Cyanobacteria belong to the oldest organisms of our planet. They use photosynthesis to produce ATP and gain biomass from carbon dioxide. The cyanobacteria Nostoc punctiforme is a filamentous bacterium that consists of two different types of cells, vegetative cells and heterocysts. The type of cell it differentiates into depends on the media they grow in. In an ammonium-rich medium, the N.punctiforme consists of vegetative cells that differentiate into heterocysts when in the medium is changed to a low-concentration ammonium medium. The ammonium-binding nitrogenase in the heterocysts does not work in an oxidative environment. During oxidative stress, N.punctiforme produces Dps (DNA binding protein from starved cells) which protects DNA. In the heterocysts the nitrogenase produces hydrogen as a side product. The hypothesis is that Dps is cell specific. In order to study this protein, a fusion of the promotor of Dps and GFP (Green Flourescent Protein) was constructed. To detect GFP, optimization of a Western Blot (WB) for GFP was performed. Protein samples were analyzed in strains of N.punctiforme. In strain 12A, the production of GFP was visualized but the band was not specific. Several attempts of optimization of the WB procedure were performed, but none of them showed clear specific protein detection in the N.punctiforme strains. Further optimization of the WB protocol is needed.

Norska pappersmassaindustrin Norske Skog Saugbrugs AS använder flera olika biobränslen i en bränslemix vid produktion av ånga för internt bruk. Biobränslen visar stora variationer i asksammansättning och producerad askmängd, varför syftet var att studera dessa i förhållande till bränslemixen, via en statistisk analys av Saugbrugs befintliga data. Rökgaserna från förbränningen renas med ett elektrofilter med tre avskiljningsfält för askstoftet, och en teori om fraktionering av aska från de olika fälten vad gäller innehåll av ekotoxiska metaller fanns. Provtagning, analys av partikelstorlek och laboratorieanalys av askstoft i rökgasen samt aska avskilt av de olika fälten i elektrofiltret var därför motiverat. Förbränningen som helhet alstrar stora mängder aska som sedan deponeras. En undersökning av alternativa användningsområden i enlighet med myndighetskrav för aska gjordes baserat på resultaten från den statistiska analysen och de fyra provuttagningarna. Att statistiskt sammanföra bränslena i en varierande bränslemix med asksammansättning gav litet resultat, men bekräftade att stora variationer finns. Askmängden varierade till följd av vilka bränslen som eldades, snarare än mängden bränsle. Det ackrediterade laboratoriet hade använt sig av två olika analysmetoder vars resultat visade olika koncentrationer för vissa ämnen. Multivariat dataanalys tyder på att koncentrationerna var likvärdiga mellan den gamla och den nya metoden, därmed berodde koncentrationsförändringen inte på Saugbrugs förbränning eller bränslemix. Den befintliga askan innehåller höga koncentrationer av arsenik, bly och krom, och är inte direkt lämplig för alternativ användning. Innehållet av ekotoxiska metaller beror troligtvis främst på förbränning av RT-flis, men till viss del även slam och eget avfall. Mikroskopisk analys av askproven visar att partikelstorleken minskar ju längre in i rökgasreningen askstoftet kommer, och kemisk analys visar en tydlig fraktionering mellan de olika fälten där halten ekotoxiska metaller ökar med minskande partikelstorlek. Askan i de två sista fälten innehåller kritiska koncentrationer av ekotoxiska metaller. Askan uppfyller därmed inte myndighetskrav för skogsspridning eller liknande, och särskilt arsenikkoncentrationen är mycket hög. Saugbrugs aska måste fraktioneras eller behandlas om den skall användas. Fraktionering av aska för olika ändamål kan vara möjligt, men variationer kan förekomma och bör beaktas. Lämpligast vid alternativ användning är att späda askan eller en askfraktion med en annan aska, eller kalk. / The Norwegian paper pulp industry Norske Skog Saugbrugs AS combusts a variety of biofuels in a fuel mix, producing steam for internal use. Biomass is often associated with large variations in ash composition and produced ash quantity, thus the aim was to study these in relation to the used fuel mix through a statistical analysis of Saugbrugs existing data. Flue gases from the combustion are purified with an electrostatic precipitator (ESP), which consists of three fields for ash trapping. Other studies have shown that fractionation of ash from the different fields regarding the content of ecotoxical metals is possible; therefore the study also included sampling, particle size analysis and chemical analysis of samples from ash in the flue gas and ash from the three fields in the ESP respectively. The combustion produces large amounts of ash which is landfilled. An investigation of alternative uses in accordance with regulations for ash was made based on results from the statistical analysis and the four ash samples. The statistical analysis of the fuel mix in relation to the ash composition yielded little results, but showed that large variations exist. The produced ash quantity also varied due to the type of fuel used, rather