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Methane Recovery from Animal Manures The Current Opportunities Casebook
No full textGrowth and concentration of the livestock industry create opportunities for the proper disposal of the large quantities of manures generated at dairy, swine, and poultry farms. Pollutants from unmanaged livestock wastes can degrade the environment, and methane emitted from decomposing manure may contribute to global climate change. One management system not only provides pollution prevention but also can convert a manure problem into a new profit center. Economic evaluations and case studies of operating systems indicate that the anaerobic digestion (AD) of livestock manures is a commercially available bioconversion technology with considerable potential for providing profitable coproducts, including a cost-effective renewable fuel for livestock production operations. This Casebook examines some of the current opportunities for the recovery of methane from the AD animal manures. U.S. livestock operations currently employ four types of anaerobic digester technology: slurry, plug-flow, complete-mix, and covered lagoon. An introduction to the engineering economies of these technologies is provided, and possible end-use applications for the methane gas generated by the digestion process are discussed. The economic evaluations are based on engineering studies of digesters that generate electricity from the recovered methane. Case studies of operating digesters, with project and maintenance histories and the operators ''lessons learned,'' are included as reality checks. Factors necessary for successful projects, as well as a list of reasons explaining why some AD projects fail, are provided. The role of farm management is key; not only must digesters be well engineered and built with high-quality components, they must also be sited at farms willing to incorporate the uncertainties of a new technology. More than two decades of research has provided much information about how manure can be converted to an energy source; however, the American farmer has not been motivated to adopt new practices. More cost-effective and easily managed manure management techniques are still needed to encourage farmers to use animal manure for conversion into energy and nutrients, especially for smaller farms. AD benefits farmers monetarily and mitigates possible manure pollution problems, thereby sustaining development while maintaining environmental quality. Moreover, rural economic development will benefit from the implicit multiplier effect resulting from jobs created by implementing digester systems. Promising future waste-to-profit activities may add to the economic performance of AD. New end-use applications, which provide added value to coproducts, are discussed
Joint U.S./Russian Study on the Development of a Preliminary Cost Estimate of the SAFSTOR Decommissioning Alternative for the Leningrad Nuclear Power Plant Unit #1
No full textThe objectives of the two joint Russian/U.S. Leningrad Nuclear Power Plant (NPP) Unit #1 studies were the development of a safe, technically feasible, economically acceptable decom missioning strategy, and the preliminary cost evaluation of the developed strategy. The first study, resulting in the decommissioning strategy, was performed in 1996 and 1997. The preliminary cost estimation study, described in this report, was performed in 1997 and 1998. The decommissioning strategy study included the analyses of three basic RBM.K decommission- ing alternatives, refined for the Leningrad NPP Unit #1. The analyses included analysis of the requirements for the planning and preparation as well as the decommissioning phases
Development of a Gas-Promoted Oil Agglomeration Process
No full textTwo series of agglomeration tests were conducted as part of an effort to find a suitable basis for size scale-up of the mixing system used for a gas-promoted oil agglomeration process. In the first series of tests the agitator impeller diameter and speed were varied among runs so as to vary impeller tip speed and agitator power independently while keeping other conditions constant. In the second series of tests the mixing tank size and agitator speed were varied while the ratio of tank diameter to impeller diameter were held constant. All tests were conducted with finely ground Pittsburgh No. 8 coal and with i-octane as the agglomerant. The results of these tests showed that the minimum time te required to produce spherical agglomerates was predominantly a function of the agitator power input per unit volume. In addition, the size of the agglomerates produced in a given time was also strongly dependent on power input. At lower power input levels, the mean size rose as power input increased until a point was reached where agglomerate breakage became important and the mean size decreased. The results also showed that the ash content of the agglomerates produced in a given time tended to decrease with increasing power input. On the other hand, the recovery of clean coal on a dry, ash-free basis was not greatly affected by power input
Supercritical Fluid Reactions for Coal Processing
No full textExciting opportunities exist for the application of supercritical fluid (SCF) reactions for the pre-treatment of coal. Utilizing reactants which resemble the organic nitrogen containing components of coal, we developed a method to tailor chemical reactions in supercritical fluid solvents for the specific application of coal denitrogenation. The tautomeric equilibrium of a Schiff base was chosen as one model system and was investigated in supercritical ethane and cosolvent modified supercritical ethane. The Diels-Alder reaction of anthracene and 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) was selected as a second model system, and it was investigated in supercritical carbon dioxide
Feasability of Optimizing Recovery and Reserves from a Mature and Geological Complex Multiple Turbidite Offshore California Reservoir Through the Drilling and Completion of a Trilateral Horizontal Well
