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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Reduzierung der Keim- und Staubbelastung der Stallluft in der Schweinehaltung mit UVC-kombinierter Umluftfiltration

Eisenlöffel, Lisa 07 June 2022 (has links)
Einige Krankheitserreger, die für hohe wirtschaftliche Verluste in der Schweineindustrie sorgen, können über mehrere Kilometer über die Luft übertragen werden. Staub und daran gebundene Mikroorganismen können sowohl bei Tieren, als auch bei Menschen, die in der Landwirtschaft arbeiten, zu gesundheitlichen Beeinträchtigungen führen. Um den aerogenen Erregereintrag und die Belastung der Gesundheit durch Stallstaub zu reduzieren, können Filtertechniken, wie Umluftfiltration, zum Einsatz kommen. In mehreren Studien konnte beim Einsatz von Umluftfiltration im Schweinestall ein positiver Einfluss auf die Lungengesundheit der Tiere verzeichnet werden. Auf diesen Erkenntnissen aufbauend, war es Gegenstand dieser Arbeit die positiven Effekte der Umluftfiltration mit der keimtötenden Wirkung von UVC-Strahlen zu kombinieren und somit den Keimgehalt der Stallluft zu reduzieren. Das Ziel der vorliegenden Arbeit war es, die Effizienz von UVC-kombinierter Umluftfiltration hinsichtlich der Reduktionsrate luftgetragener Mikroorganismen im Labormaßstab zu untersuchen. Im zweiten Teil der Studie wurde ein UVC-Umluftfiltermodul in einen kleinen Stall integriert, um dessen Einfluss auf die Qualität der Stallluft bzw. auf die Staub- und Bakterienmenge im Vergleich zu einem Referenzstall zu überprüfen. Für Testdurchläufe im Labormaßstab wurden Aerosole mit Staphylococcus aureus, Ac-tinobacillus pleuropneumoniae, dem Virus des seuchenhaften Spätaborts (PRRSV) und dem Porcinen Parvovirus (PPV) erzeugt. In einem Luftfilterprüfstand wurden mit jedem Erreger je fünf unabhängige Testläufe mit und ohne UVC-Bestrahlung durchgeführt. Bei einigen Test-durchläufen wurde die relative Luftfeuchtigkeit (rLF) verändert, um den Einfluss einer erhöh-ten rLF auf die UVC-Wirksamkeit zu bewerten. Die Reduktionsrate entsprach der Differenz der infektiösen Partikel gemessen vor dem Luftfilter und hinter dem Luftfilter. Um das Überleben von Krankheitserregern im Filtermaterial zu untersuchen, wurden die Filter in ge-trennten Plastiktüten aufbewahrt. Nach bestimmten Zeitintervallen wurden Filterproben ent-nommen, gepoolt und inkubiert. Es folgte eine Virustitration bzw. eine Zählung der Bakterien. Die Feldstudie fand in einem kleinen Instituts-eigenen Stall statt, der aus zwei getrennten Stallabteilen bestand. Es wurden wöchentlich Luftmessungen über einen Zeitraum von 13 Wochen bzw. 16 Wochen in jedem Stallabteil durchgeführt. Die Staub- und Bakterienmenge der Stallluft wurde an drei verschiedenen Probennahmestellen gemessen. Zusätzlich wurden Luft-Proben direkt vor und hinter dem UVC-Modul entnommen. Weiterhin wurde die Ammoniak- und CO2-Konzentration, sowie Temperatur und rLF aufgezeichnet. Die Reduktionsraten der Staub- und Bakterienmenge der Stallluft wurde durch Berechnung der Werteverhältnisse (Ratios) der Messwerte aus Stall 1 (UVC-Modul) verglichen zu Stall 2 (Referenzstall) bestimmt. Ratios kleiner als eins entsprachen einer relativen Verringerung der Bakterienzahl bzw. Staubmenge. Durch logarithmische Transformierung der Ratios wurden annähernd normalverteilte Werte gewährleistet. Unter Verwendung eines t-Tests mit einer Probe auf einem Signifikanzniveau von 5 % wurden Nullhypothesen von unveränderten mittleren Bakterien- bzw. Staubwerten geprüft. Zusätzlich wurden 95 %ige Konfidenzintervalle für die geschätzten Stichprobenmittelwerte berechnet. Bei Tests im Labormaßstab führte das UVC-kombinierte Filtersystem zu einer Reduzierung der viralen und bakteriellen Partikel