than how much fuel is combusted. The existing data was based on different analytical methods at the accredited laboratory resulting in different substance concentrations. With multivariate analysis it was concluded that the different concentrations are equivalent between the old and the new method, thus the change is not due to Saugbrugs combustion or fuel mix. The ash contains high concentrations of arsenic, lead and chrome, and is not directly suitable for alternative use. The content of ecotoxic metals in the ash is mainly due to combustion of demolition wood, but also to sludge and waste in some extent. Analysis of the samples show that particle size decreases as the ash moves further in the flue gas purification process, and a distinct fractionation between the different fields where the content of ecotoxic metals increase with decreasing particle size. The ash collected in the two last fields therefore contains critical concentrations of ecotoxic metals. The ash does not meet the requirements regarding forest spreading or similar, and the concentration of arsenic is particularly high. Saugbrugs ash must be fractionated or treated if it is to be used alternatively. Fractionation of ash for various purposes might be possible, although variations may occur and must be considered. The most suitable approach is to dilute the ash or ash fraction with another ash, or lime.

The risk of food insecurity in the form of higher food prices has prompted policymakers in the United States (US) and European Union (EU) to revise their approach to biofuel development. The US Renewable Fuel Standard (RFS) and EU Directive 2009/28/EC require long term use of renewable energy in transportation, subject to sustainability. This thesis examines the implications of the US RFS and EU Directive 2009/28/EC in a trade context using a partial equilibrium/comparative static framework. The focus is on the effect of the revised biofuels policies on opportunities for developing countries to supply the US and/or EU markets. For the US, the implications when the volume produced and/or required under the RFS is technologically infeasible with imports of ethanol as a potential policy alternative are explored. For the EU, the impact of the sustainability criteria on foreign biodiesel suppliers in terms of compliance cost is examined. In general, the US policy may enhance opportunities for trade while the EU policy will likely inhibit trade. A discussion of the implications of the mandates for developing countries and WTO is included.

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Introduction: The index of new cars’ climate impact (Trafikverket 2010) calculated a reduction factor to quantify the positive impact of renewable fuels on CO2 emissions for new cars in Sweden 2009. Although uncertainty for many input parameters is acknowledged, all calculations were made with point estimates. Aim: The aim of this study was to verify consumer recommendations based on carbon dioxide emissions of new cars by re-assessing the CO2 emissions considering the uncertainty in input data. The data uncertainty was quantified by using probabilistic risk assessment methodology. The objectives were (1) to calculate the possible reduction of CO2 emissions for new cars in Sweden accounting for uncertainties; (2) to identify the most influential factors by conducting a sensitivity analysis; and (3) to assess the implications of interval analysis and probabilistic modelling for epistemic uncertainty in this context and thereby to contribute to the discussion on which method is the most appropriate to support decision making. Method: Calculations were performed with the deterministic model proposed by Trafikverket (2010) using probability distributions (Bayesian probability distributions assigned by expert judgements) and intervals as model input. Probabilistic modelling was implemented as Monte Carlo simulation with uniform distributions and triangular distributions in Matlab. Interval calculations were done by hand. Results: The best estimate from probabilistic modelling of CO2 reduction when using E85 as a fuel of 30% (95% confidence interval = 10% to 52%) is in a similar range as the 20% given by Trafikverket (2010). The best estimate of 28% decrease for gas cars (95% confidence interval = 3% to 44%) is lower than the originally proposed 42%, but still in a similar range. The difference is due to the large extent of optimistic values taken by Trafikverket (2010). The interval analysis produced a wider range. For ethanol driven cars, a CO2 reduction of 68%, an increase of 14% or anything in between is calculated, for cars operated on gas the result is a CO2 reduction of 59%, an increase of 29% or anything in between. Conclusions: The use of biofuels most likely reduces CO2 emissions. The CO2 emissions from the production of the biofuel are the most influential factors. The recommendations of Trafikverket to the consumers are still valid after probabilistic recalculation. Probabilistic modelling is more appropriate than interval analysis to guide authority and consumer decisions as it allows conclusions to be drawn and therefore can support decision making.

