Current and future pollutant enussion legislation calls for decreased NOx emissions from combustion systems. A review of techniques used for NOx abatement led to the choice of combustor redesign to be the most cost effective method available. This led to the design, construction and development of a combustion system that utilised a Coanda ejector to generate recirculation of the exiting high temperature combustion products to mix with the air supply. Cooling of the burner was integrated into the design through the use of the air and fuel supplies. Computational fluid dynamics was used to model and aid development of the design. The model was used to predict NOx and CO emissions and the fuel-air mixing pattern. This, along with an analysis of experimental results and observations led to an understanding of the burner operation with respect to pollutant emissions and stability. NOx emissions from the Coanda burner were found to be lowest when using a 0.2 mm Coanda gap width, resulting in 16 ppm NOx being emitted at an air to fuel ratio of 1.5. However, the use ofa 0.2 mm Coanda gap width required an air supply pressure of up to 4 bar. The use of a 0.5 mm Coanda gap width enabled burner operation at lower air supply pressures. The resulting NOx emissions were measured as 23 ppm at an air to fuel ratio of 1.I, with a corresponding exit gas temperature of 2200 K. Flue gas recirculation quantity, flame stability, flame stabiliser shape and operational limits proved to be inter-linked in the reduction of NOx emissions. It was found that fuel-air mixing was controlled by the entrainment properties of the Coanda ejector and the flame stabiliser. The average oxygen concentration entering the combustion chamber when using a 0.2 mm and 0.5 mm Coanda gap width was 13.7 % and 16.6 %, respectively. Due to the position of the fuel injector, a fuel rich region formed behind the flame stabiliser. With a suitable flame stabiliser geometry and the use of 'fingers', low NOx combustion and flame stability was achieved near stoichiometric conditions. It was shown that the design of the burner enabled very low pollutant emissions near stoichiometric conditions, resulting in high exit gas temperatures. Conceivable applications of this type of burner could lie in small and intermediate furnaces where low NOx emissions are required. Additionally, very high temperature applications, such as glass furnaces could benefit in both cost and pollutant emissions from such a burner.

Thesis advisor: Richard Sweeney / With climate change becoming a global problem more people are paying attention to, a common goal to reduce Greenhouse Gas (GHG) emissions is recognized by most countries. However, usually emission reduction is more difficult to achieve in developing countries because of the lack of advanced emission reduction technology. Thus,one of the important ways to improve emission reduction technology in developing countries is through technology transfer, which is to import more advanced emission reduction technology from developed countries to developing countries. In this study, I explore the level and determinants of technology transfer using data of projects from four sectors under the CDM(Clean Development Mechanism) in China. I find that large scale projects with higher emission reduction amount tend to have higher probability of technology transfer. Also, more economically and technologically advanced provinces tend to have more projects with technology transfer. / Thesis (BA) — Boston College, 2017. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Departmental Honors. / Discipline: Economics.

The aim of this work is to produce a manufacturing strategy for high current (>10 mA) field emission (FE) devices for military (microwave generation) and civilian (particle accelerator electron beam) applications using carbon nanotubes (CNT) as base material. With a particular focus on the relationship of the laser time pulse duration used for cutting CNTs and how this affects the field emission performance. Material selection for this work was narrowed to CNT as they possess unique characteristics such as: high aspect ratio; high thermal conductivity; high chemical stability and high current carrying capacities up to a theoretical limit of 1,200 MA∙cm-1 making them an ideal material for FE. The CNT material studied in this work is produced in two distinct forms, fibres (∅~7-10 μm) and films (h~30 μm), using a floating catalyst chemical vapour deposition process which produces high quantities of CNT material with mixed mechanical and electrical properties. The material is difficult to handle because of its dimensions and is susceptible to environmental changes i.e. electrostatic forces. In order to reduce the variability in electrical properties, a laser purification process was developed. The process consists of locally irradiating an infra-red (IR) laser several microseconds directly at the material. A percentage is vaporised (mainly non-conductive or defective material) and the remaining CNT material shows very high crystallinity with an increase of up to ten times (G/D ratio > 100) compared to the original material and electron mean free path is increased by an order of magnitude. The production strategy is based on directly coating the CNT material with copper using an electroplating process. This allowed for CNT fibre and film to be easily handled and improved the overall electrical contact. Emitter geometry was customised by a laser cutting process to achieve increased enhancement factor geometries, in this case, triangles with 29 tips whilst reducing FE variability. FE performance was quantified by testing the devices in a continuous DC mode with a sweep up to 1,000 V until the material suffered catastrophic failure. The gap distance between the tip of the triangles and the anode was varied to increase the electric field until failure. FE results using the production strategy improved more than 400% compared to untreated material. Applications for these devices are intended to be in the creation of high energy electron beam lines and generation of high powered directed microwaves.

