Quantitative image analysis as a diagnostic tool for identifying structural changes during a revival process of anaerobic granular sludge
Autor(a) principal: | |
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Data de Publicação: | 2007 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | https://hdl.handle.net/1822/6308 |
Resumo: | Due to unspecified operational problems, the specific acetoclastic activity (SAA) of the anaerobic granular sludge present in an industrial UASB reactor was considerably damaged (from 250 to less than 10mL CH4@STP/gVSS.d), significantly reducing the biogas production of that industrial unit. The hydrogenotrophic methanogenic activity exhibited a value of 600mL CH4@STP/gVSS.d, the settling velocity was 31.479.8 m/h, the average equivalent diameter was 0.9270.43mm, and about 70% of the VSS were structured in aggregates larger than 1mm. In order to study the recovery of the SAA, this sludge was collected and inoculated in a lab-scale expanded granular sludge blanket (EGSB) reactor. Ethanol was fed as the sole carbon source during a trial period of 106 days. Process monitoring included COD removal efficiency, methane production, and periodic determination of the specific methanogenic activity in the presence of acetate, propionate, butyrate, ethanol and H2/CO2. Quantitative image analysis allowed for information to be obtained on granular fragmentation/erosion and filaments release. During the first operational period, biogas production was mainly due to the hydrogenotrophic activity. However, after 40 days, the SAA steadily increased achieving a maximum value of 183713mL CH4@STP/gVSS.d. The onset of SAA recovery, granules breakdown and filaments release to the bulk occurred simultaneously. Further increase in SAA was accompanied by granular growth. In the last 25 days of operation, the size distribution was stable with more than 80% of projected area of aggregates corresponding to granules larger than 1mm (equivalent diameter). Confocal images from FISH hybridized sections of the granules showed that after SAA recovery, the granules developed an organized structure where an acidogenic/acetogenic external layer was apparent. Granular fragmentation and increase of filaments in the bulk, simultaneously with the increase in the acetoclastic activity are described for the first time and might represent a structural response of granular sludge to promote the optimal substrate uptake at minimal diffusion limitations. |
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Quantitative image analysis as a diagnostic tool for identifying structural changes during a revival process of anaerobic granular sludgeGranular sludgeQuantitative image analysisSpecific methanogenic activityStructural changes of anaerobic granular sludgeScience & TechnologyDue to unspecified operational problems, the specific acetoclastic activity (SAA) of the anaerobic granular sludge present in an industrial UASB reactor was considerably damaged (from 250 to less than 10mL CH4@STP/gVSS.d), significantly reducing the biogas production of that industrial unit. The hydrogenotrophic methanogenic activity exhibited a value of 600mL CH4@STP/gVSS.d, the settling velocity was 31.479.8 m/h, the average equivalent diameter was 0.9270.43mm, and about 70% of the VSS were structured in aggregates larger than 1mm. In order to study the recovery of the SAA, this sludge was collected and inoculated in a lab-scale expanded granular sludge blanket (EGSB) reactor. Ethanol was fed as the sole carbon source during a trial period of 106 days. Process monitoring included COD removal efficiency, methane production, and periodic determination of the specific methanogenic activity in the presence of acetate, propionate, butyrate, ethanol and H2/CO2. Quantitative image analysis allowed for information to be obtained on granular fragmentation/erosion and filaments release. During the first operational period, biogas production was mainly due to the hydrogenotrophic activity. However, after 40 days, the SAA steadily increased achieving a maximum value of 183713mL CH4@STP/gVSS.d. The onset of SAA recovery, granules breakdown and filaments release to the bulk occurred simultaneously. Further increase in SAA was accompanied by granular growth. In the last 25 days of operation, the size distribution was stable with more than 80% of projected area of aggregates corresponding to granules larger than 1mm (equivalent diameter). Confocal images from FISH hybridized sections of the granules showed that after SAA recovery, the granules developed an organized structure where an acidogenic/acetogenic external layer was apparent. Granular fragmentation and increase of filaments in the bulk, simultaneously with the increase in the acetoclastic activity are described for the first time and might represent a structural response of granular sludge to promote the optimal substrate uptake at minimal diffusion limitations.We gratefully acknowledge the financial support to P. Araya-Kroff, J.C. Costa and Ângela Abreu through the Grants SFRH/BD/3187/2000, SFRH/BD/13317/2003, and the Project POCTI/BIO/37934/2001, respectively, from the Fundação para a Ciência e a Tecnologia (Portugal). Special thanks to Dr. Damien Batstone (DTU, Lyngby, Denmark) for help with confocal microscopy and to Dr. Anthony Danko for English revision.Elsevier Ltd.Universidade do MinhoAbreu, A. A.Costa, J. C.Araya-Kroff, P.Ferreira, Eugénio C.Alves, M. M.2007-042007-04-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttps://hdl.handle.net/1822/6308engABREU, A., COSTA, J., ARAYAKROFF, P., FERREIRA, E., & ALVES, M. (2007, April). Quantitative image analysis as a diagnostic tool for identifying structural changes during a revival process of anaerobic granular sludge. Water Research. Elsevier BV. http://doi.org/10.1016/j.watres.2007.01.0170043-135410.1016/j.watres.2007.01.01717316742https://www.sciencedirect.com/science/article/pii/S0043135407000383info:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-07-21T12:10:03Zoai:repositorium.sdum.uminho.pt:1822/6308Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T19:01:36.032365Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Quantitative image analysis as a diagnostic tool for identifying structural changes during a revival process of anaerobic granular sludge |
