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  • 1.
    Forss, Jörgen
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Lindh, Markus V.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Pinhassi, Jarone
    Linnaeus University, Faculty of Science and Engineering, School of Engineering. Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Welander, Ulrika
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Biotreatment of actual textile wastewater in a continuous biofilter and the associated bacterial and fungal microflora.Manuscript (preprint) (Other academic)
    Abstract [en]

    Textile processes use many different chemicals, most of which ends up in wastewater. Coloring of clothes is a particularly troublesome process since both azo and anthraquinone dyes are recalcitrant to degradation, causing environmental concerns. Hence, there is a great need to investigate and develop safe and applicable systems to the water demanding industry, such as textile mills in developing countries.

    In the present study biodegradation of actual textile wastewater (containing azo and anthraquinone dyes) was evaluated in biofilters. Indigenous decolourants from rice husks were used in bioreactors and the degradation was analyzed with spectrophotometer and liquid chromatography coupled with mass spectrometry (LC/MS/MS) to monitor metabolites, especially in the form of aromatic amines. Chemical characteristics of the water were and bacterial and fungal community composition was monitored by denaturing gradient gel glectrophoresis (DGGE) analysis and subsequent sequencing of the 16S rRNA and ITS gene fragments.

    The indigenous microflora consistently performed over 90% decolorization at a hydraulic retention time of 67 h. The molecular fingerprinting revealed the presence of bacteria such as Clostridium, Pseudomonadales, Xenophilus, Paenibacillus, Acinetobacter and Sphingomonas, all known to carry genes for azoreductases.  Furthermore, results showed that fungi were present in the biofilter, and were predominant in the aerobic reactors.

    Collectively, these results indicate that the developed biofilter with rice husks support a mixed microbial community of both bacteria and fungi, with key features contributing to an efficient and reliable degradation performance of actual textile wastewater.

  • 2.
    Forss, Jörgen
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Lindh, Markus V.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Pinhassi, Jarone
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Welander, Ulrika
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Microbial biotreatment of actual textile wastewater in a continuous sequential rice husk biofilter and the microbial community involved2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 1, article id e0170562Article in journal (Refereed)
    Abstract [en]

    Textile dying processes often pollute wastewater with recalcitrant azo and anthraquinone dyes. Yet, there is little development of effective and affordable degradation systems for textile wastewater applicable in countries where water technologies remain poor. We determined biodegradation of actual textile wastewater in biofilters containing rice husks by spectrophotometry and liquid chromatography mass spectrometry. The indigenous microflora from the rice husks consistently performed >90% decolorization at a hydraulic retention time of 67 h. Analysis of microbial community composition of bacterial 16S rRNA genes and fungal internal transcribed spacer (ITS) gene fragments in the biofilters revealed a bacterial consortium known to carry azoreductase genes, such as Dysgonomonas, and Pseudomonas and the presence of fungal phylotypes such as Gibberella and Fusarium. Our findings emphasize that rice husk biofilters support a microbial community of both bacteria and fungi with key features for biodegradation of actual textile wastewater. These results suggest that microbial processes can substantially contribute to efficient and reliable degradation of actual textile wastewater. Thus, development of biodegradation systems holds promise for application of affordable wastewater treatment in polluted environments.

  • 3.
    Forss, Jörgen
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Pinhassi, Jarone
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Lindh, Markus V.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Welander, Ulrika
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Microbial diversity in a continuous system based on rice husks for biodegradation of the azo dyes Reactive Red 2 and Reactive Black 52013In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 130, p. 681-688Article in journal (Refereed)
    Abstract [en]

    In the present study the degradation of two common azo dyes used in dye houses today, Reactive Black 5 and Reactive Red 2 was evaluated in biofilters. In two experiments, bioreactors performed over 80% decolorization at a hydraulic retention time of only 28.4 h with little production of metabolites. Molecular analyses showed a diverse and dynamic bacterial community composition in the bioreactors, including members of the Bacteroidetes, Acinetobacter (Gammaproteobacteria) and Clostridium (Firmicutes) that possess the capacity to reduce azo dyes. Collectively, the results indicate that the development of mixed bacterial communities from natural biomaterials contributes to an efficient and robust degradation performance in bioreactors even at high concentration of dyes.

  • 4.
    Forss, Jörgen
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Welander, Ulrika
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Biodegradation of azo and anthraquinone dyes in continuous systems2011In: International Biodeterioration & Biodegradation, ISSN 0964-8305, E-ISSN 1879-0208, Vol. 65, no 1, p. 227-237Article in journal (Refereed)
    Abstract [en]

    The purpose is to develop a complete microbiological model system for the treatment of wastewater

    from textile mills in developing countries. Arti

    fi

    cial wastewater was treated by microorganisms growing

    on wood shavings from Norway spruce during unsterile conditions. The microorganisms were inoculated

    from forest residues. Mixtures of the azo dyes Reactive Black 5 and Reactive Red 2 were degraded in

    batch as well as continuous experiments. Reactive Red 2 mixed with the anthraquinone dye Reactive

    Blue 4 was also treated in the continuous system. The system consisted of three reservoirs

     

     

    e the fi

    rst two

    with an anaerobic environment and the third with an aerobic. The dye concentrations were 200 mg l

     

     

    1

    of

    each dye in the continuous system and the retention time was approximately 4 days and 20 h per

    reservoir. Samples from the process were analysed with spectrophotometer and LC/MS to monitor the

    degradation process. 86-90% of the colour was removed after a treatment of 4 days and 23 h in the

    continuous process. Two metabolites were found in the outlets of reactors one and two, but they were

    degraded to below the detection limit in the aerobic reactor.

