摘要 :
The long-term objective of this work is to develop a transformational energy production technology by insitu thermal treatment of a coal seam for the production of substitute natural gas (SNG) while leaving much of the coal as car...
展开
The long-term objective of this work is to develop a transformational energy production technology by insitu thermal treatment of a coal seam for the production of substitute natural gas (SNG) while leaving much of the coal as carbon in the ground. This process converts coal to a high-efficiency, low-GHG emitting gas fuel. It holds the potential of providing environmentally acceptable access to previously unusable coal resources. This topical report discusses the development of experimental capabilities, the collection of available data, and the development of simulation tools to obtain process thermo-chemical and geo-thermal parameters in preparation for the eventual demonstration in a coal seam. It also includes experimental and modeling studies of CO(sub 2) sequestration. Efforts focused on: Constructing a suite of three different coal pyrolysis reactors. These reactors offer the ability to gather heat transfer, mass transfer and kinetic data during coal pyrolysis under conditions that mimic in situ conditions (Subtask 6.1). Studying the operational parameters for various underground thermal treatment processes for oil shale and coal and completing a design matrix analysis for the underground coal thermal treatment (UCTT). This analysis yielded recommendations for terms of targeted coal rank, well orientation, rubblization, presence of oxygen, temperature, pressure, and heating sources (Subtask 6.2). Developing capabilities for simulating UCTT, including modifying the geometry as well as the solution algorithm to achieve long simulation times in a rubblized coal bed by resolving the convective channels occurring in the representative domain (Subtask 6.3). Studying the reactive behavior of carbon dioxide (CO(sub 2)) with limestone, sandstone, arkose (a more complex sandstone) and peridotite, including mineralogical changes and brine chemistry for the different initial rock compositions (Subtask 6.4). Arkose exhibited the highest tendency of participating in mineral reactions, which can be attributed to the geochemical complexity of its initial mineral assemblage. In experiments with limestone, continuous dissolution was observed with the release of CO(sub 2) gas, indicated by the increasing pressure in the reactor (formation of a gas chamber). This occurred due to the lack of any source of alkali to buffer the solution. Arkose has the geochemical complexity for permanent sequestration of CO(sub 2) as carbonates and is also relatively abundant.
收起
摘要 :
Although remarkable progress has been made in developing technologies for the clean and efficient utilization of coal, the biggest challenge in the utilization of coal is still the protection of the environment. Specifically, elec...
展开
Although remarkable progress has been made in developing technologies for the clean and efficient utilization of coal, the biggest challenge in the utilization of coal is still the protection of the environment. Specifically, electric utilities face increasingly stringent restriction on the emissions of NOx and SOx, new mercury emission standards, and mounting pressure for the mitigation of CO2 emissions, an environmental challenge that is greater than any they have previously faced. The Utah Clean Coal Program addressed issues related to innovations for existing power plants including retrofit technologies for carbon capture and sequestration (CCS) or green field plants with CCS. The Program focused on the following areas: simulation, mercury control, oxycoal combustion, gasification, sequestration, chemical looping combustion, materials investigations and student research experiences. The goal of this program was to begin to integrate the experimental and simulation activities and to partner with NETL researchers to integrate the Program's results with those at NETL, using simulation as the vehicle for integration and innovation.
收起
摘要 :
The author presents a modern approach to reach these goals of accuracy with a low error rate. The United States has a vast array of weapons that spend most of all of their life in storage. Then upon removal from storage are expect...
展开
The author presents a modern approach to reach these goals of accuracy with a low error rate. The United States has a vast array of weapons that spend most of all of their life in storage. Then upon removal from storage are expected of performing with high reliability of their designers. Weapons are made, procured, tracked, used and destroyed in lots. Lot sizes are statically chosen to posses certain characteristics. Periodically during the life of a lot of weapons sample is randomly selected for detail destructive analysis. If it fails test requirements the entire lot may have to be modified or destroyed. Once the lot has been identified all its members have to be located for the appropriate action. When weapons leave the factory they are identical and have known life expectancies. It is known that a variety of environmental factors temperature, humidity, shock, vibration, etc. affect the weapons' condition and ultimate life expectancies. The older a weapon is the more possible variation in storage condition exist and hence variation in its life expectancies. If individual storage environments could be tracked individual life expectancies could be determined. Weapons reaching near end-of-life could be designated for training and save the cost of de-milling.
