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Caparroz M, Guzmán JL, Berenguel M, Acién FG. A novel data-driven model for prediction and adaptive control of pH in raceway reactor for microalgae cultivation. N Biotechnol 2024; 82:1-13. [PMID: 38615946 DOI: 10.1016/j.nbt.2024.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 04/05/2024] [Accepted: 04/11/2024] [Indexed: 04/16/2024]
Abstract
This work proposes a new data-driven model to estimate and predict pH dynamics in freshwater raceway photobioreactors. The resulting model is based purely on data measured from the reactor and divides the pH dynamics into two different behaviors. One behavior is described by the variation of pH due to the photosynthesis phenomena made by microalgae; and the other comes from the effect of CO2 injections into the medium for control purposes. Moreover, it was observed that the model parameters vary throughout the day depending on the weather conditions and reactor status. Thus, a decision tree algorithm is also developed to capture the parameter variation based on measured variables of the system, such as solar radiation, medium temperature, and medium level. The proposed model has been validated for a data set of more than 100 days during 10 months in a semi-industrial raceway reactor, covering a wide range of weather and system scenarios. Additionally, the proposed model was used to design an adaptive control algorithm which was also experimentally tested and compared with a classical fixed parameter control approach.
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Affiliation(s)
- M Caparroz
- University of Almería, Department of Informatics, ceiA3, CIESOL, Ctra. Sacramento, Almería 04120, Spain
| | - J L Guzmán
- University of Almería, Department of Informatics, ceiA3, CIESOL, Ctra. Sacramento, Almería 04120, Spain.
| | - M Berenguel
- University of Almería, Department of Informatics, ceiA3, CIESOL, Ctra. Sacramento, Almería 04120, Spain
| | - F G Acién
- University of Almería, Department of Chemical Engineering, ceiA3, CIESOL, Ctra. Sacramento, Almería 04120, Spain
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2
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Nordio R, Viviano E, Sánchez-Zurano A, Hernández JG, Rodríguez-Miranda E, Guzmán JL, Acién G. Influence of pH and dissolved oxygen control strategies on the performance of pilot-scale microalgae raceways using fertilizer or wastewater as the nutrient source. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 345:118899. [PMID: 37673007 DOI: 10.1016/j.jenvman.2023.118899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 08/14/2023] [Accepted: 08/27/2023] [Indexed: 09/08/2023]
Abstract
Dissolved oxygen concentration and pH are controllable and cost-effective variables that determine the success of microalgae-related processes. The present study compares different control strategies for pH and dissolved oxygen in pilot-scale microalgae production systems. Two 80 m2 raceway reactors were used, one operated with freshwater plus fertilizer and the other with wastewater as the nutrient source. Both were in semi-continuous mode at a fixed dilution rate of 0.2 day-1. A comparison between the classical On-Off and more advanced pH control strategies, such as PI and Event-based control, was performed, focusing on biomass productivity and the influence of all the process parameters on microalgae growth; "No control" of pH was also assayed. The results show that Event-based control was the best algorithm when using freshwater plus fertilizer. In contrast, no significant differences were observed using the different control strategies when wastewater was the nutrient source. These experiments were performed through selective control strategy, prioritizing pH over dissolved oxygen; however, it was demonstrated that they did not allow to achieve satisfactory dissolved oxygen removal results, especially for the fertilizer system. After modifying the gas diffuser configuration and improving the mass transfer, independent on-off strategies have been developed, permitting effective control of both variables and increasing productivity by up to 20% in both systems. Concluding, a detailed analysis of the energy demand for each strategy implemented in terms of gas consumption and gas flow to biomass ratio is provided.
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Affiliation(s)
- Rebecca Nordio
- Department of Chemical Engineering, Universidad de Almería, E04120, Almería, Spain; CIESOL Solar Energy Research Centre, Joint Centre University of Almería-CIEMAT, 04120, Almería, Spain.
