Effectiveness of chlorination and ozonation methods on pure cultures of floc-forming micro-organisms and activated sludge: a comparative study
- Autores
- Caravelli, Alejandro Horacio; Giannuzzi, Leda; Zaritzky, Noemí Elisabet
- Año de publicación
- 2006
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- Chlorination is a very useful control method of filamentous bulking in activated sludge systems; however, it favours formation; of undesirable compounds such as trihalomethanes. Other oxidants, such as ozone, could be used for bulking control. In view of the fact that chlorine and ozone are both non-selective chemical agents affecting filamentous and floc-forming micro-organisms, the determination of optimum dosage conditions becomes essential to minimise the impact produced on the activated sludge process. In this work, the effects of chlorine and ozone on the biomass concentration of activated sludge and on different parameters that characterise the microbial metabolic activity were compared. The following techniques were applied: Respirometry (oxygen uptake rate); and INT-dehydrogenase activity test carried out both by spectrophotometry (DHAa) and image analysis (DHAi). The respirometric technique and the DHAa test quantified oxidants action on the total respiratory activity of flocs; the image DHAi test was applied to evaluate the specific action of the oxidants on filamentous micro-organisms. Additionally, plate count technique, respirometry and DHAa test were correlated using chlorine and ozone experiments on pure cultures of a floc-forming micro-organism (Acinetobacter anitratus) to compare the effect of the oxidising; agents on the metabolic activity and the viability of the micro-organisms. Ozone was found to have more intense antimicrobial action. In activated sludge, ozone reduced total biomass concentration by oxidising various components and causing cell lysis. An equation was proposed to estimate biomass concentration of activated sludge as a function of time and ozone dose rate; in contrast, at the doses applied, chlorine did not reduce the concentration of activated sludge biomass. In activated sludge, adequate conditions for both oxidants were identified under which the respiratory activity of filamentous micro-organisms could be considerably inhibited, causing the lowest possible impact on whole floc metabolic activity. An initial chlorine dose of 7.9 mgCl2·gVSS-1 for a contact time of 5 min (initial pulse= 6.0 mgCl2·l-1), and a total ozone dose of 66.0 mgO3·gVSS-1 (ozone dose rate of 3.3 mgO3·gVSS-1·min-1 for a contact time of 20 min) were the most suitable conditions to control filamentous bulking.
Centro de Investigación y Desarrollo en Criotecnología de Alimentos - Materia
-
Química
Filamentous bulking
Chlorine
Ozone
INT-dehydrogenase activity
Respirometry
Image analysis
Late count - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- http://creativecommons.org/licenses/by-nc-sa/4.0/
- Repositorio
- Institución
- Universidad Nacional de La Plata
- OAI Identificador
- oai:sedici.unlp.edu.ar:10915/128235
Ver los metadatos del registro completo
id |
SEDICI_8175c8f387654ca2165059c2002f530c |
---|---|
oai_identifier_str |
oai:sedici.unlp.edu.ar:10915/128235 |
network_acronym_str |
SEDICI |
repository_id_str |
1329 |
network_name_str |
SEDICI (UNLP) |
spelling |
Effectiveness of chlorination and ozonation methods on pure cultures of floc-forming micro-organisms and activated sludge: a comparative studyCaravelli, Alejandro HoracioGiannuzzi, LedaZaritzky, Noemí ElisabetQuímicaFilamentous bulkingChlorineOzoneINT-dehydrogenase activityRespirometryImage analysisLate countChlorination is a very useful control method of filamentous bulking in activated sludge systems; however, it favours formation; of undesirable compounds such as trihalomethanes. Other oxidants, such as ozone, could be used for bulking control. In view of the fact that chlorine and ozone are both non-selective chemical agents affecting filamentous and floc-forming micro-organisms, the determination of optimum dosage conditions becomes essential to minimise the impact produced on the activated sludge process. In this work, the effects of chlorine and ozone on the biomass concentration of activated sludge and on different parameters that characterise the microbial metabolic activity were compared. The following techniques were applied: Respirometry (oxygen uptake rate); and INT-dehydrogenase activity test carried out both by spectrophotometry (DHAa) and image analysis (DHAi). The respirometric technique and the DHAa test quantified oxidants action on the total respiratory activity of flocs; the image DHAi test was applied to evaluate the specific action of the oxidants on filamentous micro-organisms. Additionally, plate count technique, respirometry and DHAa test were correlated using chlorine and ozone experiments on pure cultures of a floc-forming micro-organism (Acinetobacter anitratus) to compare the