um mehr als 99 %. Die rLF hatte keinen Einfluss auf die UVC-Effizienz. Die Lebensfähigkeit der Pathogene im Filtermaterial variierte in Abhängigkeit vom verwendeten Pathogen und der rLF, wobei sich S. aureus und PPV am resistentesten darstellten. In der Feldstudie erreichten wir in der Stallluft von Stall 1 (mit dem UVC-Modul) eine signifikant niedrigere Bakterienmenge im Vergleich zum Referenzstall (Stall 2). Die Bakterienkonzentration der Stallluft konnte durchschnittlich auf 37 % reduziert werden, während die Staubmenge in viel geringerem Maße (auf 78 %) verringert werden konnte. Messungen unmittelbar vor und hinter dem UVC-Modul ergaben in der Stallluft eine Reduktion von 99,4 % für Bakterien und von 95,0 % für Staub. Wir konnten die Wirksamkeit von UVC-Strahlung zur Luftdesinfektion im Labormaßstab mit einer Reduktionseffizienz von >99 % für ausgewählte Viren und Bakterien erfolgreich demonstrieren. Darüber hinaus erwies sich die Kombination von UVC-Strahlung und Umluftfiltration als erfolgreich bei der Reduzierung der Bakterien- und Staubmenge der Stallluft in einem kleinen Schweinbestand. Der Einsatz dieser Technologie könnte die allgemeine Stallluftqualität in Nutztierställen verbessern.:1 Einleitung 2 Literaturübersicht 2.1 Ausgewählte Pathogene in der Schweinehaltung 2.1.1 Viren 2.1.1.1 Porcine reproductive and respiratory syndrome virus (PRRSV) 2.1.1.2 Ungulate protoparvovirus 1 (Porcines Parvovirus, PPV) 2.1.2 Bakterien 2.1.2.1 Actinobacillus pleuropneumoniae (APP) 2.1.2.2 Methicillin-resistente Staphylococcus aureus (MRSA) 2.2 UVC-Strahlung 2.2.1 Allgemeines 2.2.2 Luftdesinfektion mit UVC-Strahlung 2.3 Luftfiltration 2.3.1 Grundlagen der Filtration 2.3.2 Filterklassen 2.3.3 Luftfiltration in der Tierhaltung 2.4 Stallklima 2.4.1 Zusammensetzung der Stallluft 2.4.1.1 Organische Komponenten 2.4.1.1.1 Staub 2.4.1.1.2 Mikrobielle Zusammensetzung der Stallluft 2.4.1.2 Chemische und physikalische Komponenten 2.4.1.2.1 Temperatur, relative Luftfeuchtigkeit (rLF), Luftgeschwindigkeit 2.4.1.2.2 Ammoniak (NH3) 2.4.1.2.3 Kohlendioxid (CO2) 3 Veröffentlichung 3.1 Eigenanteil 3.2 Fremdanteil 4 Diskussion 5 Zusammenfassung 6 Summary Literaturverzeichnis Danksagung / Some pathogens, which cause high economic losses in the swine industry, can be transmitted over several kilometres via the airborne route. Dust and microorganisms bound to dust can lead to serious health problems for animals, as well as for human beings working in the agricultural environment. In order to reduce airborne pathogen burden and to lower the negative health impact of stable dust, air filtration technologies such as recirculating air filtration can be used. In several studies, a positive impact on swine lung health was seen, when recirculating air filtration was implemented in the pig barn. Filtration of supply air can minimize the risk of introducing airborne pathogens to indoor air. Based on this knowledge, the aim of this study was to combine the positive effects of recirculating air filtration with the germicidal effect of UVC-irradiation, and thus to reduce germ content of stable air. The aim of the current study was, to assess the efficiency of UVC irradiation combined to air filtration in reducing airborne microorganisms at laboratory scale. In a second part, a UVC-combined recirculating air filtration module (UVC module) was implemented in a small animal facility in order to assess its improvement of air quality with regard to airborne bacteria and dust. Tests at laboratory scale were performed using aerosols of Staphylococcus aureus, Actinobacillus pleuropneumoniae, porcine reproductive and respiratory syndrome virus (PRRSV) and porcine parvovirus (PPV). Five independent test runs were performed in a test chamber