Qatar Foundation Annual Research Forum Volume 2013 Issue 1
- تاريخ المؤتمر: 24-25 Nov 2013
- الموقع: Qatar National Convention Center (QNCC), Doha, Qatar
- رقم المجلد: 2013
- المنشور: ٢٠ نوفمبر ٢٠١٣
281 - 300 of 541 نتائج
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Field testing of membrane distillation for desalination of brines discharge from thermal plants
المؤلفون: Joel Minier MatarMembrane Distillation (MD) is a hybrid thermal-membrane process that produces a high quality distillate from concentrated brine. It utilizes either low grade waste heat or solar energy to generate a vapor pressure difference across a hydrophobic membrane. A consortium composed of ConocoPhillips - Global Water Sustainability Center (GWSC), Qatar University (QU) and Qatar Electricity & Water Company (QEWC), was formed to conduct a pilot testing program to assess the suitability of MD at pilot scale to treat brines from thermal desalination plants. This research project aims toward ensuring a sustainable water supply in Qatar, one of the twelve grand research challenges identified recently by Qatar National Research Strategy (QNRS). This presentation summarizes the outcomes of the project including the most relevant conclusions and findings from the field testing program. Bids from the five leading MD technology providers were evaluated and the two most suitable technologies for Qatar environment were selected: a vacuum multi-effect MD unit from memsys in Germany and a single stage air gap MD unit from Xzero in Sweden. Initially, hydraulic testing was conducted at QU and then the pilots were relocated to the QEWC power/desalination plant at Ras Abu Fontas to operate under field conditions. Globally, this is the first study that benchmark MD technologies side by side at pilot scale. The performance of the MD pilot units was evaluated under different operating conditions (temperature, flowrate and feed salinity up to 70,000 mg/L TDS) with the objective of maximizing water production and lowering operational costs. The product stream was of distilled water quality (TDS < 10 ppm), independent of feed salinity. Typical flux values of 5 - 6 LMH were obtained at feed / cooling temperatures of 70oC / 20oC. Results also showed that pretreatment plays an important role on system performance. An important outcome of the project was related to the energy efficiency of the systems. Detailed energy balance showed that a multi-effect design significantly improves energy efficiency. The multi effect system has a performance ratio of 3.0, which was 3 times higher than the single stage system. The projected outcome of the testing program includes: * Sustainable augmentation of water production in Qatar * Reduction of environmental impact * Capacity building in Qatar
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Zero energy and emission building laboratory Qatar: Experimental study and calorimetric measurements on building envelopes under outdoor exposure
المؤلفون: Armin BaumlerIntelligent building envelopes can significantly reduce the environmental impact of our buildings during their whole life cycle. Intelligent means that user comfort is reached through subtle use of devices to manage indoor climate (temperature, air quality, humidity and light) in the most energy-efficient way while involving outdoor conditions as suitable. A promising methodology consists in keeping the building services as basic and user-friendly as possible without compromizing energy efficiency and minimal environmental impact. This is achieved through active control of the building skin functions, adapting them to the constantly changing outdoor conditions. This approach not only fits to new buildings, but can be implemented as well on existing building stock, for example in the context of a renovation/refurbishment project. Qatar will see intensive building activities taking place in the coming years. A great challenge and opportunity to put the intellectual approach into practice. Since end of 2012, the ZERO ENERGY AND EMISSION BUILDING LABORATORY of Hydro Building Systems GmbH which has been set up at Qatalum can be used for experimental researches on façade systems under natural weathering conditions. The target of the first series of measurement is to analyse the energetic efficiency of four different types of façades. Reference is a SSG façade with insulating double glazing with a g-value of 0.16. Optionally, an external blind can be operated. Further façade types are a SSG façade identical to the reference façade, fitted with a fixed external brise-soleil made up of aluminium blades, a high insulation stick type façade with triple glazing and Venitian blind in the pane interspace as well as a box-type window with turn/tilt sash inside and parallel outward sash outside with a Venetian blind fitted in-between. Calorimetric measurements regarding the required energy needs show that a fixed brise-soleil (blades) reduces the cooling energy requirements by approx. 22%. An external venetian blind offers potential savings of approx. 40%. Replacing a standard stick type façade with double insulating glass by a high insulation façade with coated triple glazing and integrated sun protection, the cooling energy consumption can be reduced by more than 57%. A double skin box-type window solution with sun protection in the interspace cuts the energy consumption for cooling the room by 40%.
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Study of radioactivity levels in the marine environment along the exclusive economic zone (EEZ) of Qatar
المؤلفون: Ilham Al-QaradawiRadioactivity levels in the marine environment, specifically along the EEZ of Qatar have been measured. The EEZ of Qatar encompasses numerous marine resources like fisheries, corals, mangrove swamps, extensive sea grass meadows, shrimp, oyster beds and sponge, all of which needs protection and conservation. During the last 30 years, the Gulf marine environment have been subjected to several threats, especially from the Gulf war events which exerted a great pressure on the marine environment and exposed its resources to damage. Despite the availability of scientific data on the contamination of the environment with metals and hydrocarbons, at present there is very limited information on the exposure of the Gulf environment to radioactive material. This is particularly important, especially with the increase in the number of nuclear power activated vessels visiting the Gulf, the continuous international threat for destroying the Iranian nuclear facilities and the competition between Gulf states to own nuclear facilities in the near future for peaceful use and power generation. Radionuclides have been released to the environment from a multiplicity of sources, both planned and accidental. A very large part of this project has been to collect samples from the marine environment, and measuring and analyzing them for gamma-emitting radionuclides. These samples include water filters, sediments as well as biota samples. As no similar study has been conducted previously in Qatar, the results should provide a useful baseline level for future reference and any further projects. The concentration factors are below the recommended ones by IAEA. At present there is no significant impact on human health from radioactivity point of view through consumption of marine food from the Persian Gulf. The current baseline data generated of 137Cs, 40K and other radioncuclides of interest suggested that, there is no exceptional natural or anthropogenic radionuclide concentrations found in the marine environment of Qatar. This is backed up by the comparison of the results with similar studies from other countries.