effect of the oxidising; agents on the metabolic activity and the viability of the micro-organisms. Ozone was found to have more intense antimicrobial action. In activated sludge, ozone reduced total biomass concentration by oxidising various components and causing cell lysis. An equation was proposed to estimate biomass concentration of activated sludge as a function of time and ozone dose rate; in contrast, at the doses applied, chlorine did not reduce the concentration of activated sludge biomass. In activated sludge, adequate conditions for both oxidants were identified under which the respiratory activity of filamentous micro-organisms could be considerably inhibited, causing the lowest possible impact on whole floc metabolic activity. An initial chlorine dose of 7.9 mgCl2·gVSS-1 for a contact time of 5 min (initial pulse= 6.0 mgCl2·l-1), and a total ozone dose of 66.0 mgO3·gVSS-1 (ozone dose rate of 3.3 mgO3·gVSS-1·min-1 for a contact time of 20 min) were the most suitable conditions to control filamentous bulking.Centro de Investigación y Desarrollo en Criotecnología de Alimentos2006info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdf585-595http://sedici.unlp.edu.ar/handle/10915/128235enginfo:eu-repo/semantics/altIdentifier/issn/0378-4738info:eu-repo/semantics/altIdentifier/doi/10.4314/wsa.v32i4.5283info:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by-nc-sa/4.0/Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)reponame:SEDICI (UNLP)instname:Universidad Nacional de La Platainstacron:UNLP2025-09-29T11:31:02Zoai:sedici.unlp.edu.ar:10915/128235Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:31:02.978SEDICI (UNLP) - Universidad Nacional de La Platafalse |
dc.title.none.fl_str_mv |
Effectiveness of chlorination and ozonation methods on pure cultures of floc-forming micro-organisms and activated sludge: a comparative study |
title |
Effectiveness of chlorination and ozonation methods on pure cultures of floc-forming micro-organisms and activated sludge: a comparative study |
spellingShingle |
Effectiveness of chlorination and ozonation methods on pure cultures of floc-forming micro-organisms and activated sludge: a comparative study Caravelli, Alejandro Horacio Química Filamentous bulking Chlorine Ozone INT-dehydrogenase activity Respirometry Image analysis Late count |
title_short |
Effectiveness of chlorination and ozonation methods on pure cultures of floc-forming micro-organisms and activated sludge: a comparative study |
title_full |
Effectiveness of chlorination and ozonation methods on pure cultures of floc-forming micro-organisms and activated sludge: a comparative study |
title_fullStr |
Effectiveness of chlorination and ozonation methods on pure cultures of floc-forming micro-organisms and activated sludge: a comparative study |
title_full_unstemmed |
Effectiveness of chlorination and ozonation methods on pure cultures of floc-forming micro-organisms and activated sludge: a comparative study |
title_sort |
Effectiveness of chlorination and ozonation methods on pure cultures of floc-forming micro-organisms and activated sludge: a comparative study |
dc.creator.none.fl_str_mv |
Caravelli, Alejandro Horacio Giannuzzi, Leda Zaritzky, Noemí Elisabet |
author |
Caravelli, Alejandro Horacio |
author_facet |
Caravelli, Alejandro Horacio Giannuzzi, Leda Zaritzky, Noemí Elisabet |
author_role |
author |
author2 |
Giannuzzi, Leda Zaritzky, Noemí Elisabet |
author2_role |
author author |
dc.subject.none.fl_str_mv |
Química Filamentous bulking Chlorine Ozone INT-dehydrogenase activity Respirometry Image analysis Late count |
topic |
Química Filamentous bulking Chlorine Ozone INT-dehydrogenase activity Respirometry Image analysis Late count |
dc.description.none.fl_txt_mv |
Chlorination is a very useful control method of filamentous bulking in activated sludge systems; however, it favours formation; of undesirable compounds such as trihalomethanes. Other oxidants, such as ozone, could be used for bulking control. In view of the fact that chlorine and ozone are both non-selective chemical agents affecting filamentous and floc-forming micro-organisms, the determination of optimum dosage conditions becomes essential to minimise the impact produced on the activated sludge process. In this work, the effects of chlorine and ozone on the biomass concentration of activated sludge and on different parameters that characterise the microbial metabolic activity were compared. The following techniques were applied: Respirometry (oxygen uptake rate); and INT-dehydrogenase activity test carried out both by spectrophotometry (DHAa) and image analysis (DHAi). The respirometric technique and the DHAa test quantified oxidants action on the total respiratory activity of flocs; the image DHAi test was applied to evaluate the specific action of the oxidants on filamentous micro-organisms. Additionally, plate count technique, respirometry and DHAa test were correlated using chlorine and