| 1. |
- Ahmad, Arslan
(författare)
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Evaluation and optimization of advanced oxidation coagulation filtration (AOCF) to produce drinking water with less than 1 μg/L of arsenic
- 2014
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Arsenic is an extremely poisonous element. It has been reported to cause contamination of drinking water sources in many parts of the world. The current drinking water permissible limit for arsenic in the European Union is 10 μg/L. The World Health Organization has a general rule that no substance may have a higher lifetime risk of more than 1 in 100,000. However, several studies on toxicity of arsenic suggest that purely based on health effects the arsenic limit of 10 μg/L is not sufficient. The main goal of this research was to develop an efficient arsenic removal technology that could be able to produce drinking water with an arsenic concentration of less than 1 μg/L. For this purpose, an innovative three step technique, Advanced Oxidation - Coagulation - Filtration (AOCF), was investigated through bench-scale and pilot scale experiments in the Netherlands at the water treatment plant of Dorst. Firstly, prior to the investigations on AOCF, the existing arsenic removal at the water treatment plant was investigated. Secondly, through a series of bench-scale experiments, the optimum type of coagulant, its combination dose with the selected chemical oxidant and optimum process pH were determined. Eventually, the partially optimized technique from the bench-scale was implemented at the pilot scale physical model of water treatment plant Dorst where AOCF was evaluated for arsenic removal and its effect on the removal of other common undesirable groundwater constituents. The optimized AOCF technology consistently removed arsenic from groundwater to below 1 ug/L when implemented at pilot scale. The overall effluent quality also remained acceptable. The method is efficient with both types of filtration media tested in this research i.e., virgin sand and metal oxide coated sand, however virgin sand media showed slightly better arsenic removal efficiency.
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| 2. |
- Balfors, Berit, et al.
(författare)
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Contamination of water resources in Takwa mining area of Ghana : Linking technical, social-economic and gender dimensions
- 2007
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Ghana is Africa’s second largest producer of gold with gold deposits in western part of the country. There are seven large-scale mines and 168 small-scale mining concessions valid in the region. Wassa West District is an important mining area, with Tarkwa as administrative capital. In recent years, the area has been exposed to lead, cadmium, arsenic, mercury and cyanide. Both small and large-scale mining industries have reportedly contaminated rivers, streams, dug wells and boreholes with heavy metals such as lead, cadmium, arsenic, mercury and cyanide. There has been significant adverse impact upon health, economy, and social life that may be felt differently by women and men, raising the question of sustainable access to safe water as a millennium development goal (MDG) in the area. A multi-disciplinary approach was adopted in the project with distinct work components on the technical as well as on social, gender and policy aspects. It also aimed to suggest integrated strategies to address the problem so as to ensure achievement of the MDGs. Based upon a field study in 37 local communities coupled with water and sediment analysis from the area, the research indicated the existence of not only higher levels of metal contaminants in local water resources in Tarkwa area, particularlymanganese and iron, but also arsenic and aluminium in some wells. However, water resources, particularly groundwater is currently safe for human consumption but the spillages of cyanide and other effluents into surface streams have health and ecological implications. Levels of mercury in stream sediments are high with a clear risk of methylation of the mercury and transfer in the food chain via fish to humans. Regarding the impact of mining, it was found that for women who are the primary domestic water managers, contamination of local water sources has forced them to fetch water from greater distances, and livelihoods are hampered due to the fish loss through cyanide spillages in streams. Another finding was the lack of trust and rising water conflicts between mining authorities and the local communities. Regarding the policy aspects underlying the problem, it was found that there is a lack of coordination between the 3 policy areas, namely, rural water supply, mining, and environmental impact assessment (EIA) and environmental protection to the detriment of women as water users and domestic water managers. While impact of mining is increasingly seen as an issue of human rights violation, little is being done to strengthen participatory approaches especially involving women in rural water supply programs. The detailed analysis of the EIA regulations reveals that most mining have not undertaken any comprehensive EIA guiding their operations. A number of recommendations have emerged from the integrated perspective attempted to be developed through this research. These include a need for further in-depth explorations on the situation of contamination in groundwater and surface waters as well as stream sediments in the area; the need to resolve the situations of water conflicts between the local communities and the mining authorities by promoting greater public participation; and the need to minimize the gaps between the three related policy frameworks. Also, there is a necessity to strengthen environmental compliance on part of the mining companies so as to uphold the quality of water resources in the area.
