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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.
241

An assessment of alternative wastewater treatment approaches in Guangzhou

陶鷹翔, Tao, Yingxiang. January 1999 (has links)
published_or_final_version / Urban Planning and Environmental Management / Doctoral / Doctor of Philosophy
242

Sludge management in Hong Kong

Mak, Keung-kan., 麥強根. January 1994 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
243

Oceanic treatment: is this the only wayout?

Ip, Ho-yin, Nelson., 葉浩然. January 2001 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
244

A review of the use of salt water for flushing in Hong Kong: project report

Ip, Chi-kuen., 葉志權. January 1993 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
245

Dewatering and treatment of sewage sludge before landfill

Ng, Yue-hang., 伍宇鏗. January 1995 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
246

Study of marine disposal of night-soil in Hong Kong

Tin, Yuen-kwan., 田延昆. January 1974 (has links)
published_or_final_version / Civil Engineering / Master / Master of Philosophy
247

Algal sludge disposal in waste-water reclamation

Parker, Clinton Eldridge,1935- January 1966 (has links)
An alum coagulation treatment facility employing mixing, flocculating, and settling units, designed by criteria commonly used in the design of water treatment facilities, was operated to determine whether or not it could effectively remove algae and other suspended matter from raw sewage stabilization lagoon effluent. Algal sludge produced by the treatment facility was investigated: (1) to evaluate its potential as a soil conditioner; (2) to determine whether a stabilization lagoon could be used for algal sludge disposal; and (3) to determine whether or not sludge recirculation would reflect a chemical savings. The experimental lagoons and treatment facility, owned by Sanitary District No. 1 of Pima County, Arizona, were located near Tucson, Arizona. It was found, in a field study, that mixing, flocculating, and settling units commonly used for water treatment were efficient in clarifying lagoon effluent and produced a water with the appearance of tap water. Active photosynthesizing algae, producing high oxygen concentrations in lagoon effluent, caused flotation of alum coagulated algal sludge; however, by selecting lagoon effluent low in dissolved oxygen content, algal sludge flotation in the treatment facility was prevented. Algal sludge with Less than one percent total solids was readily dewatered in three days by sand bed drying. Resuspension of air dried algal sludge resulted in a maximum moisture uptake of 50 percent of the final wet weight. Dry algal sludge contained 47 to 61 percent volatile solids, 1.6 to 5.2 percent total phosphorus, and 3.6 to 4.9 percent organic nitrogen. No significant amount of ammonia nitrogen or nitrite-nitrate nitrogen was present in the sludge. The composition and characteristics of dry algal sludge indicate applicability as an aid to soil conditioning. For three months the characteristics of a lagoon used for algal sludge disposal were compared with a control lagoon operated in parallel; it was found that the returned algal sludge was not detrimental to the stabilization process. Acid treated and non-acid treated algal sludge produced from completely treated lagoon effluent had a clarifying value when reused with alum to coagulate effluent, but neither acid treated nor nonacid treated sludge produced from partly treated effluent caused additional clarification when returned with the same coagulant dose that initially produced the sludge. None of the different types of return sludge investigated had a clarifying value when returned under operating conditions necessary to obtain a coagulant savings.
248

Investigation to determine the effectiveness of a commercially available pit latrine additive and the development and evaluation of a testing protocol.

Bindoff, Anna Maria. January 2008 (has links)
The provision of sanitation services during the apartheid era in South Africa was minimal or non-existent in the previous "black" areas and for farm workers. Whatever service that was provided was often in a bad state of disrepair. One of the priorities established in the post 1994 elections was to improve the quality of lives for the previously marginalised and neglected communities. This was done through the development and implementation of a policy for reducing the sanitation backlog, and for the provision of a basic level of sanitation. The principles encompassed in the policies developed for poverty alleviation and sustainable development had many points in common with the United Nations Millennium Development Goals and targets declared in 2000. The provision of Ventilated Improved Pit (VIP) latrines by municipalities satisfies the minimum requirements for basic sanitation. This provision together with the awareness programs are seen to offer communities an improved environment and hence living conditions. Problems arise however, due to the rapid filling, blockages and even the overflow of these pits. The emptying of these pits is also hazardous due to the nature of the waste. One of the solutions proposed by entrepreneurs was to supply additives that would enhance the degradation processes in the pit thereby increasing the Iifespan of these pits as well as offering other benefits; reduced odours, and flies. The aim of this research work was to test the claim of enhanced degradation by determining the effectiveness of an additive, M, which was deemed to be representative of a group of additive; made up of aerobic microbes and enzymes. The objective was to supply information to the municipality planners and decision makers in municipalities to assist them in their planning for improved management of pits. Waste was removed from suitable VIPs and used as samples for laboratory scale experiments. Reactor vessels were designed to simulate pit conditions. The additive was tested on the waste as recommended by the supplier and compared in activity against waste tested as references. The reference tests had (i) no addition of additive or water, as well as (ii) varying the volume of water added and (iii) varying the frequency of water addition, no additive added. Measurements were made of the following variables: • Total mass • Chemical oxygen demand. • Total solids • Volatile solids. • Ash. The results of the experimental vessels were analysed and compared with the reference vessels to reveal any differences. The results obtained did not present enough precision and reliability to make any conclusive decision as to whether the additive is effective or not. Recommendations made were to improve the test methodology using the same additive, to obtain results that would make a conclusive decision possible. / Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2008.
249

