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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.
11

Dissolved oxygen dynamics in the Carson River, Nevada

Latham, Zachary B. January 2005 (has links)
Thesis (M.S.)--University of Nevada, Reno, 2005. / "December, 2005." Includes bibliographical references (leaves 125-128). Online version available on the World Wide Web.
12

Modeling the impact of logging debris on the dissolved oxygen balance of small mountain streams /

Berry, John David. January 1974 (has links)
Thesis (M.S.)--Oregon State University, 1975. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.
13

Relationships of dissolved oxygen and biochemical oxygen demand in sewage effluent releases

Sebenik, Paul Gregory, 1941- January 1975 (has links)
No description available.
14

Mediated biochemical oxygen demand biosensors for pulp mill wastewaters

Trosok, Steve Peter Matyas. January 2000 (has links)
Mediated microbial sensors utilizing two different yeast isolates (SPT1 and SPT2) were developed for the estimation of biochemical oxygen demand (BOD). Measurements of glucose/glutamic acid (GGA) standard solution with potassium ferricyanide mediation resulted in linear ranges extending from the detection limits (i.e. 2 and 5 ppm BOD) to 100 and 200 ppm BOD for the SPT1- and SPT2-based sensors, respectively. The standard error of the mean (SEW for 10 ppm. BOD measurements was 10.1% (SPT1) and 3.9% (SPT2). Response reproducibility had 10.6% error between three identically prepared SPT1 sensors. Response times for concentrations of 20 ppm BOD were within 10 minutes. For pulp mill effluent, the detection limits were 2 (SPT1) and 1 (SPT2) ppm BOD, with SEMs of 3.6% and 14.3% for the SPT1 and SPT2 sensors, respectively. Based on the results obtained in this study, it is concluded that SPT2 is the more suitable biocatalyst for pulp mill wastewater analysis. / While 18S rRNA gene sequence analyses, including BLAST homology searches, have suggested that isolate SPT1 is a close relative of Candida sojae (99.8% homology), no close matches have been found for isolate SPT2. The closest match for SPT2 was to Candida krusei (76.0% homology). Evidence from biochemical tests, fatty acid analysis, and 18S rRNA gene sequence analyses, indicates that isolate SPT2 is a novel yeast species.
15

An evaluation of the accuracy of biochemical oxygen demand and suspended solids analyses as performed by Wisconsin laboratories

Weber, Susan. January 1978 (has links)
Thesis (M.S.)--Wisconsin. / Includes bibliographical references (leaf 54).
16

Identification of Acid Volatile Sulfides as a Predictor of Sediment Oxygen Demand and Comparison of the Degree of Pyritization between Weeks Bay, AL and Old Tampa Bay, FL

Anderson, Erin Leigh 17 August 2013 (has links)
Weeks Bay, AL is a governmentally protected reserve near Mobile Bay, AL, while Old Tampa Bay, FL is an urbanized estuary, located along the western coast of Florida. Estuary health is important to local economies and the health of local marine life, with an emphasis on low levels of eutrophication. Sediment oxygen demand (SOD) is usually measured to qualify the environmental health of estuaries, but SOD is timeconsuming and expensive. Average acid volatile monosulfides (AVS) concentrations were found to accurately predict SOD variances. The Degree of Pyritization (DOP) is a measure of long-term sediment oxidation conditions, which indicates normal estuary state. Despite the urban land use practices of these two bays, the DOP of each bay is similar.
17

Mediated biochemical oxygen demand biosensors for pulp mill wastewaters

Trosok, Steve Peter Matyas. January 2000 (has links)
No description available.
18

Advancing the Treatment of Industrial Wastewater via Integration of PeCOD® And LC-OCD Analytical Tools