The increase of petroleum cost as well as global warming and climate change result in investigation to discover new renewable energy resources. Bioenergy is one of the most important sources that is concerning the scientists and industrial sector. Although bioethanol had to be known as one of the most important renewable energy sources in order to reduce greenhouse gases and global warming, there is a limited number of publications reporting on them. In this review, a brief overview is offered about bioethanol production from algae. It can be given a deeper insight in dificulties and promising potential of bioethanol from algae. / Sự gia tăng giá nhiên liệu hóa thạch cùng với cảnh báo toàn cầu về biến đổi khí hậu hướng đến việc nghiên cứu tìm ra những nguồn năng lượng có thể tái tạo. Năng lượng sinh học là một trong những nguồn quan trọng được các nhà khoa học và doanh nghiệp quan tâm. Mặc dù ethanol sinh học đã được biết đến như là một trong những dạng năng lượng tái tạo quan trọng nhất để giảm thiểu các khí nhà kính và cảnh báo toàn cầu, nhưng chỉ có một số ít bài báo về nó. Trong bài tổng quan này, chúng tôi giới thiệu vắn tắt việc sản xuất ethanol sinh học từ tảo. Nó đưa ra cái nhìn sâu hơn về những khó khăn và tiềm năng hứa hẹn của sản xuất ethanol sinh học từ tảo.

This work focused upon design and operation of biodiesel production facilities in support of the broader goal of developing a strategic approach to the development of biorefineries. Biodiesel production provided an appropriate starting point for these efforts. The work was segregated into two stages. Various feedstocks may be utilized to produce biodiesel, to include virgin vegetable oils and waste cooking oil. With changing prices, supply, and demand of feedstocks, a need exists to consider various feedstock options. The objective of the first stage was to develop a systematic procedure for scheduling and operation of flexible biodiesel plants accommodating a variety of feedstocks. This work employed a holistic approach and combination of process simulation, synthesis, and integration techniques to provide: process simulation of a biodiesel plant for various feedstocks, integration of energy and mass resources, optimization of process design and scheduling, and techno-economic assessment and sensitivity analysis of proposed schemes. An optimization formulation was developed to determine scheduling and operation for various feedstocks and a case study solved to illustrate the merits of the devised procedure. With increasing attention to the environmental impact of discharging greenhouse gases (GHGs), there has been growing public pressure to reduce the carbon footprint associated with fossil fuel use. In this context, one key strategy is substitution of fossil fuels with biofuels such as biodiesel. Design of biodiesel plants has traditionally been conducted based on technical and economic criteria. GHG policies have the potential to significantly alter design of these facilities, selection of feedstocks, and scheduling of multiple feedstocks. The objective of the second stage was to develop a systematic approach to design and scheduling of biodiesel production processes while accounting for the effect of GHG policies. An optimization formulation was developed to maximize profit of the process subject to flowsheet synthesis and performance modeling equations. The carbon footprint is accounted for through a life cycle analysis (LCA). The objective function includes a term reflecting the impact of the LCA of a feedstock and its processing to biodiesel. A multiperiod approach was used and a case study solved with several scenarios of feedstocks and GHG policies.

