| 1. |
- Granström, Karin, 1974-, et al.
(författare)
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Biogas from algae farmed in pulp and paper mill wastewater
- 2015
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Ingår i: GGROS 2015, Örnsköldsvik, Sweden, 23-25 March 2015..
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Konferensbidrag (refereegranskat)abstract
- Pulp and paper mills have waste streams that can be used for the farming of algae. The mills wastewater treatment provides heat to the algae ponds and the flue gas provides carbon dioxide. A current project is aiming at producing oil, for biodiesel or lubricating oil, from mill-farmed algae. Ten pools have been constructed and seeded with different strains of algae. After harvest and separation of oil, there is a leftover algae pulp. The fate of this algae remnant is an important part in achieving economic and energy viability for the whole process.The purpose of this work was to study the potential to produce biogas from algae grown in pulp and paper mill wastewaters, for different algae strains and pond conditions, with differing degrees of oil separation before the anaerobic digestion stage. The methane potential of the various algae pulps was tested by anaerobic digestion batch assays under thermophilic conditions for 23 days. Pre-treatment of substrate is sometimes done in order to reduce the necessary retention time of biogas production. One batch of algae was subjected to either thermal pre-treatment or NaOH or comminution, to assess the effect on these methods on methane production.Ammonia concentration and pH in the digestate was analyzed to monitor the anaerobic digestion process, and the algae pulp’s content of fat, protein and carbohydrates were analyzed to characterize the substrate. In addition, the dewaterability of algae and of algae digestate was examined, as the dewaterability affects transport costs and possible use of the digestate.During the first year of operation, the algae in the range pond produced 186 ml CH4/g VS. The pre-treatments did not significantly affect the methane potential. The second year of operation saw more adapted strains of algae which are expected to produce somewhat different results [data from these experiments can be presented at the conference]. The research is of importance for the development of the biogas market as new substrates are needed to reach the volumes that are necessary to achieve economic viability for biogas plants. By characterizing the algae, it should be easier to see which role they are suitable to play in a co-digestion mix. Furthermore, the production of bio-oil and biogas together benefit the bioenergy system as a whole.
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| 2. |
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| 3. |
- Granström, Karin, 1974-
(författare)
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Regler för hantering av rötrest
- 2014
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- InnehållsförteckningINLEDNINGPROBLEM MED ATT TA TILLVARA RÖTRESTTungmetallerSmittaREGLERING AV ANVÄNDANDET AV RÖTREST SOM GÖDNINGCertifiering av biogödselHygieniseringskrav för biogödselCertifiering av rötslamHygieniseringskrav för rötslamACCEPTANS?MÖJLIGHETER OCH RISKER MED SAMRÖTNINGREFERENSER
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| 4. |
- Bourne, D., et al.
(författare)
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Is adding charcoal to soil a good method for CO2 sequestration? - : Modeling a spatially homogeneous soil
- 2014
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Ingår i: Applied Mathematical Modelling. - : Elsevier. - 0307-904X .- 1872-8480. ; 38:9-10, s. 2463-2475
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Tidskriftsartikel (refereegranskat)abstract
- Carbon sequestration is the process of capture and long-term storage of atmospheric carbon dioxide (CO2) with the aim to avoid dangerous climate change. In this paper, we propose a simple mathematical model (a coupled system of nonlinear ODEs) to capture some of the dynamical effects produced by adding charcoal to fertile soils. The main goal is to understand to which extent charcoal is able to lock up carbon in soils. Our results are preliminary in the sense that we do not solve the CO2 sequestration problem. Instead, we do set up a flexible modeling framework in which the interaction between charcoal and soil can be tackled by means of mathematical tools.We show that our model is well-posed and has interesting large-time behaviour. Depending on the reference parameter range (e.g., type of soil) and chosen time scale, numerical simulations suggest that adding charcoal typically postpones the release of CO2. © 2013 Elsevier Inc.
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| 5. |
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| 6. |
- Mikhelkis, Lena, et al.
(författare)
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Techno-economic and partial environmental analysis of carbon capture and storage (CCS) and carbon capture, utilization and storage (CCU/S): Case study from proposed waste-fed district-heating incinerator in Sweden.
- 2020
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Ingår i: Sustainability. - : MDPI AG. - 2071-1050. ; 12:15
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Tidskriftsartikel (refereegranskat)abstract
- Sweden aspires to become totally carbon dioxide-neutral by 2045. Indisputably, what is needed is not just a reduction in emissions of CO2 (greenhouse gases in general) from the technosphere, but also manipulated diversion of CO2 from the atmosphere to ‘traps’ in the lithosphere, technosphere, hydrosphere and biosphere. The case study in this paper is focused on Stockholm Exergi’s proposed waste-to-energy incineration plant in Lövsta, which is keen on incorporating carbon capture and storage (CCS), but is also interested in understanding the potential of carbon capture, utilisation and storage (CCU/S) in helping it to achieve ‘carbon-dioxide-negativity’. Waste-to-energy incineration plants (in cases where the petro-plastics in the waste mix can be substantially reduced) are a key component of a circular bio-economy, though the circularity here pertains to recovering energy from materials which may or may not be recyclable. CCS (storage in the North Sea) is compared with CCU/S (CO2 sintered into high-quality building blocks made of recycled slag from the steel sector) from techno-economic and environmental perspectives. The comparative analysis shows, inter alia, that a hybridized approach – a combination of CCS and CCU/S, is worth investing in. CCU/S, at the time of writing, is simply a pilot project in Belgium – a possible creatively-destructive technology which may or may not usurp prominence from CCS. The authors believe that political will and support with incentives, subsidies and tax rebates are indispensable to motivate investments in such ground-breaking technologies and looking away from the easier route of paying carbon taxes or purchasing emission rights.