with each pathogen, with and without UVC irradiation, respectively. Relative humidity (RH) was manipulated in some test runs to evaluate the influence of increased RH to UVC-efficacy. Reduction efficiencies were calculated by numbers of pathogens entering and leaving the test chamber. To investigate the survival of pathogens in the filter material, the filters were stored in separated plastic bags. Filter samples were taken after certain time intervals, pooled and incubated, followed by virus titration or counting of bacteria. Our field study occurred in a small pig facility consisting of two separated barns. Weekly air measurements were conducted over a period of 13 weeks (10 piglets) and 16 weeks (11 piglets) in each barn, respectively. Airborne dust and bacteria amount was sampled and calculated at three different sampling points. Furthermore, samples were taken right in front and behind the UVC-module. In addition, ammonia, CO2, temperature and RH were recorded. Relative reduction of airborne dust and bacteria amount was determined by calculating ratios of values in barn 1 (UVC-module) compared to barn 2 (reference). Ratios smaller than one correspond to a relative reduction of bacterial counts/dust amount. Ratios were log-transformed to guarantee approximately normally distributed values. Null hypotheses of unchanged mean bacterial or dust counts (i.e., mean ratios equal one) were tested using one sample t-tests on a significance level of 5 %. In addition, 95 % confidence intervals (CI) were calculated for the estimated sample means. UVC-combined air filtration in tests at laboratory scale resulted in a more than 99 % reduction of viral and bacterial particles. RH had no influence on UVC efficiency. Viability in the filter matter varied depending on the pathogen used and RH with S. aureus and PPV being most resistant. In the field study, airborne bacterial numbers were significantly lower in the barn equipped with the UVC module compared to the reference barn. On average, a reduction to 37 % of reference values could be achieved for bacteria, whereas the amount of total dust was reduced to a much lesser extent (i.e. to 78 % of reference values). Measures taken in front of and behind the UVC module revealed a reduction of 99.4 % for airborne bacteria and 95.0 % for total dust. We successfully demonstrated the effectiveness of air disinfection using UVC irradiation at laboratory scale with reduction efficiencies of >99 % for certain viruses and bacteria. Moreo-ver, combining UVC irradiation to recirculating air filtration proved to be successful in reduc-ing airborne bacteria and dust in a small animal facility. The implementation of such devices might improve the overall environmental quality in animal facilities.:1 Einleitung 2 Literaturübersicht 2.1 Ausgewählte Pathogene in der Schweinehaltung 2.1.1 Viren 2.1.1.1 Porcine reproductive and respiratory syndrome virus (PRRSV) 2.1.1.2 Ungulate protoparvovirus 1 (Porcines Parvovirus, PPV) 2.1.2 Bakterien 2.1.2.1 Actinobacillus pleuropneumoniae (APP) 2.1.2.2 Methicillin-resistente Staphylococcus aureus (MRSA) 2.2 UVC-Strahlung 2.2.1 Allgemeines 2.2.2 Luftdesinfektion mit UVC-Strahlung 2.3 Luftfiltration 2.3.1 Grundlagen der Filtration 2.3.2 Filterklassen 2.3.3 Luftfiltration in der Tierhaltung 2.4 Stallklima 2.4.1 Zusammensetzung der Stallluft 2.4.1.1 Organische Komponenten 2.4.1.1.1 Staub 2.4.1.1.2 Mikrobielle Zusammensetzung der Stallluft 2.4.1.2 Chemische und physikalische Komponenten 2.4.1.2.1 Temperatur, relative Luftfeuchtigkeit (rLF), Luftgeschwindigkeit 2.4.1.2.2 Ammoniak (NH3) 2.4.1.2.3 Kohlendioxid (CO2) 3 Veröffentlichung 3.1 Eigenanteil 3.2 Fremdanteil 4 Diskussion 5 Zusammenfassung 6 Summary Literaturverzeichnis Danksagung
22

