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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.
291

Metropolitan Equipment: Architecture and Infrastructural Politics in Twentieth-Century New York City

Godel, Addison McMillan January 2021 (has links)
This dissertation explores architectural building types as critical components of, and unique points of interface with, three infrastructural systems, built or re-built in New York City in the decades after World War II. While contemporary infrastructure is enmeshed in regional and global networks far beyond the administrative bounds of the five boroughs, an architectural focus reveals these systems as inescapably local, tied to political struggles surrounding the siting, design, and construction of buildings; to socio-technical imperatives of density; to material consequences like traffic and air pollution; and to aesthetic effects like beauty, monotony, and monumentality. Three case studies—in food distribution, telephone service, and sewage treatment—explore different spatial techniques involved in the management of commodities, information, and waste. Reading each through the social history of technology, as well as the disciplinary tools of architectural history, brings to light unique aspects of architecture’s participation in the political, social, and technological landscapes of the contemporary city. This dissertation looks closely at the prewar roots and postwar creation of New York’s present-day systems: the adoption of the infrastructural buildings we see today, and the rejection of alternatives in design, values, and policies. It argues that the city’s vital systems, and their architectural manifestations, were largely designed according to the needs of various elite groups, in ways that supported the long-term deindustrialization and stratification of urban existence, though not according to a consistent or coherent plan. Well-studied postwar phenomena such as decentralization, automation, demographic change, and “urban crisis” take on different casts as familiar characters like politicians, property owners and architects are joined by monopoly corporations, technicians, and neighborhood organizers. Granular study of the processes that led to the adoption of particular plans, and the rejection of alternatives, reveals the city’s visual and functional landscape as one shaped by a wide—though far from democratic—range of actors. Today, these same infrastructures, physically durable even as their social use has been redirected or transformed, continue to participate in an ostensibly postindustrial and rapidly gentrifying city. By reexamining the narratives of these systems’ design and construction, the study of infrastructural architecture illuminates this inequitable history, while revealing moments of resistance and supporting calls for the further democratization of urban life by those whose needs have been discounted.
292

Perfluorinated compounds, bishenol a and acetaminophen in selected waste water treatment plants in and around Cape Town, South Africa

Adeleye, Adeola Patience January 2016 (has links)
Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2016. / The release of wastewater to the aquatic environment is most likely to introduce some trace levels of organic contaminants, some of which may be toxic, carcinogenic, or endocrine disruptors, as well as, persistent in the environment. Additionally, increasing contamination of surface waters by wastewater effluents has made water treatment processes more challenging and expensive. The presence of these pollutants in the receiving water body may have negative effects on aquatic species and often pose potential human health risks through the reuse of treated wastewater for drinking purposes and other household use. In countries like South Africa, Namibia, USA, Singapore and Australia, water agencies are intensifying wastewater reclamation/wastewater reuse as part of their water resource agenda: in order to meet the demands of the growing populations. Nowadays, water reuse is generally considered as a viable method of water supply management. This study focused on the identification of the occurrence, quantification of emerging contaminants and evaluation of removal efficiency in wastewater treatment processes of three classes of emerging contaminants (ECs) in wastewater: 1) six types of perfluorinated compounds (PFCs), namely; perfluorooctanoic acid (PFOA), Perfluorooctane sulphonate (PFOS), perfluoroheptanoic acid (PFHpA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUDA); 2) bisphenol A (BPA); and 3) Acetaminophen (ACP). These contaminants were identified and quantified in four wastewater treatment plants in the Western Cape. These treatment plants include three WWTPs in Cape Town, namely: Bellville WWTP, Scottsdene WWTP and Zandvliet WWTP and one WWTP in the central Karoo (Beaufort West wastewater reclamation plant).
293

Design of the step-feed activated sludge process

Moreno, Oswaldo January 1987 (has links)
No description available.
294

Analyses of the Water and Wastewater Systems at Florida Technological University

Jensen, Fred C. 01 January 1972 (has links) (PDF)
In searching for a subject to meet the M. S. Degree Research Report requirements, I had several objectives in mind. I wanted (1) a project with relevancy in the environmental field which would broaden my understanding of the environmental systems which I have studied, (2) a subject which would allow me to apply some of the Principles which I have learned in Operations Research , and (3) a project which had good practical application. With these objectives in mind, I reviewed the suggested topics presented by the Faculty and selected the FTU Water and Wastewater System Analyses topic which was recommended by Dr. Y. A. Yousef. After selecting the topic I became very interested in the application of Management Information Systems (MIS) and discussed with Mr. C. S. Bauer, the possibility of utilizing such a program to evaluate the data which I had accumulated. He concurred that this would be a good application of a MIS and encouraged my use of it. He provided me with a basic MIS program which he and his IEMS 496-13 class of 1971 had developed . To meet the requirements of this study it was necessary to add some programs and make modifications to the basic programs which provided me with an extensive involvement in computer programming and MIS operations. The application and use of the MIS has become an important part of this research paper. I have learned much in analyzing the FTU Water and Wastewater Systems and in applying the FTU Water and Wastewater Systems and in applying the Management Information System. It appears that a continuation of these studies with an increase of scope to encompass electrical and other mechanical utilities would be desirable. It would also appear that this study could have practical value in the management of the present utility systems and that FTU might elect to continue this or a similar MIS program as a part of the utilities operations. This type study should also have potential application for analyzing municipal and government operated facilities.
295