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Marine environmental legislation in Qatar: Current mechanism and future challenges
المؤلفون: Omar Mohammed FarajMarine Environmental Legislation in Qatar: Current Mechanism and Future Challenges Max-Planck Foundation, Heidelberg,Germany Omar Mohammed-Faraj, LL.M. Research Fellow The state of Qatar witnessed rapid developments in the last decade, booming economy and solid steps towards the building of a prosper state. These changes in economy and the market demands for Qatari gas and oil put the country's marine environment under serious threats. It is so hard to assess the magnitude of the threats to the marine environment in Qatar and to Qatar's coastal waters; however potential threats can be identified. Over exploitation of fish stocks, (catch of fish in Qatar increased from 4271.3 tons in 1995 to 7139.6 tons in 2000 according to State's report in 2000) for an increase of approximately 67% since 1995. Many marine species like turtles are under serious danger. This constitutes a threat to the marine ecosystem in this country. Critical effects for onshore, offshore discharges including oil spills, ship ballast and pipeline releases damages severely the marine environment. This paper is to examine the marine environment legislation in power at the State of Qatar. Environment Law No.30 of 2002 and Law No.4 of 1983 together with many other decrees, regulations will be examined. The focus will be on pipelines releases and the liability according to the Qatari marine environmental legislation. The existing law did not provide a clearly identifiable responsible party, matters like the compensation for damages to the marine environment must clearly clarified. The paper will include a comparative study of the liability for any pipelines releases in other maritime jurisdictions with an overview to the legal status of marine cables and pipelines in the United Nations Convention on the Law of the Sea 1982 (UNCLOS) which Qatar is a member since December 2002. Qatar needs a unified marine environmental legislation to replace the existing marine environment protection regulations which can be modified or referred to in the new legislation. The methods used to conduct this study are comparative legal analysis, various updated surveys, and existing laws. The aim of this study is to put a focus on the legal mechanism for countering marine pollution in the State of Qatar and identify the needs for improvements in the existing marine environmental legislation. Extending the protection given by law to the marine protected areas (only 0.25% of marine areas in Qatar are protected according to a report by the State of Qatar in 2010) and encouraging legal research in the field of marine pollution is important tool to fill any gaps in the current mechanism. The role of the international conventions ratified by the State of Qatar will be substantial in modulating the current statutory mechanism. The study paper will develop recommendations regarding the identified points of discussion taking into consideration the Qatari context.
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Exploiting the potential of halophytes for third generation biofuel production
المؤلفون: Ajmal KhanExploiting the potential of halophytes for third generation biofuel production M. Ajmal Khan Qatar Shell Professorial Chair for Sustainable Development and Professor, Department of International Affairs, College of Arts and Sciences, Qatar University, PO Box 2713, Doha, Qatar Author for correspondence: [email protected] ABSTRACT Increasing urbanization and industrial developments are accompanying intense utilization of fossil fuel such as petroleum and natural gas. Combustion of these conventional fuels causes environmental pollution especially the emission of green-house gases. Atmospheric concentrations of these green-house gases have increased substantially since the first industrial revolution. These green-house gases cause global warming which in turn is linked to many environmental problems such as sea-level rise and weather anomalies. As a result, researchers are looking for sustainable and environment-friendly energy alternatives. Biofuels - bioethanol and biodiesel from halophytes (naturally salt tolerant plants) may provide such an alternative. The argument used against bio-fuel crops that they are competing with human food resources, is not applicable to halophytes as they utilize saline resources which are considered as waste. Besides, the production of energy from plant biomass would be less detrimental to environment than conventional fossil fuels, as it would emit the same amount of CO2, which would have been fixed during photosynthesis. The potential of halophytes as a source of biofuel is now under investigation. We are reporting here an initial screening of coastal halophytes from Pakistan, which could be useful as bioethanol feedstock.
