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Air Gap Membrane Distillation Process Enhancement for Hypersaline Feed Solution by Application of Vacuum

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Resumo:This study investigated how the process performance of air gap membrane distillation be enhanced by the application of vacuum to treat hypersaline feed solutions. A vacuum-enhanced air-gap membrane distillation (V-AGMD) configuration was set up and sub-ambient pressure was applied in the air gap to remove non-condensable gases and reduce conductive heat transfer for enhancing the flux and thermal efficiency. The process was evaluated in comparison to the AGMD process while varying operational parameters such as the mean temperature (Tm), difference of temperature in heating and cooling streams (ΔT), flow velocity, and absolute air gap pressure. Initially, tap water was used as feed to set a baseline for the analysis of vapor pressure reduction incurred in hypersaline feed. Two commercial flat sheet PTFE membranes (pore size 0.1 μm and 0.2 μm) were tested. In the hypersaline feed experiments, two air gap widths (0.80 mm and 1.15 mm) were assessed in both ambient and vacuum conditions. Within the scope of this work, the operational conditions which yielded a reasonable trade-off between flux and thermal efficiency were considered optimal. These conditions were Tm 60 °C, ΔT 16 °C, flow velocity 0.1 m/s and absolute air gap pressure of 500 mbar for tap water experiments. For hypersaline feed experiments, the optimal conditions were Tm 60 °C, ΔT 16 °C, flow velocity 0.07 m/s and absolute air gap pressure of 350 mbar. A quantitative comparison between AGMD and V-AGMD setup showed that, for the determined optimal conditions using tap water, the flux improved by 37.6 %, and thermal efficiency improved by 17.7 %. For the hypersaline feed, the V-AGMD setup showed an enhancement of the flux by 279.5 % and thermal efficiency by 149.9 %. The results of this work proved that improving the performance of AGMD process is possible by deaeration of the airgap using vacuum and that V-AGMD is a viable option for treatment of hypersaline feeds.
Autores principais:Ashraf, Amna
Assunto:Vacuum-enhanced air-gap membrane distillation (V-AGMD) flat sheet membranes thermal efficiency hypersaline feed treatment
Ano:2021
País:Portugal
Tipo de documento:dissertação de mestrado
Tipo de acesso:acesso aberto
Instituição associada:Universidade Nova de Lisboa
Idioma:inglês
Origem:Repositório Institucional da UNL
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author Ashraf, Amna
author_facet Ashraf, Amna
author_role author
contributor_name_str_mv Schwantes, Rebecca
RUN
country_str PT
creators_json_txt [{\"Person.name\":\"Ashraf, Amna\"}]
datacite.contributors.contributor.contributorName.fl_str_mv Schwantes, Rebecca
RUN
datacite.creators.creator.creatorName.fl_str_mv Ashraf, Amna
datacite.date.Accepted.fl_str_mv 2021-07-23T00:00:00Z
datacite.date.available.fl_str_mv 2024-07-01T00:30:42Z
datacite.date.embargoed.fl_str_mv 2024-07-01T00:30:42Z
datacite.rights.fl_str_mv http://purl.org/coar/access_right/c_abf2
datacite.subjects.subject.fl_str_mv Vacuum-enhanced air-gap membrane distillation (V-AGMD)
flat sheet membranes
thermal efficiency
hypersaline feed treatment
datacite.titles.title.fl_str_mv Air Gap Membrane Distillation Process Enhancement for Hypersaline Feed Solution by Application of Vacuum
dc.contributor.none.fl_str_mv Schwantes, Rebecca
RUN
dc.creator.none.fl_str_mv Ashraf, Amna
dc.date.Accepted.fl_str_mv 2021-07-23T00:00:00Z
dc.date.available.fl_str_mv 2024-07-01T00:30:42Z
dc.date.embargoed.fl_str_mv 2024-07-01T00:30:42Z
dc.format.none.fl_str_mv application/pdf
dc.identifier.none.fl_str_mv http://hdl.handle.net/10362/124060
dc.language.none.fl_str_mv eng
dc.rights.none.fl_str_mv http://purl.org/coar/access_right/c_abf2
dc.subject.none.fl_str_mv Vacuum-enhanced air-gap membrane distillation (V-AGMD)
flat sheet membranes
thermal efficiency
hypersaline feed treatment
dc.title.fl_str_mv Air Gap Membrane Distillation Process Enhancement for Hypersaline Feed Solution by Application of Vacuum
dc.type.none.fl_str_mv http://purl.org/coar/resource_type/c_bdcc
description This study investigated how the process performance of air gap membrane distillation be enhanced by the application of vacuum to treat hypersaline feed solutions. A vacuum-enhanced air-gap membrane distillation (V-AGMD) configuration was set up and sub-ambient pressure was applied in the air gap to remove non-condensable gases and reduce conductive heat transfer for enhancing the flux and thermal efficiency. The process was evaluated in comparison to the AGMD process while varying operational parameters such as the mean temperature (Tm), difference of temperature in heating and cooling streams (ΔT), flow velocity, and absolute air gap pressure. Initially, tap water was used as feed to set a baseline for the analysis of vapor pressure reduction incurred in hypersaline feed. Two commercial flat sheet PTFE membranes (pore size 0.1 μm and 0.2 μm) were tested. In the hypersaline feed experiments, two air gap widths (0.80 mm and 1.15 mm) were assessed in both ambient and vacuum conditions. Within the scope of this work, the operational conditions which yielded a reasonable trade-off between flux and thermal efficiency were considered optimal. These conditions were Tm 60 °C, ΔT 16 °C, flow velocity 0.1 m/s and absolute air gap pressure of 500 mbar for tap water experiments. For hypersaline feed experiments, the optimal conditions were Tm 60 °C, ΔT 16 °C, flow velocity 0.07 m/s and absolute air gap pressure of 350 mbar. A quantitative comparison between AGMD and V-AGMD setup showed that, for the determined optimal conditions using tap water, the flux improved by 37.6 %, and thermal efficiency improved by 17.7 %. For the hypersaline feed, the V-AGMD setup showed an enhancement of the flux by 279.5 % and thermal efficiency by 149.9 %. The results of this work proved that improving the performance of AGMD process is possible by deaeration of the airgap using vacuum and that V-AGMD is a viable option for treatment of hypersaline feeds.
