الفهرس | Only 14 pages are availabe for public view |
Abstract Due to the scarcity of potable water in some places and high cost of energy used in saline water desalination, researchers turned to maximize the utilization of solar energy as a clean and renewable energy source used with water distillation where they worked to develop technology in this field to improve its efficiency and productivity. Desalination process based on the evaporation of saline water using the absorbed heat by the absorber. The evaporated steam is condensed on the glass covers and collected as distillated water. A lot of authors studied many methods to improve the performance of solar stills. One of these methods is using a solar collector coupled with the solar still. This present work presented an experimental and theoretical investigation for saline water desalination using double slope solar still coupled with an evacuated tube solar collector. The effect of operating parameters on the system performance was studied at different operation methods. These parameters include saline water temperature, absorber temperature, glass temperature, ambient temperature, hot water in and out temperatures. Total production and efficiency for all methods of operation are presented experimentally and theoretically. The maximum productivity obtained was achieved by day and night method of operation with 11.6 kg/m2.day experimentally and 12.48 kg/m2.day theoretically. The experimental and theoretical efficiency for all systems is presented. Organization of the thesis The thesis comprises five chapters as follows: Chapter 1 shows introduction about drinking water properties, desalination methods and solar stills. In addition, the chapter exhibits literature review for previous researches and ends with the objective of this thesis. Chapter 2 includes the characterization of the evacuated tube solar collector and the detailed description of the solar still. In addition, the specifications of the instruments and measuring techniques used in the experimental work are explained. Chapter 3 illustrates the mathematical model of the system used for the different methods of operation. All the equations needed to build up MATLAB program are presented. Chapter 4 exhibits the results obtained from experimental and theoretical work. They are presented in the following sequence: conventional solar still, night still, day and night still, 60°C to 60°C and 90°C to 90°C. The temperatures of all needed points; absorber, saline water, glass, ambient, salt water inlet, hot water inlet and outlet are presented experimentally and theoretically. Accumulative productivity for all operation methods is presented experimentally and theoretically. Finally, a comparison between the experimental and theoretical results is presented. Chapter 5 includes the conclusions obtained from the present experimental and theoretical work and suggestions for the future work. |