An assessment of the management of odour at the Athlone wastewater treatment works, Cape Town

Takwi, Colette Nchong January 2017 (has links)
Thesis (MTech (Environmental Management))--Cape Peninsula University of Technology, 2017. / ¹Odour nuisance is increasingly becoming one of the major environmental problems in various countries across the world, especially odour associated with wastewater (Alfonsin et al., 2015; Schlegelmilch et al., 2005; Gostelow et al., 2001). As a result, the management of odour from Wastewater Treatment Works (WWTW) has become one of the environmental challenges besetting these facilities in recent times. The dispersion of odour across the physical boundary of wastewater treatment facilities presents not only negative environmental impacts to the natural environment, but also constitute a nuisance to surrounding populations. The Athlone (WWTW) located in the urban City of Cape Town with high demographics and adjacent to sensitive communities is thus not immune to poor air quality associated with WWTW activities (Walton, 2005). The population growth due to rural-urban migration has further put severe pressure on the facility and thus worsening the odour problem in the area. As a result, complaints have been received by the City Council from the surrounding communities over the last 20 years. In response to these complaints, the management of the WWTW introduced an odour management system with a particular focus on the use of a biotrickling filter coupled with the use of odour masking sprays. This management intervention was adopted in order to control the odour emitted to the atmosphere from the facility (WWTW). While these measures are said to reduce the prevalence of odour to the surrounding environment, it was, however, not clear whether or not such management interventions have reduced odour emitted from the treatment plant. This research was premised on two postulations as an approach to analyse the effect of the odour management plan adopted by the Athlone WWTW’s management and these are: 1) the perceived experience of odour by the adjacent neighbouring communities and, 2) the understanding of the inherent atmospheric dynamics (such as wind velocity, atmospheric stability, inversion layer and ventilation) which influence odour dispersal in the area. The research project argues that these two factors should be taken into account to ensure that the management of odour is sustainable. It is within this background that the research aimed at assessing the management of odour at the Athlone WWTW and to find out, if at all, the inherent local atmospheric conditions in the area and views of the surrounding communities are incorporated into the management of odour from the plant. The methodological design adopted in the study was case study approach. However, the atmospheric data (wind speed and direction) was obtained from the South African Weather Service (SAWS). These variables were analysed qualitatively and experimentally by the use of wind diagrams to provide insight on 2atmospheric stability conditions, surface inversion and topographical properties, and how these phenomenon influences odour dispersion. The study also reviewed previous odour management reports produced by the Althone WWTW management. This type of data was finally supported by data collected from the community by means of a community survey, face-to-face in-depth interviews and qualitative observation. Some major findings from the study revealed that the local weather of Athlone influences the dispersion of odour – facilitating dispersion in the summer through high wind velocities, while impeding dispersion during winter due to the presence of atmospheric stability conditions. Prevailing odours in this community has led to a general feeling of displeasure amongst community members especially since the management of the treatment plan does not include the local community in the decision-making process. In spite of these, the facility’s management approach was found to be more of a response driven nature even though it is ranked as a high-risk facility.
250

Occurrence, fate and effects of selected pharmaceuticals in sewage treatment plants.