No full textThe main objective of this project is to devise an effective redevelopment strategy to combat producibility problems related to the Repetto turbidite sequences of the Carpinteria Field. The lack of adequate reservoir characterization, high-water cut production, and scaling problems have in the past contributed to the field's low productivity. To improve productivity and enhance recoverable reserves, the following specific goals are proposed: ° Develop an integrated database of all existing data from work done by the former ownership group. ° Expand reservoir drainage and reduce sand problems through horizontal well drilling and completion. ° Operate and validate reservoirs conceptual model by incorporating new data from the proposed trilateral well. ° Transfer methodologies employed in geologic modeling and drilling multilateral wells to other operators with similar reservoirs
Task 6.7.3 - Interfacial Mass Transport Effects in Composite Materials
No full textAdvanced metal-matrix composites (MMCS) consisting of titanium-based alloys possess some unique mechanical, physical, and chemical characteristics that make them highly desirable for aircraft and gas turbine engines. Tailoring MMC properties is essential for advanced product design in materials processing. The main factors that affect materials processing and, further, the nature of a metal-ceramic interface, its structure, and morphological stability is liquid surface mass transport related to adhesional wetting (physical effect) and reactive wetting (chemical effect).' Surfaces and interfaces dominate many of the technologically important processes in composite materials such as liquid-solid sintering and joining. The objective of this work is threefold: 1) to get insight into the role of the nonstoichiometry of chemical composition in ceramic materials used as reinforcement components in MMC processing, 2) to extend previous energetic analysis of mass transport phenomena to wetting behavior between liquid metal and the quasi-solidlike skin resulting from the presolidification of liquid on nonstoichiometric solids on a scale of interatomic distance, and 3) to provide experimental verification of our concept
Application Guide to Neutron Multiplicity Counting
No full textThis document is intended to serve as a comprehensive applications guide to passive neutron multiplicity counting, a new nondestructive assay (NDA) technique developed over the past ten years. The document describes the principles of multiplicity counter design, electronics, and mathematics. Existing counters in Department of Energy (DOE) facilities are surveyed, and their operating requirements and procedures and defined. Current applications to plutonium material types found in DOE facilities are described, and estimates of the expected assay precision and bias are given. Lastly, guidelines for multiplicity counter selection and procurement are summarized. The document also includes a detailed collection of references on passive neutron coincidence and multiplicity publications over the last ten to fifteen years
Task 6.5/6.7.1 - Materials for Gas Separation and Hydrogen Separation Membranes
No full textCatalytic gasification of coal to produce H2- and CH4-rich gases for consumption in molten carbonate fuel cells is currently under development; however, to optimize the fuel cell performance and extend its operating life, it is desired to separate as much of the inerts as possible from the fuel gas before they enter the fuel cell. In addition, the economics of the integrated gasification combined cycle (IGCC) can be improved by separating as much of the hydrogen as possible from the fuel, since hydrogen is a high-value product. One process currently under development by the Energy & Environmental Research Center (EERC) for accomplishing this gas separation and hot-gas cleanup involves gas separation membranes. These membranes are operated at temperatures as high as 8000 C and pressures up to 300 psig. Some of these membranes can have very small pores (30-50 ~), which inefficiently separate the undesired gases by operating in the Knudsen diffusion region of mass transport. Other membranes with smaller pore sizes ( <5 ~) operate in the molecular sieving region of mass transport phenomena. Dissolution of atomic hydrogen into thin metallic membranes made of platinum and palladium alloys is also being developed. Technological and economic issues that must be resolved before gas separation membranes are commercially viable include improved gas separation efficiency, membrane optimization, sealing of membranes in pressure vessels, high burst strength of the ceramic material, pore thermal stability, and material chemical stability. Hydrogen separation is dependent on the temperature, pressure, pressure ratio across the membrane, and ratio of permeate flow to total flow
Proposed Utopia Bus Structure for OC192 Data Rates
No full textThis contribution proposes a 64 bit wide bus structure that will operate at rates inexcess of lO Gbps asa strawmanfora OC192c Utopia Specification
Preliminary Assessment of the Nuclide Migration from the Activation Zone Around the Proposed Spallation Neutron Source Facility
No full textThe purpose of this study is to investigate the potential impacts of migrating radionuclides from the activation zone around the proposed Spallation Neutron Source (SNS). Using conservatively high estimates of the potential inventory of radioactive activation products that could form in the proposed compacted-soil shield berm around an SNS facility on the Oak Ridge Reservation (ORR), a conservative, simplified transport model was used to estimate the potential worst-case concentrations of the 12 long-lived isotopes in the groundwater under a site with the hydrologic characteristics of the ORR. Of the 12, only 3 isotopes showed any potential to exceed the U.S. Nuclear Regulatory Commission (NRC) 10 Code of Federal Regulations (CFR) Part 20 Drinking Water Limits (DWLs). These isotopes were 14C, 22Na, and 54Mn. The latter two activation products have very short half-lives of 2.6 years and 0.854 year, respectively. Therefore, these will decay before reaching an off-site receptor, and they cannot pose off-site hazards. However, for this extremely conservative model, which overestimates the mobility of the contaminant, 14C, which has a 5,730-year half-life, was shown to represent a potential concern in the context of this study's conservative assumptions. This study examines alternative modifications to the SNS shield berm and makes recommendations