47 research outputs found
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Treatment of Mercury Contaminated Oil from the Mound Site
Over one thousand gallons of tritiated oil, at various contamination levels, are stored in the Main Hill Tritium Facility at the Miamisburg Environmental Management Project (MEMP), commonly referred to as Mound Site. This tritiated oil is to be characterized for hazardous materials and radioactive contamination. Most of the hazardous materials are expected to be in the form of heavy metals, i.e., mercury, silver, lead, chromium, etc, but transuranic materials and PCBs could also be in some oils. Waste oils, found to contain heavy metals as well as being radioactively contaminated, are considered as mixed wastes and are controlled by Resource Conservation and Recovery Act (RCRA) regulations. The SAMMS (Self-Assembled Mercaptan on Mesoporous Silica) technology was developed by the Pacific Northwest National Laboratory (PNNL) for removal and stabilization of RCRA metals (i.e., lead, mercury, cadmium, silver, etc.) and for removal of mercury from organic solvents. The SAMMS material is based on self-assembly of functionalized monolayers on mesoporous oxide surfaces. The unique mesoporous oxide supports provide a high surface area, thereby enhancing the metal-loading capacity. SAMMS material has high flexibility in that it binds with different forms of mercury, including metallic, inorganic, organic, charged, and neutral compounds. The material removes mercury from both organic wastes, such as pump oils, and from aqueous wastes. Mercury-loaded SAMMS not only passes TCLP tests, but also has good long-term durability as a waste form because: (1) the covalent binding between mercury and SAMMS has good resistance in ion-exchange, oxidation, and hydrolysis over a wide pH range and (2) the uniform and small pore size of the mesoporous silica prevents bacteria from solubilizing the bound mercury
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A General Methodology for Evaluation of Carbon Sequestration Activities and Carbon Credits
A general methodology was developed for evaluation of carbon sequestration technologies. In this document, we provide a method that is quantitative, but is structured to give qualitative comparisons despite changes in detailed method parameters, i.e., it does not matter what ''grade'' a sequestration technology gets but a ''better'' technology should receive a better grade. To meet these objectives, we developed and elaborate on the following concepts: (1) All resources used in a sequestration activity should be reviewed by estimating the amount of greenhouse gas emissions for which they historically are responsible. We have done this by introducing a quantifier we term Full-Cycle Carbon Emissions, which is tied to the resource. (2) The future fate of sequestered carbon should be included in technology evaluations. We have addressed this by introducing a variable called Time-adjusted Value of Carbon Sequestration to weigh potential future releases of carbon, escaping the sequestered form. (3) The Figure of Merit of a sequestration technology should address the entire life-cycle of an activity. The figures of merit we have developed relate the investment made (carbon release during the construction phase) to the life-time sequestration capacity of the activity. To account for carbon flows that occur during different times of an activity we incorporate the Time Value of Carbon Flows. The methodology we have developed can be expanded to include financial, social, and long-term environmental aspects of a sequestration technology implementation. It does not rely on global atmospheric modeling efforts but is consistent with these efforts and could be combined with them
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Energy Production from Zoo Animal Wastes
Elephant and rhinoceros dung was used to investigate the feasibility of generating methane from the dung. The Knoxville Zoo produces 30 cubic yards (23 m{sup 3}) of herbivore dung per week and cost of disposal of this dung is $105/week. The majority of this dung originates from the Zoo's elephant and rhinoceros population. The estimated weight of the dung is 20 metric tons per week and the methane production potential determined in experiments was 0.033 L biogas/g dung (0.020 L CH{sub 4}/g dung), and the digestion of elephant dung was enhanced by the addition of ammonium nitrogen. Digestion was better overall at 37 C when compared to digestion at 50 C. Based on the amount of dung generated at the Knoxville Zoo, it is estimated that two standard garden grills could be operated 24 h per day using the gas from a digester treating 20 metric ton herbivore dung per week
Wolbachia Prophage DNA Adenine Methyltransferase Genes in Different Drosophila-Wolbachia Associations
Wolbachia is an obligatory intracellular bacterium which often manipulates the reproduction of its insect and isopod hosts. In contrast, Wolbachia is an essential symbiont in filarial nematodes. Lately, Wolbachia has been implicated in genomic imprinting of host DNA through cytosine methylation. The importance of DNA methylation in cell fate and biology calls for in depth studing of putative methylation-related genes. We present a molecular and phylogenetic analysis of a putative DNA adenine methyltransferase encoded by a prophage in the Wolbachia genome. Two slightly different copies of the gene, met1 and met2, exhibit a different distribution over various Wolbachia strains. The met2 gene is present in the majority of strains, in wAu, however, it contains a frameshift caused by a 2 bp deletion. Phylogenetic analysis of the met2 DNA sequences suggests a long association of the gene with the Wolbachia host strains. In addition, our analysis provides evidence for previously unnoticed multiple infections, the detection of which is critical for the molecular elucidation of modification and/or rescue mechanism of cytoplasmic incompatibility
The effect of a multi-component camp-based weight-loss program on children’s motor skills and physical fitness: a randomized controlled trial
Population genomics of the Wolbachia endosymbiont in Drosophila melanogaster
Wolbachia are maternally-inherited symbiotic bacteria commonly found in
arthropods, which are able to manipulate the reproduction of their host in
order to maximise their transmission. Here we use whole genome resequencing
data from 290 lines of Drosophila melanogaster from North America, Europe and
Africa to predict Wolbachia infection status, estimate cytoplasmic genome copy
number, and reconstruct Wolbachia and mtDNA genome sequences. Complete
Wolbachia and mitochondrial genomes show congruent phylogenies, consistent with
strict vertical transmission through the maternal cytoplasm and imperfect
transmission of Wolbachia. Bayesian phylogenetic analysis reveals that the most
recent common ancestor of all Wolbachia and mitochondrial genomes in D.