Denitrification in low pressure distribution onsite wastewater disposal systems

Degen, Marcia J. 14 October 2005 (has links)
The effects of effluent type, effluent loading rate, dosing interval, and temperature on denitrification in low pressure distribution, on-site wastewater treatment and disposal systems (OSWTDS) were evaluated in this study. The treatments were surface and subsurface soil horizons; nitrified and non-nitrified wastewaters; 0.5, 1.0, and 1.5 times the Virginia Department of Health (VDH 1989) recommended wastewater loading rate; 24 and 48 hour dosing intervals; and summer and winter temperatures. Surface and subsurface soil cores were collected from a Groseclose silt loam soil (clayey, mixed, mesic Typic Hapludult) and subjected to the various treatments. The effects of the treatments on denitrification were evaluated based on analyses of leachate from the cores, soil chemical analyses, and microcosm studies to estimate actual denitrification activity. A model was developed from the study that estimated the mean N₂O production for each combination of experimental treatments. The results of the study and the model indicate that denitrification can be enhanced in OSWTDS by the application of non-nitrified wastewater at one-half the VDH recommended loading rate, or 1.25 cm/day, for surface soil horizons (30 min inch⁻¹ percolation rate) using a 48 hour dosing interval. A field study was conducted on a Lowell silt loam soil (fine, mixed, mesic Typic Hapludalf). Denitrification was measured at this site using acetylene blocking and the results compared to those predicted by the denitrification model developed from the laboratory data. The field measurements of denitrification based on N₂O concentration in the soil atmosphere were three orders of magnitude higher than that predicted by the model. It was concluded that the laboratory techniques can be used to determine optimum method of operation for denitrification in a low pressure distribution system, but it cannot be used to determine the field design loading rates. / Ph. D.
296

Sewer System Design for Camp Challenge and Determination of Per Capita Wastewater Flows from Vacation Facilities

Goucher, William C. 01 January 1976 (has links) (PDF)
A sewer system was designed for Camp Challenge of the Florida Easter Seal Society, in Mount Plymouth, Florida, of polyvinyl chloride piping. Invert elevations were tabulized and necessary fittings determined for the system. Cost estimates were also included. The sewers were designed on a per fixture basis so as not to overdesign using per capita flow rates. A literature and records search was conducted to obtain design and actual wastewater flow quantities in gallons per capita per day (gpcd). Actual flows determined from 4 camps and 11 travel trailer parks gave average values of 39 and 33 gpcd, respectively, and can be used as design parameters for wastewater treatment facilities. However, further investigations and intensive flow monitoring are deemed necessary to provide a wider, more accurate data base with less variability.
297

Wastewater Treatment Plant Control

Knowles, David Milton 01 January 1972 (has links) (PDF)
This report is the result of investigation of the feasibility of increasing the use of autamatic controls at the Florida Technological University Wastewater Treatment Plant. This investigation was to include a literature search and visits to wastewater treatment plants. During the writers course of study, he was privileged to make a series of tests of a residual chlorine analyzer which was made in the school shop. Since this work was closely related to automatic controls the data are included in this report.
298

Effects of sewage treatment plant effluents on mollusks and fish of the Clinch River in Tazewell County, Virginia

Goudreau, Stephanie E. 22 June 2010 (has links)
The Clinch River is renown for its rich mollusk and fish assemblages, including many endemic species. New sewage treatment plants (STP's) have recently been constructed along the Clinch River in Virginia, raising concern because of the disappearance of mollusks below existing STP's. Field and laboratory studies were conducted to determine mollusk and fish distribution in proximity to two STP's in Tazewell County, and the tolerance of two mollusk species to mono chloramine and unionized ammonia, the major toxicants in domestic STP effiuent. River reaches up to 3.75 km downstream of the STP outfalls at Tazewell and Richlands were depauperate of mussels. Tolerance to effluent seemed to vary among snails, sphaeriid clams, and the Asiatic clam <i>Corbicula flumineaK</i>. After an initial toxic zone below the Tazewell outfall, abundance of fish appeared to increase by 0.45 km below the outfall. The effluent at Richlands eliminated intolerant species, and more tolerant species were present as far as 0.45 km below the outfall. Laboratory bioassays with glochidia of <i>Villosa nebulosa</i> resulted in 24-h EC₅₀ and LC₅₀ values of 0.042 and 0.084 mg/L monochloramine, respectively, and 24-h EC₅₀ and LC₅₀values of 0.237 and 0.284 mg/L unionized ammonia, respectively. Glochidia rank among the most sensitive invertebrates in their tolerance to these toxicants. The snail <i>Pleurocera unciale unciale</i> was moderately sensitive, with 96-h LC₅₀ values of 0.252 mg/L mono chloramine and 0.742 mg/L unionized ammonia. Comparison of monochloramine and unionized ammonia concentrations monitored at 0.10 km below the outfalls indicated that mono chloramine was the major toxicant likely affecting fauna. / Master of Science
299

