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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.
1

Low temperature carbonization of coal and a study of the resulting tars

Layng, Thomas Ernest. January 1900 (has links)
Thesis (Ph. D.)--University of Illinois, 1915. / Biographical sketch.
2

Influence of tar insoluble and solvent insoluble constituents on the physical properties of coal tars ...

Volkmann, Ernest Wilhelm, January 1935 (has links)
Thesis (PH. D.)--Columbia University, 1935. / Vita. eContent provider-neutral record in process. Description based on print version record. Bibliography: p. 81-82.
3

Examination of low-temperature coal tar

Soule, Roland Phineas, January 1900 (has links)
Thesis (Ph. D.)--Columbia University, 1922. / Cover title. Vita. "Reprinted from Chemical & metallurgical engineering, vol. 26, nos. 20, 21, and 22, May 17, 24 and 31, 1922."
4

Influence of tar insoluble and solvent insoluble constituents on the physical properties of coal tars ...

Volkmann, Ernest Wilhelm, January 1935 (has links)
Thesis (PH. D.)--Columbia University, 1935. / Vita. Bibliography: p. 81-82. Also issued in print.
5

Liquid diffusion in porous media, referring in particular to the Athabasca tar sands

Hopper, David Allan January 1945 (has links)
[No abstract submitted] / Science, Faculty of / Chemistry, Department of / Graduate
6

Rates of penetration of solvents into bituminous sand

Tiedje, John Louis January 1945 (has links)
[No abstract submitted] / Science, Faculty of / Chemistry, Department of / Graduate
7

The development of improved road tar binders from indigenous coal tars and aspects of their use

Jamieson, Ian Laurence January 1977 (has links)
Thesis (Ph.D. (Engineering))--University of the Witwatersrand, Engineering Faculty (Civil Engineering), 1977 / The thesis deals with the development of improved road tarbinders in South Africa and their application in surface treatments and in mixes used for pavement wearing courses and base courses in this country. This work is timely in view of the country's current economic problems. Locally produced tarbinders are considerably less expensive than bitumen binders in inland areas; tar being produced in the Witwatersrand complex whereas locally refined bitumen is produced from imported crude oil. The annual expenditure on bitumen by the South African road industry is currently of the order of R26 000 0 0 0. However, previously it had been found that tarbinders were less durable than bitumen. [Abbreviated Abstract. Open document to view full version] / WS2017
8

The characterisation and modification of binders used in the manufacture of carbon anodes

Twigg, Anthony Nicholas January 1989 (has links)
No description available.
9

Investigation of thermal biomass gasification for sustainable small scale rural electricity generation in Uganda

Olwa, Joseph January 2011 (has links)
With the increasing need for renewable energy technologies in the world, biomass fuel transformation technology is growing towards meeting that need, among others. Challenges remain certain and new innovations are being tested in bid to overcome them with the application of biomass as energy source. This report presents some studies carried out into understanding the potential and challenges associated with utilization of biomass fuel, especially for technologies that are appropriate for rural applications.  Utilization of biomass gasification technologies is in the focus of this study.   The great potential biomass fuel provide to Uganda for possible energy production in small scale application is presented. This study was carried out to understand the possibility of using biomass as fuel in electricity power generation in Uganda. It takes into consideration the use of biomass gasification technology in energy production. Challenges related to the application of biomass fuels are discussed, mostly with tar and alkali metal compounds in the gas stream.   Suggested methods to combat some of the challenges with biomass fuels are pointed out in this study. Application of externally fired gas turbine (EFGT) system is a particular approach discussed and its technical performance analyzed.  The analysis revealed that efficiency of the EFGT system is greatly dependent on the heat exchanger effectiveness and on turbine inlet temperature. Optimum performance can be realized with air compression ratio of 3.4. It is also noted that fouling and deposition in the heat exchanger can affect its performance.   A related study carried out was on the retention of alkali metals in an updraft gasifier. The gasifier was chosen for possible integration with the EFGT system. Finding was that about 99% of the alkali metals are retained in the gasifier. It is anticipated that this would reduce on the deposition in the heat exchanger, reducing on maintenance time. A need is identified to determine the level of deposition mentioned. A simple thermodynamic modeling of the alkali metals condensation reaction on a high temperature heat exchanger surface was conducted. The results showed that with appropriate quantity of S in the raw fuel, alkali metals bounding with Cl are greatly reduced. Cl is passed out as gaseous HCl, leaving deposition of none corrosive sulphates. Recommendation is made to study this phenomenon in an experimental setting.   Biomass gasification technology integration with an internal combustion (IC) engine is also studied. Here requirements for the producer gas quality have been discussed. Some tests carried out with wood pellets and wood cylinders compared the yield of tar from the two physically different fuels.  Wood pellets were found to yield more tar than wood cylinders.   Economic analysis of biomass gasifier integrated with an IC engine running a generator of 100 kWe was carried out. Comparison with a diesel electricity generator of similar capacity was made for a scenario in Uganda over a project life of 20 years. Different Plant Capacity Factors (PCF) and fuel costs including subsidies were considered. The analysis showed that over long period of time biomass power plant was more beneficial than the diesel power plant at PCF over 40%. This is more pronounced with unsubsidized diesel fuel. / QC 20111206
10

The extraction of tar acids from high temperature tar ...

Lloyd, Theodore Cynric, January 1930 (has links)
Thesis (PH. D.)--Columbia University, 1931. / Vita. eContent provider-neutral record in process. Description based on print version record. "Literature cited": p. [57].

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