Aghasadeghi, Kimia January 2017 (has links)
In 2012, mandatory effluent quality standards were established in Canada as part of the Wastewater Systems Effluent Regulations (WSER) with compliance deadlines starting in 2020. Maintaining the treatment process efficacy to meet these new stringent discharge regulations is extremely challenging at treatment facilities that treat wastewater from multiple industries due to the high variation in the composition of the incoming feed to the process. In this work, application of two new analytical tools, PeCOD® and Liquid Chromatography-Organic Carbon Detection (LC-OCD), for measurement and characterization of industrial wastewater organic pollution respectively, has been investigated. Organic pollution is commonly measured as Chemical Oxygen Demand via the dichromate method (CODCr) which requires 2-3 hours to complete. Thus this method is not suitable for applications that require rapid and frequent pollution monitoring. The Photoelectrochemical Oxygen Demand (peCOD) is an alternative parameter of organic pollution that can be measured in approximately 15 minutes via a method that utilizes the high oxidation potential of UV-irradiated TiO2 nano-particulates. Herein peCOD suitability to replace CODCr for analysis of industrial wastewater was investigated. The results indicated that for both untreated (i.e. incoming) and treated (i.e. effluent) industrial wastewater samples, peCOD results are lower than CODCr results. However, for the effluent samples, the two methods’ results are strongly correlated. Containing hard to oxidize materials (i.e. macromolecules) and high concentrations of chloride and nitrogenous compounds were identified as potential causes of difference between the results of the two methods. When there is variation in the composition of the incoming wastewater to a treatment process, information about the wastewater composition is required for process optimization. Thus optimization cannot be based solely on bulk measurements of organic pollution (e.g. COD). In this study, a novel combination of LC-OCD analysis with Design-Of-Experiments (DOE) methods was used to optimize the Fenton Advanced Oxidation (AO) treatment conditions in terms of chemical reagent concentrations, to develop statistical models of the process, and to identify potential mechanisms of COD removal. / Thesis / Master of Applied Science (MASc) / Many industrial facilities do not treat their wastewater on-site and instead ship it to specialized treatment facilities. Ensuring that the treated effluent meets the stringent discharge regulations is a challenging task for such facilities as the composition of the incoming feed to the treatment process changes with each shipment. In this work, application of two new analytical tools, PeCOD® and Liquid Chromatography-Organic Carbon Detection (LC-OCD), for measurement and characterization of industrial wastewater organic pollution respectively, has been investigated. The conventional method of measuring organic pollution, Chemical Oxygen Demand (COD), requires 2-3 hours to complete. Herein the suitability of an alternative parameter, Photoelectrochemical Oxygen Demand (peCOD), that can be measured in approximately 15 minutes for replacing COD analysis in industrial wastewater plants was investigated. Implementation of effective treatment processes that are operated at their optimum conditions is required to meet the stringent discharge regulations. Advanced Oxidation (AO) is an effective method of industrial wastewater treatment. Herein, optimum AO treatment conditions were studied via application of the LC-OCD analysis for organic pollution characterization.
19

A laboratory study of reduction of the biochemical oxygen demand of synthetic sewage by Zoogloea ramigera