| | | | - Ana Sánchez-Zurano
- Department of Chemical Engineering, Universidad de Almería, E04120, Almería, Spain; CIESOL Solar Energy Research Centre, Joint Centre University of Almería-CIEMAT, 04120, Almería, Spain
| | | | | | - José Luis Guzmán
- Department of Informatics, Universidad de Almería, E04120, Almería, Spain
| | - Gabriel Acién
- Department of Chemical Engineering, Universidad de Almería, E04120, Almería, Spain; CIESOL Solar Energy Research Centre, Joint Centre University of Almería-CIEMAT, 04120, Almería, Spain
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3
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Nordio R, Delgado FJ, Sánchez-Zurano A, Hernandez JG, Rodríguez-Miranda E, Guzmán JL, Lafarga T, Acién G. Long-term assessment of the nutrient recovery capacity and biomass productivity of Scenedesmus almeriensis in raceway reactors using unprocessed urban wastewater. BIORESOURCE TECHNOLOGY 2023; 369:128374. [PMID: 36423751 DOI: 10.1016/j.biortech.2022.128374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/15/2022] [Accepted: 11/17/2022] [Indexed: 06/16/2023]
Abstract
The present work aims to assess the treatment of unprocessed urban wastewater using the microalga Scenedesmus almeriensis. Two 12 m3 raceway reactors, one supplemented by wastewater and the second by chemical fertilizer, operating outdoors in a semi-continuous mode, were used for eight months. Results suggested that S. almeriensis can be produced in wastewater without affecting the photosynthetic apparatus reaching a productivity of 13 g·m-2·day-1 on average in both the systems. Furthermore, the nutrient content in terms of nitrogen, phosphorous and chemical oxygen demand of the wastewater was reduced under the European limitations during most of the period, with an average removal rate of 2.2, 0.2 and 3.0 g·m-2·day-1 respectively. Therefore, raceways demonstrated a high potential for microalgal production and successful biotreatment, proving robust and reliable. Finally, the effect of environmental conditions on biomass productivity of the clean system was evaluated in a model with high accuracy (R2 = 0.9, p = 0.0002).
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Affiliation(s)
- Rebecca Nordio
- Department of Chemical Engineering, Universidad de Almería, E04120 Almería, Spain; CIESOL Solar Energy Research Centre, Joint Centre University of Almería-CIEMAT, 04120 Almería, Spain.
| | | | - Ana Sánchez-Zurano
- Department of Chemical Engineering, Universidad de Almería, E04120 Almería, Spain; CIESOL Solar Energy Research Centre, Joint Centre University of Almería-CIEMAT, 04120 Almería, Spain
| | | | | | - José Luis Guzmán
- CIESOL Solar Energy Research Centre, Joint Centre University of Almería-CIEMAT, 04120 Almería, Spain; Department of Informatics, Universidad de Almería, ceiA3, E04120 Almería, Spain
| | - Tomás Lafarga
- Department of Chemical Engineering, Universidad de Almería, E04120 Almería, Spain; CIESOL Solar Energy Research Centre, Joint Centre University of Almería-CIEMAT, 04120 Almería, Spain
| | - Gabriel Acién
- Department of Chemical Engineering, Universidad de Almería, E04120 Almería, Spain; CIESOL Solar Energy Research Centre, Joint Centre University of Almería-CIEMAT, 04120 Almería, Spain
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4
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Inostroza C, El Bahraoui N, Rivera-Tinoco R, Acién FG. Uses of electro-coagulation-flocculation (ECF) for the pre-concentration of microalgae biomass. Process Biochem 2022. [DOI: 10.1016/j.procbio.2022.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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5
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Microalgae Cultivation on Nutrient Rich Digestate: The Importance of Strain and Digestate Tailoring under PH Control. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12115429] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The bioremediation of digestate using microalgae presents a solution to the current eutrophication issue in Northwest Europe, where the use of digestate as soil fertiliser is limited, thus resulting in an excess of digestate. Ammonium is the main nutrient of interest in digestate for microalgal cultivation, and improving its availability and consequent uptake is crucial for optimal bioremediation. This work aimed to determine the influence of pH on ammonium availability in cultures of two green microalgae, additionally screened for their growth performances on three digestates produced from different feedstocks, demonstrating the importance of tailoring a microalgal strain and digestate for bioremediation purposes. Results showed that an acidic pH of 6–6.5 resulted in a better ammonium availability in the digestate media, translated into better growth yields for both S. obliquus (GR: 0.099 ± 0.001 day−1; DW: 0.23 ± 0.02 g L−1) and C. vulgaris (GR: 0.09 ± 0.001 day−1; DW: 0.49 ± 0.012 g L−1). This result was especially true when considering larger-scale applications where ammonium loss via evaporation should be avoided. The results also demonstrated that digestates from different feedstocks resulted in different growth yields and biomass composition, especially fatty acids, for which, a digestate produced from pig manure resulted in acid contents of 6.94 ± 0.033% DW and 4.91 ± 0.3% DW in S. obliquus and C. vulgaris, respectively. Finally, this work demonstrated that the acclimation of microalgae to novel nutrient sources should be carefully considered, as it could convey significant advantages in terms of biomass composition, especially fatty acids and carbohydrate, for which, this study also demonstrated the importance of harvesting time.
