Outplayed: Regaining Strategic Initiative in the Gray Zone, A Report Sponsored by the Army Capabilities Integration Center in Coordination with Joint Staff J-39/Strategic Multi-Layer Assessment Branch

U.S. competitors pursuing meaningful revision or rejection of the current U.S.-led status quo are employing a host of hybrid methods to advance and secure interests contrary to those of the United States. These challengers employ unique combinations of influence, intimidation, coercion, and aggression to incrementally crowd out effective resistance, establish local or regional advantage, and manipulate risk perceptions in their favor. So far, the United States has not come up with a coherent countervailing approach. It is in this “gray zone”—the awkward and uncomfortable space between traditional conceptions of war and peace—where the United States and its defense enterprise face systemic challenges to U.S. position and authority. Gray zone competition and conflict present fundamental challenges to U.S. and partner security and, consequently, should be important pacers for U.S. defense strategy.https://press.armywarcollege.edu/monographs/1924/thumbnail.jp

Reduction of inherent mercury emissions in PC combustion. Semi-annual technical progress report No. 2, January 1, 1996--June 30, 1996

The 1990 Clean Air Act Amendments handed the utility industry a major challenge for the coming years. The legislation requires that the U.S. Environmental Protection Agency set emission standards for the 189 compounds or compound families identified in the act as air toxics. Evaluations by EPRI have identified 37 of these species as concerns in power generation. This research focuses on the air pollution control of mercury and rate limiting steps in mercury capture

Suppression of fine ash formation in pulverized coal flames. Quarterly technical progress report No. 5, October 1, 1993--December 31, 1993

Laboratory work and studies of full-scale coal-fired boilers have identified two general mechanisms for ash production. The vast majority of the ash is formed from mineral matter that coalesces as the char burns, yielding particles that are normally larger than 0.5{mu}m. Flagen and Friedlander proposed a simple model for this residual ash, called the breakup model. The second major mechanism is the generation of a submicron aerosol through a vaporization/condensation mechanism. When the ash size distribution is plotted in terms of number density, the submicron mode generally peaks at about 0.1 {mu}/m. When plotted in terms of mass, this mode is sometimes distinct from the residual ash mode, {sup 13} and sometimes merged into it. Although these particles represent a relatively small fraction of the mass, they can present a large fraction of the surface area. Thus, they are a preferred site for the condensation of the more volatile oxides later in the furnace. This leads to a layering effect in which the refractory oxides are concentrated at the particle core and the more volatile oxides reside at the surface. This also explains the enrichment of the aerosol by volatile oxides that has been noted in samples from practical furnaces. These volatile metal oxides include the majority of the toxic metal contaminants, e.g., mercury, arsenic, selenium and nickel. Risk assessment studies suggest that toxic metal emissions represent a significant portion of the health risk associated with combustion

Suppression of fine ash formation in pulverized coal flames. Quarterly technical progress report No. 4, July 1, 1993--September 30, 1993

Laboratory work and studies of full-scale coal-fired boilers have identified two general mechanisms for ash production. The vast majority of the ash is formed from mineral matter that coalesces as the char burns, yielding particles that are normally larger than 0.5 {mu}m. The second major mechanism is the generation of a submicron aerosol through a vaporization/condensation mechanism. Previous work has shown that pulverized bituminous coals that were treated by coal cleaning (via froth flotation) or aerodynamic sizing exhibited altered aerosol emission characteristics. Specifically, the emissions of aerosol for the cleaned and sized coals increased by as much as one order of magnitude. The goals of the present progress are to: (1) perform measurements on carefully characterized coals to identify the means by which the coal treatment increases aerosol yields; (2) investigate means by which coal cleaning can be done in a way that will not increase aerosol yields; (3) identify whether this mechanism can be used to reduce aerosol yields from systems burning straight coal. This paper discusses model description and model formulation, and reports on the progress of furnace design and construction, and coal selection

Mechanisms governing fine particulate emissions from coal flames. Quarterly technical progress report No. 5, October 1, 1988--December 31, 1988

The overall objectives of this project are to provide a basic understanding of the principal processes that govern fine particulate formation in pulverized coal flames. This understanding is to be used to develop a model (or models) which will predict the yield and size distribution of fine particulates as a function of coal type, coal processing, and combustion conditions. The goal of the model is to provide an engineering tool that will enable the practitioner to estimate the consequences of design decisions and fuel selection on the fine particulate yield. The practitioner can then make rational decisions regarding the required technology and costs associated with effluent cleanup while still in the design phase

Mechanisms governing fine particulate emissions from coal flames. Quarterly technical progress report No. 6, January 1, 1989--March 31, 1989

The overall objective of this project is to provide a basic understanding of the principal processes that govern fine particulate formation in pulverized coal flames. This understanding is to be sued to develop a model (or models) which will predict the yield and size distribution of fine particulate matter as a function of coal type, coal processing, and combustion conditions. The goal of the model is to provide an engineering tool that will enable the practitioner to estimate the consequences of deign decisions and fuel selection on the fine particulate yield. The practitioner can then make rational decisions regarding the required technology and costs associated with effluent cleanup while still in the design phase

Mechanisms governing fine particulate emissions from coal flames. Quarterly technical progress report No. 7, April 1, 1989--June 31, 1989

The principal activities during this quarter involved the global experiments. Ash was sampled from a number of coals (of varying rank) as a function of oxygen concentration. Proximate analyses of the coals were performed. Analyses of the data were performed using the breakup model. When fitting the data with the breakup model, higher rank coals were found to require fewer ash particles per coal particle than the lower ranked coals. Deviations of the measured size distribution from the simple breakup model were examined. During this quarter preparation for the mechanistic experiments was begun. This work involves cleaning and sizing three coals and measuring the particle size distribution of ashes from these various cuts of coals. This work will continue during the next reporting quarter

Mechanisms governing fine particulate emissions from coal flames. Quarterly technical progress report No. 8, July 1, 1989--September 30, 1989

During this reporting period the global experiments were concluded. The final activities under these experiments involved measuring mineral content of coals as a function of coal particle size. The principal activities during this quarter involved the mechanistic experiments. Three baseline coals were cleaned and two of these sized. The ash from these various cuts were sampled from a bench scale reactor. The ash size distributions were compared to distributions predicted by the breakup model

Mechanisms governing fine particulate emissions from coal flames. Quarterly technical progress reports Nos. 3 and 4, April 1, 1988--September 30, 1988

The overall objectives of this project are to provide a basic understanding of the principal processes that govern fine particulate formation in pulverized coal flames, and develop procedures to predict the levels of emission of fine particles from pulverized coal combustors. (VC

Mechanisms governing fine particulate emissions from coal flames. Quarterly technical progress report No. 2, January 1, 1988--March 31, 1988

Efforts in this period focused on refining the plans for engineering analysis and fundamental experiments based on the results of a literature review, and modifying the Malvern laser diffraction particle sizer to operate at particle sizes down to 0.5 microns. The engineering analysis plan is to concentrate on development of new models and adaptation of existing models for fine particulate formation by three categories of mechanisms: particle breakup/ash coalescence; direct passage, fragmentation, or agglomeration of extraneous mineral matter; and bubble formation/breakup. The plan for fundamental experiments is to develop a fast, online, optical particle sizing technique which will span the 0.5 to 10 micron size range of interest; to perform global experiments to identify the important parameters affecting fine particle formation; and to perform mechanistic experiments to test specific hypotheses about the mechanisms which control fine particle formation in coal combustion