| 1. |
- Jonsson, Sofia, 1973-, et al.
(författare)
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Comparison of Fenton's Reagent and Ozone Oxidation of Polycyclic Aromatic Hydrocarbons in Aged Contaminated Soils
- 2006
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Ingår i: Journal of Soils and Sediments. - Berlin : Springer. - 1614-7480 .- 1439-0108. ; 6:4, s. 208-214
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Tidskriftsartikel (refereegranskat)abstract
- Background, Aim and Scope: Polycyclic aromatic hydrocarbons (PAHs) are formed as a result of incomplete combustion and are among the most frequently occurring contaminants in soils and sediments. PAHs are of great environmental concern due to their ubiquitous nature and toxicological properties. Consequently, extensive research has been conducted into the development of methods to remediate soils contaminated with PAHs. Fenton's reagent or ozone is the most commonly studied chemical oxidation methods. However, the majority of remediation studies use soils that have been artificially contaminated with either one or a limited number of PAH compounds in the laboratory. Hence, it is essential to extend such studies to soils contaminated with multiple PAHs under field conditions. Objectives. The objective of this study is to investigate the capacity of Fenton's reagent and ozone to degrade PAHs in soils. The soils have been collected from a number of different industrial sites and, therefore, will have been exposed to different PAH compounds in varying concentrations over a range of time periods. The capacity of Fenton's reagent and ozone to degrade PAHs in industrially contaminated soils is compared to results obtained in studies using soils artificially contaminated with PAHs in the laboratory. Materials and Methods: Nine soil samples, contaminated with PAHs, were collected from five different industrial sites in Sweden. For the Fenton's reagent procedure, the pH of the soil slurry samples was adjusted to pH 3 and they were kept at a constant temperature of 70ºC whilst H2O2 was added. For the ozone procedure, soil samples were mixed with 50% water and 50% ethanol and kept at a constant temperature of 45 ºC. Ozone was then continually introduced to each soil sample over a period of four hours. Following the Fenton's reagent and ozone oxidation procedures, the samples were filtered to isolate the solid phase, which was then extracted using pressurized liquid extraction (PLE). The sample extracts were cleaned up using open columns and then analysed by gas chromatography-mass spectrometry (GC-MS). Results: The relative abundance of the detected PAHs varied between soils, associated with different industries. For example, low molecular weight (LMW) PAHs were more abundant in soil samples collected from wood impregnation sites and high overall PAH degradation efficiencies were observed in soils originating from these sites. In the contaminated soils studied, PAHs were more effectively degraded using Fenton's reagent (PAH degradation efficiency of 40-86%) as opposed to ozone (PAH degradation efficiency of 10-70%). LMW PAHs were more efficiently degraded, using ozone as the oxidizing agent, whereas the use of Fenton's reagent resulted in a more even degradation pattern for PAHs with two through six fused aromatic rings. Discussion: The degradation efficiency for both methods was largely dependent on the initial PAH concentration in the soil sample, with higher degradation observed in highly polluted soils. LMW PAHs are more susceptible to degradation than high molecular weight (HMW) PAHs. As a result of this the relative abundance of large (often carcinogenic) PAHs increased after chemical oxidation treatment, particularly after ozone treatment. Repeated Fenton's reagent treatment did not result in any further degradation of soil PAHs, indicating that residual soil PAHs are strongly sorbed. The effectiveness of the two oxidation treatment approaches differed between industrial sites, thus highlighting the importance of further research into the influence of soil properties on the sorption capacity of PAHs. Conclusions: This study demonstrates that the degree to which chemical oxidation techniques can degrade soil bound PAHs chemical degradation is highly dependent on both the concentration of PAHs in the soils and the compounds present, i.e. the various PAH profiles. Therefore, similarities in the PAH degradation efficiencies in the nine soil samples studied were observed with the two chemical oxidation methods used. However, the degradation performance of Fenton's reagent and ozone differed between the two methods. Overall, Fenton's reagent achieved the highest total PAH degradation due to stronger oxidation conditions. LMW PAHs showed higher susceptibility to oxidation, whereas high molecular weight (HMW) PAHs appear to be strongly sorbed to the soils and therefore less chemically available for oxidation. This study highlights the importance of including soils collected from a range of contaminated sites in remediation studies. Such soil samples will contain PAH contaminants of varying concentrations, chemical and physical properties, and have been aged under field conditions. In addition to the chemical and physical properties of the soils, these factors will all influence the chemical availability of PAHs to oxidation. Recommendations and Perspectives: We recommend including aged contaminated soils in chemical degradation studies. In future chemical remediation work, we intend to investigate the potential influence of the chemical and physical properties of PAHs and soil parameters potential influence on the chemical oxidation efficiency in aged contaminated soils. Due to the vast number of contaminated sites there is a great need of efficient remediation methods throughout the world. This study shows the difficulties which may be experienced when applying remediation methods to a variation of contaminated sites.