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6
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Rodríguez-Miranda E, Sánchez-Zurano A, Guzmán JL, Acién G, Visioli A. A seasonal simulation approach for culture depth influence on the temperature for different characterized microalgae strains. Biotechnol J 2022; 17:e2100489. [PMID: 35567392 DOI: 10.1002/biot.202100489] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 04/29/2022] [Accepted: 05/07/2022] [Indexed: 11/07/2022]
Abstract
Irradiance and temperature are among the most important variables that affect microalgae growth, being both difficult to control in outdoor raceway reactors utilized for large-scale production of microalgae biomass. They are mainly a function of the location of the reactors, thus, producing certain strains of microalgae in inappropriate places conduces to the failure of the systems. To be able to determine important parameters of any microalgae strains on the performance of the culture, such as the influence of irradiance and temperature, is a powerful tool in decision-making processes. In addition, whatever the strain and location, operation strategies must be defined for each specific case, such as the imposed dilution rate and culture depth, both influencing the light availability and temperature of the culture as major variables determining the biomass productivity. In this paper, a simulation-based methodology is proposed to establish the influence of season and culture depth on the 1-year age irradiance and temperature of the culture, and thus on the biomass productivity of different microalgae strains. Up to five of the most frequently produced strains, such as Spirulina platensis, Chlorella vulgaris, Nannochloropsis gaditana, Isochrysis galbana and Scenedesmus almeriensis have been considered. The challenge is to develop an easy-to-manage decision-making tool for the optimal design and operation of large-scale microalgae facilities. Especially, dates for microalgae production and culture depth at which the reactors must be operated will be provided, being valid for any microalgae strain. The proposed methodology will largely contribute to the risk of investment in this field, then to enlarge the relevance of the microalgae production industry. This article is protected by copyright. All rights reserved.
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Affiliation(s)
| | - Ana Sánchez-Zurano
- Departamento de Ingeniería Química, CIESOL ceiA3, Universidad de Almería, Almería, Spain
| | - José Luis Guzmán
- Departamento de Informática, CIESOL ceiA3, Universidad de Almería, Almería, Spain
| | - Gabriel Acién
- Departamento de Ingeniería Química, CIESOL ceiA3, Universidad de Almería, Almería, Spain
| | - Antonio Visioli
- Department of Mechanical and Industrial Engineering, University of Brescia, Brescia, Italy
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7
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Outflow from a Biogas Plant as a Medium for Microalgae Biomass Cultivation—Pilot Scale Study and Technical Concept of a Large-Scale Installation. ENERGIES 2022. [DOI: 10.3390/en15082912] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Microalgae-based technologies have huge potential for application in the environment sector and the bio-energy industry. However, their cost-efficiency has to be improved by drawing on design and operation data for large-scale installations. This paper presents a technical concept of an installation for large-scale microalgae culture on digestate liquor, and the results of a pilot-scale study to test its performance. The quality of non-treated digestate has been shown to be insufficient for direct use as a growth medium due to excess suspended solids, turbidity, and organic matter content, which need to be reduced. To that end, this paper proposes a system based on mechanical separation, flotation, and pre-treatment on a biofilter. The culture medium fed into photobioreactors had the following parameters after the processing: COD—340 mgO2/dm3, BOD5—100 mgO2/dm3, TN—900 mg/dm3, and TP—70 mg/dm3. The installation can produce approx. 720 kgVS/day of microalgal biomass. A membrane unit and a thickening centrifuge (thickener) were incorporated into the design to separate and dehydrate the microalgal biomass, respectively. The total energy consumption approximated 1870 kWh/day.
