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A Satellite Workshop of the 14th International Congress on Photosynthesis on the topic of photosynthetic light-harvesting systems was held on 18-21 July 2007, at the Buchanan Arms Hotel in Drymen, Scotland, near Glasgow. This meeting continued the tradition of satellite light-harvesting conferences occurring prior to the last five international photosynthesis congresses in Japan, France, Hungary, Australia and Canada, dating from 1992. With an attendance of 124 participants, this Workshop represents an intimate gathering of scientists interested in a thorough coverage of the light-harvesting aspects of photosynthesis. A significant amount of time was set aside for discussion and poster sessions. The organizers were: Richard J. Cogdell, UK (Chairperson), Alastair T. Gardiner, UK, Conrad W. Mullineaux, UK, Robert A. Niederman, USA, Robert E. Blankenship, USA, Harry Frank, USA, Bruno Robert, France. Sessions were focused on new concepts relating to the function, regulation, assembly, photoprotection and evolution of a wide variety of antenna systems. Cutting-edge scientific methods used to study these systems that were covered included time-resolved and single-molecule spectroscopy, structure determination by X-ray diffraction, NMR and electron and atomic force microscopy, molecular genetics, protein chemistry, model systems and theory. A central theme was how emerging high-resolution structural information on antenna proteins continuesmore » to provide an enhanced understanding of areas ranging from the kinetics of energy transfer processes to the assembly of the photosynthetic apparatus.« less

Mercury emissions from coal fired plants will be limited by regulations enforced by the Environmental Protection Agency. However, there is still debate over whether the limits should be on a plant specific basis or a nationwide basis. The nationwide basis allows a Cap and Trade program similar to that for other air pollutants. Therefore, a major issue is the magnitude and extent of local deposition. Computer modeling suggests that increased local deposition will occur on a local (2 to 10 Km) to regional scale (20 to 50 Km) with the increase being a small percentage of background deposition on the regional scale. The amount of deposition depends upon many factors including emission rate, chemical form of mercury emitted (with reactive gaseous mercury depositing more readily than elemental mercury), other emission characteristics (stack height, exhaust temperature, etc), and meteorological conditions. Modeling suggests that wet deposition will lead to the highest deposition rates and that these will occur locally. Dry deposition is also predicted to deposit approximately the same amount of mass as wet deposition, but over a much greater area. Therefore, dry deposition rates will contribute a fraction of total deposition on the regional scale. The models have a number ofmore » assumptions pertaining to deposition parameters and there is uncertainty in the predicted deposition rates. A key assumption in the models is that the mixture of reactive gaseous mercury (RGM) to elemental mercury Hg(0) is constant in the exhaust plume. Recent work suggests that RGM converts to Hg(0) quickly. Deposition measurements around coal-fired power plants would help reduce the uncertainties in the models. A few studies have been performed to examine the deposition of mercury around point sources. Measurement of soil mercury downwind from chlor-alkali plants has shown increased deposition within a few Km. Studies of soils, sediments, and wet deposition around coal plants typically find some evidence of enhanced deposition; however, the statistical significance of the results is generally weak. A review of these studies is found in Lipfert. This study combines modeling of mercury deposition patterns with soil mercury measurements. The model used emissions data, meteorological conditions, and plant data to define sample locations likely to exhibit deposition in excess of background, that can be attributed to the power plant. Data were collected at the specified locations in November, 2003.« less

Early in FY04, the Advanced Nuclear Transformation Technology (ANTT) subcommittee of the Nuclear Energy Research Advisory Committee (NERAC) requested a report on repository benefits for recycling of key transuranics in existing light water-cooled reactors (LWRs). The ANTT reviewers specifically requested a quantification of how such a campaign would impact (improve) the achievable loading of nuclear waste in the Yucca Mountain facility. The request stipulated that the transuranics be separated from commercial spent nuclear fuel (CSNF) and recycled a finite number of times in LWR-compatible fuel forms. The spent fuel remaining at the end of the recycling campaign, as well as all other nuclear waste generated by spent fuel reprocessing, would be permanently disposed in a geologic repository. In response, two reports have been prepared and distributed as deliverables for the AFCI program. Reference 1 provides the final report which addresses the original ANTT sub-committee request. Plutonium, neptunium, and americium recycling strategies in assemblies fabricated from mixed-oxide (MOX), CORAIL (heterogeneous UO{sub 2} and MOX), and inert-matrix fuel (IMF) forms were evaluated; the focus of the report is the time-dependent thermal response of the repository to a given loading of nuclear waste in the storage tunnels (drifts), as well as a quantificationmore » of how the loading could be increased relative to the reference direct disposal of CSNF. Reference 2 provides a more complete description of the neutronics and mass flow analyses which were completed as part of the study. That report also provides an analysis of the differences between the various recycling strategies and the underlying reactor physics.« less