     

     

     

  • 5.
    Forss, Jörgen
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Avdelningen för Bioenergiteknik.
    Welander, Ulrika
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Avdelningen för Bioenergiteknik.
    Biodegradation of azo dyes by natural microflora from forest residues chips cultivated on Swedish soft wood chips2008In: 16th European Biomass Conference& Exhibition, 2-6 June 2008, Valencia,Spain, ETA-Forence renewable energies , 2008Conference paper (Refereed)
    Abstract [en]

    By use of wood chips as a carrier and coal donator, azo dyes are biodegraded by the native microflora inhabiting forest residues chips from the south east part of Sweden. Due to background emissions from the forest residues chips the microflora are successfully transferred to soft sood chips from Norwegian spruce (picea abis) and Scots pine (pinus sylvestris). The azo dyes used in this study are reactive red 2 and reactive black 5 in combined artifical wastewater. The dyes are at a concentration of 200 mg/l degraded within 20 days with additional yeast extract of 1 g/l and 30 days without.

  • 6.
    Forss, Jörgen
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Welander, Ulrika
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Biodegradation of Textile Dyes Based on Wood Carriers2010In: Proceedings of Linnaeus SCO-TecH'10 / [ed] Fabio Kaczala, Sandrine Arzur, Ida Tjäder, William Hogland, Linnaeus University , 2010, p. 267-277Conference paper (Other academic)
    Abstract [en]

    Biodegradation of textile dyes from the azo class by Bjerkandera sp.and microbial consortium from forest residues. Bjerkandera’s degradation ability was evaluated in unsterile environment and put out of competition from the microbial consortium inhabiting forest residues. Microorganisms from forest residues were evaluated and transferred to soft wood shavings with maintained biodegrade performance. A continuous system was created containing anaerobic and aerobic parts and a successful degradation was monitored by spectrophotometer and High pressure liquid chromatography (HPLC).

  • 7.
    Gregeby, Erik
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Welander, Ulrika
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Provrötning av marina substrat i laboratorie- och pilotskala: Delstudie i projektet Biogas – Nya substrat från havet2012Report (Other academic)
    Abstract [sv]

    Denna rapport omfattar delstudie 4 av projektet Biogas-Nya substrat från havet. Inom delstudien har ett antal provrötningar av substrat från havet (vass, musslor, alger och skrapsill) genomförts. Syftet med delstudien var att få fram metanpotentialen för de olika substraten och att öka kunskapen kring hur dessa substrat uppför sig i en biogasprocess. Projektet var ett samverkansprojekt delfinansierat av EU Regionala fonden för Småland och öarna. Projektledare var Regionförbundet i Kalmar län. Inledningsvis genomfördes ett antal satsvisa försök med samtliga substrat. Metanpotentialerna för vassen, musslorna, algerna respektive skarpsillen var 400, 270, ca 210 och 460 Ndm3/kg VS. Ymp hämtades från Kalmar Biogas ABs industriella rötkammare. Vassen samrötades också med industriellt avfall i ett kontinuerligt våtrötningsförsök. Försöket genomfördes i två total omrörda tankreaktorer med volymen 30 l/st. Tillsatsen av vass gav en utökad metanproduktion med 220 Ndm3/kgVS.

    Vassen och musslorna studerades också i torrötningsförsök. Försöken i laboratorieskala genomfördes vid Avdelningen för Bioteknik i Lund medan försöket med musslor i pilotskala genomfördes vid Avdelningen för Bioenergiteknik, Linnéuniversitet. Metanpotentialen för vassen var i torrötningsförsöket ca 220 Ndm3/kg VS vilket är lika med potentialen i våtrötningsförsöket. För musslorna erhölls en metanpotential på 330 Ndm3/kg VS i laboratorieskaleförsöket. Pilotskaleförsöket visade att hydrolysen etablerades på likartat sätt som i laboratorieskaleförsöket. Metanhalten var ca 70 %. En visuell inspektion av musslorna efter rötningen visade också att endast skalen återstod. Det är dock inte möjligt att ange en metanpotential från detta försök beroende på ett antal tekniska problem med processen. Processen byggdes inför detta försök och det fanns inte tid att testköra den samma före försökets start.Arbetet med de satsvisa försöken och det kontinuerliga våtrötningsförsöket av vass genomfördes i samarbete med Kalmar Biogas AB. Detta bland annat genom att Kalmar Biogas AB tillhandahöll sin försöksanläggning med satsvisa och kontinuerliga reaktorer till projektet.