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8
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Barceló-Villalobos M, Hoyo Á, Rodríguez-Miranda E, Guzmán JL, Acién FG. A new control strategy to improve the mass transfer capacity and reduce air injection costs in raceway reactors. N Biotechnol 2022; 70:49-56. [DOI: 10.1016/j.nbt.2022.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 04/18/2022] [Accepted: 04/19/2022] [Indexed: 11/28/2022]
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9
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Aparicio S, Robles Á, Ferrer J, Seco A, Borrás Falomir L. Assessing and modeling nitrite inhibition in microalgae-bacteria consortia for wastewater treatment by means of photo-respirometric and chlorophyll fluorescence techniques. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 808:152128. [PMID: 34863736 DOI: 10.1016/j.scitotenv.2021.152128] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/23/2021] [Accepted: 11/28/2021] [Indexed: 06/13/2023]
Abstract
Total nitrite (TNO2 = HNO2 + NO-2) accumulation due to the activity of ammonia-oxidizing bacteria (AOB) was monitored in microalgae-bacteria consortia, and the inhibitory effect of nitrite/free nitrous acid (NO2-N/FNA) on microalgae photosynthesis and inhibition mechanism was studied. A culture of Scenedesmus was used to run two sets of batch reactors at different pH and TNO2 concentrations to evaluate the toxic potential of NO2-N and FNA. Photo-respirometric tests showed that NO2-N accumulation has a negative impact on net oxygen production rate (OPRNET). Chlorophyll a fluorescence analysis was used to examine the biochemical effects of NO2-N stress and the mechanism of NO2-N inhibition. The electron transport rate (ETR), non-photochemical quenching (NPQ), and JIP-test revealed that the electron transport chain between Photosystems II and I (PS II and PS I) was hindered at NO2-N concentrations above 25 g N m-3. Electron acceptor QA was not able to reoxidize and could not transfer electrons to the next electron acceptor, QB, accumulating P680+ (excited PS II reaction center) and limiting oxygen production. A semi-continuous reactor containing a Scenedesmus culture was monitored by photo-respirometry tests and Chlorophyll a fluorescence to calibrate NO2-N inhibition (5-35 g N m-3). Non-competitive inhibition and Hill-type models were compared to select the best-fitting inhibition equations. Inhibition was correctly modeled by the Hill-type model and a half inhibition constant (KI) for OPRNET, NPQ, maximum photosynthetic rate (ETRMAX) and the performance index PIABS was 23.7 ± 1.2, 26.36 ± 1.10, 39 ± 2 and 26.5 ± 0.4, respectively.
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Affiliation(s)
- Stéphanie Aparicio
- CALAGUA - Unidad Mixta UV-UPV, Departament d'Enginyeria Química, Universitat de València, Avinguda de la Universitat s/n, 46100 Burjassot, València, Spain.
| | - Ángel Robles
- CALAGUA - Unidad Mixta UV-UPV, Departament d'Enginyeria Química, Universitat de València, Avinguda de la Universitat s/n, 46100 Burjassot, València, Spain
| | - José Ferrer
- CALAGUA - Unidad Mixta UV-UPV, Institut Universitari d'Investigació d'Enginyeria de l'Aigua i Medi Ambient - IIAMA, Universitat Politècnica de València, Camí de Vera s/n, 46022, València, Spain
| | - Aurora Seco
- CALAGUA - Unidad Mixta UV-UPV, Departament d'Enginyeria Química, Universitat de València, Avinguda de la Universitat s/n, 46100 Burjassot, València, Spain
| | - Luis Borrás Falomir
- CALAGUA - Unidad Mixta UV-UPV, Departament d'Enginyeria Química, Universitat de València, Avinguda de la Universitat s/n, 46100 Burjassot, València, Spain
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10
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A computer-based tool to simulate raceway photobioreactors for design, operation and control purposes. Comput Chem Eng 2022. [DOI: 10.1016/j.compchemeng.2021.107572] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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11
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Collao J, Morales-Amaral MDM, Acién-Fernández FG, Bolado-Rodríguez S, Fernandez-Gonzalez N. Effect of operational parameters, environmental conditions, and biotic interactions on bacterial communities present in urban wastewater treatment photobioreactors. CHEMOSPHERE 2021; 284:131271. [PMID: 34182290 DOI: 10.1016/j.chemosphere.2021.131271] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 04/30/2021] [Accepted: 06/15/2021] [Indexed: 06/13/2023]
Abstract
