation at higher light intensities suggested a higher light sensitivity of nitrite oxidizers. Additionally, NH4+ oxidation respirometric assays showed a decrease in the oxygen uptake of 14 and 50% at 500 and 1250 μmol m(-2) s(-1), respectively. The experimental determination of the light extinction coefficient (lambda) of the nitrifying bacterial consortium (lambda = 0.0003 m(2) g(-1)) and of Chlorella sorokiniana (lambda = 0.1045 m(2) g(-1)) allowed the estimation of light penetration in algal-bacterial high rate algal ponds, which showed that photo inhibition of nitrifying bacteria can be significantly mitigated in the presence of high density microalgal cultures. 2016 Elsevier Ltd. All rights reserved.
Address [Vergara, C.; Jeison, D.] Univ La Frontera, Dept Chem Engn, Francisco Salazar 01145, Temuco, Chile, Email: christian.vergara@ufrontera.cl
Corporate Author Thesis
Publisher Elsevier Sci Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0964-8305 ISBN Medium
Area Expedition Conference
Notes WOS:000383528000016 Approved
Call Number UAI @ eduardo.moreno @ Serial 657
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Author (up) Zuniga-Barra, H.; Ortega-Martinez, E.; Toledo-Alarcon, J.; Torres-Aravena, A.; Jorquera, L.; Rivas, M.; Jeison, D.
Title Potential Use of Microbially Induced Calcite Precipitation for the Biocementation of Mine Tailings Type
Year 2023 Publication Minerals Abbreviated Journal Minerals
Volume 13 Issue 4 Pages 506
Keywords Microbially induced calcite precipitation; tailing; biocementation; calcium carbonate; Sporosarcina pasteurii
Abstract Mining activities offer clear economic benefits for mineral-rich countries. However, mining operations can produce several environmental impacts. Many of these are associated with generating and managing mining waste known as tailings, which are typically stored in surface facilities. Windblown dust emissions from tailing deposits can cause severe damage to local ecosystems and adverse health effects for the surrounding population. Microbially induced calcite precipitation (MICP) can be used for the superficial biocementation of tailings, thereby preventing such emissions. This research studied the capacity of MICP for the biocementation of tailings. The effect of applying different doses of biocementation reagents and two different methods for their application were evaluated. Results show that a relevant increase in surface strength can be achieved, especially if reagents are mechanically mixed with the tailings to induce a more homogeneous distribution of precipitates. Micrographical and mineralogical analysis by SEM, FTIR and XRD analysis showed the precipitation of calcium in the form of anorthite, calcite or vaterite. Overall results indicate that calcite precipitation can be induced in tailing by microorganisms with urease activity, providing a potential technique for the biocementation of this material.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2075-163X ISBN Medium
Area Expedition Conference
Notes WOS:000977188100001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1829
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Author (up) Zuniga-Barra, H.; Toledo-Alarcon, J.; Torres-Aravena, A.; Jorquera, L.; Rivas, M.; Gutierrez, L.; Jeison, D.
Title Improving the sustainable management of mining tailings through microbially induced calcite precipitation: A review Type
Year 2022 Publication Minerals Engineering Abbreviated Journal Miner. Eng.
Volume 189 Issue Pages 107855
Keywords Microbially induced calcite precipitation(MICP); Tailings; Mining industry; Calcite; Precipitation; Environment
Abstract Mining activities offers evident potential economic benefits for mineral rich countries. However, mining operations can produce a series of environmental impacts. Many of them are associated with the generation and management of tailings. Biogeochemical processes have potential to modify the properties of particulate solids, such as tailings. Microbial induced calcite precipitation (MICP) is probably the most studied biogeochemical process. It promotes calcite precipitation, as a result of biological activity of different microorganisms. Available research indicates that MICP is a tool that has the potential to contribute to a more sustainable management of tailing deposits. Indeed, MICP have been reported as a technology suitable for removal and/or immobilization of heavy metals, creation of impermeable barriers, prevention of soil liquefaction and control of windblown dust emissions. However, several challenges still need to be addressed to enable relible full-scale implementation, requiring research in the near future. These are consideration of the particular chemical composition of tailings, reduction of urea requirements, determination of optimal reagents dosage, evaluation of the long term stability of the treatment and calculation of costs associated to ecah particular application.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0892-6875 ISBN Medium
Area Expedition Conference
Notes WOS:000903969400003 Approved
Call Number UAI @ alexi.delcanto @ Serial 1714
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