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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

A bench-scale examination of the effect of static mixers on the disinfection of cryptosporidium parvum

Heindel, Heather Lee 12 1900 (has links)
No description available.
42

Treatment of phenol with two-stage anaerobic filter processes

Cheng, Sheng-Shung 12 1900 (has links)
No description available.
43

Some chemical aspects of rapid sand filtration

Crapps, David Kenneth 08 1900 (has links)
No description available.
44

Chemical oxidation of aquatic antibiotic microcontaminants by free and combined chlorine

Dodd, Michael 05 1900 (has links)
No description available.
45

Filtration and backwashing performance of biologically-active filters

Ahmad, Rasheed 05 1900 (has links)
No description available.
46

Treatment of turbid surface water for small community supplies

Pardon Ojeda, Mauricio January 1989 (has links)
No description available.
47

Evaluation of physiochemical qualities and heavy metal levels of the final effluents of some wastewater treatment facilities in the Eastern Cape Province of South Africa

Kulati, Thanduxolo Cullinan January 2016 (has links)
Water is the most abundant substance in nature and vital for life activities. The major water sources for use are surface water bodies such as rivers and lakes, and underground aquifers and pore spaces down the water table (Ring, 2003). Water derived from these sources is not necessarily pure since it contains dissolved inorganic and organic substances, living organisms (viruses, bacteria, etc). For these reasons, water intended for domestic uses should be free from toxic substances and microorganisms that are of health significance (WHO, 2005). The availability and quality of water always have played an important role in determining the quality of life. Water quality is closely linked to water use and to the state of economic development (Chennakrishnan et al., 2008). Ground and surface waters can be contaminated by several sources. In urban areas, the careless disposal of industrial effluents and other wastes may contribute greatly to the poor quality of water (Mathuthu et al., 1997). In most developing countries, most areas are located on the watersheds which are the end points of effluents discharged from various industries (Oberholster and Ashton, 2008). South Africa, as a developing country, is experiencing rapid demographic changes due to urbanization, industrialization and population growth. The country has also been identified as being water-scarce, which can lead to a challenge of meeting the increasing water demand due to industrialization and urbanization. Such population growth increase may result in an increase in wastewater output, especially around urban areas.
48

Modelling and optimal control of countercurrent ion exchange process

Dube, Nthuthuko Marcus January 2002 (has links)
Thesis (MTech (Electrical Engineering))--Peninsula Technikon, Cape Town, 2002 / The problem for wastewater treatment is very important these days because of population increase and industry development. Ion exchange technology has proved its positive qualities in domestic lives and industry, but the ion exchange process still needs deeper understanding and improving. That is why a new pilot plant has been built in Chemical Engineering Department at Peninsula Technikon. In addition to the treatment of domestic effluents there are other processes which the ion exchange is suited for, such as the recovery and the reuse of industrial effluents. The proposed control system is developed in such a way that it does not have to depend on a certain effluent. The selection of the process and the development of techniques for its control fall into the national needs of improving people's lives (e.g. giving them excess to clean water) and quality of the environmental conditions (treatment of toxic waste substances). There is a need for an application area for modeling and control methods developed in the field of control engineering for the Department of Electrical Engineering; on the other hand a need of control techniques for the development in the Department of Chemical Engineering technological process. This multidisciplinary liaison between the two Engineering departments promotes joint research activities and relevance between them. It also equips the graduating engineer with the relevant experience into working in a team of multidisciplinary engineering fields.Community and industrial relevance of the research study is that in addition to treatment of domestic effluents, the ion exchange process is also particularly well suited for: the desalination of hard waters, combined neutralization and desalination of alcohol effluents, such as mine drainage, acid mineral tailings, paper bleach affluent. the pretreatment of reverse osmosis feed for the removal of organic and colloidal particulate.
49

Investigation of process parameters and development of a mathematical model for the purposes of control design and implementation for a wastewater treatment process

Du Plessis, Sydney Charles January 2009 (has links)
Thesis (DTech (Electrical Engineering))--Cape Peninsula University of Technology, 2009 / The problem for effective and optimal control of wastewater treabnent plants is very important recently because of the increased requirements to the qualitY of the effluent The activated sludge process is a type of wastewater process characterized with complex dynamics and because of this proper control design and implementation strategies are necessary and important for its operation. Since the early seventies, when a major leap forward was made by the widespread introduction of dissolved oxygen control, little progress has been made. The most critical phase in the solution of any control problem is the modelling stage. The primary building block of any modem control exercise is to construct and identify a model for the system to be controlled. The existing full Activated Sludge Model 1 (ASM1) and especially University of Cape Town (UCT) models of the biological processes in the activated sludge process, called in the thesis biological models, are highly complex because they are characterised with a lot of variables that are difficult to be measured on-line, complex dependencies and nonlinear interconnections between the biological variables, many kinetic parameters that are difficult to be determined, . different time scales for the process dynamics. The project considers reduction of the impact of the complexity of the process model over the methods for control design and proposes a solution to the above difficulties by development of a reduced model with small number of variables, but still with the same characteristics as the original full model for the purposes of real time.
50

The removal of impurities from a process stream

Himmelstutzer, EA January 2002 (has links)
Thesis (MTech (Chemical Engineering))--Cape Technikon, 2002. / The high purity 1-octene produced by Sasol Alpha Olefins in Secunda and which is sold to DOW Chemical Company for co-monomer application, has performed poorly over the DOW Ziegler-Natta catalysts. The reason for the poor performance was catalyst poisoning caused by low-level impurities present in the 1-octene. Much work from Sasol and DOW has gone into identifying the components responsible for catalyst deactivation, as well as methods suitable for removing them without significant 1-octene losses. Super NMP (n-Methyl-2-Pyrrolidone) extractive distillation piloting was performed previously on 1-octene in order to remove the low-level impurities that deactivate the DOW catalysts. VLE (vapour liquid equilibrium) test work performed previously indicated that all xylenol isomers are more promising as extractive distillation solvents than NMP.

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