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| 2. |
- Jonsson, Sofia, 1973-, et al.
(författare)
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Degradation of polycyclic aromatic hydrocarbons (PAHs) in contaminated soils by Fenton's reagent : a multivariate evaluation of the importance of soil characteristics and PAH properties
- 2007
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 149:1, s. 86-96
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Tidskriftsartikel (refereegranskat)abstract
- In this study, we investigated how the chemical degradability of polycyclic aromatic hydrocarbons (PAHs) in aged soil samples from various contaminated sites is influenced by soil characteristics and by PAH physico-chemical properties. The results were evaluated using the multivariate statistical tool, partial least squares projections to latent structures (PLS). The PAH-contaminated soil samples were characterised (by pH, conductivity, organic matter content, oxide content, particle size, specific surface area, and the time elapsed since the contamination events, i.e. age), and subjected to relatively mild, slurry-phase Fenton's reaction conditions. In general, low molecular weight PAHs were degraded to a greater extent than large, highly hydrophobic variants. Anthracene, benzo(a)pyrene, and pyrene were more susceptible to degradation than other, structurally similar, PAHs; an effect attributed to the known susceptibility of these compounds to reactions with hydroxyl radicals. The presence of organic matter and the specific surface area of the soil were clearly negatively correlated with the degradation of bi- and tri-cyclic PAHs, whereas the amount of degraded organic matter correlated positively with the degradation of PAHs with five or six fused rings. This was explained by enhanced availability of the larger PAHs, which were released from the organic matter as it degraded. Our study shows that sorption of PAHs is influenced by a combination of soil characteristics and physico-chemical properties of individual PAHs. Multivariate statistical tools have great potential for assessing the relative importance of these parameters.
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| 3. |
- Andersson-Sköld, Yvonne, et al.
(författare)
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An integrated method for assessing climate-related risks and adaptation alternatives in urban areas
- 2015
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Ingår i: Climate Risk Management. - : Elsevier BV. - 2212-0963. ; 7, s. 31-50
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Tidskriftsartikel (refereegranskat)abstract
- © 2015 The Authors. The urban environment is a complex structure with interlinked social, ecological and technical structures. Global warming is expected to have a broad variety of impacts, which will add to the complexity. Climate changes will force adaptation, to reduce climate-related risks. Adaptation measures can address one aspect at the time, or aim for a holistic approach to avoid maladaptation. This paper presents a systematic, integrated approach for assessing alternatives for reducing the risks of heat waves, flooding and air pollution in urban settings, with the aim of reducing the risk of maladaptation. The study includes strategies covering different spatial scales, and both the current climate situation and the climate predicted under climate change scenarios. The adaptation strategies investigated included increasing vegetation; selecting density, height and colour of buildings; and retreat or resist (defend) against sea-level rise. Their effectiveness was assessed with regard to not only flooding, heat stress and air quality but also with regard to resource use, emissions to air (incl. GHG), soil and water, and people's perceptions and vulnerability. The effectiveness of the strategies were ranked on a common scale (from -3 to 3) in an integrated assessment. Integrated assessments are recommended, as they help identify the most sustainable solutions, but to reduce the risk of maladaptation they require experts from a variety of disciplines. The most generally applicable recommendation, derived from the integrated assessment here, taking into account both expertise from different municipal departments, literature surveys, life cycle assessments and publics perceptions, is to increase the urban greenery, as it contributes to several positive aspects such as heat stress mitigation, air quality improvement, effective storm-water and flood-risk management, and it has several positive social impacts. The most favourable alternative was compact, mid-rise, light coloured building design with large parks/green areas and trees near buildings.
