| 1. |
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Bioblitz i Arkelstorp 16-17 augusti 2019
- 2020
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Samlingsverk (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract
- Arkelstorpsviken är den nordvästra delen av Oppmannasjön, som ären av Skånes största sjöar. Idén att genomföra en så kallad Bioblitzvid Arkelstorpsviken föddes under ett styrelsemöte i projektet "En viki Sjöriket Skåne" som är ett samarbete mellan Oppmanna Vånga Bygderåd och Högskolan Kristianstad. Projektets främsta syfte är att hitta en lösning på den kraftiga övergödningen i Arkelstorpsviken. Detta är ett ”Leader”-finansierat projekt, vilket innebär att stommen i projektetär lokal förankring. Det fanns röster i byn som kände att man gav området onödigt dåligt rykte genom att ständigt lyfta fram problemen med vattenstatusen i sjön. Under ett styrelsemöte 30 sep 2018 föddes iden att genom en Bioblitz lyfta fram de positiva värdena i och kring sjön. Den naturliga samarbetspartnern för detta projekt var forskningsmiljön MABH (Man & Biosphere Health) vid Högskolan Kristianstad,vars medlemmar tillsammans besitter en mycket bred biologisk kunskap.Med MABH i ryggen var alltså kompetensen säkrad för att genomföra en Bioblitz. Inbjudningar skickades ut till lokala naturorganisationerför att hitta ännu fler experter som kunde hjälpa till med särskilda artgrupper. Samtidigt jobbade man aktivt lokalt med att försöka engagera intresserad allmänhet. Inbjudningar och direktreklam skickades ut till samtliga hushåll med postadress Arkelstorp. I ett försök att synas genom mediebruset anordnades en tävling, som gick ut på att gissa antalet arter (taxa) som hittades under Bioblitzen. Två lokala företag ställde upp och första priset för den vuxna individ som gissade närmstvar en 3-rätters måltid på Bäckaskogs Slott. De yngre tävlande kunde vinna en kanotutflykt med familjen på Ivögården.
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| 2. |
- Lipnizki, Frank, et al.
(författare)
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Membrane fouling and cleaning in lignocellulosic biorefineries
- 2023
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Konferensbidrag (refereegranskat)abstract
- IntroductionThe pulp and paper sector is a key global industry. Presently, pulp mills prioritize the production of pulp, fibers, and electricity. By transforming traditional pulp mills into lignocellulosic biorefineries, they can become a key element of a future, circular bioeconomy. To accomplish this, pulp mills need to close their loops and optimize the use of the lignocellulosic feedstock, not just for pulp and fiber production but also for co-production of biochemicals, biofuels, and other high-value materials. Membrane processes can play an important role in this transition as electrifiable, low energy and high-selective separation processes. A key challenge and important cost factor when using membrane processes is membrane fouling and subsequent membrane cleaning. In this lecture two studies on membrane fouling and cleaning with reference to two process streams in the pulping industry will be presented. Bleaching plant effluent from sulphite pulping processIn this study tubular polymeric UF membrane used for several months for concentration of bleach plant effluent in a magnesium sulphite pulp mill were investigated. The initial analysis of the fouling layer on the membrane was conducted in combination of scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) and attenuated total reflection Fourier transformed infrared spectroscopy (ATR-FTIR). Additionally, high-performance anion-exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD) and heteronuclear single quantum coherence 2D nuclear magnetic resonance spectroscopy (HSQC-2D-NMR) were used. The comprehensive analysis showed that a 4.5 µm thick fouling layer consisting mainly of magnesium had been formed on the membrane during its lifespan. Based on this, alkaline membrane cleaning was tested on samples of the fouled membrane and SEM-EDS analysis was conducted before and after cleaning. Before the analysis the membrane samples were placed for 1h and 20 h in the alkaline cleaning solution. The subsequent analysis showed that a 1 h exposure to the cleaning agent had hardly any impact on the fouling layer, while after 20 h the fouling layer nearly completely disappeared. Hence, this study underlined the importance of contact time in membrane cleaning. Process water from a thermo-mechanical pulp mill The second study is related to the development of a process for the concentration and purification of hemicellulose in a thermomechanical pulp mill process water. Flat-sheet polymeric UF membranes fouled and cleaned during lab-scale conditions were analyzed using various techniques such as SEM, ATR-FTIR, Brunauer-Emmett-Teller nitrogen adsorption desorption analysis (BET) and Quartz crystal microbalance with dissipation monitoring (QCM-D). The studies revealed among others that membrane fouling resulted in gel layer formation, blocking and pore narrowing. It was further shown that the hemicelluloses i.e. galactoglucomannan were key components of the membrane fouling layer. A cleaning study using alkaline and enzymatic cleaning showed that alkaline cleaning was very efficient to remove the following layer but in the longer term a regular additional enzymatic cleaning could boost the membrane capacity over the membrane lifetime. Conclusions and outlookBoth fouling and cleaning are important for the sustainable implementation of membrane processes in lignocellulosic biorefineries. These two studies revealed the importance of cleaning solution, contact time and cleaning chemical sequency. Overall, this work will support the development of new cleaning protocols for membrane processes in lignocellulosic biorefineries and thus the establishment of membrane processes in the industry. Acknowledgements This work is related to Task XVII: “Membrane Processes in Biorefineries” of the IEA Technology Collaboration Programme: “Industrial Energy-Related Technologies and Systems (IETS-TCP)”.
