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The prevention of emissions of amine species is of high importance for the overall sustainability and performance of Post Combustion CO2 Capture facilities. There is a clear understanding of amine emissions based on volatility in the treated flue gas. Emission via aerosols from Post Combustion CO2 Capture facilities has only been pointed out recently. Thus, there is little knowledge about emission via aerosols in contrast to emission based on volatility. It has been found that flue gas quality plays an important role for emissions caused by aerosols formation. In this work, we study the experimental assessment of the impact of flue gas quality on the level of monoethanolamine (MEA) emission via aerosols. In a dedicated test rig, effects of the flue gas components such as sulphuric acid aerosols and extremely fine particles like soot has been studied. An aerosol generator capable of producing controlled amounts of soot and dosing sulphuric acid aerosol to a mobile CO2 capture mini-plant was used as a test equipment for this study. Soot particle number concentration were in the range of 104-106 per cm3. The particle number concentration for different amount of H2SO4 aerosols were in the order of 108 per cm3. Amine emissions up to 4.3ppmv (12mg/Nm3 for MEA) is considered to be as an upper limit for the design of a Post Combustion CO2 Capture plant. MEA emissions in the presence of soot particles were in the range of 100-200mg/Nm3 which is 2-4 times higher than baseline vapour based emissions of about 45mg/Nm3. The expected particle size of H2SO4 aerosols is well below 100nm, while the corresponding mass concentration range is between 1 and 5mg/m3. The MEA emissions observed due to H2SO4 aerosols were in the range of 600-1100mg/Nm3. Moreover, parametric tests have shown that besides flue gas quality, the absorber temperature profile and the presence of CO2 in the flue gas are pre-requisite for aerosol emissions. It is evident that the observed level of emissions in this study are unacceptable. Therefore, it is imperative that fundamental know-how about aerosol formation and reduction is generated in order to design appropriate counter measures. © 2013 Elsevier Ltd.

Horizontal smooth and microfinned copper tubes with an approximate diameter of 9 mm were successively flattened in order to determine changes in flow field characteristics as a round tube is altered into a flattened tube profile. Refrigerants R134a and R410A were investigated over a mass flux range from 75 to 400 kg m−2 s−1 and a quality range from approximately 10–80%. For a given refrigerant mass flow rate, the results show that a significant reduction in refrigerant charge is possible. Pressure drop results show increases of pressure drop at a given mass flux and quality as a tube profile is flattened. Heat transfer results indicate enhancement of the condensation heat transfer coefficient as a tube is flattened. Flattened tubes with an 18° helix angle displayed the highest heat transfer coefficients. Smooth tubes and axial microfin tubes displayed similar levels of heat transfer enhancement. Heat transfer enhancement is dependent on the mass flux, quality and tube profile.

Abstract Gasification of biomass and fossil fuels, hot gas cleanup using a ceramic filter and combustion of LCV product gas in a combustor were performed using a 1.5 MWth test rig (pressurised bubbling fluidised bed gasifier) at Delft University and a 10– 50 kWth system at Stuttgart University (DWSA) in the framework of experimental research on efficient, environmentally acceptable large-scale power generators based on fluidised bed gasification. The influence of operating conditions (pressure, temperature, stoichiometric ratio) on gasification (gas composition, conversion grades) was studied. The gasifiers were operated in a pressure range of 0.15– 0.7 MPa and maximum temperatures of ca. 900°C. The Delft gasifier has a 2 m high bed zone (diameter: 0.4 m ) followed by a freeboard approximately 4 m high (diameter: 0.5 m ). The IVD gasifier has a diameter of 0.1 m and a reactor length of 4 m . Carbon conversions during wood, miscanthus and brown coal gasification experiments were well above 80%. Fuel-nitrogen conversion to ammonia was above ca. 50% and the highest values were observed for biomass. The results are in line with other investigations with biomass bottom feeding. Deviation occurs compared with top feeding. Measurements are compared with simulation results of a reaction-kinetics-based model, using ASPEN PLUS, related to emission of components like fuel-nitrogen-derived species. Data from literature regarding initial biomass flash pyrolysis in the gasification process are used in the gasifier model and will be compared with simulation results from the FG-DVC model. Measurements and model predictions were in reasonably good agreement with each other.

High Density Plasma (HDP) reactors are currently introduced for the deposition of SiO/sub 2/ and SiOF in submicron gaps between aluminium conductors in advanced integrated circuits. The main feature of HDP reactors is the ability to fill high aspect ratio spaces between aluminium conductors. This feature is achieved by employing a simultaneous deposition and sputtering process.