Analyzing the adaption of energy optimization modules in HVAC systems : A case study within Sweden’s commercial market

Tiwari, Shashank Prasad, Potluri, Sumanth January 2020 (has links)
This study has been motivated by an understanding of the twin needs to reduce carbon dioxide emissions and increase the access to have complete control of the ventilation system available in the buildings. In consideration of the increasing utilization of fossil fuels, there is an extensive threat of increased global warming conditions associated. To ensure sustainable development, improvement of social welfare and wealth creation, energy is an essential factor. The consumption of electricity and energy delivered per floor area in Sweden has been considerably rising since 2014. The aim of this study is twofold where the authors have mapped and defined the specific customer needs for choosing an “add-on energy optimization module” for the existing HVAC systems in Sweden’s commercial market. Secondly, the study has also focussed to identify the acceptance of the complementary good technology from the perspective of a customer’s experience of value creation. It is a case study carried out in collaboration with a Swedish cleantech company, that will be named “Company-X” in the further part of the study. This company utilises a part of space technology to secure a healthy indoor air climate and at the same time save energy in buildings. The thesis has been carried out qualitatively. Since there is a preunderstanding of this theory where an abductive approach with semi-structured interviews has been followed to perceive the current market situation. The study further underlines the importance and need of making investments for a cleaning module combined with an optimization algorithm which can be easily mounted on current ventilation systems like Lego pieces. Under this module, the air quality is monitored, and the system adapts to current conditions concerning time. The results designate that it is possible to maintain a predefined indoor air quality to the lowest possible energy consumption by real-time monitoring with this cleaning module at facilities that are equipped with single or multiple-split HVAC systems. The best results towards attaining greater energy savings can be obtained from the association of Building energy management system and Air-handling unit with this cleaning module.
23

Medidas utilizadas na prevenção de infecções em transplante de células-tronco hematopoéticas: evidências para a prática / Infection prevention measures used in hematopoietic stem cell transplantation: evidences for practice

