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No description available.

While the quest of the human civilization continues towards a more sustainable energy resource, current energy conversion technologies need to be improved such that the rate of environmental impact that has occurred due to the rapid industrialization since the 20th century is mitigated. This search has motivated research into new energy conversion technologies that aim to reduce the environmental impact by either improving the efficiencies of existing technologies, developing new technologies with zero emissions or by improving reliability and reducing the cost of renewable energy. Process intensification through process integration is one of the areas of active research that improves the system efficiency by exploiting the synergies that exist between different processes. This thesis considers the design and operational feasibility of heat integrating two conventional industrial processes – gasification and steam reforming of methane for application in polygeneration. To this end, complex mathematical models that describe the integrated system are developed to study different design prospects and to determine if the device can be safely operated in a plant producing electricity, liquid fuels and hydrogen. The designs proposed in this thesis show that significant methane conversion comparable to industrial reformers can be achieved while providing the required cooling duty to the gasifier. The proposed integrated system produces hydrogen rich reformer synthesis gas (hydrogen and carbon monoxide) that can be blended with the hydrogen lean coal synthesis gas providing flexibility to change the molar H2/CO ratio necessary for different downstream processes in a polygeneration plant. Moreover, the results show that the integration helps improve plant carbon efficiency and reduce CO2 emissions. The major contribution of this thesis is the development of designs based on representative mathematical models that are safe to operate for producing several chemicals in polygeneration plants. / Dissertation / Doctor of Philosophy (PhD)

In the present era, with the prevailing competition, the cost of production plays a vital role. As the price of petroleum oils, especially diesel and furnace oil are growing at a steeper rate than solid fuel price, finding a substitute for furnace oil is one of the alternative available. Furnace oil used in boilers can be totally substitute by biomass with an equivalent ratio of 3.5:1 kg/liter on the basis of calorific value. This may results in saving of more than 60% of operating cost and would have attractive payback period of 6-8 months. Sri Lanka has large agriculture base and very common of having Gliricidia as an under-grow. The other biomass fuels such as paddy husk, saw dust, firewood are also available in large quantities around the country. Objective of this article is to study the conversion of presently  running furnace oil fired boiler, which is located at Ambilipitiya paper factory,Sri Lanka to biomass fired external furnace boiler namely water-wall boiler, techno economical study of the project and commissioning. Further a case study, which was done previous to this study and running successfully, is described to show the viability of the conversion using the internal furnace method. This case study was done at a Textile factory namely Brandix Finishing, Siduwa, and Sri Lanka. The results will be reducing the operating cost of the boilers and reduction of green house gas emission.  Opportunities for rural people to get extra income by farming Gliricidia, extra income from saw dust, paddy husk, and firewood are indirect benefits of the project. This report gives details of technical, environmental and commercial aspects of this unique opportunity.      Supervised by: Dr.Primal Fernando, Senior Lecturer, University of Peradeniya

No description available.

No description available.

No description available.

A cogeneration system using a noncondensing steam turbine to simultaneously provide electricity and process steam to a citrus plant was modeled in order to assess the source energy savings and the economic implications with the employment of this type system under conditions of time varying plant energy demand. Average monthly energy demand data from on citrus plant was analyzed. It was determined that the important parameter, in addition to a minimum demand level, for assessing economic acceptability is the demand thermal to electric ratio. One set of steam conditions will not necessarily provide the maximum source energy savings and at the same time be the most economically beneficial. The values of the economic criteria will remain relatively constant over a range of rated turbine capacities for each set of steam conditions.

<p> Water drops at their boiling point were projected through a steam atmosphere to strike a surface which was varied in temperature from 300 to 900 degrees Fahrenheit. A high-speed motion picture study of the collision process showed that, except at low surface temperatures, the drop flattened out on impact and rebounded in a state of oscillation. Measurements of the change in drop diameter on--collision indicated that the amount of evaporation due to heat transfer from the surface was extremely small except when the drop extensively wetted the surface. Solution of a mathematical model of the initial impact dynamics and models of heat transfer through a vapour film beneath the drop and by direct liquid-surface contact confirmed experimental observations. </p> / Thesis / Doctor of Philosophy (PhD)

The literature on stream reaeration was reviewed. A recirculating loop open channel system was desiqned and experiments were performed to study the effects of average stream velocity and temperature on the mass transfercoefficient for oxyqen dissolution into "clean" water. The applicability of the apparatus to the study of the effects of surfactants was also investigated. The velocity ranged from 0.1 to 0.9 ft/sec and the temperature from 5,0 to 25.o0c. The results indicated that the mass transfer coefficient varies approximately linearly with average stream velocity and that the temperature coefficient is a variable which depends on mixinq condHions. Furthermore, it was found that the temperature dependency of the mass transfer coefficient could be expressed as either a linear or power function. Correlations expressing the mass transfer coefficient in terms of easily measurable stream parameters. were developed and compared to those found in the recent literature / Thesis / Master of Engineering (ME)