January 2011 (has links)
Guan, Lijie. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 139-161). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Table of contents --- p.vii / List of Figures --- p.X / List of Tables --- p.xiii / Abbreviations --- p.xiv / Chapter 1. --- INTRODUCTION --- p.1 / Chapter 1.1 --- Source and Fate of Pharmaceuticals in the Environment --- p.1 / Chapter 1.2 --- Occurrence of Pharmaceuticals --- p.2 / Chapter 1.2.1 --- Wastewater --- p.2 / Chapter 1.2.2 --- Sewage sludge and soil --- p.5 / Chapter 1.2.3 --- "Surface water, ground water and seawater" --- p.6 / Chapter 1.2.4 --- Drinking water --- p.9 / Chapter 1.3 --- Effects on the Environment --- p.11 / Chapter 1.3.1 --- Antibiotic resistance --- p.11 / Chapter 1.3.2 --- Ecotoxicity on the aquatic organisms --- p.14 / Chapter 1.4 --- Removal in the Environment --- p.19 / Chapter 1.4.1 --- Adsorption --- p.20 / Chapter 1.4.2 --- Photodegradation and hydrolysis --- p.22 / Chapter 1.4.3 --- Biodegradation --- p.23 / Chapter 1.5 --- Analytical Method of Pharmaceuticals in Environmental Samples --- p.25 / Chapter 1.5.1 --- Solid-phase extraction --- p.25 / Chapter 1.5.2 --- Liquid chromatography mass spectrometry --- p.30 / Chapter 1.6 --- Objectives and Outline of Thesis --- p.33 / Chapter 2 --- OCCURRENCE AND FATE OF SELECTED PHARMCEUTICALS IN STPS --- p.35 / Chapter 2.1 --- Introduction --- p.35 / Chapter 2.2 --- Materials and Methods --- p.36 / Chapter 2.2.1 --- Choice of pharmaceuticals for study --- p.36 / Chapter 2.2.2 --- Description of sewage treatment plants (STPs) --- p.41 / Chapter 2.2.3 --- Experimental approach --- p.49 / Chapter 2.3 --- Results and Discussion --- p.55 / Chapter 2.3.1 --- Occurrence of azithromycin --- p.55 / Chapter 2.3.2 --- Fate of azithromycin --- p.59 / Chapter 2.3.3 --- Occurrence of erythromycin --- p.63 / Chapter 2.3.4 --- Fate of erythromycin --- p.67 / Chapter 2.3.5 --- Occurrence of roxithromycin --- p.70 / Chapter 2.3.6 --- Fate of roxithromycin --- p.74 / Chapter 2.3.7 --- Occurrence of atenolol --- p.75 / Chapter 2.3.8 --- Fate of atenolol --- p.79 / Chapter 2.3.9 --- Occurrence of simvastatin --- p.81 / Chapter 2.3.10 --- Fate of simvastatin --- p.84 / Chapter 2.3.11 --- Fate of pharmaceuticals during different treatment process --- p.85 / Chapter 2.3.12 --- Contribution of industrial (manufacturing) plants to STPs --- p.87 / Chapter 2.3.13 --- Seasonal variation --- p.87 / Chapter 2.4 --- Summary --- p.90 / Chapter 3 --- EFFECTS OF PHARMACEUTICALS ON ACTIVATED SLUDGE BACTERIA --- p.91 / Chapter 3.1 --- Introduction --- p.91 / Chapter 3.2 --- Materials and Methods --- p.92 / Chapter 3.2.1 --- Growth inhibition test --- p.92 / Chapter 3.2.2 --- Nitrification inhibition test --- p.94 / Chapter 3.3 --- Results and Discussion --- p.96 / Chapter 3.3.1 --- Growth inhibition of activated sludge bacteria --- p.96 / Chapter 3.3.2 --- Inhibition of nitrifying bacteria --- p.102 / Chapter 4 --- BIODEGRADATION PATHWAYS OF FOUR PHARMACEUTICALS --- p.106 / Chapter 4.1 --- Introduction --- p.106 / Chapter 4.2 --- Materials and Methods --- p.107 / Chapter 4.2.1 --- Test procedures --- p.107 / Chapter 4.2.2 --- Detection method --- p.108 / Chapter 4.3 --- Results and Discussion --- p.109 / Chapter 4.3.1 --- Degradation of atenolol --- p.109 / Chapter 4.3.2 --- Degradation of azithromycin --- p.117 / Chapter 4.3.3 --- Degradation of erythromycin --- p.129 / Chapter 4.3.4 --- Degradation of roxithromycin --- p.133 / Chapter 4.4 --- Summary --- p.134 / Chapter 5 --- GENERAL CONCLUSIONS --- p.136 / References --- p.139

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