LCA av dricksvattendesinfektion
Disinfection methods for drinking-water produced at the two water works of Stockholm Water Co are compared in this study. Three different nethods are compared; disinfection with chlorine gas, disinfection with sodium hypochlorite and disinfection with UV-light and monochloramine. The method used is...
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| Formato: | Otro |
| Lenguaje: | sueco sueco |
| Publicado: |
2005
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| Materias: | |
| Acceso en línea: | https://stud.epsilon.slu.se/12641/ |
| _version_ | 1855572104672444416 |
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| author | Ekvall, Cecilia |
| author_browse | Ekvall, Cecilia |
| author_facet | Ekvall, Cecilia |
| author_sort | Ekvall, Cecilia |
| collection | Epsilon Archive for Student Projects |
| description | Disinfection methods for drinking-water produced at the two water works of Stockholm Water Co are compared in this study. Three different nethods are compared; disinfection with chlorine gas, disinfection with sodium hypochlorite and disinfection with UV-light and monochloramine. The method used is Life cycle assessment, LCA. LCA is defined as the compilation and evaluation of the inputs, outputs and potential environmental impact of a product system shroughout its life cycle. The environmental burden is compared for the three different disinfection methods. Potential health effects and the working environment are also included.
One disadvantage with chlorination is the production of unwanted by-products when the free chlorine reacts with organic matter. These by-products, e.g. trihalomethans, THM, have shown to bee carcinogenic. This was one of the reasons that contributed to the changeover to disinfection with UV-light, at one of the two outgoing lines at Lovö water works. The UV-disinfection makes it possible to ure half of the ordinary dose of chlorine, it also lowers the amount of THM in the drinking water with 90%. (Blomberg et al. 2001)
UV-disinfection also led to increased bacterial reduction compared to chlorination. Another positive aspect is that the risks with handling of chlorine gas are reduced. Chlorine gas is an acute toxic gas that is hard to handle with regard to the working environment.
Results from the LCA show that disinfection with UV-light and monochloramin is about 45% more energy demanding than the other alternatives. The total use of energy with UV-disinfection is equal to 0.5-1% of the total energy required to produce and distribute the drinking water. Regarding to the environmental impacts the alternative with UV-disinfection contributes to the most amounts of greenhouse gases. The contribution of emissions that led to eutrofication and acidification dominates by the alternative with disinfection with hypochlorite.
To compare the human toxic risks two different methods has been used. According to the first method, USES-LCA, the biggest human toxic risks occurs with disinfection with hypochlorite and chlorine gas. With the other method, EDIP, the greatest risks occurs with disinfection with hypochlorite and disinfection with UV-light.
The positive effects of the changeover to UV-disinfection are received at the expense of higher energy consumption. Thich alternative to prefer are decided by how the values are made between the studied parts; energy- and environmental aspects verses health aspects and the working environment. |
| format | Otro |
| id | RepoSLU12641 |
| institution | Swedish University of Agricultural Sciences |
| language | Swedish swe |
| publishDate | 2005 |
| publishDateSort | 2005 |
| record_format | eprints |
| spelling | RepoSLU126412017-10-23T12:00:23Z https://stud.epsilon.slu.se/12641/ LCA av dricksvattendesinfektion Ekvall, Cecilia Water resources and management Faculty of Natural Resources and Agricultural Sciences (until 2013) Disinfection methods for drinking-water produced at the two water works of Stockholm Water Co are compared in this study. Three different nethods are compared; disinfection with chlorine gas, disinfection with sodium hypochlorite and disinfection with UV-light and monochloramine. The method used is Life cycle assessment, LCA. LCA is defined as the compilation and evaluation of the inputs, outputs and potential environmental impact of a product system shroughout its life cycle. The environmental burden is compared for the three different disinfection methods. Potential health effects and the working environment are also included. One disadvantage with chlorination is the production of unwanted by-products when the free chlorine reacts with organic matter. These by-products, e.g. trihalomethans, THM, have shown to bee carcinogenic. This was one of the reasons that contributed to the changeover to disinfection with UV-light, at one of the two outgoing lines at Lovö water works. The UV-disinfection makes