melanogaster dates to around 8,000 years ago. We find evidence for a recent
incomplete global replacement of ancestral Wolbachia and mtDNA lineages, which
is likely to be one of several similar incomplete replacement events that have
occurred since the out-of-Africa migration that allowed D. melanogaster to
colonize worldwide habitats.Comment: 41 pages, 5 figure
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OZONE TREATMENT OF SOLUBLE ORGANICS IN PRODUCED WATER
This project was an extension of previous research to improve the applicability of ozonation and will help address the petroleum-industry problem of treating produced water containing soluble organics. The goal of this project was to maximize oxidation of hexane-extractable organics during a single-pass operation. The project investigated: (1) oxidant production by electrochemical and sonochemical methods, (2) increasing the mass transfer rate in the reactor by forming microbubbles during ozone injection into the produced water, and (3) using ultraviolet irradiation to enhance the reaction if needed. Several types of methodologies for treatment of soluble organics in synthetic and actual produced waters have been performed. The technologies tested may be categorized as follows: (1) Destruction via sonochemical oxidation at different pH, salt concentration, ultraviolet irradiation, and ferrous iron concentrations. (2) Destruction via ozonation at different pH, salt concentration, hydrogen peroxide concentrations, ultraviolet irradiation, temperature, and reactor configurations
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OZONE TREATMENT OF SOLUBLE ORGANICS IN PRODUCED WATER (FEAC307)
Oil production is shifting from ''shallow'' wells (0-650 ft water depth) to off-shore, deep-water operations (>2,600 ft.). Production from these operations is now approaching 20%. By 2007, it is projected that as much as 70% of the U.S. oil production will be from deep-water operations. The crude oil from these deep wells is more polar, thus increasing the amount of dissolved hydrocarbons in the produced water. Early data from Gulf of Mexico (GOM) wells indicate that the problem with soluble organics will increase significantly as deep-water production increases. Existing physical/chemical treatment technologies used to remove dispersed oil from produced water will not remove dissolved organics. GOM operations are rapidly moving toward design of high-capacity platforms that will require compact, low-cost, efficient treatment processes to comply with current and future water quality regulations. This project is an extension of previous research to improve the applicability of ozonation and will help address the petroleum industry-wide problem of treating water containing soluble organics. The goal of this project is to maximize oxidation of water-soluble organics during a single-pass operation. The project investigates: (1) oxidant production by electrochemical and sonochemical methods, (2) increasing the mass transfer rate in the reactor by forming microbubbles during ozone injection into the produced water, and (3) using ultraviolet irradiation to enhance the reaction if needed. Industrial collaborators include Chevron, Shell, Phillips, BP Amoco, Statoil, and Marathon Oil through a joint project with the Petroleum Environmental Research Forum (PERF). The research and demonstration program consists of three phases: (1) Laboratory testing in batch reactors to compare effectiveness of organics destruction using corona discharge ozone generation methods with hydrogen peroxide generated sonochemically and to evaluate the enhancement of destruction by UV light and micro-bubble spraying. (2) Continuous-flow studies to determine the efficacy of various contactors, the dependency of organics destruction on process variables, and scale-up issues. (3) Field testing of a prototype system in close collaboration with an industrial partner to generate performance data suitable for scale-up and economic evaluation
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NITRO-HYDROLYSIS: AN ENERGY EFFICIENT SOURCE REDUCTION AND CHEMICAL PRODUCTION PROCESS FOR WASTEWATER TREATMENT PLANT BIOSOLIDS
The nitro-hydrolysis process has been demonstrated in the laboratory in batch tests on one municipal waste stream. This project was designed to take the next step toward commercialization for both industrial and municipal wastewater treatment facility (WWTF) by demonstrating the feasibility of the process on a small scale. In addition, a 1-lb/hr continuous treatment system was constructed at University of Tennessee to treat the Kuwahee WWTF (Knoxville, TN) sludge in future work. The nitro-hydrolysis work was conducted at University of Tennessee in the Chemical Engineering Department and the gas and liquid analysis were performed at Oak Ridge National Laboratory. Nitro-hydrolysis of sludge proved a very efficient way of reducing sludge volume, producing a treated solution which contained unreacted solids (probably inorganics such as sand and silt) that settled quickly. Formic acid was one of the main organic acid products of reaction when larger quantities of nitric acid were used in the nitrolysis. When less nitric acid was used formic acid was initially produced but was later consumed in the reactions. The other major organic acid produced was acetic acid which doubled in concentration during the reaction when larger quantities of nitric acid were used. Propionic acid and butyric acid were not produced or consumed in these experiments. It is projected that the commercial use of nitro-hydrolysis at municipal wastewater treatment plants alone would result in a total estimated energy savings of greater than 20 trillion Btu/yr. A net reduction of 415,000 metric tons of biosolids per year would be realized and an estimated annual cost reduction of $122M/yr