<p>In Rio De Janeiro, 1992, was the first document signed that meant a responsibility for industrial countries to decrease their emissions, United Nations Framework Convention on Climate Change (UNFCCC). Thirteen years later was the first legal binding document signed, the Kyoto protocol, and for the first time industrial countries all over the world was bound to decrease their emissions on greenhouse gases. Within the framework of this commitment, three flexible mechanisms (Clean Development mechanism, Joint Implementation and Emission trading) were introduced with the function to reduce the economical costs of the commitment. The flexible mechanisms Emission Trading (ET) is what this report is about.</p><p>The report starts with a description of carbon dioxide and it’s effect on the environment, thereafter comes a background review of the national agreements who lies as a ground to the implementation of emission trading as a management control measure in Sweden and the rest of the world.</p><p><em><p>Keywords</p>: United Framework Convention on Climate Change, Kyoto protocol, Flexible mechanisms, Emission trading, carbon dioxide </em></p>

Thesis (M.S.)--Oregon Graduate Center, 1977.

In Rio De Janeiro, 1992, was the first document signed that meant a responsibility for industrial countries to decrease their emissions, United Nations Framework Convention on Climate Change (UNFCCC). Thirteen years later was the first legal binding document signed, the Kyoto protocol, and for the first time industrial countries all over the world was bound to decrease their emissions on greenhouse gases. Within the framework of this commitment, three flexible mechanisms (Clean Development mechanism, Joint Implementation and Emission trading) were introduced with the function to reduce the economical costs of the commitment. The flexible mechanisms Emission Trading (ET) is what this report is about. The report starts with a description of carbon dioxide and it’s effect on the environment, thereafter comes a background review of the national agreements who lies as a ground to the implementation of emission trading as a management control measure in Sweden and the rest of the world. Keywords : United Framework Convention on Climate Change, Kyoto protocol, Flexible mechanisms, Emission trading, carbon dioxide

Realize the situation about CO2 emission in Europe and China. Find out which reasons caused the CO2 emission will be changed. We did the data collection: CO2 emissions from China and EU. Energy consumption (include the total, electricity and transportation) and energy structure. Increased CO2 emission caused by Global warming. The CO2 emission increased with fossil-fuel use increased. China almost used of fossil energy, in 2004, domestic use for coal achieve to 67.7% of the total energy consumption. In 2010, the coal supply account for 48% of the world; the coal supply in 2000 to 2009 increased 85.5%. The CO2 emissions in 2009 is 6803.92 mil-tones, increased 13.32% than 2008, No. 1 of world. EU energy structure is keep changed, the rate of utilization for traditional fossil-fuel was gradually reduced. In 2010, the EU coal supply 8% of the world, 2000-2009 presents negative growth (3.8%). The CO2 emissions in 2009 were 4310.3 mil-tones, more than 2008 years to reduce 6.9%. CO2 emission based on energy consumption; Energy consumption is supply a variety of services to people. We must consider with population. China’s CO2/per capita less than average level in world, and lower than most EU countries.   China and EU are planning for future energy structure (reduce the use of fossil-fuel and increase renewable energy construction), that means up to energy saving and emission reduction purpose. The emission reduction of focus is to change the energy structure, reduce fossil-fuel use. China predicting the coal utilization rate under 60% of the total energy consumption. Thus, by 2020, forecast reducing 40-45% CO2 emission based on 1995. EU energy structure better than china, while they planning energy saving reach 20% at 2020, and improve the renewable energy use. By 2020, EU-27 forecast reducing 20% CO2 emission based on 1990 CO2 emission.