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| 3. |
- Olsson, Johanna, et al.
(författare)
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An extensive parameter study of hydrotropic extraction of steam-pretreated birch
- 2023
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Ingår i: Biomass Conversion and Biorefinery. - : Springer Science and Business Media LLC. - 2190-6815 .- 2190-6823. ; 13:5, s. 4001-4009
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Tidskriftsartikel (refereegranskat)abstract
- Efficient fractionation of lignocellulosic biomass is an important step toward the replacement of fossil-based products. However, the utilisation of all of the components in biomass requires various fractionation techniques. One promising process configuration is to apply steam explosion for the recovery of hemicelluloses and a subsequent hydrotropic extraction step for the delignification of the remaining solids. In this work, the influence of residence time, temperature and biomass loading on lignin recovery from birch using sodium xylene sulphonate as a hydrotrope was investigated. Our results show that residence time, temperature and biomass loading correlate positively with lignin extraction, but the effects of these parameters were limited. Furthermore, when steam explosion was implemented as the initial step, hydrotropic extraction could be performed even at room temperature, yielding a lignin extraction of 50%. Also, hydrothermal degradation of the material was necessary for efficient delignification with sodium xylene sulphonate, regardless of whether it occurs during steam explosion pretreatment or is achieved at high temperatures during the hydrotropic extraction.
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| 4. |
- Rudolph, Gregor, et al.
(författare)
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Comprehensive Analysis of Foulants in an Ultrafiltration Membrane Used for the Treatment of Bleach Plant Effluent in a Sulfite Pulp Mill
- 2021
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Ingår i: Membranes. - : MDPI AG. - 2077-0375. ; 11:3
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Tidskriftsartikel (refereegranskat)abstract
- Fouling is a major obstacle in the introduction of membrane processes in new applications in the pulping industry. Due to the complex nature of the feed solutions, complementary analysis methods are usually needed to identify the substances involved. Four different methods were used for the comprehensive analysis of a membrane removed from an ultrafiltration plant treating alkaline bleach plant effluent in a sulfite pulp mill to identify the substances causing fouling. Magnesium was detected both on the membrane surface and in the nonwoven membrane backing and a small amount of polysaccharides was detected after acid hydrolysis of the fouled membrane. This study provides information on foulants, which can be used to improve processing conditions and cleaning protocols and thus the membrane performance in pulp mill separation processes. It also provides an overview of the usefulness of various analytical methods.
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| 5. |
- Rudolph, Gregor, et al.
(författare)
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In situ real-time investigations on adsorptive membrane fouling by thermomechanical pulping process water with quartz crystal microbalance with dissipation monitoring (QCM-D)
- 2021
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Ingår i: Separation and Purification Technology. - : Elsevier BV. - 1383-5866. ; 254
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Tidskriftsartikel (refereegranskat)abstract
- Membrane processes are essential for the success of lignocellulosic biorefineries, but membrane fouling is still a major problem and the single most important reason for the relatively slow acceptance of membrane technology in this industrial application. It is therefore of the utmost importance to find methods that enable the study of the fouling development when processing new types of feed solutions. Although ex situ analysis allows the composition of the fouling layer to be determined, the processes leading to its build-up remain unknown. In this study, quartz crystal microbalance with dissipation monitoring (QCM-D) was used to study adsorptive fouling in situ. By using QCM-D, the development of fouling over time can be studied. Fouling of three fractions of a thermomechanical pulping process water (feed, microfiltration retentate and permeate) were studied on QCM-D sensors coated with a polymer used in commercial polysulfone membranes. The retentate contained mainly colloidal extractives and the permeate hemicelluloses. In the case of the retentate, adsorption was almost immediate and the greatest increase in mass was observed. In case of the permeate, the increase in mass was slowest but at steady state the adsorbed mass was similar to the adsorbed mass of the process water. After rinsing with water, an irreversibly attached network of hemicelluloses remained on the polymer surface while the colloidal extractives were washed away. Overall, the study shows that in situ real-time monitoring of adsorptive membrane fouling combined with additional ex situ analysis generates valuable understanding on the evolution of membrane fouling in lignocellulosic biorefineries.