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Atomistic molecular dynamics simulations for CO2 - H2O - NaCl at conditions relevant to CCS processes
المؤلفون: Othon MoultosEmissions of long-lived greenhouse gases are believed to be a major driver of climate change. Carbon dioxide is the most important greenhouse gas[1] and one of the most prominent strategies to lower its emissions is carbon capture and sequestration (CCS)[2]. CO2 can be stored in geological repositories, in which sodium chloride (NaCl) is the most common dissolved salt. For the optimum design of any CCS process, accurate experimental data and computational models are necessary. This study focuses on generating and validating molecular-based models and methodologies to allow for reliable prediction of the thermodynamic and transport properties of CO2-brine mixtures over a broad range of temperatures and pressures relevant for geological storage. We employ Atomistic Molecular Dynamics (MD) simulations, which is widely used to predict phase equilibria, transport, and other properties of gases, liquids etc. The current study aims at: (a)Determining the accuracy of current molecular models over a broad range of temperatures, pressures and salt concentration relevant to CCS processes with respect to phase behavior and transport properties of CO2 - H2O - NaCl mixture, (b)Developing efficient computational methods and improved potential models for these properties, (c) Assessing the accuracy of SAFT/PC-SAFT based models for the phase behavior of CO2-H2O-NaCl mixture and improving the models using also data generated through molecular simulations and (d)Developing appropriate engineering models for the correlation of viscosity and self-diffusion coefficient experimental and molecular simulation data for the CO2-H2O-NaCl mixture. More specifically, in this work, we study the mutual solubility and interfacial tension in the CO2-H2O-NaCl system over a broad range of temperatures, pressures and NaCl concentrations, using direct interfacial MD simulations. Also we calculate transport properties such as viscosity, self-diffusion coefficient, thermal conductivity. Additionally, we assess the predictive abilities of several combinations of existing H2O, CO2 and NaCl models. To describe water, CO2 and NaCl we use various intermolecular potential models[4,5,6,7,8] that provide property predictions for the CO2-H2O-NaCl mixture over a broad range of temperature, pressure and composition. In addition, the estimated accuracy of the model for each property and for specific conditions will be reported. Our group takes advantage of recent developments of efficiently parallelized codes such as LAMMPS[9] and GROMACS[10]. [1] Metz B, Intergovernmental Panel on Climate Change. Working Group III. Climate Change 2007: Mitigation of Climate Change: Contribution of Working Group III to the Fourth Assessment Report of the IInter-governmental Panel on Climate Change. Cambridge; New York: Cambridge University Press (2007). [2] International Energy Agency, A Policy Strategy for Carbon Capture and Storage (2012). [3] Jorgensen, W.L. J. Am. Chem. Soc., 103(2), 335 - 340 (1981). [4] Berendsen, H.J.C., Grigera, J.R. and Straatsma, T.P., J. Chem. Phys., 91(24), 6269 - 6271 (1987). [5] Harris, J.G. and Yung, K.H. J. Phys. Chem., 99(31), 12021 - 12024 (1995). [6] Potoff, J.J. and Siepmann, J.I. AlChE J., 47(7), 1676 - 1682 (2001). [7] Smith, D.E. and Dang, L.X. J. Chem. Phys., 100(5), 3757 - 3766 (1994). [8] Deublein, S., Reiser, S., Vrabec, J. and Hasse H. to appear (2012). [9] See: http://lammps.sandia.gov/. [10] See: http://www.gromacs.org/.
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Investigation of the mechanical and chemical properties of aluminum waste incorporated concrete
المؤلفون: Nesibe Gozde OzerkanPortland cement-based products (primarily concretes) are the world's most commonly used building materials, and due to its huge production world-wide, especially in developing countries like Qatar, the Portland cement industry is faced economic, energy and environmental problems, such as 7% of total world-wide CO2 emissions. For sustainable development, within the scientific community, major international concern over how to reduce CO2 emissions has given rise to a growing interest in the development of materials and technologies able to reduce the impact of Portland cement. One of the possible alternative ways of sustainable development in construction industry is to replace a large percentage of cement with other materials like industrial wastes, slag and fly ash which reduce the environmental impact of manufacturing an equivalent amount of cement and allow industry wastes to be safely recycled into a permanent structure rather than into a landfill site. It is the objective of this project is to investigate the mechanical and chemical behavior of new concrete type obtained by adding aluminum slag which is an impure aluminum mixture that results from metals melting and mixing with flux. The main advantage of this type of concrete over the conventional ones is the reduction in the quantity of raw materials.
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Molecular level simulations of clathrate hydrates: Recent progress with Monte Carlo studies
المؤلفون: Ioannis TsimpanogiannisHydrates are non-stoichiometric inclusion compounds that mainly consist of water molecules that form three dimensional cavities that are stabilized by entrapped guest molecules. Hydrates have been under investigation for many years due to their wide variety of applications in engineering and scientific problems. In particular, their characteristic to encage selectively large amounts of gas into the crystalline structure has attracted significant attention for possible practical applications including the separation of gas mixtures, desalination, storage and transportation of gases (e.g., methane, hydrogen). Vast amounts of natural gas hydrates that contain significant amount of methane could possibly be used as a future energy source. Assessing thermodynamic properties of hydrate-containing systems, such as the hydrate equilibrium pressure and temperature conditions or the exact amount of gas stored in the hydrate structure has been addressed by either molecular level simulations (e.g., Monte Carlo) or continuum level modeling. In either case the Lorentz-Berthelot (LB) combining rules are by far the most common used for the parameters between different types of atoms. This is a result of their success in describing fluid mixtures of nonpolar molecules. However, the LB combining rules perform inadequately when describing the gas - H2O interactions without using a correction factor. An extensive discussion on the use of combining rules is provided in the studies of Delhommelle and Millie (2001), and Haslam et al. (2008). The effect of combining rules has not been addressed adequately in the hydrate-related literature. The vast majority of studies have considered the LB combining rules. In the current study we report two series of Grand Canonical Monte Carlo (GCMC) simulations: (i) simulations along the three phase (H-Lw-V) equilibrium curve, and (ii) simulations at pressure and temperature conditions that are off-hydrate-equilibrium. For both cases the exact geometry of hydrate crystals is known from diffraction experiments and therefore, the formation of hydrates can be simulated as a process of gas adsorption in a solid porous material. In the first case, we examine the effect of deviations from the LB combining rules on the cavity occupancy of Argon hydrates. The specific system is selected as a result of the characteristic behavior of Argon to form hydrates of different structures depending on the prevailing pressure. In particular, sII hydrate is formed at lower pressures, while sI hydrate is formed at intermediate pressures, and finally sH hydrate is formed at higher pressures. In the second case, an extensive series of GCMC simulations for the case of all the known hydrate structures, sI, sII, and sH that hydrogen is known to form, is performed. During the simulations a number of water force-fields are examined regarding their effect on the storage capacity of hydrates. In particular, the following popular water force-fields are considered: SPC/E, TIP4P, TIP4P/Ice, and TIP5P. The Langmuir constants for each type of cavity and hydrate structure are reported as a function of temperature and pressure. Therefore, the storage-capacity of the different hydrate structures can be calculated. Acknowledgment Financial support by Qatar National Research Fund (project NPRP 6-1547-2-632) is gratefully acknowledged.