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| 4. |
- Eriksson, Charli, 1948-, et al.
(författare)
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NCFF - Nationellt centrum för främjande av en god hälsa hos barn och ungdom : en sjuårig historia
- 2012
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Ingår i: Folkhälsostämman 2012. - Stockholm : Statens folkhälsoinstitut. - 9789175210117 ; , s. 85-85
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Bakgrund och syfte: Nationellt centrum för främjande av god hälsa hos barn och ungdom (NCFF) bildades våren 2004 på uppdrag av Utbildningsdepartementet. Huvudfokus var fysisk aktivitet men 2006 gavs ett utökat uppdrag att även arbeta för goda matvanor och andra hälsoframjande verksamheter hos barn och ungdom. Sedan dess har NCFF, utifrån skolans övergripande mål och riktlinjer, stöttat skolor genom att: 1) sprida erfarenheter och goda exempel, 2) stödja och informera om forskning och utvecklingsprojekt, 3) verka for en ökad samverkan mellan universitet och högskolor, kommuner, andra skolhuvudmän och myndigheter, intresseorganisationer samt regionala och lokala organisationer, samt 4) verka for en helhetssyn på sambandet mellan god hälsa och barn och ungdomars lärande/utveckling.Metod/idébeskrivning: Verksamheten kan beskrivas utifran fyra målområden:• Strategisk inriktning: Främja god hälsa, goda levnadsvanor, lärande och utveckling. Ett hälsoframjande perspektiv som präglar hela skolverksamheten.• Kunskapsförmedling – utbildning: Fortbildning (konferenser, utbildningsinsatser), kommunikativa insatser (nyhetsbrev, hemsida, sociala medier), och produktion av material.• Kunskapsuppbyggnad – forskning och utveckling: Vetenskapligt råd, nationella utvärderingar, kunskapsöversikter, och samverkan med forskare.• Samverkan och innovation: NCFF verkar genom och tillsammans med andra, nätverkar och samarbetar med lokala, nationella och internationella aktörer.Resultat /lägesrapport: Verksamheten bidrar till att ord omsätts i handling och att handling omsatts i ord. Samarbetet med andra parter betyder resultat fastän en begränsad budget. Sedan 2004 har 3 500 skolor deltagit i NCFFs arrangemang vilket motsvarar hälften av landets grund- och gymnasieskolor.Diskussion/uppföljning: Hälsoarbetet i skolan handlar om att skapa goda lärmiljöer där elever trivs och mår bra – en angelägenhet som beror hela skolan. Betydelsefullt ar att stödja, inspirera och starka kunskapsutvecklingen om sambandet mellan lärande och hälsa. En framtida viktig målgrupp ar elevhälsan i och med dess nya roll att arbeta mer stödjande, forebyggande och hälsofrämjande.
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| 5. |
- Jonsson, Martin, 1973-, et al.
(författare)
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Lärande genom designutforskande : En pedagogisk ansats för samverkan och social innovation inom högre utbildning
- 2020
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Ingår i: NU2020. - Södertörns högskola.