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| 6. |
- Rudolph-Schöpping, Gregor, et al.
(författare)
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Comparison of membrane fouling during ultrafiltration with adsorption studied by quartz crystal microbalance with dissipation monitoring (QCM-D)
- 2023
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Ingår i: Journal of Membrane Science. - : Elsevier BV. - 0376-7388. ; 672
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Tidskriftsartikel (refereegranskat)abstract
- Even though membrane technology is used in numerous industrial applications, membrane fouling is still a major challenge. Valuable information on the formation kinetics and structure of the fouling layer can be obtained by in situ real-time monitoring. Quartz crystal microbalance with dissipation monitoring (QCM-D) enables the study of adsorptive fouling in situ on a model membrane. However, so far, there has been no in-depth investigation as to what extent observations from QCM-D relate to fouling during membrane filtration. This gap is here approached by comparing membrane fouling during ultrafiltration with QCM-D measurements using the same feed (process water from thermomechanical pulping) and the same material in the polymer film as in the membrane (hydrophilized polysulfone). The performance at two temperatures (25 °C and 50 °C) was studied. Fouling was analyzed by flux measurements, changes in frequency and dissipation over time with QCM-D, and surface characterization of the membrane samples and QCM-D sensors. QCM-D revealed an increase in rigidity of the fouling layer at 50 °C with time, which was consistent with a higher irreversible resistance during ultrafiltration. This was presumably caused by structural changes of hemicelluloses and colloidal wood extractive droplets in the process water at the higher temperature. The study shows that findings from QCM-D on the attachment of foulants on polymer films are comparable to membrane fouling. Thus, QCM-D, together with complementary analytical methods, can provide valuable insights on the development of membrane fouling of e.g., industrial wastewater.
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| 7. |
- Shi, Ziyi, et al.
(författare)
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Continuous catalytic pyrolysis of biomass using a fluidized bed with commercial-ready catalysts for scale-up
- 2023
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Ingår i: Energy. - : Elsevier Ltd. - 0360-5442 .- 1873-6785. ; 273
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Tidskriftsartikel (refereegranskat)abstract
- The use of catalytic fast pyrolysis (CFP) of biomass to produce high-quality bio-oils as potential substitutes for conventional fuels plays an essential role in the decarbonization of the world. In this study, continuous CFP tests of sawdust using three commercial-ready catalysts were performed. The overall objective is to screen appropriate catalysts and catalyst loading amounts for further commercialization and upgrading by evaluating the quality of the organic fraction bio-oils and clarifying the relationship between the hydrogen-to-carbon atomic effective (H/Ceff) ratio and bio-oil yield. The results displayed that, owing to a cracking effect of the catalyst, all catalytic cases had higher H/Ceff ratios and larger relative area percentages of hydrocarbons determined by NMR. Thermogravimetric analysis reveals that, compared to non-catalytic bio-oils, catalytic bio-oils showed more distillates in the diesel range. Increasing the catalyst-loading amount also showed the same effect. Overall, all bio-oil products from catalytic cases had H/Ceff ratios higher than 0.6, indicating the production of promising oil for hydrodeoxygenation. By analyzing and fitting the data from this work and comparing with the literature, it could be concluded that its yield would decrease as the bio-oil product quality increases (the H/Ceff ratios increase). © 2023 The Authors
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| 8. |
- Thuvander, Johan, et al.
(författare)
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Techno-economic impact of air sparging prior to purification of alkaline extracted wheat bran hemicelluloses by membrane filtration
- 2020
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Ingår i: Separation and Purification Technology. - : Elsevier BV. - 1383-5866. ; 253
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Tidskriftsartikel (refereegranskat)abstract
- Air sparging of alkaline-extracted wheat bran hemicelluloses prior to ultrafiltration has been shown to increase the flux. The techno-economic impact of air sparging on the cost of concentration and purification of wheat bran hemicelluloses by ultrafiltration and diafiltration was studied in this work. Two alkaline hemicellulose solutions were purified until the conductivity of the diafiltration permeate was <1 mS/cm. Both solutions were pretreated by the removal of suspended matter using dead-end filtration with diatomaceous earth as filter aid. One of the solutions was further pretreated by air sparging for 4 h at 80 °C prior to concentration by ultrafiltration. Air sparging increased the average flux during ultrafiltration from 52 L/m2 h to 151 L/m2 h, and during diafiltration from 46 L/m2 h to 130 L/m2 h. A higher diafiltration factor was needed for the air-sparged solution, requiring a higher amount of diafiltration water. However, the cost of purifying the hemicelluloses was reduced from 1375 €/ton hemicelluloses to 1122 €/ton by sparging the solution with air prior to membrane filtration.
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