  • 8.
    Gregeby, Erik
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Welander, Ulrika
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    The influence of mixing, addition of buffer, silage and chicken manure on the biogas production from cattle manure2010In: 18th European Biomass Conference and Exhibition, 3-7 May, Lyon, ETA Renewable Energies and WIP Renewable Energies , 2010Conference paper (Refereed)
    Abstract [en]

    A number of batch experiements were performed in order to evaluate the biogas production from cattle manure adter addition of buffer, silage or chicken manure. Some experiments were also performed to investigate the effect of mixing. All experiments were performed at 35 C. The results showed that the extent of mixing did not affect the biogas production to any larger extent. The addition of buffer speeds up the start of the process and increased the volume of biogas produced. The methane content was approximately the same independently on if a buffer was added or not. Chicken manure inhibited the process adn addition of silage gave an increase in the amount of biogas produced. No significant effect of silage addition was found on the methane content of the biogas.

  • 9. Håkansson, Katarina
    et al.
    Welander, Ulrika
    Mattiasson, Bo
    Degradation of acetonitrile through a sequence of microbial processes2005In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, p. 648-654-Article in journal (Refereed)
    Abstract [en]

    Degradation of nitrogen containing organic compounds often leads to formation of ammonium and low molecular weight organic compounds. The study is focuseed on degradtion of acetonitrile in a sequence of stirred biofilm reactors, where degradation of acetonitrile to acetic acid and ammonia takes place in the first two reactors. A large fraction of the acetic acid is also degraded in these reactors. The subsequent two reactors were introduced in order to take care of the ammonia, while a fifth reactor was a polishing step before the water was released to the recipient. From earlier studies it is known that the rate of acetonitrile degradation is approximately 80 g acetonitrile/(m3 reactor h). This means that the reactors involved in remval of the nitrogen component needs to be far larger than those dealing with degradation of the more complex molecules.

  • 10.
    Jansson, Anette
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Rupar-Gadd, Katarina
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Forss, Jörgen
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Welander, Ulrika
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Pilot-Scale Experiments Using Cultivated Macro Algae for Biogas Production, Part of a Future Seafarm Biorefinery2016In: 24th EUBCE Online Proceedings 2016: Setting the course for a biobased economy. Held in Amsterdam, The Netherlands, 6 - 9 June 2016, ETA-Florence Renewable Energies , 2016, p. 627-629Conference paper (Refereed)
    Abstract [en]

    The research is focused on evaluation of substrates not commonly used for biogas production and the development and optimization of processes adjusted to these substrates. This study deals with evaluation of sea weeds (Saccharina Lattisima and Laminaria digitata). Biomethane potential tests (BMP) have shown the methane potential of the algae to be 180-440 l CH4/kg organic material. These potentials are in the same range as potentials found for commonly used substrates such as sewage sludge and slaughterhouse waste. Sampling of produced biogas, substrate and digest were performed by using Solid Phase Microextraction (SPME) followed by analysis by a Gas Chromatograph with a Mass Spectrometrer (GC-MS) in order to develop a method to be able to characterize, monitor and possibly control the process.

  • 11. Mattiasson, Bo
    et al.
    Welander, Ulrika
    Denitrification at low temperatures using a suspended carrier biofilm process2003In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 37, p. 2394-2398Article in journal (Refereed)
  • 12. Möller, Anna
    et al.
    Grahn, Anna
    Welander, Ulrika
    Precipitation of heavy metals from landfill leachates by microbially produced sulphide2004In: Environmental technology, ISSN 0959-3330, E-ISSN 1479-487X, Vol. 25, p. 69-77Article in journal (Refereed)
  • 13.
    Nordström, F
    et al.
    Center for Chemistry and Chemical Engineering, Department of Biotechnology, Lund University, Lund, Sweden.
    Terrazas, E
    Center for Chemistry and Chemical Engineering, Department of Biotechnology, Lund University, Lund, Sweden.
    Welander, Ulrika
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Center for Chemistry and Chemical Engineering, Department of Biotechnology, Lund University, Lund, Sweden.
    Decolorization of a mixture of textile dyes using Bjerkandera sp. BOL 132008In: Environmental technology, ISSN 0959-3330, E-ISSN 1479-487X, Vol. 29, no 8, p. 921-929Article in journal (Refereed)
    Abstract [en]

    The white-rot fungus Bjerkandera sp. BOL 13 was evaluated regarding decolorization of four textile dyes Reactive blue 21, Reactive black 5, Reactive orange 13 and Reactive yellow 206. Experiments were performed in batch and continuous modes. The total dye concentration in all experimtents was 100 mg/l. The results of the batch experiments showed that the fungus decolorized all dyes but at different rates. There was, however, an increase in the ultraviolet (UV) absorbance when a medium with a low concentration of nitrogen was used. No increase in UV range was observed when the nitrogen concentration was increased. A continuous experiment was performed to study the decolorization of a mixture of three of the dyes Reactive blue 21, Reactive black 5 and Reactive orange 13. Scanning of inlet and outlet samples showed that the absorbance at the peaks in the visible range decreased by 60-66%. The UV absorbance of the outlet increased during the first days of operation after which it decreased again to reach the same level as the inlet. The hydraulic retention time in the reactor was 3 days. The medium containing the higher nitrogen concentration was used in the continuous experiment.