As a preliminary step to evaluating the acute neurobehavioral effects of hydrocarbon solvents and to establish a working model for extrapolating animal test data to humans, joint neurobehavioral/toxicokinetic studies were conducted which involved administering ethanol to rats and volunteers. The specific objectives of the present studies were to evaluate the acute central nervous system (CNS) effects of ethanol in rats and humans and to assess relationships between internal levels of exposure and behavioral effects. A more general objective was to validate a battery of neurobehavioral tests that could be used to carry out comparative studies in both species. Accordingly, a range of tests including standardized observational measures, spontaneous motor activity assessments and learned visual discrimination performance was utilized in rat studies to evaluate acute CNS effects. Groups of rats were given ethanol at levels of approximately 0.5, 1.0 or 2.0g/kg, with blood level measurements to verify internal doses. In a volunteer study, 12 healthy male subjects were given 0.65g/kg ethanol, a level approximating the limit for motor vehicle operation in The Netherlands, and neurobehavioral effects were measured prior to and 1 and 3h after ethanol administration, with a computerized neurobehavioral test battery. Blood and air measurements were made to quantify internal doses. Results of the behavioral tests in rats provided evidence of ethanol-induced changes in neuromuscular, sensori-motor, and activity domains. There were also significant changes in visual discrimination, particularly in the areas of general measures of responding and psychomotor speed. In humans there were small but statistically significant effects on learning and memory, psychomotor skills and attention. However, the effects were subtle and not all parameters within given domains were affected. These studies demonstrated a qualitative similarity in response between rats and humans.

Private households constitute a considerable share of Europe's electricity consumption. The current electricity distribution system treats them as effectively passive individual units. In the future, however, users of the electricity grid will be involved more actively in the grid operation and can become part of intelligent networked collaborations. They can then contribute the demand and supply flexibility that they dispose of and, as a result, help to better integrate renewable energy in-feed into the distribution grids. © 2014 IEEE.

This review highlights the challenges of fiscal system optimization considering both the host government and extraction company perspectives. Countries around the world face an arduous task in determining the optimal fiscal system to maximize the capture of economic rents of natural resource extraction activities. The extraction industry is equally challenged to meet global commodity demand because the capital investments required for developing new hydrocarbon fields and ore mines are on the rise, while tax takes on extraction activities tend to rise too in many frontier jurisdictions. Normal profit must remain for the extraction companies, and returns must be large enough to replace for resource depletion. Companies use the benefits of resources produced in one country to finance capital investments for future field development in another country. One viewpoint is that profits are expatriated to the detriment of the host country and to the benefit of another country or the world supply chain as a whole. Another viewpoint is that all resource holders benefit because a foreign entity always starts in a new resource holding nation by investing in the development of an oil field or solid mineral mine using the profits from previous projects in other countries. A key question is What is a fair taxation regime for natural resource extraction in a particular geological setting and a given geographical location, taking into account subsurface uncertainty about the quality and volume of the resource, infrastructure needs and proximity to the world’s major markets and trade centers? Tax distortion could go both ways: either incentivize, attract and stimulate or des-incentivize, repel and deter resource development. Additional factors to consider are external uncertainties such as political and fiscal stability, sovereign risk and even local weather conditions (mostly in offshore and Arctic petroleum operations). Governments must tax the upstream rents of petroleum and mineral resources, but not to the level that suppresses extraction activities. All stakeholders want at least an equitable share of the profits. Defining what is equitable is a matter of intensive negotiations, renegotiation of prior agreements and sometimes litigation and international arbitration. Several case studies, covering both petroleum and solid mineral extraction projects, are included to highlight the key points involved in fiscal policies designed to optimize the utility of geological resource endowments. For example, the offshore tax regime employed in the US pivots the trade-offs between fiscal incentives and long-term resource supply to ensure energy security. This review concludes with a call for further research.

This paper presents a finite element modeling technique for double U-tube borehole heat exchangers (BHE) and the surrounding soil mass. Focus is placed on presenting numerical analyses describing the capability of a BHE model, previously reported, to simulate three-dimensional heat transfer processes in multiple borehole heat exchangers embedded in a multi-layer soil mass, in a computationally efficient manner. Geothermal problems which require very fine meshes, of the order of millions of finite elements, can be simulated using coarse meshes, of the order of a few hundred to a few thousand elements. Accordingly, significant reduction of CPU time is gained, rendering the model suitable for utilization in engineering practice. A validation example comparing computed results with measured results is presented. Parametric analyses are also presented describing the possible utilization of the model for research works and design optimization.