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Conversion of carbon dioxide to useful fuels using photoelectrochemical technology
المؤلفون: Dong Suk HanProduction and use of hydrocarbon energy result in enormous release of carbon dioxide (CO2) into the atmosphere, eventually causing the global climate change. Furthermore, the world is now facing a dual energy challenge, which is to minimize use of fossil fuels to decrease the impact of CO2 on climate change while meeting the growing global energy demand. To solve these challenges, development of an innovative technology capable of reducing or reusing CO2 as well as producing environmental-benign and sustainable energy using renewable energy sources is urgently required. As such, a technology that can produce solar fuel energy using water oxidation and CO2 reduction that mimics natural photosynthesis has been attracting extensive interest (Figure 1). Many approaches for solar-driven fuel production using artificial photosynthesis have been suggested and developed. Among them, a promising one is to use semiconductor-based photoelectrochemistry (PEC) because there are much potential to meet the requirement for sustainable, selective, and efficient production of solar-driven fuels and the proton-coupled electron transfer to CO2 by enhancing light absorption, charge generation, and separation through construction of a junction between semiconductors. For CO2 reduction, bare and Cu-electrodeposited p-Si electrodes were immersed in 0.1 M borate (pH 9.2) or 0.1 M bicarbonate (pH 7.2) electrolytes, to which AM 1.5 light of 100 mW/cm2 (1 Sun) was irradiated. Chopped linear sweep voltammograms showed that the onset potential is anodically shifted by 0.5 V and the photocurrent is significantly enhanced by Cu deposition. To examine the competitive reaction between water reduction (hydrogen evolution) and CO2 reduction occurring on p-Si/Cu, three different gases (O2, N2, CO2) were purged into the bicarbonate electrolyte solution. The purged gases change little the onset potentials. A high photocurrent with N2 compared to O2 indicates that water reduction becomes a primary electron-quenching process in the absence of dissolved oxygen. At low potential range, CO2 is most effective whereas N2 becomes more effective with increasing the negative potentials. Because the two-electron reduction potentials of H2O (H2 evolution) and CO2 (CO evolution) are very similar (only ~100 mV difference), the high photocurrent with CO2 at low potential range implies that the CO evolution may be the primary process. Instead of p-Si, a novel photocathode, p-CuFeO2 was also synthesized and its PEC performance was tested. The onset potential was around -0.2 V vs. SCE and the photocurrent increased with increasing the film thickness. Due to its transparency, this photocathode can be coupled with other transparent photoanodes for CO2 conversion.
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Remote gas detection system for identifying fugitive emissions
المؤلفون: Hazem Abdel-MoatiIdentifying fugitive emissions from large scale LNG and gas processing and handling facilities is a difficult time and resource intensive process. Because of the limitations of hand held gas detection devices, and the sheer size and complexity of these facilities, smaller leaks may go undetected for extended periods of time and unintended releases may occur when plant personnel are not present or the area monitored. While fugitive emissions are typically not of immediate safety and human health concern taken individually, reducing the total emissions from a large plant or a regional industry footprint could very well have an appreciable positive impact on the environment. ExxonMobil Research Qatar (EMRQ) has developed a Remote Gas Detection (RGD) system that integrates computer vision algorithms and infrared (IR) optical technology that can autonomously scan for and identify small leaks such as those associated with fugitive emissions. Efficient identification of these emission sources will lead to better control and maintenance activities. The RGD system utilizes a custom build component based IR camera and integrated cooler assembly, and a computer vision algorithm that analyses the video output from the IR imagers to determine the presence of hydrocarbon plumes. Most hydrocarbon plumes have strong absorption peaks in the narrow mid-wave IR region. The algorithm takes advantage of the difference in contrast between a hydrocarbon plume and the background in each pixel of an IR image and the temporal changes due to plume behavior for the analysis. The algorithm compares sequentially collected IR images and uses a multi-stage confirmation process to confirm the detection and has built-in multiple filters that mitigate interferences like steam, and other moving objects such as humans and trees. Early field tests indicate that a 4 lb/hr propane leak could be autonomously detected from a distance of up to 800 feet. Also, initial testing comparing the RGD system to point and path detectors showed that a 2 lb/hr propane leak was successfully detected from 60 feet using the RGD system but did not elicit any response from a point detector located downwind 18 feet away. Multiple deployment opportunities at process facilities are currently underway. Results from field testing at these process facilities will help researchers investigate the effect of temperate and harsh weather conditions, the effect of varying temperatures and gain a better understanding of equipment wear and tear, maintenance requirements and possible life expectancies. These data sets will produce an accurate assessment of the performance of the RGD system under actual working conditions and will be used to qualify the technology for widespread adoption within the industry.