  • 14.
    Pechsiri, Joseph S
    et al.
    Royal Institute of Technology.
    Thomas, Jean-Baptiste
    Royal Institute of Technology.
    Risén, Emma
    Royal Institute of Technology ; Sweco Environment AB.
    Ribeiro, Maurico S
    Royal Institute of Technology.
    Malmström, Maria E
    Royal Institute of Technology.
    Nylund, Göran
    University of Gothenburg.
    Jansson, Anette
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Welander, Ulrika
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Paiva, Henrik
    University of Gothenburg.
    Gröndahl, Fredrik
    Royal Institute of Technology.
    Energy performance and greenhouse gas emissions of kelp cultivation for biogas and fertilizer recovery in Sweden2016In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 573, p. 347-355Article in journal (Refereed)
    Abstract [en]

    The cultivation of seaweed as a feedstock for third generation biofuels is gathering interest in Europe, however, many questions remain unanswered in practise, notably regarding scales of operation, energy returns on investment (EROI) and greenhouse gas (GHG) emissions, all of which are crucial to determine commercial viability. This study performed an energy and GHG emissions analysis, using EROI and GHG savings potential respectively, as indicators of commercial viability for two systems: the Swedish Seafarm project's seaweed cultivation (0.5 ha), biogas and fertilizer biorefinery, and an estimation of the same system scaled up and adjusted to a cultivation of 10 ha. Based on a conservative estimate of biogas yield, neither the 0.5 ha case nor the up-scaled 10 ha estimates met the (commercial viability) target EROI of 3, nor the European Union Renewable Energy Directive GHG savings target of 60% for biofuels, however the potential for commercial viability was substantially improved by scaling up operations: GHG emissions and energy demand, per unit of biogas, was almost halved by scaling operations up by a factor of twenty, thereby approaching the EROI and GHG savings targets set, under beneficial biogas production conditions. Further analysis identified processes whose optimisations would have a large impact on energy use and emissions (such as anaerobic digestion) as well as others embodying potential for further economies of scale (such as harvesting), both of which would be of interest for future developments of kelp to biogas and fertilizer biorefineries.

  • 15. Perron, Nolwen
    et al.
    Welander, Ulrika
    Degradation of phenol and cresols at low temperatures using a suspended-carrier biofilm process2004In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 55, p. 45-50Article in journal (Refereed)
  • 16.
    Risén, Emma
    et al.
    Kungliga Tekniska Högskolan.
    Gregeby, Erik
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Tartarchenko, Olena
    Kungliga Tekniska Högskolan.
    Blidberg, Eva
    Kungliga Tekniska Högskolan.
    Malmström, Maria
    Kungliga Tekniska Högskolan.
    Welander, Ulrika
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Gröndahl, Fredrik
    Kungliga Tekniska Högskolan.
    Assessment of biomethane production from maritime common reed2013In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 53, p. 186-194Article in journal (Refereed)
    Abstract [en]

    Several ongoing projects are harvesting maritime biomass from the Baltic Sea for eutrophication mitigation and utilisation of the recovered biomass. Some of this biomass comprises common reed (Phragmites australis), one of the most widespread vascular plants on Earth. Reed utilisation from eutrophied coastal areas needs to be evaluated. Therefore, a system analysis was performed of reed harvesting for biofuel and biofertiliser production. The specific objectives of the analysis were to: investigate the methane yield associated with anaerobic co-digestion of reed; make a primary energy assessment of the system; quantify Greenhouse Gas (GHG) savings when a fossil reference system is replaced; and estimate the nutrient recycling potential of the system. The results from energy and GHG calculations are highly dependent on conditions such as system boundaries, system design, allocation methods and selected indicators. Therefore a pilot project taking place in Kalmar County, Sweden, was used as a case study system. Laboratory experiments using continuously stirred tank reactor digesters indicated an increased methane yield of about 220 m3 CH4/t volatile solids from co-digestion of reed. The energy balance for the case study system was positive, with energy requirements amounting to about 40% of the energy content in the biomethane produced and with the non-renewable energy input comprising about 50% of the total energy requirements of the system. The net energy value proved to be equivalent to about 40 L of petrol/t reed wet weight. The potential to save GHG emissions compared with a fossil reference system was considerable (about 80%). Furthermore an estimated 60% of the nitrogen and almost all the phosphorus in the biomass could be re-circulated to arable land as biofertiliser. Considering the combined benefits from all factors investigated in this study, harvesting of common reed from coastal zones has the potential to be beneficial, assuming an appropriate system design, and is worthy of further investigations regarding other sustainability aspects.

  • 17.
    Rupar-Gadd, Katarina
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Strandmark, Gunnar
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Welander, Ulrika
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Biological treatment of air polluted with alpha-pinene.2008Conference paper (Refereed)
  • 18.
    Rupar-Gadd, Katarina
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Avdelningen för Bioenergiteknik.
    Strandmark, Gunnar
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Kemi.
    Welander, Ulrika
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Avdelningen för Bioenergiteknik.
    Biological treatment of air polluted with alpha-pinene2008In: 16 th European Biomass Conference&Exhibition, Eta-Florence Renewable Energies , 2008Conference paper (Refereed)
    Abstract [en]

    A study was performed in order to evaluate if a more hydrophobic biofilter surface could facilitate the removal of hydrophobic pollutants from air. Alpha-pinene was used as a model compound since it is released from wood handling industries e.g. sawmills. Two biofilters were used during the study. One of the filter was filled with perlite soaked with silicone oil while the other was filled with untreated perlite. The removal efficiency was approximately the same for both filters except for the start up period when the oil soaked filter was more efficient.