The effects of water depth, operational and environmental conditions on bacterial communities were analyzed in microalgal-bacterial outdoor photobioreactors treating urban wastewaters from March to August 2014. Three raceway photobioreactors inoculated with Scenedesmus sp. and with different water depths (20, 12, and 5 cm) were used at different dilution rates (0.15, 0.3, 0.4, and 0.5 d-1). A thin-layer reactor with 2 cm water depth and operated at 0.3 d-1 was used as a control. The results showed that biomass productivity increased as water depth decreased. The highest biomass productivity was 0.196 gL-1d-1, 0.245 gL-1d-1, and 0.457 gL-1d-1 for 20, 12, and 5 cm depth raceway photobioreactors, respectively. These values were lower than the maximum productivity registered in the control reactor (1.59 gL-1d-1). Bacterial communities, analyzed by high-throughput 16S rRNA sequencing, were not affected by water depth. A decrease in community evenness was related to a decrease in nutrient removal. Hetetrotrophs and phototrophs, mainly from the family Rhodobacteraceae, dominated bacterial diversity. The community changed due to increasing temperatures, irradiance, and organic carbon, ammonia, and phosphate contents in the photobioreactor-influent as well as, microalgae inhibition and higher organic carbon in the effluent. The photobioreactors shared a core-biome that contained five clusters of co-occurring microorganisms. The bacteria from the different clusters were taxonomically and ecologically different but functionally redundant. Overall, the drivers of the community changes could be related to abiotic variables and complex biological interactions, likely mediated by microalgae excretion of organic substances and the microorganisms' competence for substrates.
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Affiliation(s)
- Javiera Collao
- Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n, 47011, Valladolid, Spain; Institute of Sustainable Processes (ISP), Dr. Mergelina s/n, 47011, Valladolid, Spain
| | | | | | - Silvia Bolado-Rodríguez
- Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n, 47011, Valladolid, Spain; Institute of Sustainable Processes (ISP), Dr. Mergelina s/n, 47011, Valladolid, Spain
| | - Nuria Fernandez-Gonzalez
- Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n, 47011, Valladolid, Spain; Institute of Sustainable Processes (ISP), Dr. Mergelina s/n, 47011, Valladolid, Spain.
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12
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Masojídek J, Ranglová K, Rearte TA, Celis Plá PS, Torzillo G, Benavides AMS, Neori A, Gómez C, Álvarez-Gómez F, Lukeš M, Caporgno MP, Abdala R, Miazek K, Massocato TF, da Silva JC, Atzmüller R, Al Mahrouqui H, Estrella FS, Figueroa FL. Changes in photosynthesis, growth and biomass composition in outdoor Chlorella g120 culture during the metabolic shift from heterotrophic to phototrophic cultivation regime. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102303] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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13
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Improvement of real-scale raceway bioreactors for microalgae production using Computational Fluid Dynamics (CFD). ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102207] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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14
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Rearte TA, Celis-Plá PS, Neori A, Masojídek J, Torzillo G, Gómez-Serrano C, Silva Benavides AM, Álvarez-Gómez F, Abdala-Díaz R, Ranglová K, Caporgno M, Massocato TF, da Silva JC, Al Mahrouqui H, Atzmüller R, Figueroa FL. Photosynthetic performance of Chlorella vulgaris R117 mass culture is moderated by diurnal oxygen gradients in an outdoor thin layer cascade. ALGAL RES 2021. [DOI: 10.1016/j.algal.2020.102176] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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15
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Bani A, Fernandez FGA, D'Imporzano G, Parati K, Adani F. Influence of photobioreactor set-up on the survival of microalgae inoculum. BIORESOURCE TECHNOLOGY 2021; 320:124408. [PMID: 33246238 DOI: 10.1016/j.biortech.2020.124408] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/05/2020] [Accepted: 11/07/2020] [Indexed: 06/11/2023]
Abstract
Cultivation of specific microalgae is still difficult in an industrial setup as contamination and balancing the economic cost are not always possible. Understanding the ecology of cultivation of microalgae is therefore necessary to implement stable production. The aim of the study was to understand how different types of photobioreactors and types of culture medium influenced the survival of a specific microalgae inoculum, S. almeriensis. The bacterial and microalgae community were studied using Illumina sequencing. Only the closed configuration was able to maintain the inoculated species while all the other systems developed a different eukaryotic community due to contamination and the higher fitness of contaminants. Photobioreactor configuration was more important than medium in shaping the eukaryotes community, while the bacterial community was influenced strongly by both. Results showed that even a well-adapted strain is maintained only in the closed reactor while the open reactors are colonized by a multispecies consortium.