Thompson, Edwin E. January 1951 (has links)
In order to improve the design and to control satisfactorily the operation of the modern sewage disposal and industrial waste treatment plants, a great deal of work remains to be done by competent sanitary engineers, biologists, and chemists. It is the general belief that the stabilization of organic wastes is a biological phenomena. This indicates that a concentrated study of the organisms that are responsible for such stabilization should be undertaken and the part that each organism contributes should be evaluated The lack of specific knowledge has resulted in "rule of thumb" methods of design and control. A considerable amount of work on the biology of sewage disposal has been done by the New Jersey Experiment Station (4)(5)(8); by C.T. Butterfield and Elsie Wattie of the U.S. Public Health Services (10) (13) and by others, but a concentrated effort is still needed. James B. Lackey (1), has done an excellent job in summing up the work accomplished to date in the field of sanitary biology in his article “Sewage Treatment Biology”. In this article, Dr. Lackey lists four things that must be known before a clear picture can be presented on the subject of sewage and waste treatment. These points are as follows: (1) More precise information on the species of each group of organisms working in treatment plants. (2) The relative abundance of each so that no important (numerically or volumetrically) organism is neglected. (3) The range-not optimum- of environmental conditions under which the organism works. (4) The work accomplished by the organisms - whether a small segment of the stabilizing process, or a large one. Gerald A. Rohlick (2), in discussing Lackey’s article, places special emphasis on additional experimental work that should be done on the activities of protozoa and higher forms of life. The editors of Savage Works Journal (3) have summed up the problem in the following statement, “When we can answer completely the what, how, who, when and why of the organisms that populate our digestors, aerators and trickling filters, we shall simultaneously solve the problems of treatment plant design and operation that are of present concern”. In an effort to contribute something to the fund of knowledge of sanitary biology, the author undertook an investigation based on the for needs suggested by Lackey. The investigation is divided into three major parts: (l) A preliminary investigation; (2) the construction of a pure culture testing apparatus; and (3) the testing of a pure culture of organisms. The complete investigation is confined to studies of the organisms found in the aerobic phase of treatment, the precise source being the trickling filter at the Virginia Polytechnic Institute sewage disposal plant. This confinement of purpose was to allow the investigator to conduct a concentrated study of a single phase of treatment. The preliminary investigation consisted of taking frequent samples from the trickling filter and examining them under the microscope. The predominate organisms were noted and the development of pure cultures of each was attempted. The construction of a pure culture filter consisted of an attempt to duplicate in the laboratory as nearly as conditions would allow, the actual conditions that exist in the trickling filter at the plant, while at the same time observing pure culture requirements and techniques. The testing of the organisms consisted of measuring the amount of purification exerted by the organism on a synthetic sewage as it passed through the filter. The results of this investigation should answer two questions: First, can a pure culture apparatus be constructed and operated with such success that it can be used as a standard device for determining in the laboratory the degree of purification exhibited by organisms in pure culture, and Second, is it possible for a pure culture of organism to carry on the purification process. The answer to the second question will, of course, depend on a positive answer to the first question. / Master of Science
20

Performance Evaluation and Yield Determination of a Full-Scale Biological Aerated Filter

Phipps, Scott Douglas 29 March 2001 (has links)
Biological aerated filters (BAFs) are an emerging wastewater treatment technology designed for a wide range of municipal and industrial applications. BAFs utilize an inert media, either dense granular or floating, which supports biomass retention in the filter bed. BAFs offer an alternative to typical biological treatment processes; however, knowledge of the process is often limited, especially in the US market. Through various studies, process improvements were made for filter media selection, backwash protocols, and hydraulic load effects. During the summertime monitoring, seeded and unseeded nitrified effluent BOD5 samples were performed on a full-scale BAF. Discrepancies were found between seeded and unseeded samples, which warranted further investigation. Four biological treatment seeds and a commercial microbial seed were screened for appropriate seed volumes in comparison to the glucose:glutamic acid (GAA) assay, a standard for BOD5 analysis. After initial screening, a range of seed samples was applied to the BAF effluent for BOD5 and cBOD5 analysis, and to GGA and carbonaceous GGA (cGGA) analysis. A proposed seed screening protocol was developed using a ratio of measured BOD5 values in comparison to theoretical GGA standard BOD5 values. Biomass observed yield values were calculated for the full-scale BAF. Three individual mass balances were conducted to quantify the consumption of soluble COD in the filter and the mass of influent particulate matter filtered from the waste stream. Retained particulate matter is a substrate source for the biomass; however, the particles must be hydrolyzed into metabolizable monomers before being consumed by the biomass. A bench-scale BAF was designed and constructed to investigate the degree to which particle hydrolysis occurred in the full-scale system. Additionally, fluorescein diacetate was used during one of the experiments as a model particulate substrate to quantify the activity associated with hydrolytic enzymes in the bulk-liquid. Hydrolytic activity by cell-free extracellular enzymes in the bulk-liquid increased when particle substrate was present. Therefore, it appears that cell-free extracellular enzymes participate in the hydrolytic mechanism for particle degradation. Biomass observed yields were calculated for the full-scale BAF using full-scale mass balances and bench-scale particle hydrolysis experiments. / Master of Science

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