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| 7. |
- Ståhl, Magnus, 1973-
(författare)
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Minska energianvändningen i pelletspressen och öka pelletskvaliteten
- 2013
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The wood fuel pellet industry demands energy efficient solutions for their production since these not only save energy but also money. One way of achieving this is to use additives. Choosing the right additive can save money but also increase the quality of the pellets, a win win situation. In this work, it is investigated how different kind of additives affect the energy use of the pelletizing equipment and also how it affects the durability of pellets. The best results were achieved using oxidized cornstarch as an additive during pellet production, it not only decreases the energy used the most but also produce the pellets with highest durability.
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| 8. |
- Wikström, Fredrik, 1964-, et al.
(författare)
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Packaging and Food Waste Behavior
- 2017
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Ingår i: Reference Module in Food Sciences. - : Elsevier. - 9780081005965 ; , s. 1-4
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Bokkapitel (refereegranskat)abstract
- Packaging saves food by protecting the content from physical and chemical degradation during the distribution and storage processes. However, packaging can do much more than that. This article explores how the design of a package may help, or indeed hinder, the consumer to avoid wasting food. A number of packaging attributes influence consumer behavior. The influence is different depending on the product‘s characteristics and the needs of the consumer. For many products, it might be better to add packaging material, for example, by creating smaller sizes of the product to reduce food waste and the overall environmental impact.
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| 9. |
- Al-Hazmi, Hussein E., et al.
(författare)
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Polysaccharide nanocomposites in wastewater treatment : A review
- 2024
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Ingår i: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 347
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Forskningsöversikt (refereegranskat)abstract
- In modern times, wastewater treatment is vital due to increased water contamination arising from pollutants such as nutrients, pathogens, heavy metals, and pharmaceutical residues. Polysaccharides (PSAs) are natural, renewable, and non-toxic biopolymers used in wastewater treatment in the field of gas separation, liquid filtration, adsorption processes, pervaporation, and proton exchange membranes. Since addition of nanoparticles to PSAs improves their sustainability and strength, nanocomposite PSAs has gained significant attention for wastewater treatment in the past decade. This review presents a comprehensive analysis of PSA-based nanocomposites used for efficient wastewater treatment, focusing on adsorption, photocatalysis, and membrane-based methods. It also discusses potential future applications, challenges, and opportunities in adsorption, filtration, and photocatalysis. Recently, PSAs have shown promise as adsorbents in biological-based systems, effectively removing heavy metals that could hinder microbial activity. Cellulose-mediated adsorbents have successfully removed various pollutants from wastewater, including heavy metals, dyes, oil, organic solvents, pesticides, and pharmaceutical residues. Thus, PSA nanocomposites would support biological processes in wastewater treatment plants. A major concern is the discharge of antibiotic wastes from pharmaceutical industries, posing significant environmental and health risks. PSA-mediated bio-adsorbents, like clay polymeric nanocomposite hydrogel beads, efficiently remove antibiotics from wastewater, ensuring water quality and ecosystem balance. The successful use of PSA-mediated bio-adsorbents in wastewater treatment depends on ongoing research to optimize their application and evaluate their potential environmental impacts. Implementing these eco-friendly adsorbents on a large scale holds great promise in significantly reducing water pollution, safeguarding ecosystems, and protecting human health.
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| 10. |
- Al-Hazmi, Hussein E., et al.
(författare)
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Wastewater reuse in agriculture : Prospects and challenges
- 2023
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Ingår i: Environmental Research. - : Elsevier. - 0013-9351 .- 1096-0953. ; 236
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Forskningsöversikt (refereegranskat)abstract
- Sustainable water recycling and wastewater reuse are urgent nowadays considering water scarcity and increased water consumption through human activities. In 2015, United Nations Sustainable Development Goal 6 (UN SDG6) highlighted the necessity of recycling wastewater to guarantee water availability for individuals. Currently, wastewater irrigation (WWI) of crops and agricultural land appears essential. The present work overviews the quality of treated wastewater in terms of soil microbial activities, and discusses challenges and benefits of WWI in line with wastewater reuse in agriculture and aquaculture irrigation. Combined conventional-advanced wastewater treatment processes are specifically deliberated, considering the harmful impacts on human health arising from WWI originating from reuse of contaminated water (salts, organic pollutants, toxic metals, and microbial pathogens i.e., viruses and bacteria). The comprehensive literature survey revealed that, in addition to the increased levels of pathogen and microbial threats to human wellbeing, poorly-treated wastewater results in plant and soil contamination with toxic organic/inorganic chemicals, and microbial pathogens. The impact of long-term emerging pollutants like plastic nanoparticles should also be established in further studies, with the development of standardized analytical techniques for such hazardous chemicals. Likewise, the reliable, long-term and extensive judgment on heavy metals threat to human beings's health should be explored in future investigations.
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