This thesis work describes the formulation of a Bayesian approach along with new tools to systematically reduce uncertainty in Research&Development (R&D) alternatives. During the initial stages of R&D many alternatives are considered and high uncertainty exists for all the alternatives. The ideal approach in addressing the many R&D alternatives is to find the one alternative which is stochastically dominant i.e. the alternative which is better in all possible scenarios of uncertainty. Often a stochastically dominant alternative does not exist. This leaves the R&D manager with two alternatives, either to make a selection based on user defined utility function or to gather more information in order to reduce uncertainty in the various alternatives. From the decision makers perspective the second alternative has more intrinsic value, since reduction of uncertainty will improve the confidence in the selection and further reduce the high downside risk involved with the decisions made under high uncertainty. The motivation for this work is derived from our preliminary work on the evaluation of biorefiney alternatives, which brought into limelight the key challenges and opportunities in the evaluation of R&D alternatives. The primary challenge in the evaluation of many R&D alternatives was the presence of uncertainty in the many unit operations within each and every alternative. Additionally, limited or non-existent experimental data made it infeasible to quantify the uncertainty and lead to inability to develop an even simple systematic strategy to reduce it. Moreover, even if the uncertainty could be quantified, the traditional approaches (scenario analysis or stochastic analysis), lacked the ability to evaluate the key group of uncertainty contributors. Lastly, the traditional design of experiment approaches focus towards reduction in uncertainty in the parameter estimates of the model, whereas what is required is a design of experiment approach which focuses on the decision (selection of the key alternative). In order to tackle all the above mentioned challenges a Bayesian framework along with two new tools is proposed. The Bayesian framework consists of three main steps: a. Quantification of uncertainty b. Evaluation of key uncertainty contributors c. Design of experiment strategies, focussed on decision making rather than the traditional parameter uncertainty reduction To quantify technical uncertainty using expert knowledge, existing elicitation methods in the literature (outside chemical engineering domain) are used. To illustrate the importance of quantifying technical uncertainty, a bio-refinery case study is considered. The case study is an alternative for producing ethanol as a value added product in a Kraft mill producing pulp from softwood. To produce ethanol, a hot water pre-extraction of hemi-cellulose is considered, prior to the pulping stage. Using this case study, the methodology to quantify technical uncertainty using experts' knowledge is demonstrated. To limit the cost of R&D investment for selection or rejection of an R&D alternative, it is essential to evaluate the key uncertainty contributors. Global sensitivity analysis (GSA) is a tool which can be used to evaluate the key uncertainties. But quite often global sensitivity analysis fails to differentiate between the uncertainties and assigns them equal global sensitivity index. To counter this failing of GSA, a new method conditional global sensitivity (c-GSA) is presented, which is able to differentiate between the uncertainties even when GSA fails to do so. To demonstrate the value of c-GSA many small examples are presented. The third and the last key method in the Bayesian framework is the decision oriented design of experiment. Traditional 'Design of Experiment' (DOE) approaches focus on minimization of parameter error variance. In this work, a new "decision-oriented" DOE approach is proposed that takes into account how the generated data, and subsequently, the model developed based on them will be used in decision making. By doing so, the parameter variances get distributed in a manner such that its adverse impact on the targeted decision making is minimal. Results show that the new decision-oriented DOE approach significantly outperforms the standard D-optimal design approach. The new design method should be a valuable tool when experiments are conducted for the purpose of making R&D decisions. Finally, to demonstrate the importance of the overall Bayesian framework a bio-refinery case study is considered. The case study consists of the alternative to introduce a hemi-cellulose pre-extraction stage prior to pulping in a thermo-mechanical pulp mill. Application of the Bayesian framework to address this alternative, results in significant improvement in the prediction of the true potential value of the alternative.

The major goals of this thesis were to (1) design and synthesize a supported catalyst with well-defined monodisperse palladium nanoparticles evenly distributed throughout an inorganic oxide substrate with tunable porosity characteristics, (2) demonstrate the catalytic activity of this material in the decarboxylation of long chain fatty acids and their derivatives to make diesel-length hydrocarbons, (3) elucidate the deactivation mechanism of supported palladium catalysts under decarboxylation conditions via post mortem catalyst characterization and develop a regeneration methodology thereupon, and (4) apply this catalytic system to a real low-value biofeedstock. In an effort to maximize loading and minimize mass transfer limitations, mesoporous silica MCF was synthesized as catalyst support. Functionalization with various silane ligands facilitated even distribution of palladium precursor salts throughout the catalyst particle, and, after reduction, monodisperse palladium nanoparticles approximately 2 nm in diameter. The Pd-MCF catalyst showed high one-time activity in the decarboxylation of fatty acids to hydrocarbons in dodecane at 300 °C. Subsequent reactions were performed on acid derivatives to elucidate a decarboxylation reaction pathway. The catalyst experienced severe deactivation after only one use and substantial effort was put into elucidating the nature of this deactivation via post mortem catalyst characterization. The deactivation was found not to be caused by nanoparticle sintering, agglomeration or ripening, but instead by organic deposition, mainly of reactant acid. A regeneration methodology was developed and subsequent catalyst reuse exhibited high activity. Finally, the Pd-MCF catalyst was applied to a wastewater-derived brown grease from a poultry rendering facility, in an unpolished and polished form. The latter was successfully decarboxylated to diesel-length hydrocarbons with high conversion and selectivity.