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Konferensbidrag (refereegranskat)abstract
- Problembaserat lärande (PBL) är en vanlig undervisningsform inom såväl grundskola som högre utbildning. Inom PBL arbetar studenterna självständigt och lösningsorienterat med problem eller utmaningar som utgångspunkt. Denna undervisningsform lämpar sig därför bra för å ena sidan samverkansprojekt där man arbetar med externa utmaningar, och å andra sidan för att utforska samhällsutmaningar där fokus ofta ligger på hållbarhet eller socialt ansvarstagande. Trots att PBL är en väletablerad undervisningsform, kan den ibland upplevas som trubbig och underutvecklad från ett pedagogiskt perspektiv. Inom vår utbildningspraktik har vi under många år arbetat med utbildningar i designmetodik, designtänkande och innovationspraktiker. I det arbetet har vi identifierat möjligheter att generalisera och överföra delar av dessa praktiker till andra domäner där man arbetar med PBL, samverkan och samhällsutmaningar. Ett intressant exempel är masterkursen “Challenges for Emerging Cities: Open Lab Multidisciplinary Project Course”, där studenter från en mängd olika discipliner från fyra olika universitet och högskolor använder designmetoder för att beforska och hitta kreativa lösningar på samhällsproblem formulerade av externa uppdragsgivare. Som en del i arbetet med att utveckla dessa lärandeformer har vi tagit fram en pedagogisk modell - Lärande genom designutforskande (Design Inquiry Learning), där vi strävar efter att vidareutveckla befintliga problembaserade ansatser genom att arbeta fram en form av utforskningsbaserat lärande baserat på processorienterat och kreativt designutforskande. Central för modellen är designtänkande-metodik (Design Thinking), där ett kreativt förhållningssätt och problemlösningsmetoder inspirerade av professionella designers verksamhet används för att hitta lösningar på komplexa problem och samhällsutmaningar. Denna metod är speciellt lämplig för att ifrågasätta konventionella tankesätt, se nya möjligheter i strategiska sammanhang och att fokusera på att identifiera intressanta och hanterbara problem i ett större problemkomplex. Designers utgår som regel från ett användarperspektiv och experimenterar sig fram till insikter och lösningar med hjälp av praktiska metoder och verktyg för datainsamling, visualisering, idégenerering, testning och beslutsfattande. Våra erfarenheter från ett flertal kurser på både grund-, avancerad-, och doktorandnivå visar att studenter som jobbar med denna typ av metoder snabbt skapar djup förståelse för och insikter inom komplexa problemområden, samt att metoderna ger stöd och struktur, inte bara för det praktiska arbetet utan även för lärprocesserna. Denna typ av arbetsformer ger även ett bra gränssnitt gentemot externa uppdragsgivare, med tydliga former för erfarenhetsutbyten och återrapportering. Ofta när designmetodik och designtänkande diskuteras inom utbildning, ligger fokus på förmåga till innovation och kreativa lösningar. En viktig poäng vi vill göra här är dock att sådana processer också kan fungera som medel till förståelse och kunskap om de problemdomäner som utforskas.
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| 6. |
- Jonsson, Sofia, 1973-, et al.
(författare)
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Dioxin removal from contaminated soils by ethanol washing
- 2010
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Ingår i: Journal of Hazardous Materials. - : Elsevier. - 0304-3894 .- 1873-3336. ; 179:1-3, s. 393-399
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to investigate the potential utility of ethanol washing for remediating soils contaminated with polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), as a cost-efficient alternative to conventional remediation methods of PCDD/F-contaminated soils. Initially, screening experiments were performed with a two-level full factorial design to examine the effects of temperature, extraction time and ethanol concentration on the removal efficiency. The screening experiments showed that the ethanol concentration was the most important parameter. In addition, repeated washing cycles considerably improved the results. Ethanol washing conditions were then selected (10 wash cycles with 75% ethanol at 60 °C), and applied to four soils with different soil characteristics and contamination levels to test the robustness of the selected method. Treatment efficiencies of 81% and 85% were obtained for a lightly contaminated sandy–silty soil and a highly contaminated clay soil rich in graphite particles, respectively. Even higher treatment efficiencies (≥97%) were obtained for two other highly contaminated soils, one of which contained high amounts of organic matter. PCDD/Fs were found to both dissolve in the solvent and migrate into it as species adsorbed to particles. The relative contributions of these mechanisms and the overall efficiency of the removal seem to depend on contaminant concentration, the types of carbon in the soil matrix and the particle size distribution. The study shows that ethanol washing has effective remediation potential for a variety of PCDD/F-contaminated soils.
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| 7. |
- Jonsson, Sofia, 1973-, et al.