  • 19.
    Rupar-Gadd, Katarina
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Avdelningen för Bioenergiteknik.
    Welander, Ulrika
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Avdelningen för Bioenergiteknik.
    Emissions from stored biofuels for house-hold use, risks and health effects2008In: 16th European Biomass Conference&Exhibition, 2-6 June 2008, Valencia, Spain, ETA-Florence Renewable Energies , 2008Conference paper (Refereed)
    Abstract [en]

    By varying the storage conditions for lab-scale samples of different biomasses, the mircrobial growth in the samples varied. The microbial acitvity caused heat release and organic emissions were sampled. By measuring the heat release with isothermal calorimetry and organic emissions with solid phase microextraction (SPME) and gas chromatorgraphy with mass spectrometry (GC-MS), it may be posssible to predict the deterioriation in fuel quality, substance losses and health effects for a special fuel storage. The biofuels investigated were pellets made from peat/wood, bark/wood and wood pellets.

  • 20.
    Rupar-Gadd, Katarina
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergi.
    Welander, Ulrika
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergi.
    Prevention of self ignition during storage of biomass fuels2007In: 15th European biomass conference & exhibition, 2007, p. 83-86Conference paper (Refereed)
    Abstract [en]

    The purpose of the work is to increase knowledge in order to prevent self-ignition during large scale storage of biomass fuels. Important goals are to increase the knowledge about the mechanisms involved in the initiation and propagation of self-ignintion. This study is based on measurements of emissions of volatile organic hydrocarbons from two (out of four) wood pellets containing silo experiments, where local auto ignition was initiated by a coiled heating wire placed in the pellet bulk centrally in the silo. The aim was to find a parameter which can be followed in order to estimate the risk for self-ignition. The hydrocarbon gases were sampled using Tenax tubes and the analysis performed on a gaschromatograph equipped with a mass spectrometer. Continuous analyses of the total hydrocarbon gases (THC) were also performed using a flame ionization detector (FID). After the self-heating was initiated , two compounds dominated when the individual hydrocarbins were analyzed, opne unidentified , the other was methyl furan, but the levels of these compounds did not start to increase until after 20 hours when the pyrolysis was well established.

  • 21.
    Rupar-Gadd, Katarina
    et al.
    Institutionen för teknik.
    Widuch, Jonas
    Zander, Carin
    Sanati, Mehri
    Welander, Ulrika
    Instituitionen för teknik.
    Evaluation of the role of microbail activity in self-jheating of stored wood based biofuels2005In: Swedish-Finnish Flame Days, International Flame Research Foundation , 2005, p. 262-267Conference paper (Refereed)
    Abstract [en]

    Self-ignition in storde wood based biofuels is an environmental as well as an economical problem. The amount of biofuels, which is going to be stored, might increase due to the decision taken by the European Union that the emissions of greenhouse gases should decrease. Storage of oragnic material leads to chemical as well as microbial activities. The heat released from aged sawdust (stored outside for three months), dried mixture before it was pressed to pellets and three different kinds of pellets due to microbial activity was measurede with an isothermal calorimeter (TAM Air) under various conditions.- Experiments with and without addition of Cu,Fe and Mn were performed in order to investigate if a catalytical effect could be observed. The results showed that the addition of copper had different efffects depending on which wood material that was studied and the temperature at which the samples had been stored. The addition of Fe or Mn generally did not give any measurable increase in the heat released.

  • 22.
    Sanati, Mehri
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergiteknik.
    Rupar, Katarina
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergiteknik.
    Welander, Ulrika
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergiteknik.
    Bagherpour, Mohammad Bagher
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergiteknik.
    Effects of irrigation and water content of packings on alpha-pinene vapours biofilteration performance2005In: Biochemical Engineering Journal, ISSN 1369-703X, Vol. 24, no 3, p. 185-193Article in journal (Refereed)
    Abstract [en]

    The main objective of this investigation is to determine the effect of different physical parameters on the performance of biofilters, treating

    hydrophobic compounds. In this respect, the effects of irrigation and water content of packings on the removal efficiency of bed in different

    pollutant loading rates, and gas phase flow rates, is studied. Alpha-pinene, which is produced from variety of industrial wood products, pulp

    and paper industries, and fragrance production units, has been selected as a model compound. Since the effectiveness of biofiltration depends

    strongly upon water solubility of compounds, in the case of alpha-pinene (2.5 ppm, at 25 ◦C), the process of waste gas treatment is faced

    with difficulties. In this paper, it is shown that performance of biofilters, treating hydrophobic contaminants, declines due to irrigation. This

    reduction is detected by an increase in the outlet concentration from 11% up to 22.5%. Its magnitude depends on the gas velocity inside the

    biofilter and outlet concentration of the bed. The result indicated that pore blocking along the bed has less effect on the performance reduction

    than diffusion coefficient. Also the inhibitory effects of velocity on biodegradation are considerably higher than the effects of concentration.

    In addition, this compost-based biofilter shows noteworthy higher elimination capacities in comparison with previous studied biofiltration

    systems. In this study, a maximum elimination capacity of 227 gm−3 of packing h−1 is achieved by 95% of removal efficiency. The maximum

    concentration in the inlet gas was 650 mgm−3.

