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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.
41

Design of medical waste treatment systems employing bioremediation

Carpenter, William K. 11 May 2010 (has links)
The design and development of a system for disinfecting medical waste at the site of origin is presented. Investigation of the current commercial systems that accomplish this task shows that they all expose the waste to physical conditions that are harmful to all forms of life. Further, most are very expensive to install and to operate. A recently developed biochemical process promises to effectively inactivate harmful pathogenic organisms economically and without the danger of extreme heat or poisonous chemicals. The biochemical process is not yet fully developed. Nonetheless, the development of a marketable system to take advantage of this technology has been initiated. The motivation for developing this technology and the particular system that will employ it is presented. A general overview of the system and components is presented. Previous and suggested future testing strategies are explained. Component interactions and process control are described. / Master of Science
42

An evaluation of criteria proposed to reauthorize the cleanup of superfund sites : case studies from EPA's Region X

Williamson, Gina Denise 18 May 1995 (has links)
Graduation date: 1996
43

Estimation Of Hazardous Waste Generation In Selected Sectors Of Ostim Oiz, Ankara

Kayabinar, Arzu 01 December 2010 (has links) (PDF)
In this study, Hazardous Waste Production potential for the selected priority sectors in OSTIM Organized Industrial Zone (OIZ), Ankara is investigated. A general inventory study is conducted based on both absolute and minor entries in Waste List of Regulation on General Principles of Waste Management, Annex 4. Processes included in priority sectors are identified / moreover, each process is analyzed in terms of inputs entering and outputs leaving. Generated hazardous wastes from each sector are classified as process based, side processes based, and non-process based. After determination of codes and amounts of wastes, hazardous qwaste generation factors are generally calculated as &quot / kg of waste generated per ton of product or raw material processed&quot / . Calculated hazardous waste generation factors are compared with the estimated ones in literature if there is any and a specific range is determined for each waste factor. By use of sector specific hazardous waste generation factors and total capacity values sectoral hazardous waste generation amounts are calculated for OSTIM OIZ. The most crowded and potentially polluter sectors are determined from 14 main producer sectors of OSTIM OIZ. Accordingly, machining, casting of ferrous metals, treatment and coating of metals, maintenance and repair of motor vehicles and manufacture of rubber products are selected priority sectors studied in this thesis study. It is observed that among selected priority sectors highest generation occurs in machining sector, which involve high amounts of 12 01 coded HWs as metal grindings and waste oil mixtures. In addition, manufacturing of rubber products sector has no significant hazardous waste generation.
44

Achieving environmental justice for the community of Opportunity, Montana an assessment of Superfund concerns /

Hasenbank, Kathleen Anne. January 2007 (has links)
Thesis (M.S.)--University of Montana, 2007. / Title from title screen. Description based on contents viewed June 18, 2007. Includes bibliographical references (p. 59-61).
45

Characterization And Lime Stabilization Studies On Artificially Lead Contaminated Soils