Comparison of lime and sodium hydroxide for the control of gas production from sewage sludges

Thota, Ravi Meher 31 October 2009 (has links)
The effects of lime and sodium hydroxide on gas production from stored sewage sludge were examined. The impact of calcium on gas production was also investigated. The rate and volume of gas production and change in pH over time were monitored in all the reactors in an effort to study the relationship between chemical dose, pH, and gas production. The duration of inhibition of gas production increased with the lime dose. Gas production was initiated only after the pH in the reactors decreased to near 8.0. A decrease in pH was observed in all the lime dosed reactors with an initial pH less than 12.0. An initial pH greater than 12.0 was required to completely arrest organic acid and gas production. For the sludge used in this study, a quick lime dose of 0.36 Ib/lb of dry solids, which elevated the pH to higher than 12.0, was required for complete inhibition of gas production. Gas production and pH patterns observed in sodium hydroxide dosed reactors were similar to those in lime dosed reactors. A decrease in pH by nearly 2 pH units was observed in these reactors after calcium chloride addition. This was thought to be primarily due to the precipitation of calcium carbonate. Gas production after elutriation was observed in all the reactors with an initial pH less than 11.5. The volume of gas produced after elutriation decreased with increase in initial pH. An NaOH (19N) dose of 0.29 Ib/Ib of dry solids was required for permanent prevention of gas production. Calcium alone was not capable of arresting gas production but it reduced the total gas production in the reactors with a pH less than 7.5. At pH values greater than 7.5, calcium had little effect on gas production. / Master of Science
300

Availability and distribution of heavy metals from sewage sludge in the plant-soil continuum

Rappaport, Bruce D. January 1986 (has links)
An investigation was conducted using in situ lysimeters (1.5 m x 2.3 m) to determine Cd, Cu, Ni, and Zn availabilities for barley (Hordeum vulgare L.) and corn (Zea mays L.) grown on four sludge-amended soils. These lysimeters were constructed in Acredale silt loam (Typic Ochraqualf), Bojac loamy sand (Typic Hapludult), Davidson clay loam (Rhodie Paleudult), and Groseclose silt loam (Typic Hapludult) soils. An aerobically digested sewage sludge from a sewage system with major industrial inputs was applied at rates of 0, 42, and 84 dry Mg ha-t to the lysimeters in the poorly-drained Acredale soil. Rates of 0, 42, 84, 126, 168, and 210 dry Mg ha-1 were applied to the lysimeters in the well-drained Bojac, Davidson, and Groseclose soils. Tissue metal concentrations were determined in 1984 and 1985 for a three crop rotation, which consisted of corn, barley, and corn on the Acredale soil. Increases in sludge-borne Ni and Zn led to increases in Ni and Zn concentrations in corn earleaf, corn grain, and barley silage. Copper concentration was increased in barley silage but not in corn grain and stover. On this poorly-drained soil, metal movement did not occur below the Ap horizon even when Cu was applied in excess of USEPA guidelines. Although there were increases in metal levels, all four metals were within the range considered normal for corn and barley growth. Soil, corn, and barley plants were sampled in 1984 and 1985 to determine Cd, Cr, Cu, Ni, and Zn availabilities for crops grown on the sludge-amended Bojac, Davidson, and Groseclose soils. Levels of DTPA-extractable Cd, Cu, Ni, and Zn in the Ap horizon of these soils increased linearly with sludge rate. Corn grain and stover yields were not decreased on the Bojac, Davidson, and Groseclose soils when 4.5, 5105, 760, 43.0, 135, and 620 kg ha-1 of Cd, Cr, Cu, Ni, Pb, and Zn were added as a sludge-amendment. Copper and Zn applied in excess of 480 and 60 kg ha- 1 of USEPA guidelines, respectively on the Bojac, Davidson, and Groseclose soils were not phytotoxic to corn plants in 1984. Corn and barley tissue sampled for three consecutive seasons had Cr concentrations <2.8 mg kg-1. / Ph. D.

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