Garbin, Livia Maria 30 June 2010 (has links)
O transplante de células-tronco hematopoéticas (TCTH) consiste em um procedimento complexo e relacionado à ocorrência de diversas complicações, dentre elas os processos infecciosos decorrentes do longo período de imunossupressão vivenciado após a instituição do regime de condicionamento. Inúmeras medidas têm sido empregadas visando à prevenção e controle de infecções, porém, observam-se divergências em relação à utilização das mesmas; sendo que o emprego da prática baseada em evidências possibilita ao profissional tomar decisões em relação à sua prática fundamentadas em resultados de pesquisas científicas atuais. Esta revisão integrativa da literatura teve como objetivo identificar e avaliar as evidências disponíveis na literatura e publicadas nos últimos 20 anos em relação ao uso de três medidas de prevenção de infecção em pacientes submetidos ao TCTH durante o período de internação: uso de filtros de ar de alta eficiência, isolamento protetor e máscaras. Para a seleção dos artigos foram utilizadas as bases de dados LILACS, PUBMED, CINAHL, EMBASE e a Biblioteca Cochrane. A amostra foi composta por 15 estudos, sendo que apenas um apresentou nível de evidência forte (nível I), dois apresentaram nível de evidência moderado (nível IV e V) e doze consistiram em estudos com evidências fracas (nível VI e VII). Dez estudos abordaram a utilização dos filtros HEPA, sendo recomendado seu emprego para pacientes submetidos ao transplante alogênico durante o período de neutropenia. A necessidade de seu uso para pacientes submetidos ao transplante autólogo ainda é controversa. Nove trabalhos abordaram o uso do isolamento protetor e, embora alguns autores relatem que o emprego do mesmo parece apresentar benefícios quando não se dispõe de filtros HEPA, a utilização desta medida já não é mais indicada tanto pelos Centers for Disease Control and Prevention (CDC) quanto pela maioria dos estudos analisados. Em relação à utilização de máscaras por pacientes, profissionais de saúde ou visitantes dentro das unidades de internação para TCTH, não foram encontrados estudos com evidências fortes que justifiquem o seu uso. No entanto, recomenda-se que sejam seguidas as diretrizes dos CDC quanto ao uso de respiradores especiais (como as máscaras N95) pelos pacientes imunocomprometidos submetidos ao TCTH ao deixar a unidade de transplante provida de filtro HEPA quando próximo a ela houver áreas de construção/reforma ou atividades geradoras de poeira. Embora os dados evidenciados auxiliem na tomada de decisão para a implementação da assistência de enfermagem a estes pacientes, verificou-se a necessidade de realização de estudos com nível de evidência forte que comprovem ou refutem a efetividade destas medidas. / Hematopoietic stem cell transplantation (HSCT) is a complex procedure related to the occurrence of different complications, including infectious processes deriving from the long period of immunosuppression experienced after the establishment of the conditioning regimen. Countless measures have been used for infection prevention and control, but divergences are observed with regard to their use; evidence-based practice allows professionals to make decisions for practice based on current scientific research results. This integrative literature review aimed to identify and assess evidence available in literature and published in the last 20 years about the use of three infection prevention measures in patients submitted to HSCT during hospitalization: use of high-efficiency air filters, protective isolation and masks. LILACS, PUBMED, CINAHL, EMBASE and the Cochrane Library were used to select the articles. The sample comprised 15 studies, only one of which presented strong evidence (level I), while two presented moderate evidence (levels IV and V) and twelve were studies with weak evidence (levels VI and VII). Ten studies discussed the use of HEPA filters, recommended for patients submitted to allogeneic transplantation during the neutropenia period. It remains controversial whether these filters need to be used for patients submitted to autologous transplant. Nine studies addressed the use of protective isolation and, although some authors report that using this measure can be beneficial when HEPA filters are unavailable, neither the Centers for Disease Control and Prevention (CDC) nor by most of the studies under analysis indicate it any longer. With regard to the use of masks by patients, health professionals or visitors inside HSCT hospitalization units, no studies with strong evidence were found that justify its use. However, it is recommended that CDC recommendations be followed regarding the use of special respirators (like N95 masks) by immunocompromised patients submitted to HSCT when they leave the transplantation unit with a HEPA filter in case of nearby construction/reform areas or activities that generate dust. Although the evidenced data support decision making with a view to nursing care delivery to these patients, research with strong evidence is needed to prove or reject the efficacy of these measures.
24

Medidas utilizadas na prevenção de infecções em transplante de células-tronco hematopoéticas: evidências para a prática / Infection prevention measures used in hematopoietic stem cell transplantation: evidences for practice