An innovative wastewater treatment technology was developed to recover renewable resources, such as water, energy and nutrients, from sewage. First, a novel synthetic sewage was evaluated for its suitability to serve as an alternative substrate for lab-scale wastewater treatment (WWT) research. Based on granular dried cat food, Complex Organic Particulate Artificial Sewage (COPAS) is a commercially-available, flexible, and easy to preserve feed. Characteristics of COPAS, namely chemical composition, disintegration/dissolution kinetics, and anaerobic biodegradability, were determined. Anaerobic bioassays indicate that COPAS is highly biodegradable at the concentration used to simulate household sewage (1000 mg/L), with more than 72% of the theoretical methane content reached after 30 d of incubation. Results indicate that COPAS is a suitable substrate as a surrogate of domestic sewage. In the second stage of the research, a lab-scale, 10L gas-lift anaerobic membrane bioreactor (Gl-AnMBR) was designed, fabricated and tested. The AnMBR is a hybrid treatment technology that combines anaerobic biological treatment with low-pressure membrane filtration. Although AnMBR has been used in many instances for the treatment of high strength industrial or agricultural wastewater, relatively little has been reported about its application for the treatment of domestic sewage and further conversion and recovery of resources embedded in sewage, such as energy and nutrient enriched water. The 10L column reactor uses a tubular PVDF ultrafiltration membrane (with biogas as sparge gas) for sludge/water separation. COPAS was used as synthetic feed (at 1000 mg/L) to represent household wastewater. The configuration showed excellent removal efficiencies of organic matter (up to 98% and 95% in COD and TOC removal, respectively) while producing energy in the form of methane at quantities suitable for maintaining membrane scrubbing (4.5 L/d of biogas). Soluble nutrients were recovered in the effluent in the forms of NH4, (9.1±4.2 mg/L), NO3 (2.2±0.9 mg/L) and PO4 (20±7.13 mg/L). The energy footprint (net energy) of this reactor was evaluated and the energy requirements per volume of permeate produced was found to be in the range of -1.2 to 0.7 kWh/m3, depending on final conversion of methane to electric or thermal energy respectively. These values could potentially be improved towards energy surplus (-2.3 to -0.5 kWh/m3) if applied to plant scale operation, which would employ more efficient pumps than those used in the lab. Results from this study suggest that the Gl-AnMBR can be applied as a sustainable treatment tool for resource recovery from sewage, which can further be optimized for large scale operation. In the final stage of this research, further resource recovery from sewage was investigated by coupling the Gl-AnMBR with an innovative gas-lift algal photo MBR (APMBR). To our knowledge, this is the first reported application of membranes (in particular gas-lift tubular) for separation of algal cells from effluent in a continuous-flow photobioreactor. Nutrient rich effluent (9 mg/L NH4-N and 20 mg/L PO4-P) from the Gl-AnMBR treating domestic wastewater was used as substrate to grow the biofuel producing microalgae Chlorella sorokiniana (Cs). The initial set of operational conditions tested in this study (HRT of 24 hours, operational flux of 4.5 LMH, air-lift flow rate (Qa) of 0.1 L/min and 0.1 bars of membrane inlet pressure), achieved 100% removal efficiencies for NH4 and PO4. Flux remained constant during the experimental period which demonstrated the efficacy of gas lift as a membrane fouling control strategy for an algae bioreactor. Because the algae is photoautotrophic, little removal of organic carbon was expected nor observed. Further studies are required to better understand the fate and cycling of carbon in the APMBR. Limited information is available in the literature regarding biofuel-producing, algal photo MBRs utilizing anaerobic effluents as feedstock, which makes this study an important step in understanding the design and performance of combined anaerobic/algal biotechnology for large scale application of wastewater resource recovery.