  • 23.
    Sanati, Mehri
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergiteknik.
    Rupar, Katarina
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergiteknik.
    Welander, Ulrika
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergiteknik.
    Bagherpour, Mohammad Bagher
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergiteknik.
    Solid phase micro extraction fibers, calibration for use in biofilter applications2006In: Biochemical Engineering Journal, ISSN 1369-703X, Vol. 31, no 2, p. 107-112Article in journal (Refereed)
    Abstract [en]

    The main purpose of this study is to develop a SPME calibration method suitable for use in evaluation of concentrations of hydrophobic substances

    in environmental samples.

    The analyte used in the experiments was alpha-pinene, a hydrophobic organic compound commonly found in wood, and therefore found in

    wood storage facilities, wood processing industries and wood based biofilters. The SPME fibres were calibrated for different concentrations of

    alpha-pinene at different temperatures and relative humidities. The method was used to evaluate the removal efficiency of a lab-scale biofilter.

  • 24.
    Sanati, Mehri
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Welander, Ulrika
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Rupar-Gadd, Katarina
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Effects of irrigation and water content of packings on2005In: Biochemical Engineering Journal, ISSN 1369-703X, Vol. 24, no 3, p. 185-193Article in journal (Refereed)
    Abstract [en]

    The main objective of this investigation is to determine the effect of different physical parameters on the performance of biofilters, treating

    hydrophobic compounds. In this respect, the effects of irrigation and water content of packings on the removal efficiency of bed in different

    pollutant loading rates, and gas phase flow rates, is studied. Alpha-pinene, which is produced from variety of industrial wood products, pulp

    and paper industries, and fragrance production units, has been selected as a model compound. Since the effectiveness of biofiltration depends

    strongly upon water solubility of compounds, in the case of alpha-pinene (2.5 ppm, at 25 ◦C), the process of waste gas treatment is faced

    with difficulties. In this paper, it is shown that performance of biofilters, treating hydrophobic contaminants, declines due to irrigation. This

    reduction is detected by an increase in the outlet concentration from 11% up to 22.5%. Its magnitude depends on the gas velocity inside the

    biofilter and outlet concentration of the bed. The result indicated that pore blocking along the bed has less effect on the performance reduction

    than diffusion coefficient. Also the inhibitory effects of velocity on biodegradation are considerably higher than the effects of concentration.

    In addition, this compost-based biofilter shows noteworthy higher elimination capacities in comparison with previous studied biofiltration

    systems. In this study, a maximum elimination capacity of 227 gm−3 of packing h−1 is achieved by 95% of removal efficiency. The maximum

    concentration in the inlet gas was 650 mgm−3.

    © 2005 Elsevier B.V. All rights reserved.

  • 25.
    Santos, Graziely Cristina
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Univ. Estadual Paulista, Brazil.
    Forss, Jörgen
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Welander, Ulrika
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Corso, Carlos Renato
    Univ. Estadual Paulista, Brazil.
    Redox mediator evaluation in the azo dye biodegradation2015Conference paper (Refereed)
    Abstract [en]

    Azo dye degradation occurs by means of the oxidation–reduction reactions which have the azo dye acting as final electron acceptor. Some carbon sources can act as electron donors because the products of their metabolism act as redox mediators. In order to enhance the dye biodegradation process, the present study aims to evaluate the decolorization of an artificial wastewater, containing the azo dye Direct Red 75 (DR75), led by a microbial consortium from rice husks, testing the effect in the process of glucose and yeast extract as carbon sources. Samples with and without 0.1 M Sodium phosphate buffer were also analysed. The decolorization was measured by means UV-VIS spectrophotometry. The percentage of decolorization of the samples over the time indicates that the sample with yeast extract, rinse water of rice husks and without buffer presented the best decolorization rate, about 80%. Therefore, the results presented in this study may also suggest that yeast extract is a better carbon source for dye biodegradation than glucose.

  • 26. Türgay, Orcun
    et al.
    Ersöz, Gülin
    Atalay, Süheyda
    Forss, Jörgen
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Welander, Ulrika
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Treatment of Azo Dyes in Textile Industry Wastewater by Biological and/or Chemical Methods2011In: Separation and Purification Technology, ISSN 1383-5866, E-ISSN 1873-3794, Vol. 79, no 1, p. 26-33Article in journal (Refereed)
  • 27.
    Welander, Ulrika
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergiteknik.
    Decolorization of synthetic and real textile wastewater by the use of white-rot fungi2006In: Enzyme and Microbial Technology, ISSN 0141-0229, Vol. 38, no 1, p. 94-100Article in journal (Refereed)
    Abstract [en]

    Batch and continuous reactors inoculated with white-rot fungi were operated in order to study decolorization of textile dyes. Synthetic

    wastewater containing either Reactive Blue 4 (a blue anthraquinone dye) or Reactive Red 2 (a red azo dye) was used during the first part of

    the study while real wastewater from a textile industry in Tanzania was used in the later part. Trametes versicolor was shown to decolorize

    both Reactive Blue 4 and Reactive Red 2 if glucose was added as a carbon source. Reactive Blue 4 was also decolorized when the fungus

    was allowed to grow on birch wood discs in a continuous biological rotating contactor reactor. The absorbance at 595 nm, the wavelength at

    which the dye absorbs at a maximum, decreased by 70% during treatment. The initial dye concentration in the medium was 200 mg/l and the

    hydraulic retention time in the reactor 3 days. No glucose was added in this experiment. Changes of the absorbance in the UV range indicated

    that the aromatic structures of the dyes were altered. Real textile wastewater was decolorized by Pleurotus flabellatus growing on luffa sponge

    packed in a continuous reactor. The reactor was operated at a hydraulic retention time of 25 h. The absorbance at 584 nm, the wavelength at

    which the wastewater absorbed the most, decreased from 0.3 in the inlet to approximately 0.1 in the effluent from the reactor.