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Techniques for isolation and purification of marine microalgae from the coast of Qatar
المؤلفون: Sarah BachaBackground Unicellular algae, at the base of aquatic food chains, are particularly sensitive to a wide range of pollutants and are therefore important in toxicity tests for hazard assessment and aquatic environment protection. EMRQ (ExxonMobil Research Qatar) in collaboration with ESC (Environmental Studies Center, Qatar) and the Ministry of Environment, Qatar, is investigating the impact of common toxicants on the performance (growth and survival) of microalgae found in the coastal regions of Qatar. The present work was undertaken to establish the techniques for the isolation and purification of four microalgal species in order to culture them under specific laboratory conditions. Objectives * To conduct laboratory experiments to determine the most appropriate method for the isolation and purification of different microalgal species found in the coastal waters of Qatar. * To establish axenic cultures of the purified unialgae at EMRQ. * To conduct chronic toxicity tests of certain toxicants commonly found in seawaters on the microalgal species isolated and cultured. Methodology Different phytoplankton species were identified and isolated from freshly collected seawater from various sites around the coast of Qatar. * Unialgal isolates were obtained by four major techniques: streaking, spraying, serial dilution, and single-cell isolations by capillary method * Purifications of the unialgal samples to obtain axenic cultures were realized by micropipette washing technique followed by streak-plating technique and using antibiotics. Results The isolation by streak-plating showed to be the most suitable method for the small non motile microalgal species (<10mm) that grow well on a substrate. The serial-dilution technique looked to be ideal for all types of microalgae, specially the small motile species. The isolation by picking-up a single cell was found to be more adequate for the large phytoplankton species. A mixture of antibiotics showed to be more effective than the use of any individual antibiotic. Conclusion and Discussion A few microalgae have been successfully isolated and purified using the techniques mentioned above. The streak-plating method seems to be the most promising technique for the species found in Qatari waters. At present we are doing experiments to determine the specific biological and physical conditions for culturing the purified microalgae species for optimum growth at EMRQ. The purpose of obtaining axenic cultures of phytoplankton is to study the impact of specific toxicants on these species by performing chronic toxicity tests.
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Effective management of future smart grids
المؤلفون: Linda StegWorldwide, the current energy system increasingly shows economic, social and environmental drawbacks and it does not appear to be sustainable. Among the most pressing problems are climate change due to CO2 emissions, the depletion of fossil resources, the security of energy supply, and threats to economic development. These problems can be addressed by moving towards energy systems that increasingly rely on renewable and sustainable energy sources. At the same time, the rapid progress in renewable energy harvesting and information and telecommunication technologies offer unprecedented opportunities for energy generation, distribution and management, and to more strongly involve people in the process of energy generation and management, which is needed to further enhance the sustainable energy systems. Indeed, renewable and sustainable energy sources are likely to be produced and distributed in a decentralised manner, and require energy management systems that differ greatly from the current centralised system. Hence, the integration of renewable sources has major implications for the design and management of energy systems, relying on innovative ICT solutions and stronger user involvement that facilitate supply and demand matching. Effective energy management requires the active participation and support of end users, who should accept the energy management systems, and adapt their energy use to the available demand as to enhance the efficiency and stability of the energy system. Hence, the design of future smart grids should be based on sound behavioural models, which should be integrated in ICT centred solutions that facilitate supply and demand matching. More specifically, we need to understand how truly complex information on energy production, use and storage can be effectively communicated among relevant actors, and what type of information and incentives should be provided to realise effective supply and demand matching. In addition, we need to understand how to take into account cultural specifics in the design of energy management systems, to enhance effective energy management across the world. The active and aware involvement of the end-user can only be achieved if a scalable and reliable ICT infrastructure is in place, which naturally interfaces the energy flows with the decision autonomy of the people. Hence, the design of effective energy management systems should be take into account key behavioural as well as ICT requirements in an integrated way. Our proposal is thus to investigate (1) ICT based solutions for monitoring and controlling the power grid focusing on the distribution networks (medium-low voltage) and buildings (offices and residential complexes) specific to the Qatar context; (2) behavioural models on effective and acceptable incentives to match energy supply and demand; (3) cultural specificities in the design of energy management systems by comparing results from research in Qatar to similar research in other parts of the world, in particular Europe. Together, these will provide important insights in how to promote efficient and stable renewable energy systems that meet Qatar's sustainability goals.
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Modeling of thermodynamic derivative and transport properties of CO2 mixtures for pipeline transportation
المؤلفون: Nikolaos DiamantonisIntroduction Carbon Capture and Sequestration (CCS) is one of the most promising technologies for the reduction of CO2 accumulation in the atmosphere. Continuous research on the topic develops methods for utilising the captured CO2 for enhanced oil and gas recovery (EOR and EGR). Through the research in this field, challenges that regard the mitigation of environmental pollutants such as CO2, as well as the increase of efficiency of oil and gas production processes can be addressed. Quite an important role in the design of these processes, and especially for the transport of CO2 streams via pipelines, is held by the thermodynamic modeling of pure CO2 and CO2 mixtures. The stream in the pipeline contains mainly CO2, together with many other gases, depending on the source of the stream, and the capture technology that precedes the transport. Typical impurities include CH4, N2, O2, SO2, Ar, and H2S, all of which can have a substantial impact on the thermodynamic behavior of the stream, both in the pipeline and out of it, in the unwanted event of a fracture. Methodology In this work, cubic and SAFT-based equations of state are used in combination with specific models for the calculation of phase equilibria, derivative thermodynamic properties and transport properties of CO2 mixtures. Their performance is evaluated against available experimental data from the literature. Especially for transport properties, established viscosity models from the literature based on friction theory, are combined with the above mentioned equations, in order to assess their ability of predicting viscosity of CO2 mixtures of interest to the CCS and EOR processes. Diffusivity and thermal conductivity are also investigated with the use of models combined with a range of equations of state, towards a unified approach of the thermodynamic properties prediction for CO2 containing systems. Conclusion In most cases, the higher order EoS are more accurate than the cubic EoS in the case of predictive calculations (no binary parameters used) of phase equilibria. Nevertheless, the two classes of EoS provide similarly good results when using a temperature independent binary interaction parameter. Derivative properties are more accurately captured by the SAFT family EoS, due to the higher physical content that they have over the cubic EoS. The pure components viscosity calculations with the different types of EoS compared in this study do not exhibit great deviations, owing that to the fitting procedure that was necessary for each EoS. On a related note, the need for more experimental data of derivative and transport properties of CO2 mixtures at conditions that cover the design and operation of CO2 pipelines becomes obvious. Acknowledgment The authors acknowledge financial support from the 7th European Commission Framework Program for Research and Technological Development for the projects "Quantitative failure consequence hazard assessment for next generation CO2 pipelines" (CO2PipeHaz, Project No.: 241346) and "Techno-economic Assessment of CO2 Quality Effect on Capture, Transport and Storage" (CO2Quest, Project No.: 309102).