it possible to ure half of the ordinary dose of chlorine, it also lowers the amount of THM in the drinking water with 90%. (Blomberg et al. 2001) UV-disinfection also led to increased bacterial reduction compared to chlorination. Another positive aspect is that the risks with handling of chlorine gas are reduced. Chlorine gas is an acute toxic gas that is hard to handle with regard to the working environment. Results from the LCA show that disinfection with UV-light and monochloramin is about 45% more energy demanding than the other alternatives. The total use of energy with UV-disinfection is equal to 0.5-1% of the total energy required to produce and distribute the drinking water. Regarding to the environmental impacts the alternative with UV-disinfection contributes to the most amounts of greenhouse gases. The contribution of emissions that led to eutrofication and acidification dominates by the alternative with disinfection with hypochlorite. To compare the human toxic risks two different methods has been used. According to the first method, USES-LCA, the biggest human toxic risks occurs with disinfection with hypochlorite and chlorine gas. With the other method, EDIP, the greatest risks occurs with disinfection with hypochlorite and disinfection with UV-light. The positive effects of the changeover to UV-disinfection are received at the expense of higher energy consumption. Thich alternative to prefer are decided by how the values are made between the studied parts; energy- and environmental aspects verses health aspects and the working environment. Detta är en jämförande studie av desinfektionsmetoder för dricksvatten framställt vid Stockholm Vattens två vattenverk. Jämförelse sker mellan tre olika metoder; desinfektion med klorgas, desinfektion med natriumhypoklorit samt desinfektion med UV-ljus. Metodiken som används är livscykelanalys. Jämförelsen är gjord med avseende på miljöpåverkan och energianvändning för de tre olika desinfektionsmetoderna. Dessutom har även eventuella skillnader i hälsoeffekter samt arbetsmiljö undersökts. En betydande nackdel med klorering är att det bildas oönskade biprodukter när det fria kloret reagerar med organiska föreningar. Dessa biprodukter, bl.a. trihalometaner har visats vara cancerogena. Detta var en av faktorerna som bidrog till en övergång till UV-desinfektion på en av de två utgående linjerna från Lovö vattenverk. UV-desinfektion möjliggör en halvering av klordosen vilket leder till att mängden THM i utgående dricksvatten kan minskas med hela 90% i jämförelse med dagens klorerade dricksvatten (Blomberg m.fl., 2001). UV-desinfektion medför även en större bakteriereduktion jämfört med klorering. En annan positiv aspekt är att hanteringen av klorgas undviks. Klorgas är en akut toxisk gas som är svårhanterlig ur arbetsmiljösynpunkt. Resultaten av livscykelanalysen visar att desinfektion med UV-ljus och monokloramin är ca 45% mer energikrävande än de övriga alternativen. Den totala energianvändningen vid UVdesinfektion motsvarar ca 0,5-1% av den totala energin för att producera och distribuera dricksvatten. Vad gäller miljöpåverkan bidrar alternativet med UV-desinfektion med mest växthusemissioner. Emissioner bidragande till försurning och eutrofiering domineras av alternativet med hypokloritdesinfektion. För jämförelse av humantoxiska risker har två olika metoder använts. Enligt den ena metoden, USES-LCA, föreligger den största humantoxiska risken vid desinfektion med hypoklorit och klorgas. Enligt den andra, EDIP-metoden, föreligger de största riskerna vid desinfektion med hypoklorit samt med UV-ljus. De positiva följderna av en övergång till UV-desinfektion fås på bekostnad av en ökad energianvändning. Vilket alternativ som är att föredra avgörs av hur man lägger värderingen mellan de studerade delarna; energi- och miljöaspekter gentemot hälsoaspekter och arbetsmiljö. 2005-01-18 Other NonPeerReviewed application/pdf sv https://stud.epsilon.slu.se/12641/1/ekvall_c_171023.pdf Ekvall, Cecilia, 2004. LCA av dricksvattendesinfektion : en jämförelse av klor och UV-ljus. UNSPECIFIED, Uppsala. Uppsala: (NL, NJ) > Dept. of Biometry and Engineering <https://stud.epsilon.slu.se/view/divisions/HIST=3A120069.html> urn:nbn:se:slu:epsilon-s-8148 swe |
| spellingShingle | Water resources and management Faculty of Natural Resources and Agricultural Sciences (until 2013) Ekvall, Cecilia LCA av dricksvattendesinfektion |
| title | LCA av dricksvattendesinfektion |
| title_full | LCA av dricksvattendesinfektion |
| title_fullStr | LCA av dricksvattendesinfektion |
| title_full_unstemmed | LCA av dricksvattendesinfektion |
| title_short | LCA av dricksvattendesinfektion |
| title_sort | lca av dricksvattendesinfektion |
| topic | Water resources and management Faculty of Natural Resources and Agricultural Sciences (until 2013) |
| url | https://stud.epsilon.slu.se/12641/ https://stud.epsilon.slu.se/12641/ |