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Techno-economic analysis of integrating hydrothermal carbonisation (HTC) in the downstream of the anaerobic digestion process- A Stormossen biogas plant case study
No full textSewage sludge is a byproduct of biological wastewater treatment and volumes produced keep increasing due to the global population growth, industrialization and urbanization. It is estimated that the European Union countries produce about 10 million tonnes of sewage sludge per year on average, and over 1.3 billion tonnes is produced annually globally and is expected to grow to 2.2 billion tonnes by 2025 globally. The sewage sludge produced has a high moisture content of between 97 and 98% and contains nutrients and impurities such as, nitrogen, phosphorus and potassium, organic matter, heavy metals, microplastics, pharmaceuticals, organic contaminants and pathogens. Whilst biogas production using anaerobic digestion (AD) is the best available technology (BAT) for sewage sludge handling, the disposal of the byproduct sewage sludge digestate still poses a challenge.
The objective of this study is to assess whether it is technically and economically motivating to integrate the hydrothermal carbonisation (HTC) process in the biogas production plant by looking at the downstream of the biogas production process. The HTC process is an imitation of the natural formation of coal, by reacting high moisture biomass in subcritical water. This phenomenon happens at temperature ranges of 180-250 ˚C for 0.5-72 hours to produce a carbon-rich hydrochar and process water as a byproduct. The hydrochar produced has many applications such as use as solid fuel, catalyst material, fetiliser and process water as a liquid fertiliser or used in the anaerobic digestion (AD) process.
Mathematical modelling in Microsoft Excel is used to create a model for the HTC process flows using data from an existing biogas plant in Vaasa, Finland to determine the mass and energy balances. The cost analysis is based on this model, with literature values, pilot plants and assumptions are used as supportive data. Two locations in the downstream of the AD process are selected, giving two types of sewage sludge digestate as feedstock, 5% ds and 10% ds respectively and a total of six scenarios, three for each feedstock type.
Both cases analysed showed potential for reduced operational costs compared to the current digestate handling costs depending on scenario. However the turnover from the sale of hydrochar is much lower compared to the sale of the compost as currently done. The price for the process water as a liquid fertiliser is inconclusive as there was no clear data for such. The choice of process flow would heavily depend on what is aimed to be achieved with the HTC plant. Is it to produce hydrochar and its byproducts for other purposes or a cost-effective measure for sewage sludge digestate handling and biogas production improvement? One challenge faced in this study was determing the energy balance as literature values found were given as specific energy demand for the whole HTC system and made it challenging to analyse the system in parts for the six scenarios.
The focus in the HTC studies should shift more towards application-specific process parameters and feedstocks for optimal benefits, as these factors easily impact the characteristics of the HTC products and process flow designs
Synthesis attempt of a novel β-O-4’ lignin model compound and the study of a thiourea-based lignin fractionation process using a β-O-4’ lignin model compound
No full textThis thesis work has focused on the synthesis attempt of two novel lignin β-O-4’ model compounds and the study of a lignin fractionation process, using a β-O-4’ model compound.
At first, the synthesis of a β-O-4’ model compound based on acetovanillone and conidendrin was attempted. Acetovanillone contains an alcohol, which needs to be protected to stop it from partaking in competing reactions. The protecting group increased the bulkiness of the acetovanillone derivative. The overall bulkiness of the acetovanillone derivative and conidendrin seemed to hinder the wanted coupling reaction from happening. This hypothesis was studied by changing conidendrin to vanillin. When vanillin was used, the coupling reaction seemed to work. Therefore, it was concluded that the reactants had been too bulky for the coupling reaction to happen.
Next, acetovanillone was changed to 3,4-dimethoxyacetophenone, which does not contain any alcohols and, therefore, removes the need for protection. With the 3,4 dimethoxyacetophenone derivative, the coupling reaction with conidendrin was successful. The last step in the model compound synthesis was a reduction of ketones and esters into diols. The reduction was attempted, however, due to time restrictions the completion could not be verified. There are, however, indications that the reduction might have worked.