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Affiliation(s)
- Alessia Bani
- Gruppo Ricicla labs., Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia (DiSAA), Università degli studi di Milano, Via Celoria 2, 20133, Italy; Istituto Sperimentale Lazzaro Spallanzani, loc La Quercia 2602 Rivolta d'Adda, CR, Italy
| | | | - Giuliana D'Imporzano
- Gruppo Ricicla labs., Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia (DiSAA), Università degli studi di Milano, Via Celoria 2, 20133, Italy
| | - Katia Parati
- Istituto Sperimentale Lazzaro Spallanzani, loc La Quercia 2602 Rivolta d'Adda, CR, Italy.
| | - Fabrizio Adani
- Gruppo Ricicla labs., Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia (DiSAA), Università degli studi di Milano, Via Celoria 2, 20133, Italy
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16
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Rodríguez-Miranda E, Guzmán JL, Acién FG, Berenguel M, Visioli A. Indirect regulation of temperature in raceway reactors by optimal management of culture depth. Biotechnol Bioeng 2020; 118:1186-1198. [PMID: 33270219 DOI: 10.1002/bit.27642] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 11/17/2020] [Accepted: 11/28/2020] [Indexed: 01/16/2023]
Abstract
Temperature and irradiance are the two most relevant factors determining the performance of microalgae cultures in open raceway reactors. Moreover, inadequate temperature strongly reduces the biomass productivity in these systems even if enough sunlight is available. Controlling the temperature in large open raceway reactors is considered unaffordable because of the large amount of energy required. This study presents an indirect method for temperature regulation in microalgae raceway reactors by optimizing the culture depth. First, the effect of the culture depth on the raceway temperature is analyzed for different seasons of the year. Afterward, a simulation study is presented where the proposed control approach is compared to the normal operation mode with constant volume in the reactor. This study is also extended to industrial scale. Relevant improvements on the temperature factor and biomass production are presented. The developed knowledge allows the improvement of the performance in open raceway reactors up to 12% without involving additional energy and costs, being a suitable solution for large industrial reactors that until now have no options for controlling the temperature.
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Affiliation(s)
- E Rodríguez-Miranda
- Department of Mechanical and Industrial Engineering, University of Brescia, Brescia, Italy
| | - J L Guzmán
- Departamento de Informática, Universidad de Almería, Almería, Spain
| | - F G Acién
- Departamento de Ingenierı́a, Universidad de Almería, Almería, Spain
| | - M Berenguel
- Departamento de Informática, Universidad de Almería, Almería, Spain
| | - A Visioli
- Department of Mechanical and Industrial Engineering, University of Brescia, Brescia, Italy
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17
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Sánchez Zurano A, Gómez Serrano C, Acién-Fernández FG, Fernández-Sevilla JM, Molina-Grima E. Modeling of photosynthesis and respiration rate for microalgae-bacteria consortia. Biotechnol Bioeng 2020; 118:952-962. [PMID: 33179264 DOI: 10.1002/bit.27625] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 10/16/2020] [Accepted: 11/05/2020] [Indexed: 02/06/2023]
Abstract
In this article, the influence of culture conditions (irradiance, temperature, pH, and dissolved oxygen) on the photosynthesis and the respiration rates of microalgae-bacteria consortia in wastewater treatment was analyzed. Specifically, some short photo-respirometric experiments, simulating outdoor raceway reactors, were performed to evaluate the response of microalgae, heterotrophic bacteria, and nitrifying bacteria to variations in environmental parameters. Results demonstrate that irradiance is the most dominant variable to determine microalgae photosynthesis rates. However, reduction in microalgae activity was not observed at higher irradiance, ruling out the existence of photoinhibition phenomena. Related to heterotrophic and nitrifying bacteria, their activities were strongly affected by the influence of temperature and pH. Moreover, the effect of dissolved oxygen concentrations on microalgae, and bacteria activities was studied, displaying a reduced photosynthetic rate at dissolved oxygen concentrations above 20 mg/L. Data have been used to develop an integrated model for each population (microalgae, heterotrophic bacteria, and nitrifying bacteria) based on considering the simultaneous influence of irradiance, temperature, pH, and dissolved oxygen. The models fit the experimental results in the range of culture conditions tested, and they were validated using data obtained by the simultaneous modifications of the variables. These individual models serve as a basis for developing a global biologic microalgae-bacteria model for wastewater treatment to improve the optimal design and management of microalgae-based processes, especially outdoors, where the cultures are subject to variable daily culture conditions.