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Integrated environmental research to support Qatar industrial development
المؤلفون: Eric FebboIncreasing development along the coastline and offshore Qatar results in continuous interaction between industrial activities and the biodiverse Qatar Marine Zone. Enhancing the understanding of this environment and the potential for impacts is essential to Qatar. The ExxonMobil Research Qatar (EMRQ) Environmental Management Research Program is working with local and international partners to develop the scientific knowledge needed to better understand environmental risks specific to this region, and is developing technologies to enhance environmental management capabilities. Scientists at EMRQ are using state-of-the-art research labs combined with field studies and eco-risk model development to understand, assess, predict and mitigate potential impacts to the local marine environment that may occur as a result of Qatar's industrial activities. In addition, we are developing state of the art technologies and data acquisition / management systems that will allow for effective identification of baseline environmental resources, monitoring ecosystems to identify change, and analyzing environmental data to support rapid and successful decision making. Taken together, the projects undertaken in this integrated program are supporting Qatar's ability to understand and manage its resources responsibly. Several projects are described in detail within the framework of how the information and tools developed are integrated into the environmental management process. Sensitive ecosystem monitoring, laboratory based ecosystem risk assessment tool development, hydrodynamic modeling, ecological baseline surveys, remote sensing and mapping are the main projects to be discussed. Monitoring Qatari corals and seagrass over the last few years with the use of new technology as well as in-situ temperature monitoring devices has provided insight into the factors affecting these sensitive ecosystems. The development of laboratory based environmental risk studies provides methods to utilize indigenous species to determine the potential effects of chemicals and other parameters in the environment. Three dimensional modeling of hydrodynamic processes in the Qatar marine zone allows visualization of fate and transport of pollutants and can be used to assess and predict impacts. Baseline surveys provide a great deal of data cataloguing biodiversity, and documenting physical and chemical processes in land, sea and the interface in-between. New cutting edge techniques like remote sensing from space born satellites or small autonomous vehicles deployed in the sea allow large or targeted areas to be studied and classified in a more rapid manner than traditional field studies. This data, if properly formatted and managed, allows for accurate mapping and temporal analysis by acquiring imagery at timed intervals. The system used to integrate environmental data and modeling analysis tools is a geographical information system (GIS). In today's world, a single development project can result in tens or hundreds of thousands of electronic files and terabytes of data characterizing the environment. A structured file geo-database and GIS system provides a mechanism to manage and analyze enormous amounts of information and to provide reports and visual tools for managers within government and industry to make informed decisions for environmental management or risk assessment purposes.
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Optimization Of Splits Spectrum And Multi-Junction Photovoltaic Cells Using Cuckoo Search Inspired Hybridization Of The Nelder- Mead Simplex Algorithm
المؤلفون: Raka JovanovicIn the recent years the performance of photo-voltaic (PV) cells has been significantly improved by using multi-cell devices. In such systems, few layers of different cells are combined to maximize the efficiency by exploiting the use of different wave lengths of light. Using this approach efficiency of over 40% has been achieved. The two most promising methods are splits spectrum and multi-junction photo-voltaic cells. With the development of new technologies it has become possible to create more complex PV sells consisting of a higher number of layers. For future development of such PV cells it is of significant importance to have bounds for the optimal possible efficiency. While it is relatively simple to find them in case of two or three layers it becomes significantly more complex in case of a higher number of layers. This is due to the fact that it is necessary to find the of a multi-parameter function, which is computationally expensive. The problem becomes even more complex because it is hard to find the corresponding gradient that could simplify the calculation. There is a wide range of non-gradient based methods like simulated annealing, genetic algorithms, particle swarm optimization, Nelder-Mead Simplex method[1] that are generally used solve this type of problems. The performance of such methods is highly dependent on the function that we wish to minimize. In the case of the problem of interest, initial test have shown that Nelder-Mead Simplex algorithm manages to out preform mentioned more complex population based methods. One of the reasons for this is the fact that due to physical properties of the problem we have a good initial guess of the solution. Our research has focused on improving the performance of this algorithm by incorporating some type of swarm intelligence. Previously, similar hybridization of Nelder-Mead simplex algorithm using genetic algorithms[2], ant colony optimization[3] and particle swarm optimization[4] have proven to be very efficient. In the recent years the Cuckoo Search[5] algorithm has been gaining on popularity as an optimization method due to its good performance, robustness and simplicity of implementation. One of the main problems of hybridized methods is that although they achieve better results they often become very complex for implementation. In our work we introduce a cuckoo search inspired hybridization of the Nelder-Mead simplex algorithm that manages to avoid this drawback but still achieves significantly better results than the original method. In our tests we show that the proposed method also achieves good results on standard benchmark functions. The cuckoo search is often a competing method to the particle swarm optimization; because of this we also give a comparison to previously published results of hybridization of Nelder-Mead simplex using this method.
