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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
311

Wastewater treatment alternatives for a vegetable and seafood cannery

Grassiano, James W. 08 June 2009 (has links)
Peeled or whole-pack tomatoes, herring roe and oysters are processed at a Virginia Cannery. Wastewater from each food processing effluent was characterized. Treatment alternatives were investigated for tomato and herring roe wastewaters. For herring roe processing wastewater, the discharge requirement for BOD was nearly met through plain settling, while the TSS limitation was easily achieved by settling out the roe particles" Oyster processing wastewater was found to meet effluent guidelines without treatment. Bench-scale treatability studies were performed using sequencing batch reactors (SBRs) to treat the segregated wastewater from the caustic tomato peeling operation. This isolated 98% of sodium present in the wastewater. Previously, all wastewater was land applied and the high sodium content damaged soil structure. Sodium levels in monitoring wells below the irrigation field have risen, approaching regulated values. Results indicated that SBRs can be effective in reducing BOD and TSS to discharge requirements. BOD and TSS removals were well in excess of 90%. Initial values for BOD and TSS were 21,400 mg/l and 14,000 mg/l, respectively. Although conventional food to microorganism ratios were used, relatively long hydraulic retention times of 8 to 20 days were required to accomplish adequate BOD removal. Screening was found to be an effective form of pretreatment to remove large quantities of TSS. It appears practical to treat the tomato peeling wastewater by means of sludge drying beds. Approximately 0.5 acre of land would be required for bed construction. Final disposal costs associated with landfilling the dried sludge may govern whether sludge drying beds or an SBR should be used. In an effort to eliminate wastewater problems associated with the caustic peeling operation, an enzyme peeling study was performed using pectinase. Peeling ability of the enzyme was not as good as that of caustic, however, further investigation into alternative peeling operations is warranted due to the adverse effects of caustic materials on wastewater treatment alternatives. / Master of Science
312

Regional Jointing Pattern Within the Surficial Glacial Sediments and Bedrock of South-Central Ontario

Daniel, Sheila Ellen 03 1900 (has links)
<p> There is mounting pressure to find suitable disposal sites for both household and industrial waste in south-central Ontario as a solution to Metropolitan Toronto's growing 'garbage crisis'. New data indicate that the fine-grained glacial sediments of south-central Ontario, previously considered to be 'tight' and impermeable, are in fact penetrated by an extensive joint system. This thesis provides basic information regarding the regional character, orientation and origin of joints within the surficial glacial sediments and bedrock of south-central Ontario. Three regional joint sets can be identified. Within the bedrock, the joint sets are oriented northeast/southwest, northwest/southeast and north/south. This trend is consistent with the regional jointing pattern within the overlying glacial sediments and suggests that the joints may have propagated from the bedrock into the glacial sediments. A comparison between the regional jointing pattern identified in bedrock and glacial materials and the orientation of stress release structures suggests that the regional pattern of jointing is controlled by the regional stress field which results from intraplate tectonic stresses. However, the orientation of joints at any individual site may also be controlled by 'local' factors such as face orientation, direction of glacial ice movement and lithology and by randomly oriented joints formed as the result of physical and chemical weathering, synaeresis, subglacial deformation and stress relief. The identification of regional jointing pattern within south-central Ontario allows the prediction of joint characteristics and orientations at potential landfill sites in the region, critical to the accurate evaluation of the permeability of the substrate materials.</p> / Thesis / Master of Science (MSc)
313

Creep Performance and Analysis of Buffer Material in a Nuclear Waste Disposal Vault

Yiotis, Demosthenes 08 1900 (has links)
No description available.
314

A Computer Simulation of the Operations of a Spent Nuclear Fuel Receiving and Storage Station

Barnard, Jeanna Lorene 01 July 1980 (has links) (PDF)
Spent nuclear fuel is received at a storage facility in heavily shielded casks transported by either rail or by truck. Once at the storage facility, the casks are inspected, emptied, decontaminated, and reshipped. Allied-General Nuclear Services' (AGNS) nuclear fuel reprocessing plant in Barnwell, South Carolina, is constructed but not yet licensed for spent nuclear fuel storage or reprocessing. Recently, however, AGNS was granted funds by the Department of Energy to prepare the necessary procedural and regulatory paperwork in order that the Fuel Receiving and Storage Station (FRSS) of the plant can be licensed by 1985. In this paper, the activities involved in the receiving an unloading of casks at the Barnwell FRSS is simulated by computer using IBM's program software package, General Purpose Simulation System (GPSS). The GPSS model is developed and verified, and steady-state output statistics are achieved. Also, several sensitivity analyses are performed such as, changes in expected arrival schedules and decision policies, and changes to the physical characteristics of the existing FRSS to monitor the effect of these changes in the existing system.
315