The second subject of this thesis work was the study of a thiourea containing lignin fractionation process. A β-O-4’ model compound with alcohols at the α- and γ-positions was used to the study the effects of thiourea in the lignin fractionation process. The lignin fractionation process was imitated with and without the addition of thiourea. The thiourea was discovered to affect the reaction. Therefore, the process was repeated with thiourea in a larger scale. The crude product was purified by flash chromatography three times, and several pure and impure fractions could be separated. All fractions were analysed with 1D NMR, 2D NMR and GC-MS.
Based on NMR, it seemed as if the carbon skeleton remained intact in all pure fractions. In most fractions, clear correlations from the β-O-4’ linkage could be found, meaning that the linkage had not been cleaved. However, significant changes in the shifts of the α-, β- and γ protons could be seen. Since the carbon skeleton was intact, it was concluded that the substituents at the α- and γ-position must have changed to cause the changes in the shifts of the protons. However, due to the nature of the heteroatoms to exchange their protons with the deuterated solvents, there were rarely any evidence about these substituents on NMR.
The product fractions were also analysed with GC-MS. Before the GC-MS analysis, the samples were silylated to improve the volatility of the possible products. Due to the lack of structural evidence about the α- and γ-substituents from NMR, the interpretation of the GC MS data is largely speculative. However, several ions could be identified and fitting fragmentation patters could be solved. Based on the GC-MS data, it seemed as if the thiourea had substituted the α- and γ-alcohols in some fractions. Therefore, it can be concluded that it seems as if thiourea can cause changes at the α- and γ-positions under the used reaction conditions. However, the cleaving of the β-O-4’ linkage could not be seen in any of the fractions
Idyll som skapas och bryts : Skildrandet av natur, idyll och hot i Ulla-Lena Lundbergs Is
No full textDen här avhandlingen analyserar skildrandet av hur idyll skapas och bryts i Ulla-Lena Lundbergs roman Is. Syftet är att synliggöra vilka faktorer som bidrar till att omgivningen framställs som idyllisk och att samtidigt analysera på vilka sätt idyllen bryts. Jag använder mig av ekokritisk forskning om idyll och idyllbrytning i kombination med forskning om skärgårdsromaner och östudier för att diskutera mina frågeställningar.
Analysen visar att idyllen utgörs av en romantiserad föreställning om natur och människor. Den kollektiva gemenskapen och folkets vänlighet och gästfrihet i skärgården betraktas som en av de största orsakerna till att livet på ön upplevs som en lycklig och fridfull tillvaro. Även familjelivet, äktenskapet och viljan att leva enligt naturens rytm bidrar till en idyllisk stämning. Idyllen skapas med andra ord genom en stark samhörighet med platsen. Denna känsla av samhörighet gör att öborna vill stanna kvar på ön, trots de faror och hot som existerar.
Idyllen bryts av faktorer som innebär både inre och yttre hot. I det lilla kollektivet finns konflikter som bevarats i generationer och utöver det förekommer skvaller bland öborna. Naturen och vädret i skärgården är utmanande, vilket bland annat orsakar svårigheter att färdas till eller från ön och därmed utsätts skärgårdsborna för isolering. Naturen, särskilt isen, innebär ett direkt hot mot liv och samtidigt fungerar den som ett hot mot familje- och äktenskapsidyllen
Impacts of a paternity leave reform : Exploring seasonality and heterogeneity in fathers' take-up of parental leave
No full textWhy do family policies not appear to result in greater gender equality in the labour market? We consider a Finnish paternity leave reform that made the use of paternity leave more flexible but did not increase the number of earmarked days. Using this reform as a natural experiment, we explore its effects on fathers’ leave take-up and labour market outcomes for parents. We also study couples’ heterogeneity and whether certain types of couples are more responsive to the reform. We find that fathers whose children were born just after the reform are more likely to take longer paternity leave compared to fathers whose children were born just before the reform. Furthermore, this responsiveness is milder in couples with a large potential gender wage gap. However, no effect is observed in the outcomes measuring gender inequality in the labour market. We show that fathers prefer to utilise their parental leaves during holiday periods, such as the summer months and the end of the year. This behaviour might explain the zero effects of paternity leave reforms on the labour market.nonPeerReviewe
Multifaceted Conscription : A Comparative Study of Six European Countries