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Channel Coordination In Supply Chains Under Carbon Emission Considerations
المؤلفون: Adel ElomriAn increasing number of firms are integrating carbon emission concerns into their operational decision-making. Some of these actions are motivated by individual initiatives towards corporate environmentalism. While some other are driven by environmental regulation pressures. Policies such as carbon caps under the Kyoto Protocol and carbon tax have been introduced in many countries as mechanisms to induce firms to adopt the low carbon society. In this setting, we present a model for analyzing the impact of carbon emission considerations on the coordination between two/or more different business entities. In the absence of carbon emission considerations, channel coordination has been widely studied in the supply chain management literature. It has been shown that both entities are often better off under the coordinated channel. Several mechanisms and contracts have been then studied to settle down such coordination under different scenarios. The purpose of this research is to investigate these traditional (cost driven) results under carbon emissions considerations. In other terms our objective is to illustrate how the incentives for the coordination are affected by the presence of carbon emission firms' concerns. In our initial analysis we consider traditional buyer-vendor coordination by associating carbon emission parameters with ordering and holding decision variables. We examine how the values of these parameters as well as the considered regulatory emission control policies affect cost and emissions. The corresponding carbon emissions are incorporated into the model through the consideration of various regulatory policies that include : (1) strict emission caps: both of the supplier and the buyer are subject to mandatory caps on the amount of carbon they emit, (2) carbon tax policy: the supplier and the buyer are taxed on the amount of emissions they emit and (3) cap and trade system: the supplier and the buyer are subject to carbon caps but are rewarded /penalized for emitting less/more than their caps. Under carbon emission considerations, the centralized solution remains profit-optimal but not necessarily emission-optimal. This means that the joint profit is often increased when the channel is coordinated. However, the amount of total carbon emissions may be higher than what could be emitted by the retailer and the supplier when they work individually. We identify conditions on cost and emission parameters under which the joint policy is both profit and emission optimal. We also show that the outcome of the coordination is very sensitive to the type of the regulatory policy, for instance some policies are providing greater incentives than others for coordination.
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Developments in green sustainable data center infrastructure management (DCIM) energy tools
المؤلفون: Damian DaltonEnergy management and reduction is one of the major challenges in the Cloud industry's data centres. The Uptime Institute's 2012 report, the industry's leading authority, highlighted the crisis in data centre energy management. 30% of data centres will run out of power, space and cooling in 2012. On average there's a 90% energy overhead in data centre operations, yet 55% of servers use less than 10% of their capacity. The 500,000 data centres worldwide have a server electricity consumption of 400 Billion kWh/year (approx $40 Billion ) which is growing at 12% CAGR, yet only 11% of the centres monitor their consumption. The global CO2 emissions of these centres, is equivalent to the airline industry, 2% of global emissions. It is expected that by 2020 20% of Europe's electrical energy will be data centre related. Data centre cooling requirements also have an enormous hydro footprint. A 1 MW data centre in a U.S-type climate has an annual hydro footprint of 99 million litres/annum Yet studies have shown that operational energy savings of 40% and substantial reductions in physical space, cooling requirements and water consumption can be achieved, where comprehensive and effective energy monitoring and management systems are employed. These can deliver a ROI within months, and further savings which extend over the centre's lifetime. The technologies which have the potential to deliver these benefits, DCIM (Data Centre Infrastructure Management) systems have only emerged in the last 3 to 4 years and are still in their infancy. Not surprisingly, a new global industry providing innovative, green, sustainable data centre technologies will be worth €45 Billion by 2016. The main barriers to effective monitoring/management is instrumentation and training. Vast volumes of data are gathered and must be competently analysed. Most monitoring systems, involve some form of physical metering and cabling and downtime, a major challenge when 10's thousands of servers are involved. Furthermore, all approaches physical and hybrid approaches limit the level of monitoring visibility to the server, individual processes cannot be monitored. A spin-out company from University College Dublin Ireland, Stratergia, has developed a unique data centre energy management system PAPILLON. It is totally software-based, measuring every server's energy consumption in real-time. It is intuitive to use, operates on any platform and can be installed in hours without any downtime or retrofitting. It uses a client-server type architecture. Software agents on servers communicate periodically, to a master server which has power models for each server type. Using the power models, the master computes in real-time and saves in a data base, all relevant energy information of the centre. In operation, Papillon identifies and quantifies energy saving actions that can be implemented, and coupled with electricity network data, more sustainable energy sources can be introduced into the power input of the centre. Papillon has been trialled at Swedish Compare Testlab and is one of the core tools being installed at state-of-the-art data centres at Kajaani, Finland and Cenit, Spain for a new international EU-funded Masters programme in green, sustainable data centre management.