Environmental Aspects of the Nuclear Fuel Cycle and High-Level Radioactive Waste Disposal

Kent, Robert S. 01 April 1979 (has links) (PDF)
An assessment of the environmental effects of the nuclear fuel cycle industries is discussed, reactor waste inventory and standards are presented, and the alternatives for high-level radioactive waste disposal reviewed, with particular attention being given to disposal in deep geological formations on land. One of the major concerns regarding potential impacts of the nuclear fuel cycle industries is the lack of a definite and proven method of disposal of the high-level radioactive wastes from light water moderated reactors. The problem is expected to become more pressing as the nuclear power industry and the associated radioactive waste inventories grow in the strife to meet ever-increasing demands for energy. The current trend in waste management is towards reprocessing to recover unburned uranium and plutonium from spent reactor fuel and towards final disposal in deep geological formations (hard rock or salt) on land. Studies appear to support the viability of such a waste management and disposal concept for high-level radioactive wastes.
316

Signs of dangerdangerous signs : responding to nuclear threat

Van Wyck, Peter C. January 1997 (has links)
No description available.
317

Wet air oxidation of benzene

Abussaud, Basim Ahmed January 2007 (has links)
No description available.
318

A pilot plant study of the anaerobic digestion of semi-chemical mill wastes

Hild, Joseph Charles 23 February 2010 (has links)
The purpose of this investigation was to determine if high loadings of semi-chemical pulp mill waste could be processed in a pilot plant by anaerobic digestion. / Master of Science
319

Analysis by simulation of the disposition of nuclear fuel waste

Turek, Jeffery Lee January 1980 (has links)
To achieve the non-proliferation objectives of the United States, the reprocessing of spent nuclear fuel was discontinued in 1977. Since current at-reactor storage capacity is based upon a nuclear fuel cycle which includes reprocessing, this halt in reprocessing is causing large quantities of non-storable spent fuel. Permanent nuclear waste storage repositories will not be available until the end of the century. Present Department of Energy policy calls for sufficient interim Away-Prom-Reactor (AFR) Storage capacity to insure tilat no commercial reactor has to shut down due to inadequate storage space for discharged spent fuel. A descriptive simulation model is developed which includes all aspects of nuclear waste disposition. The model is comprised of two systems, the second system orchestrated by GASP IV. A spent fuel generation prediction module is interfaced with the AFR Program Management Information System and a repository scheduling information module. The user is permitted a wide range of options with which to tailor the simulation to any desired storage scenario. The model projects storage requirements through the year 2020. The outputs are evaluations of the impact that alternative decision policies and milestone date changes have on the demand for, the availability of, and the utilization of spent fuel storage capacities. Both graphs and detailed listings are available. These outputs give a comprehensive view of the particular scenario under observation, including the tracking, by year, discharge from every reactor. Included within the work is a review of the status of spent fuel disposition based on input data accurate as of August 1980. The results indicate that some temporary storage techniques (e.g., transshipment of fuel and/or additional at-reactor storage pools) must be utilized to prevent reactor shutdowns. These techniques will be required until the 1990’s when several AFR facilities, and possibly one repository, can become operational. / Ph. D.
320

An active landfill design for indefinite waste storage

Gillispie, Emmett Davidson January 1986 (has links)
The design characteristics of an active waste disposal capsule placed within a saturated groundwater environment is investigated, with the objective of developing a methodology to determine environmentally, technically and economically feasible conditions for its operation. In operation, conditions are created and maintained within and surrounding a containment cell to insure that a potential for convective inflow exists everywhere across an encapsulating barrier which tends to counter the potential for outward dispersion through the barrier. A computer algorithm based on the finite element method has been developed in the BASIC language to aid in the hydraulic analysis. Essentially, it provides a numerical solution to potential flow through porous media for two dimensional anisotropic solution domains of various materials. Data generated from this algorithm for cases of varying geometric material and boundary properties are used to verify and quantify assumed relationships involving critical design parameters which have been developed through dimensional analysis and physical reasoning. An expression describing the concentration profiles developed across the barrier is obtained by solving the one-dimensional convection-dispersion equation for steady conditions within and bounding the capsule barrier. Applying this result to an identified critical point allows conservative barrier design criteria to be developed so that operation of the active capsule results in only negligibly small amounts of contamination escaping through the barrier to the environment. By introducing cost coefficients which are descriptive of various aspects of construction, operation and maintenance of the active capsule, a total cost function is formulated from which, when minimized with respect to various design variables, optimizing criteria are developed. Finally, a predictor-corrector optimization program which incorporates the results of this study is developed and used to investigate an illustrative problem. / M.S.

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