title |
Quantitative image analysis as a diagnostic tool for identifying structural changes during a revival process of anaerobic granular sludge |
spellingShingle |
Quantitative image analysis as a diagnostic tool for identifying structural changes during a revival process of anaerobic granular sludge Abreu, A. A. Granular sludge Quantitative image analysis Specific methanogenic activity Structural changes of anaerobic granular sludge Science & Technology |
title_short |
Quantitative image analysis as a diagnostic tool for identifying structural changes during a revival process of anaerobic granular sludge |
title_full |
Quantitative image analysis as a diagnostic tool for identifying structural changes during a revival process of anaerobic granular sludge |
title_fullStr |
Quantitative image analysis as a diagnostic tool for identifying structural changes during a revival process of anaerobic granular sludge |
title_full_unstemmed |
Quantitative image analysis as a diagnostic tool for identifying structural changes during a revival process of anaerobic granular sludge |
title_sort |
Quantitative image analysis as a diagnostic tool for identifying structural changes during a revival process of anaerobic granular sludge |
author |
Abreu, A. A. |
author_facet |
Abreu, A. A. Costa, J. C. Araya-Kroff, P. Ferreira, Eugénio C. Alves, M. M. |
author_role |
author |
author2 |
Costa, J. C. Araya-Kroff, P. Ferreira, Eugénio C. Alves, M. M. |
author2_role |
author author author author |
dc.contributor.none.fl_str_mv |
Universidade do Minho |
dc.contributor.author.fl_str_mv |
Abreu, A. A. Costa, J. C. Araya-Kroff, P. Ferreira, Eugénio C. Alves, M. M. |
dc.subject.por.fl_str_mv |
Granular sludge Quantitative image analysis Specific methanogenic activity Structural changes of anaerobic granular sludge Science & Technology |
topic |
Granular sludge Quantitative image analysis Specific methanogenic activity Structural changes of anaerobic granular sludge Science & Technology |
description |
Due to unspecified operational problems, the specific acetoclastic activity (SAA) of the anaerobic granular sludge present in an industrial UASB reactor was considerably damaged (from 250 to less than 10mL CH4@STP/gVSS.d), significantly reducing the biogas production of that industrial unit. The hydrogenotrophic methanogenic activity exhibited a value of 600mL CH4@STP/gVSS.d, the settling velocity was 31.479.8 m/h, the average equivalent diameter was 0.9270.43mm, and about 70% of the VSS were structured in aggregates larger than 1mm. In order to study the recovery of the SAA, this sludge was collected and inoculated in a lab-scale expanded granular sludge blanket (EGSB) reactor. Ethanol was fed as the sole carbon source during a trial period of 106 days. Process monitoring included COD removal efficiency, methane production, and periodic determination of the specific methanogenic activity in the presence of acetate, propionate, butyrate, ethanol and H2/CO2. Quantitative image analysis allowed for information to be obtained on granular fragmentation/erosion and filaments release. During the first operational period, biogas production was mainly due to the hydrogenotrophic activity. However, after 40 days, the SAA steadily increased achieving a maximum value of 183713mL CH4@STP/gVSS.d. The onset of SAA recovery, granules breakdown and filaments release to the bulk occurred simultaneously. Further increase in SAA was accompanied by granular growth. In the last 25 days of operation, the size distribution was stable with more than 80% of projected area of aggregates corresponding to granules larger than 1mm (equivalent diameter). Confocal images from FISH hybridized sections of the granules showed that after SAA recovery, the granules developed an organized structure where an acidogenic/acetogenic external layer was apparent. Granular fragmentation and increase of filaments in the bulk, simultaneously with the increase in the acetoclastic activity are described for the first time and might represent a structural response of granular sludge to promote the optimal substrate uptake at minimal diffusion limitations. |
publishDate |
2007 |
dc.date.none.fl_str_mv |
2007-04 2007-04-01T00:00:00Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
https://hdl.handle.net/1822/6308 |
url |
https://hdl.handle.net/1822/6308 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
ABREU, A., COSTA, J., ARAYAKROFF, P., FERREIRA, E., & ALVES, M. (2007, April). Quantitative image analysis as a diagnostic tool for identifying structural changes during a revival process of anaerobic granular sludge. Water Research. Elsevier BV. http://doi.org/10.1016/j.watres.2007.01.017 0043-1354 10.1016/j.watres.2007.01.017 17316742 https://www.sciencedirect.com/science/article/pii/S0043135407000383 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Elsevier Ltd. |
publisher.none.fl_str_mv |
Elsevier Ltd. |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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RCAAP |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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1799132415495503872 |