In this research, we used the zinc oxide (ZnO) which is die pressed and sintered for studying. We want to know the variations of microstructure and luminescence property when we doped 0.2 mol.% Al2O3 or Li2O to ZnO, or sintered under different atmospheres (high purity oxygen, high purity nitrogen, high purity argon). Using X-ray diffractometry (XRD), scanning electron microscope (SEM), and catholuminescence (CL) spectrometry equipped with a SEM to analyze the different samples. The all six samples¡¦ crystal structure didn¡¦t change via XRD. We investigated for the in-gap-level modification using the CL spectrometry. CL analysis results indicated that ZnO emitted UV light, visible light (blue, green, yellow light), and Near-infrared light emissions. The UV light emission was attributed to the two electronic transitions from the donor level of free exciton and Zn interstitial to valence band. The blue light (2.53 eV) emission was attributed to the donor level of oxygen vacancy-related defect. The green light emission was attributed to the electronic transition from the acceptor level of zinc vacancy-related defect.And the yellow light emission was attributed to the O interstitial and Li-related defects. The Near-infrared light may be attributed to the deep levels recombination.

In this dissertation, proton, two proton, and emission from the 14O + a interactions were studied with the modified thick target inverse kinematics approach. The radioactive beam was obtained by using resonances in the 14N(p, n)14O reaction. The 14O was > 99% pure. By using a beam analysis system, the contaminant-tobeam ratio was suppressed further to the 10−4 level. This makes the 14O beam at TAMU one of the best available. For the 14O(a, 2p) interaction, it was found that the resonance excited states in 18Ne are populated, and most of them decay sequentially to the ground state of 16O, i.e. 18Ne* ! 17F* + p ! 16O + p + p. Two proton events corresponding to the excited state of 18Ne*(8.45MeV), were found to have strong 2p correlation, which is the fingerprint of 2He-decay. Several models were used to explain this decay process, and evidence suggests that this state decays by 2He-emission. By measuring the Time-Of-Flight for protons through the thick target, the location of 14O(, p) reactions occurring at different places in the helium gas target were identified. With this information, we were able to measure a spectrum of protons corresponding to the population of 17F particle stable states in the 14O(a, p)17F reaction. This method provides a new way to measure astrophysically important reactions which involve radioactive nuclei and a particles. By analyzing elastic scattering of 14O and 14C on 4He, a-cluster states in 18Ne* and 18O* were found. Some a-cluster states in 18Ne* were found for the first time.

New regulations like the Clean Air Interstate Rule (CAIR) will pose greater challenges for Coal fired power plants with regards to pollution reduction. These new regulations plan to impose stricter limits on NOX reduction. The current regulations by themselves already require cleanup technology; newer regulations will require development of new and economical technologies. Using a blend of traditional fuels & biomass is a promising technology to reduce NOX emissions. Experiments conducted previously at the Coal and Biomass energy lab at Texas A&M reported that dairy biomass can be an effective Reburn fuel with NOX reduction of up to 95%; however little work has been done to model such a process with Feedlot Biomass as a blend with the main burner fuel. The present work concerns with development of a zero dimensional for a low NOx burner (LNB) model in order to predict NOX emissions while firing a blend of Coal and dairy biomass. Two models were developed. Model I assumes that the main burner fuel is completely oxidized to CO,CO2,H20 and fuel bound nitrogen is released as HCN, NH3, N2; these partially burnt product mixes with tertiary air, undergoes chemical reactions specified by kinetics and burns to complete combustion. Model II assumes that the main burner solid fuel along with primary and secondary air mixes gradually with recirculated gases, burn partially and the products from the main burner include partially burnt solid particles and fuel bound nitrogen partially converted to N2, HCN and NH3. These products mix gradually with tertiary air, undergo further oxidation-reduction reactions in order to complete the combustion. The results are based on model I. Results from the model were compared with experimental findings to validate it. Results from the model recommend the following conditions for optimal reduction of NOx: Equivalence Ratio should be above 0.95; mixing time should be below 100ms. Based on Model I, results indicate that increasing percentage of dairy biomass in the blend increases the NOx formation due to the assumption that fuel N compounds ( HCN, NH3) do not undergo oxidation in the main burner zone. Thus it is suggested that model II must be adopted in the future work.