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| 3. |
- Bhattacharya, Prosun, 1962-, et al.
(författare)
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Arsenic in Groundwater of Bangladesh : Options for Safe Drinking Water
- 2010
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The study was undertaken in order to find and scientifically validate the options for arsenic safewater in Bangladesh. The study has been carried out in a geological province where most of theshallow wells have arsenic above the allowable limit for drinking water according to Bangladeshstandard. The original study plan has been modified as newer information on arsenic mobilisationand mitigation was available. Accordingly the emphasis on dug well and arsenic removal filter hadbeen shifted to other options such as geologically targeted aquifers. Also at the same time therehas been collaboration with number of other projects been carried out in and around the studyarea. Eventually the main focus of the research was shifted to capacity development in order toenhance the local capability for finding safer sources drinking water in the study area and othersimilar environments in the country.
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| 4. |
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| 5. |
- Elmi Mohamed, Abdullahi, 1965-
(författare)
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Sharing Water in Africa : Comparative Analysis of the Limpopo and Orange-Senqu River Basins in SADC and the Juba and Shabelle River Basins in the Horn of Africa
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- As water resources management becomes increasingly critical and many countries in the arid and semi-arid regions are increasingly forced to consider the possibilities of utilizing the water that is available in international rivers. Thus, the concerns relating to the use of international waters in shared rivers are becoming more important. The increasing competition over shared waters may have to lead either to more joint management and cooperation or to conflicts between basin countries.The purpose of the thesis work has been to analyze management of shared waters in international river basins with case studies from the Limpopo and the Orange River Basins in Southern African Development Community (SADC) region and the Juba and Shabelle River Basins in the Horn of Africa (HoA) region, focusing on river cooperation. The methodology employed was a comparative case study analysis through literature review, document analysis, interviews, focus groups and study visits.While similarities in climatic conditions and population growth stand out when comparing the basins in the two regions, the rivers differ primarily in terms of physical development of the water resources and institutional building for cross-border river cooperation. The Limpopo and Orange-Senqu river basins in the SADC region became reason for cooperation and catalyst of regional integration while the Juba and Shabelle river basins in the HoA has the potential to lead its riparian to conflict. The river basins in SADC established and operationalized functional system of river cooperation with both bilateral and multilateral basin-wide frameworks.The analysis concludes that management of water resources in internationally shared river basins is effectively affected by issues other than water. Sharing benefits from the shared waters in international rivers require basin-wide river cooperation. There are variety sets of factors that are of great importance for initiating, establishing and operationalizing river basin cooperation.
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| 6. |
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| 7. |
- Gut, Luiza, et al.
(författare)
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Oxygen Uptake Rate (OUR) tests for assessment of nitrifying activities in the deammonification system
- 2005
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The two-step deammonification system for nitrogen removal was established in a technical-scale pilot plant with moving-bed reactors with Kaldnes rings as biofilm carriers. The study consisted in observing the presence of nitrifiers in both activated sludge and biofilm in the partial nitritation reactor and in the Anammox reactor. Oxygen Uptake Rate (OUR) tests were used as a tool to assess qualitatively and quantitatively ammonia- and nitrite-oxidizing bacteria as well as heterotrophic activity. Thirteen series of OUR tests focussed on monitoring the activity of nitrifying microorganisms in the deammonification system. It was demonstrated that the nitrifying culture mostly forms biofilm in the partial nitritation reactor. The results confirmed that there is only insignificant nitrifying activity present in the Anammox reactor and it is mainly concentrated in the activated sludge. It is most likely that nitrifiers sustain oxygen-limited conditions for the Anammox bacteria. The moving-bed system is therefore appropriate to obtain efficient removal of nitrogen with taking advantage of the cooperation of many bacterial cultures.
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| 8. |
- Levlin, Erik, 1951-, et al.