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Affiliation(s)
- Ana Sánchez Zurano
- Department of Chemical Engineering, University of Almeria, Almería, Spain
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Rodríguez-Miranda E, Acién FG, Guzmán JL, Berenguel M, Visioli A. A new model to analyze the temperature effect on the microalgae performance at large scale raceway reactors. Biotechnol Bioeng 2020; 118:877-889. [PMID: 33140848 DOI: 10.1002/bit.27617] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 10/18/2020] [Accepted: 10/22/2020] [Indexed: 11/11/2022]
Abstract
In this study a simplified temperature model for raceway reactors is developed, allowing to determine the temperature of the microalgae culture as a function of reactor design and environmental conditions. The model considers the major phenomena taking place in raceway reactors, especially heat absorption by radiation and heat losses by evaporation among others. The characteristic parameters of the model have been calibrated using genetic algorithms, next being validated with a long set of more than 50 days covering different weather conditions. It is worth to highlight the use of the developed model as a tool to analyze the influence of the temperature on the performance of microalgae cultures at large scale. As example, the annual variation of the performance of up to five different microalgae strains has been determined by computing the temperature index, thus the normalized value of performance of whatever microalgae at the real temperature with respect to that achievable at optimal temperature can be established. Results confirm that only strains tolerant to wide ranges of temperature can be efficiently produced all the year around in large scale outdoor raceway reactors without additional temperature control systems.
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Affiliation(s)
| | | | - Jose L Guzmán
- Dep. de Informática, Universidad de Almería, CIESOL ceiA3, Almería, Spain
| | - Manuel Berenguel
- Dep. de Informática, Universidad de Almería, CIESOL ceiA3, Almería, Spain
| | - Antonio Visioli
- Department of Mechanical and Industrial Engineering, University of Brescia, Brescia, Italy
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Morillas-España A, Lafarga T, Gómez-Serrano C, Acién-Fernández FG, González-López CV. Year-long production of Scenedesmus almeriensis in pilot-scale raceway and thin-layer cascade photobioreactors. ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.102069] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Rossi S, Casagli F, Mantovani M, Mezzanotte V, Ficara E. Selection of photosynthesis and respiration models to assess the effect of environmental conditions on mixed microalgae consortia grown on wastewater. BIORESOURCE TECHNOLOGY 2020; 305:122995. [PMID: 32105843 DOI: 10.1016/j.biortech.2020.122995] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 02/06/2020] [Accepted: 02/08/2020] [Indexed: 06/10/2023]
Abstract
This study aimed at evaluating the effects of different environmental conditions (irradiance, temperature, pH and dissolved oxygen) on a microalgae-bacteria consortium cultivated in a pilot-scale open pond and fed on the liquid fraction of anaerobic digestate. A standardized photo-respirometry protocol was followed to evaluate the activity of microalgae under different conditions. Two datasets (specific photosynthetic oxygen production rates and respiratory oxygen consumption rates) were obtained for each environmental parameter, throughout the entire range of conditions found in the outdoor cultivation system. Different kinetic models available in literature were fitted to experimental data and the resulting outputs were compared through model selection estimators, in order to select the most appropriate equations. The proposed set of equations constitute a modelling tool for the prediction of algal growth rates in algae-bacteria systems, as a function of environmental conditions.
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Affiliation(s)
- S Rossi
- Politecnico di Milano, Department of Civil and Environmental Engineering (DICA), P.zza L. da Vinci, 32, 20133 Milan, Italy
| | - F Casagli
- Politecnico di Milano, Department of Civil and Environmental Engineering (DICA), P.zza L. da Vinci, 32, 20133 Milan, Italy
| | - M Mantovani
- Università Degli Studi di Milano-Bicocca, Department of Earth and Environmental Sciences (DISAT), P.zza della Scienza 1, 20126 Milan, Italy
| | - V Mezzanotte
- Università Degli Studi di Milano-Bicocca, Department of Earth and Environmental Sciences (DISAT), P.zza della Scienza 1, 20126 Milan, Italy
| | - E Ficara
- Politecnico di Milano, Department of Civil and Environmental Engineering (DICA), P.zza L. da Vinci, 32, 20133 Milan, Italy.