  • 28.
    Welander, Ulrika
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergiteknik.
    Decolorization of the textile dyes Reactive Red 2 and Reactive2006In: Enzyme and Microbial Technology, ISSN 0141-0229, Vol. 39, no 1, p. 32-37Article in journal (Refereed)
    Abstract [en]

    The decolorization of two different textile dyes, Reactive Red 2 and Reactive Blue 4, was studied in batch as well as continuous experiments

    using Bjerkandera sp. Strain BOL 13. The batch experiments were performed to study the decolorization of the dyes separately as well as in a

    mixture. The results from the experiments showed that the fungus decolorized both dyes. The absorbance was measured at 538 and 595 nm, the

    peak absorbance wavelengths of the red and blue dyes respectively. The absorbance decreased with 99% at both 538 and 595 nm in the experiments

    in which the dyes were studied separately at a concentration of 100 mg/l. The corresponding figure for the experiment in which the dyes were

    studied in a mixture was 98%. A continuous rotating biological contactor was then used to study the decolorization of mixtures of the two dyes at

    three different concentrations, e.g. 50, 100 and 200 mg/l of each of the dyestuff. The decrease in absorbance at 538 nm was 96% at the two lower

    dye concentrations while it was 81% at the highest concentration. The corresponding figures at 595 nm were 94 and 80%. The hydraulic retention

    time was 3 days. Scanning of the absorbance between 200 and 800 nm showed that three peaks disappeared in the UV range during treatment (246,

    283 and 323.5 nm) and that a new plateau was formed around 270 nm.

  • 29.
    Welander, Ulrika
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergi.
    Hydrogen peroxide degradation by immobilized cells of alkaliphilic Bacillus halodurans2006In: Biocatalysis and Biotransformation, ISSN 1024-2422, Vol. 24, no 3, p. 215-222Article in journal (Refereed)
    Abstract [en]

    Whole cells of Bacillus halodurans LBK 261 were used as a source of hydrogen peroxide. The organism B halodurans grown at 55 C and pH 10, yielded a maximum catalase activity of 275 U g-1 (Wet wt.) cells. The catalase in the whole cells was active over a broad range of pH with a maximum at pH 8-9. The enzyme was optimally active at 55 C, but had low stability above 40 C. The whole cell biocatalyst exhibited a Km of 6.6 mM for H2O2 and Vmax of 707 mM H2O2 min-1 g-1 wet wt. cells, and showed saturation kinetics at 50 mM H2O2. The cells were entrapped in calcium alginate and used for H2O2 degradation at pH 9 in batch and continuous mode. In the batch process, the immobilized prepration containing 1.5 g (wet wt.) cells could be recycled at least four times for complete degradation of the peroxide in 50 ml solution at 25 C. An excess of immobilized biocatalyst could be used in a continuous stirred tank reactor for an average of 9 days at temperatures upto 55C, and in a packed bed (PBR) for 5 days before the beads started to deform.

  • 30. Welander, Ulrika
    Identification by gas chromatography of organic constituents in leachate from sanitary landfills1997In: Resources and Environmental Biotechnology, Vol. 1, p. 283-296Article in journal (Refereed)
  • 31. Welander, Ulrika
    Microbial degradation of organic pollutants in soil in a cold climate2005In: Soil & sediment contamination, ISSN 1532-0383, E-ISSN 1549-7887, Vol. 14, p. 281-291Article in journal (Refereed)
    Abstract [en]

    Cold-adaptyed microorganisms are potentially interesting for use in environmental biotechnology applications since a large part of the biosphere has low temperatures during at least parts of the year. Many studies have shown that both oil-contaminated and uncontaminated soils in the Arctic, the Antarctic and the Alps contain microbes that can degrade different hydrocarbons deriving from oils. A few studies have also been conducted on degradation of herbicides in soils at low temperatures. Furthermore, phenols and some polychlorinated biphenyl (PCB) congeners have proved to be degradable at low temperatures, using microorganisms isolated from sediments or soils. Additions of nitrogen and phosphorous to polluted soils have been shown to enhance the degradation of hydrocarbons in many cases. Bioaugmentation with hydrocarbon degrading cold-adapted microorganisms has given varying results. THe inoculatde microorganisms have probably been out-competed by the indigenous microorganisms in some cases. Different ways to increase the efficiency of microbial degradation of organic pollutants in soil in a cold climate is discussed.