Livia Maria Garbin 30 June 2010 (has links)
O transplante de células-tronco hematopoéticas (TCTH) consiste em um procedimento complexo e relacionado à ocorrência de diversas complicações, dentre elas os processos infecciosos decorrentes do longo período de imunossupressão vivenciado após a instituição do regime de condicionamento. Inúmeras medidas têm sido empregadas visando à prevenção e controle de infecções, porém, observam-se divergências em relação à utilização das mesmas; sendo que o emprego da prática baseada em evidências possibilita ao profissional tomar decisões em relação à sua prática fundamentadas em resultados de pesquisas científicas atuais. Esta revisão integrativa da literatura teve como objetivo identificar e avaliar as evidências disponíveis na literatura e publicadas nos últimos 20 anos em relação ao uso de três medidas de prevenção de infecção em pacientes submetidos ao TCTH durante o período de internação: uso de filtros de ar de alta eficiência, isolamento protetor e máscaras. Para a seleção dos artigos foram utilizadas as bases de dados LILACS, PUBMED, CINAHL, EMBASE e a Biblioteca Cochrane. A amostra foi composta por 15 estudos, sendo que apenas um apresentou nível de evidência forte (nível I), dois apresentaram nível de evidência moderado (nível IV e V) e doze consistiram em estudos com evidências fracas (nível VI e VII). Dez estudos abordaram a utilização dos filtros HEPA, sendo recomendado seu emprego para pacientes submetidos ao transplante alogênico durante o período de neutropenia. A necessidade de seu uso para pacientes submetidos ao transplante autólogo ainda é controversa. Nove trabalhos abordaram o uso do isolamento protetor e, embora alguns autores relatem que o emprego do mesmo parece apresentar benefícios quando não se dispõe de filtros HEPA, a utilização desta medida já não é mais indicada tanto pelos Centers for Disease Control and Prevention (CDC) quanto pela maioria dos estudos analisados. Em relação à utilização de máscaras por pacientes, profissionais de saúde ou visitantes dentro das unidades de internação para TCTH, não foram encontrados estudos com evidências fortes que justifiquem o seu uso. No entanto, recomenda-se que sejam seguidas as diretrizes dos CDC quanto ao uso de respiradores especiais (como as máscaras N95) pelos pacientes imunocomprometidos submetidos ao TCTH ao deixar a unidade de transplante provida de filtro HEPA quando próximo a ela houver áreas de construção/reforma ou atividades geradoras de poeira. Embora os dados evidenciados auxiliem na tomada de decisão para a implementação da assistência de enfermagem a estes pacientes, verificou-se a necessidade de realização de estudos com nível de evidência forte que comprovem ou refutem a efetividade destas medidas. / Hematopoietic stem cell transplantation (HSCT) is a complex procedure related to the occurrence of different complications, including infectious processes deriving from the long period of immunosuppression experienced after the establishment of the conditioning regimen. Countless measures have been used for infection prevention and control, but divergences are observed with regard to their use; evidence-based practice allows professionals to make decisions for practice based on current scientific research results. This integrative literature review aimed to identify and assess evidence available in literature and published in the last 20 years about the use of three infection prevention measures in patients submitted to HSCT during hospitalization: use of high-efficiency air filters, protective isolation and masks. LILACS, PUBMED, CINAHL, EMBASE and the Cochrane Library were used to select the articles. The sample comprised 15 studies, only one of which presented strong evidence (level I), while two presented moderate evidence (levels IV and V) and twelve were studies with weak evidence (levels VI and VII). Ten studies discussed the use of HEPA filters, recommended for patients submitted to allogeneic transplantation during the neutropenia period. It remains controversial whether these filters need to be used for patients submitted to autologous transplant. Nine studies addressed the use of protective isolation and, although some authors report that using this measure can be beneficial when HEPA filters are unavailable, neither the Centers for Disease Control and Prevention (CDC) nor by most of the studies under analysis indicate it any longer. With regard to the use of masks by patients, health professionals or visitors inside HSCT hospitalization units, no studies with strong evidence were found that justify its use. However, it is recommended that CDC recommendations be followed regarding the use of special respirators (like N95 masks) by immunocompromised patients submitted to HSCT when they leave the transplantation unit with a HEPA filter in case of nearby construction/reform areas or activities that generate dust. Although the evidenced data support decision making with a view to nursing care delivery to these patients, research with strong evidence is needed to prove or reject the efficacy of these measures.
25