(författare)
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Fosforåtervinning från avloppsrening med sidoströmshydrolys
- 2016
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Fosfor kan utvinnas från sidoströmshydrolys i reningsverk med biologisk fosforavskiljning. Lösligt fosfat frigörs vid hydrolys av returslam som är anaerob behandling där kolkälla framställs av slammet. Olika varianter för återvinnning från sidoström är t.ex. PhoStrip-processen, där fosfor utvinns från returslammet av fosforrikt slam från aktivslamprocesser med biologisk fosforreduktion. Ett annat alternativ är att återvinna fosfor från en sidoström som tas ut från den anaeroba delen av aktivslamprocessen, där fosfor har frigjorts till lösningen. Fosforåtervinning från fosforrik partiell sidoström beräknas ge en fosforåtervinning på 60-65%. Försök har utförts med slam från sidoströmshydrolys vid en process med biologisk fosforavskiljning. Efter separation av vattenfasen fälldes fosforn dels med magnesium och dels med kalcium vilket gav en utfällning av fosfor på 79 – 100 %. Vid fällning med magnesium bildades struvit (MgNH4PO4), och med kalcium kalciumfosfat (Ca10(OH)2(PO4)6). Analys av slam före (100 mg P/l) och efter slamhydrolysen visar att 20 % fosfor 20 mg P/l frigörs till vattenfasen. 124 ton fosfor i inkommande avlopp och 20 % frigöring av fosfor vid slamhydrolysen borde ge en fosforåtervinningspotential på 25 ton. Dock, med ett flöde av 54 m3/h genom slamhydrolysen blir fosforåtervinningspotential 9,5 ton per år.
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| 9. |
- Phumpiu, Patricia
(författare)
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The Politics of Honduras Water Institutional Reform
- 2008
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Rapport (populärvet., debatt m.m.)abstract
- The water and sanitation sector has been in the eye of the storm when referring to institutional reforms in Latin America. Concepts and methodologies have been imported from western countries and these have required adjustments of existing policies and the creation of a regulatory framework. Have these adjustments resulted in delivering an efficient implementation? What is the degree of dependence to the top-down approach, when the implementation stage comes into place?This study focuses first on understanding institutional and organisational structure in the Honduran water sector from 1990-2002. Second, the study analyses the changes generated by the institutional reform and evaluates the policy implementation of the institutional reform and their linkage with past performances and the traditional organisational structure from 2003-2006. Third, three exploratory case studies are presented as the outcomes of these institutional and organisational changes.Finally, the controversies of the institutional change are presented as dilemmas. They exposed the strengths, weaknesses and potentiality of the Water Institutional Reform (WIR). The result of the analysis is presented in the conclusions and indicates the weaknesses carried out from the traditional institutional and organisational water sector system. It proves as well that it is not only the rules that constraint the WIR process but the lack of creativity and incentives that individuals in charge -new administrators-, and not only the administration, thrust into the process.
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| 10. |
- Singh, Nandita, 1969-, et al.