The Thermogravimetric Analyzer-Fourier Transform Infrared Spectrometer-Mass Spectrometer (TG-FTIR-MS) system was used to identify molecular chlorine, along with HCl, CO, CO{sub 2}, H{sub 2}O, and various hydrocarbons in the gaseous products of the combustion of PVC resin in air. This is a significant finding that will lead us to examine this combustion step further to look for the formation of chlorinated organic compounds. The combination of TG-FTIR and TG-MS offers complementary techniques for the detection and identification of combustion products from coals PVC, cellulose, shredded newspaper, and various blends of these materials. The pilot atmospheric fluidized bed combustor (AFBC) at Western Kentucky University has been tested. The main purpose of these preliminary AFBC runs were to determine the compatibility of coal and pelletized wood in blends and to explore the effects of flue/air ratio. Our objective is to conduct AFBC burns with 90 percent sulfur capture and more then 96% combustion efficiency.

In support of studies for developing the coprocessing of fossil fuels with biomass by the Hydrocarb Process, experimental and process design data are reported. The experimental work includes the hydropryolysis of biomass and the thermal decomposition of methane in a tubular reactor. The rates of reaction and conversion were obtained at temperature and pressure conditions pertaining to a Hydrocarb Process design. A Process Simulation Computer Model was used to design the process and obtain complete energy and mass balances. Multiple feedstocks including biomass with natural gas and biomass with coal were evaluated. Additional feedstocks including green waste, sewage sludge and digester gas were also evaluated for a pilot plant unit.

This project encompassed the design, development, and demonstration of integrated online optimization systems at Dynegy Midwest Generation's Baldwin Energy Complex (BEC) located in Baldwin, Illinois. The overall project objective was to improve coal-based generation's emission profile, efficiency, maintenance requirements and plant asset life in order to enhance the long-term viability of the United States abundant coal resources. Five separate but integrated optimization products were developed, addressing combustion, sootblowing, SCR operations, overall unit thermal performance, and plant-wide availability optimization. Optimization results are inherently unit-specific and cannot be known for a particular generating unit in advance. However, NeuCo believed that the following were reasonable targets for the completed, integrated set of products: Furnace NOx reduction improvement by 5%, Heat rate improvement by 1.5%, Increase of annual Available MWh by 1.5%, Commensurate reductions in greenhouse gases, mercury, and particulates; and Commensurate increases in profitability from lower costs, improved reliability, and greater commercial availability. The goal during Phase I was to establish each system and demonstrate their integration in unified plant optimization. Efforts during Phase I focused on: (1) developing, deploying, integrating, and testing prototypes for each of the five products; (2) identifying and addressing issues required for the products to integrate with plant operations; and (3) systematically collecting and assimilating feedback to improve subsequent product releases. As described in the Phase II continuation application NeuCo successfully achieved the goal for Phase I. The goal of Phase II was to improve upon the products installed and tested in Phase I and to quantify the benefits of the integrated system. As this report documents, NeuCo has also successfully achieved the goal for Phase II. The overall results of the project, compared with the project goals, are: (1) NOx Reduction: The 5% target for NOx reduction was exceeded with average CEMS and SCR Inlet (furnace) NOx reduction of between 12% and 14%. (2) Heat Rate Improvement: The optimization systems delivered an average heat rate improvement of between 0.67% and 0.7%. This falls short of the 1.5% heat rate improvement target largely because Cyclone Stability (availability) and CEMS and SCR Inlet NOx were prioritized over heat rate in the event they needed to be traded-off with one another. A different prioritization of objectives could have driven a different balance, thereby meeting the target of 1.5% improvement. There were also several factors that could have been masking greater heat rate improvements such as the decrease in fuel density over the course of the project and the impact of actions taken as a result of advice provided by the optimizers that are difficult to quantify. (3) Increased Annual Available MWh: Although difficult to measure precisely, the target of increasing available MWh's by 1.5% was met by providing prioritized alerts and knowledge-based diagnostics for a wide array of plant equipment and process anomalies; helping the plant to move from high sulfur, high Btu Illinois coal to PRB and run that fuel at low stoichiometries without derates; and improved management of cyclone flame quality as well as improved vigilance with respect to cyclone conditions which avoided some degree of temporary de-rate due to cyclone slag build up. (4) Commensurate Reductions in Greenhouse Gases, Mercury, and Particulates: Reductions in all three of these indices can be associated directly with the optimization leverage observed in the heat rate and NOx reductions. (5) Commensurate Increases in Profitability from Lower Costs, Improved Reliability, and Greater Commercial Availability: Commensurate improvements in costs, reliability and availability resulted from the previously described benefits. Also playing a role were the sustained operation of the cyclones while using more available, less expensive but off-design fuel; more effective catalytic reduction of NOx; and the reduced time required to discover, prioritize and diagnose plant equipment issues. The total annual dollar value of the benefits associated with the products installed, refined, and commercialized at BEC are estimated to range from $1.8 to $3.2 million dollars per-unit, and $7.2 to $8.1 million dollars per year plant-wide depending on whether CO{sub 2} benefits are included. In summary, the NeuCo project at BEC was successfully completed and has demonstrated that advanced optimization technologies can play an important role in improving the environmental footprint of coal-based power generation while achieving other important operating objectives.