收起
摘要 :
Microelectromechanical Systems or MEMS is a fabrication technology for creating mechanical devices on micron scale (1x10(exp-6) meters). But MEMS is more than miniaturization. By combining, photolithography, deposition, patterning...
展开
Microelectromechanical Systems or MEMS is a fabrication technology for creating mechanical devices on micron scale (1x10(exp-6) meters). But MEMS is more than miniaturization. By combining, photolithography, deposition, patterning and etching a fabrication technology has resulted for the production full-assembled, integrated electromechanical systems on a scale once reserved for electronic integrated circuits (IC). As the first M of MEMS implies, individual features are on the micron scale that is 10(exp-6) meters but the resulting systems can be several millimeters in size.
收起
摘要 :
The primary focus of this project has been to provide design input for the implementation of a suite of Reroute Advisory Tools (RAT), which was recommended for implementation earlier in this project. The goal of this suite of tool...
展开
The primary focus of this project has been to provide design input for the implementation of a suite of Reroute Advisory Tools (RAT), which was recommended for implementation earlier in this project. The goal of this suite of tools is to enhance the dissemination and use of ATCSCC Reroute Advisories to NAS Users. Two smaller tasks were also completed over the course of this project. The first was the development of a proposal for the design of Web-based summary reports for POET (the Post-Operations Evaluation Tool). The second was to provide design input to the COM Program on the CCFP (Collaborative Convective Forecast Product). All three of these focus areas support the development of new tools that offer the potential to significantly reduce departure delays, improve the planning and implementation of responses severe weather, better accommodate the priorities and constraints of NAS users, and reduce the workload of FAA traffic managers, freeing them up for other tasks.
收起
摘要 :
Complex physical phenomena often include features that span a wide range of211 spatial and temporal scales. Accurate simulation of such phenomena can be 211 difficult to obtain, and computations that are under-resolved can even ex...
展开
Complex physical phenomena often include features that span a wide range of211 spatial and temporal scales. Accurate simulation of such phenomena can be 211 difficult to obtain, and computations that are under-resolved can even exhibit 211 spurious features. While it is possible to resolve small scale features by 211 increasing the number of grid points, global grid refinement can quickly lead to 211 problems that are intractable, even on the largest available computing 211 facilities. These constraints are particularly severe for three dimensional 211 problems that involve complex physics. One way to achieve the needed resolution 211 is to refine the computational mesh locally, in only those regions where enhanced 211 resolution is required. Adaptive solution methods concentrate computational 211 effort in regions where it is most needed. These methods have been successfully 211 applied to a wide variety of problems in computational science and engineering. 211 Adaptive methods can be difficult to implement, prompting the development of 211 tools and environments to facilitate their use. To ensure that the results of 211 their efforts are useful, algorithm and tool developers must maintain close 211 communication with application specialists. Conversely it remains difficult for 211 application specialists who are unfamiliar with the methods to evaluate the trade-211 offs between the benefits of enhanced local resolution and the effort needed to 211 implement an adaptive solution method.
收起
摘要 :
A radiative transfer algorithm in the solar wavelengths for the NOAA POES AVHRR is presented for the cloud-free, marine atmosphere. This algorithm combines linearized, single-scattering theory with an estimate of bi-directional su...
展开
A radiative transfer algorithm in the solar wavelengths for the NOAA POES AVHRR is presented for the cloud-free, marine atmosphere. This algorithm combines linearized, single-scattering theory with an estimate of bi-directional surface reflectance. Phase functions are parameterized using an aerosol distribution model and the ratio of radiance values measured in channels 1 and 2 of the AVHRR. Automated cloud screening and sun glint removal is included. Retrieved satellite aerosol optical depth (AOD) is compared to surface measured sunphotometer AOD collected during the International Global Atmospheric Chemistry (IGAC) Project's Second Aerosol Characterization Experiment (ACE-2) from June 16 to July 25, 1997. The comparison data set has a correlation coefficient of 0.88 with a standard error of 0.02 at both channel 1 and 2 wavelengths. Regional aerosol properties are examined with an emphasis on the differences between the ACE-1, TARFOX and ACE-2 regions. ACE-1 and ACE-2 regions have strong modes at AOD at around 0.1, but ACE-2 tails toward higher values consistent with urban and dust aerosol intrusion. The TARFOX region has a noticeable mode at AOD around 0.2, but has significant spread of AOD values consistent with the varied aerosol constituents in that area.
收起