No full textAlthough the last few decades have witnessed a shift from conscription to all-volunteer forces in many European countries, recent changes in the European security environment have raised new concerns and prompted several countries to reconsider conscription. However, modern conscription systems have also had to adapt to changing societies and an increasing emphasis on individualistic and neoliberal values. This study aims to examine the various forms of military conscription and illuminate the continuing viability of the conscription model in six European countries: Estonia, Finland, Lithuania, Norway, Sweden, and Switzerland. Four of these countries have consistently maintained conscription (Estonia, Finland, Norway, and Switzerland), while Lithuania and Sweden have recently reinstated conscription. Although conscription systems differ among these countries, there is overall an increasing emphasis on conscript motivation and female participation. Three key aspects are identified to describe different conscription systems: the proportion of conscripted individuals in the birth cohort, motivation to serve, and the approach to female conscripts. Combining these aspects, the study identifies three types of conscription system in these six countries. This article demonstrates that conscription has evolved and adapted to changing societies and security situations instead of merely retaining its traditional form
Effectiveness of an Expendable Unmanned Ground Vehicle Stalling a Mechanized Infantry Company's Primary Combat Units : A Virtual Simulation Experiment
No full textTechnological advancements have spurred the development of unmanned ground vehicles (UGVs) and their innovative militaryapplications and strategies. Such applications include expendable UGVs. However, public research concerning expendablemilitary UGVs remains sparse. Particularly, the unclassified literature does not contain studies regarding their capabilities andeffectiveness in combat. This study introduces a new low‐cost expendable UGV called Laykka. Moreover, the study presents avirtual simulation experiment to evaluate Laykkas' operational capabilities and their impact on advancing mechanized infantryunits. The experiment involved armored reserve officer students assuming the roles of infantry troops forming an attackingopposing force while staff officers controlled simulated infantry troops operating the UGVs. A total of 16 battle simulations werefought. The simulated UGVs operated by a single soldier were able to stall the advancement of the mechanized infantrycompany's primary combat units three times out of four and a smaller force 11 out of 12 times. The best stalling effect wasobserved using a mix of UGVs with different module types. These modules allowed reconnaissance, loitering mine, and anti‐tank operations. The simulation experiment revealed that the UGV was an effective defensive tool due to its self‐destructivecapability, causing marked battle damage, disruption, and confusion to the opposing forces
Connecting Critical Infrastructure Operators and Law Enforcement Agencies to Share Cyber Incident Information with Early Warning Systems
No full textCyber incidents and business interruptions rank as the foremost business risks. With Early Warning Systems (EWS), that work in parallel with other cyber mechanisms, organisations can independently manage cyber sensitive intelligence-related data. This article provides a qualitative multi-case study analysis. The data consists of systematic reviews and cross-case conclusions of six (n = 6) case studies on information sharing. EWS is a valuable tool that can help critical infrastructure providers protect against cyberattacks. EWS can provide a platform for sharing information and resources. This can help improve situational awareness, enhance incident response, and facilitate collaboration. between critical infrastructure providers, as critical infrastructure operators and relevant Law Enforcement Agencies (LEA) can share information on cyber incidents and monitor cyber incident progress. EWS can be used to exchange cyber threat intelligence and information sharing can be facilitated with a common reference library where alerts can be shared as tickets. This would enable information exchange in both directions
Physical Fitness Determinants of a Military Casualty Evacuation Test
No full textIntroduction Casualty evacuation has been identified as a typical and essential single military task which every soldier should be able to perform rapidly during combat. Previous studies suggest that casualty evacuation is typically conducted by dragging and demands e.g., lean body mass and anaerobic performance. Association of physical fitness with casualty evacuation by dragging has been studied widely but previous studies lack comprehensive assessment of all physical fitness determinants. The purpose of the present study was to examine comprehensively how casualty emergency evacuation (CEE) performance associates with physical fitness and body composition.