ozone experiments on pure cultures of a floc-forming micro-organism (Acinetobacter anitratus) to compare the effect of the oxidising; agents on the metabolic activity and the viability of the micro-organisms. Ozone was found to have more intense antimicrobial action. In activated sludge, ozone reduced total biomass concentration by oxidising various components and causing cell lysis. An equation was proposed to estimate biomass concentration of activated sludge as a function of time and ozone dose rate; in contrast, at the doses applied, chlorine did not reduce the concentration of activated sludge biomass. In activated sludge, adequate conditions for both oxidants were identified under which the respiratory activity of filamentous micro-organisms could be considerably inhibited, causing the lowest possible impact on whole floc metabolic activity. An initial chlorine dose of 7.9 mgCl2·gVSS-1 for a contact time of 5 min (initial pulse= 6.0 mgCl2·l-1), and a total ozone dose of 66.0 mgO3·gVSS-1 (ozone dose rate of 3.3 mgO3·gVSS-1·min-1 for a contact time of 20 min) were the most suitable conditions to control filamentous bulking. Centro de Investigación y Desarrollo en Criotecnología de Alimentos |
description |
Chlorination is a very useful control method of filamentous bulking in activated sludge systems; however, it favours formation; of undesirable compounds such as trihalomethanes. Other oxidants, such as ozone, could be used for bulking control. In view of the fact that chlorine and ozone are both non-selective chemical agents affecting filamentous and floc-forming micro-organisms, the determination of optimum dosage conditions becomes essential to minimise the impact produced on the activated sludge process. In this work, the effects of chlorine and ozone on the biomass concentration of activated sludge and on different parameters that characterise the microbial metabolic activity were compared. The following techniques were applied: Respirometry (oxygen uptake rate); and INT-dehydrogenase activity test carried out both by spectrophotometry (DHAa) and image analysis (DHAi). The respirometric technique and the DHAa test quantified oxidants action on the total respiratory activity of flocs; the image DHAi test was applied to evaluate the specific action of the oxidants on filamentous micro-organisms. Additionally, plate count technique, respirometry and DHAa test were correlated using chlorine and ozone experiments on pure cultures of a floc-forming micro-organism (Acinetobacter anitratus) to compare the effect of the oxidising; agents on the metabolic activity and the viability of the micro-organisms. Ozone was found to have more intense antimicrobial action. In activated sludge, ozone reduced total biomass concentration by oxidising various components and causing cell lysis. An equation was proposed to estimate biomass concentration of activated sludge as a function of time and ozone dose rate; in contrast, at the doses applied, chlorine did not reduce the concentration of activated sludge biomass. In activated sludge, adequate conditions for both oxidants were identified under which the respiratory activity of filamentous micro-organisms could be considerably inhibited, causing the lowest possible impact on whole floc metabolic activity. An initial chlorine dose of 7.9 mgCl2·gVSS-1 for a contact time of 5 min (initial pulse= 6.0 mgCl2·l-1), and a total ozone dose of 66.0 mgO3·gVSS-1 (ozone dose rate of 3.3 mgO3·gVSS-1·min-1 for a contact time of 20 min) were the most suitable conditions to control filamentous bulking. |
publishDate |
2006 |
dc.date.none.fl_str_mv |
2006 |
dc.type.none.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Articulo http://purl.org/coar/resource_type/c_6501 info:ar-repo/semantics/articulo |
format |
article |
status_str |
publishedVersion |
dc.identifier.none.fl_str_mv |
http://sedici.unlp.edu.ar/handle/10915/128235 |
url |
http://sedici.unlp.edu.ar/handle/10915/128235 |
dc.language.none.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
info:eu-repo/semantics/altIdentifier/issn/0378-4738 info:eu-repo/semantics/altIdentifier/doi/10.4314/wsa.v32i4.5283 |
dc.rights.none.fl_str_mv |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-sa/4.0/ Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) |
eu_rights_str_mv |
openAccess |
rights_invalid_str_mv |
http://creativecommons.org/licenses/by-nc-sa/4.0/ Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) |
dc.format.none.fl_str_mv |
application/pdf 585-595 |
dc.source.none.fl_str_mv |
reponame:SEDICI (UNLP) instname:Universidad Nacional de La Plata instacron:UNLP |
reponame_str |
SEDICI (UNLP) |
collection |
SEDICI (UNLP) |
instname_str |
Universidad Nacional de La Plata |
instacron_str |
UNLP |
institution |
UNLP |
repository.name.fl_str_mv |
SEDICI (UNLP) - Universidad Nacional de La Plata |
repository.mail.fl_str_mv |
alira@sedici.unlp.edu.ar |
_version_ |
1844616190409834496 |
score |
13.070432 |