Gaurave, Kumar 07 1900 (has links) (PDF)
Hazardous waste substances are solid, semi-solid or non-aqueous liquids that exhibit characteristics of corrosivity, reactivity, ignitability, toxicity and infectious property. Major available options for management of hazardous waste include direct disposal into landfill or chemical treatment/stabilization of wastes prior to landfill disposal. Hazardous wastes are accepted for direct disposal in engineered landfills if they conform to the chemical concentration limit criterion (determined by water leach test followed by estimation of the concentration of the contaminant) and compressive strength (the material should have compressive strength > 50 kPa) criterion. Lead is classified as extremely toxic metal. Elevated levels of lead in water (surface and ground water) primarily arise from industrial discharges, and aerial deposition. During its residence in surface water bodies, the lead may interact detrimentally with aquatic life or be abstracted into public water supplies. According to National drinking water standards, the permissible limit of lead in drinking water is 0.05 mg/l. Deposition of air-borne lead, disposal of sewage sludge on land and disposal of industrial effluents on lands are major sources of lead contamination of soils. When incorporated in soil, lead is of very low mobility. Lead retained in soils can be slowly leached to the groundwater thereby impacting human health if consumed for potable needs. Alternatively lead deposited in soils can be absorbed by vegetation (crops/trees) and can impact human health on their consumption. Given the negative impacts of lead contamination on human health, the strong affinity of soils to retain deposited lead and the possible release for human consumption, this thesis focuses on characterization and chemical stabilization of artificially lead contaminated soils in the context of their disposal in hazardous waste landfills. The main objectives of the thesis are: characterize artificially lead contaminated soils for water leachability of lead and undrained strength characteristics as per CPCB (Central Pollution Control Board) guidelines in the context of disposal criteria in hazardous waste landfills. Artificially lead contaminated soils in compacted and slurry states are used in the thesis. Red soil (from Bangalore District, Karnataka) and river sand are used in the preparation of compacted and slurry specimens. The red soil and red soil-sand specimens are artificially contaminated in the laboratory by employing aqueous lead salt solutions as remolding fluids. Lead concentrations of 160 to 10000 mg/l are used in this study. The results of characterization studies with artificially lead contaminated soils help identify contaminated soil materials that require chemical stabilization prior to disposal into engineered landfills. Based on the results of characterization studies with artificially lead contaminated soils, lime stabilization coupled with steam curing technique is resorted to immobilize lead in the red soil-sand slurry specimens and mobilize adequate undrained strength to meet the criteria for disposal of lead contaminated soils in hazardous landfills. After this first introductory chapter, a detailed review of literature is performed towards highlighting the need to undertake chemical stabilization of artificially lead contaminated soils in Chapter 2. Chapter 3 presents a detailed experimental program of the study. Chapter 4 presents the physico-chemical and mechanical characterization of the artificially lead contaminated soils. The ability of artificially contaminated soils to release (artificially added) lead during water leaching is explained using lead speciation results performed using the Visual MINTEQ program. Experimental results illustrated that contamination of compacted red soil and red soil + sand specimens with significant lead concentrations (21 to 1300 mg/kg) resulted in major fractions of the added lead being retained in the precipitated state. Results of water leach tests revealed that lead concentrations released in the water leachates are far less than (0.0011 to 0.48 mg/l) limits prescribed by CPCB (2 mg/l) for direct disposal of lead contaminated materials into hazardous waste landfills. Unconfined compressive strengths developed by the lead contaminated red soil and red soil-sand specimens were significantly higher (100-2700 kPa) than the strength requirement (> 50 kPa) for direct disposal of hazardous wastes in engineered landfills. Lead contamination did not affect the unconfined compression strengths of the specimens as matric suction prevalent in the unsaturated compacted soils had an overriding influence on the cementation bond strength created by the lead precipitates. Visual Minteq tool was helpful in predicting the amount of added lead that was converted to insoluble precipitate form. However the amounts of water leachable lead determined experimentally and predicted by Visual Minteq were very different-Visual Minteq predicted much higher amounts of water leachable lead than experimentally determined. Experimental results revealed that the levels of lead released by the red soil-sand slurries in water leach tests were in excess (13 to 36 mg/l) of the permissible lead concentration (2 mg/l) for direct disposal of hazardous waste in landfills. Owing to water contents generally being in excess of their liquid limit water contents (w/wL ratio > 1) the slurry specimens exhibited undrained strengths below 1 kPa. Lime stabilization and steam curing of the contaminated slurry specimens was therefore resorted to control the leachibility of lead and increase undrained strengths to acceptable limits. Chapter 5 deals with lime stabilization of artificially contaminated slurries that do not meet the leachate quality (lead concentration in water < 2 mg/l) or compressive strength (> 50 kPa). Procedures are evolved for lime stabilization of such artificially contaminated soils to meet both the water leachate quality and compressive strength criteria. Lime stabilization together with steam curing of the lead contaminated slurry specimens effectively immobilized the added lead (2500 mg/kg) and imparted adequate compressive strengths to the contaminated red soil-sand slurry specimens. The lime stabilized contaminated specimens released marginal lead concentrations (0.03 to 0.45 mg/l) in the water leach; these values are much lower than permissible limit (2 mg/l) for disposal in hazardous landfills or values exhibited by the unstabilized specimens (13 to 38 mg/l). Lime addition rendered the contaminated specimens strongly alkaline (pH values ranged between 10.68 and 11.66). Combination of the experimental and Visual Minteq results suggested that precipitation of lead as hydrocerrusite in the alkaline environments (pH 10.68 to 11.95) is not the sole factor for marginal release of lead in water leach tests of the 4, 7 and 10 % lime stabilized contaminated specimens. It is possible that fraction of lead ions are entrapped within the cemented soil matrix. Water leach tests performed at range of pH values (pH 2.5 to 9.6) with 7 % lime stabilized specimens suggested that immobilization of lead as hydrocerrusite or as entrapment in the cemented soil mass in the lime stabilized specimens is practically irreversible even on exposure to extreme pH conditions. The lime stabilized contaminated specimens developed unconfined compressive strengths ranging from 100 kPa (4 % lime stabilized 40 % red soil-60 % sand specimen) to 1000 kPa (10 % lime stabilized 100 % red soil specimen). The significant growth of compressive strength upon lime stabilization is attributed to growth of inter-particle cementation bonds by the CAH (calcium aluminate hydrate) and CSH (calcium silicate hydrate) compounds formed by lime-clay reactions, slight reduction in void ratios and growth of strong inter-particle cementation bonds the during steam curing at 800C. The results of this thesis bring out a procedure to immobilize high concentrations of lead and develop adequate compressive strength of lead contaminated slurry specimens by lime stabilization + steam curing technique. The red soil acted as pozzolana in reactions with lime, while, steam curing accelerated the lime-soil reactions. The procedure can be extended to non-organic slurry wastes that are devoid of pozzolanic material (example, lead contaminated smelting sands). In slurry wastes devoid of pozzolana, materials such as fly ash can be added and the reactions between lime and fly ash would immobilize lead + develop adequate compressive strength. Also, similar to the methodology being adaptable for any non-organic slurries, it can also be extended to other toxic metal bearing wastes, example, zinc, cadmium and nickel.
46