  • 32.
    Welander, Ulrika
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Forss, Jörgen
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Decolourization of reactive azo dyes with microorganisms growing on soft wood chips2009In: International Biodeterioration & Biodegradation, ISSN 0964-8305, E-ISSN 1879-0208, ISSN 0964-8305, Vol. 63, p. 752-758Article in journal (Refereed)
    Abstract [en]

    The decolourization of a mixture of 200 mg/l each of Reactive Black 5 and Reactive REd 2 dye was studied in batch experiments using microorganisms growing on forest residue wood chips in combination with or without added white-rot fungus, Bjerakndera sp. BOL 13. The study was performed as a first stage in the development of a relatively simple treatement process for textile wastewater, designed to work in developing countries. Forest residue wood chips contain a mixture of fungi and bacteria which is an advantage when complex molecules should be degraded. The wood chips furthermore provide the microorganisms with carbon source which make the addition of e.g. glucose unnecessary. The results showed that the microorganisms growing on the forest residue wood chips decolourized the mixture of the two dyes; adding extra nutrients approximately doubled the decolourization rate. The time needed for decolourization was approximately 18 days when nutrients were added. Lignocellulosic material is complex and so were the analysis, microorganisms were therfore transferred to ordinary soft wood chips from forest residue wood chips, Decolourization was measured with spectrophotometer an in order to determine intermediates HPLC was used.

  • 33.
    Welander, Ulrika
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Hejazi, Parisa
    Berenberg, Fredrik
    Isik, Güldem
    Rupar-Gadd, Katarina
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Strandmark, Gunnar
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Shojaosadati, Abbas
    Treatment of alpha-pinene contaminated air using biofilters with and without silicone oil2010In: Environmental Progress & Sustainable Energy, ISSN 1944-7442, E-ISSN 1944-7450, Vol. 29, no 3, p. 313-318Article in journal (Refereed)
    Abstract [en]

    Two biofilters equal in size were filled with perlite for treatment of -pinene-contaminated air. The perlite used for one of the biofilters was partially coated with silicone oil to make the surface of the particles more hydrophobic. The filters were run at 1.5, 2.5, and 5 L/min airflow rate (3.1, 1.9, and 0.9-min retention time). The filters were operated for 5.5 months. The results showed that the silicone oil-coated filter performed better at 2.5 L/min with a maximum elimination capacity of 20 g/(m3 h) in comparison with 15 g/(m3 h) for the filter without oil. The efficiency was approximately the same for both filters at 1.5 L/min (40 g/m3 h), whereas it was slightly higher for the without oil filter at 5 L/min [35 g/(m3 h)]. The flow rate was set to 2.5 L/min once more (day 151). The results showed that the elimination capacity had increased to 35 g/(m3 h) and that the efficiency of both filters was approximately the same. The difference in results between the initial run and the later run at 2.5 L/min is probably depending on that the number of microorganisms had increased during the experiment and that the oil-containing biofilter adsorbed -pinene to a higher extent than the biofilter without silicone oil during the start-up period. © 2009 American Institute of Chemical Engineers Environ Prog, 2010

  • 34. Welander, Ulrika
    et al.
    Henrysson, Tomas
    Degradation of organic compounds in a municipal landfill leachate treated in a suspended-carrier biofilm process1998In: Water environment research, ISSN 1061-4303, E-ISSN 1554-7531, Vol. 70, p. 1236-1241Article in journal (Refereed)
  • 35. Welander, Ulrika
    et al.
    Henrysson, Tomas
    Physical and chemical treatment of a nitrified leachate from a municipal landfill1998In: Environmental technology, ISSN 0959-3330, E-ISSN 1479-487X, Vol. 19, p. 591-599Article in journal (Refereed)
  • 36.
    Welander, Ulrika
    et al.
    University of Kalmar, Department of Technology.
    Henrysson, Tomas
    Welander, Thomas
    Biological nitrogen removal from municipal landfill leachate in a pilot-scale suspended carrier biofilm process1998In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 32, p. 1564-1570Article in journal (Refereed)
  • 37. Welander, Ulrika
    et al.
    Henrysson, Tomas
    Welander, Thomas
    Nitrification of landfill leachate using suspended-carrier biofilm technology1997In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 31, p. 2351-2355Article in journal (Refereed)
  • 38.
    Wollak, Birte
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Forss, Jörgen
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Welander, Ulrika
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Evaluation of blue mussels (Mytilus edulis) as substrate for biogas production in Kalmar County (Sweden)2018In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 111, p. 96-102Article in journal (Refereed)
    Abstract [en]

    The Baltic Sea is an over-fertilized inland sea; the blue mussels have potential to absorb nutrients as well as being a source of renewable energy in the form of biogas. The aim of this study was to evaluate technology to utilize blue mussels for biogas production in a pilot scale. Blue mussels (Mytilus edulis) were anaerobically digested in a two-stage digestion process (430 L), consisting of a percolation bed and an up-flow anaerobic sludge blanket reactor. Frozen mussels with shells were placed in the percolation bed and digestion was performed at 36 oC during 37 days. The methane potential achieved with this technique was 310 L kg-1 volatile solid substances (273.15 K, 101.3 kPa). This result suggests that blue mussels can be efficiently digested in a larger scale and have the potential of contributing to a sustainable energy mix in the Baltic region and at the same time decrease the eutrophication of the Baltic Sea.  No addition of nutrients and no pretreatment of the mussels (peeling) were needed.

1 - 38 of 38
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