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Microencapsulation for self healing of concrete
المؤلفون: Marwa HassanConsiderable interest has been directed in recent years toward the use of self-healing materials in concrete. The concept of microcapsule healing is based on a healing agent being encapsulated and embedded in the concrete. The objective of this study was to evaluate the effects of preparation parameters, namely, temperature, agitation rate, and pH on the shell thickness and size (diameter) of the microcapsules; as well as to evaluate the self-healing mechanism in concrete through experimental testing performed in laboratory. Two healing agents were evaluated in this study, i.e., dicyclopentadiene (DCPD) and sodium silicate. The experimental test matrix used in this study is shown in table 1. The anatomy of the microcapsules is shown in figure 1. Based on the results of the experimental program, it was determined that, as the pH was increased, the shell thickness increased for sodium silicate, while the shell thickness reached a minimum at a pH value of 3.4 for DCPD. Sodium silicate shell thickness was almost twice the shell thickness for DCPD. The most uniform and coherent microcapsules were produced at a temperature of 55°C. For the DCPD microcapsules and up to 49°C, the solution remained an emulsion and no encapsulation took place. The increase in agitation rate resulted in a decrease in the average diameter of the microcapsules for DCPD as shown in figure 2. On the other hand, the diameter of the microcapsules remained constant for sodium silicate microencapsulation as the agitation rate was increased. Testing of concrete specimens modified with the two healing agents (DCPD and sodium silicate microcapsules) was conducted. For sodium silicate, improvement in the modulus of elasticity of the concrete before and after healing was observed at a pH value of 3.1 and sodium silicate content of 5.0%. At other pH values, the effect of the sodium silicate microcapsules on the concrete performance was negligible. For DCPD and sodium silicate microcapsules, the healing agent was effective in increasing the modulus of elasticity of concrete after cracking as shown in figure 3.
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A new normalized digital feedback control for grid connected distributed generation system
المؤلفون: Mohamed Abdallah TRABELSIBackground & Objectives Distributed Generation systems such as fuel cells, solar, and wind play a crucial role in producing energy with low or zero CO2 emissions and are explored for various stand-alone and grid connected applications. Inverters (conditioners) play an important role in interfacing the DG sources to the grid as they link them with controlling the power flow. Therefore, control techniques for inverters should achieve high performance not only during normal operating conditions of the grid, but also under fault conditions. This work proposes a newly designed Real Time Digital Feedback Controller for a grid connected PV system. A multilevel Flying Capacitors Inverter along with inductor and step-up transformer is used as an interface between the PV system and grid. The proposed controller is Deadbeat type controlling simultaneously the grid current and capacitor voltages variables using a weighting factor to ensure a proper balancing among the controlled variables. Furthermore, the proposed approach is offering the possibility of duty cycles normalization when the reference is not achievable within the sampling period. The newly designed controller transfers the power to the grid even under voltage fluctuations resulting from grid faults. This Voltage Ride Through capability is made possible without any noticeable current overshoot, while maintaining unity power factor and low harmonic distortion. Methods: In this work, a new normalized Deadbeat control technique with VRT capability is proposed to transfer power to the grid with unity power factor. Unlike other control techniques, the proposed control is based on a hybrid model taking into consideration duty cycles, state variables, and external disturbances (voltage sags). Furthermore, a normalization of the control vector is presented when the calculated duty cycles do not satisfy the physical condition. The validated approach consists of a serial of mathematical calculations (min, max) in order to ensure the generation of duty cycles within the physical domain. Results & Conclusion: An experimental power conditioning unit was developed to transfer the power from a DG system to the grid. Simulation and experimental results obtained on 1kW prototype validate the high performance of the proposed control under grid voltage sag. Smooth transition between normal and faulty operation is achieved. Keywords: Normalized Deadbeat Controller, Voltage Ride Through Capability, Grid connection, Unity power factor, Solar Energy Interfacing.
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Status of worldwide renewable energy installation and guidelines for the connection of PV systems to the power grid
المؤلفون: Haitham Abu-RubThe increasing price of conventional fossil fuel and the need to reduce green-house gas emissions have prompted the adoption of clean electrical energy generation sources. The abundance of renewable energy, particularly solar and wind, over the world combined with increasing efficiency of the Photovoltaic (PV) cells has led to reducing cost per kWh of generated green electricity and created potential for establishing high power renewable energy systems at medium voltage scale. The design, fabrication, installation and testing of a large PV power generation systems still, however, pose great challenge in term of obtaining highly-efficient, highly-reliable, transformer-less with buck/boost voltage capabilities, and reduced cost and maintenance. This work is aimed to present the status of renewable energy installation worldwide and to discuss grid connected issues. The increasing penetration of PV energy has motivated the establishment of grid connection requirements. The requirements for power injection should be clearly defined: The grid requires sinusoidal AC with stable voltage and frequency, and the harmonics content should be kept within limits as addressed in various standards, codes, and guidelines. Hence, PV plants connected to the public grid give rise to two highly important requirements: the power quality of the grid should not be reduced when solar power is fed into the grid; and personal safety must be ensured in the event of mains interference. Large PV systems are usually tied at high-voltage level. Such systems consist of generation, transmission, distribution phases, and consumers at the end [1]. This proposed work will discuss the status of renewable energy worldwide installation at high level and will [resent the standards and regulations for the connection of PV renewable energy sources to electric grid. Different technical and non-technical issues related to the installation and the operation of such systems will be carefully discussed, analyzed and related problems investigated. There is a pressing need to review and to evaluate the design and operational constraints of large-scale renewable energy systems, therefore this work aims to discuss and open-up new avenues in this direction. References [1] H. Abu-Rub, M. Malinowski, K. Al-Haddad, Power Electronics for Renewable Energy Systems, Transportation and Industrial Applications. Hoboken, NJ: John Wiley & Sons, 2014 (in press).
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