Vzduchotechnika knihovny / Air conditioning in the library

Pospíšilová, Lucie January 2018 (has links)
Dissertation offers a plan for air – conditioning equipment of library building in Brno and it involves air filter experimental measurement. The proposal is divided into three parts. The first part explains air filter theory with detailed description of atmospheric air filters for separation of particles for general ventilation - filter parameter determination. Theory part ends specifically with pocket air filters and their construction. The second part focuses on experimental pocket air filter measurement execution, which calculates with variable filter cartridges and pocket count. Measurement also evaluates pressure drop and their efficiency. The last part of the dissertation looks at air – conditioning equipment design for specified building, concretely library building. The project solves fresh air traffic into interior of selected library rooms and it counts with thermal heat gain in summer season, heat loss in winter season and air humidity modification.
26

Nanofiber Filter Media for Air Filtration

Raghavan, Bharath Kumar 11 August 2010 (has links)
No description available.
27

The Biowall Field Test Analysis and Optimization

Jacob J. Torres (5930906) 14 May 2019 (has links)
<div> <p>A residential botanical air filtration system (Biowall) to investigate the potential for using phytoremediation to remove contaminants from indoor air was developed. A full scale and functioning prototype was installed in a residence located in West Lafayette, Indiana. The prototype was integrated into the central Heating, Ventilating, and Air Conditioning (HVAC) system of the home. This research evaluated the Biowall operation to further its potential as an energy efficient and sustainable residential air filtration system.<br></p> <p> </p> <p>The main research effort began after the Biowall was installed in the residence. A field evaluation, which involved a series of measurements and data analysis, was conducted to identify treatments to improve Biowall performance. The study was conducted for approximately one year (Spring 2017-Spring 2018). Based on the initial data set, prioritization of systems in need of improvement was identified and changes were imposed. Following a post-treatment testing period, a comparison between the initial and final performances was completed with conclusions based on this comparison. </p> <p> </p> <p>The engineering and analysis reported in this document focus on the air flow path through the Biowall, plant growth, and the irrigation system. The conclusions provide an extensive evaluation of the design, operation, and function of the Biowall subsystems under review.</p> </div> <br>
28

Application of Polymeric Hollow-Fiber Membranes in Air Filtration / Application of Polymeric Hollow-Fiber Membranes in Air Filtration

Bulejko, Pavel January 2019 (has links)
Membrány z dutých vláken jsou široce využívány v aplikacích týkajících se úpravy kapalin jako např. při čištění odpadních vod, v membránových kontaktorech a bioreaktorech, membránové destilaci apod. I když jsou často využívány při separacích směsí plynů, je jejich použití pro mechanickou filtraci aerosolů velmi vzácné. Tato práce se zabývá filtrací vzduchu pomocí polypropylenových membrán z dutých vláken včetně jejich filtrační účinnosti, tlakových ztrát a také zanášením při dlouhodobé filtraci. Filtrační účinnost byla proměřena za použití různých aerosolů jako TiO2 a síran amonný. Tlakové ztráty byly měřeny při různých konfiguracích, tj. různé filtrační ploše a průměru vlákna membrány. Zanášení membrán bylo testováno použitím normovaného prachu definovaného normou ANSI/ASHRAE 52.2. Predikční modely pro filtrační účinnost a permeabilitu/tlakovou ztrátu membrány byly aplikovány na parametry membrán z dutých vláken a porovnány. Tyto membrány mají velikost pórů kolem 90 nm a poměrně nízkou porositu a tím vysoký potenciál pro separaci nanočástic ze vzduchu. Dále byla provedena analýza filtračního koláče a vyhodnocení energetických nároků a porovnány s teoretickými modely. V závěru práce je nastíněn odhad ceny životního cyklu při filtraci pomocí těchto membrán.

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