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21
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Molino A, Mehariya S, Iovine A, Casella P, Marino T, Karatza D, Chianese S, Musmarra D. Enhancing Biomass and Lutein Production From Scenedesmus almeriensis: Effect of Carbon Dioxide Concentration and Culture Medium Reuse. FRONTIERS IN PLANT SCIENCE 2020; 11:415. [PMID: 32373140 PMCID: PMC7186383 DOI: 10.3389/fpls.2020.00415] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Accepted: 03/23/2020] [Indexed: 05/05/2023]
Abstract
The main purpose of this study is to investigate the effects of operative parameters and bioprocess strategies on the photo-autotrophic cultivation of the microalgae Scenedesmus almeriensis for lutein production. S. almeriensis was cultivated in a vertical bubble column photobioreactor (VBC-PBR) in batch mode and the bioactive compounds were extracted by accelerated solvent extraction with ethanol at 67°C and 10 MPa. The cultivation with a volume fraction of CO2 in the range 0-3.0%v/v showed that the highest biomass and lutein concentrations - 3.7 g/L and 5.71 mg/g, respectively - were measured at the highest CO2 concentration and using fresh growth medium. Recycling the cultivation medium from harvested microalgae resulted in decreased biomass and lutein content. The nutrient chemical composition analysis showed the highest consumption rates for nitrogen and phosphorus, with values higher than 80%, while sulfate and chloride were less consumed.
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Affiliation(s)
- Antonio Molino
- Department of Sustainability-CR Portici, ENEA Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Portici, Italy
| | - Sanjeet Mehariya
- Department of Sustainability-CR Portici, ENEA Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Portici, Italy
- Department of Engineering, University of Campania “Luigi Vanvitelli”, Aversa, Italy
| | - Angela Iovine
- Department of Sustainability-CR Portici, ENEA Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Portici, Italy
- Department of Engineering, University of Campania “Luigi Vanvitelli”, Aversa, Italy
| | - Patrizia Casella
- Department of Sustainability-CR Portici, ENEA Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Portici, Italy
| | - Tiziana Marino
- Department of Engineering, University of Campania “Luigi Vanvitelli”, Aversa, Italy
| | - Despina Karatza
- Department of Engineering, University of Campania “Luigi Vanvitelli”, Aversa, Italy
| | - Simeone Chianese
- Department of Engineering, University of Campania “Luigi Vanvitelli”, Aversa, Italy
- *Correspondence: Simeone Chianese,
| | - Dino Musmarra
- Department of Engineering, University of Campania “Luigi Vanvitelli”, Aversa, Italy
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22
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Bench-Scale Cultivation of Microalgae Scenedesmus almeriensis for CO2 Capture and Lutein Production. ENERGIES 2019. [DOI: 10.3390/en12142806] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this study, Scenedesmus almeriensis as green microalga was cultivated on bench-scale for carbon dioxide (CO2) capture and lutein production. The autotrophic cultivation of S. almeriensis was carried out by using a vertical bubble column photo-bioreactor (VBC-PBR) with a continuous flow of a gaseous mixture of oxygen (O2), nitrogen (N2), and CO2, the latter in content of 0.0–3.0 %v/v. The liquid phase was batch. S. almeriensis growth was optimized. In addition, lutein extraction was carried out by using accelerated solvent extraction with ethanol as Generally Recognized as Safe (GRAS) solvent at 67 °C and 10 MPa. Upon optimization of CO2 concentration, the maximum biomass productivity, equal to 129.24 mg·L−1·d−1, was achieved during the cultivation by using a content of CO2 equal to 3.0 %v/v and it allowed to obtain a lutein content of 8.54 mg·g−1, which was 5.6-fold higher in comparison to the analogous process carried out without CO2 addition. The ion chemical analysis in the growth medium showed that by gradually increasing CO2 content, the nutrient consumption during the growth phase also increased. This study may be of potential interest for lutein extraction at industrial scale, since it is focused on pigment production from a natural source with a concomitantly CO2 capture.
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