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institution Universidade Nova de Lisboa
instname_str Universidade Nova de Lisboa
language eng
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oai_identifier_str oai:run.unl.pt:10362/124060
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person_str_mv Ashraf, Amna
publishDate 2021
reponame_str Repositório Institucional da UNL
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spelling engpt_PTThis study investigated how the process performance of air gap membrane distillation be enhanced by the application of vacuum to treat hypersaline feed solutions. A vacuum-enhanced air-gap membrane distillation (V-AGMD) configuration was set up and sub-ambient pressure was applied in the air gap to remove non-condensable gases and reduce conductive heat transfer for enhancing the flux and thermal efficiency. The process was evaluated in comparison to the AGMD process while varying operational parameters such as the mean temperature (Tm), difference of temperature in heating and cooling streams (ΔT), flow velocity, and absolute air gap pressure. Initially, tap water was used as feed to set a baseline for the analysis of vapor pressure reduction incurred in hypersaline feed. Two commercial flat sheet PTFE membranes (pore size 0.1 μm and 0.2 μm) were tested. In the hypersaline feed experiments, two air gap widths (0.80 mm and 1.15 mm) were assessed in both ambient and vacuum conditions. Within the scope of this work, the operational conditions which yielded a reasonable trade-off between flux and thermal efficiency were considered optimal. These conditions were Tm 60 °C, ΔT 16 °C, flow velocity 0.1 m/s and absolute air gap pressure of 500 mbar for tap water experiments. For hypersaline feed experiments, the optimal conditions were Tm 60 °C, ΔT 16 °C, flow velocity 0.07 m/s and absolute air gap pressure of 350 mbar. A quantitative comparison between AGMD and V-AGMD setup showed that, for the determined optimal conditions using tap water, the flux improved by 37.6 %, and thermal efficiency improved by 17.7 %. For the hypersaline feed, the V-AGMD setup showed an enhancement of the flux by 279.5 % and thermal efficiency by 149.9 %. The results of this work proved that improving the performance of AGMD process is possible by deaeration of the airgap using vacuum and that V-AGMD is a viable option for treatment of hypersaline feeds.application/pdfpt_PTAir Gap Membrane Distillation Process Enhancement for Hypersaline Feed Solution by Application of VacuumAshraf, AmnaSchwantes, RebeccaHostingInstitutionOrganizationalRUNe-mailmailto:run@unl.ptrun@unl.pt2024-07-01T00:30:42Z2021-07-232021-07-23T00:00:00ZHandlehttp://hdl.handle.net/10362/124060http://purl.org/coar/access_right/c_abf2open accessVacuum-enhanced air-gap membrane distillation (V-AGMD)flat sheet membranesthermal efficiencyhypersaline feed treatment3551782 bytesliteraturehttp://purl.org/coar/resource_type/c_bdccmaster thesishttp://purl.org/coar/access_right/c_abf2application/pdffulltexthttps://run.unl.pt/bitstreams/0db4e542-8f56-492b-af9e-d75a50a6bdca/download
spellingShingle Air Gap Membrane Distillation Process Enhancement for Hypersaline Feed Solution by Application of Vacuum
Ashraf, Amna
Vacuum-enhanced air-gap membrane distillation (V-AGMD)
flat sheet membranes
thermal efficiency
hypersaline feed treatment
status SINGLETON
subject.fl_str_mv Vacuum-enhanced air-gap membrane distillation (V-AGMD)
flat sheet membranes
thermal efficiency
hypersaline feed treatment
title Air Gap Membrane Distillation Process Enhancement for Hypersaline Feed Solution by Application of Vacuum
title_full Air Gap Membrane Distillation Process Enhancement for Hypersaline Feed Solution by Application of Vacuum
title_fullStr Air Gap Membrane Distillation Process Enhancement for Hypersaline Feed Solution by Application of Vacuum
title_full_unstemmed Air Gap Membrane Distillation Process Enhancement for Hypersaline Feed Solution by Application of Vacuum
title_short Air Gap Membrane Distillation Process Enhancement for Hypersaline Feed Solution by Application of Vacuum
title_sort Air Gap Membrane Distillation Process Enhancement for Hypersaline Feed Solution by Application of Vacuum
topic Vacuum-enhanced air-gap membrane distillation (V-AGMD)
flat sheet membranes
thermal efficiency
hypersaline feed treatment
topic_facet Vacuum-enhanced air-gap membrane distillation (V-AGMD)
flat sheet membranes
thermal efficiency
hypersaline feed treatment
url http://hdl.handle.net/10362/124060
visible 1