(författare)
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Women and Water : Encountering the challenges of water resource management in rural India from gender perspective
- 2009
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Women are universally recognized as domestic water managers, concerned with both domestic water provision and use. This multi-facetted role of women, particularly in the rural setting, has been a cause of significant global concern, seen as constrained by factors like inaccessibility and non-reliability of water sources, arising primarily from problems with water quantity and quality. Assuming the universality of these constraints, the strategic water related need of women has been identified as having access to convenient, reliable and safe water sources located close to home. Such facilities are expected to contribute to their well-being and development through greater convenience, better health and enhanced socio-economic opportunities. The needs of rural women with respect to water have also been recognized in India through rural water supply programs. 88.4% rural habitations in India are fully covered with improved low-cost water supply sources that the users can help build and maintain themselves. For greater success and sustainability of the improved water sources, there has also been an emphasis on women's participation in operation and maintenance in particular and water management in general. However, observations in the so-called ‗covered' areas indicate that irrespective of the problem of water quality or quantity and the question of women's participation, inability on part of women to meet holistic and specific water needs of their families continues to persist, with continued dependence of many of them on traditional water sources that are distant and may not necessarily be safe. This research project was undertaken to decipher the realities underlying this paradox. Based upon a primary long-term field-based study following an interdisciplinary approach that blended socio-cultural dimensions with technical aspects of the problem, the research shows that the needs, interests & concerns of rural women with respect to improved water sources are diversified and so also their interest in participation and that all these are rooted in a complex web of 3 sets of micro-level factors embedded in the local socio-cultural matrix:(i) Cultural beliefs, values & norms defining standards of water quality that ultimately influence pattern of use of the new safe sources for the designated purpose of drinking & cooking; (ii) Social organizational principles, primarily caste, class, religion, as intersecting with gender, age & generation that influence the real access to improved water sources; and (iii) Divergence of the new technology from the traditional water technology & knowledge system that may thwart women's involvement in operation & maintenance, hence adversely affecting sustainability of the improved water sources - especially true in areas affected by high levels of arsenic and fluoride in drinking water where complex technologies for mitigation have been introduced. Also the new strategies introduced for promoting women's participation do not match the traditional gender norms. It was found that the development bureaucracies that design water supply programs are concerned with only the macro-level problems and their technological solutions, assuming that once provided, women will spontaneously adopt the improved sources and also participate actively in their upkeep and maintenance. They remain oblivious of the micro-level factors identified above that ultimately influence the use, access and sustainable management of water supply technologies, hence thwarting the benefits planned for women as water users and managers. The research recommends that water supply programs be re-conceptualized beyond a construct of mere technology, people (focus on women) and institutions. If real benefits are to be effectively delivered to the women for whom these are created, there is a need to integrate the socio-cultural context of implementation as the fourth aspect within the program design. Integration of this aspect will imply requisite changes in the program contents and strategies so as to make it more pragmatic, acceptable, workable and effective when introduced in local communities.
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| 11. |
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| 12. |
- Öberg, Ola, 1959-
(författare)
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ABBORÖS fas 1 : Odling av abborre i recirkulerande system i Östergötlands och Kalmars skärgårdar
- 2008
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Projekt ABBORÖS startade under hösten 2006. Syftet var att undersöka om det är möjligt att odla abborre i skärgården på ett sätt som klarar både miljömålen för verksamheter i Östersjön och de ekonomiska krav som ställs på en näringsverksamhet. Det nya med projektet är dels att abborre inte tidigare har odlats kommersiellt i Sverige och dels att odling av fisk i slutna system direkt i skärgårdshavet inte undersökts. Ytterligare en nyhet är att utnyttja kompetens hos yrkes-verksamma inom det kustnära fisket för utveckling av miljövänliga system för odling av fisk. AB-BORÖS är ett samarbete mellan institutionen för Mark- och vattenteknik vid KTH i Stockholm och åtta permanentboende i Östergötlands och Kalmars skärgårdar. Projektet som totalt omfattar en period av tre år är uppdelat i två faser. Den första fasen med en budget på 12 miljoner löpte från oktober 2006 till februari 2008. Den andra fasen löper från juni 2008 till juni 2010 med en budget på 22 miljoner. Under projektets gång sysselsätts ett 10-tal personer och på sikt förväntas projektet bidraga med 15-20 arbetstillfällen i skärgården. Under fas 1 av projektet har kunskap om odlingsteknik och yngelproduktion byggts upp med hjälp av ett nätverk av svenska och inter-nationella experter. Projektets deltagare har ökat sin kompetens och sin förmåga att samarbeta. De har också installerat en basstruktur för sex odlingsenheter och odlingsutrustning till 15 % av den tilltänkta storleken vid projektets slut. Detta innebär att de står väl rustade för att i fas 2 kun-na utföra försök i full skala. Efter första året finns ungefär 200 000 abborrar fördelade i de sex odlingsenheterna. De första abborrarna förväntas ha uppnått full storlek tre somrar efter kläck-ning, vilket innebär hösten 2008. För institutionen Mark- och vattenteknik och andra intresserade forskargrupperingar innebär engagemang i projektet att ett fältlaboratorium med teknisk personal finns tillgängligt för försök och forskning om fiskodling och miljöteknik.
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