Materials and Methods A total of 25 conscripts (20 men, 5 women) volunteered for measurements of height, weight, waist circumference, body composition, 1-min sit-ups and push-ups, grip strength, isometric bench and leg press, standing long jump, 30-s cycle ergometer test, and 12-min run test. Subjects performed a CEE test in which evacuation time (ET), heart rate, blood lactate concentration, and rate of perceived exertion were measured. In the CEE test, subjects wore combat gear (11.7 ± 1.6 kg) and dragged a doll wearing combat gear (80.2 kg) 28 m while crawling (go round two cones, Z-pattern) and 20 m upright (straightforward). Correlations and backward regression analysis were used for statistical analyses. The level of significance was set to P ≤ .05.
Results Evacuation time lasted on average 87 ± 32 s with a peak heart rate of 184 ± 6 bpm, lactate concentration of 9.4 ± 2.7 mmol/l, and RPE of 17 ± 1. Evacuation time correlated inversely and strongly with anaerobic capacity and power (r = −0.72-0.78, P ≤ .001), but not with aerobic fitness. Inverse and strong correlations were observed between ET and maximal strength variables (r = −0.58-0.69, P ≤ .01), whereas muscular endurance and ET revealed non-significant correlations. Evacuation time correlated moderate to strongly with body fat percentage (r = 0.48, P ≤ .05) and inversely with lean body mass (r = −0.74, P ≤ .001) and body height (r = −0.53, P ≤ .01). The backward regression analysis showed that anaerobic capacity (standardized β = −0.52, P ≤ .001), fat percentage (standardized β = 0.40, P ≤ .001), and isometric leg press (standardized β = −0.25, P ≤ .1) together explained the variance of ET significantly (adjusted R2 = 0.84, P ≤ .001).
Conclusions This study examined thoroughly how different physical fitness dimensions and body composition relate to a CEE test performed by a combination of dragging while crawling and in upright position. Casualty emergency evacuation was discovered as a high-intensity military task, which demands most importantly high anaerobic performance, lean body mass, and maximal strength capabilities. Improving these dimensions of physical fitness should be considered highly important as CEE is essential and possibly one of the most demanding military tasks which every soldier should be able to conduct in combat. From operational perspective, it is relevant that soldiers are able to perform CEE during operations; therefore, further research is needed on how acute operational stress changes the nature of CEE and its physical determinants
Human Factors Issues of Limited Connectivity in Advanced UAS Operations : Insights and Prospects
No full textThis paper presents an assessment of relevant human factors issues of advanced unmanned aircraft systems (UAS), which are affected by limited data connectivity. Based on an earlier literature review, we categorize these issues under three aspects, namely system design, human factors evaluation, and operation process. Under each aspect, we examine in detail the pertinent human factors engineering insights regarding unmanned aircraft systems and their connectivity. We also present prospects for future research by listing relevant human factors-related research questions for each aspect regarding limited connectivity in UAS operations. A key conclusion of the paper is that similar human factors issues, such as automation awareness and trust, apply for advanced UAS operations as they do to other well-studied automated safety-critical environments.ei tietoa saavutettavuudest
Exploring crisis management response to hybrid threats and warfare
No full textCrisis management (CM) operations and organisations may face internal, external and hybrid threats (HTs) against their information and/or personnel. This research looks at how selected European Union (EU), North Atlantic Treaty Organization (NATO) and national perspectives address internal, external and global HTs and influence, even warfare, and maps some relevant strategies to prepare against them in a CM context. Strategies to fight against HTs include relevant political debate and decision-making, integration of EU- and national-level security into critical infrastructure and regular preparedness exercises. Responses to HTs call for relevant technical, situational awareness and problem-solving skills. This research shows how collaboration and situation understanding can assist in detecting and responding to possible cyber and HTs against CM operations. This study examines how collaboration and understanding the situation assist in detecting and responding to HTs to CM operations. There is evidence that information exchange and collaboration are important elements in the fight against hybrid influence and war. Combating misinformation through public education campaigns can support both the civilian and military elements of CM operations. Specific training can be designed to counter aggressive propaganda and disinformation efforts against personnel in CM operations. This maintains one’s initiative and trust in the aims of the mission.ei tietoa saavutettavuudest