The Iraqi invasion of Kuwait and the subsequent war between Iraq and an international alliance led by the United States triggered immediate increases in world oil prices. Increases in world petroleum prices and in US petroleum imports resulted in higher petroleum prices for US customers. In this report, the effects of the Persian Gulf War and its aftermath are used to demonstrate the potential impacts of petroleum price changes on majority, black, and Hispanic households, as well as on poor and nonpoor households. The analysis is done by using the Minority Energy Assessment Model developed by Argonne National Laboratory for the US Department of Energy (DOE). The differential impacts of these price increases and fluctuations on poor and minority households raise significant issues for a variety of government agencies, including DOE. Although the Persian Gulf crisis is now over and world oil prices have returned to their prewar levels, the differential impacts of rising energy prices on poor and minority households as a result of any future crisis in the world oil market remains a significant long-term issue.

Abstract Measurements of sorption isotherms and transport properties of CO2 in coal cores are important for designing enhanced coalbed methane/CO2 sequestration field projects. Sorption isotherms measured in the lab can provide the upper limit on the amount of CO2 that might be sorbed in these projects. Because sequestration sites will most likely be in unmineable coals, many of the coals will be deep and under considerable lithostatic and hydrostatic pressures. These lithostatic pressures may significantly reduce the sorption capacities and/or transport rates. Consequently, we have studied apparent sorption and diffusion in a coal core under confining pressure. A core from the important bituminous coal Pittsburgh #8 was kept under a constant, threedimensional external stress; the sample was scanned by X-ray computer tomography (CT) before, then while it sorbed, CO2. Increases in sample density due to sorption were calculated from the CT images. Moreover, density distributions for small volume elements inside the core were calculated and analyzed. Qualitatively, the computerized tomography showed that gas sorption advanced at different rates in different regions of the core, and that diffusion and sorption progressed slowly. The amounts of CO2 sorbed were plotted vs. position (at fixed times) and vs. time (for various locations in the sample). The resulting sorption isotherms were compared to isotherms obtained from powdered coal from the same Pittsburgh #8 extended sample. The results showed that for this single coal at specified times, the apparent sorption isotherms were dependent on position of the volume element in the core and the distance from the CO2 source. Also, the calculated isotherms showed that less CO2 was sorbed than by a powdered (and unconfined) sample of the coal. Changes in density distributions during the experiment were also observed. After desorption, the density distribution of calculated volume elements differed from the initial distribution, suggesting hysteresis and a possible rearrangement of coal structure due to CO2 sorption.