(författare)
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Granular activated carbon (GAC)- extraction of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans from soil washing liquids of contaminated soils
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Ethanol washing has been recently shown to be a potentially useful technique for remediating soils contaminated with polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). During this process, the contaminants are transferred from the soils to the washing liquid, producing a highly toxic extract. Consequently, there is a need for a post-treatment technique that removes the PCDD/F from the washing liquid, enabling its recirculation. In this study, the potential utility of granular activated carbon (GAC) as an adsorbent for extracting PCDD/Fs from soil-washing liquids was investigated. The washing liquids were produced by extraction of two former sawmill sites, at which chlorophenol based preservatives had been used. The PCDD/F levels in the washing liquids were 42 and 540 pg TEQ PCDD/F /g soil, and the organic contents in the soils differed greatly prior to the washing procedure. Ten 80 mL aliquots of the extracts of each soil, each corresponding to approximately 25 g of soil, were treated with 0-1.5 g GAC to adsorb the contaminants. In both cases, a removal efficiency of 96% was attained, but 15-fold more GAC was needed to clean the liquid used to treat the soil with the high organic content to this degree (1.5 g versus 0.1 g for the liquid used to wash the other soil). Hence, the extraction efficiency of the GAC treatment appears to be influenced by the amount of organic matter in the soil, probably due to competition between PCDD/F and other organic compounds (natural organic matter and other contaminants) in the soil for the GAC adsorption sites, since GAC adsorbs non-specifically. The results in this study provide promising indications that GAC can be used to remove dioxins from soil-washing liquid, thereby facilitating recirculation and reducing treatment costs. We also propose a number of additional procedures that may be needed for a complete soil-solvent washing process.
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| 8. |
- Jonsson, Sofia, 1973-
(författare)
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The influence of soil and contaminant properties on the efficiency of physical and chemical soil remediation methods
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A vast number of sites that have been contaminated by industrial activities have been identified worldwide. Many such sites now pose serious risks to humans and the environment. Given the large number of contaminated sites there is a great need for efficient, cost-effective remediation methods. Extensive research has therefore been focused on the development of such methods. However, the remediation of old industrial sites is challenging, for several reasons. One major problem is that organic contaminants become increasingly strongly sequestered as they persist in the soil matrix for a long period of time. This process is often referred to as ‘aging’, and leads to decreasing availability of the contaminants, which also affects the remediation efficiency. In the work underlying this thesis, the influence of soil and contaminant properties on the efficiency of various physical and chemical soil remediation methods was investigated. The investigated contaminants were polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). Briefly, the results show that as the size of soil particles decreases the contaminants become more strongly sorbed to the soil’s matrix, probably due to the accompanying increases in specific surface area. This affected the efficiency of the removal of organic pollutants by both a process based on solvent washing and processes based on chemical oxidation. The sorption strength is also affected by the hydrophobicity of the contaminants. However, for a number of the investigated PAHs their chemical reactivity was found to be of greater importance for the degradation efficiency. Further, the organic content of a soil is often regarded as the most important soil parameter for adsorption of hydrophobic compounds. In these studies the effect of this parameter was found to be particularly pronounced for the oxidation of low molecular weight PAHs, but larger PAHs were strongly adsorbed even at low levels of organic matter. However, for these PAHs the degradation efficiency was positively correlated to the amount of degraded organic matter, probably due to the organic matter being oxidized to smaller and less hydrophobic forms. The amount of organic matter in the soil had little effect on the removal efficiency obtained by the solvent-washing process. However, it had strong influence on the performance of a subsequent, granular activated carbon-based post-treatment of the washing liquid. In conclusion, the results in this thesis show that remediation of contaminated soils is a complex process, the efficiency of which will be affected by the soil matrix as well as the properties of the contaminants present at the site. However, by acquiring thorough knowledge of the parameters affecting the treatability of a soil it is possible to select appropriate remediation methods, and optimize them in terms of both remediation efficiency and costs for site- and contaminant-specific applications.
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| 9. |
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| 10. |
- Lundmark, Sofia, PhD, et al.
(författare)
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Becoming a Designer at the Design Lab : Empowerment and participation in children's design activities
- 2021
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Ingår i: C&C ’21. - New York : Association for Computing Machinery (ACM). - 9781450383769
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Konferensbidrag (refereegranskat)abstract
- This paper draws on data from an interview study with children engaged in a leisure time design lab situated in a socioeconomically vulnerable neighborhood. The study accounts for how the children involved in the design activities make sense of their experiences of participating in the design lab. Some perspectives on the relationship between design and empowerment are discussed and three empowering functions of the activities are identified that serve to empower the children in different ways: 1) The creative laboratory-How the activities allow for exploration and experimentation of both new identities and of new possible futures. 2) Community participation-How the design lab enables participation in the local community and reflections on what it means to be a citizen. 3) Playful apprenticeship-How the lab builds a peer-culture where children are continuously addressed and presented as equal colleagues in the lab, both in internal and external settings.
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