Situating Cost-Benefit Analysis for Environmental Justice

Wohlmuth, Erik Michael 12 1900 (has links)
Cost-benefit analysis plays a significant role in the process of siting hazardous waste facilities throughout the United States. Controversy regarding definitively disparate, albeit unintentional, racist practices in reaching these siting decisions abounds, yet cost-benefit analysis stands incapable of commenting on normative topics. This thesis traces the developments of both cost-benefit analysis and its normative cousin utilitarianism by focusing on the impacts they have had on the contemporary environmental justice discourse and highlighting valid claims, misunderstandings, and sedimented ideas surrounding the popularity of cost-benefit analysis. This analysis ultimately leads to an alternative means of realizing environmental justice that both acknowledges the need for greater democratic interactions and attempts to work with, rather than against, the prevailing paradigm of reaching siting decisions.
47

The Role of Community Participation Mechanisms in the Search for Social and Environmental Justice in Vieques, Puerto Rico

Richardson, Belinda Lian 05 1900 (has links)
This paper assesses the continued community participation mechanisms, especially the Restoration Advisory Board, and the role of these mechanisms in the environmental cleanup of post U.S. military training operations in the current colonial situation of the Puerto Rican island municipality of Vieques. Today the community has many informal and formal mechanisms of organization meant to address the social, economic, health and environmental problems resulting from the Navy's presence on the island. These mechanisms are the cornerstone of the community's search for social and environmental justice. This paper provides a brief history of the Navy's presence on Vieques, the evolution of community participation mechanisms and an analysis of how these mechanisms allow the community to interact with public, private and government institutions involved in the cleanup. The research is centered around interviews with community members to discern whether they feel these mechanisms are effective in properly addressing community concerns. The case study of Vieques could also have international implications for the future of foreign military bases and toxic waste disposal around the world. Analysis of the effectiveness of community participation mechanisms could help marginalized communities deal with developed countries on issues that may concern human health and environmental risks as a result of the developed countries' activities. The analysis of community participation mechanisms can be used as a guide for Vieques and other communities around the world trying to achieve social, economic and environmental justice.
48

Improving Environmental Health Literacy and Justice through Environmental Exposure Results Communication

Ramirez-Andreotta, Monica, Brody, Julia, Lothrop, Nathan, Loh, Miranda, Beamer, Paloma, Brown, Phil 08 July 2016 (has links)
Understanding the short-and long-term impacts of a biomonitoring and exposure project and reporting personal results back to study participants is critical for guiding future efforts, especially in the context of environmental justice. The purpose of this study was to evaluate learning outcomes from environmental communication efforts and whether environmental health literacy goals were met in an environmental justice community. We conducted 14 interviews with parents who had participated in the University of Arizona's Metals Exposure Study in Homes and analyzed their responses using NVivo, a qualitative data management and analysis program. Key findings were that participants used the data to cope with their challenging circumstances, the majority of participants described changing their families' household behaviors, and participants reported specific interventions to reduce family exposures. The strength of this study is that it provides insight into what people learn and gain from such results communication efforts, what participants want to know, and what type of additional information participants need to advance their environmental health literacy. This information can help improve future report back efforts and advance environmental health and justice.
49

Právní úprava nakládání s nebezpečným odpadem / Legal regulation of hazardous waste management

Špicarová, Michaela January 2012 (has links)
This study analyses legal regime of hazardous waste management. Study analyses international legal regime and describes the most important conventions and agreements and also introduces relevant international organizations. Next part of study is about European legal regime of hazardous waste, on which is based Czech regulation. Final parts deal with Czech regulation. There si briefly introduced Act no. 185/2001 and short history view. Last part deals with every method of hazardous waste management and also analyses waste hierarchy.
50

Studie obsahu nebezpečných odpadů v komunálním odpadu ČR / Study on the content of hazardous waste in municipal waste in CR

Machová, Daniela January 2013 (has links)
It is quite complicated to evaluate the hazardous waste production and management because the terminology is inconsistent and the legislation differs across countries. This makes it very difficult to compare data among countries and even within the same one. Hence the same data may vary by several tens of percent if they are generated according to different directives. This work deals with evaluation of the production of hazardous waste belonging to the group 20 in Catalogue of wastes. The total production of the hazardous waste from municipalities and citizens (households) is evaluated over a period 2008 - 2011 and the production in the capital city of Prague is for a term of 2006 - 2012. All the types of hazardous waste of the group 20 in Catalogue of wastes cannot be treated individually, due to their high number, and therefore they were arranged into seven groups, which were further processed statistically. The dominant component in both test cases is paint, the total production contains also big amount of electrical waste, fluorescent lamps and batteries. An important part of this work is to compare the composition of household waste originating from three different types of installations - housing estates, mixed and rural. Contrary to my original expectations, the most hazardous waste comes...

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